Cattle, sheep, and goat humoral immune responses against SARS-CoV-2.

Following the emergence of SARS-CoV-2 in late 2019, several species of domestic and wild animals have been found to be susceptible to SARS-CoV-2 infection through experimental inoculation and animal surveillance activities. Detection of SARS-CoV-2 specific antibodies in animals is an important surveillance tool since viral shedding in animals can only be detected for a short period of time. In this study, convenience serum samples were collected from 691 cattle, 698 sheep, and 707 goats from several regions in the United States, between 2019 and 2022.

Bison, Elk, and Other Captive Wildlife Species Humoral Immune Responses against SARS-CoV-2.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for COVID-19, has been found to infect various domestic and wild animal species. In this study, convenience serum samples from 575 bison, 180 elk, and 147 samples from various wildlife species collected between 2020 and 2023 from several regions in the United States were analyzed for the presence of SARS-CoV-2-specific antibodies. Two commercial ELISA assays based on the inhibition of the SARS-CoV-2 receptor-binding domain (sVNT) or the nucleocapsid protein (N-ELISA) of SARS-CoV-2 were used.

Effects of guanidinoacetic acid supplementation on nitrogen retention and methionine flux in cattle.

Creatine stores high-energy phosphate bonds in muscle and is synthesized in the liver through methylation of guanidinoacetic acid (GAA). Supplementation of GAA may therefore increase methyl group requirements, and this may affect methyl group utilization. Our experiment evaluated the metabolic responses of growing cattle to postruminal supplementation of GAA, in a model where methionine (Met) was deficient, with and without Met supplementation.

Effect of post-ruminal guanidinoacetic acid supplementation on creatine synthesis and plasma homocysteine concentrations in cattle.

Creatine stores high-energy phosphate bonds in muscle, which is critical for muscle activity. In animals, creatine is synthesized in the liver from guanidinoacetic acid (GAA) with methylation by S-adenosylmethionine. Because methyl groups are used for the conversion of GAA to creatine, methyl group deficiency may occur as a result of GAA supplementation.

Cow-specific risk factors for retained placenta, metritis and clinical mastitis in Holstein cows.

The objective of this study was to evaluate the association between cow-specific risk factors and the lactational incidence risks of retained placenta (RP), metritis (MET) and clinical mastitis (CM) in 57,301 dairy cows on 20 large dairy herds in Iran between January 2005 and June 2009. A multivariable logistic regression model was used to identify risk factors for MET, RP and CM and quantify their odds ratio (OR). The lactational incidences of MET, RP and CM were 8%, 5.

Evaluation of the potential effects of abortion on the productive performance of Iranian Holstein dairy cows.

Calving records from the Animal Breeding Center of Iran collected from January 1983 to December 2007 and comprising 1,163,594 Holstein calving events from 2552 herds were used to evaluate the potential effect of abortion occurrence on 305-day milk yield, milk fat yield, fat percentage of milk and milk protein yield in Iranian Holsteins. Statistical analyses of production traits were performed using a linear mixed model procedure. Normal-calved cows had greater 305-day milk production, fat yield and protein yield of milk than abortive-calved cows (P < 0.

Genetic relationship between milk urea nitrogen and reproductive performance in Holstein dairy cows.

The objective of this study was to describe the genetic and phenotypic relationship between milk urea nitrogen (MUN) and reproductive traits in Iranian Holstein dairy cows. Test-day MUN data obtained from 57 301 dairy cows on 20 large dairy herds in Iran between January 2005 and June 2009. Genetic parameters for MUN and reproductive traits were estimated with a five-trait model using ASREML program.

Bayesian estimates of genetic parameters for metritis, retained placenta, milk fever, and clinical mastitis in Holstein dairy cows via Gibbs sampling.

The objective of this study was to estimate heritability and genetic correlations between the liabilities of clinical mastitis (CM), milk fever (MF), metritis (MET), and retained placenta (RP) within the first three lactations of Holstein dairy cows. The records of 57,301 dairy cows from 20 large dairy herds in Iran between January 2005 and June 2009 were analysed with univariate and bivariate threshold animal models, using Gibbs sampling methodology. The final model included the fixed class effects of herd-year, season of calving, parity of dam, the linear covariate effect of age at calving, and the random direct genetic effect of animal.