Abstract
Simple SummaryThe environment sustainability of farms is extremely important for the future of the world. In this context, the lowering of the pollution from intensive poultry farms is necessary. Due to its low levels and low digestibility in feeds, Zn is often overdosed in poultry feed, and its excess in the excreta can accumulate in the soil, inhibiting the growth of soil microorganism as well as altering their morphology and metabolism, thus reducing the crop yield and quality. Enzymes, such as phytase, can breakdown the linkage of Zn with phytic acid in vegetable feeds, thus increase the Zn availability for animal digestion. In this way, very low supplementation of Zn to the diets can meet the requirement of poultry.The effect of phytase and inorganic Zn supplementation was studied in 180 male White Pekin ducks (WPD) from 1 to 56 days of age. The birds were divided into four groups fed the same basal diet (containing 26 ppm of Zn from raw materials): the control group did not receive Zn supplementation; the second group was supplemented with 30 ppm of Zn oxide; and the third and fourth groups were fed the control and the 30 ppm diets, respectively, both supplemented with 500 U of E. coli phytase. Each group contained five replicates of nine ducks. The body weight and feed intake were recorded at 1, 28 and 56 days of age. At 56 days of age, five birds/group were used to measure feed digestibility and five other birds/group were slaughtered. Zn at 30 ppm increased the body weight gain (BWG, p < 0.01) and feed intake (p < 0.05) and improved the feed conversion (FCR, p < 0.05) of the growing ducks. The Zn retention and Zn level in the excreta increased (p < 0.01) due to Zn supplementation. The addition of phytase improved BWG (p < 0.01) and FCR (p < 0.05) of growing ducks. The use of phytase reduced (p < 0.01) the level of Zn in duck excreta. Phytase supplementation to the basal diet at 30 ppm seems to be adequate to meet Zn requirements for ducks without further Zn additions.
Highlights
Zinc (Zn) is an essential trace mineral with several roles in animal metabolism, acting as a functional component of more than 200 enzymes [1,2]
The groups were subjected to four dietary treatments as follow: the first group was fed basal diets unsupplemented with Zn oxide or phytase; the second group was fed the basal diets supplemented with 30 ppm of Zn oxide (72% Zn); the third group was fed the basal diets supplemented with 500 U of E. coli phytase (E. coli 6-phytase, 500 U/kg diet; Danisco Animal Nutrition, England); and the fourth group was fed the basal diets supplemented with 30 ppm of Zn oxide and 500 U of E. coli phytase
The grower and the finisher basal diets used in the trial contained 26 ppm of Zn from raw materials (Table 1) as determined by atomic absorption spectrometry
Summary
Zinc (Zn) is an essential trace mineral with several roles in animal metabolism, acting as a functional component of more than 200 enzymes [1,2]. In the NRC guidelines [3], Zn requirements for ducks are not provided; the dietary requirement of Zn for ducks is based on those for other bird species. Zn is required for eggshell deposition [4]; inadequate amount of Zn negatively affects the feed intake, growth rate and feed conversion ratio of broilers [5]. Abnormalities in the immune responses, as well as reproduction, skeletal and skin disorders can be tied to the deficiency of Zn in poultry diets [6].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
