title: Mathematical characterization of broiler carcass yield dynamics.
abstract: Modeling of broiler chicken supply-chain economics depends on robust biological models of growth and yield of broiler chickens. In this paper, 8 dynamic nonlinear broiler carcass and carcass part yield models were evaluated statistically for their suitability for predicting weights of carcass parts. The analysis employed 4 sigmoidal (S) models (Gompertz, modified Gompertz, Richards, and Lopez) describing carcass part weight as a function of age, as well as 3 diminishing returns (DR) models (Lopez, Mitscherlich, and log linear), and a log-linear proportional yield (PY) model, which describe carcass part yield and weight, respectively, as a proportion of feather- and fat-free empty body mass (FFEBM). Three S models with a flexible point of inflection were better able to predict carcass part weights than a fixed point of inflection Gompertz model and, in general, the DR models. The log-linear models were the only models that converged in 100% of the evaluations. The allometric PY model predicted weights for most carcass parts with the smallest degree of error and with substantially less bias than the DR log-linear model. Estimates of the coefficients for the log-linear PY model are included for 12 key carcass parts. Estimates of carcass chemical composition are presented for the log-linear PY model.
authors.affiliation: Livestock Development Division, Alberta Agriculture, Food and Rural Development, Edmonton, Alberta, Canada T6H 5T6. martin.zuidhof@gov.ab.ca
authors.forename: M J
authors.initials: MJ
authors.lastname: Zuidhof
mesh_terms: D000818:Animals; D002645:Chickens / Q000033:anatomy & histology*; D005260:Female; D008297:Male; D008433:Mathematics; D008460:Meat / Q000032:analysis; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000737:chemistry; D009929:Organ Size; D011202:Poultry Products / Q000032:analysis