Effect of pre-treated almond by-products at different doses of fibrolytic enzyme on nutrition value, ruminal fermentation and enteric methane emission

Abstract Almond’s by-product is available in large quantities all over the world. However, little information is available about their feed value. The aim of this research was to determine their nutritional value and investigate the effect of pre-treating with exogenous fibrolytic enzymes (EFE) at 0, 1, 2, and 4 µL/ g DM.The result showed that the almond shell is a fibrous by-product with low energy value. The pre-treatment with high doses of EFE hydrolyses part of their cellulose and hemicellulose, improved their fermentation, digestibility and energy value. In addition, it improved protein produced by the ruminal microbiota and volatile fatty acids. This improvement is coupled with the reduction of methane emission. Almond teguments are rich in fibre and have high energy value due to their high fat content. A high content of condensed tannins has been detected in this by-product. The pre-treatments with EFE did not modify their fibre composition and nutritional value. Almond hulls have a high energy value due to their high non-fiber-carbohydrates content. It has moderate fibre compounds and high condensed tannins. The pre-treatment with EFE has no effect on their fibre composition. However, at the low dose, it improves their fermentation, digestion and protein produced by ruminal microbes and at the high dose it has an unharmful effect.This study can encourage farmers to use almond by-product as an alternative feed for ruminants. EFE is good strategy to improve nutritional value of almond by-product, reduce energy loss and protect the environment against global warming