Growth curves for body weight and major component parts, feed consumption, and mortality of male broiler chickens raised to maturity

Abstract

Body weight; yield of the major carcass component parts of breast, leg, thigh, drumstick, breast meat, thigh meat, and drumstick meat; feed consumption; feed conversion; and mortality of male broiler chickens from two commercial strains were measured from hatching to 154 d of age. As no differences were observed between the two strains, for any of the traits measured, the statistical analysis was made using pooled data. Growth curves for BW, breast weight, and leg weight were calculated. The Richards function was chosen to fit the data. The type of the curves predicted was typically sigmoid. Asymptotic weights for BW, breast weight, and leg weight were estimated at 6,870.2, 1,744.2, and 851.5 g, respectively. Age at point of inflection, at which maximum growth rate is attained, was predicted at 44.4, 47, and 49.1 d, respectively. The percentage of breast and breast meat increased with age, whereas percentages of leg, thigh, and drumstick remained roughly constant. Weekly feed conversion was determined, and polynomial functions were applied to relate feed consumption and feed conversion to the age of the birds. Cumulative mortality increased with age, especially beyond 70 d of age, rising to 50% by the end of the experiment. Mortality was related to high incidence of leg weakness observed in the same period. The results of the current study provide information on the growth potential of contemporary, genetically improved broiler chickens by means of a mathematical model.

Performance and Economic Suitability of Three Fast Growing Broiler Strains Raised Under Farming Condition in Bangladesh

“…reported that strain and sex can affect feed intake and feed conversion ratio. Goliomytis et al (2003) reported that feed intake was comparable between Cobb-500 and shaver Starbro strains through 154 days of age. They reported that feed intake of broilers increased until 84 days of age and then declined until 112 days of age.…”

Utilization of Jack Bean (Canavalia ensiformis) Meal as a Substitute for Soybean Meal in Diet for Broiler Reared for 35 Days

“…This probably because the broilers in all giving methods, up to 35 days old, were still in very fast growth phase. Where according to Goliomytis et al (2003) maximum growth rate is achieved between the ages of 44 and 49 days. All these variables had similar pattern with the tendency that, eventhough statistically not different, the treatment of JB50-0 had slightly higher values compare to the others.…”

Economic issues of broiler production length

“…Net gain, which takes into account both the feed and rearing costs, reached a maximum between 42 and 49 days of age, and then decreased (Baéza et al, 2011). The results of Goliomytis et al (2003) showed that live bodyweight was rapidly increasing until 44 days of age only, at which maximal growth rate was attained. Beyond this age, growth rate declined and approached zero at maturity.…”

“…However, the effects on profit, meat product quality, the environment, and animal welfare have been little investigated (Baéza et al, 2011). Goliomytis et al (2003) made a study to investigate the growth pattern of chickens beyond the common slaughter age of 42 days to maturity. Schmidt (2008) carried out a study in an integrated company to evaluate live and economic performance of broilers as a function of market age.…”