Níveis de fósforo disponível em rações suplementadas com fitase para frangos de corte dos 22 aos 42 dias mantidos em ambiente de alta temperatura

• Autor(a) principal: Tizziani, Tarciso
• Data de Publicação: 2014
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: LOCUS Repositório Institucional da UFV
• Texto Completo: http://locus.ufv.br/handle/123456789/5812
• topic: Frango de corte - Alimentação e rações; Ambiente térmico; Fósforo disponível; Fitase; Broiler - Food and rations; Thermal environment; Available phosphorus; Phytase; CNPQ::CIENCIAS AGRARIAS::ZOOTECNIA

Two experiments were conducted to evaluate the effect of available phosphorus (aP) levels in diets suplemented with or whithout phytase on perfermance, carcass charactheristics and bone parameters in broilers from 22 to 42 days, maintained in high temperature, using two methodologies. In each experiment, 336 male chicks were distributed in a completely randomized desing with six treatments, being a positive control (0,354 e 0,309% of aP without phytase from 22 to 33 and 34 to 42 days, respectively), and more five rations with phytase comercial Quantum Blue® (500 FTU) and aP reduction (0,354; 0,294; 0,233; 0,173; 0,112% e 0,309; 0,258; 0,207; 0,156; 0,106 from 22 to 33 and 34 to 42 days, respectively. The diets were isonutritives, except for aP (Ca:aP ranging) in the experiment 1 and aP and Ca (Ca:aP fixed in 2.1:1). In both experiments were evaluated the performance, carcass charactheristics and boné parameters. The birds received the experimental diets and water ad libitum throuhout the experiment. At the end of the experimental period, two birds per replicate, with closest average weight were slaughtered, eviscerated and weighed to determine the absolute and relative weight of carcass and prime cuts. Other two birds per replicate were slaughtered to tibiae removed and the determination of the deposition of ash, calcium and phosphorus in the bone. In experiment 1, there was no effect of diets on feed intake (FI), weight gain (WG) and feed conversion (FC) and carcass characteristics. An increase in the deposition of calcium and Ca:P ratio deposited in bone of animals in groups 0,233; 0,173; 0,112% and 0,207; 0,156; 0,106%, from 22 to 33 and 34 to 42, respectively, compared to group control by Dunnet test. In experiment 2, there was no effect of diets on FI, WG, FC, absolute and relative weight of the carcass and prime cuts. For bone characteristics when compared to the control treatment, corresponding to the animal group fed the lowest level of aP showed lower ash and calcium deposition in bone, and the animals of groups that were fed with 0,173; 0,112% and 0,156; 0,106%, from 22 to 33 and 34 to 42 days had lower Ca:P ratio in bone. In experiment 1, we conclude that diets supplemented with phytase and low levels of aP does not affects with the performance and carcass characteristics of broilers from 22 to 42 days old in high temperature environment, however increases the deposition of Ca and the relationship Ca:P in bone. In experiment 2, diets supplemented with phytase and low levels of Pd and Ca does not interferes with the performance and carcass characteristics, however, decreases bone mineralization, calcium deposition and Ca:P ratio of bones in broilers from 22 to 42 days at room created high temperature.