Supplementation of dairy cows offered freshly cut herbage ad libitum with starchy concentrates based on barley or fibrous concentrates based on unmolassed sugar beet pulp and wheat bran
1991
Spoerndly, E. (Sveriges Lantbruksuniv., Uppsala (Sweden). Inst. foer Husdjurens Utfodring och Vaard)
An experiment was conducted with dairy cows to examine the effects of a starchy and a fibrous concentrate. The starchy concentrate (S) was composed of barely and soybean meal in proportions 80/20, and the fibrous concentrate (F) of unmolassed sugar beet pulp, wheat bran and soybean meal in proportions 60/20/20. The concentrates were fed at two levels of supplementation, 4 and 7 kg cow-1 day-1. A fifth treatment with no concentrates (0) was included. All cows were offered freshly cut herbage ad libitum and 2.4 kg hay per day. The experiment was conducted with 20 Swedish red and white cows during the second half of lactation. The experimental design was an incomplete Latin square with three periods, each period lasting 18 days. Roughage intake was 16.5, 14.7, 14.4, 13.0 and 12.5 kg DM and milk yield was 20.2, 21.8, 21.0,23.1 and 22.8 kg ECM with treatments 0, 4S, 4F, 7S and 7F. No significant differences in roughage intake or milk yield were obtained between concentrates S and F but supplementation with S gave a small increase in milk fat content. Increasing amounts of concentrate S, up to 7 kg, increased milk protein content, while the treatment with no concentrates lowered protein content in milk.
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