Macronutrient-based assessment of fibre source quality in lowland and highland smallholder dairy cattle farms

Dairy cattle require high-quality fibre sources to support their milk production. Macronutrients, including ash, crude protein, ether extract, crude fibre (neutral detergent fibre, acid detergent fibre, and hemicellulose), nitrogen-free extract, and total digestible nutrients can be used to evaluate the quality of fibre sources. Altitude may influence the macronutrient composition of fibre sources due to microclimatic differences between lowland and highland areas. This study aimed to analyze the differences in fibre source quality used by dairy farmers in lowland and highland regions. Fibre source samples were collected from lowland farms (Bogor) and highland farms (Pangalengan). Fibre source samples were analyzed for proximate composition and fibre fraction (% DM) using NIRS. Group means were compared using an independent t-test. The results showed that crude protein levels in highland fibre sources were significantly higher (p<0.05), whereas crude fibre levels were significantly lower (p<0.05) compared with those in lowland areas. The NDF, ADF, and hemicellulose fractions in highland fibre sources were also significantly lower (p<0.05) than those in the lowland fibre sources. Based on their macronutrient composition, highland fibre sources exhibit better nutritional quality. These findings underscore the need to account for altitude-driven variation in fibre source nutritional quality in precision ration formulation.