INFLUENCE OF THE COMPOSITION OF FEEDING DURING THE DRY PERIOD ON THE REPRODUCTIVE-PERFORMANCE AND MILK-PRODUCTION IN ISRAELI-HOLSTEIN COWS

In each for of kibbutzim herds located in Israel the dry cows were divided in two feeding groups. The experimental group, in totally 266 cows, obtained only oat, barley or wheat hay ad libitum, whereas the control group (n = 253) was fed additionally mix or silage up to four kg dry matter. The cows in the control group responded in the following lactation with a 1.3 kg higher average FCM per day (p = 0.02) and with a 1.7 kg higher maximum FCM (p = 0.01) in comparison to the experimental group. The differences between the experimental and control group in A. I.-parameters days open, conception rate on first insemination and percent problem cows were rather small. However, the frequency of retained placenta and ovary cysts was significantly (p < 0.05) higher in the control group than in the experimental group. In one herd the influence of body condition between the end of lactation, dry period and 50-80 days p.p. as well as the change of body weight between the end of lactation and calving on milk production and fertility could be evaluated. A decrease of one body condition score unit between the dry period and 50-80 days p.p. was associated with an increase of FCM by 2.01 kg (p < 0.01), a decrease of the conception rate by 21 % (p < 0.05) and an elongation of the days open by 23.6 days (p < 0.01). The results show that a supplementation of grain hay in dry period feeding with mix or silages can be recommended because the milk production in following lactation increases and the fertility results are similar in both, the control group and experimental group.