TY - JOUR
T1 - Effect of the level and source of supplementary dietary zinc on egg production, quality, and zinc content and on serum antioxidant parameters and zinc concentration in laying hens
AU - Yu, Qifang
AU - Liu, Hu
AU - Yang, Kaili
AU - Tang, Xiaopeng
AU - Chen, Sijia
AU - Ajuwon, Kolapo M.
AU - Degen, Allan
AU - Fang, Rejun
N1 - Publisher Copyright:
© 2020
PY - 2020/11/1
Y1 - 2020/11/1
N2 - Zinc is vital for proper functioning of an animal. Two sources of zinc are commonly supplemented in animal feed, organic and inorganic zinc, and there are reports that the former is absorbed to a greater extent than the latter. We hypothesized that supplementary zinc would increase zinc content in eggs of laying hens and that organic zinc would be more effective than inorganic zinc. To test these hypotheses, we examined the effect of levels and sources of supplemental dietary zinc on average daily feed intake (ADFI), egg production, and zinc content in eggs and on serum antioxidant capacity and zinc concentration in laying hens. A total of 720 Roman laying hens (21-week-old) were randomly assigned to 5 treatment groups with 6 replicates, with 24 hens in each replicate. Two sources of zinc, organic (zinc amino acid complex) and inorganic (zinc sulfate), each with 2 levels, low (35 mg/kg) and high (70 mg/kg), comprised 4 treatment groups, and a control group without supplementary zinc was the fifth group. Seven days were allowed for adjustment to the conditions, and then measurements were taken over 42 D. There was no difference in ADFI, average egg weight (EW), ADFI-to-EW ratio, and egg quality (P > 0.05) among the 5 treatment groups; supplemental zinc increased serum concentrations of Zn2+ and Cu-Zn superoxide dismutase and tended to increase superoxide dismutase content (P = 0.065). Zinc content in eggs increased linearly with supplementary organic zinc (N = 18, R2 = 0.363, P = 0.008) and with supplementary inorganic zinc (N = 18, R2 = 0.366, P = 0.008) treatment, but there was no difference between the source treatments of zinc. Therefore, our first hypothesis was supported, but our second one was not supported. We concluded that zinc supplementation is effective in enhancing zinc content in eggs and in improving antioxidant capacity in laying hens.
AB - Zinc is vital for proper functioning of an animal. Two sources of zinc are commonly supplemented in animal feed, organic and inorganic zinc, and there are reports that the former is absorbed to a greater extent than the latter. We hypothesized that supplementary zinc would increase zinc content in eggs of laying hens and that organic zinc would be more effective than inorganic zinc. To test these hypotheses, we examined the effect of levels and sources of supplemental dietary zinc on average daily feed intake (ADFI), egg production, and zinc content in eggs and on serum antioxidant capacity and zinc concentration in laying hens. A total of 720 Roman laying hens (21-week-old) were randomly assigned to 5 treatment groups with 6 replicates, with 24 hens in each replicate. Two sources of zinc, organic (zinc amino acid complex) and inorganic (zinc sulfate), each with 2 levels, low (35 mg/kg) and high (70 mg/kg), comprised 4 treatment groups, and a control group without supplementary zinc was the fifth group. Seven days were allowed for adjustment to the conditions, and then measurements were taken over 42 D. There was no difference in ADFI, average egg weight (EW), ADFI-to-EW ratio, and egg quality (P > 0.05) among the 5 treatment groups; supplemental zinc increased serum concentrations of Zn2+ and Cu-Zn superoxide dismutase and tended to increase superoxide dismutase content (P = 0.065). Zinc content in eggs increased linearly with supplementary organic zinc (N = 18, R2 = 0.363, P = 0.008) and with supplementary inorganic zinc (N = 18, R2 = 0.366, P = 0.008) treatment, but there was no difference between the source treatments of zinc. Therefore, our first hypothesis was supported, but our second one was not supported. We concluded that zinc supplementation is effective in enhancing zinc content in eggs and in improving antioxidant capacity in laying hens.
KW - egg quality
KW - laying hen
KW - performance
KW - zinc-rich egg
UR - http://www.scopus.com/inward/record.url?scp=85090300644&partnerID=8YFLogxK
U2 - 10.1016/j.psj.2020.06.029
DO - 10.1016/j.psj.2020.06.029
M3 - Article
C2 - 33142541
AN - SCOPUS:85090300644
SN - 0032-5791
VL - 99
SP - 6233
EP - 6238
JO - Poultry Science
JF - Poultry Science
IS - 11
ER -