Effect of chick weight on performance and carcass yield of broilers

Abstract

Estudou-se a influência do peso de pintos da linhagem Ross sobre o desempenho de 1 a 43 dias de idade e sobre os rendimentos de carcaça e de cortes nobres. Pintos das categorias de peso leve, média e pesada foram aleatoriamente distribuídos em seis repetições de 30 machos e 30 fêmeas cada. As rações utilizadas foram as mesmas para todos os tratamentos. Avaliaram-se o peso vivo, o consumo de ração, a conversão alimentar, a viabilidade, os rendimentos de carcaça e de cortes (peito, coxa, asa e dorso) e a porcentagem de vísceras (moela, coração, fígado e intestinos). As aves da categoria pesada apresentaram maior peso (P<0,05) que as da categoria leve durante todo o período de criação. As da categoria pesada consumiram mais ração (P<0,05) que as das categorias leve e média. Não houve diferença entre os tratamentos quanto à conversão alimentar e à viabilidade. Não foram encontradas diferenças entre categorias de peso em relação ao rendimento de carcaça e as porcentagens de coração, moela e fígado (P>0,05). Quanto ao rendimento de carcaça, os machos foram superiores às fêmeas nas categorias média e pesada. O rendimento de coxa mais sobrecoxa na categoria pesada foi maior do que na categoria média (P<0,05). Os tratamentos influenciaram o peso corporal, o consumo de ração, os rendimentos de carcaça e coxa mais sobrecoxa e não influenciaram a conversão alimentar, a viabilidade, o rendimento de peito e a porcentagem de vísceras.Palavras-chave: frango de corte, peso do pinto, desempenho, rendimento de abate ABSTRACTThe influence of weight classes (light, medium and heavy) of Ross chicks on performance and carcass yield and main cuts, was studied using a completely randomized design with six replicates of 30 males and 30 females each. The chicks were fed on the same diets during the growing period (1-43 days). The live weight, feed intake, feed:weight gain ratio, viability, carcass yield and main cuts (breast, whole leg, wing and back) and percentages of giblets (gizzard, liver, heart and guts) were analyzed. The heavy weight class chicks were heavier (P<0.05) than the light weight class chicks, during all the growing period and showed higher feed consumption (P<0.05) than the light and medium classes chicks. No differences among weight classes chicks concerning feed:weight gain ratio, viability, carcass yield and percentage of heart, gizzard and liver were observed (P>0.05). The males showed higher carcass yield than the females of medium and heavy weight classes chicks. The whole leg yield of heavy weight class chicks was higher than the medium weight class chicks (P<0.05). Weight class influenced live weight, feed intake, carcass yield and whole leg but had no effect on feed:weight ratio, viability, breast yield and giblets percentage.

Novel 61-bp Indel of RIN2 Is Associated With Fat and Hatching Weight Traits in Chickens

“…For every 1 g increase in hatching weight, the slaughter weight increases by 9–13 g ( Singh and Nagra, 2006 ; Mendes et al, 2011 ). The economic value of high-hatching weight broilers is also generally higher than that of low-hatching weight broilers ( Lara et al, 2005 ). Analysis of the gene frequency in F 2 population and 8 chicken breeds revealed that the 61-bp insertion may be highly selected in WRR and WHL ( Table 1 ).…”

Growth Performance, Carcass Characteristics and Meat Quality of Griller-Type Broilers of Four Genetic Lines

“…In addition to the genetic potential of each line, the initial weight of the birds can also be regarded as responsible for the performance differences (Leandro et al 2006), as heavier day-old chicks have better overall performance. According to Lara et al (2005), each additional gram of initial body weight results in 13 additional grams more at slaughter age. Despite the differences in feed intake, weight gain, feed conversion and livability, no differences (p>0.05) were determined for the production efficiency index, the factor that is used to pay the producer.…”