Plasma proteomic profiling and pathway analysis of normal and overconditioned dairy cows during the transition from late pregnancy to early lactation

Unveiling the power of proteomics in advancing tropical animal health and production

Proteomics, the large-scale study of proteins in biological systems has emerged as a pivotal tool in the field of animal and veterinary sciences, mainly for investigating local and rustic breeds. Proteomics provides valuable insights into biological processes underlying animal growth, reproduction, health, and disease. In this review, we highlight the key proteomics technologies, methodologies, and their applications in domestic animals, particularly in the tropical context. We also discuss advances in proteomics research, including integration of multi-omics data, single-cell proteomics, and proteogenomics, all of which are promising for improving animal health, adaptation, welfare, and productivity. However, proteomics research in domestic animals faces challenges, such as sample preparation variation, data quality control, privacy and ethical considerations relating to animal welfare. We also provide recommendations for overcoming these challenges, emphasizing the importance of following best practices in sample preparation, data quality control, and ethical compliance. We therefore aim for this review to harness the full potential of proteomics in advancing our understanding of animal biology and ultimately improve animal health and productivity in local breeds of diverse animal species in a tropical context.

Metabolic Profiling in Ruminant Diagnostics

A herd-based approach and interpretative perspective is necessary in using metabolic profile testing in contrast to individual animal disease diagnostics. Metabolic profile testing requires formulating a question to be answered, followed by the appropriate selection of animals for testing. A range of blood analytes and nutrients can be determined with newer biomarkers being developed. Sample collection and handling and herd-based reference criteria adjusted to time relative to parturition are critical for interpretation. The objective of this article is to review the concepts and practical applications of metabolic profile testing in ruminants.

Invited review: Assessment of body condition score and body fat reserves in relation to insulin sensitivity and metabolic phenotyping in dairy cows

The purpose of this article is to review body condition scoring and the role of body fat reserves in relation to insulin sensitivity and metabolic phenotyping. This article summarizes body condition scoring assessment methods and the differences between subcutaneous and visceral fat depots in dairy cows. The mass of subcutaneous and visceral adipose tissue (AT) changes significantly during the transition period; however, metabolism and intensity of lipolysis differ between subcutaneous and visceral AT depots of dairy cows. The majority of studies on AT have focused on subcutaneous AT, and few have explored visceral AT using noninvasive methods. In this systematic review, we summarize the relationship between body fat reserves and insulin sensitivity and integrate omics research (e.g., metabolomics, proteomics, lipidomics) for metabolic phenotyping of cows, particularly overconditioned cows. Several studies have shown that AT insulin resistance develops during the prepartum period, especially in overconditioned cows. We discuss the role of AT lipolysis, fatty acid oxidation, mitochondrial function, acylcarnitines, and lipid insulin antagonists, including ceramide and glycerophospholipids, in cows with different body condition scoring. Nonoptimal body conditions (under- or overconditioned cows) exhibit marked abnormalities in metabolic and endocrine function. Overall, reducing the number of cows with nonoptimal body conditions in herds seems to be the most practical solution to improve profitability, and dairy farmers should adjust their management practices accordingly.

Clinical and diagnostic characteristics of the development of hepatocardial syndrome in black and white cows in the early lactation period

Background and Aim:

It is known that during the early postpartum and lactation periods in dairy cows, metabolic disorders develop, that is, ketosis, which can lead to secondary damage to internal organs. Therefore, it is important to address the issues of changing the lactating cows’ clinical, laboratory, and physiological parameters regarding the development of hepatocardial syndrome. This study aimed to provide clinical and diagnostic justification for developing hepatocardial syndrome in highly productive dairy cows.

Materials and Methods:

The study was conducted on 20 black and white cows in the early postpartum period (7–10 days after birth), with a milk production level of >4500 kg of milk during the previous lactation period, a positive result in the formol colloid sedimentary test, the presence of deafness and splitting of heart sounds, changes in the size, or increased pain sensitivity of the percussion field of the liver. Clinically healthy dairy cows in the early postpartum period were used as controls (n = 24). Clinical, electrocardiographic, echocardiographic, and biochemical parameters were also evaluated.

Results:

Dairy cows with hepatocardial syndrome developed arterial hypertension and sinus tachycardia, which led to a significant decrease in PQ and QT intervals at ECG. A significant increase in the diastolic size of the interventricular septum, systolic size of the free wall of the left ventricle, and diastolic and systolic sizes of the left ventricle and a significant decrease in the shortening fraction of the left ventricular myocardium were observed in the cows due to the development of hepatocardial syndrome. The affected cows demonstrated a significant increase in serum activity of gamma-glutamyl transferase, alanine aminotransferase, lactate dehydrogenase, creatine phosphokinase, alkaline phosphatase, troponin, malondialdehyde, diene conjugates, and ceruloplasmin and a decrease in glucose concentration. In addition, they demonstrated decreased activity of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase.

Conclusion:

Hepatocardial syndrome in dairy cows occurs due to ketosis, characterized by arterial hypertension, sinus tachycardia, a moderate decrease in myocardial contractility, oxidative stress, and cytolysis of cardiomyocytes and hepatocytes. Therefore, the control and prevention of the development of hepatocardial syndrome will make it possible to maintain the productive health and longevity of dairy cows.

Selection of early pregnancy specific proteins and development a rapid immunochromatographic test strip in cows

The most of embryo losses occur before the day 16 after artificial insemination, but there is no low cost and easy operation that can detect pregnancy with high accuracy within three weeks post-insemination in cattle. In this study, blood samples were collected at day 18 of the estrous cycle, and days 18, 25 and 35 of pregnancy, and relative levels of interferon stimulated genes (ISGs), Toll-like receptor (TLRs), complement components, early pregnancy factor (EPF) and pregnancy-associated plasma protein A (PAPPA) proteins were analyzed through Western blot. In addition, a colloidal gold immunochromatographic test strip was developed using the selected antibody, and the test was used for early pregnancy diagnosis. The results showed that there were changes in relative levels of plasma ISGs, TLRs, complement components, EPF and PAPPA proteins during early pregnancy in cattle, and complement component 1q (C1q) could be used as an ideal marker to develop a colloidal gold immunochromatographic test strip for early pregnancy diagnosis. In addition, the accuracy of pregnancy diagnosis by this test strip was 91.67% (11/12) for pregnant cows and 80% (8/10) nonpregnant cows at day 18 after insemination. In conclusion, the changes in plasma ISGs, TLRs, complement components, EPF and PAPPA proteins may be related to the maternal systemic immune modulation during early pregnancy, and a colloidal gold immunochromatographic test strip was developed for early pregnancy diagnosis using C1q as the ideal marker in cows. However, this colloidal gold immunochromatographic test strip needs further studies to improve the accuracy.

Plasma proteomics reveals crosstalk between lipid metabolism and immunity in dairy cows receiving essential fatty acids and conjugated linoleic acid

Essential fatty acids (EFA) and conjugated linoleic acids (CLA) are unsaturated fatty acids with immune-modulatory effects, yet their synergistic effect is poorly understood in dairy cows. This study aimed at identifying differentially abundant proteins (DAP) and their associated pathways in dairy cows supplied with a combination of EFA and CLA during the transition from antepartum (AP) to early postpartum (PP). Sixteen Holstein cows were abomasally infused with coconut oil as a control (CTRL) or a mixture of EFA (linseed + safflower oil) and CLA (Lutalin, BASF) (EFA + CLA) from − 63 to + 63 days relative to parturition. Label-free quantitative proteomics was performed on plasma samples collected at days − 21, + 1, + 28, and + 63. During the transition time, DAP, consisting of a cluster of apolipoproteins (APO), including APOE, APOH, and APOB, along with a cluster of immune-related proteins, were related to complement and coagulation cascades, inflammatory response, and cholesterol metabolism. In response to EFA + CLA, specific APO comprising APOC3, APOA1, APOA4, and APOC4 were increased in a time-dependent manner; they were linked to triglyceride-enriched lipoprotein metabolisms and immune function. Altogether, these results provide new insights into metabolic and immune adaptation and crosstalk between them in transition dairy cows divergent in EFA + CLA status.

Longitudinal liver proteome profiling in dairy cows during the transition from gestation to lactation: Investigating metabolic adaptations and their interactions with fatty acids supplementation via repeated measurements ANOVA-simultaneous component analysis

Repeated measurements analysis of variance - simultaneous component analysis (ASCA) has been developed to handle complex longitudinal omics datasets and combine novel information with existing data. Herein, we aimed at applying ASCA to 64 liver proteomes collected at 4-time points (day -21, +1, +28, and + 63 relative to parturition) from 16 Holstein cows treated from 9 wk. antepartum to 9 wk. postpartum (PP) with coconut oil (CTRL) or a mixture of essential fatty acids (EFA) and conjugated linoleic acid (CLA) (EFA + CLA). The ASCA modeled 116, 43, and 97 differentially abundant proteins (DAP) during the transition to lactation, between CTRL and EFA + CLA, and their interaction, respectively. Time-dependent DAP were annotated to pathways related to the metabolism of carbohydrates, FA, and amino acid in the PP period. The DAP between FA and the interaction effect were annotated to the metabolism of xenobiotics by cytochrome P450, drug metabolism - cytochrome P450, retinol metabolism, and steroid hormone biosynthesis. Collectively, ASCA provided novel information on molecular markers of metabolic adaptations and their interactions with EFA + CLA supplementation. Bioinformatics analysis suggested that supplemental EFA + CLA amplified hepatic FA oxidation; cytochrome P450 was enriched to maintain metabolic homeostasis by oxidation/detoxification of endogenous compounds and xenobiotics. SIGNIFICANCE: This report is among the first ones applying repeated measurement analysis of variance-simultaneous component analysis (ASCA) to deal with longitudinal proteomics results. ASCA separately identified differentially abundant proteins (DAP) in 'transition time', 'between fatty acid treatments', and 'their interaction'. We first identified the molecular signature of hepatic metabolic adaptations during postpartum negative energy balance; the enriched pathways were well-known pathways related to mobilizing fatty acids (FA) and amino acids to support continuous energy production through fatty acid oxidation, TCA cycle, and gluconeogenesis. Some of the DAP were not previously reported in transition dairy cows. Secondly, we provide novel information on the mechanisms by which supplemented essential FA and conjugated linoleic acids interact with hepatic metabolism. In this regard, FA amplified hepatic detoxifying and oxidation capacity through ligand activation of nuclear receptors. Finally, we briefly compared the strengths and weaknesses of the ASCA model with PLS-DA and outlined why these methods are complementary.

Blood and adipose tissue steroid metabolomics and mRNA expression of steroidogenic enzymes in periparturient dairy cows differing in body condition

In high-yielding dairy cows, the rapidly increasing milk production after parturition can result in a negative nutrient balance, since feed intake is insufficient to cover the needs for lactation. Mobilizing body reserves, mainly adipose tissue (AT), might affect steroid metabolism. We hypothesized, that cows differing in the extent of periparturient lipomobilization, will have divergent steroid profiles measured in serum and subcutaneous (sc)AT by a targeted metabolomics approach and steroidogenic enzyme profiles in scAT and liver. Fifteen weeks antepartum, 38 multiparous Holstein cows were allocated to a high (HBCS) or normal body condition (NBCS) group fed differently until week 7 antepartum to either increase (HBCS BCS: 3.8 ± 0.1 and BFT: 2.0 ± 0.1 cm; mean ± SEM) or maintain BCS (NBCS BCS: 3.0 ± 0.1 and BFT: 0.9 ± 0.1 cm). Blood samples, liver, and scAT biopsies were collected at week -7, 1, 3, and 12 relative to parturition. Greater serum concentrations of progesterone, androsterone, and aldosterone in HBCS compared to NBCS cows after parturition, might be attributed to the increased mobilization of AT. Greater glucocorticoid concentrations in scAT after parturition in NBCS cows might either influence local lipogenesis by differentiation of preadipocytes into mature adipocytes and/or inflammatory response.

Host Serum Proteins as Potential Biomarkers of Bovine Tuberculosis Resistance Phenotype

Eradication of bovine tuberculosis (bTB) continues to be a worldwide challenge. The lack of reliable vaccines dampens the control and eradication programs of Mycobacterium bovis infection and spread. Selection and breeding of cattle resistant to M. bovis infection would greatly enhance the effectiveness of bTB eradication programs. Here, we have evaluated the potential of serum proteins as biomarkers of cattle resistance to bTB in Holstein-Friesian cows, 6-8-year-old, born and raised in similar conditions in herds with bTB prevalence >30%. Serum proteins obtained from uninfected cows (bTB-resistant; R) were compared to those from infected cows (bTB-susceptible; S), defined by a negative or positive bTB diagnosis, respectively. bTB diagnosis included: (i) single intradermal (caudal fold) tuberculin test, (ii) whole blood IFN-gamma test, (iii) gross visible lesions in lymph nodes and lungs by inspection at the abattoir, and (iv) a bacteriological culture for M. bovis. Using 2D-GE and LC-ESI-MS/MS, we found higher expression levels of primary amine oxidase (AO), complement component 5 (C5), and serotransferrin (TF) in R cattle than S cattle. In-house developed and standardized ELISAs for these novel biomarkers showed the best sensitivities of 72, 77, 77%, and specificities of 94, 94, 83%, for AO, C5, and TF, respectively. AUC-ROC (95% CI) values of 0.8935 (0.7906-0.9964), 0.9290 (0.8484-1.010), and 0.8580 (0.7291-0.9869) were obtained at cut-off points of 192.0, 176.5 ng/ml, and 2.1 mg/ml for AO, C5, and TF, respectively. These proteins are involved in inflammatory/immunomodulatory responses to infections and may provide a novel avenue of research to determine the mechanisms of protection against bTB. Overall, our results indicate that these proteins could be novel biomarkers to help identify cattle resistant to bTB, which in turn could be used to strengthen the effectiveness of existing eradication programs against bTB.

Longitudinal changes in fatty acid metabolism and in the mitochondrial protein import system in overconditioned and normal conditioned cows: A transcriptional study using microfluidic quantitative PCR

This study investigated the effect of body condition around calving on the hepatic mRNA expression of genes involved in fatty acid (FA) metabolism and mitochondrial protein import system of dairy cows during the transition period. Fifteen weeks before their anticipated calving date, 38 multiparous Holstein cows were selected based on their current and previous body condition scores (BCS) and allocated to either a high or a normal BCS group (19 cows each). They received different diets to reach targeted differences in BCS and backfat thickness (BFT) until dry-off. At dry-off, normal BCS (NBCS) cows had a BCS <3.5 and BFT <1.2 cm, and the high BCS (HBCS) cows had a BCS >3.75 and BFT >1.4 cm. The expression of targeted genes in the liver was assayed by reverse-transcription quantitative real-time PCR using microfluidics integrated fluidic circuit chips on a subset of 5 cows from each group. Liver biopsies were collected at d -49, +3, +21, and +84 relative to parturition. The mRNA abundance of 47 genes related to lipid metabolism including carnitine metabolism, FA uptake and transport, lipoprotein export, carnitine metabolism, mitochondrial and proximal FA oxidation, ketogenesis, AMP-activated protein kinase/mammalian target of rapamycin pathway, and mitochondrial protein import system was assessed in liver tissue. The mRNA abundances of FA binding protein (FABP)6 (in both groups), and FABP1 and solute carrier family 22 member 5 (SLC22A5) in HBCS were upregulated (>1.5-fold change, FC) in early lactation (at d +3 and +21 postpartum) compared with antepartum (d -49), indicating promoted FA uptake and intracellular transport in the liver due to the metabolic adaptations of elevated lipo-mobilization after parturition. The upregulation of SLC22A5 and SLC25A20 after parturition was more pronounced in HBCS than in NBCS cows, suggesting a need for increasing the capacity of FA uptake, and FA transport into the hepatocyte. The increased mRNA abundance of carnitine palmitoyltransferase 1A, after parturition and to a greater extent in HBCS (FC = 4.1) versus NBCS (FC = 2.1) indicates a physiological increase in the capacity of long-chain fatty acyl-CoA entry into the liver mitochondria compared with antepartum (ap; d -49 relative to calving). The greater hepatic mRNA abundance of genes encoding enzymes involved in mitochondrial FA oxidation in HBCS than in NBCS points to an increased rate of mitochondrial β-oxidation. The hepatic mRNA abundance of 3-hydroxy-3-methylglutaryl-CoA synthase 2 and 3-hydroxy-3-methylglutaryl-CoA were upregulated after parturition (d +21/d +3 pp) to a greater extent in HBCS than in NBCS cows, indicating that excess acetyl-CoA generated via β-oxidation was increasingly used for ketogenesis. We observed for the first time that the mRNA abundance of genes involved in the translocase of the inner membrane (TIM) complex (TIM22 and TIM23) in the hepatic mitochondrial protein import system were undergoing distinct changes during the transition from late pregnancy to early lactation in dairy cows. Even though sample size in this study was relatively small, the results support that overconditioning around calving may contribute to mitochondrial FA overload and greater ketogenesis at the level of transcription in the liver of early lactation cows.

Domestic animal proteomics in the 21st century: A global retrospective and viewpoint analysis

Animal production and health are of significant economic importance, particularly regarding the world food supply. Animal and veterinary sciences have evolved immensely in the past six decades, particularly in genetics, nutrition, housing, management and health. To address major challenges such as those posed by climate change or metabolic disorders, it is of utmost importance to use state-of-the-art research tools. Proteomics and the other post-genomic tools (transcriptomics or metabolomics) are among them. Proteomics has experienced a considerable development over the last decades. This brought developments to different scientific fields. The use and adoption of proteomics tools in animal and veterinary sciences has some limitations (database availability or access to proteomics platforms and funding). As a result, proteomics' use by animal science researchers varies across the globe. In this viewpoint article, we focus on the developments of domestic animal proteomics over the last decade in different regions of the globe and how the researchers have coped with such challenges. In the second part of the article, we provide examples of funding, educational and laboratory establishment initiatives designed to foster the development of (animal-based) proteomics. International scientific collaboration is a definitive and key feature in the development and advancement of domestic animal proteomics. SIGNIFICANCE: Animal production and health are very important for food supply worldwide particularly as a source of proteinaceous foods. Animal and veterinary sciences have evolved immensely in the last decades. In order to address the major contemporary challenges facing animal and veterinary sciences, it is of utmost importance to use state-of-the-art research tools such as Proteomics and other Omics. Herein, we focus on the major developments in domestic animal proteomics worldwide during the last decade and how different regions of the world have used the technology in this specific research field. We address also major international efforts aiming to increase the research output in this area and highlight the importance of international cooperation to address specific problems inherent to domestic animal proteomics.

Uterine, vaginal and placental blood flows increase with dynamic changes in serum metabolic parameters and oxidative stress across gestation in buffaloes

The aims of the present study were to determine uterine, vaginal and placental blood flows by Doppler ultrasound cross-buffalo gestation and to evaluate the relationships among reproductive Doppler parameters and serum metabolic parameters as well as oxidative stress. Uterine (UA) and vaginal (VA) arteries were scanned every month, and placentome was scanned from month 4 till 8 in gestation. Time-averaged maximum velocity (TAMV), pulsatility index (PI), resistance index (RI), systolic/diastolic ratio (SD) and arterial diameter (AD) were used for accessing UA and VA hemodynamics. Time-averaged maximum velocity positively correlated with and AD, and both negatively correlated with their PI, RI and SD in UA and VA. TAMV and AD increased constantly in pregnancy, with maximum increase in months 4 and 9. Pulsatility index, RI and AD of UA decreased between months 4 and 9, while PI, RI and AD of VA decreased between months 5 and 9 and then increased in month 10 in pregnancy. Time-averaged maximum velocity of placentome blood flow increased exponentially from months 4 to 8, but decreased at the last two months in pregnancy. Serum lipids were significantly higher in the first month compared to all other months, while glucose was significantly lower in months 9 and 10. Malondialdehyde increased from month 3 till term, but peaked in month 5 and 10. Glutathione and catalase were highest in the first month and remained after. Time-averaged maximum velocity and AD for both UA and VA negatively correlated with serum lipids, glucose, catalase and glutathione, while positively correlated with malondialdehyde and total protein. Thus, increases in uterine blood flow (UtBF), vaginal blood flow (VaBF) and placental blood flow (PaBF) are associated with increased metabolism and oxidative stress in buffalo pregnancy.

Profiling of circulating microRNA and pathway analysis in normal- versus over-conditioned dairy cows during the dry period and early lactation

The objective of this study was to determine the circulating microRNA (miRNA) profile in over-conditioned (HBCS) versus normal-conditioned (NBCS) dairy cows in combination with pathway enrichment analyses during the transition period. Thirty-eight multiparous Holstein cows were selected 15 wk before anticipated calving date based on their current and previous body condition scores (BCS) for forming either a HBCS group (n = 19) or a NBCS group (n = 19). They were fed different diets during late lactation to reach the targeted differences in BCS and backfat thickness until dry-off. A subset of 15 animals per group was selected based on their circulating concentrations of nonesterified fatty acids (on d 14 postpartum) and β-hydroxybutyrate (on d 21 postpartum), representing the greater or the lower extreme values within their BCS group. Blood serum obtained at d -49 and 21 relative to parturition (3 pools with 5 cows per each group and time point) were used to identify miRNA that were differentially expressed (DE) between groups or time points using miRNA sequencing. No DE-miRNA were discovered between NBCS versus HBCS. Comparing pooled samples from d -49 and d 21 resulted in 7 DE-miRNA in the NBCS group, of which 5 miRNA were downregulated and 2 miRNA were overexpressed on d 21 versus -49. The abundance of 5 of these DE-miRNA was validated in all individual samples via quantitative PCR and extended to additional time points (d -7, 3, 84). Group differences were observed for miR-148a, miR-122 as well as miR-455-5p, and most DE-miRNA (miR-148a, miR-122, miR-30a, miR-450b, miR-455-5p) were downregulated directly after calving. Subsequently, the DE-miRNA was used for bioinformatics analysis to identify putative target genes and the most enriched biological pathways. The most significantly enriched pathways of DE-miRNA were associated with cell cycle and insulin signaling as well as glucose and lipid metabolism. Overall, we found little differences in circulating miRNA in HBCS versus NBCS cows around calving.