Efeito da adição da enzima fitase sobre o desempenho e a digestibilidade ileal de nutrientes

Abstract

RESUMO -Conduziu-se um experimento utilizando 384 pintos de corte machos, Avian Farm, para se avaliar o efeito da fitase sobre o desempenho das aves e os coeficientes de digestibilidade ileal aparente da matéria seca (MS), da proteína bruta (PB), da energia bruta (EB), do fósforo (P) e do cálcio (Ca) e os valores de energia digestível ileal aparente (EDIap) e energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) de dietas à base de milho e farelo de soja com diferentes níveis de Ca e P disponível (P d ). Foram utilizados pintos no período de 10 a 24 dias de idade, em arranjo fatorial 2 x 3, com oito repetições contendo oito aves cada. As dietas foram formuladas contendo dois níveis de Ca e P d : normal (0,93%Ca/0,45%P d ) e baixo (0,80%Ca/0,33P d %) x três níveis de fitase (0 -controle, 500 FTU -fitase 1 e 750 fitase -2). Óxido crômico (0,5%) foi adicionado às dietas a fim de se estimar o fator de indigestibilidade. A fitase 1 melhorou o ganho de peso em 3,4% e a fitase 2, em 2,8%. Ambas as enzimas melhoraram a conversão alimentar em 3% e a digestibilidade da PB, da EB, do P e do Ca. A adição das enzimas, também, melhorou significativamente a energia digestível ileal aparente (EDI ap ), entretanto não se observou efeito da adição de fitase sobre EMA n .Palavras-chave: digestibilidade de nutrientes, enzima, fitase, frangos de corte, milho e farelo de soja Effect of Phytase Suplementation on the Performance and Ileal Digestibility of NutrientsABSTRACT -One experiment was conducted to evaluate the effect of microbial enzymes, phytase, on the performance of the birds and on the digestibility coefficient of dry mater (DM), crude protein (CP), phosphorus (P) and calcium (Ca) and the values of apparent ileal digestible of energy (AIDe) and nitrogen corrected apparent metabolizable energy (AMEn). A total of 384 Avian Farm male broiler chicks, 10 days old, during 14 d-trial were used in a factorial arrangement of 2 x 3, with eight replicates, eight chicks per unit were used. The diets were formulated to contain two levels of Ca and available P normal (0.93%Ca/0.45%P d ) and low (0.80%Ca/0.33%P d ) x three level of phytase (o -control, 500 FTU phytase -1 and 750 phytase 2). Chromic oxide (0,5%) was added to the diets, as an indigestible marker, to estimate ileal digestibility. Phytase 1 improve weight gain in 3.4% and phytase 2 in 2.8%. Both enzymes improved feed:gain ratio in 3% and the digestibility of CP, E, P and Ca. Phytase addition, also, improved AIDe, however the enzyme did not improve the EMA n .

Effect of dietary phytase suplementation on the performance, bone densitometry, and phosphorus and nitrogen excretion of broilers

“…The results obtained for the total rearing period showing that increasing phytase levels had negative effects on performance parameters are different from literature results (Tejedor et al, 2001;Lan et al, 2002;Wu et al, 2004). However, in literature, phytase nutritional matrix results were not considered in the formulation of the experimental diets, and therefore Using low available phosphorus levels and phytase inclusion, Persia & Saylor (2006) showed that phytase improved the performance of 8-to 22-day-old broilers, as opposed to Angel et al (2006), who did not find any broiler performance differences during the starter phase when adding phytase to low available phosphorus diets.…”

Digestibility, Determination of Metabolizable Energy and Bone Mineralization of Broilers Fed with Nutritionally Valued Phytase

“…The metabolizable energy and apparent metabolizable energy corrected for nitrogen from 15-20 days of age did not differ among the treatments (Table 5), so the enzyme phytase was not able to provide energy increase as enunciated by Tejedor et al (2001), who worked with different breed of broiler chickens (Avian Farm) from the one used in this study. Lan et al (2002), when analyzing the metabolizable energy content in the corn and soybean based feed supplemented with phytase enzyme (250-1000 uft kg -1 ) for Avian chickens in the initial and final phases, found higher values of apparent metabolizable energy when compared to a diet with normal levels of phosphorus and without enzyme supplementation.…”

“…Boling et al (2000) reported that supplementation of diets with phytase did not improve ileal digestibility of amino acids in chicks. In contrast, Tejedor et al (2001) evaluated 10-24 day old chickens, and found better digestibility values of calcium, phosphorus, protein and apparent energy with the addition of phytase (500-750 uft kg -1 (unit of phytase per kg)) and a better utilization of protein, for example, by breaking the nutrient complex (proteinphytic acid) by the use of phytase breaking and releasing phytate protein and amino acids.…”

“…Nutritionally, using exogenous enzymes such as phytase, for example, allows nutrients to be better used by the animal, so there would be an increase in the use of phosphorus, as well as amino acids and energy, reducing the feed formulation´s final cost (Tejedor et al, 2001).…”

Redução da exigência de fósforo disponível em dietas com adição de fitase para frangos de corte machos de oito aos 21 dias de idade

“…Para a variável ganho de peso, os dados foram iguais, o que pode ser explicado pela digestibilidade ileal da proteína bruta, do cálcio e do fósforo, que, quando usada fitase, aumenta a quantidade de nutrientes [23], o que justificaria também o peso final das aves.…”