FRACTIONAL OUTFLOW OF SOYBEAN-MEAL FROM THE RUMEN, WATER-INTAKE AND RUMINAL FERMENTATION PATTERN IN SHEEP AND GOATS AT DIFFERENT SEASONS AND AGE-GROUPS

The effect of age (5 or 8 months old) on the fractional outflow rate ( FOR) of chromium (Cr)-treated soya from the rumen of Chios lambs and D amascus kids (five animals per age group per species) was studied in T rial 1. The effect of season (spring, summer, winter) on the FOR of Cr -treated soybean meal (SBM) from the rumen, water consumption and rumi nal fermentation pattern was determined in Trial 2 using four dry, mat ure, rumen fistulated Chios ewes and four Damascus goats per season. T here was no difference in feed dry matter (DM) intake per kg(0.75) bod y weight (BW) between species in both trials. In Trial 1, neither anim al species () nor age () affected FOR of Cr-treated SBM from the rumen . Moreover, there was no effect (P > 0.1) of animal species and season on ruminal pH, NH3-N and acetate molar proportion (Trial 2). Season a ffected propionate (P < 0.007) and butyrate (P < 0.005) molar proporti ons and water consumption. Water consumption was greater (P < 0.001) i n summer than in winter and spring, but not different between spring a nd winter. Ewes consumed more water (P < 0.05) and had greater butyrat e molar proportion (P < 0.005) and total volatile fatty acid concentra tion (P < 0.003) than goats. DM degradability of straw incubated in th e rumen for 48 h was similar in ewes and goats, and was not affected b y season. The FOR of Cr-treated SBM from the rumen was faster (P < 0.0 22) in goats than in ewes. Season had only a small and non-significant (P > 0.1) effect on FOR. Due to differences of results among trials, it does not seem advisable to propose, at least at present, different FOR for sheep and goats, and for different seasons of the year and/or between growing lambs and kids of varying age.