ABSTRACT
This study aimed to assess the effects of breeder age on egg quality and amino acid and mineral transfer to the egg yolk and yolk sac of newly hatched chicks. Three ages (32, 42 and 52 weeks) of the same commercial flock of Hubbard breeders were studied. A total of 465 eggs were used for each age, with 60 being used for determining egg quality and amino acid and mineral content of yolk, and 405 for incubation period to obtain and evaluate the yolk sac of chicks. Breeders aged 52 weeks had heavier eggs and a higher percentage of yolk (p < 0.05), whereas 32-week-old breeders had higher eggshell percentage and thickness (p < 0.05). The percentage of protein deposited in egg yolk for 52-week-old breeders was higher than that for 32- and 42-week-old breeders (p < 0.05). Percentages of methionine, cysteine, met + cysteine, lysine, threonine, tryptophan, arginine and isoleucine in egg yolk for 32-week-old breeders were higher than that for 42- and 52-week-old breeders (p < 0.05). The transfer from breeder of phosphorus, potassium, calcium, magnesium, copper, iron, manganese and zinc to the yolk of eggs from 32-week-old breeders was greater than that for eggs from 42- and 52-week-old breeders (p < 0.05). Chicks from 32-week-old breeders had greater deposition of phosphorus and calcium in the yolk sac (p < 0.05). Breeder age did not affect the deposition of potassium, magnesium, copper, iron, manganese and zinc in the yolk sac of newly hatch chicks (p > 0.05). It can, however, be concluded that younger breeders deposit more amino acids and minerals in egg yolk, while embryos of older breeders seem to use the nutrients present in the yolk more efficiently during embryonic development.
Subject(s)
Egg Yolk , Yolk Sac , Amino Acids , Animals , Chickens , MineralsABSTRACT
ABSTRACT: This study evaluated the behavior and welfare conditions of laying chicks in the starter phase, fed with diets formulated with increasing levels of crude fiber (CF) and two feedstuffs with different fiber compositions. The experiment was developed at the Federal University of Goiás, in Goiânia - GO, Brazil. Three hundred Bovans White chicks were evaluated in a completely randomized design with a 2×2+1 factorial arrangement corresponding to two levels of CF in the diet (3.0 and 3.5%) and two fiber sources (wheat bran and sugarcane bagasse), plus a control treatment (maize- and soybean meal-based), totaling five treatments with six replicates of 10 birds each. Maintenance behavioral patterns and welfare were assessed at 21 and 42 days of age. There was no difference in behavior and classification by order of importance of the activities performed by the fiber-fed birds observed at 21 and 42 days, according to the Kruskal Wallis test (P>0.05). Medium and good welfare conditions were obtained with wheat bran at 3.5 and 3.0% CF, respectively, at 21 days of age. At 42 days, the use of sugarcane bagasse at the CF level of 3.5% and wheat bran at the level of 3.0%provided good behavior conditions. The use of crude fiber in the feeding of hens did not change their behavior.
RESUMO: Objetivou-se avaliar o comportamento de pintainhas de postura na fase de cria, alimentadas com dietas formuladas com aumento de fibra bruta e dois alimentos com composições de fibra diferentes. O trabalho foi realizado na Universidade Federal de Goiás, Goiânia, GO, utilizando-se 300 pintainhas Bovans White, em delineamento inteiramente casualizado e arranjo fatorial 2x2+1, com dois níveis de fibra bruta na dieta (3,0% e 3,5 % de FB), duas fontes de fibra (farelo de trigo e bagaço de cana) e o tratamento testemunha (ração a base de milho e farelo de soja), totalizando cinco tratamentos e seis repetições de 10 aves cada. Foram avaliados padrões de comportamento de manutenção e bem-estar aos 21 e 42 dias de idade. Não houve diferença no comportamento e na classificação por ordem de importância das atividades realizadas pelas aves alimentadas com fibra e observadas aos 21 e 42 dias pelo teste de Kruskal Wallis (P>0,05). Obteve-se condições média e boa com farelo de trigo e 3,5 e 3,0% de fibra bruta, respectivamente, com 21 dias de idade. Aos 42 dias, o uso de bagaço de cana ao nível de 3,5% de fibra bruta e o farelo de trigo ao nível de 3,0%, mostraram boas condições de comportamento. A utilização de fibra bruta na alimentação de frangas não alterou o comportamento das aves.
