'I SOME DIETARY FACTORS AFFECTING RUMEN ACTIVITY AND MICROBIAL PROTEIN SYNTHESIS

Abstract

Four rumen fistulated Ossimi rams were used in 4 x 4 latin square with 2 x 2 factorial arrangement, to investigate the effect of variying levels of crude protein and crude fiber in the diet on digestibility, nitrogen balance, some rumen fermentation parameters (pH, ammonia-nitrogen, total volatile fatty acids, rate of solid and fluid passage from the rumen and microbial protein synthesis.

Rations were formulated and pelleted to include four different levels of crude protein and crude fiber i.e,high protein low fiber (17%, 13%, HPLF), high protein high fiber (17%, 21%, HPHF), low protein low fiber (13%, 17% LPLF) and low protein high fiber (13%, 21%, LPHF).

Feeding of rations, HPLF, HPHF, LPLF and LPHF

respectively resulted in :

1- Both low fiber diets either with high - or low protein had significanly (P < 0.05) higher digestion coefficient of DM, OM and NFE.

2- Dietary crude protein, with low or high fiber contents significantly improved the digestibility of CP and EE, while it improved the digestibility of CF with high fiber only.

3- Digestibility values were : CP, 79.34, 79.89, 73.04 and 71.63; CF, 52.78, 60.6, 51.62 and 54.24 respectively.

4- The highest NB was found with sheep fed HPLF diet (10.93 g/d) followed by those fed HPHF (8.47 g/d) and LPLF (7.93