Periparturient Period In Dairy Cows Research Articles

Periparturient blood T-lymphocyte PD-1 and CTLA-4 expression as potential predictors of new intramammary infections in dairy cows during early lactation (short communication)

BackgroundThe periparturient period in dairy cows is marked by immunosuppression which increases the likelihood of infectious disorders, particularly also mastitis. An in-depth understanding of peripartum leukocyte biology is vital for the implementation of highly successful post-partum disease prevention measures. Immune checkpoint molecules, such as programmed death 1 (PD-1) and cytotoxic T-lymphocyte antigen 4 (CTLA-4), are critical inhibitory receptors expressed on immune cells, particularly T cells, that drive immunosuppressive signaling pathways. However, the potential role of immune checkpoint molecules expression in T-cells on udder health has never been explored. Thus, the association between the occurrence of new postpartum intramammary infections (IMIs) and the expression of programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) on blood T-cells during the peripartum period was investigated.ResultsIn this study, the incidence of IMIs by any pathogen in early lactation was not associated with a higher expression of PD-1 and CTLA-4 in the periparturient period. However, the incidence of IMIs by major pathogens throughout the first month of lactation was significantly associated with higher expression of PD-1 at 14 days before calving (P = 0.03) and CTLA-4 at parturition (P = 0.03) by blood T-cells. Also, the expression of CTLA-4 at D0 (P = 0.012) by T-cells was associated with the occurrence of persistent IMIs during the first month of lactation.ConclusionsTo our knowledge, this is the first report to investigate the expression of PD-1 and CTLA-4 by blood T-lymphocytes during the periparturient period in dairy cows and to explore their relationship with the incidence of new IMIs in the postpartum period. Thus, a comprehensive understanding of leukocyte biology during peripartum would appear to be a prerequisite for the identification of resilient dairy cows or targets innovative (immunological) non-antibiotic approaches in the transition period.

Haemato-biochemical changes associated with peri-parturient period in dairy cows

Haemato-biochemical changes associated with peri-parturient period in dairy cows

Meta-analysis of the effects of dietary sources of selenium on lactational performance and oxidative status of dairy cows

Selenium is an essential trace element to maintain normal physiological and immunological systems. The role of various types and forms of Se on the productive performance and antioxidant status of dairy cows is overwhelming in the existing empirical evidence and, therefore, needs to be quantitatively summarized. This meta-analysis evaluated the effects of different types and forms of Se intake on the productive and oxidative status of various physiological stages of dairy cows. A database was built from 29 peer-reviewed publications that reported lactation performance, Se concentrations in the blood or milk, or antioxidant parameters of dairy cows. A total of 139 observations were included in the analysis according to mixed model univariate and multivariate regression analyses by evaluating the Se levels (%), intake (mg/d), Se forms (organic vs inorganic), Se types (Se-selenite, Se-yeast, Se-methionine) and other categorical predictors in the models. Then, the models were evaluated and cross-validated to select the best-fitted models on some important parameters. Se intake, in any form and type, had no relationship with milk yield but was positively associated with fat-corrected milk (FCM) yield due to a trend of linear increase in milk fat yield (g/d). A significant interaction of Se intake × lactation phase was observed. Daily Se intake positively affected the dry matter intake (DMI) of periparturient cows but did not affect the DMI of lactation cows. Increasing Se intake resulted in a linear increase of DMI and moderately increased glutathione peroxidase (GSH-Px) during the periparturient period but had no significant effect during early and mid-lactation of dairy cows. The interaction model of Se intake × Se forms was the best predictor to evaluate Se concentration in blood and milk. The organic Se had a higher transfer rate from diets to blood without a statistical difference between Se-yeast and Se-methionine. In milk, intake of Se-methionine demonstrated a strong linear increase in Se concentration and had a 47% higher slope of transfer rate than Se-yeast (2.47 µg/kg and R2 = 0.91 vs 1.68 µg/kg and R2 = 0.48, respectively). The amount of daily Se intake also curvilinearly affected superoxide dismutase activity and malondialdehyde concentration. Altogether, the predicted models and results of the present meta-analysis provide empirical evidence that organic Se, especially Se-methionine, had a higher transfer rate from diets into the milk than organic Se-yeast. Organic Se might also improve milk protein and fat-corrected milk in lactating cows and antioxidant status in the periparturient period of dairy cows.

Resveratrol reverses Palmitic Acid-induced cow neutrophils apoptosis through shifting glucose metabolism into lipid metabolism via Cav-1/ CPT 1-mediated FAO enhancement

Elevated plasma nonesterified fatty acids (NEFAs) affect neutrophils function and longevity during the periparturient period in dairy cows. Previous research has shown that resveratrol (RSV) may protect cell viability from NEFA-induced damage by regulating energy metabolism. However, it is unclear whether RSV has a protective effect on palmitic acid (PA)-treated neutrophils. The aim of this study was to investigate the molecular regulatory mechanism of the protective effect of RSV on neutrophils. The results showed that treatment with high concentrations of RSV (50 μM, 100 μM) maintained neutrophils activity by inhibiting neutrophils apoptosis (P < 0.05). Further analysis showed that high concentrations of RSV enhanced fatty acid oxidation (FAO) to produce ATP by promoting the expression of CAV1, ACSL-1 and CPT1 (P < 0. 05) while inhibiting glycolysis by suppressing PFK1 activity (P < 0. 05) and reducing glucose transport-related protein (GLUT1/GLUT4) expression by inhibiting glucose uptake (P < 0.05). These results suggest that RSV protects neutrophils from PA-induced apoptosis by regulating energy metabolism. Our results revealed that RSV protects neutrophils from PA-induced apoptosis by shifting glucose metabolism to lipid metabolism. This study tenders to a meaningful understanding of the effects of RSV on neutrophils function in periparturient cows suffering from negative energy balance (NEB).

Alterations in skeletal muscle abundance of protein turnover, stress, and antioxidant proteins during the periparturient period in dairy cows fed ethyl-cellulose rumen-protected methionine

Skeletal muscle turnover helps support the physiological needs of dairy cows during the transition into lactation. We evaluated effects of feeding ethyl-cellulose rumen-protected methionine (RPM) during the periparturient period on abundance of proteins associated with transport AA and glucose, protein turnover, metabolism, and antioxidant pathways in skeletal muscle. Sixty multiparous Holstein cows were used in a block design and assigned to a control or RPM diet from -28 to 60 d in milk. The RPM was fed at a rate of 0.09% or 0.10% of dry matter intake (DMI) during the prepartal and postpartal periods to achieve a target Lys:Met ratio in the metabolizable protein of ∼2.8:1. Muscle biopsies from the hind leg of 10 clinically healthy cows per diet collected at -21, 1, and 21 d relative to calving were used for western blotting of 38 target proteins. Statistical analysis was performed using the PROC MIXED statement of SAS version 9.4 (SAS Institute Inc.) with cow as random effect, whereas diet, time, and diet × time were the fixed effects. Diet × time tended to affect prepartum DMI, with RPM cows consuming 15.2 kg/d and controls 14.6 kg/d. However, diet had no effect on postpartum DMI (17.2 and 17.1 ± 0.4 kg/d for control and RPM, respectively). Milk yield during the first 30 d in milk was also not affected by diet (38.1 and 37.5 ± 1.9 kg/d for control and RPM, respectively). Diet or time did not affect the abundance of several AA transporters or the insulin-induced glucose transporter (SLC2A4). Among evaluated proteins, feeding RPM led to lower overall abundance of proteins associated with protein synthesis (phosphorylated EEF2, phosphorylated RPS6KB1), mTOR activation (RRAGA), proteasome degradation (UBA1), cellular stress responses (HSP70, phosphorylated MAPK3, phosphorylated EIF2A, ERK1/2), antioxidant response (GPX3), and de novo synthesis of phospholipids (PEMT). Regardless of diet, there was an increase in the abundance of the active form of the master regulator of protein synthesis phosphorylated MTOR and the growth-factor-induced serine/threonine kinase phosphorylated AKT1 and PIK3C3, whereas the abundance of a negative regulator of translation (phosphorylated EEF2K) decreased over time. Compared with d 1 after calving and regardless of diet, the abundance of proteins associated with endoplasmic reticulum stress (XBP1 spliced), cell growth and survival (phosphorylated MAPK3), inflammation (transcription factor p65), antioxidant responses (KEAP1), and circadian regulation (CLOCK, PER2) of oxidative metabolism was upregulated at d 21 relative to parturition. These responses coupled with the upregulation of transporters for Lys, Arg, and His (SLC7A1) and glutamate/aspartate (SLC1A3) over time were suggestive of dynamic adaptations in cellular functions. Overall, management approaches that could take advantage of this physiological plasticity may help cows make a smoother transition into lactation.

Cannabinoid-1 receptor activation modulates lipid mobilization and adipogenesis in the adipose tissue of dairy cows

Amplified adipose tissue (AT) lipolysis and suppressed lipogenesis characterize the periparturient period of dairy cows. The intensity of lipolysis recedes with the progression of lactation; however, when lipolysis is excessive and prolonged, disease risk is exacerbated and productivity compromised. Interventions that minimize lipolysis while maintaining adequate supply of energy and enhancing lipogenesis may improve periparturient cows' health and lactation performance. Cannabinoid-1 receptor (CB1R) activation in rodent AT enhances the lipogenic and adipogenic capacity of adipocytes, yet the effects in dairy cow AT remain unknown. Using a synthetic CB1R agonist and an antagonist, we determined the effects of CB1R stimulation on lipolysis, lipogenesis, and adipogenesis in the AT of dairy cows. Adipose tissue explants were collected from healthy, nonlactating and nongestating (NLNG; n = 6) or periparturient (n = 12) cows at 1 wk before parturition and at 2 and 3 wk postpartum (PP1 and PP2, respectively). Explants were treated with the β-adrenergic agonist isoproterenol (1 μM) in the presence of the CB1R agonist arachidonyl-2'-chloroethylamide (ACEA) ± the CB1R antagonist rimonabant (RIM). Lipolysis was quantified based on glycerol release. We found that ACEA reduced lipolysis in NLNG cows; however, it did not exhibit a direct effect on AT lipolysis in periparturient cows. Inhibition of CB1R with RIM in postpartum cow AT did not alter lipolysis. To evaluate adipogenesis and lipogenesis, preadipocytes isolated from NLNG cows' AT were induced to differentiate in the presence or absence of ACEA ± RIM for 4 and 12 d. Live cell imaging, lipid accumulation, and expressions of key adipogenic and lipogenic markers were assessed. Preadipocytes treated with ACEA had higher adipogenesis, whereas ACEA+RIM reduced it. Adipocytes treated with ACEA and RIM for 12 d exhibited enhanced lipogenesis compared with untreated cells (control). Lipid content was reduced in ACEA+RIM but not with RIM alone. Collectively, our results support that lipolysis may be reduced by CB1R stimulation in NLNG cows but not in periparturient cows. In addition, our findings demonstrate that adipogenesis and lipogenesis are enhanced by activation of CB1R in the AT of NLNG dairy cows. In summary, we provide initial evidence which supports that the sensitivity of the AT endocannabinoid system to endocannabinoids, and its ability to modulate AT lipolysis, adipogenesis, and lipogenesis, vary based on dairy cows' lactation stage.

Alterations in Skeletal Muscle mRNA Abundance in Response to Ethyl-Cellulose Rumen-Protected Methionine during the Periparturient Period in Dairy Cows.

Simple SummaryImprovements in performance around parturition by feeding ethyl-cellulose rumen-protected methionine (RPM) have been reported. Hepatic and adipose gene transcription effects have been a key focus of studies dealing with RPM. It is unknown, however, if RPM alters the abundance of genes associated with nutrient metabolism and biochemical pathways in skeletal muscle. This tissue also experiences dynamic biological changes around parturition. The objective was to use skeletal muscle biopsies from cows fed a control or RPM-supplemented diet around parturition to investigate alterations in mRNA abundance. Compared with controls, feeding RPM led to overall upregulation of genes associated with amino acid transport, carnitine transport, β-oxidation, vitamin transport, mTOR pathway, insulin signaling, antioxidant response, CDP-Choline pathway, and arginine metabolism. Thus, besides positive effects at the level of performance, RPM can help skeletal muscle maintain homeostasis around parturition partly through alterations in mRNA abundance.This study aimed to evaluate the effect of feeding ethyl cellulose rumen-protected methionine (RPM) on skeletal muscle mRNA abundance during the periparturient period. Sixty multiparous Holstein cows were used in a block design and assigned to either a control or RPM diet. The RPM was supplied from −28 to 60 days in milk (DIM) at a rate of 0.09% (prepartum) or 0.10% (postpartum) of dry matter (DM), ensuring a Lys:Met in the metabolizable protein of ~2.8:1. Muscle biopsies were collected at −21, 1, and 21 DIM. Thirty-five target genes associated with nutrient metabolism and biochemical pathways were measured via RT-qPCR. The mRNA abundance of genes associated with amino acid (AA) transport (SLC7A8, SLC43A2), carnitine transport (SLC22A5), insulin signaling (IRS1), and antioxidant response (NFE2L2) had diet × time effect (p < 0.05) due to greater abundance in RPM versus CON cows, especially at 1 and 21 DIM. Members of the AA transport (SLC7A8, SLC25A29, SCL38A9), fatty acid β-oxidation (ACADVL), vitamin transport (SLC5A6, SLC19A2), mTOR pathway (AKT1 and mTOR), antioxidant response (KEAP1, CUL3), CDP-Choline pathway and arginine metabolism had overall greater abundance (p < 0.05) in RPM versus CON cows. Overall, data indicate that RPM can alter nutrient metabolism in the skeletal muscle around parturition partly through alterations in mRNA abundance.

Investigation of omentin-1 and metabolic parameters in periparturient cows

We aimed to determine the level of omentin-1 hormone and other in periparturient period of dairy cows. It was also aimed to determine whether there is a correlation between omentin-1, glucose, Non-esterified fatty acids (NEFA), triglycerides (TG) and β-hydroxybutyrate (BHB). Blood samples were taken a month before parturition (PreP30), two weeks before parturition (PreP14), at parturition (P), two weeks after parturition (PostP14) and a month after parturition (PostP30). Concentrations of serum omentin-1 at P, serum glucose at P, PostP14, and PostP30, serum NEFA at P, serum TG PreP30 and PreP14, and serum BHB at P were statistically significantly higher than at other times. A positive correlation was observed between omentin-1 and glucose, NEFA and BHB, glucose and NEFA and BHB, and NEFA and BHB. A negative correlation was found between TG and omentin-1, glucose, NEFA and BHB. In conclusion, findings of the present study shows that omentin-1 may play an important role in the periparturient period. A positive correlation of omentin-1 with energy fuels NEFA, glucose, and BHB suggests that omentin-1 plays a role in energy metabolism like other adipokines. The fact that omentin-1 levels increase during delivery, when the fetus needs energy most, supports this hypothesis.

Factors associated with negative energy balance in periparturient dairy cows raised under tropical climate of Thailand-A mini-review.

This review attempted to explain factors associated with negative energy balance (NEB) occurring during the periparturient period in dairy cows raised under tropical climatic conditions. The NEB has long been proven as an inevitable event in periparturient dairy cows. This condition had negative effects on the overall performances of dairy cows, including milk production, reproduction, and health condition. Therefore, periparturient management to overcome the NEB problem is vital for optimizing profit in dairy farming. In most tropical countries such as Thailand, dairy cows have been predominantly kept by small-holder farmers. Consequently, baseline milk yields, feed availability, feeding management, and general farming practices are different from typical commercial dairy farming. Heat stress also plays a crucial role in NEB conditions, and elevated temperature-humidity indexes above-normal conditions are recorded throughout the year. These factors influence the NEB in tropical dairy cows, which could result in different outcomes and consequences. Understanding the affecting components of NEB in dairy cows would help alleviate the severity of the NEB and its consequences, optimizing the dairy cow’s performance.

Significance of vitamin A and E during periparturient period in dairy cows and buffaloes-A review

Significance of vitamin A and E during periparturient period in dairy cows and buffaloes-A review

Technical note: Comparative evaluation of 3 methods for the quantification of nonesterified fatty acids in bovine plasma sampled prepartum

Serum or plasma concentrations of nonesterified fatty acids (NEFA) are commonly used as biomarkers of lipolysis during the periparturient period in dairy cows. However, NEFA quantification usually requires sample submission to specialized diagnostic laboratories, at significant cost. Alternative methods for the measurement of NEFA concentrations are needed that decrease the cost per sample without compromising accuracy and precision. Our study compared the quantification of NEFA between the gold standard diagnostic laboratory method and 2 alternative methods: a 96-well plate protocol and a small-scale chemistry analyzer (CataChemWell-T; Catachem Inc., Oxford, CT). We used a total of 147 plasma samples collected from cows 7 to 13 d before their expected calving date (7 ± 3.3; mean ± SD days before actual calving) were used. We used linear and Passing-Bablok regression to identify systematic and proportional bias between the alternative methods and the gold standard. We also examined the level of agreement between each alternative method and the gold standard using Bland-Altman plots. We calculated the sensitivity and specificity of the alternative methods for detecting animals with excessive lipid mobilization prepartum (defined as NEFA concentration ≥0.30 mM by the gold standard test). We identified a constant difference between each of the alternative NEFA determination methods and the gold standard. Nevertheless, the mean bias was relatively small (-0.03 mM and -0.02 mM for the 96-well plate and small-scale analyzer methods, respectively). However, this tendency to underestimate NEFA concentrations had only a minimal effect on the ability of the tests to detect cows with excessive lipid mobilization prepartum (specificity 100%; sensitivity 88.9 and 94.4% for the 96-well plate and small-scale analyzer methods, respectively). The 96-well plate and small-scale chemistry analyzer methods tested in this study are suitable for the quantification of NEFA concentrations in plasma and the dichotomous classification of samples as indicators of excessive prepartum lipid mobilization.

Hepatic Cystathionine β-Synthase Activity Is Increased by Greater Postruminal Supply of Met during the Periparturient Period in Dairy Cows

ABSTRACTBackgroundPostruminal supply of Met during the periparturient period enhances production efficiency (feed conversion to milk) in dairy cows partly through alleviation of oxidant and inflammatory status. Whether alterations in hepatic 1-carbon metabolism (major contributor of antioxidants) and/or energy metabolism contribute to these beneficial effects is unknown.ObjectivesTo investigate alterations in hepatic 1-carbon and energy metabolism and associations with plasma amino acids (AAs) and production efficiency in response to enhanced postruminal supply of Met.MethodsHolstein cows (n = 30 per group) were fed during the last 28 d of pregnancy a control diet (CON) or the control plus ethylcellulose rumen-protected Met (MET; 0.9 g/kg of dry matter intake). Plasma (n = 15 per group) and liver tissue (n = 10 per group) were collected throughout the periparturient period to evaluate AA profiles, activity of the tricarboxylic acid cycle, and 1-carbon metabolism via mRNA abundance, enzyme activity, and targeted metabolomics.ResultsCows in the MET group had greater overall (27%, P = 0.027) plasma Met concentrations, but had similar total plasma AA concentrations. Although mRNA abundance of 1-carbon metabolism enzymes did not differ, hepatic activity of cystathionine β-synthase (CBS) (51.2 compared with 44.4 mmol/h/mg protein; P = 0.032) and concentration (19%, P = 0.048) of the cellular antioxidant glutathione were greater overall in the MET group. mRNA abundance of aconitase 2 and fumarate hydratase was greater overall (P = 0.049), and phosphoenolpyruvate carboxykinase 1 tended (P = 0.093) to be greater overall in cows fed MET. There was a tendency (P ≤ 0.093) for greater overall hepatic concentrations of malic acid, α-ketoglutaric acid, and isocitric acid in cows fed MET.ConclusionsGreater activity of CBS in response to enhanced postruminal supply of Met likely contributes to alleviating oxidant status by increasing concentrations of glutathione. Hence, transsulfuration plays an important role in the observed improvements in production efficiency of dairy cows during the periparturient period.

Folic acid supplementation regulates key immunity-associated genes and pathways during the periparturient period in dairy cows.

ObjectiveThe current research was aimed to profile the transcriptomic picture of the peripheral blood lymphocytes (PBLs) associated with immunity in Chinese Holsteins supplemented orally with coated folic acid during the periparturient period.MethodsThe total of 123 perinatal cows were selected for this study and divided into three groups; group A (n = 41, 240 mg/500 kg cow/d), group B (n = 40, 120 mg/500 kg cow/d) and group C (n = 42, 0 mg/cow/d) based on the quantity of folic acid fed. Three samples of PBLs were selected from each folic acid treated group (high, low, and control) and RNA sequencing method was carried out for transcriptomic analysis.ResultsThe analysis revealed that a higher number of genes and pathways were regulated in response to high and low folic acid supplementation compared to the controls. We reported the novel pathways tumor necrosis factor (TNF) signaling, antigen processing and presentation, Staphylococcus aureus infection and nuclear factor (NF)-kappa B signaling pathways) and the key genes (e.g. C-X-C motif chemokine ligand 10, TNF receptor superfamily member 1A, cluster difference 4, major histocompatibility complex, class II, DQ beta, NF-kappa-B inhibitor alpha, and TNF superfamily 13) having great importance in immunity and anti-inflammation in the periparturient cows in response to coated folic acid treatment.ConclusionCollectively, our study profiled first-time transcriptomic analysis of bovine lymphocytes and compared the involved cytokines, genes, and pathways between high vs control and low vs control. Our data suggest that the low folic acid supplementation (120 mg/500 kg) could be a good choice to boost appropriate immunity and anti-inflammation as well as might being applied to the health improvement of perinatal dairy cows.

The association between metabolic profile indices, clinical parameters, and ultrasound measurement of backfat thickness during the periparturient period of dairy cows

This study aimed to evaluate clinical and biochemical changes in dairy cows during periparturient period. It was carried out on 38 multiparous Holstein/Fersian crossbreed dairy cows 3–11 years old. Using ultrasonography for measurement backfat thickness (BFT) for detection of the energy deficit. BFT on dairy cattle is used to monitor changes in subcutaneous fat thickness which represent changes in energy stores. On the basis of clinical examination and assessment of BHBA concentration in blood, cows were classified to four groups, control healthy cows (C = 16), subclinical ketosis (SCK = 10), cows with retained placenta (RP = 6), and clinical mastitis (CM = 6). BFT showed a significant decrease (p < 0.05) after parturition in all diseased groups compared with healthy. The plasma level of NEFA and BHBA showed a significant increase (p < 0.05) at 2 weeks a.p (antepartum) and 2 weeks p.p (postpartum) in RP and SCK than other groups, respectively. The plasma level of glucose showed a significant decrease (p < 0.05) at 2 weeks p.p in SCK group. The plasma level of insulin showed a significant decrease (p < 0.05) at 4 weeks a.p in RP group and in all groups after parturition. It could be concluded that production diseases induced clinical, biochemical, and subcutaneous fat changes in dairy cows.

Parity and Periparturient Period Affects Galectin Gene Expression in Holstein Cow Blood

The periparturient period in dairy cows is a crucial time influencing health, milk production and fertility. Galectins are receiving interest as therapeutic targets because of their roles in immune signaling pathways. The aim of this study was to evaluate the expression and modulation of galectin genes in periparturient cows with different parities. Twelve periparturient Holstein Friesian cows were grouped into 3 parities (1st parity, 2nd parity, 3rd parity) (N=4). Blood was taken during the periparturient period including 2 weeks close to parturition (close-up), and 7 days after parturition(c+7) in Paxgene tubes. Total RNA was isolated, reverse-transcribed to cDNA. With the use of Primer 3 online tool, specific primers (forward and reverse) for cow galectins LGALS- 1, 2, 3, 4, 7, 8, 9, 12, 15, GAPDH and β-actin were designed. Transcription of galectins was evaluated using Real-time PCR. Fold change in transcript abundance was calculated using the Livak method. GAPDH and β-actin served as internal controls. Enzyme-linked Immunosorbent Assay(ELISA) was used to detect and determine the concentrations of Galectins(Gal) in the plasma. All galectins tested were differentially expressed. LGALS1 and LGALS15 were transcribed only during late gestation, but undetected postpartum regardless of parity. Gal-1, -2,-4,-8 and -9 concentrations in plasma were high in periparturient cows compared to far-off cows. Gal9 concentration increased postpartum. Gal-2, Gal-3 and –Gal-12 concentrations were reduced in plasma postpartum compared to far-off cows. This study supports the idea that galectin signatures may be useful biomarkers and drug targets in dairy cows, especially during the periparturient period.

Periparturient lipolysis and oxylipid biosynthesis in bovine adipose tissues.

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

Linking Peripartal Dynamics of Ruminal Microbiota to Dietary Changes and Production Parameters.

During the peripartal period, proper acclimatization of rumen microorganisms to variations in nutritional management can facilitate the transition into lactation. This study characterized the temporal shifts in the composition and functional properties of ruminal microbiota during the periparturient period in dairy cows subjected to a typical two-tiered feeding management approach. Ruminal digesta samples from eight multiparous fistulated Holstein cows were collected on days −14, −7, 10, 20, and 28 relative to parturition. High-throughput Illumina sequencing of the V4 region of the bacterial 16S rRNA gene revealed distinct clustering patterns between pre- and postpartal ruminal microbiota. During the prepartal period, when the voluntary dry matter intake was lower, we observed strikingly lower inter-animal variations in the composition of the ruminal microbiota. Genera Ruminococcus and Butyrivibrio, which are considered major fibrolytic rumen dwellers, were overrepresented in the prepartal rumen ecosystem. In contrast, increased postpartal voluntary DMI was associated with enrichment of bacterial genera mainly consisting of proteolytic, amylolytic, and lactate-producer species (including Prevotella, Streptococcus, and Lactobacillus). These, together with the postpartal enrichment of energy metabolism pathways, suggested a degree of acclimatization of the ruminal microbiota to harvest energy from the carbohydrate-dense lactation diet. In addition, correlations between ruminal microbiota and parameters such as milk yield and milk composition underscored the metabolic contribution of this microbial community to the cow's performance and production.

Short communication: Associations between blood fatty acids, β-hydroxybutyrate, and α-tocopherol in the periparturient period in dairy cows: An observational study

The objective of the present study was to examine the relationships between blood concentrations of fatty acids, β-hydroxybutyrate (BHB), and α-tocopherol during the periparturient period in dairy cows. Blood samples were collected from 131 cows belonging to 4 different commercial dairy farms in southeastern Europe (Greece and Italy). We determined blood concentrations of fatty acids, BHB, and α-tocopherol at dry-off, at calving, and 30d postpartum. Results indicated that fatty acid concentrations were low at dry-off, reached maximum value at calving, and then declined at 30d postpartum. In fact, fatty acid concentrations at 30d postpartum were 50% lower than at calving. In contrast, BHB concentrations were low at dry-off, increased by 27% at calving, and continued to increase by another 20% at 30d postpartum. Overall, we found a weak correlation between fatty acids and BHB throughout the periparturient period. Concentrations of α-tocopherol were lowest at calving, and we detected no differences in α-tocopherol concentrations at dry-off or 30d postpartum. Negative correlations between fatty acids and α-tocopherol were highly significant at 30d postpartum and approached the level of significance at dry-off. However, both correlations became nonsignificant following the adjustment of α-tocopherol with cholesterol, indicating that the correlations were a reflection of changes in lipid transport. We found significant negative correlations (strong at dry-off and weak at 30d postpartum) between BHB and α-tocopherol after adjustment with cholesterol. The physiological basis for the negative correlations between BHB and α-tocopherol, especially that at dry-off, is not known and should not be taken to imply a cause-effect relationship. However, it opens the door to investigating the effects of vitamin E on liver function in dairy cows.

Influence of energy level and nicotinic acid supplementation on apoptosis of blood leukocytes of periparturient dairy cows

The periparturient period of dairy cows is accompanied by an immunosuppression that leaves the animal more susceptible to infections and metabolic disorders. Non-esterified fatty acids (NEFA) and beta-hydroxybutyrate (BHB) which peak shortly after parturition due to lipolysis are known to impair immune cell functions. Niacin with its well-known anti-lipolytic effect may have the ability to ameliorate this situation. Additionally, niacin shows also anti-inflammatory effects that may be beneficial to the immune status of the cow. To address this 29 multiparous and 18 primiparous German Holstein cows were subjected to four different feeding groups. They were fed either a ration with a high concentrate proportion of 60% (HC), or a low concentrate proportion of 30% (LC). After parturition both concentrate levels were reduced to 30% and increased again to 50% either within 16days (LC-group) or within 24days (HC-group). Half of the animals received either 24g per day of nicotinic acid from 42days prepartum until 24days postpartum (LC-NA, HC-NA) or no supplement (LC-CON, HC-CON). Apoptosis in polymorphonuclear leukocytes (PMN) and peripheral blood mononuclear cells (PBMC) was examined with an Annexin V and propidium iodide (PI) based fluorescence flow cytometry assay and distinguished into early apoptotic (Annexin V positive and PI negative) and late apoptotic (Annexin V and PI positive) cells. Additionally, the pro-apoptotic gene BAX, the effector caspase CASP3, and the anti-apoptotic genes BCL2 and BCL-xL, as well as the NFκB subunit RELA were quantified by real-time PCR in blood leukocytes. All variables showed time dependencies that were mainly related to parturition (p<0.01). Early apoptotic PBMC were significantly affected by concentrate level showing higher numbers of apoptotic cells in the HC groups (p=0.029). PBMC were characterized by a more pronounced apoptosis than PMN and seemed to be more susceptible to the changes that occur around parturition. The genes BAX and CASP3 were positively correlated (0.631) and their peak preceded the apoptotic peak around parturition in the blood leukocytes. The LC animals showed a decrease in BCL2 expression before parturition, whereas the HC animals showed a continuous increase in BCL2 mRNA abundance (p=0.059). RELA correlated stronger with the pro-apoptotic genes (0.715 and 0.650 with BAX and CASP3 respectively) and its expression was higher in primiparous than in multiparous cows (p=0.011). Nicotinic acid supplementation did show some influence in increasing numbers of early apoptotic PMN and late apoptotic PBMC between 42 and 100 DIM.

Changes in circulating adiponectin and tumour necrosis factor-α and their relationship with insulin resistance in periparturient dairy cows

Abstract Introduction: The aim of the study was to investigate changes in the serum levels of adiponectin and TNF-α, as well as insulin sensitivity, and to elucidate the possible relationship among the parameters and negative energy balance during the periparturient period of dairy cows. Material and Methods: Thirty primiparous Holstein dairy cows were selected for the study. Blood samples were collected from each cow seven days before the expected calving date, on the calving day, and 7, 14, and 21 days after calving. Blood non-esterified fatty acids (NEFA), β-hydroxybutyric acid (BHBA), glucose, insulin, adiponectin, and TNF- α levels were measured. Revised Quantitative Insulin Sensitivity Check Index (rQUICKI) was calculated using data on NEFA, insulin, and glucose concentrations. Results: When compared to prepartum levels, serum concentration of adiponectin significantly increased on day 21 postpartum. The rQUICKI increased and NEFA levels decreased on day 7 after parturition. Insulin and glucose levels decreased on days 7, 14, and 21 postpartum when compared with prepartum levels. BHBA levels decreased on day 21 and TNF- α concentration also decreased on days 7, 14, and 21 postpartum. Adiponectin levels positively correlated with NEFA during the preparturient period. Negative correlation was detected between adiponectin and rQUICKI on calving day and on 14th day after parturition. TNF- α concentration positively correlated with glucose levels on day 7 prepartum and on 21st day postpartum and with rQUICKI on 21st day postpartum. Negative correlation was detected between adiponectin level and insulin sensitivity. Conclusion: Based on the results of the study, we concluded that adiponectin could possibly increase insulin sensitivity when blood NEFA concentrations are elevated.