The rate of fermentation and the in vitro degradability of palm kernel meal from Elaeis guineensis Jacq. when included in sheep diets.

Objective: Measure the biogas production, degradability and fermentation kinetics of diets containing different levels of palm kernel meal. Design/methodology/approach: The treatments were 0%, 15%, 30% and 45% palm kernel meal (PKM). The nutritional and chemical content was determined, including dry matter, total protein, ethereal extract; ash; neutral and acid detergent fiber fractions. Culture vials (120 ml) were used, to which 0.5 g of the experimental diets were added, followed by 50 ml of rumen inoculum under continuous CO₂ flow. The vials were then sealed with neoprene plugs and aluminum rings and incubated at 39 °C for 72 hours. Biogas displacement was measured at 3, 6, 9, 12, 24, 48 and 72 hours. Results: The treatment that produced less biogas (p < 0.05) at 6 and 9 h of incubation was the one with 45% inclusion of palm kernel meal. The diet with 45% inclusion of PKM presented the lowest maximum gas volume (291.35) of the four treatments evaluated (p<0.05). Study limitations/implications: Results may vary when using higher and lower PKM inclusions in experimental diets, or when combining them with one or two cereals. The fermentative and digestible behavior of the ingredients may also change. Findings/conclusions: Under in vitro conditions, the inclusion of 45% palm kernel meal reduces biogas production. PKM represents an alternative use for inclusion in diets.