Nutritive valve of oak (Quercus spp.) leaves

Abstract

The nutritive values of browse leaves from five oak species, namely Quercus branti, Quercus coccifera, Quercus cercis, Quercus libari and Quercus infectaria were evaluated based on their chemical composition and gas production. Organic matter (OM) contents ranged from 929.8 to 952.1 g/kg DM; CP from 36.2 to 83.5 g/kg DM with Q. coccifera showing the lowest protein content. Crude fibre (CF) contents ranged from 305.9 to 509.2 g/kg DM. Gas production levels after 12 h for Q. branti and Q. libari were higher (P < 0.001) than for other oak species. The rank order in terms of gas production performance was as follows: Q. libari = Q. branti > Q. infecteria > Q. coccifera > Q. cercis. Strong correlation was observed between gas production and crude fibre content of oak leaves. Crude fibre and tannin contents of oak leaves negatively correlated with gas production. Oak leaves from Q. branti and Q. libari may have a high potential nutritive value for small ruminant animals in terms of rumen and whole tract digestion. The variation in gas production reported in this study could result in differential intakes of oak leaves when given as sole diets, because gas production is negatively correlated with the level of crude fibre of oak leaves.