Two concentrate protein levels and two supplementation rates for mid-lactating cows
1988
Perez, J.A.
In vitro dry matter and organic matter digestibility of the experimental diets of lactating cows ranged from 58.11 to 58.55%, and 50.14 to 51.95%, respectively. No significant differences were obtained among treatment means. Increasing the crude protein content of the concentrate from 15.5 to 18.6% increased significantly (P0.05) milk protein, blood serum protein, blood urea nitrogen, and dry matter intake as percent body weight. Increasing the rate of concentrate feeding from 1:2.5 to 1.2 increased significantly (P0.05) milk protein, blood serum protein, and blood urea nitrogen with a corresponding reduction (P.05) in percent butterfat. Milk yield and 4% FCM were not significantly affected by the two protein levels and two feeding rates. No significant interactions were observed between protein content and feeding rate on the productive parameters studied except for milk total solids content. All the cows lost weight during the experimental period. No significant differences were obtained in mean weight changes, feed efficiency and income-over-feed cost.
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