RESUMO

The aim of this work was to develop a liver tissue function index during the transition period of dairy cows managed in low-tropic conditions. In two farms, twenty crossbred and synthetic native cows during the peripartum period were selected, and blood samples were taken on days -30 and -15 prepartum, the calving day, and 7, 20, 35, 50, 65, 80 and 105 days postpartum for serum metabolic tests. On each measurement day, body condition scores (BCS) and parameters on nitrogen metabolism (total protein-TP, albumin-ALB, globulin-GLOB, urea), adipose tissue metabolism (cholesterol-COL, non-esterified fatty acids-NEFA) and two transaminases (alanine aminotransferase-ALT and aspartate aminotransferase-AST) were evaluated. Data analysis included the Spearman correlation, principal components, multiple linear regression and cluster analysis. Results showed that regarding the days after calving and BCS, a liver tissue function index can be constructed using the TP, urea, COL, ALT and NEFA. The estimated index generated three groupings, both by days after calving and BCS. In the former, the index discriminated the metabolic behavior in the prepartum, parturition and postpartum periods, while in the latter, the index discriminated between extreme (2.25, 2.50 and 4.25), slightly low (2.75 and 3.0) and slightly high (3.25 to 4) conditions. The results allow us to conclude that it is feasible to construct mathematical function indexes for liver function to monitor metabolic changes during highly demanding productive phases in dairy cows under tropical conditions.

RESUMO

This study aimed to evaluate the relationship between prepartum subclinical hypomagnesemia (pre-SHMg) and the occurrence of dystocia, metritis, clinical mastitis, lameness, and subclinical hypomagnesemia postpartum (post-SHMg) in pasture-based dairy cows. Also, the difference in means of prepartum magnesium (Mg) concentration by postpartum health events was evaluated. A total of 890 dairy cows from 32 commercial farms located in southern Chile were enrolled. Cows were examined twice, once between 30 and 3 days before and once between 3 and 30 days after calving. Blood samples were collected on both assessments, and cows were considered as having SHMg if serum total Mg < 0.65 mmol/L. On the postpartum visit, cows were evaluated for metritis and lameness. Information about clinical mastitis and dystocia was collected from on-farm records. Data were analyzed using multivariable mixed linear models and multivariable mixed logistic regression models. The overall prevalence of pre-SHMg was 9.9%, and its presence was associated with the occurrence of post-SHMg (odd ratio [OR] = 5.7; P < 0.0001) and metritis (OR = 3.1; P = 0.04). However, we did not detect an association between pre-SHMg and dystocia, clinical mastitis, or lameness after calving. Prepartum serum Mg concentrations were lower in cows that developed post-SHMg than those that did not (LSM ± SE = 0.75 ± 0.02 mmol/L vs. 0.83 ± 0.02 mmol/L; P < 0.0001). In conclusion, pre-SHMg was associated with a higher risk of post-SHMg and metritis in grazing dairy cows but not other postpartum health events.

Assuntos

Doenças dos Bovinos , Magnésio , Período Pós-Parto , Animais , Bovinos , Feminino , Chile/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/sangue , Gravidez , Magnésio/sangue , Magnésio/análise , Distocia/veterinária , Distocia/epidemiologia , Prevalência , Endometrite/veterinária , Endometrite/epidemiologia , Endometrite/sangue , Deficiência de Magnésio/veterinária , Deficiência de Magnésio/epidemiologia , Deficiência de Magnésio/sangue , Mastite Bovina/epidemiologia , Mastite Bovina/sangue , Coxeadura Animal/epidemiologia , Coxeadura Animal/etiologia , Coxeadura Animal/sangue , Indústria de Laticínios

RESUMO

Maternal status during the transition period can significantly impact the health and performance of Holstein dairy calves, with lasting effects on various variables. However, the relationship between maternal late gestation metabolic status, seasonality, and their impact on offspring remains unclear. This study aimed to assess the influence of maternal variables at calving on the performance, metabolism, and immunity of 28 dairy calves during their first month of life. Blood samples were collected from 28 Holstein cows at calving. Median results for maternal variables including non-esterified fatty acids (NEFA), ß-hydroxybutyrate (BHB), glucose, total protein (TP), albumin, triglycerides (TG), total cholesterol (TC), haptoglobin (Hp), body weight (BW), and body condition score (BCS) were determined. These median values served as a basis for categorizing the offspring into two groups based on their dams' high or low degree of each maternal variable. Additionally, calves were categorized by the season of birth (Spring vs. Winter), with 14 in each. Blood samples were collected from the calves at birth and on days 1, 7, 14, and 28 to assess IgG, biochemical parameters, and haptoglobin concentration. Reactive oxygen species (ROS) production by polymorphonuclear cells stimulated by various agents was also evaluated. Clinical assessments were conducted for diarrhea and bovine respiratory disease frequencies. Despite the overall health of the cows, differences were observed in the calves between maternal groups. Heavier cows with high maternal BCS tended to have larger offspring, while high maternal BCS was associated with increased diarrhea prevalence. Low maternal BCS resulted in a stronger innate immune response, indicated by higher ROS production. Calves from cows experiencing metabolic changes during calving displayed elevated Hp concentrations. Spring-born calves were larger but had lower serum IgG concentration and reduced innate immune response compared to winter-born calves. Additionally, spring-born calves exhibited higher Hp and increased diarrhea prevalence on day 28. These findings underscore the importance of the prenatal period in determining neonatal health and suggest further research to elucidate the long-term clinical implications of maternal effects on offspring health and growth. Investigating offspring constituents later in life can provide insight into the persistence of maternal effects over time.

RESUMO

BACKGROUND: The 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. RESULTS: In 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. CONCLUSIONS: To 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.

Assuntos

Proteínas de Checkpoint Imunológico , Receptor de Morte Celular Programada 1 , Feminino , Bovinos , Animais , Antígeno CTLA-4 , Lactação/fisiologia , Linfócitos T , Leite

RESUMO

Researchers have reported the benefits of feeding rumen-protected methionine (RPM) during the peripartum on the health parameters of dairy cows. Rumen-protected Met has reportedly improved milk yield, milk components, and liver health, but the literature is scarce on its effects in commercial herds. Therefore, we aimed to determine the effects of feeding RPM (Smartamine M, Adisseo Inc., Antony, France) prepartum (8 g/cow per day) and postpartum (15 g/cow per day) on performance, metabolic profile, and culling rate of Holstein cows in a commercial herd. One hundred sixty-six (n = 166) Holstein cows, 58 nulliparous and 108 parous, were randomly assigned to 1 of 2 dietary treatments, consisting of TMR top-dressed with RPM (RPMet; 2.35% and 2.24% Met of MP for close-up and fresh cows, respectively) or without (control [CON] 2.03% and 1.89% Met of MP for close-up and fresh cows, respectively), fed from 21 ± 6 d prepartum until 16 ± 5 d postpartum. From 17 DIM until dry-off, all cows received RPMet. Daily milk yield was recorded, and milk samples were collected in the first and second weeks after calving to determine their composition. Blood samples were collected before the morning feeding on -14, -7, +1, +7, and +14 d relative to calving. Mortality and morbidity were recorded during the first 60 DIM. Cows supplemented with RPMet had greater milk yield during the first 16 DIM (31.76 vs. 30.37 kg/d; SEM = 1.04, respectively), and had greater milk fat content (4.45 vs. 4.10%; SEM = 0.11, respectively), but not milk total protein (3.47 vs. 3.39%; SEM = 0.04, respectively) and casein contents (2.74 vs. 2.66%; SEM = 0.04, respectively) than CON cows. Cows in RPMet had increased plasma Met concentrations than cows in CON (24.9 vs. 21.0 µmol/L; SEM = 1.2, respectively). Although morbidity was similar between treatments, the culling rate from calving until 60 DIM was lower for RPMet cows than for CON cows (2.4% vs. 12.1%; SEM = 0.02). In conclusion, cows receiving RPMet have greater milk yield, improved milk fat content, and a lower culling rate at 60 DIM than CON cows.

Assuntos

Ração Animal , Dieta , Lactação , Metionina , Leite , Período Periparto , Rúmen , Animais , Bovinos , Metionina/metabolismo , Metionina/administração & dosagem , Feminino , Leite/química , Leite/metabolismo , Dieta/veterinária , Rúmen/metabolismo , Ração Animal/análise

RESUMO

The aims of this study were to estimate the genetic parameters for fat-to-protein ratio (F:P) within the first 90 days of lactation and to examine their genetic associations with daily milk yield (MY), somatic cell score (SCS), and calving interval between the first and second calving (IFSC) and between the second and third calving (ISTC) during the first three lactations of Holstein cows. We utilized 200,626 production-related data officially recorded from 77,436 cows milked two or three times a day from 2012 to 2022, sourced from the Holstein Cattle Breeders Association of Paraná State, Brazil. The (co)variance components were estimated using animal models, adopting the restricted maximum likelihood (REML) method with single-trait analysis (for heritability and repeatability) and two-trait analysis (for genetic and phenotypic correlations), per lactation. Regardless of lactation number, heritability estimates were relatively low, ranging from 0.08 ± 0.005 to 0.10 ± 0.003 for F:P; 0.08 ± 0.01 to 0.18 ± 0.005 for MY; 0.04 ± 0.01 to 0.07 ± 0.004 for SCS; and 0.03 ± 0.01 for both IFSC and ISTC. Repeatability estimates within the same lactation were low for F:P (ranging from 0.17 ± 0.002 to 0.19 ± 0.03), high for MY (between 0.50 ± 0.003 and 0.53 ± 0.002), and moderate to high for SCS (between 0.39 ± 0.003 and 0.44 ± 0.004). Genetic correlations between F:P and MY ranged from -0.26 ± 0.03 to -0.15 ± 0.02; F:P and SCS, from -0.06 ± 0.03 to -0.03 ± 0.08; F:P and IFSC, 0.31 ± 0.01; F:P and ISTC, 0.20 ± 0.01; MY and IFSC, 0.24 ± 0.05; and MY and ISTC, 0.13 ± 0.08. The fat-to-protein ratio during early lactation showed low genetic variability, regardless of lactation number. Furthermore, it was genetically correlated with MY, IFSC, and ISTC, although there is an antagonistic and unfavorable correlation between traits that can limit genetic progress.

Assuntos

Lactação , Leite , Feminino , Bovinos/genética , Animais , Brasil , Lactação/genética , Fenótipo

RESUMO

In the present work we aimed to study the effects of parenteral vitamin and mineral supplementation on hepatic fatty acid metabolism as well as on the oxidative stress biomarkers in biological samples of transition cows. The supplemented group (SG, n = 11) received a subcutaneous injection of 5 mL of vitamin A palmitate 35 mg/mL, vitamin E acetate 50 mg/mL plus other injection of 5 mL of copper edetate 10 mg/mL, zinc edetate 40 mg/mL, manganese edetate 10 mg/mL, and sodium selenite 5 mg/mL on days - 60, - 30, and 7 (± 3) relative to calving. The control group (CG, n = 11) received two subcutaneous injections of 5 mL of 9 mg/mL sodium chloride at the same times of the SG. Blood, urine, and liver biopsies were sampled 21 (± 3) days before the expected calving date and 7 and 21 (± 3) days after calving. Results revealed that supplemented animals had higher glutation peroxidase (GSH-Px) activity, lower and higher concentration of 3-nitrotyrosine (3-NT) in the liver and plasma, respectively, higher expression of the mitochondrial beta-oxidation enzyme carnitine palmitoyltransferase 1 in the liver, and lower content of hepatic triacylglycerol, mirroring plasma liver function parameters. No differences between groups were found in the superoxide dismutase activity, MDA concentrations, the protein abundance of peroxisomal acyl-CoA oxidase 1, diacylglycerol O-acyltransferase 1, and peroxisome proliferator-activated receptor alpha. These results suggest that the vitamin and mineral supplementation provided to dairy cows had a beneficial effect on GSH-Px activity, hepatic 3-NT concentration, and on the metabolic adaptation during the peripartum period.

Assuntos

Fígado , Vitaminas , Feminino , Bovinos , Animais , Vitaminas/farmacologia , Ácido Edético , Fígado/metabolismo , Estresse Oxidativo , Suplementos Nutricionais , Minerais/metabolismo , Ácidos Graxos/metabolismo , Biomarcadores/metabolismo , Lactação , Leite/metabolismo , Dieta/veterinária

RESUMO

This study aimed to evaluate the effects of parity, body condition score (BCS) at calving, and milk yield on the metabolic profile of Gyr (Zebu) cows. Healthy cows in late pregnancy were grouped according to parity (primiparous, biparous, and multiparous); to BCS scale at calving (high-HBCS and normal-NBCS); and to milk yield (high-HP and moderate-MP production). BCS was assessed, and blood samples were collected on -21, -7, 0, 7, 21, and 42 days relative to parturition. The concentrations of non-esterified fatty acids (NEFA), beta-hydroxybutyrate (BHB), cholesterol, glucose, total protein (TP), albumin, total calcium (Ca), phosphorus (P), and magnesium (Mg); and activities of aspartate aminotransferase and gamma-glutamyltransferase were measured. Data were analyzed by two-way repeated measures ANOVA. The frequencies of high lipomobilization, subclinical ketosis, subclinical hypocalcemia (SCH), and the occurrence of diseases during early lactation were established. Regardless of grouping, NEFA, BHB, and cholesterol increased during early lactation; glucose showed higher values at calving; TP and albumin were higher at 21 and 42 DIM; and Ca, P, and Mg were lower at calving. Parity had little effect on the metabolic profile, HBCS did not differ from NBCS cows, and HP did not differ from MP cows in most metabolites. High lipomobilization in early lactation and SCH at calving were the most common imbalances but were not related to postpartum diseases. High-yielding Gyr cows have a balanced metabolic profile during the transition period, with few biologically relevant effects of parity, BCS at parturition, or milk yielded.

RESUMO

This study aimed to analyze the possible relationship between days to conception and different oxidative stress (OS) biomarkers and liver functional parameters in multiparous dairy cows. Besides, a fast reliable method for the accurate measurement of malondialdehyde (MDA) by liquid chromatography-tandem mass spectrometry was developed in several matrices. During lactation, the days to conception of 28 cows were determined for a retrospective study. According to this parameter, cows were divided into two groups: high and low days to conception (HDC and LDC, respectively). Blood, urine and liver biopsies were sampled 21 days before the expected calving date, and 7 and 21 days after calving. The method developed for MDA was validated according to international requirements. The lower limit of quantification was 0.25 µmol/L for plasma and urine and 10.00 µmol/L for liver tissue. No differences between groups were observed in the systemic concentration of non-esterified fatty acids, ß-hydroxybutyric acid and liver triacylglycerol content (P > 0.05). Cholesterol concentration was higher in the LDC than in the HDC group (P < 0.05). Plasma 3-nitrotyrosine (3-NT) concentration was lower in the LDC than in the HDC group on day 21 post-calving (P < 0.05). Superoxide dismutase activity was higher in the LDC than in the HDC group (P < 0.05). Particularly, in the liver, 3-NT and MDA concentrations were lower in the LDC than in the HDC group (P < 0.05). These results allow inferring that the amelioration of OS biomarkers in plasma and liver could be related to a better reproductive performance of dairy cows.

Assuntos

Lactação , Estresse Oxidativo , Feminino , Bovinos , Animais , Estudos Retrospectivos , Argentina , Fígado/metabolismo , Biomarcadores/análise , Leite , Dieta/veterinária , Período Pós-Parto

RESUMO

This study aimed to evaluate the impact of body condition score (BCS) at calving, parity, and the calving season on the performance of dairy cows and their offspring. Data from 521 Holstein cows that calved a female calf and had their BCS evaluated at calving from a single commercial farm located in Southern Brazil were used. Cows were categorized into five BCS classes: class 1: <3.0 (n = 19), class 2: 3.0-3.25 (n = 134), class 3: 3.5-3.75 (n = 160), class 4: 4.0-4.25 (n = 142), and class 5: >4.25 (n = 66). Data were also categorized by calving order (primiparous and multiparous dams) and by calving season. The study was designed as a prospective cohort study. Variables with normal distribution were analyzed by the MIXED procedure of SAS, while binary outcomes were analyzed by the GLIMMIX procedure of SAS. Daughters from primiparous dams were born lighter (39.1 ± 0.42 vs. 41.4 ± 0.29 kg, p < 0.01), but they had the same weights as the daughters from multiparous cows at weaning (121.5 ± 1.67 vs. 120.4 ± 1.58 kg, p = 0.20). As expected, primiparous cows showed lower (p < 0.01) 305-day milk yields than multiparous ones: 8633 ± 363 vs. 10,761 ± 249 kg, respectively. Regarding the calving season, cows that calved in the winter were the most productive ones, and those that calved in the fall had lower milk yields (p = 0.01). Calves born in the winter were heavier at birth (p < 0.01), calved younger (p = 0.04), and produced more milk at first lactation (p = 0.03). The BCS class had an impact (p < 0.01) on calf birth weights; daughters from Class 1 cows (BCS < 3.0) were lighter (38.0 ± 1.0 kg) than the calves from Class 5 cows with a BCS > 4.25 (41.9 ± 0.57 kg). Calves from dams with a BCS < 3 (Class 1) had a 31.8% culling rate until weaning, while calves from cows with a BCS of 3.0-3.25 (Class 2) had a 9.6% culling rate (p = 0.12). These results suggest that maternal and environmental factors, such as calving season and parity, in addition to the dams' body condition score at calving, are associated with different offspring performances.