Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 4.322
Filtrar
1.
Theriogenology ; 141: 128-133, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31539641

RESUMO

The objective of this experiment was to determine if circulating concentrations of pregnancy associated glycoproteins (PAG) on day 24 of gestation can be utilized to diagnose pregnancy and embryo viability in beef cattle. Postpartum beef cows (n = 677) and heifers (n = 127) were exposed to a 7-day CO-Synch + CIDR estrus synchronization protocol followed by fixed-time AI (FTAI) on day 0. Blood samples were collected at day 24 after TAI to assess circulating concentrations of PAG utilizing an in-house ELISA. Pregnancy diagnosis was performed 30 and 100 days after FTAI via transrectal ultrasonography. Mean circulating PAG concentration at day 24 differed (P < 0.001) between animals diagnosed pregnant and non-pregnant at day 30 (1.69 ±â€¯0.10 ng/mL vs 0.30 ng/mL ±â€¯0.07 ng/mL; mean ±â€¯SEM; respectively). Pregnant heifers had increased PAG concentration at day 24 compared with pregnant cows (P < 0.01; 3.29 ±â€¯0.36 ng/mL vs 1.39 ±â€¯0.10 ng/mL, respectively). Based on receiver operating characteristic (ROC) curve analysis, serum concentration of PAG at day 24 ≥ 0.33 ng/mL in cows and ≥0.54 ng/mL in heifers was 95% accurate at determining pregnancy status at day 30. Heifers that experienced late embryonic mortality between day 30 and 100 of gestation had decreased circulating concentrations of PAG on day 24 (2.02 ng/mL ±â€¯0.73) compared with heifers that maintained an embryo until day 100 (3.69 ng/mL ±â€¯0.39; P = 0.02). However, there was no difference in day 24 PAG concentration (P = 0.39) between cows that maintained or lost a pregnancy (1.31 ng/mL ±â€¯0.25 vs 0.92 ng/ml ±â€¯0.50). In summary, circulating PAG concentration on day 24 of gestation may be a useful marker for early pregnancy detection in beef cattle, and might be a potential marker for predicting embryonic loss.


Assuntos
Aborto Animal/diagnóstico , Doenças dos Bovinos/diagnóstico , Bovinos/sangue , Proteínas da Gravidez/sangue , Testes de Gravidez/veterinária , Animais , Doenças dos Bovinos/sangue , Sincronização do Estro , Feminino , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Paridade , Gravidez
2.
J Dairy Sci ; 103(1): 325-339, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677835

RESUMO

The objectives were to evaluate the effects of feeding different amounts of supplemental live yeast (LY) on performance and digestion of cows under heat stress. Sixty Holstein cows, 27 multiparous and 33 primiparous, were blocked by parity and milk yield in the first 20 d in milk (DIM) and randomly assigned to receive 0, 0.5, or 1.0 g/d of LY, resulting in daily intakes of 0, 14.2, and 37.6 billion cells, respectively, of Saccharomyces cerevisiae strain CNCM I-1077 from 30 to 107 DIM. Cows were milked twice daily, dry matter intake (DMI) and milk yield were measured daily, and milk components, body weight, and body condition were measured weekly. Blood was sampled weekly and plasma analyzed for concentrations of glucose, fatty acids, urea N, haptoglobin, serum amyloid A, and acid-soluble protein. Digestibility of nutrients was measured in the last 2 wk of the experiment. Ruminal fluid was collected on 2 consecutive days 6 h after the morning feeding for measurements of pH, concentrations of short chain fatty acids, and NH3-N. Feeding behavior was observed for 48 h on experiment d 21 and 63. The mean ambient temperature was 26.8°C, humidity was 83.2%, and the temperature and humidity index ranged from 73 to 81. Treatment did not affect rectal temperature (38.9 ± 0.04°C) or DMI but increased yield of energy-corrected milk (ECM; 35.2 vs. 36.1 vs. 37.2 kg/d for 0, 0.5, and 1.0 g/d, respectively) and efficiency of conversion of DM into ECM (1.70, 1.79, and 1.83 for 0, 0.5, and 1 g/d, respectively). Feeding LY increased digestibility of crude protein (65.1 vs. 68.8 vs. 70.4%) and neutral detergent fiber (NDF; 47.5 vs. 49.2 vs. 55.2%), and concentration of acetate (64.7 vs. 69.1 vs. 72.2 mM), which resulted in increased concentration of total short chain fatty acids in ruminal fluid (110.3 vs. 117.7 vs. 121.4 mM). Mean ruminal pH increased (5.99 vs. 6.03 vs. 6.26), and proportion of cows with pH <5.8 decreased linearly (42.9 vs. 34.9 vs. 7.7%) with increasing inclusion of LY. Concentrations of acute-phase proteins decreased with increasing amount of LY. Some aspects of feeding behavior were altered by LY, and meal size reduced quadratically (3.2, 3.5, and 2.9 kg of DM, respectively), whereas interval between rumination bouts tended to reduce linearly (122, 96.5, and 90.7 min, respectively) with increasing dose of LY. Chewing time per kilogram of NDF tended to increase linearly (71.6, 71.3, and 81.6 min/kg, respectively) with increasing dose of LY. The estimated net energy for lactation of the diet increased 5.2%, from 1.72 Mcal/kg of DM for 0 g of LY to 1.81 Mcal/kg for 1 g of LY. Feeding 1 g of LY/d to cows under heat stress increased yield of ECM and efficiency of feed conversion into ECM, improved diet digestibility, and increased ruminal fluid pH; these responses might be related either to direct effects of LY on ruminal microbial activity or to changes in feeding behavior that improved digestion of cows in heat stress.


Assuntos
Ração Animal/análise , Bovinos/fisiologia , Comportamento Alimentar , Resposta ao Choque Térmico/efeitos dos fármacos , Fermento Seco/administração & dosagem , Animais , Análise Química do Sangue/veterinária , Bovinos/sangue , Dieta/veterinária , Ácidos Graxos Voláteis/metabolismo , Feminino , Lactação/fisiologia , Leite/metabolismo , Gravidez
3.
J Dairy Sci ; 103(1): 922-928, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31733856

RESUMO

Our objectives were to examine the stability of (1) serum and plasma total calcium (tCa) after delayed separation of bovine whole blood stored at 4°C, and (2) frozen serum and plasma tCa stored at -80°C. Whole blood was collected from 19 cows into vacutainer tubes (Becton Dickinson, Franklin Lakes, NJ) containing no additives (serum) or lithium heparin (plasma). Baseline tCa concentrations (0-h tCa) were determined on serum and plasma harvested within 2 h of blood collection. To evaluate the effect of prolonged whole blood storage at 4°C, serum and plasma were harvested from samples after 6, 24, 48, 72 h, and 7 and 14 d of storage. For evaluation of the stability of frozen serum and plasma stored at -80°C, samples were stored for 7 d and 1, 3, 6, and 12 mo. The median 0-h tCa concentration for serum and plasma was 2.25 mmol/L (range: 1.58 to 2.60 mmol/L) and 2.28 mmol/L (range: 1.60 to 2.65 mmol/L), respectively. The average difference in tCa from 0-h samples ranged from -0.02 to 0.03 mmol/L for all samples stored at either 4 or -80°C. The median within-cow variability for whole blood samples stored at 4°C was 1.1 and 1.0% for serum and plasma, respectively, and for serum and plasma stored at -80°C was 1.1 and 1.3%, respectively. When whole blood was stored at 4°C, no differences in serum or plasma tCa concentrations were observed across the evaluated time points as compared with 0-h concentrations. Similarly, frozen serum and plasma stored at -80°C remained stable up to 12 mo. Therefore, our findings show that whole blood samples may be stored for at least 14 d at 4°C in vacutainer tubes containing no additives or lithium heparin without biologically important changes in tCa concentrations beyond expected analytical variation. Additionally, serum or plasma may be stored at -80°C for up to 12 mo with no effect on tCa concentrations.


Assuntos
Coleta de Amostras Sanguíneas/veterinária , Cálcio/sangue , Bovinos/sangue , Animais , Testes Diagnósticos de Rotina , Feminino , Temperatura Ambiente
4.
Pol J Vet Sci ; 22(4): 695-701, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867920

RESUMO

Progesterone (P4) is responsible for the main reproduction processes. Concentration of P4 varies widely among different determination methods, and interpretation of these values may be difficult. The objective of the current study was to assess the agreement of three different enzyme immunoassays (ELISA) in relation to radioimmunoassay (RIA) of P4 concentration assessment of beef cow serum samples. Samples were collected randomly considering high (pregnant cows) and low (non-pregnant cows) P4 concentrations. Depending on the P4 assessment method, four groups were created as follows: Group 1 - direct samples assessed by ELISA, Group 2 - extracted samples assessed by ELISA, Group 3 - samples assessed by automated ELISA, and Group 4 - samples assessed by RIA. The mean progesterone concentration was 4.50 ng/mL, 1.24 ng/mL, 4.07 ng/mL and 4.39 ng/mL from Group 1 to Group 4, respectively. The mean difference (MD) between Group 1, Group 2 and Group 3 individually compared with Group 4 was -0.10 ± 1.24 ng/mL, 3.15 ± 3.58 ng/mL and 0.33 ± 1.42 ng/mL, and the 95% confidence interval (CI) for the differences (s) was from -0.99 to 0.78 ng/mL, from 0.59 to 5.71 ng/mL, and from -0.69 to 1.34 ng/mL, respectively. The confidence interval for the lower and upper limit of the agreement ranged from -4.12 to -1.05 ng/mL and from 0.84 to 3.91 ng/mL between Group 1 and Group 4, from -8.45 to 0.42 ng/ mL and from 5.88 to 14.75 ng/mL between Group 2 and Group 4, from -4.29 to -0.76 ng/mL, and from 1.41 to 4.94 ng/mL between Group 3 and Group 4. Our findings show that the best agreement with RIA was observed for Group 1 and Group 3, while the agreement in the extraction method was least accurate.


Assuntos
Análise Química do Sangue/veterinária , Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Progesterona/sangue , Radioimunoensaio/veterinária , Animais , Análise Química do Sangue/métodos , Feminino
5.
Pol J Vet Sci ; 22(4): 789-792, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867924

RESUMO

We measured the bone-specific alkaline phosphatase (ALP) isoenzyme activity in 67 plasma samples from 14 newborn Holstein calves using both a conventional method (featuring heat inactivation) and a commercial agarose gel electrophoresis (AGE) kit; the relevant isoenzymes were termed bone-specific ALP (BAP) and ALP isoenzyme 3 (ALP3). We explored whether the AGE kit afforded reliable data when used to analyze samples from Holstein calves. The blood was collected from the jugular vein of each calf immediately prior to the first colostrum feeding (pre-feeding), 20 and 40 h after pre-feeding, and on days 4 and 7; whereas three samples (from three calves) were not obtained. The total plasma ALP activity varied widely, exceeding the ranges of reference values. On electrophoresis, 52 of 67 plasma samples (77.6 %) clearly contained both ALP isoenzyme 2 and ALP3, as did control human serum. The total ALP activity of the 52 samples ranged from 166-1989 U/L (median: 1013 U/L), whereas the values for the other 15 samples (22.4%) exhibiting abnormal isoenzyme fractionation ranged from 1014-5118 U/L (median: 1780 U/L). In the 52 plasma samples exhibiting clearly separated isoenzymes, ALP3 and BAP activities were strongly positively correlated as revealed by Deming regression (y = 0.93x + 22.6, p⟨0.0001) and Bland-Altman analysis (ALP3/BAP activities limit of agreement: -5.1%). Thus, the AGE kit yields useful information on newborn calves, and can replace the conventional method when the total plasma ALP activity is less than approximately 1000 U/L.


Assuntos
Fosfatase Alcalina/sangue , Osso e Ossos/enzimologia , Bovinos/sangue , Eletroforese em Gel de Ágar/veterinária , Fosfatase Alcalina/metabolismo , Animais , Animais Recém-Nascidos , Isoenzimas/sangue , Kit de Reagentes para Diagnóstico
6.
Pol J Vet Sci ; 22(4): 769-775, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31867935

RESUMO

One of the effective reproductive management programs in dairy cattle is the accurate detection of pregnancy. A total of 204 non-descriptive cows were examined for pregnancy before slaughter in Sulaimani abattoir. Examinations were done by rectal palpation and enzyme-linked immunosorbent assay (ELISA) to measure the levels of progesterone and bovine pregnancy- -associated glycoproteins (bPAGs) in their blood. Detection of a live conceptus in the uterus of slaughtered cows was used as the gold standard to determine the accuracy of the three pregnancy detection methods. The results showed that the accuracies of rectal palpation, progesterone assay, and bPAGs assay in the diagnosis of pregnancy were 87.2%, 84.8%, and 97.05%, respectively. The bPAGs assay scored the highest sensitivity (100%) for detection of pregnancy, followed by the progesterone assay (92.3%) and rectal palpation (84.6%). In addition, the specificity of the bPAGs assay was the highest (96.0%), while progesterone assay exhibited the lowest specificity (80.1%) and rectal palpation showed a specificity rate of (88.8%). In conclusion, the best method for the detection of either for early or late pregnancy in cows was the bPAGs assay, which gave the lowest number of false-positive and false-negative results.


Assuntos
Bovinos/sangue , Ensaio de Imunoadsorção Enzimática/veterinária , Glicoproteínas/sangue , Proteínas da Gravidez/sangue , Testes de Gravidez/veterinária , Animais , Feminino , Inseminação Artificial/veterinária , Gravidez , Testes de Gravidez/métodos , Sensibilidade e Especificidade
7.
J Dairy Sci ; 102(12): 11180-11192, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587908

RESUMO

Enhancing micronutrient (i.e., mineral and vitamin) concentrations within milk and serum from dairy cows is important for both the health of the cow and the nutritive value of the milk for human consumption. However, a good understanding of the genetics underlying the micronutrient content in dairy cattle is needed to facilitate such enhancements through feeding or breeding practices. In this study, milk (n = 950) and serum (n = 766) samples were collected from Holstein-Friesian dairy cows (n = 479) on 19 occasions over a 59-mo period and analyzed for concentrations of important elements. Additionally, a subset of 256 milk samples was analyzed for concentrations of vitamin B12. Cows belonged to 2 genetic lines (average and highest genetic merit for milk fat plus protein yield) and were assigned to 1 of 2 diets based on either a by-product or homegrown ration. Univariate models accounting for repeated records were used to analyze element and vitamin B12 data and investigate the effect of genotype and feeding system as well as derive estimates of variance components and genetic parameters. Bivariate models were used to study correlations both within and between milk and serum. Only concentrations of Hg in milk were seen to be affected by genotype, with higher concentrations in cows with high genetic merit. In contrast, element concentrations were influenced by feeding system such that cows fed the homegrown diet had increased milk concentrations of Ca, Cu, I, Mn, Mo, P, and K and increased serum concentrations of Cd, Cu, Fe, Mo, and V. Cows on the by-product diet had increased milk concentrations of Mg, Se, and Na and increased serum concentrations of P and Se. Heritability (h2) estimates were obtained for 6 milk and 4 serum elements, including Mg (h2milk = 0.30), K (h2serum = 0.18), Ca (h2milk = 0.20; h2serum = 0.12), Mn (h2milk = 0.14), Cu (h2serum = 0.22), Zn (h2milk = 0.24), Se (h2milk = 0.15; h2serum = 0.10), and Mo (h2milk = 0.19). Significant estimates of repeatability were observed in all milk and serum quantity elements (Na, Mg, P, K, and Ca) as well as 5 milk and 7 serum trace elements. Only K in milk and serum was found to have a significant positive genetic and phenotypic correlation (0.52 and 0.22, respectively). Significant phenotypic associations were noted between milk and serum Ca (0.17), Mo (0.19), and Na (-0.79). Additional multivariate analyses between measures within sample type (i.e., milk or serum) revealed significant positive associations, both phenotypic and genetic, between some of the elements. In milk, Se was genetically correlated with Ca (0.63), Mg (0.59), Mn (0.40), P (0.53), and Zn (0.52), whereas in serum, V showed strong genetic associations with Cd (0.71), Ca (0.53), Mn (0.63), Mo (0.57), P (0.42), K (0.45), and Hg (-0.44). These results provide evidence that element concentrations in milk and blood of dairy cows are significantly influenced by both diet and genetics and demonstrate the potential for genetic selection and dietary manipulation to alter nutrient concentration to improve both cow health and the healthfulness of milk for human consumption.


Assuntos
Bovinos/genética , Leite/química , Animais , Cruzamento , Bovinos/sangue , Dieta/veterinária , Feminino , Testes Genéticos/veterinária , Lactação , Proteínas do Leite/análise , Minerais/análise , Valor Nutritivo , Oligoelementos/metabolismo , Vitamina B 12/análise
8.
J Dairy Sci ; 102(12): 11142-11152, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31587909

RESUMO

In this study, we estimated genetic parameters and genomic prediction accuracies of serum biomarkers of health in early-lactation dairy cows. A single serum sample was taken from 1,393 cows, located on 14 farms in southeastern Australia, within 30 d after calving. Sera were analyzed for biomarkers of energy balance (ß-hydroxybutyrate and fatty acids), macromineral status (Ca and Mg), protein nutritional status (urea and albumin), and immune status (globulins, albumin-to-globulin ratio, and haptoglobin). After editing, 47,162 SNP marker genotypes were used to estimate genomic heritabilities and breeding values (GEBV) for these traits in ASReml. Heritabilities were low for ß-hydroxybutyrate, fatty acids, Ca, Mg, and urea (0.09 ± 0.04, 0.18 ± 0.05, 0.07 ± 0.04, 0.19 ± 0.06, and 0.18 ± 0.05, respectively), and moderate for albumin, globulins, and albumin-to-globulin ratio (0.27 ± 0.06, 0.46 ± 0.06, and 0.41 ± 0.06, respectively). The heritability of haptoglobin concentration was close to 0. The magnitude of genetic correlations between traits (estimated using bivariate models) varied considerably (0.01 to 0.96), and standard errors of these correlations were high (0.02 to 0.44). Interestingly, the direction of most genetic correlations was favorable, suggesting that selecting for more optimal concentrations of one biomarker may result in more optimal concentrations of other biomarkers. Correlations between biomarker GEBV and existing breeding values for survival, somatic cell count, and daughter fertility were small to moderate (0.07 to 0.45) and favorable, whereas correlations with breeding values for milk production traits were small (≤0.15). Accuracies of GEBV were evaluated by using 5-fold cross validation, and by calculating accuracies from prediction error variances associated with the GEBV. Accuracies of GEBV predicted using 5-fold cross validation were low (0.05 to 0.27), whereas the means of individual accuracies were greater, ranging from 0.31 to 0.51. Although increasing the size of the reference population should theoretically improve accuracies, our results suggest that genomic prediction of health biomarkers may allow identification of cows that are less susceptible to diseases in early lactation.


Assuntos
Biomarcadores/sangue , Bovinos/sangue , Genômica , Indicadores Básicos de Saúde , Lactação/genética , Ácido 3-Hidroxibutírico/sangue , Animais , Cruzamento , Bovinos/genética , Ácidos Graxos/sangue , Feminino , Fertilidade , Genótipo , Fenótipo
9.
J Dairy Sci ; 102(12): 11250-11259, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606216

RESUMO

The objective of this study was to assess the effect of exercise and pasture turnout on lying behavior, labor length, and cortisol concentrations around the time of parturition in dairy cows. Twenty-nine primiparous and 31 multiparous, pregnant, nonlactating Holstein (n = 58) and Jersey × Holstein cross (n = 2) dairy cows were assigned to control (n = 20), exercise (n = 20), or pasture (n = 20) treatments at dry-off using rolling enrollment. Control cows remained in the dry cow group pen. Exercise cows were removed from the dry cow group pen 5 times per week and walked for 1.4 ± 0.1 h at 1.88 ± 0.58 km/h. Pasture cows were moved to an outdoor paddock 5 times per week for 1.8 ± 0.3 h/d. Cows were housed in deep-bedded sand freestalls in a naturally ventilated, 4-row freestall barn. Cows were moved into maternity pens on the day of projected calving or when cows displayed signs that calving was imminent (restlessness, raised or lifted tail, ruptured amniotic sac, or swollen vulva), and treatments were discontinued. Cameras continuously recorded cows from entry into the pen until farm staff noted a calf, and one observer continuously watched video for two visually observable periods throughout the calving process: time from initial observation of amniotic sac to initial observation of calf's feet, and time from initial observation of calf's feet to full expulsion of calf. Assisted calvings were excluded. Accelerometers were attached to the rear fetlocks of cows 3 d before dry-off and removed 14 d postpartum. Activity was summarized by day for the 7 d before and after delivery time recorded from video observation into lying time (hours per day), lying bout frequency (bouts per day), lying bout duration (minutes per bout), and steps (number per day). Plasma total cortisol concentration was measured on d 0 and 3 postpartum and determined by a radioimmunoassay procedure using a commercially available kit. Data were analyzed using mixed linear model. During calving, time from appearance of the amniotic sac to appearance of the calf's feet was longer for pasture cows compared with control. Control cows engaged in fewer lying bouts and less overall lying time compared with pasture and exercise cows. Cortisol concentrations were higher on the day of calving compared with 3 d later, regardless of treatment. Understanding the effects of lying alterations around calving and increases in labor period length may allow for physical activity recommendations for late-gestation dairy cows.


Assuntos
Bovinos/fisiologia , Hidrocortisona/sangue , Condicionamento Físico Animal , Prenhez/fisiologia , Animais , Bovinos/sangue , Feminino , Lactação , Paridade , Parto , Período Pós-Parto , Gravidez , Prenhez/sangue , Descanso
10.
Anim Genet ; 50(6): 744-748, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31531898

RESUMO

We aimed to identify QTL for serum electrolyte traits by performing a GWAS of calcium, chloride, sodium, potassium and magnesium ion concentrations in Chinese Holstein cattle. We detected five SNPs that had significant associations with calcium ion concentrations and identified GATA2 from Bos taurus chromosome (BTA)22 as having the highest significance. Among the genes with significant results, we speculate that TMEM123 might be related to calcium channel proteins according to the functions of the TMEM family.


Assuntos
Bovinos/genética , Eletrólitos/sangue , Estudo de Associação Genômica Ampla , Locos de Características Quantitativas , Animais , Bovinos/sangue , Bovinos/classificação , Bovinos/metabolismo , Polimorfismo de Nucleotídeo Único
11.
J Anim Sci ; 97(11): 4657-4667, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31563947

RESUMO

We examined the effects of dietary supplementation of a Saccharomyces cerevisiae-based direct-fed microbial (DFM) on the growth performance, whole-blood immune gene expression, serum biochemistry, and plasma metabolome of newly weaned beef steers during a 42 d receiving period. Forty newly weaned Angus crossbred steers (7 d post-weaning; 210 ± 12 kg of BW; 180 ± 17 d of age) from a single source were stratified by BW and randomly assigned to 1 of 2 treatments: basal diet with no additive (CON; n = 20) or a basal diet top-dressed with 19 g of the DFM (PROB; n = 20). Daily DMI and weekly body weights were measured to calculate average daily gain (ADG) and feed efficiency (FE). Expression of 84 immune-related genes was analyzed on blood samples collected on days 21 and 42. Serum biochemical parameters and plasma metabolome were analyzed on days 0, 21, and 42. On day 40, fecal grab samples were collected for pH measurement. Compared with CON, dietary supplementation of PROB increased final body weight (P = 0.01) and ADG (1.42 vs. 1.23 kg; P = 0.04) over the 42 d feeding trial. There was a tendency for improved FE with PROB supplementation (P = 0.10). No treatment effect (P = 0.24) on DMI was observed. Supplementation with PROB increased (P ≤ 0.05) the concentrations of serum calcium, total protein, and albumin. Compared with CON, dietary supplementation with PROB increased (P ≤ 0.05) the expression of some immune-related genes involved in detecting pathogen-associated molecular patterns (such as TLR1, TLR2, and TLR6), T-cell differentiation (such as STAT6, ICAM1, RORC, TBX21, and CXCR3) and others such as TNF and CASP1, on day 21 and/or day 42. Conversely, IL-8 was upregulated (P = 0.01) in beef steers fed CON diet on day 21. Plasma untargeted plasma metabolome analysis revealed an increase (P ≤ 0.05) in the concentration of metabolites, 5-methylcytosine and indoleacrylic acid involved in protecting the animals against inflammation in steers fed PROB diet. There was a tendency for lower fecal pH in steers fed PROB diet (P = 0.08), a possible indication of increased hindgut fermentation. This study demonstrated that supplementation of PROB diet improved the performance, nutritional status, and health of newly weaned beef steers during a 42 d receiving period.


Assuntos
Bovinos/fisiologia , Suplementos Nutricionais/análise , Metaboloma , Saccharomyces cerevisiae , Ração Animal/análise , Bem-Estar do Animal , Animais , Bovinos/sangue , Bovinos/genética , Bovinos/crescimento & desenvolvimento , Dieta/veterinária , Fezes/química , Fermentação , Regulação da Expressão Gênica , Concentração de Íons de Hidrogênio , Masculino , Desmame
12.
Bull Environ Contam Toxicol ; 103(5): 739-744, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31520140

RESUMO

The aim of this study is to determine seasonal changes in the blood levels of some heavy metals in three Turkey-specific cattle breed: Native Land (NL), Grizzle Race (GR), and South Anatolian Red (SR). Blood samples were collected in summer and winter seasons from a total of 180 cattle aged 12-24 months. The levels of the essential (Zn, Cu, Fe, Co etc.) and non-essential (Cd, Hg, As, Cr, Pb, etc.) heavy metals were analyzed. All heavy metal levels, except that of Co, were significantly higher (p < 0.05) in SR in both seasons compared to the other species. In all breeds, Fe and Co levels were statistically higher (p < 0.05) in the summer season while Mn level was higher (p < 0.05) in the winter season. The levels of all metals analyzed are within the internationally acceptable limits for cattle breeds.


Assuntos
Bovinos/sangue , Monitoramento Ambiental/métodos , Metais Pesados/sangue , Poluentes Químicos da Água/sangue , Animais , Estações do Ano , Especificidade da Espécie , Turquia
13.
J Dairy Sci ; 102(12): 11298-11307, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31521353

RESUMO

Dairy cows commonly experience an unbalanced energy status in early lactation, and this condition can lead to the onset of several metabolic disorders. Blood metabolic profile testing is a valid tool to monitor and detect the most common early lactation disorders, but blood sampling and analysis are time-consuming and expensive, and the procedure is invasive and stressful for the cows. Mid-infrared (MIR) spectroscopy is routinely used to analyze milk composition, being a cost-effective and nondestructive method. The present study aimed to assess the feasibility of using routine milk MIR spectra for the prediction of main blood metabolites in dairy cows, and to investigate associations between measured blood metabolites and milk traits. Twenty herds of Holstein Friesian, Brown Swiss, or Simmental cows located in Northeast Italy were visited 1 to 4 times between December 2017 and June 2018, and blood and milk samples were collected from all lactating cows within 35 d in milk. Concentrations of main blood metabolites and milk MIR spectra were recorded from 295 blood and milk samples and used to develop prediction models for blood metabolic traits through backward interval partial least squares analysis. Blood ß-hydroxybutyrate (BHB), urea, and nonesterified fatty acids were the most predictable traits, with coefficients of determination of 0.63, 0.58, and 0.52, respectively. On the contrary, predictive performance for blood glucose, triglycerides, cholesterol, glutamic oxaloacetic transaminase, and glutamic pyruvic transaminase were not accurate. Associations of blood BHB and urea with their respective contents in milk were moderate to strong, whereas all other correlations were weak. Predicted blood BHB showed an improved performance in detecting cows with hyperketonemia (blood BHB ≥ 1.2 mmol/L), compared with commercial calibration equation for milk BHB. Results highlighted the opportunity of using milk MIR spectra to predict blood metabolites and thus to collect routine information on the metabolic status of early-lactation cows at a population level.


Assuntos
Bovinos/sangue , Leite/química , Espectrofotometria Infravermelho/veterinária , Ácido 3-Hidroxibutírico/sangue , Animais , Glicemia/análise , Ácidos Graxos não Esterificados/sangue , Estudos de Viabilidade , Feminino , Lactação , Análise dos Mínimos Quadrados , Fenótipo
14.
Pol J Vet Sci ; 22(3): 445-455, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31560465

RESUMO

Eye fluids (aqueous humour and vitreous humour) may be helpful in estimating ante-mortem blood levels, since some parameters measured in these fluids have proved to be stable or to change in a predictable way after death. This would help in diagnosing the cause of death in some diseases or to evaluate ante-mortem blood levels in certain animals not easy to handle or with difficult access. In order to establish reference values of some parameters in blood and eye fluids (aqueous humour and vitreous humour), as well as the possible correlation among these three different fluids, various minerals and electrolytes (Ca, P, Mg, K, Na, Fe, Cr, Co, Ni, Cu, Zn, Se and Mo) were measured in 15 four to five year-old Lidia bulls, all dying after a period of significant stress and major exertion. Plasmatic values of Mg and P were much greater than reported in the literature. In general, mineral plasmatic values were greater than those found in ocular fluids (aqueous and vitreous), while Na, K and Cr were similar in the three fluids. We have verified the existence of correlations in P, Co and Mo among the three fluids measured, and between Se of plasma and vitreous humour. But the most marked correlations were observed in Mo (plasma -aqueous humour, r = 0.893, plasma-vitreous humour, r = 0.945, HA -HV, r = 0.849), in P (plasma-vitreous humour, r = 0.726) and in Co (plasma-vitreous humour, r = 879).


Assuntos
Humor Aquoso/química , Bovinos/sangue , Bovinos/fisiologia , Minerais/sangue , Condicionamento Físico Animal , Corpo Vítreo/química , Animais , Masculino , Minerais/química
15.
Pol J Vet Sci ; 22(3): 541-548, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31560471

RESUMO

The Intrauterine fetal development process is complicated and affected by many regulating factors such as maternal nutritional status, transcription factors and adipokines. Adipokines are kinds of active substances secreted by adipose tissue, including more than 50 kinds of molecules. To explore the correlation between calf birth weights and adipokines including adiponectin, leptin, visfatin, and IGF-1 in cows venous and venous cord blood. Fifty-four healthy multiparous Chinese Holstein cows were used; in which, cows with a calf weight less than 40 kg were included in group A (n=9); those with a calf weight between 40 kg~45 kg were included in group B (n=25) and ≥45 kg were included in group C (n=20), venous blood and cord venous blood was collected. An ELISA kit was used to evaluate the concentration of adiponectin, leptin, visfatin, and IGF-1, correlations between index-index and index-calf birth weight were analysed. In both cows venous and cord venous blood, adiponectin, leptin, visfatin, and IGF-1 levels were significantly correlated with each other (p⟨0.01), and levels of these adipokines in venous blood were significantly higher than cord venous blood (p⟨0.01). Adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were positively correlated with calf birth weights, and significantly correlated with calf birth weights respectively (p⟨0.01). Our study showed that adiponectin, leptin, and IGF-1 were found in venous blood and cord venous blood, and adiponectin, leptin, and IGF-1 in venous and cord venous blood potentially inter-regulated each other; adiponectin, leptin, and IGF-1 in venous blood were not significantly correlated with calf birth weights, while adiponectin, leptin, visfatin, and IGF-1 in venous cord blood were significantly correlated with calf birth weights, respectively.


Assuntos
Adiponectina/sangue , Bovinos/sangue , Sangue Fetal , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Nicotinamida Fosforribosiltransferase/sangue , Animais , Animais Recém-Nascidos , Peso ao Nascer , Feminino , Masculino
16.
J Dairy Sci ; 102(11): 10564-10572, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477289

RESUMO

The loss-of-function mutation of the apolipoprotein (APO) B gene (APOB) in Holstein cattle accounts for increased losses in calves that are homozygous for this mutation. Heterozygous carriers of the APOB mutation are clinically healthy but show decreased concentrations of plasma cholesterol and lipoproteins. So far, the metabolic effects of the mutation have only been investigated in heterozygous calves, bulls, and nonlactating females. In high-yielding dairy cows, a marked decrease in cholesterol concentration in plasma during early lactation is part of the usual metabolic changes. Given the essential role of cholesterol in fatty acid and lipid metabolism, a specific effect of the APOB mutation on metabolism and performance in dairy cows is expected. Therefore, the aim of the present study was to investigate the effects of different APOB genotypes on metabolic parameters, hepatic metabolism, and lactation and reproductive performance. Twenty pairs of full siblings with similar age, performance, and calving were investigated. Both animals of each pair were kept on the same farm and consisted of a heterozygous carrier (CDC) and a noncarrier (CDF) of the APOB mutation associated with cholesterol deficiency. Blood samples were taken in early (25.5 ± 4.7 d in milk) and mid lactation (158.2 ± 11.1 d in milk; mean ± SD), and analyzed for nonesterified fatty acids, ß-hydroxybutyrate, glucose, insulin-like growth factor-1, aspartate aminotransferase and gamma-glutamyltransferase activity, total cholesterol, free cholesterol, triacylglycerols, high density lipoprotein-cholesterol, and phospholipids. The evaluation of milk production, milk gross composition, and lactation persistency was based on official Dairy Herd Improvement Association recordings. Cholesterol and lipoprotein concentrations were lower in CDC cows than in CDF cows in early and mid lactation. Metabolic parameters, triacylglycerol concentration in plasma, and lactation and reproductive performance did not differ between CDC cows and CDF cows. The low cholesterol concentrations associated with the APOB mutation in heterozygous carriers are not because of a primary deficiency of cholesterol at a cellular level, as the term "cholesterol deficiency" suggests, but rather a consequence of reduced capacity for its transport in circulation. Overall, the data of the present study suggest that, despite the presence of the APOB mutation, cholesterol is not limiting for animals' metabolic adaptation and performance in heterozygous Holstein cows.


Assuntos
Apolipoproteínas B/genética , Bovinos/genética , Colesterol/sangue , Mutação com Perda de Função , Ácido 3-Hidroxibutírico/sangue , Animais , Transporte Biológico , Glicemia/metabolismo , Bovinos/sangue , Colesterol/deficiência , HDL-Colesterol/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Lactação , Metabolismo dos Lipídeos , Fígado/metabolismo , Leite , Reprodução , Triglicerídeos/metabolismo
17.
J Dairy Sci ; 102(11): 10186-10201, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31477295

RESUMO

Metabolic status of dairy cows in early lactation can be evaluated using the concentrations of plasma ß-hydroxybutyrate (BHB), free fatty acids (FFA), glucose, insulin, and insulin-like growth factor 1 (IGF-1). These plasma metabolites and metabolic hormones, however, are difficult to measure on farm. Instead, easily obtained on-farm cow data, such as milk production traits, have the potential to predict metabolic status. Here we aimed (1) to investigate whether metabolic status of individual cows in early lactation could be clustered based on their plasma values and (2) to evaluate machine learning algorithms to predict metabolic status using on-farm cow data. Through lactation wk 1 to 7, plasma metabolites and metabolic hormones of 334 cows were measured weekly and used to cluster each cow into 1 of 3 clusters per week. The cluster with the greatest plasma BHB and FFA and the lowest plasma glucose, insulin, and IGF-1 was defined as poor metabolic status; the cluster with the lowest plasma BHB and FFA and the greatest plasma glucose, insulin, and IGF-1 was defined as good metabolic status; and the intermediate cluster was defined as average metabolic status. Most dairy cows were classified as having average or good metabolic status, and a limited number of cows had poor metabolic status (10-50 cows per lactation week). On-farm cow data, including dry period length, parity, milk production traits, and body weight, were used to predict good or average metabolic status with 8 machine learning algorithms. Random Forest (error rate ranging from 12.4 to 22.6%) and Support Vector Machine (SVM; error rate ranging from 12.4 to 20.9%) were the top 2 best-performing algorithms to predict metabolic status using on-farm cow data. Random Forest had a higher sensitivity (range: 67.8-82.9% during wk 1 to 7) and negative predictive value (range: 89.5-93.8%) but lower specificity (range: 76.7-88.5%) and positive predictive value (range: 58.1-78.4%) than SVM. In Random Forest, milk yield, fat yield, protein percentage, and lactose yield had important roles in prediction, but their rank of importance differed across lactation weeks. In conclusion, dairy cows could be clustered for metabolic status based on plasma metabolites and metabolic hormones. Moreover, on-farm cow data can predict cows in good or average metabolic status, with Random Forest and SVM performing best of all algorithms.


Assuntos
Bovinos/metabolismo , Metabolismo Energético , Aprendizado de Máquina , Leite/metabolismo , Ácido 3-Hidroxibutírico/sangue , Algoritmos , Animais , Glicemia/análise , Peso Corporal , Bovinos/sangue , Fazendas , Ácidos Graxos não Esterificados/sangue , Feminino , Insulina/sangue , Lactação , Leite/química , Paridade , Gravidez
18.
Anim Sci J ; 90(11): 1484-1494, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31498545

RESUMO

This study aimed to determine if a diet change from a mixed system to a confinement system affects the milk production and composition, behavior and blood biochemistry of dairy cows. Cows were assigned randomly to one of the two treatments: cows fed with TMR (total-mixed-ration) (confined) throughout the period group fed TMR (GTMR, n = 15) and cows that changed their diet from pasture plus TMR to exclusive TMR at 70 ± 14 DIM (GCHD, n = 15). GTMR cows produced more milk and greater lactose and protein yield before the change of diet than GCHD cows (p ≤ .01), but these differences disappeared after the change. GCHD cows decreased the frequency of rumination and lying from before to after the change (p ≤ .03), but in GTMR cows no changes were observed. After diet change, GCHD cows had lower frequency of rumination and lying than GTMR cows (p ≤ .02). Before the change, GCHD cows had greater NEFA (non esterified fatty acids) concentrations than GTMR cows (p = .002). Abrupt change from a mixed system to a confined system was favorable on blood biochemical and milk variables of dairy cows. However, in relation to behavior, the cows expressed difficulties to adapt quickly to the abrupt change of system.


Assuntos
Ração Animal , Comportamento Animal , Bovinos/fisiologia , Bovinos/psicologia , Dieta/veterinária , Herbivoria , Abrigo para Animais , Lactação/fisiologia , Adaptação Psicológica , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Bovinos/sangue , Ácidos Graxos não Esterificados/sangue , Feminino , Leite/química , Ruminação Digestiva/fisiologia
19.
J Anim Sci ; 97(11): 4371-4385, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31541251

RESUMO

Predominately Angus steers (n = 24; initial BW = 435 ± 28.3 kg) were used to evaluate non-coated (NC) and coated implants (CI) containing equal amounts of trenbolone acetate (TBA; 200 mg) and estradiol benzoate (EB; 28 mg) in finishing steers on sera metabolite responses, gene expression, and immunohistochemical analyses of the Longissimus muscle (LM). Performance data were analyzed as a randomized complete block design, and all other data were analyzed as repeated measures for a completely randomized design. Treatments were no implant (NI), NC (Synovex-PLUS; Zoetis, Parsippany, NJ), and CI (Synovex-One Feedlot) implant. There were 2 pen replicates per treatment (n = 4 steers/pen). LM biopsies, blood, and BW were collected before feeding on days 0, 14, 28, 56, 84, 112, and 133, with final BW being captured on day 140. Genes of interest were determined by RT-qPCR using two housekeeping genes. Sera was analyzed for estradiol-17ß (E2),17ß-trenbolone (TbOH), insulin-like growth factor 1 (IGF-I), NEFA, and urea-N (SUN). An α of 0.10 determined significance for performance and sera data; α of 0.05 was used for gene and histology data. No performance differences (P ≥ 0.10) were detected. An implant × day interaction (P ≤ 0.10) for E2, IGF-I, and SUN was detected; implants elevated (P ≤ 0.10) E2, 17ß-TbOH, and IGF-I; and decreased SUN across day of the study, meaning sera metabolites are not altered with time on feed. An implant × day interaction was detected for myogenic factor 5 (MYF-5) positive cells and proportions of MHCIIX. In LM, CI had greater (P < 0.10) IGF-I in LM over NI. CI increased (P < 0.05) G protein-coupled estrogen receptor 1 (GPER1) expression, as well as, GPER1 semi-quantitative scores over NI and NC. An implant × day interaction (P ≤ 0.05) for estrogen and androgen receptor-positive nuclei was detected; implants had increased (P ≤ 0.05) estrogen and androgen receptor-positive nuclei compared to NI. CIs increase genes associated with muscle tissue growth.


Assuntos
Anabolizantes/administração & dosagem , Bovinos/fisiologia , Estradiol/análogos & derivados , Esteroides/administração & dosagem , Acetato de Trembolona/administração & dosagem , Anabolizantes/sangue , Ração Animal , Animais , Bovinos/sangue , Dieta/veterinária , Implantes de Medicamento/administração & dosagem , Ingestão de Alimentos , Estradiol/administração & dosagem , Estradiol/sangue , Imuno-Histoquímica/veterinária , Fator de Crescimento Insulin-Like I/análise , Masculino , Músculo Esquelético/metabolismo , Distribuição Aleatória , Carne Vermelha/análise , Acetato de Trembolona/sangue
20.
J Dairy Sci ; 102(12): 11561-11585, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31548056

RESUMO

This study aimed to investigate the differences in the metabolic profiles in serum of dairy cows that were normal or overconditioned when dried off for elucidating the pathophysiological reasons for the increased health disturbances commonly associated with overconditioning. Fifteen weeks antepartum, 38 multiparous Holstein cows were allocated to either a high body condition (HBCS; n = 19) group or a normal body condition (NBCS; n = 19) group and were fed different diets until dry-off to amplify the difference. The groups were also stratified for comparable milk yields (NBCS: 10,361 ± 302 kg; HBCS: 10,315 ± 437 kg; mean ± standard deviation). At dry-off, the cows in the NBCS group (parity: 2.42 ± 1.84; body weight: 665 ± 64 kg) had a body condition score (BCS) <3.5 and backfat thickness (BFT) <1.2 cm, whereas the HBCS cows (parity: 3.37 ± 1.67; body weight: 720 ± 57 kg) had BCS >3.75 and BFT >1.4 cm. During the dry period and the subsequent lactation, both groups were fed identical diets but maintained the BCS and BFT differences. A targeted metabolomics (AbsoluteIDQ p180 kit, Biocrates Life Sciences AG, Innsbruck, Austria) approach was performed in serum samples collected on d -49, +3, +21, and +84 relative to calving for identifying and quantifying up to 188 metabolites from 6 different compound classes (acylcarnitines, AA, biogenic amines, glycerophospholipids, sphingolipids, and hexoses). The concentrations of 170 metabolites were above the limit of detection and could thus be used in this study. We used various machine learning (ML) algorithms (e.g., sequential minimal optimization, random forest, alternating decision tree, and naïve Bayes-updatable) to analyze the metabolome data sets. The performance of each algorithm was evaluated by a leave-one-out cross-validation method. The accuracy of classification by the ML algorithms was lowest on d 3 compared with the other time points. Various ML methods (partial least squares discriminant analysis, random forest, information gain ranking) were then performed to identify those metabolites that were contributing most significantly to discriminating the groups. On d 21 after parturition, 12 metabolites (acetylcarnitine, hexadecanoyl-carnitine, hydroxyhexadecenoyl-carnitine, octadecanoyl-carnitine, octadecenoyl-carnitine, hydroxybutyryl-carnitine, glycine, leucine, phosphatidylcholine-diacyl-C40:3, trans-4-hydroxyproline, carnosine, and creatinine) were identified in this way. Pathway enrichment analysis showed that branched-chain AA degradation (before calving) and mitochondrial ß-oxidation of long-chain fatty acids along with fatty acid metabolism, purine metabolism, and alanine metabolism (after calving) were significantly enriched in HBCS compared with NBCS cows. Our results deepen the insights into the phenotype related to overconditioning from the preceding lactation and the pathophysiological sequelae such as increased lipolysis and ketogenesis and decreased feed intake.


Assuntos
Bovinos/sangue , Dieta/veterinária , Aprendizado de Máquina , Metabolômica , Animais , Aminas Biogênicas , Peso Corporal , Metabolismo Energético , Feminino , Lactação , Leite/metabolismo , Paridade , Parto , Condicionamento Físico Animal , Gravidez
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA