Étude des variations biochimiques du lait et du sang chez les vaches laitières en fonction de l’alimentation.

Abstract

Our study has as main objective to establish a biochemical profile of blood and milk with different dietary intake (dry, early lactation). To make usual values available in the hand of veterinary practitioners so they can use them as an early diagnostic tool. A second objective was to determine the relationship between dietary and quality of milk. This research was conducted on 20 Holstein cows, aged 3 to 7 years, clinically healthy, multiparous from two dairy farms in the province of Constantine. The blood of 15 days interval samples were conducted during the period from the beginning of drying up until 3rd month of lactation. These samples have concerned some blood parameters (glucose, triglycerides, cholesterol, total protein, albumin, urea, creatinine, ALT, AST, calcium and phosohore). A milk monthly interval sampling was carried out during the first months of lactation. These relate to the determination of certain biochemical parameters "" milk protein, lactose"" and the analysis of some physicochemical parameters “acidity, density, pH”. Proteinemia, créatinimie and plasma ALT showed significant variation (p < 0.05) between the two farms of the study. The triglycédérimie, the chlestérolémie, the protéinimie, uremia, crétinimié, serum calcium, plasma ALT activity and AST, the rate of protein substances and lactose rate showed significant variation across different stages of the study. While blood sugar, serum albumin, serum phosphate, acidity, density, pH, and the fat rate showed no significant variation. The results obtained on the basis of the parameters indicate that the biochemistry of milk and blood may be an early detection tool of dietary errors.