Effects of Dietary Zinc Levels on the Growth Performance, Organ Zinc Content, and Zinc Retention in Broiler Chickens

Abstract

The objective of this study was to investigate the optimal zinc (Zn) requirement of broiler chickens based on Zn retention. On the day of hatch, 350 male Ross 308 broilers were randomly assigned to seven treatments with five replicates of ten birds each. Zinc was supplemented as ZnSO 4 •7H 2 O at 0, 20, 40, 60, 80, 100, or 120 mg/ kg in the starter diet (fed from 1 to 21 d of age) and at 0, 16, 32, 48, 64, 80, or 96 mg/kg in the grower diet (fed from 22 to 42 d of age). The analyzed Zn levels were 34.98 and 27.57 mg/kg in the basal starter and grower diets, respectively. Supplemental Zn levels did not influence body weight gain, feed intake, feed conversion ratio, or liver Zn content of broilers at 21 and 42 d of age (p>0.05). Tibia ash Zn content of 21-d-old broilers increased when Zn supplementation level increased from 0 to 40 mg/kg Zn in (p<0.05). The highest breast muscle Zn content in 42-d-old broilers was observed when 100 and 80 mg Zn/ kg was supplemented in the starter and grower diets, respectively. Fecal Zn content, Zn intake, Zn excretion, and Zn retention of 31-to 33-d-old broilers linearly increased with supplemental Zn levels (p<0.05). Zinc retention values, calculated as the difference between Zn intake and Zn excretion, were negative, about zero, and positive when starter/grower diets were supplemented with 0/0 and 20/16, 40/32, and 60/48 and 120/96 mg/kg, respectively. These results indicate that supplementing 40 and 32 mg Zn/kg in starter and grower diets, respectively, promote the growth performance of broiler chickens, while reduce Zn excretion in the environment.

Effects of Phytase Supplementation to Diets with or without Zinc Addition on Growth Performance and Zinc Utilization of White Pekin Ducks

“…These results are consistent with those reported by Mohana and Nys [36]. In addition, the value for Zn retention found herein agrees with those reported by other authors [10,36]. Similar to the present findings, Jondreville et al [15] found that 100 FTU of phytase were equal to 1 ppm of Zn, and that the Zn excretion could be reduced by 10% if a corn–soybean diet were supplemented with 500 FTU phytase/kg diet.…”

“…A comparison between NRC [3] recommendation and modern commercial strains of broilers suggests that industries often use a big safety margin of Zn in feed formulation [5], also considering that amount of Zn up to 2000 mg/kg in poultry diets does not negatively affect the bird performance [8]. However, high amount of Zn in the diets is responsible of the high excretion of this trace element into the environment [9] as fecal Zn content linearly increases with Zn dietary levels [10]. Thus, the European Commission has recently established a maximum limit for the total Zn content, including the supplemental premix, of poultry diets at 100 ppm [11].…”

Intestinal digestibility of selected minerals, growth performance and meat quality in turkeys fed diets supplemented with different sources and levels of zinc

“…The few studies which investigated the effect of Zn on carcass quality in poultry revealed no changes in the dressing percentage of chickens fed diets with graded levels of Zn (Zakaria et al, 2017;Zhang et al, 2018) or Zn, Mn and Cu (Sirri et al, 2016). According to some authors (Tronina et al, 2007), organic Zn can increase the proportion of breast and leg muscles in the carcass, dressing percentage, and the fat content of breast and leg muscles in broilers.…”

Zinc in Dog Nutrition, Health and Disease: A Review

“…In goats, the zinc content of bone and muscle was 87 and 122 mg/kg DM, respectively [ 90 ], and in broilers, the content of zinc in tibia ash, fresh breast muscle, and fresh liver was c.a. 360, 8.7, and 31 mg/kg, respectively [ 91 ], when fed the requirement of zinc for each species. Thus, animal species, presence/proportion of offal/bone, and feeding regime of animals comprising the meat meals affect the zinc content of the raw ingredients from animal origin.…”