The supplementation of maize silage for an autumn-calving dairy herd

SUMMARY Thirty-nine British Friesian lactating cows were used to study the effects on milk production of supplementation of maize silage offered ad libitum during two 3-hr periods each day. During weeks 11 to 24 of lactation a comparison was made of (i) no supplement, (ii) 183 g/day of a mixture (2: 1) of urea: urea phosphate, (iii) 5 kg/day of barley plus 183 g/day of the urea: urea phosphate mixture, (iv) 7 kg/day of dried grass and (v) 10 kg/day of dried grass. The corresponding treatment mean values were: milk yield (kg/day), 10·0, 9·9, 13·4, 15·1, 16·8; fat content (%), 3·43, 3·80, 3·98, 3·92, 3·61; solids-not-fat content (%), 7·95, 8·03, 8·45, 8·51, 8·49; energy intake (MJ/day), 71·2, 76·9, 130·3, 132·7, 138·6; intake of dry matter as maize silage (kg/cow per day), 7·1, 7·7, 8·3, 7·7, 6·5. With the exception of fat content, the differences between treatments 1 and 2 were not significant but the values for these two treatments were significantly lower than those for the other three treatments.