Feeding hay-based diets deficient in protein to dairy cows during early lactation
1984
Bartsch, B.D. | Wickes, R.B. (South Australian Dept. of Agriculture, Adelaide. Northfield Research Centre)
Mean estimated intakes of hay DM during the first 12 weeks of lactation were 15.1, 14.8 and 12.3 kg per cow per day for cows fed diets of moderate (M) (14.1 percent) moderate-low (ML) (11.7 percent) and low (L) (9.2 percent) protein content respectively. Significant differences in liveweight between groups were recorded during the first 12 weeks of lactation. The mean daily yields of milk during this time were higher for cows on M or ML diets (22.1 l) than those on the L diet (16.0 l). Milk yields for weeks 13-24 and 25-36 did not differ between treatment groups. Milk composition did not differ between treatment groups in any 12-week period. Cows fed L diets were less efficient in the use of feed or body reserves for milk production than those fed ML or M diets. Economic data indicate that it is currently profitable to ensure that the protein content of diets fed during early lactation is at least 14 percent of DM irrespective of the likely regime over the remainder of the lactation.
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