The effect of dietary phytase on broiler performance and digestive, bone, and blood biochemistry characteristics

The dietary inclusion of phytase increases nutrient and energy bioavailability for broilers. The effect of phytase increases nutrients and energy bioavailability for either the objective of this experiment was to evaluate the influence of nutrient and energy reduction in diets supplemented with phytase on the performance, gastrointestinal pH, organ and bone composition, and blood biochemistry of broilers between eight and 21 days of age. In the study, 1.120 male Cobb 500(r) broilers, with 161±1g average weight, were used. At eight days of age, birds were distributed according to a completely randomized experimental design with seven treatments in a 3x2+1 factorial arrangement with eight replicates of 20 broiler each. Treatments corresponded to reduction of calcium (Ca) and phosphorus (P), amino acids and energy, or reduction of Ca, P, amino acids and energy; supplementation or not of phytase; and a positive control treatment. Broiler fed the diet with reduced Ca and P levels and phytase supplementation presented the best performance of all groups. The diet with reduced amino acid and energy levels and phytase addition reduced gizzard and proventriculus pH. Dietary Ca and P reduction increased relative liver and heart weights, as well as albumin blood levels. The bones of broilers fed phytase-supplemented diets presented higher ash content

Performance of layers fed diets containing different oils

A trial was carried out at the Animal Science Department of the Federal University of Viçosa to evaluate the performance of heavy and light layers. During four periods of twenty-eight days, 432 layers in the second production cycle, being 216 Hy Line W36 (light birds) and 216 Hy Line Brown (heavy birds), were used. A completely randomized experimental design with a 1+(4x2x2) factorial arrangement (one control treatment, four oil sources, two inclusion levels, and two genetic lines) with four replicates of six birds per experimental unit, was applied. The treatments consisted of diets containing 16.5% crude protein, formulated to supply the nutritional requirements, and the inclusion of each oil source at 2 or 4%. Soybean, canola, linseed and fish oils were used. The control diet did not contain any oil. The studied parameters were: feed intake (g/hen/day), egg production (%), egg weight (g), egg mass (g/hen/day), feed conversion ratio (kg feed /dozen of eggs and per kg eggs). Oil levels and sources did not influence egg mass, feed conversion ratio (per kg eggs and dozen eggs), or egg production. During the first three periods, independently of oil source or genetics, eggs from layers fed 4% oil were the heaviest, except for those of light birds fed soybean oil during the third period, which egg weight was similar for the 2 and 4% levels. Light layers presented lower feed intake and better feed conversion ratio (per kg eggs and dozen eggs) as compared to heavy layers, and there was no influence of the evaluated oil sources on feed intake

Resultados de Pesquisa em Nutrição de Aves no Brasil: Resumo dos Ultimos 5 anos Results of Poultry Nutrition Research in Brazil: A Summary of the Last 5 years

Foi realizada uma revisão bibliográfica sobre as pesquisas brasileiras na área de nutrição avícola, entre 1994 a l999. Nesse período, foi publicado um total de 496 trabalhos, com uma média de 82,7 trabalhos/ ano. Os trabalhos na área de nutrição revelaram que 64,52% foram realizados com frangos de corte; 24,19%, com poedoiras e aves de reposição; 3,93%, com matrizes pesadas; e 7,66%, com outras aves. Com relação às publicações em forma de resumos expandidos, foram publicados 226 e 163 resumos, nos Anais das Reuniões Anuais da Fundação APINCO de Ciência e Tecnologia Avícolas e da Sociedade Brasileira de Zootecnia, respectivamente. Na Revista da Sociedade Brasileira de Zootecnia e no Arquivo Brasileiro de Medicina Veterinária e Zootecnia foram publicados, respectivamente, 65 e 34 trabalhos completos. Os pesquisadores das instituições UFV, UNESP-Jaboticabal e UFRGS publicaram no total 104, 92 e 46 trabalhos. As pesquisas concentraram-se principalmente nas áreas de proteína/aminoácidos (21,77%), avaliação de alimentos (21,77%), minerais (19,15%) e aditivos (16,33%).<br>A literature review of the papers published in the area of poultry nutrition was done considering Brazilian publications from the period of 1994 to 1999. During this period a total of 496 papers were published, with an average of 82. 7 papers/year. The publications in nutrition revealed that 64. 52% were made with broiler chickens, 24. 19% with laying hens and replacement birds, 3.93% with broiler breeders and 7.66% with other type of birds. Considering the publications in the form of summary, 226 and 163, were published in the Proceedings of Fundação APINCO de Ciência e Tecnologia Avícola and Sociedade Brasileira de Zootecnia, respectively. In the Revista da Sociedade Brasileira de Zootecnia and Arquivo Brasileiro de Medicina Veterinária e Zootecnia were published, 65 and 34 papers, respectively. Researches in the Universities UFV, UNESP-Jaboticabal and UFRGS, accounted for a total 104, 92 and 46 papers, respectively. The papers in poultry nutrition concentrated mainly in the area of protein/amino acid (21.77%), feedstuffs evaluation (21.77%), minerals (19.15%) and additives (16.33%)