Anti-inflammatory salicylate treatment alters the metabolic adaptations to lactation in dairy cattle

Prepartum anti-inflammatory therapies in Holstein dairy cows blocked by parity and body condition score group: Effects on metabolic stress, systemic inflammation, performance, and health

The objective of this study was to assess the effects of prepartum administration of anti-inflammatory therapies on body condition score (BCS), β-hydroxybutyrate (BHB) concentration, haptoglobin (HP) concentration, milk yield, milk components, rumination time, clinical health events and reproductive performance in Holstein dairy cows. At 14 d before the expected calving date, cows (PAR; n = 170) and heifers (nulliparous [NUL]; n = 63) were blocked by BCS group (optimal = 3-3.5 [OPT]; over-conditioned cows [OVERC; BCS ≥ 3.75 pts.]) and parity (NUL; PAR) and randomly allocated to one of 3 treatment groups: 1) ASA (n = 78): receive one oral administration of acetylsalicylic acid (4 boluses; 480 grain/bolus); 2) MEL (n = 76): receive one oral administration with meloxicam (1mg/kg of BW), or 3) PLC (n = 77): receive one oral treatment with gelatin capsules filled with water. Body condition score was assessed, and blood samples were collected, weekly starting one week before treatment until 3 weeks after calving. Daily milk yields and daily rumination times were collected from on-farm computer records. Dairy Herd Improvement Association (DHIA) monthly test data were collected to assess milk yield, somatic cell counts, and milk components. Furthermore, health events, culling rate, and reproductive performance data were collected from on-farm computer records. The data were analyzed using MIXED, GLIMMIX, and LIFETEST procedures of SAS as a randomized complete block design. On average, MEL-NUL cows produced 4.77 ± 0.93 kg/d and 4.81 ± 0.92 kg/d more milk from wk 6 to wk 21 of lactation compared with ASA-NUL and PLC-NUL cows, respectively. Similarly, there was a week by treatment by body condition group interaction (P = 0.01), where OVERC cows treated with MEL produced more milk from wk 10 to wk 15 of lactation compared with ASA- OVERC and PLC-OVERC cows. Parous cows treated with ASA had lower BCS compared with PAR cows treated with MEL or PLC. A lower percentage of OVERC cows treated with ASA became sick in the first 60 DIM compared with MEL- OVERC and PLC- OVERC cows (ASA = 23.88 ± 7.26%, MEL = 46.36 ± 8.57%; PLC = 46.74 ± 8.53%; P = 0.04). Parous cows treated with ASA had (P = 0.03) a higher hazard ratio to become pregnant by 300 DIM compared with PAR MEL cows. Although the study was not sized for finding treatment differences in blocking criteria groups, these results suggest that treatment with prepartum anti-inflammatory therapies may have positive effects on milk yield and postpartum health in specific groups of cows, such as NUL and OVERC cows, while it may not be recommended for other animal categories, such as parous cows and cows with optimal BCS. Larger studies are needed to strengthen the associations observed in this study.

Effects of dietary butyrate supplementation and oral nonsteroidal antiinflammatory drug administration on uterine inflammation and interval to first ovulation in postpartum dairy cows

This study evaluated the effects of dietary butyrate supplementation and oral nonsteroidal antiinflammatory drug (NSAID) administration on uterine inflammation and the interval from calving to first ovulation (ICFO; in days). We hypothesized that a combination of dietary butyrate and oral NSAID would reduce uterine inflammation and decrease ICFO. Sixty-five cows were enrolled in a 2 × 2 factorial design and assigned to receive an iso-energetic diet containing a supplement of either butyrate (fatty acid-coated calcium butyrate) or control (commercial fat and calcium carbonate mixture) at 1.42% of diet dry matter, during the calving transition period from -28 (±3) to +24 (±3) days in milk (DIM; calving = d 0). At 12 to 24 h postcalving, cows received an oral NSAID (1 mg of meloxicam/kg of BW) or a placebo (food dye). Ovarian ultrasonography was performed weekly from 14 DIM until first ovulation or up to 56 DIM. Endometrial cytology was performed at 28 DIM to assess uterine inflammation based on polymorphonuclear leukocytes (PMN). No interactions were detected between treatments. The proportions of cows with high (>18%) endometrial PMN did not differ between butyrate and control diets or between NSAID and placebo. Mean (± standard error of mean) ICFO did not differ between butyrate (28 ± 2 d) and control (25 ± 2 d) or between NSAID (29 ± 2 d) and placebo (24 ± 2 d). However, the ovulation rate up to 56 DIM (hazard ratio: 0.61; 95% confidence interval: 0.35 to 1.04) established by survival analysis tended to be lower in NSAID than in placebo. In conclusion, dietary butyrate supplementation and oral NSAID administration did not reduce endometrial inflammation or the mean ICFO, but NSAID-treated cows tended to have a lower rate of ovulation up to 56 DIM.

Nutrigenomic Interventions to Address Metabolic Stress and Related Disorders in Transition Cows

For dairy cattle, the period involving a shift from late pregnancy to early lactation termed transition or periparturient is an excruciating phase. Health-related disorders are likely to happen in this time frame. Timely postpartum and metabolic adjustments to this new physical state demands correct management strategies to fulfill the cow's needs for a successful transition to this phase. Among the management strategies, one of the most researched methods for managing transition-related stress is nutritional supplementation. Dietary components directly or indirectly affect the expression of various genes that are believed to be involved in various stress-related responses during this phase. Nutrigenomics, an interdisciplinary approach that combines nutritional science with omics technologies, opens new avenues for studying the genome's complicated interactions with food. This revolutionary technique emphasizes the importance of food-gene interactions on various physiological and metabolic mechanisms. In animal sciences, nutrigenomics aims to promote the welfare of livestock animals and enhance their commercially important qualities through nutritional interventions. To this end, an increasing volume of research shows that nutritional supplementation can be effectively used to manage the metabolic stress dairy cows undergo during the transition period. These nutritional supplements, including polyunsaturated fatty acids, vitamins, dietary amino acids, and phytochemicals, have been shown to modulate energy homeostasis through different pathways, leading to addressing metabolic issues in transition cows.

Effects of dietary butyrate supplementation and oral nonsteroidal anti-inflammatory drug administration on serum inflammatory markers and productivity of dairy cows during the calving transition

Dairy cattle experience inflammation during the calving transition period, and butyrate and nonsteroidal anti-inflammatory drugs (NSAID) are expected to reduce the inflammation. Our objective was to evaluate the effects of dietary butyrate supplementation and oral NSAID administration on feed intake, serum inflammatory markers, plasma metabolites, and milk production of dairy cows during the calving transition period. Eighty-three Holstein cows were used in the experiment with a 2 × 2 factorial arrangement of treatments. The cows were blocked by parity and calving date, and randomly assigned to a dietary butyrate or control supplement, and NSAID or a placebo oral administration. Experimental diets were iso-energetic containing calcium butyrate at 1.42% of diet dry matter (DM) or the control supplement (1.04% commercial fat supplement and 0.38% calcium carbonate of diet DM). The close-up diets contained 13.3% starch and 42.4% neutral detergent fiber on a DM basis, and were fed from 28 d before expected calving date until calving. The postpartum diets contained 22.1% starch and 34.1% neutral detergent fiber on a DM basis and were fed from calving to 24 d after calving. Oral NSAID (1 mg of meloxicam/kg of body weight) or placebo (food dye) was administered 12 to 24 h after calving. Dietary butyrate supplementation and oral NSAID administration did not affect milk yield or postpartum serum concentrations of amyloid A and haptoglobin. However, butyrate-fed cows increased plasma fatty acid concentration on d -4 relative to calving (501 vs. 340 μEq/L) and tended to increase serum haptoglobin concentration (0.23 vs. 0.10 mg/mL). There was a supplement by drug interaction effect on plasma glucose concentration on d 4; in cows administered the placebo drug, butyrate supplementation decreased plasma glucose concentration compared with control-fed cows (62.8 vs. 70.1 mg/dL). Butyrate-fed cows tended to have lower milk crude protein yield compared with cows fed the control diet (1.21 vs. 1.27 kg/d). Dietary butyrate supplementation and oral NSAID administration did not have overall positive effects on production performance of dairy cows during the calving transition period.

The Impact of Dietary Berberine Supplementation during the Transition Period on Blood Parameters, Antioxidant Indicators and Fatty Acids Profile in Colostrum and Milk of Dairy Goats

The objective of this study was to investigate the effect of berberine (BBR) supplementation on productivity, antioxidant markers, and the fatty acid (FA) profile in the colostrum and milk of goats. Twenty-four primiparous Saanen goats were supplemented with 0, 1, 2, and 4 g/d (per goat) of BBR in control (CON), BBR1, BBR2, and BBR4 groups (n = 6 per group), respectively, from 21 days before expected kidding to 21 days after parturition. Blood sampling was carried out at -21, -14, -7, 0, 7, 14, and 21 d relative to delivery. Colostrum was collected within the first and second milking (d 1 of lactation), and milk was harvested weekly after kidding. Both BBR2 and BBR4 increased dry matter intake (DMI) (p ≤ 0.05) and energy balance (EB) as well as colostrum and milk production. Both BBR2 and BBR4 decreased (p ≤ 0.05) plasma levels of cholesterol, haptoglobin, and ceruloplasmin, while elevating the plasma albumin and paraoxonase (p ≤ 0.05), which may indicate that BBR mitigates inflammation during the transition period. BBR reduced (p ≤ 0.05) malondialdehyde (MDA) and increased (p ≤ 0.05) total antioxidant capacity (TAC), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and catalase (CAT) in blood, colostrum, and milk. Concentrations of de novo fatty acid in colostrum and milk were increased (p ≤ 0.05) with both BBR2 and BBR4. Free fatty acid (FFA) concentration in colostrum and milk fat were lower (p ≤ 0.05) in BBR2 and BBR4 compared to CON. The concentration of saturated fatty acids (SFAs) in colostrum and milk fat increased (p ≤ 0.05) with BBR2 and BBR4, while unsaturated fatty acids (USFAs) decreased (p ≤ 0.05) in milk. In summary, supplementation with at least 2 g/d BBR may enhance the EB and antioxidant status of dairy goats.

Effects of a single transdermal administration of flunixin meglumine in early postpartum Holstein Friesian dairy cows: Part 1. Inflammatory and metabolic markers, uterine health, and indicators of pain

The objectives of this study were to assess the effects of a single transdermal administration of flunixin meglumine (FM) in early postpartum Holstein Friesian dairy cows on serum concentrations of inflammatory and metabolic markers, uterine health, and indicators of pain. The hypothesis was that the anti-inflammatory, antipyretic, and analgetic effects of the pharmaceutic agent would reduce systemic inflammation, resulting in improved metabolic and inflammatory profile, diminished incidence of metritis, and reduced expression of pain. A total of 500 cows (153 primiparous, 347 multiparous) from 3 different commercial dairy farms in the northeast of Germany were included in a randomized controlled clinical trial. Farms were preselected based on high haptoglobin concentrations in their fresh lactating cows. Cows were excluded if they had experienced dystocia, stillbirth, or twin birth, or if they showed any signs of milk fever, retained fetal membranes, or fever (>40°C). The cows were treated once with either FM (3.33 mg/kg) or a placebo as control (CON) through transdermal administration between 24 to 36 h postpartum (d 2). General health examinations were performed (daily from d 2-8 and additionally on d 15 postpartum), vaginal discharge was assessed using the Metricheck device (d 8 and 15 postpartum) and serum samples were analyzed for inflammatory and metabolic markers (d 2, 4, and 6 postpartum). Effects of treatment, parity, sampling day, and their interactions were evaluated using mixed effects models. Primiparous cows treated with FM showed lower serum haptoglobin concentrations (0.90 ± 0.08 vs. 1.17 ± 0.07 g/L; ± standard error of the mean) and higher serum albumin concentrations (35.5 ± 0.31 vs. 34.8 ± 0.31 g/L) on d 6 postpartum. They also had a lower risk for purulent vaginal discharge with or without a fever compared with CON cows on d 15 postpartum (odds ratio for CON vs. FM: 1.63, 95% CI: 1.26-2.00), and body temperature was lower throughout the first 15 d in milk (39.1 ± 0.11 vs. 39.2 ± 0.11°C). Multiparous cows treated with FM had lower serum β-hydroxybutyrate concentrations on d 4 postpartum (0.71 ± 0.05 vs. 0.78 ± 0.05 mmol/L) and d 6 postpartum (0.74 ± 0.05 vs. 0.80 ± 0.05 mmol/L). Regardless of parity, FM-treated cows were significantly less likely to abduct their tail from their body (14.3 vs. 23.6%) and show an arched back (27.9 vs. 39.7%) on the day after treatment compared with CON cows. It can be concluded that FM treatment slightly reduced inflammation and diminished the risk for metritis in primiparous cows, improved metabolic profile in multiparous cows, and reduced expressions of pain in all cows.

Symposium review: The role of adipose tissue in transition dairy cows: Current knowledge and future opportunities

Adipose tissue (AT) is a central reservoir of energy stored in the form of lipids. In addition, AT has been recognized as an immunologically and endocrinologically active tissue of dairy cattle. The recent literature on AT biology of transition dairy cows has often focused on the possible negative effects that originate from excessive body fat. However, the highly efficient energy-storage capability of this tissue is also vital to the adaptability of dairy cattle to the change in nutrient availability, and to support lactation and reproduction. An excessive degree of mobilization of this tissue, however, is associated with high circulating fatty acid concentrations, and this may have direct and indirect negative effects on reproductive health, productivity, and disease risk. Furthermore, rapid lipolysis may be associated with postpartum inflammation. Research on the role of AT is complicated by the greater difficulty of accessing and measuring visceral AT compared with subcutaneous AT. The objective of this review is to provide a transition cow-centric summary of AT biology with a focus on reviewing methods of measuring AT mass as well as to describe the importance for production, health, and reproductive success.

The Antioxidant Properties of Selenium and Vitamin E; Their Role in Periparturient Dairy Cattle Health Regulation

Dairy cattle experience health risks during the periparturient period. The continuous overproduction of reactive oxygen species (ROS) during the transition from late gestation to peak lactation leads to the development of oxidative stress. Oxidative stress is usually considered the main contributor to several diseases such as retained placenta, fatty liver, ketosis, mastitis and metritis in periparturient dairy cattle. The oxidative stress is generally balanced by the naturally available antioxidant system in the body of dairy cattle. However, in some special conditions, such as the peripariparturient period, the natural antioxidant system of a body is not able to balance the ROS production. To cope with this situation, the antioxidants are supplied to the dairy cattle from external sources. Natural antioxidants such as selenium and vitamin E have been found to restore normal health by minimizing the harmful effects of excessive ROS production. The deficiencies of Se and vitamin E have been reported to be associated with various diseases in periparturient dairy cattle. Thus in the current review, we highlight the new insights into the Se and vitamin E supplementation as antioxidant agents in the health regulation of periparturient dairy cattle.

Associations between ultrasound measurements and hematochemical parameters for the assessment of liver metabolic status in Holstein-Friesian cows

Metabolic disorders, including hepatic lipidosis and ketosis, severely affect animal health status and welfare with a large economic burden in dairy herds. The gold standard for diagnosing hepatic lipidosis is the liver biopsy, which is impractical and invasive for the screening at farm level. Ultrasound (US) imaging is a promising technique for identifying liver dysfunction, but standardized specifications in physiological conditions are needed. Herein, we described the features of four US measurements, namely the liver predicted triacylglycerol (pTAG) content, liver depth (LD), and portal vein area (PVA) and depth (PVD) and we investigated their associations with a set of hematochemical (HC) indicators in 342 clinically healthy Holstein Friesian dairy cows. Liver pTAG content was negatively associated with hematocrit and positively with globulin, whereas PVA was negatively associated with thiol group levels, and LD positively with ceruloplasmin. We found significant interactions between some HC parameters and parity: in particular, creatinine, thiol groups and globulin for PVA, and aspartate aminotransferase, paraoxonase and ceruloplasmin for PVD. This study offers new insights on variations in liver function occurring after calving and pave the way for the potential use of minimally invasive techniques for prompt detection of metabolic disorders in dairy herds.

Effects of sodium salicylate and time postpartum on mammary tissue proliferation, gene transcript profile, and DNA methylation

Previous studies have demonstrated nonsteroidal antiinflammatory drug treatment in early lactation had a positive impact on whole-lactation milk production in older cows. The objective of this study was to evaluate proliferative, transcriptional, and epigenetic changes in the mammary gland that could explain increased production responses due to nonsteroidal antiinflammatory drug treatment. Sodium salicylate (SAL; 125 g/d) or water (CON) were administered via oral drench to multiparous Holstein cows (n = 8/treatment) once daily for 3 d beginning approximately 24 h after parturition, and mammary tissue was collected on d 1, 4, and 45 postpartum. Day 1 tissue was collected immediately preceding the initial drench, and d 4 tissue was collected 24 h following the final drench. Blood was collected twice weekly and analyzed for plasma glucose, insulin, β-hydroxybutyrate, free fatty acids, and prolactin. Cows were milked twice daily until d 7 of lactation, and thrice daily for the remainder of the study. Total RNA extracted from tissue was deep-sequenced and analyzed for differential gene expression using DESeq2. We detected no treatment effect on milk yield or plasma metabolites through 45 d of lactation; additionally, no change in mammary epithelial cell proliferation was detected when assessed by Ki67 labeling. Comparison of SAL versus CON revealed that only 16 of 18,286 genes were differentially expressed (false discovery rate <0.1) in mammary tissue collected on d 45, whereas no differentially expressed genes due to treatment were detected on d 1 or 4. Analysis of transcriptional differences over time showed downregulation of pathways related to immune cell recruitment and differentiation, and extensive overlap with pathways related to cholesterol synthesis and liver X receptor signaling. Global DNA methylation of mammary tissue was decreased for CON compared with SAL. Transcriptome analysis emphasized extensive involvement of immune-related signaling pathways in the switch from lactogenesis to galactopoiesis, and changes in methylation with SAL treatment merit future investigation into epigenetic effects on milk production.

Invited review: Mechanisms of hypophagia during disease

Suppression of appetite, or hypophagia, is among the most recognizable effects of disease in livestock, with the potential to impair growth, reproduction, and lactation. The continued evolution of the field of immunology has led to a greater understanding of the immune and endocrine signaling networks underlying this conserved response to disease. Inflammatory mediators, especially including the cytokines tumor necrosis factor-α and interleukin-1β, are likely pivotal to disease-induced hypophagia, based on findings in both rodents and cattle. However, the specific mechanisms linking a cytokine surge to decreased feeding behavior are more difficult to pin down and likely include direct effects on appetite centers in the brain, alteration of gastric motility, and modulation of other endocrine factors that influence appetite and satiety. These insights into the mechanisms for disease-induced hypophagia have great relevance for management of neonatal calves, mature cows transitioning to lactation, and cows experiencing mastitis; however, it is not necessarily the case that increasing feed intake by any means possible will improve health outcomes for diseased cattle. We explore conflicting effects of hypophagia on immune responses, which may be impaired by the lack of specific substrates, versus apparent benefits for controlling the growth of some pathogens. Anti-inflammatory strategies have shown promise for promoting recovery of feed intake following some conditions but not others. Finally, we explore the potential for early disease detection through automated monitoring of feeding behavior and consider which strategies may be implemented to respond to early hypophagia.

Invited review: The influence of immune activation on transition cow health and performance-A critical evaluation of traditional dogmas

The progression from gestation into lactation represents the transition period, and it is accompanied by marked physiological, metabolic, and inflammatory adjustments. The entire lactation and a cow's opportunity to have an additional lactation are heavily dependent on how successfully she adapts during the periparturient period. Additionally, a disproportionate amount of health care and culling occurs early following parturition. Thus, lactation maladaptation has been a heavily researched area of dairy science for more than 50 yr. It was traditionally thought that excessive adipose tissue mobilization in large part dictated transition period success. Further, the magnitude of hypocalcemia has also been assumed to partly control whether a cow effectively navigates the first few months of lactation. The canon became that adipose tissue released nonesterified fatty acids (NEFA) and the resulting hepatic-derived ketones coupled with hypocalcemia lead to immune suppression, which is responsible for transition disorders (e.g., mastitis, metritis, retained placenta, poor fertility). In other words, the dogma evolved that these metabolites and hypocalcemia were causal to transition cow problems and that large efforts should be enlisted to prevent increased NEFA, hyperketonemia, and subclinical hypocalcemia. However, despite intensive academic and industry focus, the periparturient period remains a large hurdle to animal welfare, farm profitability, and dairy sustainability. Thus, it stands to reason that there are alternative explanations to periparturient failures. Recently, it has become firmly established that immune activation and the ipso facto inflammatory response are a normal component of transition cow biology. The origin of immune activation likely stems from the mammary gland, tissue trauma during parturition, and the gastrointestinal tract. If inflammation becomes pathological, it reduces feed intake and causes hypocalcemia. Our tenet is that immune system utilization of glucose and its induction of hypophagia are responsible for the extensive increase in NEFA and ketones, and this explains why they (and the severity of hypocalcemia) are correlated with poor health, production, and reproduction outcomes. In this review, we argue that changes in circulating NEFA, ketones, and calcium are simply reflective of either (1) normal homeorhetic adjustments that healthy, high-producing cows use to prioritize milk synthesis or (2) the consequence of immune activation and its sequelae.

Sodium salicylate reduced mRNA abundance of hypoxia-associated genes in MAC-T cells

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Sodium salicylate decreased abundance of transcripts involved in mammary development.

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Knockdown of HIF-1α did not prevent hypoxia-induced glucose transporter 1 expression.

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Few interactions between hypoxia and sodium salicylate were observed.

Hypoxia is an oxygen deficiency commonly found in growing tissues and is speculated to occur in the rapidly developing mammary gland in peripartum dairy cattle. Low oxygen concentrations can activate hypoxia-inducible factor-1 (HIF-1), which increases transcription of genes involved in angiogenesis (VEGFA) and glucose transport (GLUT1), among other processes. The mRNA stability of these genes is positively regulated by heterogeneous nuclear ribonucleoprotein D (HNRNPD; also known as AUF1). In our previous research, postpartum administration of sodium salicylate (SS) increased whole-lactation milk yield in multiparous cows but tended to reduce milk yield in primiparous cows. Because rapid mammary tissue development likely occurs in cows approaching first lactation, we hypothesized that SS inhibited the activation of HIF-1α and decreased transcription of downstream targets. MAC-T cells were treated with SS (100 μM) or control medium before incubation under either hypoxic (1% O₂) or normoxic conditions for 12 h. Additionally, cells were transfected with either HIF1A small interfering RNA (siRNA) or a scrambled siRNA negative control 48 h before hypoxia treatments. HIF1A, GLUT1, VEGFA, and HNRNPD were quantified relative to the internal control gene NENF. Transcript abundance was assessed using a linear mixed model with the fixed effects of SS, hypoxia, siRNA, and all 2- and 3-way interaction terms and the random effect of plate nested within hypoxia. Treatment with SS interacted with hypoxia for GLUT1, as SS reduced GLUT1 when MAC-T cells were cultured in normoxic conditions; however, no effect of SS was found in hypoxia-treated cells. Regardless of oxygen status, SS reduced HNRNPD and tended to decrease VEGFA mRNA relative to untreated cells. Hypoxia increased GLUT1, yet no effect was observed on VEGFA or HNRNPD. Small interfering RNA knocked down HIF1A, but no effect was found on GLUT1, VEGFA, or HNRNPD. In conclusion, SS reduced transcript abundance of genes involved with mammary gland development but generally did not interact with oxygen status.

Prolonged, low-grade inflammation in the first week of lactation: Associations with mineral, protein, and energy balance markers, and milk yield, in a clinically healthy Jersey cow cohort

Our objectives were to perform a proof-of-concept study to assess the association of a prolonged inflammatory state (based on a continually elevated haptoglobin concentration at the end of the first week after parturition) with mineral, protein, and energy balance markers in the first 2 wk after parturition, and milk production in the first 60 d of lactation in clinically healthy cows. We conducted a cohort study in 1 herd in west Texas that was milking Jersey and Jersey-Holstein crosses. Only multiparous Jersey cows were eligible for enrollment. Cows were classified as having or not having elevated haptoglobin concentrations based on plasma concentrations evaluated on d 4 and 7 postpartum. We used median concentrations of haptoglobin in the reference population (i.e., before the exclusion of cows diagnosed with clinical diseases) as the limits for categorizing cows into 2 groups: cows with plasma haptoglobin concentrations greater than the median values on both d 4 (0.49 g/L) and 7 (0.35 g/L) had continually elevated haptoglobin (with eHp); and cows with plasma haptoglobin concentrations lower than or equal to the median values of the reference population on d 4 or 7 did not have continually elevated haptoglobin (without eHp). Next, cows with clinical diseases in the first 2 wk of the postpartum period were excluded, so that 233 cows remained for the final analyses. Evaluated outcomes were average daily milk production across the first 60 d of lactation, plasma Ca, Mg, and glucose concentrations on d 1, 2, 3, 4, 5, 7, 10, and 14 postpartum, and β-hydroxybutyrate (BHB), nonesterified fatty acids (NEFA), fructosamine, albumin, urea, and creatinine concentrations on d 3, 5, 7, 10, and 14 postpartum. Rectal temperatures measured on d 4, 7, and 10 postpartum were also analyzed. We performed statistical analyses using linear mixed models while accounting for the repeated effect of sampling time (plasma analytes and rectal temperature models) and weekly milk test (milk production model). Cows with eHp had lower plasma Ca concentrations in the first 2 wk after calving, but no differences in Mg, BHB, NEFA, glucose, or rectal temperatures compared to cows without eHp. Cows with eHp had lower plasma fructosamine, albumin, and urea concentrations in a time-dependent manner. They also had lower milk production (2.3 kg/d less than cows without eHp in the first 60 DIM). Our study demonstrated that 25% of cows without clinical disorders in the first 2 wk after parturition had continually elevated haptoglobin concentrations at d 7 after parturition relative to d 4, suggestive of a prolonged, low-grade systemic inflammatory state. More observational studies are needed to more fully characterize the duration of prolonged postpartum subclinical inflammation in cows without clinical diseases, as well as its long-term effects, and to evaluate the use of other potential markers of systemic inflammation to describe this disorder.

Effects of postpartum acetylsalicylic acid on uterine diseases and reproductive performance in dairy cattle

Uterine diseases are some of the most prevalent and costly diseases for the dairy industry. It has been reported that an exacerbated and prolonged inflammatory response around calving can increase the risk of developing metritis, which subsequently can impair production and fertility in dairy cows. The objective of this study was to assess the effects of 2 oral administrations of acetylsalicylic acid 24 h apart on the incidence of uterine diseases [i.e., retained fetal membranes, clinical metritis, clinical endometritis) and reproductive performance [i.e., days in milk to conception, number of services to conception, proportion of cows pregnant at first service, proportion of abortion at first service (ABRT)] in dairy cows after calving. Cows from one dairy farm (n = 246) located in central Pennsylvania were included in this study. Animals were blocked by parity and randomly assigned to 1 of 2 groups: (1) ASA (n = 121): within ~12 h after parturition, cows received 2 treatments with acetylsalicylic acid (ASA; 200 mg/kg, 4 boluses) 24 h apart; or (2) UNT (n = 125): cows remained untreated. Clinical metritis was assessed at 7 ± 3 and 14 ± 3 d in milk (DIM) using a Metricheck device (Simcro Tech Ltd., Hamilton, New Zealand). Cows that presented a fetid, red-brownish, watery vaginal discharge were classified as having clinical metritis. Clinical endometritis was assessed through ultrasonography and defined as presence of hyperechoic fluid (>3 mm) in the uterus lumen at 50 ± 10 DIM. The incidence of retained fetal membranes was defined as the failure of expulsion of the placenta within 24 h after calving and recorded by farm personnel. The data were analyzed using the MIXED and GLIMMIX procedures of SAS (SAS Institute Inc., Cary, NC) as a randomized complete block design. A lower proportion of cows treated with acetylsalicylic acid developed clinical metritis at 7 ± 3 DIM (ASA = 34.97 ± 5.57%; UNT = 57.21 ± 5.80%) and tended to develop clinical endometritis at 50 ± 10 DIM (ASA = 3.84 ± 2.67%; UNT = 13.61 ± 5.23%) compared with cows that remained untreated. Cows treated with acetylsalicylic acid tended to require 18 d less to conceive compared with UNT cows (ASA = 125.63 ± 8.21 d; UNT = 143.44 ± 6.28 d). Furthermore, there was a tendency for a treatment × ABRT interaction, whereby ASA cows that aborted at first service tended to conceive 35 d sooner compared with UNT cows that aborted at first service (ASA = 151.42 ± 15.90 d; UNT = 186.38 ± 11.84 d). Although there was no difference in pregnancy per AI at first service between treatment groups (ASA = 23.88 ± 7.92%; UNT = 17.93 ± 6.31%), the proportion of cows aborting at first service in the ASA group tended to be lower than that in the UNT group (ASA = 1.03 ± 1.06%; UNT = 6.04 ± 2.62%). Results from this study suggest that a short-duration acetylsalicylic acid treatment after calving may decrease the incidence of uterine diseases and improve reproductive success in cows that aborted at first service in dairy cattle.

Effect of uncouplers of oxidative phosphorylation on metabolism of propionate in liver explants from dairy cows

Our objective was to determine the effects of uncouplers of oxidative phosphorylation on the metabolism of propionate in liver tissue of dairy cows in the postpartum period. A total of 8 primiparous dairy cows were biopsied for liver tissue explants in 2 block-design experiments. Cows were 5.9 ± 2.8 (mean ± SD) days in milk, and the 2 experiments were run concurrently. Treatments for experiment 1 were 10 μM 2,4-dinitrophenol methyl ether (DNPME) or propylene carbonate (vehicle control). Treatments for experiment 2 were 5 mM sodium salicylate (SAL) or no treatment (control). Explants were incubated in 2.5 mM [¹³C₃]propionate with treatments and terminated after 0.5, 15, and 60 min of exposure to tracer. Treatment with DNPME had no effects on measured metabolites compared with control. Treatment with SAL increased total ¹³C% enrichment of succinate (3.03 vs. 2.45%), but tended to decrease total ¹³C% enrichment of fumarate (2.86 vs. 3.10%) and decreased total ¹³C% enrichment of malate (3.96 vs. 4.58%) compared with the control. Treatment with DNPME appeared to have no effects on hepatic propionate metabolism, and treatment with SAL may impair the succinate dehydrogenase reaction.

Reproductive Tract Infections in Dairy Cows: Can Probiotics Curb Down the Incidence Rate?

Postpartum uterine diseases are common in dairy cows and are a great concern for the dairy industry as they are associated with various consequences, including lower fertility, lower milk yield, and an overall negative impact on the host health. An infected uterus is a source of bacterial compounds and cytokines that spill into the systemic circulation, spreading inflammation to other organs. In this review article, we discuss a short overview of the anatomy of the reproductive tract of dairy cows and several infectious diseases of the uterus including metritis, endometritis, and pyometra. Additionally, we discuss the microbiome of the reproductive tract in health and during uterine diseases. As well, diagnostic criteria for metritis and endometritis and contributing factors for increased susceptibility to metritis infection are important topics of this review. To better understand how the uterus and reproductive tract respond to bacterial pathogens, a section of this review is dedicated to immunity of the reproductive tract. Both the innate and adaptive immunity systems are also discussed. We conclude the review with a factual discussion about the current treatments of uterine diseases and the new developments in the area of application of probiotics for uterine health. Mechanisms of actions of probiotics are discussed in detail and also some applications to prevent uterine infections in dairy cows are discussed.

Effects of metritis treatment strategies on health, behavior, reproductive, and productive responses of Holstein cows

Our objectives were to compare the effects of ceftiofur crystalline free acid (CCFA) and ampicillin trihydrate (AMP) treatments of cows diagnosed with metritis on uterine health, behavior, reproductive, and productive responses. A controlled randomized clinical trial was designed. Metritis was defined as vaginal discharge (VD) = 5 (fetid, watery, red/brown) within 21 d in milk (DIM) and rectal temperature (RT) <39.5°C, whereas VD = 5 and RT ≥39.5°C was defined as puerperal metritis. On the day of diagnosis (d 0), cows were paired by parity and severity of metritis (metritis vs. puerperal metritis) and assigned randomly to the AMP and CCFA treatments. Cows enrolled in the AMP (n = 308) treatment were moved to a nonsalable-milk pen, where they were treated once daily for 5 d, and were moved back to their original pen 72 h after the last treatment (d 7). Cows enrolled in the CCFA (n = 310) treatment remained in their original pen and received 2 treatments of CCFA, 72 h apart. Rectal temperature was measured daily from d 0 to 6 and on d 11. Vaginal discharge was evaluated on d 4, 6, and 11 to assess cure. Cure was defined as the absence of treatment with additional antimicrobial before experiment d 11, VD <5, and RT <39.5°C. Cows were examined at 28 ± 3 DIM for purulent VD (PVD) and at 35 ± 3 DIM for cytological endometritis. Pregnancy was diagnosed at 40 ± 3 and 60 ± 7 d after first and second artificial inseminations. Cure of metritis did not differ between treatments on d 11 (AMP = 64.6 ± 3.1, CCFA = 63.5 ± 3.1%). Cows treated with AMP had greater RT from experiment d 1 to 6 compared with cows treated with CCFA (AMP = 39.1 ± 0.02, CCFA = 39.0 ± 0.02°C). Cows in the AMP treatment had greater prevalence of PVD at 28 ± 3 DIM (AMP = 82.6 ± 2.3, CCFA = 74.4 ± 2.7%) and tended to have greater prevalence of cytological endometritis at 35 ± 3 DIM (AMP = 77.8 ± 6.2 vs. CCFA = 61.7 ± 7.5%) than CCFA-treated cows. Treatment did not affect the hazard of pregnancy among multiparous cows; however, among primiparous cows, CCFA treatment reduced the hazard of pregnancy and increased the median days to pregnancy (AMP = 145 vs. CCFA = 169 d). Finally, average daily milk yield up to 14 wk postpartum was not affected by treatment (AMP = 38.0 ± 0.4, CCFA = 37.5 ± 0.4 kg). We conclude from the current experiment that CCFA was more effective in reducing RT and improving uterine health of metritic cows; however, the improved hazard of pregnancy of primiparous cows treated with AMP is important and warrants further investigation.

Outcomes from Experimental Testing of Nonsteroidal Anti-Inflammatory Drug (NSAID) Administration during the Transition Period of Dairy Cows

Simple Summary

The treatment of dairy cows with nonsteroidal drugs is applied experimentally to investigate the relevance of inflammation during the periparturient period. Despite appearing healthy, dairy cows throughout the transition period and mainly after parturition can develop a pro-inflammatory status that may negatively influence milk production and cows’ health. The administration of nonsteroidal anti-inflammatory drugs (NSAIDs) has been demonstrated to have both positive or negative effects on health and milk production, depending on the type of inhibition mechanism, the dose administered and the cows’ lactation numbers. At present, the safety and efficacy of NSAIDs have not been irrefutably demonstrated; therefore, their use to improve metabolic and inflammatory status, as well as milk production and cow health after parturition, should be carefully evaluated.

Abstract

During the transition period, dairy cows experience great physiological stress caused by changes in metabolism and in the immune and endocrine systems. A pro-inflammatory state is another difficulty faced by even apparently healthy animals. The most significant negative consequences of inflammation in dairy cows are substantial impairment of milk production and deleterious effects on cows’ health in extreme cases. Nonetheless, a certain degree of inflammation is necessary to sustain physiological adaptations. In recent years, many studies have attempted to determine whether the use of nonsteroidal anti-inflammatory drugs (NSAID) in the transition period of dairy cows could positively affect milk production and cows’ health by controlling the inflammation status. This literature indicates that NSAIDs that act as preferential inhibitors of cyclooxygenase-1 (COX-1) activity show important side effects (e.g., increased risk of retained placenta, culling, or metritis) even if milk production is, on average, ameliorated. In contrast, preferential inhibitors of cyclooxygenase-2 (COX-2) activity have overall positive effects on cows’ health, with potential beneficial effects on milk production. Furthermore, it is important to note that with certain NSAID treatments, milk discarding is mandatory to prevent contamination with drug residues, but increased milk production can compensate for the loss of milk revenue during the withdrawal period.

Administration of acetylsalicylic acid after parturition in lactating dairy cows under certified organic management: Part II. Biomarkers of nociception, inflammation, and stress

The objective was to assess the effect of oral administration of acetylsalicylic acid after calving on the concentrations of substance P (SP), haptoglobin (HP), and cortisol in lactating dairy cows. Holstein dairy cows (n = 152) from 3 organic herds were included. At parturition, cows were blocked by parity [multiparous (MULT) and primiparous (PRIM)] and calving ease [eutocia (EUT) and dystocia (DYS)] and were randomly assigned to 1 of 2 treatment groups: aspirin (ASP; n = 76), in which within 12 h after parturition cows received 4 treatments with acetylsalicylic acid (100 mg/kg; 2 boluses) at 12-h intervals, or placebo (PLC; n = 76), in which within 12 h after parturition cows received 4 consecutive treatments with gelatin capsules (2 capsules) containing water 12 h apart. Blood samples were collected immediately before treatment and at 12, 24, 36, 48, and 168 h (7 DIM) for assessment of circulating concentration of SP, HP, and cortisol. Based on farm records, cows were classified in the following clinical disease categories: no clinical disease event (NO-EVT), a single clinical disease event (SI-EVT), and more than 1 clinical disease event (MU-EVT). The study data were analyzed as a randomized complete block design using mixed multiple linear and logistic regression models. With regard to HP, there was a tendency for an interaction between treatment and parity, where MULT cows treated with ASP had lower concentration of HP compared with MULT cows treated with PLC (ASP = 124.33 ± 6.83 µg/mL; PLC = 143.9 ± 7.24 µg/mL). Analysis by calving ease showed that cows with DYS had higher concentrations of HP (DYS = 159.17 ± 5.97 µg/mL; EUT = 138.72 ± 6.22 µg/mL) and SP (only at 168 h; DYS = 64.99 pg/mL, 95% confidence interval, CI: 2.68-2.81; EUT = 60.33 pg/mL, 95% CI: 2.91-3.06) after calving compared with EUT cows. Regardless of treatment, PRIM cows had higher concentrations of SP (MULT = 55.11 pg/mL, 95% CI: 1.27-1.30; PRIM = 57.62 pg/mL, 95% CI: 1.99-2.06), HP (MULT = 134.14 ± 4.96 µg/mL; PRIM = 163.75 ± 7.76 µg/mL), and cortisol (MULT = 18.65 µg/mL, 95% CI: 1.02-1.05; PRIM = 21.92 µg/mL, 95% CI: 1.67-1.74) compared with MULT cows. In addition, cows that experienced SI-EVT or MU-EVT had higher concentrations of HP (NO-EVT = 134.13 ± 5.95 µg/mL; SI-EVT = 142.68 ± 7.32 µg/mL; MU-EVT = 170.03 ± 9.42 µg/mL) and cortisol (NO-EVT = 17.86 µg/mL, 95% CI: 1.20-1.24; SI-EVT = 21.01 µg/mL, 95% CI: 1.61-1.67; MU-EVT = 22.01 µg/mL, 95% CI: 2.08-2.18) compared with cows with NO-EVT recorded. Results from this study suggest that a short-duration anti-inflammatory therapy after calving reduced HP in MULT cows but may not have effects on SP and cortisol concentrations. Calving ease and parity affected the concentrations of markers of inflammation, nociception, and stress regardless of treatment. Further research is warranted to assess anti-inflammatory strategies aimed at decreasing inflammation and stress in DYS and PRIM cows and therefore improve welfare and performance of these high-priority groups.

Effects of postpartum acetylsalicylic acid on metabolic status, health, and production in lactating dairy cattle

The transition period is one of the most challenging times for dairy cattle. Previous research suggests that treatment of postpartum cows with anti-inflammatory drugs may decrease pain and inflammation, enhancing cow welfare and performance during this challenging period. However, these strategies involve numerous time-consuming interventions, which require extra labor and do not fit modern farm logistics. The objective of this experiment was to assess the effects of acetylsalicylic acid (ASA) every 24 h for 2 d after calving on (1) daily milk yield, daily milk conductivity, and daily rumination during the first 60 days in milk (DIM), and 305-d mature-equivalent milk, milk fat, and milk protein yields, (2) body condition score, β-hydroxybutyrate (BHB), and haptoglobin, and (3) incidence of clinical diseases during the first 60 DIM. Dairy cows (n = 246) from a dairy farm located in Pennsylvania were enrolled in this experiment. Cows were blocked by parity and assigned randomly to 1 of 2 treatments: (1) ASA (n = 121), in which cows received 2 treatments with ASA (200 mg/kg; 4 boluses), the first within 12 h after parturition and the second 24 h later; or (2) untreated (UNT; n = 125), in which cows remained untreated. Blood samples were collected at 30 ± 6 h, 7 ± 3 d, and 14 ± 3 d after calving to measure BHB and haptoglobin concentrations. Body condition score was assessed at enrollment, 7 ± 3 DIM, 14 ± 3 DIM, and 50 ± 10 DIM. Furthermore, incidences of diseases, daily rumination, daily milk yield, and daily milk conductivity during the first 60 DIM and 305-d mature-equivalent milk, milk fat, and milk protein yields were collected from on-farm computer records. The data were analyzed using mixed multiple linear and logistic regression models as a randomized complete block design. Multiparous cows treated with ASA produced 1.64 kg/d more milk compared with multiparous cows that remained untreated (ASA = 41.66 ± 0.88 kg/d; UNT = 40.02 ± 0.81 kg/d) during the first 60 DIM. There was no difference in daily milk conductivity and rumination between treatments. Cows treated with ASA had lower concentration of BHB (ASA = 1.16 ± 0.64 mmol/L; UNT = 1.23 ± 0.80 mmol/L) during the first 14 ± 3 DIM and had higher body condition score within the first 50 ± 10 DIM compared with cows that remained UNT. There were no differences in circulating concentrations of haptoglobin between treatments. These results support previous findings showing that the use of anti-inflammatory drugs after calving may increase milk production and affect the metabolic status of dairy cows.

Review: Following the smoke signals: inflammatory signaling in metabolic homeostasis and homeorhesis in dairy cattle

Inflammatory cascades are a critical component of the immune response to infection or tissue damage, involving an array of signals, including water-soluble metabolites, lipid mediators and several classes of proteins. Early investigation of these signaling pathways focused largely on immune cells and acute disease models. However, more recent findings have highlighted critical roles of both immune cells and inflammatory mediators on tissue remodeling and metabolic homeostasis in healthy animals. In dairy cattle, inflammatory signals in various tissues and in circulation change rapidly and dramatically, starting just prior to and at the onset of lactation. Furthermore, several observations in healthy cows point to homeostatic control of inflammatory tone, which we define as a regulatory process to balance immune tolerance with activation to keep downstream effects under control. Recent evidence suggests that peripartum inflammatory changes influence whole-body nutrient flux of dairy cows over the course of days and months. Inflammatory mediators can suppress appetite, even at levels that do not induce acute responses (e.g. fever), thereby decreasing nutrient availability. On the other hand, inhibition of inflammatory signaling with non-steroidal anti-inflammatory drug (NSAID) treatment suppresses hepatic gluconeogenesis, leading to hypoglycemia in some cases. Over the long term, though, peripartum NSAID treatment substantially increases peak and whole-lactation milk synthesis by multiparous cows. Inflammatory regulation of nutrient flux may provide a homeorhetic mechanism to aid cows in adapting to rapid changes in metabolic demand at the onset of lactation, but excessive systemic inflammation has negative effects on metabolic homeostasis through inhibition of appetite and promotion of immune cell activity. Thus, in this review, we provide perspectives on the overlapping regulation of immune responses and metabolism by inflammatory mediators, which may provide a mechanistic underpinning for links between infectious and metabolic diseases in transition dairy cows. Moreover, we point to novel approaches to the management of this challenging phase of the production cycle.

Effect of anti-inflammatory treatment on systemic inflammation, immune function, and endometrial health in postpartum dairy cows

Systemic inflammation (SI) is increasingly studied in several species because it may be central in many metabolic disturbances and be a risk factor for clinical disease. This proof-of-concept study evaluated the effects of the anti-inflammatory drug meloxicam on markers of SI and energy metabolism, polymorphonuclear neutrophil (PMN) function, and endometritis in clinically healthy postpartum dairy cows. Cows received meloxicam (0.5 mg/kg of body weight; n = 20) once daily for 4 days (10-13 days postpartum) or were untreated (n = 22). Blood samples were collected -7, 1, 3, 5, 7, 10, 11, 12, 13, 14, 18, 21, 28, and 35 days relative to calving to measure serum concentrations of metabolic and inflammatory markers. Function of peripheral blood PMN were evaluated at 5, 10, 14, and 21, and proportion of PMN in endometrial cytology were performed at 5, 10, 14, 21, 28 and 35 days postpartum. Meloxicam decreased serum haptoglobin from the second until the last day of treatment, and improved indicators of energy metabolism (lesser β-hydroxybutyrate and greater insulin-like growth factor-1 during treatment, and greater glucose at the end of treatment than control cows). This improved PMN function at 14 days postpartum, but the endometrial inflammatory status was not affected.

Modulation of immune function in the bovine uterus peripartum

There is a high risk of clinical or subclinical reproductive tract disease in the postpartum period in dairy cows. An integrated process of adaptive events should occur synchronously, including a robust but well-regulated immune response in the uterus. Failure of this process may result in reproductive tract inflammatory disease. Up to half of postpartum dairy cows are affected by metritis, purulent vaginal discharge (PVD), or subclinical endometritis. After parturition there is damage to the birth canal, the superficial layer of the endometrium is naturally wounded, and essentially all dairy cows have bacterial contamination in the uterus. Neutrophils are the most abundant type of inflammatory cell and the main line of defence against infection in the uterus. A prompt influx of neutrophils is associated with uterine health. Avoidance of clinical disease (metritis and PVD) depends in large part on how effective the immune response is at limiting the burden and effects of bacterial pathogens, while the occurrence of subclinical endometritis is more a function of avoiding excessive or persistent inflammation. Glucose supply, hypocalcemia, lipid mobilization from body fat, ketosis, and the flux of pro-inflammatory cytokines influence immune response and change rapidly and variably among individual cows. Effective but well-regulated inflammatory response will be favoured by best management practices for transition cows, but specific interventions to modulate immune response to prevent uterine disease remain developmental.

Diet starch concentration and starch fermentability affect markers of inflammatory response and oxidant status in dairy cows during the early postpartum period

Our objective was to evaluate the effects of diet starch concentration and starch fermentability on inflammatory response markers and oxidant status during the early postpartum (PP) period and its carryover effects. Fifty-two multiparous Holstein cows were used in a completely randomized block design experiment with a 2 × 2 factorial arrangement of treatments. Treatments were starch concentration and starch fermentability of diets; diets were formulated to 22% (low starch, LS) or 28% (high starch, HS) starch with dry-ground corn (DGC) or high-moisture corn (HMC) as the primary starch source. Treatments were fed from 1 to 23 d PP and then switched to a common diet until 72 d PP to measure carryover (CO) effects. Treatment period (TP) diets were formulated to 22% forage neutral detergent fiber and 17% crude protein. The diet for the CO period was formulated to 20% forage neutral detergent fiber, 17% crude protein, and 29% starch. Coccygeal blood was collected once a week during the TP and every second week during the CO period. Liver and adipose tissue biopsies were performed within 2 d PP and at 20 ± 3 d PP. Blood plasma was analyzed for concentrations of albumin, haptoglobin, reactive oxygen and nitrogen species (RONS), and antioxidant potential (AOP), with lipopolysaccharide-binding protein (LBP) and TNFα evaluated during the TP only. Oxidative stress index (OSi) was calculated as RONS/AOP. Abundance of mRNA from genes involved in inflammation and glucose metabolism in liver and genes involved in lipogenesis in adipose tissue were determined. Data were analyzed separately for the TP and CO periods. During the TP, treatments interacted to affect concentrations of TNFα, haptoglobin, and LBP, with HMC increasing their concentrations for HS (9.38 vs. 7.45 pg/mL, 0.45 vs. 0.37 mg/mL, and 5.94 vs. 4.48 μg/mL, respectively) and decreasing their concentrations for LS (4.76 vs. 12.9 pg/mL, 0.27 vs. 0.41 mg/mL, and 4.30 vs. 5.87 μg/mL, respectively) compared with DGC. Effects of treatments diminished over time for LBP and haptoglobin with no differences by the end of the TP and no main CO effects of treatment for haptoglobin. The opposite treatment interaction was observed for albumin, with HMC tending to decrease its concentration for HS (3.24 vs. 3.34 g/dL) and increase its concentration for LS (3.35 vs. 3.29 g/dL) compared with DGC, with no carryover effect. Feeding DGC increased the OSi during the first week of the TP compared with HMC, with this effect diminishing over time; during the CO period HMC increased OSi for HS and decreased it for LS compared with DGC, with this effect diminishing toward the end of CO. Feeding HMC increased the abundance of genes associated with inflammation and gluconeogenesis in liver for HS and decreased it for LS compared with DGC. Feeding HS increased the mRNA abundance of genes associated with adipose tissue lipogenesis compared with LS. Results during the TP suggest that feeding LS-DGC and HS-HMC elicited a more pronounced inflammatory response and induced an upregulation of genes associated with inflammation and gluconeogenesis in liver, without effects on OSi, but effects on plasma markers of inflammation diminished during the CO period.

Proteome dataset of subcutaneous adipose tissue from postpartum cows treated with sodium salicylate

This article contains raw and processed data related to research published by Takiya et al. [1]. Literature have shown that treatment with the nonsteroidal anti-inflammatory agent sodium salicylate (SS) during the first days postpartum in dairy cows increased lactation performance [2], and tended to alter glucose metabolism [3]. Yet, the specific effects of systemic SS treatment on the proteome of the adipose tissue (AT) and on the inflammatory process in AT of postpartum cows is unknown. Subcutaneous AT samples were collected at 7 d of lactation from control cows (n = 5) and from cows treated with 2.3 g/L SS (n = 5) via drinking water during the first 7 d of lactation. Protein extraction and liquid chromatography-mass spectrometry were performed to obtain proteomics data. Differential abundance of proteins was determined through MS1 intensity based label-free method. Proteomics analysis generated a novel dataset consisted of 1422 proteins, 80 (5.6%) of which were differentially abundant [fold change ± 1.5, P < 0.05 2-way ANOVA] when comparing control and SS-treated cows. The present dataset of subcutaneous AT proteome from postpartum dairy cows treated with SS can be used as a reference for any research involving nonsteroidal anti-inflammatory agent treatment in dairy cows or in comparative research between species.

The effect of uncouplers of oxidative phosphorylation on the feeding behavior of lactating dairy cows

Our objective was to determine the effects of uncouplers of oxidative phosphorylation on feeding behavior of lactating dairy cows. We hypothesized that uncouplers of oxidative phosphorylation would increase meal size and meal length and performed 2 experiments to test our hypothesis. In experiment 1, 4 late-lactation cows (345 ± 48.4 d in milk; mean ± SD) were administered a daily intrajugular injection of either 10 mg/kg of BW^0.75 of 2,4-dinitrophenol methyl ether (DNPME) and propylene carbonate or propylene carbonate (control; CON) in a crossover design with 2-d periods. In experiment 2, 8 early-lactation cows (11.3 ± 0.89 d in milk) were administered a daily intrajugular injection via jugular catheter of either 50 mg/kg of BW of sodium salicylate (SAL) and saline or saline (control; CON) in a crossover design with 1-d periods. Feeding behavior was recorded by a computerized data acquisition system and analyzed for the first 4 h after access to feed within 15 min of treatment for both experiments. Neither DNPME nor SAL affected meal size over the first 4 h after access to feed. However, DNPME increased meal length by 6.4 min (26.3 vs. 19.9 min) and tended to decrease the number of meals (2.55 vs. 2.78 meals/4 h) over the first 4 h after access to feed compared with CON. Both DNPME and SAL decreased eating rate over the first 4 h after access to feed compared with their respective controls (0.10 vs. 0.12 kg/min for DNPME vs. CON; 0.06 vs. 0.07 kg/min for SAL vs. CON). Lack of treatment effects on meal size may have been caused by increased rate of oxidation of fuels compensating for the disruption of oxidative phosphorylation.

Feed restriction to induce and meloxicam to mitigate potential systemic inflammation in dairy cows before calving

Most dairy cows experience a transient decrease in feed intake in the 1 to 2 wk before calving, which has been associated with systemic inflammation (SI), indicated by increased blood haptoglobin (Hp) concentration. We aimed to characterize the association between prepartum decrease in feed intake and the onset of SI and, if present, the ability of meloxicam (MEL), a non-steroidal anti-inflammatory drug, to mitigate SI. Holstein cows (n = 45) were assigned to control (n = 13), feed restriction (FR) untreated (FR-U; n = 15), and FR treated with MEL (FR-T; n = 17) groups. Daily feed intake was measured from -22 d from expected parturition until 35 d postpartum. Control cows were fed ad libitum, whereas FR-U and FR-T cows were reduced to 60% of their average intake for 4 consecutive days (-15 to -12 d from expected calving). The FR-T cows received MEL (0.5 mg/kg of body weight) once daily for 4 consecutive days (-13 to -10 d from expected calving). Blood samples were collected -22, -15, -14, -13, -12, -10, -7, -5, -3, 0, 1, 3, 5, 7, 15, 22, and 35 d relative to calving to measure serum concentrations of total calcium, total protein, albumin, globulin, cholesterol, urea, glucose, gamma-glutamyl transferase, aspartate aminotransferase, glutamate dehydrogenase, β-hydroxybutyrate, nonesterified fatty acids, Hp, and insulin-like growth factor-1. Serum concentrations of lipopolysaccharide-binding protein were measured -22, -15, -14, -13, -12, and -10 d from expected calving. Simplified glucose tolerance tests were performed on -15, -12, -5, 1, and 5 d relative to calving. Mixed linear regression models were used to assess the effects of FR and MEL on each metabolite. The interaction between treatment group and blood sampling day was forced into each model. All models accounted for body condition score, parity, and the cow as a random effect. Nonesterified fatty acids concentrations in both the FR-U and FR-T groups significantly increased from the second until the last day of FR. Feed restriction increased urea concentrations compared with the control group on -14 d but decreased urea concentrations on -10 d from expected calving. Control cows had greater β-hydroxybutyrate concentrations compared with FR cows on 15, 21, and 35 d postpartum. For all other metabolites, no differences were found. This model of FR produced substantial fat mobilization but based on serum Hp and lipopolysaccharide-binding protein concentrations did not generate measurable SI; therefore, we were unable to evaluate the ability of MEL to mitigate SI.

Transcriptomic analysis of circulating neutrophils in metabolically stressed peripartal grazing dairy cows

The high metabolic demand during the transition into lactation places cows at greater risk of metabolic and infectious disease than at any other time in their lactation cycle. Additionally, a change occurs in the innate immune response during this period, which contributes to increased risk of disease. In the current study, we compared the transcriptomes of neutrophils from dairy cows divergent in their metabolic health post-calving. Cows (n = 5 per risk group) were selected from a parent experiment (n = 45 cows). Those with high or low concentrations of plasma nonesterified fatty acids, plasma β-hydroxybutyrate, and liver triacylglycerol in both wk 1 and 2 were deemed to be at "high risk" (HR) or "low risk" (LR) of metabolic dysfunction, respectively. Circulating neutrophils were isolated at 3 time points during the transition period (d 0 and wk 1 and 4 post-calving), and gene expression was analyzed using RNA sequencing. Differential gene expression between the risk groups was determined using edgeR (http://bioconductor.org), and pathway analysis was conducted using Ingenuity Pathway Analysis (Ingenuity Systems, Qiagen, Valencia, CA). Statistical analysis indicated no interaction between risk and week. Therefore, the overall effect of risk was analyzed across all time points. In total, 3,500 genes were differentially expressed between the HR and LR cows (false discovery rate < 0.05). Of these, 2,897 genes were identified by Ingenuity Pathway Analysis and used for pathway analysis. Of the relevant pathways identified, neutrophils isolated from HR cows showed downregulation of genes involved in the recruitment of granulocytes, interferon signaling, and apoptosis, and upregulation of genes involved in cell survival. The results indicate that metabolically stressed cows had reduced neutrophil function during the peripartum period, highlighting a potential relationship between subclinical metabolic disease and innate immune function that suggests that metabolic health negatively affects the innate immune system and may contribute to the state of immunosuppression during the peripartum period. In this way, the metabolic stress among the HR cows may reduce their ability to combat infection during the transition period.

Immune status during postpartum, peri-implantation and early pregnancy in cattle: An updated view

Throughout the estrous cycle the mammalian endometrium undergoes morphological and functional changes that are essential for the establishment of pregnancy and proper ovarian and uterine functions. Among these changes, the most important are alterations in both inter- and intracellular signalling molecules, many of which modulate immune processes. In the endometrial tissue there are local innate (nonspecific) and adaptive (specific/acquired) response mechanisms which vary because of the endocrine status during the estrous cycle, pregnancy and postpartum period. Endometrial cells have responses that support the immune system by producing pro-inflammatory factors such as cytokines, sensors, effector molecules and chemokines. This response is important during gestation, pregnancy, and fetal growth, as well as in preventing infection, and immuno-rejection of the semi-allogeneic embryo. In dairy cows, both before and immediately after calving, there are marked changes in the values for hormonal and metabolic variables and the immune status is impaired. Thus, in several studies there has been assessment of the physiological and/or abnormal maternal immune changes and possible effects on dairy cow reproductive performance. The objective with this review is to summarize the novel information about the immune mechanisms involved during the postpartum period, subsequent peri-implantation period and pregnancy in dairy cows, and the possible effects on reproductive performance. This information provides for an enhanced understanding of the local and systemic immune responses associated with the metabolic and hormonal status of dairy cows, and alterations in the immune system of high producing cows and the possible effects on subsequent fertility.

Dietary supplementation of Scutellaria baicalensis extract during early lactation decreases milk somatic cells and increases whole lactation milk yield in dairy cattle

Systemic inflammation is common in early lactation dairy cows and is associated with decreased milk production. The Scutellaria baicalensis plant contains flavonoids with anti-inflammatory and anti-oxidative properties, which may counteract the inflammatory state in early lactation dairy cows. The objective of this experiment was to determine whether Scutellaria baicalensis extract (SBE), a source of bioactive flavonoids, would alter the adaptation to lactation. Multiparous Holstein cows (n = 122) were used in a randomized block design to determine the effect of short-term and long-term postpartum administration of SBE on 305-d milk yield, 120-d milk component yield, and early lactation milk markers of inflammation and metabolic function. Treatments were 1) control, 2) short term (5-d) administration of the SBE (SBE5), and 3) long term (60-d) administration of the SBE (SBE60). Treatments were included in a treatment pellet that was identical to a control pellet in ingredient source and composition except for the extract (10 g/d SBE providing 3.3 g/d of the flavonoid baicalin), both provided via an automated milking system beginning on d 1 of lactation. Milk samples were collected on d 1, 3, and once during d 5–12 of lactation, followed by weekly sampling until 120 days in milk (DIM). Milk samples collected in the first 2 wk were used for biomarker analysis (haptoglobin, β-hydroxybutyrate [BHB], and glucose-6-phosphate [G6P]), and all samples were used for composition analysis. Cows were body condition scored every 2 wk prepartum and postpartum. Milk production, programmed pellet allocation, and actual provision of both pelleted feeds were recorded daily. Treatment effects were evaluated by contrasts between control and SBE5 and control and SBE60 for both the treatment (TP; wk 1–9) and carryover periods (CP; wk 10–37). Total pellet offered was greater for SBE60 in both the TP (P < 0.01) and CP (P = 0.02) but was not different for SBE5 during either period (P ≥ 0.13). No treatment effects were observed for body condition score (BCS), milk haptoglobin, BHB, or G6P. SBE5 did not alter milk yield or milk components. SBE60 increased whole-lactation milk yield by 1,419 kg (13%; P = 0.03). SBE60 increased milk lactose and fat yields (P ≤ 0.04) and tended to increase milk protein yield (P = 0.09) during TP, and each increased during CP (P ≤ 0.04). Somatic cell count decreased by 10% in SBE60 during TP (P = 0.02) but not CP (P = 0.13). Mastitis incidence tended to differ by treatment, being lesser for both SBE5 and SBE60 vs. control (14 and 15% vs. 33%). SBE supplementation did not impact time to pregnancy or hazard of leaving the herd. In conclusion, despite no detected treatment effects on BCS or milk biomarkers of inflammation and metabolic status, supplementation of postpartum dairy cows with Scutellaria baicalensis extract for 60 d was effective at increasing whole lactation milk yield.

Redox Biology in Transition Periods of Dairy Cattle: Role in the Health of Periparturient and Neonatal Animals

Dairy cows undergo various transition periods throughout their productive life, which are associated with periods of increased metabolic and infectious disease susceptibility. Redox balance plays a key role in ensuring a satisfactory transition. Nevertheless, oxidative stress (OS), a consequence of redox imbalance, has been associated with an increased risk of disease in these animals. In the productive cycle of dairy cows, the periparturient and neonatal periods are times of increased OS and disease susceptibility. This article reviews the relationship of redox status and OS with diseases of cows and calves, and how supplementation with antioxidants can be used to prevent OS in these animals.

Metabolism and immune status during transition period influences the lactation performance in Zebu (Bos indicus) cows

We evaluated the changes in the concentration of innate immune molecules (haptoglobin: Hp, serum amyloid A: SAA, IL-6, TNF-α, IL-1β, and IL-8), energy indicators [NEFA, dry matter intake (DMI) and body condition scoring (BCS)] during the transition period in dual-purpose Zebu (Deoni breed) cows in relation to milk yield. Blood collection was done at weekly intervals (–21±2, –14±1, –7±1, d pre-partum, day 0 (date of calving) and 3±1, 7±1, 14±1, 21±2 d postpartum period) for estimation of above plasma variables using commercially available bovine specific ELISA kits. We also recorded DMI and BCS during the corresponding period. Transition cows were classified based on their milk yield during the study period as high (6), medium (6) and low (6) yielding cows and data were analyzed by using Mixed-model repeated measure analysis. High yielding (HY) cows had significantly higher concentrations of SAA, TNF-α, and IL-6 during pre-partum and early postpartum period than low yielding (LY) cows. DMI was significantly higher in HY cows than MY (3rd and 7th d) or LY cows (21st d) while, BCS was significantly higher in HY than LY cows during pre-partum period (-7th d). LY cows had significantly higher concentration of NEFA during the postpartum period (14th and 21st d). It is concluded that the active functioning of the immune system and more dry matter intake in transition Deoni cows enabled to synthesise more milk during the postpartum period.

Periparturient lipolysis and oxylipid biosynthesis in bovine adipose tissues

The periparturient period of dairy cows is characterized by intense lipolysis in adipose tissues (AT), which induces the release of free fatty acids (FFA) into circulation. Among FFA, polyunsaturated fatty acids are susceptible to oxidation and can modulate inflammatory responses during lipolysis within AT. Linoleic and arachidonic acid oxidized products (oxylipids) such as hydroxy-octadecadienoic acids (HODE) and hydroxy-eicosatetraenoic acids (HETE), were recently identified as products of lipolysis that could modulate AT inflammation during lipolysis. However, the effect of lipolysis intensity during the transition from gestation to lactation on fatty acid substrate availability and subsequent AT oxylipid biosynthesis is currently unknown. We hypothesized that in periparturient dairy cows, alterations in AT and plasma fatty acids and oxylipid profiles coincide with changes in lipolysis intensity and stage of lactation. Blood and subcutaneous AT samples were collected from periparturient cows at -27±7 (G1) and -10±5 (G2) d prepartum and at 8±3 d postpartum (PP). Targeted lipidomic analysis was performed on plasma and AT using HPLC-MS/MS. We report that FFA concentrations increased as parturition approached and were highest at PP. Cows exhibiting high lipolysis rate at PP (FFA>1.0 mEq/L) had higher body condition scores at G1 compared to cows with low lipolysis rate (FFA<1.0 mEq/L). Concentrations of plasma linoleic and arachidonic acids were increased at PP. In AT, 13-HODE, and 5-, 11- and 15-HETE were increased at PP compared to G1 and G2. Concentrations of beta hydroxybutyrate were positively correlated with those of 13-HODE and 15-HETE in AT. Plasma concentrations of 5- and 20-HETE were increased at PP. These data demonstrate that prepartum adiposity predisposes cows to intense lipolysis post-partum and may exacerbate AT inflammation because of increased production of pro-inflammatory oxylipids including 5- and 15-HETE and 13-HODE. These results support a role for certain linoleic and arachidonic acid-derived oxylipids as positive and negative modulators of AT inflammation during periparturient lipolysis.

Metabolic and Endocrine Role of Adipose Tissue During Lactation

The adipose tissue serves an essential role for survival and reproduction in mammals, especially females. It serves primarily as an energy storage organ and is directly linked to the reproductive success of mammals. In wild animals, adipose tissue function is linked to seasonality of the food supply to support fetal growth and milk production. Adipose tissue depots in ruminants and non-ruminants can secrete many signal molecules (adipokines) that act as hormones and as pro- and anti-inflammatory cytokines. The visceral adipose tissue especially appears to be more endocrinologically active than other adipose depots. The endocrine function is important for the overall long-term regulation of energy metabolism and plays an important role in the adaptation to lactation in many mammalian species, including humans. Furthermore, endocrine signals from adipose tissue depots contribute to fertility modulation, immune function, and inflammatory response. Energy homeostasis is modulated by changes in feed intake, insulin sensitivity, and energy expenditure, processes that can be influenced by adipokines in the brain and in peripheral tissues.

Expression of fatty acid sensing G-protein coupled receptors in peripartal Holstein cows

Background

G-protein coupled receptors (GPCR), also referred as Free Fatty Acid Receptors (FFAR), are widely studied within human medicine as drug targets for metabolic disorders. To combat metabolic disorders prevalent in dairy cows during the transition period, which co-occur with negative energy balance and changes to lipid and glucose metabolism, it may be helpful to identify locations and roles of FFAR and other members of the GPCR family in bovine tissues.

Results

Quantitative RT-PCR (qPCR) of subcutaneous adipose, liver, and PMNL samples during the transition period (-10, +7, and +20 or +30 d) were used for expression profiling of medium- (MCFA) and long-chain fatty acid (LCFA) receptors GPR120 and GPR40, MCFA receptor GPR84, and niacin receptor HCAR2/3. Adipose samples were obtained from cows with either high (HI; BCS ≥ 3.75) or low (LO; BCS ≤ 3.25) body condition score (BCS) to examine whether FFAR expression is correlated with this indicator of health and body reserves. Supplementation of rumen-protected methionine (MET), which may improve immune function and production postpartum, was also compared with unsupplemented control (CON) cows for liver and blood polymorphonuclear leukocytes (PMNL) samples. In adipose tissue, GPR84 and GPR120 were differentially expressed over time, while GPR40 was not expressed; in PMNL, GPR40 was differentially expressed over time and between MET vs. CON, GPR84 expression differed only between dietary groups, and GPR120 was not expressed; in liver, GPCR were either not expressed or barely detectable.

Conclusions

The data indicate that there is likely not a direct role in liver for the selected GPCR during the transition period, but they do play variable roles in adipose and PMN. In future, these receptors may prove useful targets and/or markers for peripartal metabolism and immunity.

Electronic supplementary material

The online version of this article (doi:10.1186/s40104-017-0150-z) contains supplementary material, which is available to authorized users.

Effects of rumen-protected Capsicum oleoresin on immune responses in dairy cows intravenously challenged with lipopolysaccharide

The objective of this experiment was to investigate the effects of rumen-protected Capsicum oleoresin (RPC) on productivity and immune responses including feed intake, milk yield and composition, white and red blood cells, lipid peroxidation, and blood concentration of cortisol, haptoglobin, glucose, and insulin in lactating dairy cows experimentally challenged with lipopolysaccharide (LPS). The experiment was a replicated 3 × 3 Latin square design with 9 multiparous Holstein cows in three 28-d periods. Treatments were 0 (control), 100, and 200 mg of RPC/cow per day, mixed with small portions of the total mixed ration and top-dressed. Bacterial LPS was intravenously administered at 1.0 μg/kg of body weight in the last week of each experimental period, and blood samples were collected at 0, 2, 4, 8, and 24 h after administration. Dry matter intake, milk yield, and white blood cells including neutrophils, lymphocytes, monocytes, and eosinophils were decreased, and rectal temperature, hemoglobin, and serum concentrations of cortisol and haptoglobin were increased by LPS. Red blood cells, platelets, and plasma concentration of thiobarbituric acid reactive substances were not affected by LPS. Dry matter intake, milk yield, and milk composition in the 5 d post-LPS challenge were not affected by RPC. Rectal temperature, white blood cells, red blood cells, hemoglobin, and platelets were also not affected by RPC. Compared with the control, RPC tended to decrease cortisol at 2 h following LPS challenge and decreased haptoglobin concentration in serum across sampling points. Concentration of thiobarbituric acid reactive substances in plasma was decreased by RPC at 24 h post-LPS challenge. Glucose and insulin were not affected by RPC, but serum insulin concentration at 8 h was lowered by RPC compared to the control. Collectively, RPC had no or subtle effects on feed intake, milk yield and composition, rectal temperature, white and red blood cells, and serum glucose and insulin concentration in dairy cows challenged by LPS. However, RPC tended to decrease cortisol and decreased concentrations of haptoglobin and thiobarbituric acid reactive substances in blood following LPS challenge. Data suggest that dietary supplementation of RPC may modulate acute phase responses induced by bacterial infection in lactating dairy cows.

Far-off and close-up dry matter intake modulate indicators of immunometabolic adaptations to lactation in subcutaneous adipose tissue of pasture-based transition dairy cows

The common practice of increasing dietary energy density during the close-up dry period (last ∼3 wk prepartum) has been recently associated with a higher incidence of metabolic disorders after calving. Despite these reports, over-feeding of metabolizable energy (ME) during the far-off, nonlactating period is a common management policy aimed at achieving optimum calving body condition score (BCS) in pasture-based systems, as cows are generally thinner than total mixed ration cows at the end of lactation. Our hypothesis was that both far-off and close-up overfeeding influence the peripartum adipose tissue changes associated with energy balance and inflammatory state. Sixty mid-lactation, grazing dairy cows of mixed age and breed were randomly allocated to 1 of 2 groups that were managed through late lactation to achieve a low and high BCS (approximately 4.25 and 5.0 on a 10-point scale) at dry-off. The low BCS cows were then overfed ME to ensure that they achieved the same BCS as the higher BCS group by calving. Within each rate of BCS gain treatment, cows were offered 65, 90, or 120% of their pre-calving ME requirements for 3 wk pre-calving in a 2 × 3 factorial arrangement of treatments (i.e., 10 cows/treatment). Subcutaneous adipose tissue was collected via biopsy at -1, 1, and 4 wk relative to parturition. Quantitative PCR was used to measure mRNA and microRNA expression of targets related to adipogenesis and inflammation. Cows overfed in the far-off period had increased expression of miR-143 and miR-378 prepartum (-1 wk) indicating greater adipogenesis, consistent with their rapid gain in BCS following dry-off. Furthermore, the lower postpartum expression of IL6, TNF, TLR4, TLR9, and miR-145, and a higher abundance of miR-99a indicated lower body fat mobilization in early lactation in the same group. In the close-up period, feeding either 65 or 120% of ME requirements caused changes in FASN, IL1B, IL6R, TLR9, and the microRNA miR-143, miR-155, and miR-378. Their respective expression patterns indicate a tentative negative-feedback mechanism in metabolically compromised, feed-restricted cows, and a possible immune-related stimulation of lipolysis in apparently static adipocytes in overfed cows. Data from cows fed 90% of ME requirements indicate the existence of a balance between lipolytic (inflammatory-related) and anti-lipolytic signals, to prime the mobilization machinery in light of imminent lactation. Overall, results indicate that far-off dry cow nutrition influences peripartum adipose tissue metabolism, with neither strategy negatively affecting the physiological adaptation to lactation. Furthermore, to ensure a favorable transition, cows should be subjected to a small feed restriction in the close-up period, irrespective of far-off nutritional management.

The association of plasma glucose, BHBA, and NEFA with postpartum uterine diseases, fertility, and milk production of Holstein dairy cows

The objective of this study was to investigate the association between the metabolic indicators such as nonesterified fatty acids (NEFA), β-hydroxybutyrate (BHBA), and glucose during the transition period and the development of uterine diseases. In total, 181 Holstein dairy cows were enrolled in the study. Plasma glucose, NEFA, and BHBA concentrations were measured at -50, -6, 3, 7, and 14 days relative to parturition. All cows enrolled in the study were evaluated for retained placenta (RP), metritis, and endometritis. Metritis and RP were diagnosed and treated by trained farm personnel. Clinical endometritis was evaluated by a veterinarian at 35 days in milk using a Metricheck device. We found plasma glucose concentration to be associated with the occurrence of metritis and clinical endometritis. Moreover, cows with an increased calving-to-conception interval (>150 days) presented higher plasma glucose concentrations than cows that became pregnant within the first 150 days, whereas BHBA and NEFA were not associated with the occurrence of any uterine disorder. Receiver operating characteristic (ROC) curves were used in an attempt to determine the cow-level critical thresholds for the occurrence of metritis, and endometritis. In addition, pairwise comparisons of area under the curve (AUC) of ROC curves for the critical thresholds for glucose, BHBA, and NEFA predicting the same uterine disease were performed. Glucose at 3 days in milk was the best predictor for metritis and endometritis diagnosis, with AUC values of 0.66 and 0.67, respectively. Multivariable logistic regressions were performed and showed that cows with higher levels of glucose at Day 3 were at 6.6 times higher odds of being diagnosed with metritis, and 3.5 times higher odds of developing clinical endometritis, compared with cows with lower glucose levels. Finally, a simple linear regression analysis demonstrated a negative correlation between daily milk yield in the first and second weeks of lactation and plasma glucose concentrations measured at Days 7 and 14, respectively. Concentrations of NEFA and BHBA were not found to be associated with milk production.

Effects of oral meloxicam administration to beef cattle receiving lipopolysaccharide administration or vaccination against respiratory pathogens

This study evaluated the effects of oral meloxicam administration on metabolic, inflammatory, and acute-phase responses of beef cattle receiving a lipopolysaccharide (LPS) challenge (Exp. 1; d -1 to 6) or vaccinated against respiratory pathogens (Exp. 2; d 7 to 21). Twenty-one Angus steers ( = 11) and heifers ( = 10) were housed in individual pens on d -15 and were offered free-choice water, mineral-vitamin mix, and hay until d 21. In Exp. 1, cattle were ranked on d -1 by sex and BW and assigned to 1) oral meloxicam administration (1 mg/kg BW daily) from day -1 to 6 (MEL8), 2) oral meloxicam administration (1 mg/kg BW) on d 0 and oral lactose monohydrate administration (1 mg/kg BW) on d -1 and from d 1 to 6 (MEL1), or 3) oral lactose monohydrate administration (1 mg/kg BW daily) from d -1 to 6 (CON). On d 0, cattle received an intravenous LPS bolus (0.5 μg/kg BW) concurrently with treatment administration. Rectal temperature (RTEMP) was assessed, and blood samples were collected at -2, 0, 2, 4, 6, 8, 12, 16, 24, 36, 48, 60, 72, 96, 120, and 144 h relative to LPS administration. No treatment effects were detected ( ≥ 0.36) for RTEMP, concentrations of serum tumor necrosis factor α (TNFα), plasma haptoglobin, cortisol, insulin, and leptin, as well as blood mRNA expression of α and cyclooxygenase-2, although all variables increased ( < 0.01) across treatments after LPS administration. In Exp. 2, cattle received the same treatments that they were assigned to in Exp. 1 from d 7 to d 13 and were vaccinated against respiratory pathogens concurrently with treatment administration on d 8. Blood samples were collected, and RTEMP was assessed as in Exp. 1 in addition to 168, 240, and 336 h relative to vaccination. No treatment effects were detected ( ≥ 0.26) for RTEMP, the same plasma and serum variables evaluated in Exp. 1, and serum concentrations of antibodies against or serum titers against bovine respiratory syncytial virus, bovine herpesvirus-1, bovine viral diarrhea virus-1, and parainfluenza-3 virus. All variables increased ( < 0.01) across treatments after vaccination, except for serum TNFα and titers against bovine viral diarrhea virus-1 ( ≥ 0.40). Collectively, this study found no evidence that oral meloxicam administration, at the doses and intervals utilized herein, mitigated the metabolic, inflammatory, and acute-phase reactions elicited by LPS administration or vaccination against respiratory pathogens.