The genetic parameters of feed efficiency and its component traits in the turkey (Meleagris gallopavo)

Feed represents two thirds of the total costs of poultry production and feed requirements are an important consideration in the turkey industry. Furthermore, as genetic progress is made in body weight traits, feed consumption could be expected to increase since larger birds require more feed. Consequently, improving feed efficiency by identifying animals that require the same amount of feed as their contemporaries but have higher body weight or weight gain is valuable in the animal production industry. This is feasible in a breeding program, and genetic selection combined with management, has improved feed conversion ratio (FCR) in the turkey by approximately 20% between 1966 and 2003 [1].Feed efficiency is often assessed as either FCR or residual feed intake (RFI) [2]. The ratio of feed intake to weight gain, or FCR, provides an indication of a bird's ability to convert feed to body weight, however selection based on a ratio is not ideal [3]. The RFI trait attempts to isolate a measure of biological efficiency independent of production, which can include weight gain or carcass yield, and is estimated as the difference between actual feed intake and a predicted feed intake based on body weight and production [2]. The RFI and FCR traits have moderate heritability values in broilers [4,5]; however published parameters for feed efficiency traits including RFI in the turkey have not been reported.Reliable genetic parameters are essential for selection index design and to determine the correlated response to selection that will occur in other traits in a selection index. As a result, accurate estimates of genetic parameters enable turkey breeders to determine the impact that selection for feed efficiency will have on a breeding program. The objective of the present study was to determine the heritability of RFI and FCR, as well as their component traits in the turkey and to determine genetic correlations between the traits.Data collected on toms from a primary breeder tu