Effects of green oak acorn (<i>Quercus ilex</i>) intake on nutrient digestibility, lamb growth, and carcass and non-carcass characteristics

Abstract

Abstract. The green oak (Quercus ilex) plays an important role in forest ecology when oaks are the dominant species or are plentiful. The use of acorns as an alternative to barley for livestock feeding can be beneficial for breeders. The aim of this study was the evaluation of the acorn intake by lambs in two stages, suckling and fattening, on growth, diet digestibility, carcass and non-carcass characteristics. For this, 32 lambs were used. During the suckling period, 16 lambs were reared on range pasture, supplied by barley (S-Ba), the other 16 on forest pasture and supplied by acorns (S-Ac). During the fattening period, lambs were assigned to concentrate based either on barley (F-Ba) or acorn (F-Ac) resulting in eight animals per suckling treatment per fattening treatment. The feed intake, diet digestibility and lamb growth were recorded. At 90 d of fattening, all animals were slaughtered and carcass traits studied. The main results show that the incorporation of acorn in concentrate was without effect on digestibility of organic matter, crud protein and neutral detergent fibre. The nitrogen balance was positive for animals fed barley concentrate or acorn one (>8 g d−1). The lamb growth rates and slaughter body weight were not affected by acorn incorporation in both phases (p>0.05). Consequently, the carcass weights and carcass yields were similar. The F-Ac and S-Ac lambs had relatively heavier liver than F-Ba and S-Ba. The carcass composition in cutting pieces and that in tissues (muscle, fat and bone) was similar for all groups. These results suggest that acorns could replace partially conventional feedstuffs as concentrate without affecting animal performance and carcass quality.