Effects of high protein yeast with oil palm frond on feed utilization and blood chemical of Boer crossbred goats

This study aimed to investigate the effects of high-protein yeast combined with oil palm leaves on crossbred goats. Twelve goats with similar ages and average weights ranging 18 ± 1.5 kg were assigned to three independent experimental groups. Treatment 1 served as the control group (fresh Napier grass), treatment 2 received yeast-fermented oil palm leaves, and treatment 3 received yeast-fermented Napier grass, all for a duration of 90 days. The chemical composition of the yeast-fermented oil palm leaves showed higher crude protein content (10.84%) compared to yeast-fermented Napier grass and normal Napier grass (6.62% and 2.52%, respectively). Regarding feed intake, treatment 2 exhibited the highest consumption, with no significant statistical difference compared to the control group (p > 0.05), consuming the highest amount of feed (0.67 kg/day). Digestibility coefficients of organic matter did not significantly differ among treatments (58.34, 58.04, and 64.14, respectively) (p > 0.05). However, yeast supplementation significantly increased the digestibility of dry matter, crude protein, NDF fiber, and ADF fiber (p < 0.05). Yeast supplementation did not affect rumen pH and temperature, however, it enhanced the production of propionic and butyric acids in treatment 3 (14.43 and 9.04 millimoles per liter, respectively). Regarding blood chemistry, significant differences were observed in hemoglobin, hematocrit, red blood cell count, red blood cell distribution width, and blood urea nitrogen levels (p < 0.05). In conclusion, the use of yeast to improve the quality of oil palm leaves appears promising for enhancing animal nutrition. Furthermore, it represents a valuable agricultural application of oil palm by-products, particularly in the southern region, leading to increased nutritional benefits for livestock.