Intramammary administration of lipopolysaccharides at parturition enhances immunoglobulin concentration in goat colostrum

In newborn ruminants, transfer of passive immunity is essential to obtain protection against pathogens. This study aimed to increase the permeability of the blood-milk barrier using intramammary lipopolysaccharides (LPS) in goats at parturition to modulate colostrum composition. Twenty multiparous Majorera dairy goats were randomly allocated in one of the two experimental groups. The LPS group (n = 10) received an intramammary administration (IA) of saline (2 mL) containing 50 µg of LPS from Escherichia coli (O55:B5) in each half udder at parturition. The control group (n = 10) received an IA of saline (2 mL). Rectal temperature (RT) was recorded, and a blood sample was collected at parturition (before IA). In addition, RT was measured, and blood and colostrum/milk samples were collected on day (d) 0.125 (3 hours), 0.5 (12 hours), 1, 2, 4, 7, 15 and 30 relative to the IA. Goat plasma immunoglobulin G (IgG) and M (IgM) and serum β-hydroxybutyrate, glucose, calcium, free fatty acids, lactate dehydrogenase and total protein concentrations were determined. Colostrum and milk yields as well as chemical composition, somatic cell count (SCC), IgG and IgM concentrations were measured. The MIXED procedure (SAS 9.4) was used, and the model included the IA, time, and the interaction between both fixed effects. Statistical significance was set as P < 0.05. Goats from the LPS group showed higher RT on d 0.125, 0.5 and 4 relative to the IA compared to the control group (PIA×Time = 0.007). Goat serum biochemical variables and plasma IgG and IgM concentrations were not affected by the IA. Colostrum and milk yield as well as chemical composition were not affected by the IA, except for milk lactose percentage that was lower in the LPS group compared to the control group (4.3 ± 0.08 and 4.6 ± 0.08%, respectively PIA = 0.026). Colostrum SCC was higher in the LPS group than in the control group (3.5 ± 0.09 and 3.1 ± 0.09 cells × 106/mL, respectively; PIA = 0.011). Similarly, milk SCC increased in the LPS group compared to the control group (PIA = 0.004). The LPS group showed higher IgG (PIA = 0.044) and IgM (PIA = 0.037) concentrations on colostrum than the control group (31.9 ± 4.8 and 19.0 ± 4.8 mg/mL, 0.8 ± 0.08 and 0.5 ± 0.08 mg/mL, respectively). No differences in milk IgG and IgM concentrations between groups were observed. In conclusion, the IA of LPS at parturition increases RT, SCC and IgG and IgM concentrations in colostrum without affecting either yield or chemical composition.

Goat mammary gland metabolism: An integrated Omics analysis to unravel seasonal weight loss tolerance

Seasonal weight loss (SWL), is a major limitation to animal production. In the Canary Islands, there are two dairy goat breeds with different levels of tolerance to SWL: Majorera (tolerant) and Palmera (susceptible). Our team has studied the response of these breeds to SWL using different Omics tools. The objective of this study was to integrate such results in a data driven approach and using dedicated tools, namely the DIABLO method. The outputs of our analysis mainly separate unrestricted from restricted goats. Metabolites behave as "hub" molecules, grouping interactions with several genes and proteins. Unrestricted goats upregulated protein synthesis, along with arginine catabolism and adipogenesis pathways, which are related with higher anabolic rates and a larger proportion of secretory tissue, in agreement with their higher milk production. Contrarily, restricted goats seemingly increased the synthesis of acetyl-CoA through serine and acetate conversion into pyruvate. This may have occurred to increase fatty acid synthesis and/or to use them as an energy source in detriment to glucose, which was more available in the diet of unrestricted goats. Lastly, restricted Palmera upregulated the expression of PEBP4 and GPD1 genes compared to all other groups, which might support their use as putative biomarkers for SWL susceptibility. SIGNIFICANCE: Seasonal weight loss (SWL) is a major issue influencing animal production in the tropics and Mediterranean. By studying its impact on the mammary gland of tolerant and susceptible dairy goat breeds, using Omics, we aim at surveying the tissue for possible biomarkers that reflect these traits. In this study, data integration of three Omics (transcriptomics, proteomics and metabolomics) was performed using bioinformatic tools, to relate putative biomarkers and evaluate all three levels of information; in a novel approach. This information can enhance selection programs, lowering the impact of SWL on food production systems.

Effects of feeding level, milking frequency, and single injection of cabergoline on blood metabolites, hormones, and minerals around dry-off in dairy cows

This study aimed to investigate the effect of the different dry-off strategies based on reducing feeding level (normal vs. reduced energy density), reducing milking frequency (twice vs. once daily), and administration of a dopamine agonist after last milking (i.e. saline vs. cabergoline injection) on blood metabolites, hormones, and minerals around dry-off. In this experiment, 119 Holstein dairy cows were used in a 2 × 2 × 2 factorial arrangement. In the last week before dry-off, cows were allocated to 1 of the 4 possible dry-off strategies based on feeding level and milking frequency. Within 3 h after last milking, cows were injected with either saline or a D₂ dopamine agonist (cabergoline; Velactis, Ceva Santé Animale, Libourne, France; labeled for use only with abrupt dry-off, e.g., no preceding reduction in feeding level or milking frequency before last milking). After dry-off, all cows were fed the same dry cow diet and data collection continued for a week. Blood samples were collected from the coccygeal vein on d -9, -6, -5, -2, 1, 2, 5, and 7 relative to dry-off. Additionally, blood was sampled at 0, 3, and 6 h relative to injection of either cabergoline or saline, equivalent to d 0.125, 0.250, and 0.375 relative to last milking (dry-off). The reduced feeding level before dry-off caused reduced glucose and insulin concentrations as well as increased free fatty acid concentrations, particularly when reduced feeding level was combined with milking the cows 2× daily. The intramuscular injection of cabergoline caused the expected reduction in circulating prolactin concentrations. In addition, dopamine-agonist cabergoline induced an atypical simultaneous pattern of plasma metabolites (i.e., increased glucose and free fatty acid concentrations), hormones (i.e., reduced insulin and increased cortisol concentrations), and minerals (i.e., reduced calcium concentration), indicating that normal metabolic and mineral homeostatic regulations were hindered after the injection of ergot alkaloid cabergoline. In conclusion, reducing milking frequency seems the best management strategy to reduce milk production at dry-off among those tested in this study.

Feed restriction around parturition does not affect colostrum immunoglobulin G concentration in dairy fat-tailed sheep but does affect performance and blood metabolites in newborn lambs

This study aimed to investigate the effect of prepartum and postpartum feed restriction of fat-tailed dairy sheep on colostrum IgG concentration, and performance and blood metabolites of newborn fat-tailed lambs. Twenty fat-tailed dairy sheep were randomly allocated into control (Ctrl; n = 10) and feed restriction (FR; n = 10) groups. The Ctrl group received a diet that met 100% of energy requirements, both prepartum (from wk -5 to parturition) and postpartum (from parturition to wk 5). The FR group received a diet equivalent to 100, 50, 65, 80, and 100% of the energy requirements in wk -5, -4, -3, -2, and -1 relative to parturition, respectively. After parturition, the FR group received a diet equivalent to the 100, 50, 65, 80, and 100% of the energy requirements in wk 1, 2, 3, 4, and 5, respectively. At birth, lambs were assigned to their dam's experimental group. Both the Ctrl lambs (n = 10) and the FR lambs (n = 10) were allowed to suck colostrum and milk from the dams. Colostrum samples (50 mL) were collected at parturition (0 h) and then at 1, 12, 24, 36, 48, and 72 h postpartum. Blood samples were collected from all lambs before suckling colostrum (0 h) and then at 1, 12, 24, 36, 48, and 72 h after birth and weekly until the end of the experimental period (i.e., wk 5 relative to birth). The data were evaluated using the MIXED procedure of SAS (SAS Institute Inc.). The model included feed restriction, time, and the interaction feed restriction × time as fixed effects. The individual lamb was set as a repeated subject. Variables measured in colostrum and plasma were considered dependent variables, and significance was set at P < 0.05. Prepartum and postpartum feed restriction in fat-tailed dairy sheep did not affect colostrum IgG concentration. Consequently, no differences in blood IgG concentrations were observed in the lambs. In addition, the prepartum and postpartum feed restriction experienced by fat-tailed dairy sheep caused decreased body weight and milk intake in lambs from the FR group compared with the Ctrl group. Feed restriction also promoted increased concentration of blood metabolites such as triglycerides and urea in FR lambs compared with control lambs. In conclusion, prepartum and postpartum feed restriction in fat-tailed dairy sheep did not affect either colostrum IgG concentration or blood IgG concentration of the lambs. However, prepartum and postpartum feed restriction decreased lamb milk intake and, therefore, lamb body weight gain during the first 5 wk after birth.

Feeding milk supplemented with Ulva sp., Ascophyllum nodosum, or Saccharina latissima to preweaning dairy calves: Effects on growth, gut microbiota, gut histomorphology, and short-chain fatty acids in digesta

Emerging knowledge shows the importance of preweaning nutrition on programming the gastrointestinal microbiome and development of the gut barrier function. The aim of this study was to assess the effects of supplementing cow milk with either intact dried Ulva sp., Ascophyllum nodosum, or Saccharina latissima on growth performance and several gut health parameters of preweaning dairy calves. Forty male Holstein calves were selected based on birth weight (41 ± 4 kg) and plasma Brix percentage (≥8.7%) at d 2 of life. From d 2 to d 42 of life, the control calves (n = 10) were fed with cow milk (8 L/d) without seaweed supplementation, and the experimental calves were fed with cow milk (8 L/d) supplemented with either Ulva sp. (n = 10), A. nodosum (n = 10), or S. latissima (n = 10) at a concentration of 50 g/8 L of cow milk per day (i.e., 5% on a dry matter basis). Calves were weighed every week, and body weight gain and calf starter intake were monitored weekly. At d 42 ± 3 of life, calves were slaughtered. The organ weights and digesta pH from the reticulorumen, mid- and end small intestine, and mid-colon were recorded. A tissue sample (5 cm) collected from the mid-small intestine was analyzed for histomorphology. Digesta from the mid-small intestine and mid-colon were analyzed for lactobacilli, Escherichia coli, and Enterobacteriaceae, and short-chain fatty acid profile. Weight gain of the calves was not affected by seaweed supplementation. Proportional organ weights were not affected by seaweed supplementation except for reticulorumen weight, which was higher in calves fed Ulva sp. Both the mid-small intestinal and mid-colonic digesta populations of lactobacilli, Enterobacteriaceae, and E. coli, as well as the mid-small intestinal histomorphology in seaweed-supplemented calves were not different from control calves. However, acetic acid proportion in mid-colonic digesta was increased in calves fed Ulva sp. and A. nodosum, whereas butyric acid proportion was decreased compared with the control calves. Digesta pH in mid- and end small intestine and mid-colon were not affected, whereas ruminal pH was increased in calves fed Ulva sp. compared with the control calves. In conclusion, intact dried seaweed supplementation did not improve the growth or selected gut health parameters (i.e., histomorphology, digesta pH, bacteria, and short-chain fatty acids) in preweaning Holstein calves.

Effects of feeding level, milking frequency, and single injection of cabergoline on feed intake, milk yield, milk leakage, and clinical udder characteristics during dry-off in dairy cows

Abrupt and gradual dry-off strategies by reducing feeding level (normal vs. reduced energy density), reducing milking frequency (twice vs. once daily), and administration of a dopamine agonist after last milking (i.m. saline vs. cabergoline injection) were investigated (2 × 2 × 2 factorial arrangement) for their effects on feed intake, milk yield, energy balance, milk leakage, and clinical udder characteristics in 119 Holstein cows. In the last week before dry-off, cows were assigned to 1 of 4 combinations of feeding level and milking frequency. Within 3 h after last milking, cows were injected with either saline or a dopamine agonist (cabergoline; Velactis, Ceva Santé Animale; labeled for use only with abrupt dry-off, i.e., no preceding reduction in feeding level or milking frequency before last milking). After dry-off, all cows were fed the same diet for dry cows, and data collection continued for a week. Dry matter intake (DMI) was recorded in automated feed bins and milk yield in an automatic milking system where additional concentrate was fed. Clinical udder characteristics and milk leakage were scored 10 times during the week before and the week after dry-off. Before dry-off, total DMI decreased with reduced feeding level compared with normal feeding level, but did not differ between milking frequencies. The combined effect of reduced DMI and diet energy concentration resulted in a 47% lower net energy intake with reduced feeding level compared with normal feeding level during the week before dry-off. Milk yield was approximately 30% lower during the week before dry-off when either feeding level or milking frequency was reduced compared with no change in feeding level or milking frequency, whereas milk yield was 45% lower when both feeding level and milking frequency were reduced. The net energy balance during the week before dry-off was negative with reduced feeding level and more negative when combined with twice-daily milking. After dry-off, udder engorgement was reduced in the 3 gradual dry-off treatments compared with abrupt dry-off. Cabergoline injection after last milking resulted in least udder engorgement and signs of milk leakage for 48 h, but also resulted in abrupt reduction of DMI lasting approximately 24 h irrespective of treatment before dry-off. In conclusion, gradual cessation of lactation by reducing milking frequency to once daily without reducing the feeding level decreased milk yield before dry-off in high-yielding dairy cows and reduced udder engorgement after dry-off without inducing negative energy balance during the period of dry-off. In contrast, reduced feeding level induced negative energy balance, which may compromise welfare due to metabolic stress and hunger. No clear differences in risk of milk leakage after dry-off were observed between abrupt and gradual dry-off management strategies. Use of cabergoline led to fewer signs of milk leakage and reduced udder engorgement during the first days after dry-off, which may positively affect welfare at dry-off. However, the mechanism behind and the welfare consequences of the concomitant abrupt decrease in DMI lasting approximately 24 h needs further investigation to complete our understanding of dopamine agonist use for dry-off.

Daily alternation of the dietary starch level in Holstein dairy cows

The aim of this study was to investigate the effect of controlled daily alternations in dietary starch level on changes in rumen environment, blood, urine, and milk metabolites of dairy cows. Six multiparous mid-lactation Holstein cows were used in a replicated 3 × 3 Latin square design with 14-d periods and 3 alternating levels of dietary starch as treatments. Each 14-d period consisted of a 7-d baseline period and 7-d alternating period where diets alternated day to day. During the baseline period, all cows were fed a control diet containing 21% starch (dry matter basis). During the alternating period, the control diet was replaced with 1 of the 3 experimental diets on d 8, 10, 12, and 14. The 3 experimental diets contained 28% (low), 35% (medium), and 42% (high) starch (dry matter basis). At d 7 (baseline), 8 (ALT1), and 14 (ALT4) of each period, rumen fluid, blood, urine, and quarter milk (i.e., back right quarter) samples were collected at -0.5, 1, 2.5, 4, 5.5, and 7 h relative to morning feeding (0800 h). No differences were observed in dry matter intake, milk yield, and milk chemical composition. Rumen medial pH was lower in the high alternation level compared with the low or medium alternation levels at ALT1 but did not differ among starch alternation levels at ALT4. Similarly, the difference between rumen pH in medial and ventral contents was reduced at ALT1 with high alternation level but was not affected at ALT4. Total volatile fatty acid (VFA) concentrations were higher in the rumen medial fluid of the high alternation level at 7 h relative to morning feeding compared with those from the low and medium alternation levels. Similarly, total VFA concentrations constantly increased and were the highest in the ventral rumen fluid at 7 h relative to morning feeding, although no differences were detected among starch alternation levels. In both rumen medial and ventral fluids, the high alternation level showed higher propionate and lower acetate proportions compared with low and medium alternation levels. No differences in blood pH were detected among starch alternation levels. However, glucose concentrations tended to be higher in cows from the high alternation level. l-Lactate concentrations in blood were higher in ALT1 than in ALT4 but were not affected by the starch alternation level. In urine, no differences in pH or l-lactate concentrations were detected among alternation levels (i.e., low, medium, and high). Similarly, no differences in milk pH were detected among alternation levels. According to these results, it seems that the daily dietary starch alternation from 21% up to 42% (dry matter basis) is able to affect the ruminal fluid, especially during the first alternation. However, these changes in rumen fluid did not cause any effect on the variables measured in blood, urine, or milk. This study indicates that cows can cope with day-to-day alternations in type of rumen fermentable organic matter; however, longer-term effects on performance and health should be addressed in future studies.

Prepartum and Postpartum Feed Restrictions Affect Blood Metabolites and Hormones Reducing Colostrum and Milk Yields in Fat-Tailed Dairy Sheep

Simple Summary

Despite the fact that fat-tailed sheep raised for meat production are well known for being resilient to harsh environmental conditions such as pasture scarcity or low-quality feedstuffs, no studies regarding feed restriction have been performed on fat-tailed dairy sheep. In this study, prepartum feed restriction from week −5 to week −1 relative to parturition did not affect body weight. Similarly, postpartum feed restriction from week 1 to week 5 relative to parturition did not affect body weight. However, both prepartum and postpartum feed restrictions affected blood metabolites and hormones, which decreased both colostrum and milk yields postpartum.

Abstract

This study aimed to investigate the effect of prepartum and postpartum feed restriction on body weight (BW), blood metabolites, and hormones as well as colostrum and milk yields and compositions in fat-tailed dairy sheep. In this study, 20 multiparous and pregnant ewes were randomly allocated to either the control (Ctrl; n = 10) or the feed-restricted (FR; n = 10) groups from week −5 to week 5 relative to parturition. Despite dry matter intake being decreased in the FR group compared to the Ctrl throughout both prepartum and postpartum periods, no differences in BW were detected between groups in any of the studied periods. Feed restriction increased both free fatty acids and beta-hydroxybutyrate concentrations during both prepartum and postpartum periods. Similarly, feed restriction increased triglyceride concentration postpartum. Additionally, feed restriction increased insulin and growth hormone and decreased prolactin concentrations during both prepartum and postpartum periods. Feed restriction caused a decreased colostrum yield and a relative increase of the main colostrum components in the FR group. Similarly, milk yield decreased in the FR group compared to the Ctrl group, although milk components were not affected. In conclusion, feed restriction did not affect BW but decreased colostrum and milk yield in fat-tailed dairy sheep.

Chemical and fatty acid composition of Manchego type and Panela cheeses manufactured from either hair sheep milk or cow milk

This study compared the chemical composition and fatty acid (FA) profile of Manchego type cheese and Panela cheese made from hair sheep milk and compared these with both types of cheese manufactured with cow milk as a reference. In addition, this study aimed to determine differences in sensory characteristics between Manchego type cheeses manufactured with either hair sheep milk or cow milk. A total of 25 and 14 Manchego type cheeses from hair sheep milk and cow milk were manufactured, respectively. In addition, 30 and 15 Panela cheeses from hair sheep milk and cow milk were manufactured, respectively. The chemical composition and FA profile were determined in all cheeses. In addition, a sensory analysis was performed in Manchego type cheeses manufactured from either hair sheep milk or cow milk. Moisture content was lower in Manchego type cheeses (37.5 ± 1.26 and 37.5 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively) than in Panela cheeses (54.0 ± 1.26 and 56.1 ± 1.26 g/100 g in cheeses manufactured from hair sheep milk and cow milk, respectively). Ash, protein, and sodium contents were higher in Manchego type cheeses than in Panela cheeses. Manchego type cheese manufactured from hair sheep milk contained more C4:0, C6:0, C8:0, C10:0, C12:0, C14:0, C18:2 cis-9,cis-12, total saturated FA, total short-chain FA, total medium-chain FA, total polyunsaturated FA, and de novo FA than Manchego type cheeses from cow milk. Total content of short-chain FA was higher in hair sheep cheeses (24.4 ± 1.30 and 19.6 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively) than in cow cheeses (8.89 ± 1.30 and 8.26 ± 1.30 g/100 g in Manchego type and Panela cheeses, respectively). Manchego type cheeses from hair sheep milk obtained higher scores for odor (7.05), texture (6.82), flavor (7.16), and overall acceptance (7.16) compared with those made from cow milk (6.37, 6.12, 6.17, and 6.83, respectively). In conclusion, both Manchego type cheese and Panela cheese manufactured with hair sheep milk had a similar chemical composition and contained higher levels of short-chain FA, total polyunsaturated FA, and de novo FA than those manufactured with cow milk.

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.

Milk supplemented with dried seaweed affects the systemic innate immune response in preweaning dairy calves

Intact seaweed or seaweed extracts are used as feed supplements to improve the gut microbiome in young animals. Seaweeds provide functional polysaccharides, and they are a good source of vitamins, minerals, and phenolic compounds, all of which are relevant for immune system development. However, literature on the effects of dried seaweed supplementation on immune system development is limited, especially in calves. This experiment aimed to study the effect of feeding milk supplemented with Ulva lactuca, Ascophyllum nodosum, or Saccharina latissima on the systemic immune status of preweaning dairy calves. Forty male Holstein calves with birth body weight 41 ± 4 kg and plasma Brix percentage ≥8.7% at d 2 after birth were used in this study. Calves were fed 4 L of cow milk twice a day (total 8 L/d). From d 2 to d 28, calves in the control group (n = 10) received milk without seaweed supplementation. Over the same period, experimental calves received milk supplemented with Ulva lactuca (SW1; n = 10), Ascophyllum nodosum (SW2; n = 10), or Saccharina latissima (SW3, n = 10). Dried and ground seaweeds were offered at a daily allowance of 50 g/8 L of milk (i.e., approximately 5% inclusion rate on a dry matter basis). Blood samples were collected from a jugular vein on d 2, 4, 7, 14, 21, and 28 after birth. Plasma concentrations of total protein, albumin, immunoglobulins, and acute-phase proteins (i.e., serum amyloid A, fibrinogen, and haptoglobin) were measured. We detected no differences in average daily gain, plasma immunoglobulins, albumin, or total protein. However, the contrast analysis revealed that plasma concentrations of fibrinogen (SW1 and SW2) and serum amyloid A (SW2 and SW3) were significantly higher in the seaweed groups compared with the control group. We also found a tendency for high plasma haptoglobin in the seaweed groups (SW1 and SW2) compared with the control group. Differences in acute-phase protein concentrations could be partially explained by the large differences in micromineral intake between control and seaweed-supplemented calves. Feeding milk supplemented with dried seaweed increased plasma concentrations of variables related to the innate immune response in preweaning dairy calves.

The application of omics in ruminant production: a review in the tropical and sub-tropical animal production context

The demand for animal products (e.g. dairy and beef) in tropical regions is expected to increase in parallel with the public demand for sustainable practices, due to factors such as population growth and climate change. The necessity to increase animal production output must be achieved with better management and production technologies. For this to happen, novel research methodologies, animal selection and postgenomic tools play a pivotal role. Indeed, improving breeder selection programs, the quality of meat and dairy products as well as animal health will contribute to higher sustainability and productivity. This would surely benefit regions where resource quality and quantity are increasingly unstable, and research is still very incipient, which is the case of many regions in the tropics. The purpose of this review is to demonstrate how omics-based approaches play a major role in animal science, particularly concerning ruminant production systems and research associated to the tropics and developing countries. SIGNIFICANCE: Environmental conditions in the tropics make livestock production harder, compared to temperate regions. Due to global warming, the sustainability of livestock production will become increasingly problematic. The use of novel omics technologies could generate useful information to understand adaptation mechanisms of resilient breeds and/or species. The application of omics to tropical animal production is still residual in the currently available literature. With this review, we aim to summarize the most notable results in the field whilst encouraging further research to deal with the future challenges that animal production in the tropics will need to face.

Milk Replacer Supplementation with Docosahexaenoic Acid from Microalgae Does Not Affect Growth and Immune Status in Goat Kids

Simple Summary

The consumption of docosahexaenoic acid (DHA) has beneficial effects on human health. Meat from suckling goat kids is highly valuable, especially in Mediterranean countries. Based on this, several strategies have been implemented to increase the content of DHA in foodstuffs such as meat and meat products. Several studies have observed how feeding diverse sources of DHA can improve the fatty acid profile in goat kid meat. However, few studies have focused on the effect of using these DHA supplements on growth and the immune system development in these animals. Consequently, this study aimed to evaluate the effect of different levels of DHA supplementation on growth and the immune system development in newborn goat kids. The current study showed that the DHA supplementation did not affect either growth or the immune status of goat kids during the first 35 days of life.

Abstract

Consumption of polyunsaturated fatty acids (PUFA), especially docosahexaenoic acid (DHA), has beneficial effects for consumers’ health. Consequently, there is an increased interest in enhancing meat fatty acid profiles (i.e., PUFA and DHA content) through diverse nutritional strategies. This study aimed to investigate the effect of supplementing a microalgae-derived product rich in DHA on growth and immune system development in newborn goat kids. In this experiment, newborn goat kids were fed milk replacer (MR) supplemented with three levels of a microalgae-derived product rich in DHA (DHA-Gold^®, Martek Biosciences, MD, USA). Groups were designed as follows: MR-NS (milk replacer without DHA-Gold^® supplementation; n = 10), MR-DHA-9 (9 g of DHA-Gold^®/L milk replacer; n = 10) and MR-DHA-18 (18 g of DHA-Gold^®/L milk replacer; n = 10). The immune status of the kids was evaluated by the plasma IgG and IgM concentrations, as well as by the complement system and chitotriosidase activities. Dietary supplementation with DHA did not affect either growth or innate and humoral immunity (p > 0.05). This study concludes that supplementation with DHA does not cause negative effects on growth and immune status in newborn goat kids.

Correction to: Camelids: new players in the international animal production context

In the originally published version of the article, Figure 4 image has an error. Corrected Fig. 4 is shown below.

Oral administration of lipopolysaccharides from Escherichia coli (serotype O111:B4) does not induce an effective systemic immune response in milk-fed Holstein calves

It is well established that intravenous administration of lipopolysaccharides (LPS)-cell wall components from gram-negative bacteria-induce acute inflammatory responses in dairy calves, but the effect of oral administration of LPS to dairy calves is currently unknown. To evaluate the effects of oral administration of LPS derived from Escherichia coli (serotype O111:B4) on innate immune responses in milk-fed Holstein calves, 20 visually healthy calves (34 ± 1 d) received 4 L of milk with LPS (12 μg/kg body weight; n = 10; LPS) or without LPS (n = 10; control) at the morning feeding. Samples were collected at 0.5 h before the morning feeding and at 3, 6, 24, 48, 72, and 168 h after the morning feeding to measure rectal temperature and heart rate, as well as plasma-negative and plasma-positive acute phase proteins (i.e., haptoglobin, serum amyloid A, albumin, total protein, and fibrinogen) and immunoglobulin concentrations (IgG, IgM, and IgA). None of these measurements was affected by the oral administration of LPS. Oral administration of LPS at 12 μg/kg of body weight did not induce an acute inflammatory response in visually healthy milk-fed Holstein calves when administered in milk.

Use of glycerol and propylene glycol as additives in heat-treated goat colostrum

This experiment aimed to evaluate the suitability of glycerol and propylene glycol to reduce microbial count and preserve immune properties in heat-treated goat colostrum. Colostrum samples from 11 goats were each divided into 9 aliquots. Different concentrations (2, 6, 10, and 14%; vol/vol) of either glycerol or propylene glycol were added to the aliquots. Phosphate buffer solution was added to one aliquot, which was set as the control (CG). After the respective additions, all colostrum samples were heat treated at 56°C for 1 h. After cooling, aerobic mesophilic bacteria were cultured. The samples were frozen until free fatty acid, IgG, IgA, and IgM concentrations and chitotriosidase activity were measured. No differences were found in aerobic mesophilic bacteria counts between either 10 or 14% glycerol and propylene glycol additives. These additions reduced bacterial count to a greater extent than CG, and 2 or 6% additions. Colostrum IgG concentration was not affected by either of the additives or their concentrations. The propylene glycol additive reduced IgA and IgM concentrations and chitotriosidase activity, compared with CG. Conversely, glycerol did not affect any of the studied immune variables. In conclusion, glycerol addition to goat colostrum before heat treatment is suitable to enhance bacterial reduction, whereas colostrum immune properties were not affected.

Dairy science and health in the tropics: challenges and opportunities for the next decades

In the next two decades, the world population will increase significantly; the majority in the developing countries located in the tropics of Africa, Asia, Latin America, and the Caribbean. To feed such a population, it is necessary to increase the availability of food, particularly high-value animal protein foods produced locally, namely meat and dairy products. Dairy production in tropical regions has a lot of growth potential, but also poses a series of problems, particularly as dairy production systems were developed in temperate countries and in most cases are difficult to implement in the tropics. Drawbacks include hot weather and heat stress, the lack of availability of adequate feeds, poor infrastructure, and cold chain and the competition with cheap imports from temperate countries. This position paper reviews the major drawbacks in dairy production for the five major dairy species: cattle, water buffalo, sheep, goat, and camel, as well as the future trends in research and development. It also concerns the major trends in reproduction and production systems and health issues as well as environmental concerns, particularly those related to greenhouse gas emissions. Tropical Animal Health and Production now launches a topical collection on Tropical Dairy Science. We aim to publish interesting and significant papers in tropical dairy science. On behalf of the editorial board of the Tropical Animal Health and Production, we would like to invite all authors working in this field to submit their works on this topic to this topical collection in our journal.

Sheep and goats raised in mixed flocks have diverse immune status around parturition

Several physiological and metabolic changes take place in dairy ruminants around parturition (late pregnancy, parturition, and early lactation). Dairy species are genetically selected for their higher milk production compared with non-dairy species. This fact causes a constant stress that impairs the immune status of the animal, with consequences for its welfare and performance. In the present study, we assessed the immune status of high-yield dairy sheep and goats by quantifying IgG and IgM concentrations, as well as chitotriosidase (ChT) and complement system [total complement system (TC) and alternative complement pathway (AC)] activity in blood plasma around parturition. We also measured IgG and IgM concentrations and ChT activity in colostrum and milk during the first 40 d postpartum. The lowest blood IgG concentration was at parturition in both species. We detected no differences in blood IgG concentrations between species. Blood IgM concentrations were constant in both species throughout the study period. However, blood IgM concentrations were greater in sheep than in goats. Blood ChT activity was greater in goats than in sheep, and both species showed constant activity of this enzyme throughout the study period. We observed no differences in complement system (TC and AC) activity between sheep and goats. In addition, both TC and AC activity were constant in both species throughout the experiment. In general, IgG and IgM concentrations were greater in sheep colostrum than in goat colostrum, but these differences disappeared after d 4 (IgG) and d 3 (IgM) postpartum. In both species, the highest IgG and IgM concentrations were measured in colostrum, gradually decreasing during the first days postpartum. Chitotriosidase activity decreased in both species from colostrum to milk, although goats always showed greater ChT activity than sheep. Both sheep and goats seemed to be more susceptible to infectious diseases around parturition. As well, goats showed greater ChT activity in blood, colostrum, and milk than sheep. This fact may give these animals additional protection against parasite and fungal infections.

SWATH-MS quantitative proteomic investigation of intrauterine growth restriction in a porcine model reveals sex differences in hippocampus development

Intrauterine growth restriction (IUGR) is characterized by reduced growth and weight of the foetus, mainly due to the lack of nutrients and oxygen. Animals affected by IUGR show changes in specific brain areas and several neuronal processes. Female offspring affected by IUGR show increased survival and development compared to males. The objective of this study was to analyse changes in the hippocampus proteome in male and female piglets affected by IUGR. Seven pregnant Iberian sows were fed from Day 35 of pregnancy onwards at 50% of their requirements. At Day 100 of pregnancy, foetuses were obtained and classified by sex and weight, as mild IUGR (Normal Body Weight) versus severe IUGR (Low Body Weight). Hippocampi were dissected and the proteomes analysed by SWATH-MS DIA. In this study, 1497 proteins were identified of which 260 were quantitatively analysed. All differential proteins were more abundant in females versus males and were involved in protein synthesis, neuronal development, metabolism, antiapoptotic signalling and vesicular transport. Our findings support that female foetuses tolerate nutrient limitation better than males, especially under mild IUGR. Under severe IUGR, females still seems to maintain normal lipid metabolism and antiapoptotic signalling, which may be related to the increased female survival. SIGNIFICANCE: In the last years, proteomics have been used to evidence differences related to sex in non-reproductive organs. Intrauterine Growth Restriction (IUGR) can affect female and male offspring differently. Female offspring has stronger protective strategies compared to males, enhancing growth and postnatal survival. Most studies regarding this issue have focused on metabolic organs (i.e. liver). However, the predominance of neurodevelopmental disorders in males suggests that the central nervous system in female offspring adapt better to nutritional stress conditions than that of males. Based on the differential protein expression in hippocampal samples, our work demonstrates that female foetuses indeed adapt better to IUGR than males, especially under mild IUGR conditions. In severe IUGR conditions, differences between males and females were not so evident, but even in this case, the remaining differences suggest increased survival in females than in males.

Selected reaction monitoring mass spectrometry of mastitis milk reveals pathogen-specific regulation of bovine host response proteins

Mastitis is a major challenge to bovine health. The detection of sensitive markers for mastitis in dairy herds is of great demand. Suitable biomarkers should be measurable in milk and should report pathogen-specific changes at an early stage to support earlier diagnosis and more efficient treatment. However, the identification of sensitive biomarkers in milk has remained a challenge, in part due to their relatively low concentration in milk. In the present study, we used a selected reaction monitoring (SRM) mass spectrometry approach, which allowed the absolute quantitation of 13 host response proteins in milk for the first time. These proteins were measured over a 54-h period upon an in vivo challenge with cell wall components from either gram-negative (lipopolysaccharide from Escherichia coli; LPS) or gram-positive bacteria (peptidoglycan from Staphylococcus aureus; PGN). Whereas our data clearly demonstrate that all challenged animals have consistent upregulation of innate immune response proteins after both LPS and PGN challenge, the data also reveal clearly that LPS challenge unleashes faster and shows a more intense host response compared with PGN challenge. Biomarker candidates that may distinguish between gram-negative and gram-positive bacteria include α-2 macroglobulin, α-1 antitrypsin, haptoglobin, serum amyloid A3, cluster of differentiation 14, calgranulin B, cathepsin C, vanin-1, galectin 1, galectin 3, and IL-8. Our approach can support further studies of large cohorts of animals with natural occurring mastitis, to validate the relevance of these suggested biomarkers in dairy production.

Elevating serotonin pre-partum alters the Holstein dairy cow hepatic adaptation to lactation

Serotonin is known to regulate energy and calcium homeostasis in several mammalian species. The objective of this study was to determine if pre-partum infusions of 5-hydroxytryptophan (5-HTP), the immediate precursor to serotonin synthesis, could modulate energy homeostasis at the level of the hepatocyte in post-partum Holstein and Jersey dairy cows. Twelve multiparous Holstein cows and twelve multiparous Jersey cows were intravenously infused daily for approximately 7 d pre-partum with either saline or 1 mg/kg bodyweight of 5-HTP. Blood was collected for 14 d post-partum and on d30 post-partum. Liver biopsies were taken on d1 and d7 post-partum. There were no changes in the circulating concentrations of glucose, insulin, glucagon, non-esterified fatty acids, or urea nitrogen in response to treatment, although there were decreased beta-hydroxybutyrate concentrations with 5-HTP treatment around d6 to d10 post-partum, particularly in Jersey cows. Cows infused with 5-HTP had increased hepatic serotonin content and increased mRNA expression of the serotonin 2B receptor on d1 and d7 post-partum. Minimal changes were seen in the hepatic mRNA expression of various gluconeogenic enzymes. There were no changes in the mRNA expression profile of cell-cycle progression marker cyclin-dependent kinase 4 or apoptotic marker caspase 3, although proliferating cell nuclear antigen expression tended to be increased in Holstein cows infused with 5-HTP on d1 post-partum. Immunofluorescence assays showed an increased number of CASP3- and Ki67-positive cells in Holstein cows infused with 5-HTP on d1 post-partum. Given the elevated hepatic serotonin content and increased mRNA abundance of 5HTR2B, 5-HTP infusions may be stimulating an autocrine-paracrine adaptation to lactation in the Holstein cow liver.

NMR-metabolomics profiling of mammary gland secretory tissue and milk serum in two goat breeds with different levels of tolerance to seasonal weight loss

Goats are of special importance in the Mediterranean and tropical regions for producing a variety of dairy products. The scarcity of pastures during the dry season leads to seasonal weight loss (SWL), which affects milk production. In this work, we studied the effect of feed-restriction on two dairy goat breeds, with different tolerance levels to SWL: the Majorera breed (tolerant) and the Palmera breed (susceptible). Nuclear magnetic resonance (NMR) was used to compare the metabolome of an aqueous fraction of the mammary gland and milk serum from both breeds. Goats in mid-lactation were divided by breed, and each in two feed-regime groups: the control group and the restricted-fed group (to achieve 15-20% reduction of body weight at the end of the experiment). Milk and mammary gland samples were collected at the end of the experimental period (23rd day). (1)H NMR spectra were collected from the aqueous extract of the mammary gland biopsies and the milk serum. Profiling analysis has led to the identification of 46 metabolites in the aqueous extract of the mammary gland. Lactose, glutamate, glycine and lactate were found to be the most abundant. Analysis of milk serum allowed the identification of 50 metabolites, the most abundant being lactose, citrate and creatine. Significant differences were observed, in mammary gland biopsies and milk serum, between control and restricted-fed groups in both breeds, albeit with no differences between the breeds. Variations seem to be related to metabolism adaptation to the low-energy diet and are indicative of breed-specific microflora. Milk serum showed more metabolites varying between control and restricted groups, than the mammary gland. The Majorera breed also showed more variations than the Palmera breed in milk samples, which could be an indication of a prompt adaptation to SWL by the Majorera breed.

Increased serum serotonin improves parturient calcium homeostasis in dairy cows

Hypocalcemia in dairy cows is caused by the sudden increase in calcium demand by the mammary gland for milk production at the onset of lactation. Serotonin (5-HT) is a key factor for calcium homeostasis, modulating calcium concentration in blood. Therefore, it is hypothesized that administration of 5-hydroxy-l-tryptophan (5-HTP), a 5-HT precursor, can increase 5-HT concentrations in blood and, in turn, induce an increase in blood calcium concentration. In this study, 20 Holstein dairy cows were randomly assigned to 2 experimental groups. Both groups received a daily i.v. infusion of 1 L of either 0.9% NaCl (C group; n = 10) or 0.9% NaCl containing 1 mg of 5-HTP/kg of BW (5-HTP group, n = 10). Infusions started d 10 before the estimated parturition and ceased the day of parturition, resulting in at least 4 d of infusion (8.37 ± 0.74 d of infusion). Until parturition, blood samples were collected every morning before the infusions, after parturition samples were taken daily until d 7, and a final sample was collected on d 30. Milk yield was recorded during this period. No differences between groups were observed for blood glucose, magnesium, and β-hydroxybutyrate. Cows receiving the 5-HTP infusion showed an increase in fatty acid concentrations from d -3 to -1 before parturition. Serum 5-HT concentrations were increased at d -4 related to parturition until d 5 postpartum in the 5-HTP group compared with the C group. In addition, cows from the 5-HTP group had increased 5-HT concentrations in colostrum, but not in mature milk, on d 7 postpartum. Serum calcium concentrations decreased in both groups around parturition; however, calcium remained higher in the 5-HTP group than in controls, with a significant difference between groups on d 1 (1.62 ± 0.08 vs. 1.93 ± 0.09 mmol/L in control and 5-HTP groups, respectively) and d 2 (1.83 ± 0.06 vs. 2.07 ± 0.07 mmol/L in control and 5-HTP groups, respectively). Additionally, colostrum yield (first milking) was lower in the 5-HTP group compared with the C group, but without consequences on colostrum IgG concentrations. Milk yield did not differ between groups during the rest of the experiment. The study data were consistent with the concept that infusion of 5-HTP to dairy cows increases blood 5-HT concentrations, which in turn is a significant regulatory component in the chain of effectors that affect calcium status around parturition, hence the occurrence of clinical or subclinical hypocalcemia.

Differential glucocorticoid-induced closure of the blood-milk barrier during lipopolysaccharide- and lipoteichoic acid-induced mastitis in dairy cows

Bacteria invading the mammary gland can cause pathogen-dependent differences in the permeability of the blood-milk barrier leading to the differential paracellular transfer of blood and milk components. Glucocorticoids such as prednisolone (PRED) are known to increase the integrity of the blood-milk barrier and quickly restore the decreased milk quality associated with mastitis. The objective of this study was to examine the effect of intramammary PRED on the differential permeability of the blood-milk barrier during mastitis induced by lipopolysaccharide (LPS) from Escherichia coli or lipoteichoic acid (LTA) from Staphylococcus aureus. Thirty-one dairy cows, divided into 6 groups, were injected via a teat canal with LPS, LTA, LPS and PRED, LTA and PRED, saline (control), or PRED. Milk and blood samples were collected 0 to 8h after challenge and analyzed for somatic cell count, IgG, serum albumin, and lactate dehydrogenase in milk, or α-lactalbumin in plasma. Somatic cell count was similarly elevated in LPS- and LTA-challenged quarters and was reduced to control quarter levels only in LTA-challenged quarters with PRED administration. Lactate dehydrogenase activity was highly elevated in LPS quarters and only slightly elevated in LTA quarters, but decreased to control quarter levels with PRED administration. For serum albumin and IgG, only LPS quarters showed an elevation in concentration and PRED treatment reduced the concentration to control quarter level. We found no differences in α-lactalbumin concentrations in plasma in PRED-treated cows compared with cows that only received LPS or LTA. In conclusion, the pathogen-specific appearance of blood constituents in milk during mastitis demonstrates a differential activation of the blood-milk barrier that, in turn, can be manipulated by intramammary glucocorticoids. The results show that the administration of PRED during mastitis increases the blood-milk barrier integrity but has implications in reducing the transfer of IgG that specifically occurs during E. coli mastitis. In addition, it can also reduce the number of migrating immune cells dependent on the mastitis-inducing pathogen. Potential effects of PRED on the cure of naturally occurring mastitis have to be taken into consideration.

The Goat (Capra hircus) Mammary Gland Mitochondrial Proteome: A Study on the Effect of Weight Loss Using Blue-Native PAGE and Two-Dimensional Gel Electrophoresis

Seasonal weight loss (SWL) is the most important limitation to animal production in the Tropical and Mediterranean regions, conditioning producer’s incomes and the nutritional status of rural communities. It is of importance to produce strategies to oppose adverse effects of SWL. Breeds that have evolved in harsh climates have acquired tolerance to SWL through selection. Most of the factors determining such ability are related to changes in biochemical pathways as affected by SWL. In this study, a gel based proteomics strategy (BN: Blue-Native Page and 2DE: Two-dimensional gel electrophoresis) was used to characterize the mitochondrial proteome of the secretory tissue of the goat mammary gland. In addition, we have conducted an investigation of the effects of weight loss in two goat breeds with different levels of adaptation to nutritional stress: Majorera (tolerant) and Palmera (susceptible). The study used Majorera and Palmera dairy goats, divided in 4 sets, 2 for each breed: underfed group fed on wheat straw (restricted diet, so their body weight would be 15–20% reduced by the end of experiment), and a control group fed with an energy-balanced diet. At the end of the experimental period (22 days), mammary gland biopsies were obtained for all experimental groups. The proteomic analysis of the mitochondria enabled the resolution of a total of 277 proteins, and 148 (53%) were identified by MALDI-TOF/TOF mass spectrometry. Some of the proteins were identified as subunits of the glutamate dehydrogenase complex and the respiratory complexes I, II, IV, V from mitochondria, as well as numerous other proteins with functions in: metabolism, development, localization, cellular organization and biogenesis, biological regulation, response to stimulus, among others, that were mapped in both BN and 2DE gels. The comparative proteomics analysis enabled the identification of several proteins: NADH-ubiquinone oxidoreductase 75 kDa subunit and lamin B1 mitochondrial (up-regulated in the Palmera breed), Guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-2 (up-regulated in the Majorera breed) and cytochrome b-c1 complex subunit 1, mitochondrial and Chain D, Bovine F1-C8 Sub-Complex Of Atp Synthase (down-regulated in the Majorera breed) as a consequence of weight loss.

The colostrum proteome, ruminant nutrition and immunity: a review

In this review authors address colostrum proteins implications in different domestic ruminant species. The colostrogenesis process and how different factors, such as litter size or nutrition during gestation can alter the different components concentrations in colostrum are also reviewed. The different colostrum fractions will be described, focusing on high and low abundant proteins. This review describes the major function of such proteins and their role on the passive immune transfer and nutrition in the newborn animal. It will be also performed a comprehensive review on different techniques and commercial kits available for high abundant protein depletion in colostrum. We will finally focus on how proteomics has been used to address this issue and how it can contribute to the major questions about colostrum associated immunology.