Effect of Concentrate Mixture on Rumen Microbial Activity in Male Goats across Different Breeds

Abstract

Twenty seven males of three goat breeds namely Toggenburg, German Alpine and Small East Africa were used in a factorial experimental design to determine the effect of supplementation on microbial performance. The concentrate mixture(CM) used for supplementing a basal diet of Napier grass(NG) was compounded from ground maize grain, sunflower seed cake, Mineral Salt and dairy premix. The corresponding basal die- tary treatments were designated at three levels of concentrate mixture (gms/day/goat) as follows; i) Control (C); (NG+0), ii) Low Plane (L); (NG+ 200) and (iii) High Plane (H); (NG+400). The experimental animals were randomly selected from a population of thirty six male goats of three breeds that were initially used during a digestibility trials. The pH and the ammonia nitrogen (N) of the ruminal liquor were inversely relat- ed to each other in control and pH being highest (P≤0.05) and N the lowest (P≤0.05). The pH and the Am- monia nitrogen of the rumen liqour was investigated at four set of hours namely 0, 3, 6 and 12 hours. The highest level of ruminal pH was observed at 0 hours before the concentrate mixture was offered. However the highest levels of Ammonia nitrogen in the rumen was observed after the concentrate diet was offered three hours. The pH level decreased three hours later after the concentrate mixture diet was offered. The Ammonia Nitrogen level decreased on a linear scale as time progressed except after three hours. The lowest Ammonia Nitrogen level was recorded after 12 hours of rumen liqour collection. There was significance difference in the pH among the three breeds and the three different levels of concentrate mixture. Low am- monia nitrogen production among the low plane dieters is attributed to low availability of soluble carbohy- drates resulting to low digestible energy production in the fermentation chambers (rumen) of ruminant. In- crease in level of concentrate mixture supplementation (P<0.05) affected the levels of microbial production of Ammonia and pH.