Plasma Of Cows Research Articles

Comparison of 0.46% calcium diets with and without added anions with a 0.7% calcium anionic diet as a means to reduce periparturient hypocalcemia

Most studies demonstrating that diets with low dietary cation-anion difference (DCAD) reduce hypocalcemia in cows add enough anions to the diet to reduce urine pH below 7.0. One objective of these experiments was to determine whether there is any benefit to periparturient plasma Ca concentration if diet anion addition results in a lesser degree of acidification of the cow and urine pH does not go below 7.0. Another method for reducing hypocalcemia involves feeding a prepartal diet that is Ca deficient. This places the cow in negative Ca balance before calving, stimulating parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D secretion before calving and thus promoting Ca homeostasis at calving. As practiced in the field, low-Ca diets are often about 0.5% Ca. Our second objective was to determine whether a 0.46% Ca diet would be sufficiently low in Ca to stimulate PTH secretion before calving. A meta-analysis of the literature suggests that a 0.5% Ca, low-DCAD diet will reduce hypocalcemia better than a 0.7% Ca diet. A third objective was to compare periparturient plasma Ca in cows fed 0.46 or 0.72% Ca diets with similar DCAD. In experiment 1, anions (primarily chloride) or anions plus Ca were added to a 1.4% K basal diet to create the following diets: 0.46% Ca and +167 mEq/kg of DCAD, 0.46% Ca and -13 mEq/kg of DCAD, and 0.72% Ca and -17 mEq/kg of DCAD. In experiment 2, the same amounts of anion were added to a 2.05% K basal diet to create the following diets: 0.46% Ca and +327 mEq/kg of DCAD, 0.46% Ca and +146 mEq/kg of DCAD, and 0.72% Ca and +140 mEq/kg of DCAD. In experiment 1, cows fed the diet with 0.46% Ca and +167 mEq/kg of DCAD had significantly lower plasma Ca concentration after calving than cows fed the 0.46 or 0.72% Ca diets with anions. Periparturient plasma Ca concentrations did not differ in cows fed the low-DCAD diets with 0.46 or 0.72% Ca. Urine pH was reduced from 8.27 in the diet with 0.46% Ca and +167 mEq/kg of DCAD to 7.07 and 7.41 in the 0.46 and 0.72% Ca anion diets, respectively. Precalving plasma PTH and 1,25-dihydroxyvitamin D concentrations were similar in cows fed the 0.46% Ca diets and the 0.72% Ca diets, suggesting that the 0.46% Ca diets were not low enough in Ca to place the cow in negative Ca balance before calving. In experiment 2, adding the anion supplements to a 2.05% K diet did not reduce urine pH below 8.0. Periparturient plasma Ca concentrations did not differ in cows in any group in experiment 2. Precalving diets that are 0.46% Ca fed ad libitum are too high in Ca to stimulate Ca homeostasis before calving. Adding anions to a diet can benefit periparturient cow plasma Ca concentration, but only if it alters acid-base status enough to reduce urine pH below 7.5.

Cortical regulation of content of TBA-active products in cow blood plasma

Cortical mechanisms of regulation of the content of TBC-active products in the cow’s organism depending on the season are given in the article. Experiments were carried out on cows of Ukrainian black-and-rumped breed of second-third lactation of different types of higher nervous activity. It is established that in cows with a weak type of higher nervous activity, the content of TBA-active products in blood plasma is higher than in strong cows. Thus, in the summer, this indicator in animals of the weak type of higher nervous activity was higher by 18.0% (P < 0.01) in accordance with the indicators of animals of a strong, balanced, mobile type of higher nervous activity. At the same time, in winter, the content of TBA-active products in the plasma of blood of animals of the weak type of higher nervous activity is greater by 13.0% compared to the indicators of strong, balanced, mobile type cows. The effect of cortical processes on the content of TBA-active products in the summer is – ɳ2х = 0.28 (P < 0.05), but in winter it decreases to an average of ɳ2х = 0.17. The equilibrium of the cortical processes significantly influenced the TBA- active products content, both in the summer and in winter, è2x2 = 0.24–0.30 (P < 0.05). The mobility of cortical processes does not have a significant effect on the content of TBK-active products. Reliable influence of the type of higher nervous activity (F = 3.86 > FU = 3.01; p = 0.02) on the content of TBC-active products in the blood plasma of cows was established. Then, as the season does not limit the content of TBA-active products in the blood plasma of cows (F = 2.18 <FU = 4.26; p = 0.15). It is proved that the time of year does not affect the main characteristics of cortical processes (F = 0.09 < FU = 3.0; p = 0.96). But only the effect of cortical processes in summer directly correlates with the content of TBA-active products in the blood plasma of cows (r = -0.67; P < 0,05). Thus, the influence of the type of higher nervous activity on the content of TBA-active products in the plasma of cows in different seasons is established. In animals with a weak type of higher nervous activity, a higher content of TBA-active products in plasma was detected.

Effect of dietary vitamin D3 and 25-hydroxyvitamin D3 supplementation on plasma and milk 25-hydroxyvitamin D3 concentration in dairy cows

Milk enriched with vitamin D by supplementing dairy cow diets could provide a valuable dietary source of vitamin D, but information on the feasibility of this approach is limited. In the current study, the effects of supplementing dairy cows with either vitamin D3 or 25(OH)D3 over the transition/early lactation period on plasma and milk vitamin D concentrations were compared. Sixty dairy cows were randomly allocated to 1 of 4 dietary treatments from 14 d precalving to 56 d postcalving. Treatments were a control diet (control) for both precalving and postcalving periods containing 0.625 mg/d of vitamin D3; a precalving diet supplemented with 6 mg of 25(OH)D3/d, but with a postcalving diet matching that of the control diet [25(OH)D3 precalving]; the control diet precalving but with the postcalving diet supplemented with 2 mg of vitamin D3/d (D3max), and the control diet precalving but with the postcalving diet supplemented with 1.5 mg of 25(OH)D3/d [25(OH)D3 postcalving]. No treatment effect on milk yield, composition or 25(OH)D3 concentration was observed. However, an interaction was observed of treatment and time for plasma 25(OH)D3 concentration; this increased within 2 wk of supplementation for the 25(OH)D3 precalving treatment (peaking just after calving, 202 ng/mL), whereas that of the 25(OH)D3 postcalving group had a slower response following supplementation, continuing to increase at 56 d. Correlations were observed between plasma and milk 25(OH)D3 concentrations at d 4 and 14 of lactation, but not at later sampling times. The D3max treatment did not increase 25(OH)D3 concentration in plasma or milk. Overall, results from this study indicate that supplemental 25(OH)D3 is an effective means of enhancing dairy cow plasma 25(OH)D3 concentrations compared with vitamin D3 supplementation, but not necessarily milk concentrations.

Effect of dietary propylene glycol or anti-ketosis supplement on biochemical parameters of cows blood plasma

Experiment was carried out in 6 groups of Ukrainian dairy black-and-white cows of 5 animals in a group. Cows were divided into 2 subgroups of 15 animals, each of one formed 3 groups: 1 control and 2 experimental. The diet of the first subgroup contains a soybean meal, and the second – a similar amount of soybean cake. To the ration of cows of 2-nd and 3-rd group propylene glycol or new developed dietary supplement were added. The trial lasted during the last month of the dry period and the first month of lactation. Addition of propylene glycol increased the concentration of glucose in the cows blood plasma (P < 0.05). Adding propylene glycol to the diet with soybean meal reduces the triacylglycerol content in the plasma by 21.22% (P < 0.05), addition of complex supplement to this diet, on the contrary, increases the content of triacylglycerols by 21.21% (P < 0.05). On the diet with soybean meal, propylene glycol and complex supplement reduced the amount of non-esterified fatty acids by 14.29% and 21.43% (P < 0.05), while with the soybean cake diet these differences were 21.22 and 40.39% (P < 0.05–0.001). Under the influence of feeding propylene glycol and the complex supplement, the total amount of ketone bodies in the blood plasma of cows consuming the soybean meal diet decreased 1.65 and 1.75 times (P < 0.001), and in the plasma of cows fed soybean cake diet 1.71 and 1.80 times (P < 0.001).

Hydroxy-selenomethionine: A novel organic selenium source that improves antioxidant status and selenium concentrations in milk and plasma of mid-lactation dairy cows

This study aimed to evaluate the effect of hydroxy-selenomethionine (HMSeBA), a novel organic selenium (Se) source, on milk performance, antioxidative status, and Se concentrations in the milk and plasma of mid-lactation dairy cows compared with that of sodium selenite (SS). Fifty mid-lactation dairy cows with similar days in milk, milk yield, and parity received the same basal diet containing 0.06 mg of Se/kg of DM. They were assigned to 1 of 5 treatments according to a randomized complete block design: negative control (without Se supplementation), SS supplementation (0.3 mg of Se/kg of DM; SS-0.3) or HMSeBA supplementation (0.1, 0.3, or 0.5 mg of Se/kg of DM: SO-0.1, SO-0.3, and SO-0.5, respectively). The experiment lasted for 10 wk, including a pretrial period of 2 wk. The results indicated that neither Se supplementation nor Se source affected dry matter intake, milk yield, milk composition, or blood biochemical parameters, except for milk fat percentage. Simultaneously, milk fat percentage and milk fat yield increased linearly as the quantity of HMSeBA supplementation was increased. Production of 4% FCM and ECM was elevated linearly as dietary HMSeBA increased. The SO-0.3 group showed higher serum activity of glutathione peroxidase, total antioxidant capacity, and superoxide dismutase than the SS-0.3 group, but malondialdehyde content was not affected by Se source. Furthermore, HMSeBA supplementation linearly increased the activities of serum glutathione peroxidase and superoxide dismutase, but decreased malondialdehyde content. Compared with the SS-0.3 group, the SO-0.3 group showed augmented concentrations of total Se in milk and plasma, and total Se milk-to-plasma concentration ratio. In addition, increasing doses of HMSeBA linearly increased the concentrations of total Se in the milk and plasma. This study demonstrates that HMSeBA improves antioxidant status and increases milk and plasma Se concentrations more effectively than SS, indicating that HMSeBA could replace SS as an effective organic Se source for lactating dairy cows.

Expression of hepatic genes related to energy metabolism during the transition period of Holstein and F1 Holstein-Gir cows

The aim of this study was to investigate the expression of genes encoding enzymes and other factors involved with carbohydrate and lipid metabolism in the liver of 2 genetic groups of dairy cows during the transition period. We analyzed the expression of glucose-6-phosphatase (G6PC), cytosolic phosphoenolpyruvate carboxykinase (PEPCK-C), methylmalonyl-CoA mutase (MUT), β-hydroxybutyrate dehydrogenase-2 (BDH2), acetyl-CoA carboxylase (ACC), carnitine palmitoyltransferase-2 (CPT2), 3-hydroxy-3-methylglutaryl-CoA reductase (HMGCR), glucose transporter-2 (SLC2A2), and the transcription factor peroxisome proliferator-activated receptor α (PPARA). Blood concentrations of glucose, nonesterified fatty acids, and β-hydroxybutyrate were also determined. Liver biopsies and blood samples were taken at d 15 prepartum and at d 6, 21, 36, 51, and 66 postpartum from Holsteins (n = 6) and F1 Holstein-Gir (n = 6) cows. Cows were kept under the same prepartum and postpartum management conditions. The results showed that the expression of G6PC, PEPCK-C, BDH2, ACC, CPT2, HMGCR, SLC2A2, and PPARA genes did not differ between genetic groups. Except for PEPCK-C, no interaction between genetic groups and the experimental period was observed. Within both groups of cows, G6PC and PEPCK-C gene expression decreased when comparing prepartum gene expression with 21 and 36 DIM, and increased in d 51 postpartum. MUT mRNA levels differed between the 2 genetic groups and displayed a significant increase after d 36 postpartum, whereas mRNA levels of HMGCR tended to increase when comparing d 21 and 36 to d 51 postpartum. Glucose concentrations also differed between genetic groups, being significantly higher in the plasma of F1 Holstein-Gir cows than in Holstein cows, but no differences were found within each group during the analysis period. β-Hydroxybutyrate and nonesterified fatty acid concentrations did not differ between genetic groups, but displayed increased levels from prepartum to d 6 and 21 postpartum. Our results indicated that expression in the liver of genes involved with glucose and fatty acid metabolism were similar in both groups of cows and significant differences were observed between the 2 groups in the expression of MUT, a gene involved in propionate metabolism.

Differential proteomic profiling of endometrium and plasma indicate the importance of hydrolysis in bovine endometritis

Endometritis is an important disease of dairy cows that leads to significant economic losses in the dairy cattle industry. To investigate the alteration of proteins associated with endometritis in the dairy cow, the isobaric tags for relative and absolute quantification (iTRAQ) technique was applied to quantitatively identify differentially expressed proteins (DEP) in the endometrium and peripheral plasma of Chinese Holstein cows with endometritis. Compared with the normal (control) group, 159 DEP in the endometrium and 137 DEP in the plasma were identified in cows with endometritis. Gene ontology analysis demonstrated that the predominant endometrial DEP were primarily involved in responses to stimulus and stress processes and mainly played a role in hydrolysis in the extracellular region. The predominant plasma DEP were mainly components of the cytosol and non-membrane-bound organelles, and they were involved in the response to stress and regulation of enzyme activity. Protein-protein interaction of tissue DEP revealed that some core seed proteins, such as RAC2, ITGB2, and CDH1 in the same network as CD14, MMP3, and MMP9, had important functions in the cross-talk of pathways related to extracellular proteolysis. In summary, significant enzymatic hydrolase activity in the extracellular region is proposed as a molecular mechanism by which altered proteins may promote inflammation and hence endometritis.

Effect of exosomes from plasma of dairy cows with or without an infected uterus on prostaglandin production by endometrial cell lines

A contributing factor to declining fertility in dairy cows is an activated inflammatory system associated with uterine infection. Detecting uterine disease using biomarkers may allow earlier diagnosis and intervention with resultant improvements in fertility. Exosomes are known to participate in intercellular communication, paracrine, and endocrine signaling. Exosomes carry a cargo of proteins, lipids, and nucleic acids that represent specific cellular sources. Prostaglandins are lipids that are critical determinants of bovine fertility. In this study exosomes were isolated from the plasma of cows before (d 0) and during (d 10) the study in healthy animals or those with an induced uterine infection in a 2 × 2 factorial design. Exosomes were characterized for size and number (nanoparticle tracking analysis), exosomal marker expression (Western blot), and morphology (transmission electron microscopy). No significant differences were observed in exosome size or number. The abundance of exosome-enriched markers was confirmed in noninfected and infected animals. Transmission electron microscopy confirmed the morphology of the exosomes. These exosomes were co-incubated with bovine endometrial epithelial and stromal cells. Exosomes from d-10-infected animal plasma decreased PGF2α production in endometrial epithelial but not stromal cells. For future research, the identification of effectors in the cargo may provide a useful basis for early diagnosis of uterine infection using an exosomal characterization approach.

Critical thresholds of Ion Concentration in Plasma for Hypocalcemia prediction in dairy cows using receiver operating characteristic (ROC) analysis

Postpartum hypocalcemia is an important nutrient metabolic disease which occurs frequently in dairy cows. Parameters for early risk prediction of hypocalcemia have not been investigated previously in dairy cows on farms in China. To predict the occurrence of hypocalcemia and obtain the critical thresholds of various parameters related to the prevalence and risk of hypocalcemia in dairy cows. 61 Holstein Friesian cows from one farm were randomly selected and monitored using a plasma calcium(Ca) concentration of 2.0 mmol/L as the cutoff point of hypocalcemia. The risk prediction thresholds for hypocalcemia were determined by receiver operating characteristic (ROC) analysis using prenatal plasma Ca concentration and other electrolyte concentrations. The results showed that the plasma thresholds were more than 2.12 mmol/L for Ca before calving, with 98.7% sensitivity and 88.5% specificity, and more than 1.90 mmol/L for phosphorus (P), with 98.7% sensitivity and 65.4% specificity, respectively. Furthermore, there was a prominent positive correlation between the plasma concentration of Ca and that of P or magnesium (Mg) before calving in dairy cows. Levels of Ca and P in the plasma of dairy cows before calving are useful parameters for risk prediction of postpartum hypocalcemia incidents in dairy cows.

Temporal changes in sphingolipids and systemic insulin sensitivity during the transition from gestation to lactation.

Reduced insulin action develops naturally during the peripartum to ensure maternal nutrient delivery to the fetus and neonate. However, increased insulin resistance can facilitate excessive lipolysis which in turn promotes metabolic disease in overweight dairy cattle. Increased fatty acid availability favors the accumulation of the sphingolipid ceramide and is implicated in the pathogenesis of insulin resistance, however, the relationship between sphingolipid metabolism and insulin resistance during the peripartum remains largely unknown. Our objectives were to characterize temporal responses in plasma and tissue sphingolipids in lean and overweight peripartal cows and to establish the relationships between sphingolipid supply and lipolysis, hepatic lipid deposition, and systemic insulin action. Twenty-one multiparous lean and overweight Holstein cows were enrolled in a longitudinal study spanning the transition from gestation to lactation (d -21 to 21, relative to parturition). Plasma, liver, and skeletal muscle samples were obtained, and sphingolipids were profiled using LC/MS/MS. Insulin sensitivity was assessed utilizing intravenous insulin and glucose challenges. Our results demonstrated the following: first, insulin resistance develops postpartum concurrently with increased lipolysis and hepatic lipid accumulation; second, ceramides and glycosylated ceramides accumulate during the transition from gestation to lactation and are further elevated in overweight cows; third, ceramide accrual is associated with lipolysis and liver lipid accumulation, and C16:0- and C24:0-ceramide are inversely associated with systemic insulin sensitivity postpartum; fourth, plasma sphingomyelin, a potential source of ceramides reaches a nadir at parturition and is closely associated with feed intake; fifth, select sphingomyelins are lower in the plasma of overweight cows during the peripartal period. Our results demonstrate that dynamic changes occur in peripartal sphingolipids that are influenced by adiposity, and are associated with the onset of peripartal insulin resistance. These observations are in agreement with a putative potential role for sphingolipids in facilitating the physiological adaptations of peripartum.

Plasma amino acids and metabolic profiling of dairy cows in response to a bolus duodenal infusion of leucine.

Leucine (Leu), one of the three branch chain amino acids, acts as a signaling molecule in the regulation of overall amino acid (AA) and protein metabolism. Leucine is also considered to be a potent stimulus for the secretion of insulin from pancreatice β-cells. Our objective was to study the effects of a duodenal bolus infusion of Leu on insulin and glucagon secretion, on plasma AA concentrations, and to do a metabolomic profiling of dairy cows as compared to infusions with either glucose or saline. Six duodenum-fistulated Holstein cows were studied in a replicated 3 × 3 Latin square design with 3 periods of 7 days, in which the treatments were applied at the end of each period. The treatments were duodenal bolus infusions of Leu (DIL; 0.15 g/kg body weight), glucose (DIG; at Leu equimolar dosage) or saline (SAL). On the day of infusion, the treatments were duodenally infused after 5 h of fasting. Blood samples were collected at -15, 0, 10, 20, 30, 40, 50, 60, 75, 90, 120, 180, 210, 240 and 300 min relative to the start of infusion. Blood plasma was assayed for concentrations of insulin, glucagon, glucose and AA. The metabolome was also characterized in selected plasma samples (i.e. from 0, 50, and 120 min relative to the infusion). Body weight, feed intake, milk yield and milk composition were recorded throughout the experiment. The Leu infusion resulted in significant increases of Leu in plasma reaching 20 and 15-fold greater values than that in DIG and SAL, respectively. The elevation of plasma Leu concentrations after the infusion led to a significant decrease (P<0.05) in the plasma concentrations of isoleucine, valine, glycine, and alanine. In addition, the mean concentrations of lysine, methionine, phenylalanine, proline, serine, taurine, threonine, and asparagine across all time-points in plasma of DIL cows were reduced (P<0.05) compared with the other groups. In contrast to the working hypothesis about an insulinotropic effect of Leu, the circulating concentrations of insulin were not affected by Leu. In DIG, insulin and glucose concentrations peaked at 30–40 and 40–50 min after the infusion, respectively. Insulin concentrations were greater (P<0.05) from 30–40 min in DIG than DIL and SAL, and glucose was elevated in DIG over DIL and SAL from 30–75 min and 40–50 min, respectively. Multivariate metabolomics data analysis (principal component analysis and partial least squares discriminant analysis) revealed a clear separation when the DIL cows were compared with the DIG and SAL cows at 50 and 120 min after the infusion. By using this analysis, several metabolites, mainly acylcarnitines, methionine sulfoxide and components from the kynurenine pathway were identified as the most relevant for separating the treatment groups. These results suggest that Leu regulates the plasma concentrations of branched-chain AA, and other AA, apparently by stimulating their influx into the cells from the circulation. A single-dose duodenal infusion of Leu did not elicit an apparent insulin response, but affected multiple intermediary metabolic pathways including AA and energy metabolism by mechanisms yet to be elucidated.

Plasma and milk fatty acid composition as a response to dietary n-3 fatty acids and selenium in periparturient Holstein cows

Linseed is well known for abundant content of α- linolenic acid why it has been widely used as a source of n-3 fatty acid. Higher ratio of polyunsaturated fatty acids can increase lipid peroxidation. Selenium (Se) plays a key role in antioxidant enzymes and can therefore be regarded for use in attempts focused on protection of fatty acids from oxidation. The organic Se has been shown to have higher bioavailability compared to the inorganic selenium. The aim of this research was to determine the influence of dietary replacement of n-6 with n-3 polyunsaturated fatty acids on plasma and milk fatty acid composition in the dairy cows. The experiment was conducted on 30 dairy Holstein cows in the period from parturition until the 3rd week of lactation. Soybean meal from control (C) group was replaced with grounded linseed in the both experimental (LS and LS+Se) groups. In addition to that, in the 2nd experimental (LS+Se) group sodium selenite from premix was replaced with organic selenium. Blood and milk samples were collected at 21st day of lactation and fatty acids were determined using gas chromatography from it. Feeding dairy cows during transition period with linseed showed a positive impact on milk fatty acid composition by increasing (P 0.05).

Oxidative status of dairy cows fed flax meal and infused with sunflower oil in the abomasum

Flax products increase concentration of antioxidants in milk and plasma of dairy cows, which may reduce oxidative damage resulting from lipoperoxidation of polyunsaturated fatty acids. The aim of this study was to investigate the effects of flax meal on the antioxidant status of dairy cows infused with sunflower oil (SO), a source of omega-6 fatty acids (FA), in the abomasum. Eight rumen fistulated lactating Holstein cows were assigned to a double 4×4 Latin square design with a 2×2 factorial arrangement of treatments: (1) control diet with no flax meal and no infusion of SO (CO); (2) diet containing 137g/kg flax meal (FM); (3) CO and infusion of 250g SO/d; and (4) FM and infusion of 250g SO/d. Dry matter intake and milk production were similar among diets. Flax meal increased milk fat concentration. Dietary FM supplementation increased plasma concentration of saturated fatty acids, and tended to reduce the polyunsaturated to saturated FA ratio. The plasma peroxidizability index was not affected by FM supplementation or SO infusion. Infusion of SO increased antioxidant capacity and rate of diene production, and decreased the time to reach maximal amount of conjugated diene production in plasma. Production of thiobarbituric reactive substances (TBARS) in ruminal fluid was reduced by dietary FM. Milk and plasma TBARS production were not affected by FM supplementation. Sunflower oil had no effect on TBARS production in ruminal contents, milk and plasma. In conclusion, feeding FM to dairy cows receiving a source of omega-6 FA (250g/d) that bypasses the rumen did not protect cows and milk from lipoperoxidation.

Analysis of hepatic transcript profile and plasma lipid profile in early lactating dairy cows fed grape seed and grape marc meal extract

BackgroundIt was recently reported that dairy cows fed a polyphenol-rich grape seed and grape marc meal extract (GSGME) during the transition period had an increased milk yield, but the underlying reasons remained unclear. As polyphenols exert a broad spectrum of metabolic effects, we hypothesized that feeding of GSGME influences metabolic pathways in the liver which could account for the positive effects of GSGME in dairy cows. In order to identify these pathways, we performed genome-wide transcript profiling in the liver and lipid profiling in plasma of dairy cows fed GSGME during the transition period at 1 week postpartum.ResultsTranscriptomic analysis of the liver revealed 207 differentially expressed transcripts, from which 156 were up- and 51 were down-regulated, between cows fed GSGME and control cows. Gene set enrichment analysis of the 155 up-regulated mRNAs showed that the most enriched gene ontology (GO) biological process terms were dealing with cell cycle regulation and the most enriched Kyoto Encyclopedia of Genes and Genomes pathways were p53 signaling and cell cycle. Functional analysis of the 43 down-regulated mRNAs revealed that a great part of these genes are involved in endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) and inflammatory processes. Accordingly, protein folding, response to unfolded protein, unfolded protein binding, chemokine activity and heat shock protein binding were identified as one of the most enriched GO biological process and molecular function terms assigned to the down-regulated genes. In line with the transcriptomics data the plasma concentrations of the acute phase proteins serum amyloid A (SAA) and haptoglobin were reduced in cows fed GSGME compared to control cows. Lipidomic analysis of plasma revealed no differences in the concentrations of individual species of major and minor lipid classes between cows fed GSGME and control cows.ConclusionsAnalysis of hepatic transcript profile in cows fed GSGME during the transition period at 1 week postpartum indicates that polyphenol-rich feed components are able to inhibit ER stress-induced UPR and inflammatory processes, both of which are considered to contribute to liver-associated diseases and to impair milk performance in dairy cows, in the liver of dairy cows during early lactation.

Effects of female bovine plasma collected at different days of the estrous cycle on epididymal spermatozoa motility

The aim of this study was to assess the effects of female bovine plasma collected at different days of the reproductive cycle on epididymal spermatozoa motility and to test hypothesis that the subpopulations pattern of motile spermatozoa is affected by this treatment. Blood plasma samples were collected from five Holstein Friesian cows at different stages of the estrous cycle (days 0, 5, 10, 12 and 18), one pregnant cow and one adult bull and were diluted 1:9 (V/V) with normal saline. Female charcoal-treated plasma, Bull plasma and saline were used as controls. Semen samples were obtained from cauda epididymidis through retrograde flushing and diluted in saline to approximately 60 × 106 sperm/ml. The extended semen was diluted 1:2 (V/V) with tested media and motility was evaluated at 15 min and then every hour for 6 h using a computer-assisted semen analysis. Multivariate clustering procedure was applied to identify and quantify specific subpopulations within the semen samples. The statistical analysis clustered all the motile spermatozoa into three separate subpopulations with defined patterns of movement: Subpopulation 1 poorly motile and non-progressive spermatozoa (39.3%), subpopulation 2 including the fastest and the most vigorous spermatozoa (46.4%) and subpopulation 3 represented by slow, non-vigorous but linear spermatozoa (14.3%). Initially, sperm samples supplemented with female, male or female charcoal-treated plasma stimulated equally total motility and spermatozoa belonging to subpopulation 2 regardless of the estrous cycle stage. After 1-h incubation, the motility of these both categories of spermatozoa (total motile and those assigned to subpopulation 2) is enhanced and maintained more in day 12, 18 and pregnant cow plasma than in female plasma from earlier stage of the estrous cycle (day 0, 5 and 10), male plasma and female-charcoal treated plasma. In conclusion, the overall results showed that female plasma stimulated significantly sperm motility, especially at the late stage of the estrous cycle. Additionally, to the diverse compounds contained in blood plasma, progesterone may play a key role in such motility activation.

β-glucuronidase activity and enterolactone concentration in ruminal fluid, plasma, urine, and milk of Holstein cows fed increased levels of flax (Linum usitatissimum) meal

The main mammalian lignan present in milk of dairy cows fed flax products is enterolactone (EL), but the relationship between EL concentration in milk and body fluids when cows are fed increased proportions of flax meal (FM) is unknown. The objectives were to investigate the effects of increased levels of FM on EL concentration in milk, plasma, urine, and ruminal fluid and the activity of β-glucuronidase in ruminal fluid and feces. Eight rumen-cannulated cows were assigned to a double 4×4 Latin square design with four 21 d periods and four diets: control diet with no FM (CON) or a diet with 50, 100 and 150g/kg of FM. Concentrations of EL in urine, ruminal fluid, milk, and plasma increased linearly with FM supplementation. Spearman’s correlation coefficients were significant for all comparisons except that only a trend was observed between concentration of EL in urine and that in ruminal fluid before feeding. The strongest correlation was observed between EL concentration in ruminal fluid post-feeding and that in milk. Feeding increased proportions of FM in the diet had no effect on β-glucuronidase activity. Unlike to what is observed in non-ruminant animals, present results suggest that the activity of β-glucuronidase in the rumen is of little importance for the absorption of EL and its transfer in milk and other physiological fluids. Further studies are required to better understand and improve EL production and absorption, which could contribute to enhance animal health and the transfer of antioxidant components in milk.

Palmitic acid feeding increases ceramide supply in association with increased milk yield, circulating nonesterified fatty acids, and adipose tissue responsiveness to a glucose challenge.

Reduced insulin action is a key adaptation that facilitates glucose partitioning to the mammary gland for milk synthesis and enhances adipose tissue lipolysis during early lactation. The progressive recovery of insulin sensitivity as cows advance toward late lactation is accompanied by reductions in circulating nonesterified fatty acids (NEFA) and milk yield. Because palmitic acid can promote insulin resistance in monogastrics through sphingolipid ceramide-dependent mechanisms, palmitic acid (C16:0) feeding may enhance milk production by restoring homeorhetic responses. We hypothesized that feeding C16:0 to mid-lactation cows would enhance ceramide supply and ceramide would be positively associated with milk yield. Twenty multiparous mid-lactation Holstein cows were enrolled in a study consisting of a 5-d covariate, 49-d treatment, and 14-d posttreatment period. All cows were randomly assigned to a sorghum silage-based diet containing no supplemental fat (control; n=10; 138±45 d in milk) or C16:0 at 4% of ration dry matter (PALM; 98% C16:0; n=10; 136±44 d in milk). Blood and milk were collected at routine intervals. Liver and skeletal muscle tissue were biopsied at d 47 of treatment. Intravenous glucose tolerance tests (300mg/kg of body weight) were performed at d -1, 24, and 49 relative to start of treatment. The plasma and tissue concentrations of ceramide and glycosylated ceramide were determined using liquid chromatography coupled with tandem mass spectrometry. Data were analyzed as repeated measures using a mixed model with fixed effects of treatment and time, and milk yield served as a covariate. The PALM treatment increased milk yield, energy-corrected milk, and milk fat yield. The most abundant plasma and tissue sphingolipids detected were C24:0-ceramide, C24:0-monohexosylceramide (GlcCer), and C16:0-lactosylceramide. Plasma concentrations of total ceramide and GlcCer decreased as lactation advanced, and ceramide and GlcCer were elevated in cows fed PALM. Palmitic acid feeding increased hepatic ceramide levels, a response not observed in skeletal muscle tissue. Plasma ceramides (e.g., C24:0-ceramide) were positively correlated with plasma NEFA and milk yield, and positively correlated with NEFA levels following a glucose challenge. Our data demonstrate a remodeled plasma and hepatic sphingolipidome in mid-lactation dairy cows fed PALM. The potential involvement in ceramide in homeorhetic nutrient partitioning to support lactation requires further consideration.

Effects of nutritional status on hormone concentrations of the somatotropin axis and metabolites in plasma and colostrum of Japanese Black cows.

We aimed to determine the effects of nutritional status on concentrations of somatotropic axis hormones (growth hormone (GH) and insulin-like growth factor 1 (IGF-1)), insulin and metabolites (glucose, total protein and nonesterified fatty acids (NEFA)) in the plasma and colostrum in late antepartum cows. Eight pregnant Japanese Black cows were randomly assigned to two experimental groups (n = 4 per group). Control cows (CON) received 100% of their nutritional requirements until parturition, whereas restricted group cows (RES) received 60% of their nutritional requirements. Blood samples were taken during the antepartum period, and blood and colostrum samples were collected on days 0, 1, and 3 after calving. Compared to the CON group, the RES group had higher concentrations of GH and NEFA in plasma, but significantly lower concentrations of glucose and insulin in plasma. The concentrations of GH in plasma after calving were significantly higher, but total plasma protein was significantly lower in RES than in CON cows. Compared to the CON group, the RES group had significantly higher concentrations of GH in colostrum, but significantly lower total concentrations of protein in colostrum. Concentrations of IGF-1 were not different between the two groups. These findings suggest that maternal nutritional status during late gestation influences concentrations of GH and total protein in the blood and colostrum of Japanese Black cows.

The effects of late gestation maternal nutrient restriction with or without protein supplementation on endocrine regulation of newborn and postnatal beef calves

A study was conducted to evaluate late gestation maternal nutrient restriction (NR) with or without protein supplementation on endocrine regulation in newborn beef calves. This study used multiparous cows (4 and 5 years of age, n = 57) randomly assigned to one of three treatments for the last 100 days of gestation. The control (Con; n = 19) cows were fed to increase body condition score, whereas the NR (n = 19) and NR with protein supplement (NRS, n = 19) cows were fed to lose 1.2 ± 0.2 body condition score units during the last 100 days of gestation. Control cows were allowed ad libitum access to tall fescue/crabgrass paddock and, when grazing became insufficient, ad libitum hay was provided along with 1.3 kg of corn gluten feed 5 days/wk. Tall fescue paddocks were strip grazed to limit forage availability for NR and NRS. The NRS-treated dams were individually penned and fed 0.45 kg of soybean meal 3 days/wk. As forage became limited, the nutrient-restricted paddocks received limited fescue hay. After parturition cow/calf pairs were moved to a common pasture and received ad libitum silage and high-concentrate feed. Maternal NR regardless of supplementation reduced cow plasma glucose and insulin concentrations during late gestation (P < 0.0001 and P = 0.0051, respectively). Calves from NR dams weighed less at birth than Con calves (P = 0.04), whereas NRS calves were intermediate (33.4 ± 1.2, 35.0 ± 1.3, and 37.2 ± 1.3 kg NR, NRS, and Con, respectively). Plasma glucose concentrations of unsuckled calves at birth were reduced (P = 0.037) in NR and NRS calves compared with Con (67.7 ± 6.5 and 60.1 ± 6.9 vs. 83.7 ± 6.1 mg/dL, respectively). At birth, Con and NRS calves had increased (P = 0.0037) plasma leptin concentrations compared with NR calves, whereas calf plasma cortisol concentrations were greater for the nutrient-restricted groups than the Con group (treatment × day P = 0.0135). Plasma IgG concentrations from calves at 5 days of age were similar (P = 0.701) between maternal late gestation treatments. This research reports that late gestation NR reduces postnatal calf birth weight, plasma glucose and leads to reduced plasma leptin. Maternal protein supplementation appears to partially alleviate the effects of late gestation NR on reducing plasma leptin, birth weight, and growth rate from Day 30 of age to weaning.

Natural autoantibodies in Bos taurus calves during the first twelve weeks of life

Natural autoantibodies (NAAb) have a role in maintaining physiological homeostasis and prevention of infections, and have been found in mammalian species tested so far. Albeit NAAb levels rise with age, little is known about the origin, function, regulation and initiation of NAAb in young animals. The present study addressed the presence of IgM and IgG NAAb binding glutamate dehydrogenase (GD), carbonic anhydrase (CA), myosin (MYO) and transferrin (TRANS) from before drinking colostrum until the first 12 weeks of life in plasma of female calves. In addition, NAAb to these four self-antigens were also measured in colostrum and in plasma of their mothers during three weeks before calving. Titers of NAAb binding GD, CA, MYO and TRANS were detected in plasma of cows before calving, in colostrum, and in plasma of calves before and after drinking of colostrum. Levels of NAAb in colostrum were positively related with levels of NAAb in plasma of cows. Before colostrum intake, levels of NAAb in plasma of calves were not related with levels of NAAb in plasma of their mother but were influenced by parity of their mother. After colostrum intake, levels of NAAb in plasma of calves in the first week of life were positively related with levels of NAAb in colostrum. Low NAAb levels in colostrum were related with low NAAb in plasma of calves in the first week of life, but after two weeks of life the relation between colostrum and plasma of calves was absent. In conclusion, NAAb are already present in the unborn calf, and levels of neonatal NAAb during the early weeks of life are affected by levels of maternal NAAb obtained via colostrum.