Supplementation with Fish Oil Improves Meat Fatty Acid Profile although Impairs Growth Performance of Early Weaned Rabbits

SIMPLE SUMMARY: Early weaning is a practice commonly applied in rabbit production despite its possible detrimental consequences on production, as it negatively affects the welfare of young rabbits that are highly susceptible to digestive disturbances. The inclusion of long-chain n-3 polyunsaturated fatty acids (PUFA) in the mother’s diet during the suckling period can bring substantial benefits to the kits, as PUFA are involved in the development of the immune response in early weaned animals and could reduce morbidity and mortality during the fattening period. In this study, we observed that including fish oil (containing PUFA) in the diet of early weaned rabbits can reduce their morbidity and enhance the content of beneficial long-chain n-3 fatty acids in rabbit meat and fat, but it also slightly reduces their growth. ABSTRACT: Our objective was to analyze the influence of replacing lard (control) with fish oil (FO) rich in long-chain n-3 polyunsaturated fatty acids in the diet of rabbits weaned at 25 days of age on their growth performance, meat quality, cecal fermentation, and ileal morphology. Twenty-four litters (12 control and 12 FO) of nine kits each were fed the experimental diets from weaning (25 days) until slaughter at 60 days of age. Half of the litters (six per diet) were used to monitor productive performance, carcass characteristics, and ileal morphology, and cecal fermentation was assessed in the rest of litters. Diet had no influence on feed intake, meat color, and pH or cecal fermentation, but FO-fed rabbits had lower (p ≤ 0.049) average daily gain, chilled carcass weight, and perirenal fat than control rabbits. Fish oil inclusion in the diet resulted in lower morbidity (5.56% vs. 20.4%; p = 0.019) and a healthier fatty acid profile with lower (p < 0.001) n-6/n-3 ratios in both muscle and perirenal fat. In summary, the inclusion of FO in the diet of early weaned rabbits improved the fatty acid profile of rabbit meat and fat and decreased the morbidity, but growth performance was slightly reduced.