THE EFFECT OF COMPOUND COMPOSITION AND SILAGE CHARACTERISTICS ON SILAGE INTAKE, FEEDING-BEHAVIOR, PRODUCTION OF MILK AND LIVE-WEIGHT CHANGE IN LACTATING DAIRY-COWS

An experiment was carried out to investigate the effects of compound composition and silage characteristics on silage intake, feeding behaviour and productive performance of dairy cows during the first 25 weeks of lactation. Over a period of 3 years, 36 lactating British Friesian cows (12 per year), in their third or later lactations, were divided into two groups. The cows in each group received either compound S, in which the principal energy source was cereal starch, or compound F containing a mixture of high quality digestible fibre. Cows given compound F ate 2.2 kg more silage dry matter per day (P < 0.05). The type of compound had no effect on the frequency of silage feeding and the time spent eating was significantly different only over weeks 10 to 25 of lactation (P < 0.05), with cows on compound F spending on average 20 min longer feeding per day. Cows on compound F produced 1.7 kg more milk per day than cows on compound S. Although there were no significant differences in the concentration of milk constituents, compound F was associated with higher yields of milk constituents. Significant differences were found between the years of experiment in the frequency of feeding (P < 0.05) and also in the concentration of milk protein and milk fat. There were no significant differences in the magnitude of live-weight change between treatments or year of experiment.