Open AccessGrowth, body composition and intestinal enzyme activities of juvenile Jian carp ( Cyprinus carpio var. Jian) fed graded levels of dietary zinc
Author(s) -
TAN L.N.,
FENG L.,
LIU Y.,
JIANG J.,
JIANG W.D.,
HU K.,
LI S.H.,
ZHOU X.Q.
Publication year - 2011
Publication title -
aquaculture nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.941
H-Index - 79
eISSN - 1365-2095
pISSN - 1353-5773
DOI - 10.1111/j.1365-2095.2010.00793.x
Subject(s) - cyprinus , carp , biology , zinc , feed conversion ratio , amylase , zoology , medicine , hepatopancreas , protein efficiency ratio , endocrinology , weight gain , alkaline phosphatase , digestive enzyme , food science , enzyme , biochemistry , chemistry , body weight , fish <actinopterygii> , fishery , organic chemistry
A 6‐week trial was carried out with 900 juvenile Jian carp ( Cyprinus carpio var. Jian) to investigate the effects of dietary zinc on growth, body composition and intestinal enzyme activities. Diets supplemented with increasing levels (15.3, 26.9, 40.8, 58.2, 68.9 and 92.5 mg Zn kg −1 ) of zinc lactate were fed to Jian carp (mean initial weight 15.7 ± 0.01 g). Results indicated that per cent weight gain (PWG), feed efficiency (FE), protein efficiency ratio (PER) and lipid productive value (LPV) enhanced with dietary zinc levels up to 40.8 mg kg −1 diet ( P < 0.05), and plateaued thereafter ( P > 0.05). Feed intake (FI) was similar to that observed for PWG. Intestosomatic index (ISI), relative gut length (RGL), hepatopancreas protein content (HPC), intestine protein content (IPC), trypsin, chymotrypsin, lipase, amylase, alkaline phosphatase (AKP), Na + , K + ‐ATPase and γ‐glutamyl transpeptidase (γ‐GT) activities were all higher by dietary zinc supplementation than zinc un‐supplementation ( P < 0.05). These results suggested that zinc could promote growth and increase nutrient deposition and intestinal enzyme activities. The dietary zinc requirements (use zinc lactate as zinc source) of juvenile Jian carp (15.7–42.2 g) based on PWG and serum zinc were 48.7 and 43.2 mg Zn kg −1 diet, respectively.