Improving body composition in broiler chicks through the early life diet

The poultry industry relies heavily on the efficient growth performance of broilers to provide quality breast meat at a low cost to meet consumer demand. However, high efficiency of broilers is also related to the occurrence and severity of skeletal muscle abnormalities like wooden breast. This study investigated the efficacy of incorporating long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), into the diets of hens and their offspring on altering the causative features of wooden breast. Early exposure to these fatty acids in broilers has shown to reduce adiposity, and may address excess adipogenesis seen in wooden breast. Physical characteristics of weight gain and relative breast weight were measured to confirm that fish oil did not compromise growth. Histological analysis of the breast showed that the perinatal fish oil diet promoted growth of larger muscle fibers and the maternal fish oil programmed reduced adipocyte size. Gene expression analysis results proposed the mechanisms that prompted differences in muscle fiber size area between diets namely, the increase in early myogenic marker expression, PAX7 and MYOD1 and an increase in a marker of myogenesis and angiogenesis, PDGFRβ. The increased expression of FABP4 seen in the perinatal fish oil diet groups may be attributed to a relatively new understanding of its function in muscle, and potentially an increase in fatty acid oxidation. Altering the hypertrophic growth rate of high efficiency broilers may assist in preventing growth that exceeds nutrient and oxygen provision seen in wooden breast. Primary satellite cells were collected from a subset of chicks that only differed by the maternal fish or soybean oil diets. Satellite cells isolated from the maternal fish oil group accumulated significantly less triglyceride versus maternal soybean oil. Decreasing elevated adipogenesis seen in the development of wooden breast may help to lessen the severity of the myopathy. In conclusion, future research is needed to identify the long term impacts fish oil supplementation can have on muscle development and adiposity in broilers at market age.