The impact of ferulate-esterase inoculation of grass silage on dry matter intake, milk yield, fecal composition and rumen fill of dairy cows

Abstract

A feeding experiment was carried out to test the effect of a ferulate esterase (11GFT) treatment of grass silage on performance and feces characteristics of dairy cows. The experiment contained 4 periods. In periods 1 and 3,a herd of approximately 70 dairy cows received a diet containing control silage, in periods 2 and 4, cows were fed diets containing 11GFT treated silage. Feed intake and milk yield were recorded. A constant group of 49 cows was scored at the end of each period cows for body condition, rumen fill, fecal consistency and fecal undigested particles. Fecal samples were taken at the end of each period from 4 cows which were the same during the whole experiment and fecal samples were analyzed for DM, NDF-concentration, digestibility of fecal-NDF and a simple wet sieving analysis was carried out. No effects of 11GFT on cow performance, rumen fill and fecal scores and fecal composition were observed, probably because other dietary factors were not constant during the experiment. To investigate the relationship between fecal composition and cow scores also another 15 fecal samples were taken during the experiment and together these 31 fecal samples were used to determine relationships between score results and analytical results. A significant positive correlation (r2 =.34) was found between rumen fill and digestibility of fecal-NDF. % Fiber after wet sieving was significantly correlated with fecal NDF-concentration (r2 = .48). Therefore rumen fill score and wet sieving may be useful to get an indication about NDF-digestion for animal nutritionists and veterinarians. A negative correlation between score for fecal undigested particles and fecal consistency score and fecal DM was found, but this score was not related to sieve results or fecal NDF-parameters.