Dietary supplement of Antheraea pernyi cecropin enhances the growth rate and disease resistance of the Yesso scallop, Patinopecten yessoensis

Abstract

A feeding trial was carried out for 30 days to investigate the impacts of dietary immunity induced A. pernyi pupae powder (IPP) and A. pernyi cecropin (AC) on the growth, immune-related enzyme activities and disease resistance in Yesso scallop, Patinopecten yessoensis. A total of 320 scallops, with an average weight of 54.75 ± 0.07 g were randomly divided into four treatment groups: control group (provided with a diet of spirulina powder and microalgae), groups with basic diet supplemented with A. pernyi pupae powder (NPP, 2 % of the final concentration), immunity induced A. pernyi pupae powder (IPP, 2 % of the final concentration), and A. pernyi cecropin (AC, 2 % of the final concentration), respectively. The results showed that the specific growth rate (SGR), lysozyme (LSZ), acid phosphatase (ACP) and superoxide dismutase (SOD) were significantly higher in the scallops fed with AC than in the other groups (P < 0.05). Unfortunately, NPP and IPP exhibited an inhibitory effect on SGR and all the detected immune index parameters of the scallops, whereas the activities of LSZ and SOD decreased significantly compared to those of the control group (P < 0.05). Disease resistance was significantly increased in the scallops treated with AC, recording the lowest mortality percentage of 43.3 % following a challenge with Vibrio chagasii (P = 0.0001). The results of the present study suggest that supplementing the diet with AC at 2 % can significantly enhance the weight gain rate, immunity and disease resistance of scallops.