Method for improving immunity and disease resistance of cage-cultured fishes during overwintering period

Abstract

The invention discloses a method for improving immunity and disease resistance of cage-cultured fishes during the overwintering period. The method comprises the steps of A, performing experimental treatment including culturing a control group in cages without interference during the overwintering period, culturing an experimental group in cages which are dragged once a week during the overwintering period to expose carassius auratus gibelio in air, then putting the fishes and the cages into water, and performing air exposure and fishing stimulus once for the overwintering fish inside the cages without artificial feedstuff feeding; B, performing overwintering testing including recording water temperature and providing natural lighting; C, before the overwintering testing, performing nutrition enrichment on the tested fishes inside the cage system for one month without feeding artificial composite feedstuff for all the cultured fishes; D, performing challenge test; E, after completing the overwintering test, performing aeromonas hydrophila liquid intraperitoneal injection on the fishes and then continuing to culture the fishes inside the original cages. The method for improving immunity and disease resistance of the cage-cultured fishes during the overwintering period is easy to implement and convenient to operate, enhances the immunity and the disease resistance to bacteria of the cage-cultured fishes and significantly improves the survival rate of the overwintering fishes infected with bacteria.

Description

technical field [0001] The invention belongs to the technical field of aquaculture, and more specifically relates to a method capable of improving the immunity and disease resistance of cage cultured fish during overwintering. Background technique [0002] Fish is a temperature-changing animal, and its body temperature changes with changes in the external environment. At the same time, fish are more sensitive to temperature changes in the external water environment, and the sensitivity of fish to environmental temperature also varies in different temperature ranges. Generally, fish are "cold sensitive", that is, the sensitivity responds when the temperature decreases. Enhanced and weakened when the temperature rises (Yi Xianghua et al., Overwintering experiment of large yellow croaker. Aquatic Science and Technology Information, 1998, 25(6): 261-264). For warm-water fish, winter is a harsh stage. Low water temperature increases temperature sensitivity. On the one hand, it m...

AI Technical Summary

Problems solved by technology

[0012] It can be seen that the metabolism, physiology, biochemical indicators, immunity and resistance to diseases of most warm-water fishes during the winter are double-affected by low water temperature and starvation, and are susceptible to infection and infection by bacteria, fungi and parasites. Invasion, leading to a significant increase in the mortality of wintering fish

However, most parts of our country are in temperate and sub-temperate environments, and warm-water cultured fish generally have bottlenecks in overwintering.