T. Slavov, V. Radev, S. Tchobanova
Abstract. An experiment was conducted with 24 Pleven Blackhead yearling sheep in the experimental base of the Animal Physiology Unit, Faculty of Agriculture to Trakia University – Stara Zagora. The animals’ average weight at the beginning was 28.8 кg. The fattening period lasted 80 days, and sheep were weighed at 15-day intervals. Ruminal content samples were obtained post mortem. Sheep were divided into four groups of 6 animals each – one control and three experimental. The ration of the control group consisted of 800 g barley and 800 g meadow hay. The rations of experimental groups were supplemented with 20 g palm oil per 1 kg concentrate. The first experimental group received 800 g barley and 800 g meadow hay. The second experimental group was fed 800 g concentrate (barley and sunflower meal at a ratio of 1 kg barley and 200 g sunflower meal) plus 800 g meadow hay. The third experimental group was offered 800 g meadow hay and 800 g concentrate (consisting of 1 kg barley and 200 g sunflower expeller). The following parameters were determined: total infusorian counts, total volatile fatty acids content, ammonia concentrations and the body weight of animals. The effects of dietary palm oil supplementation in yearling sheep were analyzed. After addition of palm oil to the rations of the second experimental group, the total infusorian counts decreased statistically significant vs control and group I /p<0.001/. In experimental group III, the palm oil supplementation resulted in lower infusorian counts compared to each of other three groups /p<0.001/. Palm oil improved significantly the daily weight gain in the third experimental group compared to control sheep /p<0.05 /.