Abstract

Background:
Tithonia diversifolia is a high-protein forage plant, while fermented oil palm frond baglog, a by-product of mushroom cultivation, offers a sustainable fiber source for ruminant feeding. Combining these ingredients may improve nutrient balance, rumen fermentation, and growth performance in thin-tailed sheep.

Aim:
This study evaluated the effects of diets combining Tithonia diversifolia and fermented oil palm frond baglog on microbial protein synthesis, rumen fermentation characteristics, nutrient digestibility, and growth performance of thin-tailed sheep.

Methods:
Sixteen male thin-tailed sheep (10–12 months old; 15–20 kg) were allocated in a Completely Randomized Design with four dietary treatments and four replicates each: A = 40% concentrate + 60% Tithonia + 0% baglog; B = 40% concentrate + 40% Tithonia + 20% baglog; C = 40% concentrate + 30% Tithonia + 30% baglog; D = 40% concentrate + 20% Tithonia + 40% baglog. Parameters measured included purine derivatives (allantoin, uric acid, xanthine, hypoxanthine), microbial nitrogen supply, rumen pH, NH₃-N, volatile fatty acids (VFA), nutrient digestibility (dry matter, organic matter, crude fat, total digestible nutrients), feed efficiency, and average daily gain (ADG).

Results:
No significant differences were observed among treatments for microbial protein synthesis parameters. The D diet (20% Tithonia, 40% baglog) yielded the highest values for total purine derivatives (23.88 mM/day), allantoin (20.31 mM/day), microbial N supply (26.37 mM/day), dry matter digestibility (87.13%), organic matter digestibility (93.77%), crude fat digestibility (98.31%), feed efficiency (0.139%), and ADG (81.25 g/day). Rumen pH ranged from 7.09–7.22, NH₃-N from 42.36–43.50 mg/100 ml, and VFA from 79.89–92.78 mM.

Conclusion:
A diet containing 20% Tithonia diversifolia and 40% fermented oil palm frond baglog optimizes nutrient digestibility, microbial nitrogen supply, and growth performance in thin-tailed sheep without negatively affecting rumen fermentation balance. This combination represents a sustainable feeding strategy for improving small ruminant productivity.

Key words: Baglog; Microbial protein synthesis; Thin-tailed sheep; Tithonia.