Fish is a cold blooded animal and its body temperature varies with atmospheric temperature. During winter its metabolic rate decreases with decrease in temperature which leads to decreased feeding rate, growth rate and immunity towards diseases. The information was revealed by Dr. Asha Dhawan HOD college of Fisheries, Guru Angad Dev Veterinary & Animal Sciences University. She said that for the good health and adequate production, proper care is very necessary in this type of extreme winter season. Argulus and fungus often attack the fish and fish shows symptoms like white spots and mucus on body and fall of scales and fins etc. To prevent the fishes from diseases, adopt prophylactic measures like use of lime @ 50-100kg/acre (in two instalments after 15 days interval) and potassium permanganate @ 400-500 g/acre during winter months. During winter, shorter day length and cloudy days decrease the photosynthetic activities, which in turn decrease the oxygen production in water. Due to less dissolved oxygen in pond water, fish comes under stress and become more prone to diseases. So it is important to aerate the pond at early hrs and during mid day especially during cloudy days. She advised that avoid use of organic manures as oxygen is used for their decomposition process. Fish farmers should decrease the supplementary feed up to half. Describing the management of water she emphasized that keep the water depth more than 5 feet (as bottom layer is warmer than the surface layer and fish prefers to stay at pond bottom during winter).Add freshwater to increase the water temperature.If the farmer follow these management practices, he can avoid fish losses during winter.
In case of any symptom of disease, stop manuring and feeding, add freshwater and contact experts at College of Fisheries, GADVASU because university is always on beck & call of farmers.
