An examination of the effect of concentrate energy source on milk production of dairy cows offered grass silages with differing intake characteristics

Considerable progress has been made recently at this Institute in improving the accuracy of prediction of silage intake when offered as the sole diet. However in most farm situations, silage is usually supplemented with varying levels and types of concentrate when offered to dairy cattle. The aim of the present study was to examine the effects of concentrate energy source on the voluntary food intake and milk yield and composition of lactating dairy cattle when offered a diverse range of grass silages.A total of five grass silages were used in the study, silages A, B and D were produced from primary regrowths, while silages C and E were produced from second regrowths of perennial ryegrass swards. Silages A, B, C, D and E were ensiled after 48, 24, 0, 0 and 24 hour wilting periods. Silages A and C were ensiled untreated, B and D treated with an inoculant, and silage E treated with a formic acid based additive.