Exploring the impacts of fescue toxicosis on the pulmonary arterial pressure of angus cows.

Vasoconstriction of peripheral blood vessels is one of the hallmark symptoms of fescue toxicosis in cattle. Thus, it was hypothesized that exposure to ergot alkaloids would increase the pulmonary arterial pressure (PAP). The objectives of this study were to examine the relationship between PAP and different physiological parameters of cows grazing either endophyte-infected (EI) or novel-endophyte (EN) fescue, then evaluate changes in PAP and other physiological measurements in cows exposed to EI pastures and deemed as susceptible or tolerant based on animal performance.

Effects of endophyte-infected tall fescue seed and protein supplementation on stocker steers: I. Growth performance and hemodynamic responses.

Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue and is detrimental to growth and performance. Recent research has shown that supplementing protein has the potential to enhance growth performance in weaned steers. Therefore, the objective of this study was to evaluate the effect of supplemental CP on physiological parameters in stocker steers experiencing fescue toxicosis.

Effects of endophyte-infected tall fescue seed and protein supplementation on stocker steers: II. Adaptive and innate immune function.

Fescue toxicosis is a multifaceted syndrome common in cattle grazing endophyte-infected tall fescue that affects performance; however, little information is available pertaining to its effects on immunity. Recently, it has been shown that supplemental CP can improve performance in weaned steers postvaccination. Thus, the objective of this study was to evaluate the effect of supplemental CP on innate and adaptive immune responses in stocker steers chronically exposed to ergovaline.

Effects of dietary vitamin A content on antibody responses of feedlot calves inoculated intramuscularly with an inactivated bovine coronavirus vaccine.

Objective: To investigate effects of low dietary vitamin A content on antibody responses in feedlot calves inoculated with an inactivated bovine coronavirus (BCoV) vaccine.

Animals: 40 feedlot calves.

Procedures: Calves were fed diets containing high (3,300 U/kg) or low (1,100 U/kg) amounts of vitamin A beginning on the day of arrival at a feedlot (day 0) and continuing daily until the end of the study (day 140).