Nitrogenous constituents in plasma of foals weaned at three, four or six months of age

A study was conducted to measure the nitrogenous constituents in the blood of foals weaned at 3, 4 or 6 months of age (four foals per weaning age).Jugular blood was sampled from one week prior to weaning until one month post-weaning, and was analyzed for total protein, albumin, creatinine, urea Nitrogen and free amino acid content. Results indicated that the concentrations of most of the constituents in the blood of foals were not altered by the age of weaning, however, free amino acids decreased as age at weaning increased and creatinine was significantly higher in foals weaned at 6 months of age. Plasma creatinine, lysine and methionine levels generally decreased between pre-weaning and one month post-weaning. These data establish baseline values for blood nitrogenous constituents in foals at weaning.