Use of almond hulls in lamb diets - Effects on growth performance and carcass and meat quality

The effect of partial replacement of cereals by increasing levels of almond hulls (AH) was tested in twenty-four lambs distributed into three dietary treatments: 1) diet without replacement of cereals with AH (0AH); 2) diet with replacement of cereals with 9% of AH (9AH); and 3) diet with replacement of cereals with 18% of AH (18AH). All diets included 40% dehydrated lucerne and 5% soybean oil. Dry matter intake, growth performance, feed costs, carcass traits, meat quality, and lipid oxidative stability of raw and cooked meat during refrigerated storage were evaluated. Replacing part of the cereal with AH up to 18% did not affect the average daily gain but increased quadratically the feed conversion ratio and tended to decrease linearly the slaughter live weight. Diet cost per kg live weight gain was affected quadratically, with similar feed costs in 0AH and 18AH diets. The carcass and meat quality parameters were not affected by diet, except meat shear force that linearly reduced with the inclusion of AH in diets, meat flavour acceptability that showed lower values in 9AH diet, and lipid stability. Lipid oxidation increased in raw and cooked meat during storage, but the 18AH diet resulted in lower lipid oxidation in cooked meat than the other diets. Replacing part of the cereal with AH up to 18% in diets composed of 40% forage shown to be a dietary strategy applicable to fattening lamb, allowing high productive performances without relevant impact on feed costs, and improving lipid stability of cooked meat.