Seasonal variations in nutritional composition of different oak species in North-western Himalayas: significance for livestock feeding in high-altitude regions

The present study aims to evaluate the nutritional composition of leaf fodder from five major oak species (Quercus baloot, Q. dilatata, Q. glauca, Q. leucotrichophora and Q. semecarpifolia) across four seasons and assess their potential as fodder resources for livestock in temperate regions of the North-western Himalayas. Leaf samples were collected at 3-month intervals from four sites each in Shimla and Kinnaur districts, yielding 160 pooled leaf samples in total. Leaf samples were analysed via proximate analysis for dry matter, crude protein, ether extract, crude fibre, neutral detergent fibre (NDF), acid detergent fibre (ADF), nitrogen-free extract (NFE), ash, matter, calcium, and phosphorus. Results revealed significant (p < 0.05) seasonal and species-specific variations: dry matter ranged from 61.12 % to 65.05%, highest in Q. baloot across seasons; crude protein (9.28–10.54%) peaked in summer; ether extract (3.93–4.45%) and total ash (3.33–4.05%) rose with leaf maturation; crude fibre was highest in Q. baloot (40.82%); NDF and ADF peaked in winter, NFE in summer; calcium and phosphorus were highest in Q. leucotrichophora, both peaking in winter season. The findings highlight the importance of species selection and seasonal utilisation of these underexplored Quercus species, underscoring seasonal influences for optimised livestock management.