Citrus pulp and wheat straw silage as an ingredient in lamb diets: effectson growth and carcass and meat quality

Twenty "Merinizzata Italiana" lambs were introduced to two experimental die ts. Ten animals (five males and five females, control group) received the t raditional diet that is supplied by farmers in southern Italy, which compri sed of oat hay ad libitum and commercial concentrate. The second group (the same number of lambs, silage group) received citrus pulp and wheat straw s ilage ad libitum and 70% of the commercial concentrate supplied to the cont rol group. The animals were slaughtered after 80 days of feeding and carcas s and some meat quality parameters were measured. No differences were obser ved for live weight between treatments, and carcass weights were similar fo r the two diets, but with obvious differences between sexes. Animals on sil age produced carcasses with a better muscular conformation and with a lower fatness score (P < 0.05). Subcutaneous fat colour was influenced by sex, b eing lighter in the female carcasses (P < 0.05). Dissection Of different an atomical parts showed a higher percentage of lean and a lower proportion of fat in silage samples compared to control ones. Ultimate pH was highly aff ected by sex being higher in the samples from male lambs (P < 0.01), but wa s unaffected by diet treatment. Diet tended to affect meat shear force valu e which was lower in the silage samples, although, samples from all the ani mals were extremely tender. Meat from silage samples had a higher water con tent (P < 0.05). Overall, in our experimental conditions, the use of citrus pulp silage seemed to be economically convenient for producing animals wit h substantially unmodified carcass and meat quality characteristics. (C) 20 01 Elsevier Science B.V. All rights reserved.