Effect of a different concentrate-forage sequence on digesta passage rate, faeces traits and milk features of dairy cows.

To ascertain the effects of a different feed sequence, which could modify digestion rate and sites as well as metabolic - endocrine status and milk features, 6 lactating dairy cows have received the same diet with a different time of concentrate administration when close to the two daily forage meals: 30'before or 60' after them. Cows were tied in a barn with controlled temperature, humidity and light, individually fed and monitored for: daily dry matter intake, milk yield and its features at 2 milkings, concentrate passage rate and faecal traits. The results have showed that DMI, feeding behaviour, milk yield and milk features were not significantly affected (except fat content, increased when forage was supplied as first feed). The digesta passage rate was also different: concentrate escaped more rapidly from the rumen when fed before forage or 4 hours after them. This effect has not modified the faeces, but some endocrine and/or metabolic changes can be hypothesized, because milk fat content was increased when concentrate was supplied after forage.