Characterizing metabolome signature of colostrum, transition and mature milk of indigenous cows (Bos indicus) adapted to high altitude environment of Leh-Ladakh

This study has identified 46 metabolites in colostrum, transition milk and mature milk of unique indigenous high altitude adapted Ladakhi cows using 1D 1H 800 MHz NMR spectroscopy. The multivariate analysis revealed that UDP-galactose, UDP-glucose, citrate, creatine phosphate, myo-inositol, lactose, 2-oxoglutarate, valine, maltose, leucine, dimethylamine, and choline with high VIP scores could differentiate the colostrum, transition and mature milk in separate clusters. Highly enriched metabolites in colostrum such as UDP-galactose, UDP-glucose play crucial roles in cell growth, differentiation, and defense responses. Similarly, the presence of branched chain amino acids in colostrum could be linked to mammary gland development, N-acetylglucosamine, N-acetyl carnitine, choline etc. in high concentration in colostrum l might be helping in growth and development of neonatal calves of Ladakhi cows under hypoxia environment. Overall, this study has helped to characterize the metabolomic signatures of milk/colostrum of Ladakhi cows adapted to high altitude and cold desert of Leh-Ladakh.

The skimmed milk proteome of dairy cows is affected by the stage of lactation and by supplementation with polyunsaturated fatty acids

The impact of nutritional modification to increase functional polyunsaturated fatty acids (PUFA), such as n-3 and n-6 fatty acids (FA) or conjugated linoleic acid (CLA), on milk proteome profile during early lactation remains largely unknown. We used an untargeted proteomics approach to investigate the impact of lactation day and PUFA supplementation on the proteome signature in skimmed milk over the course of early lactation. Sixteen Holstein dairy cows received abomasal infusion of saturated FA (CTRL) or a mixture of essential FA and CLA (EFA + CLA group) from - 63 to + 63 days relative to parturition. Using quantitative proteomics, 479 unique proteins were identified in skimmed milk at days 1, 28, and 63 postpartum. The top discriminating proteins between transition milk (day 1) and mature milk (days 28 and 63), including members of complements (i.e. C2 and C5), growth factor (TGFB2), lipoproteins (i.e. APOE and APOD), and chaperones (i.e. ST13 and CLU), are associated with calves' immune system and gut development. The EFA + CLA supplementation moderately affected a few proteins associated with regulating mammary glands' lipogenesis through the (re)assembly of lipoprotein particles, possibly under the PPAR signaling pathway. Collectively, skimmed milk proteome is dynamically regulated initially by cow's metabolic and physiological changes and to a lesser extent by nutritional PUFA modifications.

Distinguishing Natural Infections of the Bovine Mammary Gland by Staphylococcus from Streptococcus spp. Using Quantitative Milk Proteomics

Bovine mastitis is the most frequent disease on dairy farms, which leads to a decrease in the health welfare of the animals and great economic losses. This study was aimed at determining the quantitative variations in the milk proteome caused by natural infection by Staphylococcus and Streptococcus species in order to gain further understanding of any discrepancies in pathophysiology and host immune responses, independent of the mastitis level. After identification of Staphylococcus (N = 51) and Streptococcus (N = 67) spp., tandem mass tag (TMT)-labeled quantitative proteomic and liquid chromatography-mass spectrometry (LC-MS/MS) techniques on a modular Ultimate 3000 RSLCnano system coupled to a Q Exactive Plus was applied on aseptically sampled milk from Holstein cows. Proteome Discoverer was used for protein identification and quantitation through the SEQUEST algorithm. Statistical analysis employing R was used to identify differentially abundant proteins between the groups. Protein classes, functions and functional-association networks were determined using the PANTHER and STRING tools and pathway over-representation using the REACTOME. In total, 156 master bovine proteins were identified (two unique peptides, p < 0.05 and FDR < 0.001), and 20 proteins showed significantly discrepant abundance between the genera (p < 0.05 and FDR < 0.5). The most discriminatory proteins per group were odorant-binding protein (higher in staphylococci) and fibrinogen beta chain protein (higher in streptococci). The receiver operating characteristic (ROC) curve showed that protein kinase C-binding protein NELL2, thrombospondin-1, and complement factor I have diagnostic potential for differentiating staphylococci and streptococci intramammary infection and inflammation. Improved understanding of the host response mechanisms and recognition of potential biomarkers of specific-pathogen mastitis, which may aid prompt diagnosis for control implementation, are potential benefits of this study.

Occurrence of Escherichia coli Pathotypes in Diarrheic Calves in a Low-Income Setting

Different E. coli pathotypes are common zoonotic agents. Some of these pathotypes cause recurrent and widespread calf diarrhea and contribute to significant economic losses in the livestock sector worldwide in addition to putting humans at risk. Here, we investigated the occurrence of E. coli pathotypes in diarrheic calves in Ethiopia kept under various calf management practices. One hundred fecal samples were collected from diarrheic calves in 98 different farms. E. coli was isolated in the samples from 99 of the diarrheic calves, and virulence genes were detected in 80% of the samples. The occurrence of E. coli pathotypes in the samples was 32% ETEC, 23% STEC, 18% STEC/ETEC, 3% EPEC, 2% EAEC, and 1% EHEC. No diarrheic calves were positive for the EIEC and DAEC pathotypes. The occurrence of pathotypes was positively associated with female calves (EPEC, p = 0.006), aged less than 2 weeks (STEC, p = 0.059), and calves fed colostrum via the hand method (STEC, p = 0.008 and EAEC, p = 0.003). This study revealed that several E. coli pathotypes occurred among calves affected with diarrhea. Moreover, the presence of a mixed STEC/ETEC pathotypes infection was present in the studied low-income setting. These findings indicate a considerable risk for the zoonotic transmission from calves to humans and the options to provide the better management for younger calves in order to reduce the economic loss.

Fatty acid profile characterization in colostrum, transition milk, and mature milk of primi- and multiparous cows during the first week of lactation

The specific fatty acid (FA) profile of colostrum may indicate a biological requirement for neonatal calves. The objective of this study was to characterize the FA profile and yields in colostrum, transition milk, and mature milk in primiparous (PP) and multiparous (MP) cows. Colostrum was milked from 10 PP and 10 MP Holstein cows fed the same pre- and postpartum rations. Milkings (M) 2 to 5 and 12 were respectively termed transition and mature milk. Overall, short-chain FA (C4:0 and C6:0) were 61 and 50% lower in colostrum than mature milk, respectively. A parity by milking interaction was also present, with higher C4:0 for PP cows at M2 and for MP cows at M12. Additionally, higher concentrations of C6:0 were present for PP cows at M2 through M4 and for MP cows at M12. Palmitic (C16:0) and myristic (C14:0) acids were 38% and 19% higher in colostrum than mature milk, respectively. However, total saturated FA remained relatively stable. Branched-chain FA were 13% lower in colostrum than mature milk and higher in PP than MP cows throughout the milking period. The proportion of trans-monounsaturated FA (MUFA) was 72% higher in PP cows throughout the milking period, as well as 13% lower in colostrum than mature milk. In contrast, cis-MUFA and total MUFA were not affected by milking nor parity. Linoleic acid (LA) was 25% higher in colostrum than transition and mature milks, but α-linolenic acid (ALA) did not differ. Consequently, the ratio of LA to ALA was 29% higher in colostrum than mature milk and 33% higher in MP cows. Linoleic acid was also 15% higher in MP cows, whereas ALA was 15% higher in PP cows. Conjugated linoleic acid (CLA, cis-9,trans-11) was 2.7-fold higher in PP cows, and no differences between colostrum and mature milk were detected. Overall, polyunsaturated FA (PUFA) from the n-6 and n-3 series were over 40% higher in colostrum compared with transition and mature milk. Milking by parity interactions were present for arachidonic acid (ARA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and total n-3 PUFA, translating to higher proportions in PP cows in M1 to M3, whereas proportions remained relatively stable throughout the milking period in MP cows. Despite increasing milk yields throughout the subsequent milkings, higher yields of EPA, ARA, DPA, and DHA were present in colostrum than in mature milk. Greater proportions and yields of n-3 and n-6 FA in colostrum may translate to specific requirements for newborn calves. Differences were also observed between PP and MP cows and may reflect different nutrient requirements and partitioning.

Changes in Whey Proteome between Mediterranean and Murrah Buffalo Colostrum and Mature Milk Reflect Their Pharmaceutical and Medicinal Value

Milk represents an integrated meal for newborns; its whey protein is rich in many health beneficial components and proteins. The current study aimed to investigate the differences between colostrum and mature milk from Mediterranean and Murrah buffaloes using labeled proteomics and bioinformatics tools. In the current work, LC-MS/MS analysis led to identification of 780 proteins from which 638 were shared among three independent TMT experiments. The significantly changed proteins between the studied types were analyzed using gene ontology enrichment and KEGG pathways, and their interactions were generated using STRING database. Results indicated that immunological, muscular development and function, blood coagulation, heme related, neuronal, translation, metabolic process, and binding proteins were the main terms. Overall, colostrum showed higher levels of immunoglobulins, myosins, actin, neurofascin, syntaxins, thyroglobulins, and RNA-binding proteins, reflecting its importance in the development and activity of immunological, muscular, cardiac, neuronal, and thyroid systems, while lactoferrin and ferritin were increased in mature milk, highlighting its role in iron storage and hemoglobin formation.

Fatty acid profile characterization in colostrum, transition milk, and mature milk of primi- and multiparous cows during the first week of lactation

The specific fatty acid (FA) profile of colostrum may indicate a biological requirement for neonatal calves. The objective of this study was to characterize the FA profile and yields in colostrum, transition milk, and mature milk in primiparous (PP) and multiparous (MP) cows. Colostrum was milked from 10 PP and 10 MP Holstein cows fed the same pre- and postpartum rations. Milkings (M) 2 to 5 and 12 were respectively termed transition and mature milk. Overall, short-chain FA (C4:0 and C6:0) were 61 and 50% lower in colostrum than mature milk, respectively. A parity by milking interaction was also present, with higher C4:0 for PP cows at M2 and for MP cows at M12. Additionally, higher concentrations of C6:0 were present for PP cows at M2 through M4 and for MP cows at M12. Palmitic (C16:0) and myristic (C14:0) acids were 16% and 27% higher in colostrum than mature milk, respectively. However, total saturated FA remained relatively stable. Branched-chain FA were 13% lower in colostrum than mature milk and higher in PP than MP cows throughout the milking period. The proportion of trans-monounsaturated FA (MUFA) was 42% higher in PP cows throughout the milking period, as well as 15% lower in colostrum than mature milk. In contrast, cis-MUFA and total MUFA were not affected by milking nor parity. Linoleic acid (LA) was 13% higher in colostrum than transition and mature milks, but α-linolenic acid (ALA) did not differ. Consequently, the ratio of LA to ALA was 23% higher in colostrum than mature milk and 25% higher in MP cows. Linoleic acid was also 13% higher in MP cows, whereas ALA was 15% higher in PP cows. Conjugated linoleic acid (CLA, cis-9,trans-11) was 63% higher in PP cows, and no differences between colostrum and mature milk were detected. Overall, polyunsaturated FA (PUFA) from the n-6 and n-3 series were over 25% higher in colostrum compared with transition and mature milk. Milking by parity interactions were present for arachidonic acid (ARA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), docosahexaenoic acid (DHA), and total n-3 PUFA, translating to higher proportions in PP cows in M1 to M3, whereas proportions remained relatively stable throughout the milking period in MP cows. Despite increasing milk yields throughout the subsequent milkings, higher yields of EPA, ARA, DPA, and DHA were present in colostrum than in mature milk. Greater proportions and yields of n-3 and n-6 FA in colostrum may translate to specific requirements for newborn calves. Differences were also observed between PP and MP cows and may reflect different nutrient requirements and partitioning.

Performance of Hanwoo calves fed a commercial colostrum replacer versus natural bovine colostrum

Supplying a sufficient amount of high-quality colostrum is a prevailing challenge in Hanwoo calf production systems. This study aimed to describe the efficiency of a lacteal-derived colostrum replacer versus natural bovine colostrum (from Holstein) fed to Hanwoo calves. Forty newborn Hanwoo calves (25 males and 15 females; 30.7 ± 3.15 kg body weight [mean ± standard deviation]) were blocked by sex and birth weight and fed either natural colostrum or a commercial colostrum replacer. Calves displayed a narrow difference in the evolution of body weight and structural body dimensions when they received a commercial versus natural colostrum. Minor differences existed in the starter and total dry matter consumption between calves fed natural or commercial colostrum. Although the colostrum source had no significant effects on days to first diarrhea (average of 7.6 days; p = 0.17), the duration of diarrhea was longer in natural colostrum-fed calves (3.2 vs. 4.5 days; p = 0.04). Consumption of natural colostrum resulted in greater mean serum immunoglobulin G (IgG) on day 2 (14.7 vs. 10.8 ± 0.92 mg/mL) and day 7 (8.21 vs. 5.12 ± 0.82 mg/mL) of calf life, resulting in a greater proportion of commercial colostrum-fed calves (50% vs. 15%; day 2) to experience failure of passive transfer of immunity (serum IgG < cutoff point of 10 mg/mL). Overall, growth rate, body frame development, and incidence of diarrheal disease were not different in both groups. These results suggested that the colostrum replacer product tested in this study could be an alternative to natural colostrum derived from Holstein cow in securing calf growth and health in Hanwoo calf-rearing operations.

Current Diagnostic Methods for Assessing Transfer of Passive Immunity in Calves and Possible Improvements: A Literature Review

Simple Summary

The transfer of passive immunity (TPI) from cows to calves needs to be routinely assessed on farms and in field research. The gold standard method for assessing TPI is radial immunodiffusion (RID) because it directly assesses the immunoglobulin G (IgG) concentration in calf serum samples. In addition to RID, there are several other methods available for the assessment of TPI which determine the concentration of IgG or other serum components. It is known that several components present in the colostrum are absorbed by the calves and aid passive immunity. We conducted a literature review of the methods scientifically reported by experts in the field.

Abstract

Several direct or indirect methods can be used to assess immunoglobulin G (IgG) concentrations in calves, which evaluates the transfer of passive immunity (TPI). Radial immunodiffusion (RID) is the gold standard method to measure serum IgG in bovines. Previous studies have shown that colostrum provides several molecules in addition to immunoglobulins, which play an important role in the passive immunity of the calf. However, no studies have yet determined the level of interference of these components in the immunity, health and survival of calves. In this sense, the objective of this study is to review the methods of evaluation available for the laboratory and field diagnosis of TPI in calves and discuss the main aspects of each technique. Several methods available for TPI evaluation in calves may provide insights into the various components of colostrum involved in passive immunity.

Effects of colostrum management on transfer of passive immunity and the potential role of colostral bioactive components on neonatal calf development and metabolism

Neonatal dairy and beef calves are required to ingest adequate volumes of high-quality colostrum during their first hours of life to acquire transfer of passive immunity (TPI). As such, immunoglobulin G (IgG) has largely been the focus of colostrum research over recent decades. Yet, little is known about the additional bioactive compounds in colostrum that potentially influence newborn calf development and metabolism. The purpose of this narrative review is to synthesize research regarding the effects of colostrum management practices on TPI, as well as to address the potential role of additional colostral bioactive molecules, including oligosaccharides, fatty acids, insulin, and insulin-like growth factor-I, in promoting calf development and metabolism. Due to the importance of IgG in ensuring calf immunity and health, we review past research describing the process of colostrogenesis and dam factors influencing the concentrations of IgG in an effort to maximize TPI. We also address the transfer of additional bioactive compounds in colostrum and prepartum management and dam factors that influence their concentrations. Finally, we highlight key areas of future research for the scientific community to pursue to ultimately improve the health and welfare of neonatal dairy calves.

Calf health from birth to weaning - an update

Research on calf health and welfare has intensified in the past decades. This is an update on a review series on calf health from birth to weaning published ten years ago.

Good colostrum management is still recognised as the single most important factor to preventing calf morbidity and mortality, however, it is now known that immunoglobulins are only one of many components of colostrum that are vital for the calf’s development. Other non-nutrient factors like leucocytes, hormones and growth factors, oligosaccharides as well as microRNAs have significant effects on the development and maturation of the intestinal and systemic immune functions. They also promote the maturation and function of the intestine, thus enabling the calf to digest and absorb the nutrients provided with colostrum and milk. The improved energetic status of colostrum-fed neonates is reflected by an accelerated maturation of the somatotropic axis, which stimulates body growth and organ development. Colostrum oligosaccharides are presumed to play a major role in the development of a healthy intestinal flora.

A biologically normal (intensive) milk-feeding programme is subsequently necessary for optimal body growth, organ development and resistance to infectious diseases. Ad-libitum or close to ad-libitum feeding in the first three to four weeks of life also leaves calves less hungry thus improving calf welfare. Only calves fed intensively with colostrum and milk are able to reach their full potential for performance throughout their life.

Public interest in farm animal welfare is growing in past decades, which makes it necessary to have a closer look at contentious management practices in the dairy industry like early separation of the dairy calf from the dam with subsequent individual housing. Public objection to these practices cannot be mitigated through educational efforts. Contrary to common opinion there is no evidence that early cow-calf separation is beneficial for the health of calf or cow. There is evidence of behavioural and developmental harm associated with individual housing in dairy calves, social housing improves feed intake and weight gains, and health risks associated with grouping can be mitigated with appropriate management.

In conclusion, there are still many management practices commonly applied, especially in the dairy industry, which are detrimental to health and welfare of calves.

The effect of lactic acid fermentation with different bacterial strains on the chemical composition, immunoreactive properties, and sensory quality of sweet buttermilk

This paper describes the successful development of new low-immunoreactive buttermilk (BM)-based formulations which were fermented with 31 lactic acid bacteria (LAB) and Bifidobacterium strains. The aim of this study was to create a new formula, which can serve as potential candidates for the immunotherapy of allergy. Preparations were tested for their content of biologically active compounds, such as proteins, peptides, phospholipids, and short-chain fatty acids (SCFA), as well as for the survivability of LAB and sensory quality. The results showed that the BM was a matrix rich in nutritional components and displayed higher than expected susceptibility to the reduction of protein IgE-immunoreactivity (to 98%) and high bacterial-protecting capacity. The overall sensory quality of examined products was influenced by the profile of SCFA and free peptides, but two formulations fermented with Lactobacillus delbrueckii ssp. bulgaricus-151 and Lactobacillus casei-LcY were the most advantageous with desirable sensory, immunoreactive, and biochemical properties.

Innate and humoral immune parameters at delivery in colostrum and calves from heifers experimentally infected with Neospora caninum

Neospora caninum is a leading cause of abortion in cattle worldwide. The study of the immune response against N. caninum is critical to understand its epidemiology, pathogenesis, diagnosis and, ultimately, in preventing and controlling bovine neosporosis. Herein, we determined the gene expression of innate immune components endosomal RNA-sensing TLRs, BMAP28 cathelicidin, TNF-α and IL-10 and characterized the variation in both IgG ratio and avidity at delivery in N. caninum-infected heifers challenged at day 210 of gestation, colostrum and their calves. Increased BMAP28 expression was observed not only in colostrum but also in peripheral blood mononuclear cells (PBMC) and umbilical cord of calves from N. caninum-infected heifers in comparison with mock-infected control group. In addition, statistically significant decrease of TLR7 and IL-10 expression levels were observed in umbilical cord, suggesting an attempt to avoid an exacerbated immune response against the parasite. At delivery, serum and colostrum samples from infected group evidenced specific IgG anti-N. caninum. Infected heifers showed IgG₁/IgG₂ ratios <1 and high avidity specific IgG. As expected, colostrum samples of these animals exhibited a high IgG₁ concentration and elevated avidity values. Three out of four calves from N. caninum-infected heifers had specific IgG with IgG₁/IgG₂ ratios>1 and lower avidity values before colostrum intake. Interestingly, both IgG₁/IgG₂ ratios and avidity values increased in seropositive calves after colostrum intake. Overall, this study provides novel information on neonatal immunity in congenitally infected calves, which is essential to understand how the immune pathways could be manipulated or immune components could be employed in order to improve protection against neosporosis.

Label-free quantitative proteomics analysis reveals the fate of colostrum proteins in the intestine of neonatal calves

The contribution of intestinally absorbed colostral immunoglobulins to the transmission of passive immunity is widely reported in neonatal calves. However, changes in the colostral proteome in the gastrointestinal digesta remain unclear. Therefore, this study aimed to investigate changes in colostral proteome affected by gastrointestinal proteases in neonatal calves. Twenty-one neonatal Holstein calves were used in this study, including 18 colostrum-fed calves slaughtered at 8 (CI, n = 6), 24 (CII, n = 6), and 36 h (CIII, n = 6) postpartum and 3 milk-fed calves slaughtered 24 h postpartum (MI, n = 3). The ingested colostrum and milk samples were collected from the mid-jejunum segment, following the sacrifice. The undigested colostrum or milk along with their ingested colostrum or milk samples were investigated using a label-free proteomics approach. Hierarchical clustering and principal component analysis of the quantified proteins revealed that the ingested colostrum from the CII and CIII groups and the ingested mature milk from the MI group appeared to share similar patterns. Analysis of the intestinal digesta revealed a time-dependent decrease in caseins, lactoferrin, and osteopontin protein levels, and an increase in cationic trypsin, chymotrypsin, and carboxypeptidase. Several protease inhibitors, such as α-1-antiproteinase, α-2-antiplasmin, and early lactation protein, were identified in the colostrum and intestinal digesta. In addition, we detected identical levels in the intestinal digesta and colostrum for albumin, α-1-acid glycoprotein, and plasminogen. Pathway analysis indicated that proteins increased in the intestinal digesta belonged to the following categories: biosynthesis of antibiotics, carbon metabolism, and biosynthesis of amino acids. These results indicated that selected colostral proteins were digested by gastrointestinal proteases, contributing to their intestinal absorption in calves. These findings provide new insights into the fate of the colostral proteome in the gastrointestinal tract and may aid in the identification of factors contributing to health management in neonatal calves.

Heat treatment of bovine colostrum: II. Effects on calf serum immunoglobulin, insulin, and IGF-I concentrations, and the serum proteome

In-depth analysis of colostrum components has identified hundreds of proteins, but data are sparse regarding their systemic uptake in the newborn calf. Moreover, heat treatment may influence these colostral components and their absorption. Our objectives were to describe the serum proteome of newborn calves before and after colostrum feeding and the possible effects of colostral heat treatment. Newborn Holstein heifer calves (n = 22) were randomized within pair and fed heat-treated (n = 11; 60°C, 60 min) or raw (n = 11) colostrum at 8.5% of birth body weight by esophageal feeder within 1 h of birth. After the single colostrum feeding, calves were not fed until after the 8-h time point, when milk was offered free-choice. Blood samples were taken immediately before feeding (0 h), as well as 4, 8, and 24 h after feeding. Whole blood packed cell volume (%), serum Brix percentage, and plasma glucose concentrations were determined for all time points. Plasma insulin and insulin-like growth factor-I concentrations were determined by radioimmunoassay for selected time points. Serum IgA and IgG were measured by radial immunodiffusion at 24 h. The serum proteome was analyzed using nano-scale reverse-phase chromatography and tandem mass spectrometry (nano LC-MS/MS) in 0- and 8-h samples. For proteomics analysis, ratios of results for 8-h to 0-h samples were analyzed with false discovery rate adjustment. For all other outcomes, repeated-measures ANOVA was performed with the fixed effects of group, time, and their interaction, and random effect of pair. Serum Brix percentage and glucose concentrations increased over time and were independent of colostrum treatment. Serum IgG and IgA concentrations at 24 h did not differ between groups. Nano LC-MS/MS identified a total of 663 unique proteins in serum, of which 261 increased in abundance, whereas 67 decreased in abundance after feeding in both groups. Among serum proteins that increased in abundance and that were previously identified in colostrum, many belonged to those involved in immune response, coagulation, the classical complement pathway, or the antimicrobial peptide class of cathelicidins. Serum proteins that decreased in abundance and that were identified in colostrum belonged to the alternative complement pathway and the membrane attack complex. Thirty-eight proteins differed in calves that were fed heat-treated colostrum compared with those fed raw colostrum. Decreased abundances in calves fed heat-treated colostrum included several enzymes involved in glycolysis or glycogenolysis, whereas the incretin gastric inhibitory polypeptide and serum insulin were increased in this group. Our findings point to important innate immune defense pathways associated with colostrum ingestion in newborn calves. Furthermore, calves fed heat-treated colostrum showed differences in serum proteins and enzymes associated with carbohydrate metabolism.

Heat treatment of bovine colostrum: I. Effects on bacterial and somatic cell counts, immunoglobulin, insulin, and IGF-I concentrations, as well as the colostrum proteome

The objective of this study was to investigate the effects of heat treatment on colostral low-abundant proteins, IgG and IgA, insulin, and insulin-like growth factor I (IGF-I), as well as bacteria and somatic cells. First-milking colostrum samples >8 L and Brix % > 22.0 were harvested from 11 Holstein cows on a commercial dairy in New York State and split into 2 aliquots using single-use colostrum bags. One aliquot of each pair was cooled on ice immediately after harvest (raw, R; n = 11), and the other was heat-treated for 60 min at 60°C (heat, H; n = 11). All samples were analyzed for IgG and IgA via radial immunodiffusion assay and insulin and IGF-I concentrations by radioimmunoassay. Total bacterial counts and somatic cell counts (SCC) were determined using standard plate culture techniques and flow cytometry, respectively. Samples from a subset of 5 pairs (n = 10) were further analyzed by nano liquid chromatography-tandem mass spectroscopy, after ultracentrifugation at 100,000 × g for 60 min at 4°C to enrich the low-abundant protein whey fraction. Data were analyzed using either paired t-test or Wilcoxon signed-rank test or using an online software package to analyze proteomics data. Outcomes of proteomics analysis were fold change ≥1.5 between pairs, and paired t-tests with false discovery rate-adjusted P-value < 0.05. The median reduction of IgA concentrations was 8.5% (range: 0-38.0%) due to heat treatment, whereas IgG concentrations did not change due to treatment. Insulin concentrations decreased by a median of 22% (7-45%), and IGF-I decreased by 10% (0-18%) in H samples. Heat treatment was associated with a median reduction of SCC of 36% (0-90%) in paired samples, as well as a median reduction in total bacterial count of 93% (45-100%) in H versus R samples. Proteomics analysis identified a total of 328 unique proteins that were present in all 10 samples. Nine of the 25 proteins that decreased by at least 1.5-fold in H compared with R were identified as complement proteins. We conclude that heat treatment of colostrum is associated with a reduction in the concentration of bacterial counts and SCC, IgA, insulin, and IGF-I. In addition, proteomics analysis of colostral whey identified several complement components and other proteins that decreased in abundance due to heat treatment. Although IgG concentrations were unaffected and a reduction in bacterial counts was achieved, the change in several immunologically active proteins and growth factors may have biologically important effects on the developing immune system of the neonate fed heat-treated colostrum.

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.

Review: Importance of colostrum supply and milk feeding intensity on gastrointestinal and systemic development in calves

Feeding management of the postnatal and preweaning calf has an important impact on calf growth and development during this critical period and affects the health and well-being of the calves. After birth, an immediate and sufficient colostrum supply is a prerequisite for successful calf rearing. Colostrum provides high amounts of nutrient as well as non-nutrient factors that promote the immune system and intestinal maturation of the calf. The maturation and function of the neonatal intestine enable the calf to digest and absorb the nutrients provided by colostrum and milk. Therefore, colostrum intake supports the start of anabolic processes in several tissues, stimulating postnatal body growth and organ development. After the colostrum feeding period, an intensive milk feeding protocol, that is, at least 20% of BW milk intake/day, is required to realise the calf potential for growth and organ development during the preweaning period. Insufficient milk intake delays postnatal growth and may have detrimental effects on organ development, for example, the intestine and the mammary gland. The somatotropic axis as the main postnatal endocrine regulatory system for body growth is stimulated by the intake of high amounts of colostrum and milk and indicates the promotion of anabolic metabolism in calves. The development of the forestomach is an important issue during the preweaning period in calves, and forestomach maturation is best achieved by solid feed intake. Unfortunately, intensive milk-feeding programmes compromise solid feed intake during the first weeks of life. In the more natural situation for beef calves, when milk and solid feed intake occurs at the same time, calves benefit from the high milk intake as evidenced by enhanced body growth and organ maturation without impaired forestomach development during weaning. To realise an intensive milk-feeding programme, it is recommended that the weaning process should not start too early and that solid feed intake should be at a high extent despite intensive milk feeding. A feeding concept based on intensive milk feeding prevents hunger and abnormal behaviour of the calves and fits the principles of animal welfare during preweaning calf rearing. Studies on milk performance in dairy cows indicate that feeding management during early calf rearing influences lifetime performance. Therefore, an intensive milk-feeding programme affects immediate as well as long-term performance, probably by programming metabolic pathways during the preweaning period.

Effects of colostrum instead of formula feeding for the first 2 days postnatum on whole-body energy metabolism and its endocrine control in neonatal calves

Colostrum provides high amounts of nutritive and non-nutritive substrates, which are essential for calf nutrition and passive immunization. Colostral growth factors and hormones have beneficial effects on postnatal maturation and may affect substrate utilization and energy expenditure in neonatal calves. We tested the hypothesis that energy metabolism and its endocrine regulation differ during the first 10 d of life in calves fed either colostrum or a milk-based formula with a similar nutrient composition to colostrum, but largely depleted of bioactive substances, for the first 2 d postnatum. Male Holstein calves (n = 18) were fed either pooled colostrum (COL; n = 9) or a milk-based formula (FOR; n = 9) for the first 2 d of life. From d 3 on, all calves received same milk replacer. On d 2 and 7 of life, calves were placed in a respiration chamber for indirect calorimetric measurements to calculate heat production, fat (FOX) and carbohydrate oxidation (COX), as well as respiratory quotient. Blood was sampled on d 1 before first colostrum intake and on d 2, 3, 7, 8, 9, and 10 before morning feeding, to measure plasma concentrations of immunoglobulins, metabolites, and hormones. Additional postprandial blood samples were taken on d 1 and 9 at 30, 60, 120, 240, and 420 min after milk feeding. Liver samples were collected on d 10 of life to determine gene expression related to energy metabolism. Formula-fed calves showed lower plasma concentrations of total protein, immunoglobulins, haptoglobin, leptin, adiponectin, and insulin-like growth factor (IGF) binding protein (IGFBP)-4 during the whole study but temporarily higher plasma concentrations of urea, insulin, glucagon, triglyceride, and cholesterol on the first day after feeding, compared with concentrations in COL. The temporary increase in glucagon, triglyceride, and cholesterol on d 1 reversed on d 2 or 3, showing higher concentrations in COL than in FOR calves. In FOR, IGF-I, IGFBP-2, and IGFBP-3 were lower on d 3 than in COL. Interestingly, FOR calves had higher heat production during respiratory measurements on d 2 and higher body temperature on d 2, 3, and 5 than those of COL. The hepatic mRNA abundance of cytosolic phosphoenolpyruvate carboxykinase was higher in FOR than in COL. Our results indicate that first milk feeding after birth influenced whole-body energy expenditure but not FOX and COX in neonatal calves, and the absorption of colostral leptin and adiponectin might affect insulin sensitivity on d 1 of life.

Characterization of the colostrum and transition milk proteomes from primiparous and multiparous Holstein dairy cows

Colostrum plays a vital role in the nutrition, development, and immunity of a newborn calf. This study aimed to characterize the protein profile of colostrum and to identify changes in the colostrum proteome across parity during the transition to mature milk. Colostrum and transition milk samples were collected at milkings 1, 2, 4, and 14 after calving from multiparous (n = 10) and primiparous cows (n = 10). Samples were skimmed, fractionated, and enriched before analysis for low-abundance proteins by liquid chromatography-tandem mass spectroscopy (LC-MS/MS). Changes in protein abundances were analyzed using PROC MIXED in SAS (SAS Institute Inc., Cary, NC) with determination of the adaptive false discovery rate adjustment using a MULTTEST procedure to identify effects of parity (P), milking number (MN), and their interaction (MN×P). We identified 86 proteins through LC-MS/MS, including 3 low-abundance proteins that were affected by P, 78 that were affected by MN, and 36 affected by MN×P. Prominent ontological groupings of proteins affected by MN included defense or immunity proteins, such as immunoglobulins. Proteins involved in the plasminogen activating cascade and more broadly, blood coagulation, were affected by MN×P. The results of this study add to increasing knowledge of the colostrum and transition milk proteomes, and this is the first study to find evidence of different abundances of these proteins when examined across P, MN, and MN×P. These findings aid in the identification of potential milk protein biomarkers for mammary health during the early postpartum period.

Changes in whey proteome with lactation stage and parity in dairy cows using a label-free proteomics approach

Milk yield and several components of milk that are affected by physiological factors have been widely investigated. However, the effects of lactation stage and parity on bovine milk whey proteins have not been well elucidated. To aid in unraveling the proteome profile and exploring the protein biosynthesis of mammary glands, a label-free proteomic approach was used to characterize whey proteomes depending on the lactation stage and parity of dairy cows. The results of this study show that the abundances of several proteins, such as early lactation protein, syntenin, and heparanase, were associated with specific stages of the lactation cycle; this was evidenced by a principal component analysis. In addition, several proteins, such as hemoglobin subunits beta and alpha, β-lactoglobulin, CD320, and apolipoprotein E, corresponded to the parity of the dairy cows and were herein considered as useful biomarkers to distinguish different parities. Most of the differentially expressed proteins from specific lactation stages and parity milk groups were annotated in the response to stimulus and protein metabolic processes. The findings reveal that developmental changes in whey proteomes correspond to lactation stages and parities, which in turn provides new insight into the underlying implications of the production of specific proteins to meet the health benefits of offspring and host, and allow us to explore the mechanisms of protein biosynthesis in mammary glands associated with physiological changes in dairy cows.

Milk proteome from in silico data aggregation allows the identification of putative biomarkers of negative energy balance in dairy cows

A better knowledge of the bovine milk proteome and its main drivers is a prerequisite for the modulation of bioactive proteins in milk for human nutrition, as well as for the discovery of biomarkers that are useful in husbandry and veterinary medicine. Milk composition is affected by lactation stage and reflects, in part, the energy balance of dairy cows. We aggregated the cow milk proteins reported in 20 recent proteomics publications to produce an atlas of 4654 unique proteins. A multistep assessment was applied to the milk proteome datasets according to lactation stages and milk fractions, including annotations, pathway analysis and literature mining. Fifty-nine proteins were exclusively detected in milk from early lactation. Among them, we propose six milk proteins as putative biomarkers of negative energy balance based on their implication in metabolic adaptative pathways. These proteins are PCK2, which is a gluconeogenic enzyme; ACAT1 and IVD, which are involved in ketone metabolism; SDHA and UQCRC1, which are related to mitochondrial oxidative metabolism; and LRRC59, which is linked to mammary gland cell proliferation. The cellular origin of these proteins warrants more in-depth research but may constitute part of a molecular signature for metabolic adaptations typical of early lactation.

Effect of calorific intake on proteomic composition of colostrum in dairy cows

The amount of concentrated feed supplied to a dairy cow affects milk yield. However, there is no evidence of a relationship between the colostrum proteomic composition and energy intake. We supplied 30 heifers (4–24 months old, two groups of 15 heifers each) with either a normal diet and high-energy diet to investigate the correlation between energy intake and colostrum protein composition. Colostrum milk proteins were analysed on the day of calving and on the third day following calving using two-dimensional gel electrophoresis (2-DE) and peptide mass fingerprinting (PMF). Five proteins were identified as differentially expressed between the two feeding groups in the colostrum on the day of calving. The levels of αS2-casein precursor and β-casein was higher in the colostrum from the high-energy diet group (HEG), whereas the levels of IgG3 heavy chain constant region, non-classical MHC class I antigen isoform X2, and β-casein A2 variant were higher in the normal-diet group (NEG) colostrum. Twelve differential proteins were identified on the third day: β-lactoglobulin, αS2-casein, zinc-α2-glycoprotein, lactoferrin, fibrinogen gamma-B chain isoform X1, non-classical MHC class I antigen isoform X2, complement C3, gelsolin isoform A precursor, vitamin D-binding protein isoform X1, immunoglobulin gamma 1 heavy chain constant region, IgG3 heavy chain constant region and polymeric immunoglobulin receptor. All were present at higher levels in the normal-diet group colostrum than in the high-energy diet group colostrum, although the milk yield from mature cows was lower in the normal-diet group. In conclusion, a high-energy diet can enhance milk production; however, the levels of immune-related factors are higher in the colostrum of cows fed a normal diet.

Changes in the content of immunostimulating components of colostrum obtained from dairy cows at different levels of production

BACKGROUND

Recent data indicate that almost 60% of colostrum samples do not have enough antibodies to provide adequate protection for the calf. Thus, the aim of this study was to determine the influence of the level of production of cows on the content of immunostimulating components of protein fraction of colostrum. The observations were conducted on two farms that keep dairy cows. One of the farms was selected to represent a typical performance level for the mass population of dairy cows in Poland, about 5500 kg of milk per cow per year (LI) and the second one was characterized by a higher level of production, about 8000 kg (HI).

RESULTS

Based on the data obtained, 100% of the samples collected from LI had an immunoglobulin G (IgG) content >50 gL^-1 , in the first collection. In the case of HI, 63% of the samples had an IgG content >50 gL^-1 , with a distribution in the range of 10.7 to 72.7 gL^-1 . The colostrum of LI cows was characterized by a higher content of lactoferrin, lysozyme, α-lactalbumin, and β-lactoglobulin compared to the milk of HI cows.

CONCLUSIONS

The immunostimulating components of colostrum declined rapidly in subsequent milkings or with the increased productivity of the cows. The concentration of IgG was negatively correlated with the performance level of cows, which means that high-producing cows had colostrum with a low concentration of IgG. © 2018 Society of Chemical Industry.