EFFECT OF LEVEL OF CONCENTRATE FEEDING AND ADDITION OF MONENSIN ON RUMEN FERMENTATION CHARACTERISTICS IN AWASSI LAMBS

Abstract

This study was conducted to investigate the effect of level of concentrate feeding and addition of monensin on fermentation characteristics of Awassi lambs. 16 Awassi male lambs were used with 4-6 months of age and mean initial weight of 21.27 kg. concentrate diet was offered at 2 levels (2.5 and 3% of BW) with or without addition of monensin at rate 30 mg/kg DM, ground wheat straw was offered ad libitum. Results showed that increasing level of concentrate increased (P<0.01) NH3-N concentration from 6.59 to 7.13 mg/100 ml without affecting TVFA concentration which was significantly decreased (P<0.01) from 14.14 to 12.10 mmol/100 ml as a result of addition of monensin at rate of 30 mg/kg DM. Despite of slight increase, pH values were not significantly affected by both factors. Concentrations of NH3-N and TVFA showed significant response (P<0.01) to the interaction effect between those two factors. In the study of diurnal changes, rumen fermentation characteristics showed an expected responses to the time of withdrawing rumen fluid samples from lambs.