Effect of an addition of phytase to diets with variable zinc and low phosphorus content on performance, carcass characteristics and bone mineralization of broilers
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Dosyalar
Tarih
2004
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
ECOLE NATIONALE VETERINAIRE TOULOUSE
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
A 6-week experiment with 960 unsexed one day-old broiler chicks was conducted to evaluate the effect Of Microbial phytase (Natuphos 500) on the performance. carcass characteristics and toe ash as a measure of bone mineralization when varying levels of zinc (Zn) and low phosphorus content in diet were used. Twelve treatments consisting of three levels of Zn (40. 60 and 160 mg/kg diet) and four levels of phytase (0, 500, 1000 and 1500 U / k2 diet) in 3 x 4 factorial arrangement were used with four replicates of twenty birds each. Increase of the dietary zinc content resulted in a non-significant reduction in the body weight gain (BWG), feed consumption (FC). weights of the carcass, neck, thighs, back + breast and a significant decrease (P< 0.05) in weight of wings. There was also a tendency of increasing feed/gain ratio and toe ash percentage. On the other hand. supplemental phytase induced significant increases of FC during the first (0 to 3 weeks), the second (4 to 6 weeks) periods and during all the experimental duration. and significant decreases of feed/gain ratios (for the second period and for all the experimental period). Carcass weights and their components were also increased by phytase supplementation (p < 0.05-0.01). The differences among Supplemental phytase with respect to these parameters have not been significant. In the experiment, significant Zn level x phytase level interactions (P< 0.05) have been observed for BWG. BWG have been significantly improved by phytase addition at three dietary Zn levels whatever the age period considered and the effects of this interaction on the BWG were different during the different age periods. Also. the negative impacts of increasing Zn levels on FC feed/ gain ratio and carcass traits (P> 0.05) have been completely corrected by inclusion of phytase to diets. The results indicate that supplementing microbial phytase to broiler diets with various levels of Zn has improved growth performances and carcass traits.
Açıklama
Anahtar Kelimeler
zinc, phytase, broiler, mineralization, growth, carcass traits
Kaynak
REVUE DE MEDECINE VETERINAIRE
WoS Q Değeri
Q4
Scopus Q Değeri
Q3
Cilt
155
Sayı
7
