Growth and deposition of body components of intermediate and high performance broilers

Abstract

The objectives of the present study were to determine the parameters of Gompertz equations and to determine curves and growth rate, feed intake and body component deposition, as well as allometric coefficients of body water, protein, and fat relative to live weight of male and female broilers of intermediate performance (C44) and high performance (Cobb-500) genetic strains. In total, 384 one-d-old chicks were distributed into four treatments: male Cobb 500, male C44, female Cobb 500, and female C44, with six replicates of 16 birds, according to a completely randomized experimental design. Average body weight, weight gain, and feed intake were weekly determined, and six birds, representing the average weight of each treatment, were sacrificed to determine body composition. Growth curves were built applying Gompertz function, with excellent fit, and growth, feed intake, and tissue deposition rates were obtained by its derivatives. Superior growth rate was obtained for Cobb 500 male broilers. This genetic strain has higher feed intake capacity, which is achieved earlier than in the C44 strain. Protein and fat deposition maturity was reached earlier in males than in females in Cobb 500. The allometric coefficients showed earlier maturity for body water in C44 and females. In terms of body protein, male Cobb 500 broilers reached maturity earlier than females and C44. Body fat deposition maturity was reached earlier in Cobb 500 than in C44. The Gompertz equations obtained in the present study efficiently described body growth, feed intake, and deposition of body components, with a coefficient of determination higher than 0.99.

Practical Assessment of Spaghetti Breast in Diverse Genetic Strain Broilers Reared under Different Environments

“…Improvements in the environmental conditions associated with genetic selection have allowed accelerated growth rates in broiler chickens. The Cobb genetic strain is the most frequently used in commercial broiler production due to its adequate final weight gain (Henn et al, 2014), excellent live performance, and high carcass yield, particularly breast yield. The Ross genetic strain is characterized byslow initial growth rate, which is compensated from 21 d of age, and may reach the same slaughter weight and carcass yield as Cobb broilers when slaughtered at 45 days of age (Kokoszyński et al, 2017).…”

Accumulation of α-hexabromocyclododecane (α-HBCDD) in tissues of fast- and slow-growing broilers (Gallus domesticus)

“…According to equations predicting the body lipid content of broilers of different strains from their BW (Henn et al, 2014), FG and SG broilers at slaughter would contain 118 and 131 g lipid kg -1 BW at slaughter. Assuming that most of the body lipids not included in the assessed tissues are made of neutral lipids (osseous, intermuscular, subcutaneous and visceral fat) and, thus, are as concentrated in -HBCDD as abdominal fat, the body burden of -HBCDD would be 31% higher in SG than in FG broilers (126 vs. 96 µg), for -HBCDD intake 51% higher (253 vs. 167 µg), yielding an assimilation efficiency 8 percentage units lower (50 vs. 58%) ( Table S8).…”

Evaluación del comportamiento productivo de pollos Cobb 500 sometidos a restricción alimenticia como estrategia sostenible de control nutricional

“…Resultados similares fueron obtenidos por Sugeta et al (13); Morais et al (16) y Urdaneta-Rincón y Leeson, (43), razón por la cual la estrategia de supresión alimenticia aplicada en el presente estudio no ejerció ningún efecto negativo sobre la ganancia de peso, lo que sugiere una compensación favorable del crecimiento. En cuanto al CA, este fue ligeramente superior en los animales alimentados ad libitum, registrándose un valor promedio total de 4181.01 ± 306.46 g entre tratamientos, muy similar al calculado por Henn et al (37); Mendes et al (44), e InfanteRodríguez et al (45). Sahraei (12) afirma que la tasa de crecimiento está relacionada con el CA, por lo que la restricción alimenticia podría inhibir considerablemente la GTP; sin embargo, el análisis estadístico arrojó que el CA registrado en el T 3 y T 4 , fue significativamente menor (p < 0.05) con respecto al grupo control, en tal sentido, los criterios prácticos de análisis productivo empleados actualmente por los avicultores, sugieren que el valor calculado de CA en el T 4, probablemente ejerce un impacto económico significativo, considerando que la alimentación constituye el costo variable más alto (46).…”