Chayane da Rocha

Vitamin E and selenium in broiler breeder diets: Effect on live performance, hatching process, and chick quality

This study evaluated the effect of different dietary vitamin E levels and different selenium sources on the productive and reproductive performance of broiler breeders. In total 640 females and 64 males between 22 and 52 weeks old were studied. A completely randomized experimental design in factorial arrangement, with 4 treatments of 8 replicates with 20 females and 2 males each, was applied. Treatments consisted of 2 vitamin E levels (30 and 120 mg/kg) and two selenium sources (sodium selenite and zinc-L-selenomethionine). Egg production (rate of lay and eggs per breeder), egg characteristics (egg, yolk, eggshell, and albumen weights), fertility, incubation responses (egg weight loss during incubation, hatchability, and hatching window), and hatchling characteristics (weight and yield) were evaluated. There was no influence of dietary vitamin E levels or selenium sources on egg production (P > 0.05). Mature breeders (47 weeks old) fed zinc-L-selenomethionine and 120 mg vitamin E/kg feed produced heavier eggs and albumen. Hatchability of the eggs of breeders fed 120 mg vitamin E/kg feed was higher than breeders fed 30 mg vitamin at 29 wks. The dietary inclusion of organic selenium also promoted heavier hatchling weight until egg production peak (33 wk), but did not influence hatchling quality or hatching window. It was concluded that the dietary supplementation of zinc-L-selenomethione and vitamin E (120 mg/kg feed) could be used to improve egg characteristics and incubation response.

Evaluation of the use of probiotics in diets with or without growth promoters for broiler chicks

Este trabalho foi realizado para avaliar o uso do probiotico Bacillus subtilis C-3102 (1010 ufc/g) em dietas contendo ou nao promotores de crescimento sobre o desempenho de frangos de corte no periodo de 1 a 42 dias de idade. Foram utilizados 1.200 frangos de corte da linhagem Cobb, distribuidos em delineamento inteiramente ao acaso com cinco dietas: controle negativo (sem promotores); Bacillus subtilis (30 g/t de racao); Bacillus subtilis (50 g/t de racao); Bacillus subtilis (30 g/t de racao) + de colistina (10 ppm); avilamicina (10 ppm) + colistina (10 ppm). Cada dieta foi avaliada em 10 repeticoes de 24 aves. Foram avaliados aos 21 e 42 dias o consumo de racao, o ganho de peso e a conversao alimentar e, aos 42 dias, o indice de eficiencia produtiva. Ao final do periodo experimental, observou-se aumento no consumo para a dieta com a menor dose de Bacillus subtilis (30 g) em relacao aquela com Bacillus subtilis (30 g) + colistina (10 ppm). Os valores de ganho de peso obtidos com a dieta com menor dose de Bacillus subtilis (30 g) e com avilamicina (10 ppm) + colistina (10 ppm) foram superiores aos das aves alimentadas com a dieta controle (sem promotores). Para conversao alimentar, os melhores resultados foram obtidos com o fornecimento das dietas com 50 g de Bacillus subtilis; com 30 g de Bacillus subtilis + 10 ppm de colistina; e com 10 ppm de avilamicina + 10 ppm de colistina. Na analise do indice de eficiencia produtiva, os melhores resultados foram obtidos com as dietas contendo aditivos (probioticos e/ou antibioticos) em comparacao a dieta controle. O probiotico Bacillus subtilis C-3102, na concentracao 1010 ufc/g, e um substituto eficiente de antibioticos.

Adição de complexo enzimático e da granulometria da soja integral desativada melhora desempenho de frangos de corte

This experiment was carried out to evaluate the effect of the enzymatic complex addition and deactivated full-fat soybean particle size on performance of broilers in the period from 1 to 42 days of age. Four hundred and eighty male broiler chicks from the Ross strain were used, allotted to a completely randomized factorial scheme 2x2 (enzyme x particle size). The experimental diets were based on corn, soybean meal and (±1.5 mm or ±4.0mm) deactivated full-fat soybean, with or without enzyme. The enzymatic complex (xylanase, b-glucanase, mannase, pectinase and protease) was supplied in the dose of 50g t-1ration. The enzymatic complex addition increased (P=0.0531) the diet intake in 4% and the weight gain in 2.8% in the final period. The feed intake increased 3% in the final period and 2% in the total period in poultry that were fed with fine particle size diet. In the initial period, the chicks that ingested the coarse particle size diet had a 5% weight gain increase and had the greater feed rates. The addition of the enzymatic complex in diets with deactivated full-fat soybean improves the performance of chickens. The use of the soy with fine particle size (1,5mm) in the initial phases for chickens is not recommended.

Effects of different limestone particle sizes in the diet of broiler breeders post molting on their performance, egg quality, incubation results, and pre-starter performance of their progeny

An experiment was conducted to test the hypothesis that a coarse limestone diet improves productivity, reproductive performance and the calcium utilization of molted broiler breeders. In total, 640 broiler breeder females, 73-week-old and sixty-four 27-week-old cockerels, Cobb 500, were evaluated during 10 weeks, according to a randomized block design composed of 4 treatments with 8 replicates each. Treatments consisted of diets with the inclusion of 100% fine limestone-fine PS (0.2 mm GMD-geometric mean diameter); PS1: 30% fine limestone+70% limestone with 1.0 mm GMD; PS2: 30% fine limestone+70% limestone with 2.0 mm GMD; and PS3: 30% fine limestone+70% limestone with 3.0 mm GMD. Calcium retention in the gizzard of the breeders, bone characteristics, and breeder performance, egg characteristics, eggshell quality, incubation performance, chick quality and yield, chick pre-starter live performance, and chick bone characteristics were determined. There was no significant difference (P>0.05) in the rate of lay, percentage of non-settable eggs, egg weight, egg shape index, egg specific gravity, eggshell weight, thickness, and percentage hatchability and egg weight loss of broiler breeders fed with diets with different limestone particle sizes. The chick quality and yield, chick pre-starter live performance, and chick bone characteristics were not affected (P>0.05) by any of the limestone particle sizes. It was concluded that live and reproductive performance parameters of broiler breeders post molting is not affected by limestone particle size in the feed.