Fish need special care during winters and especially in cloudy days. As temperature of the surface water is colder than the bottom layers, the fish prefers to live in the bottom zone. Farmers shall keep the water depth up to 6 feet, so that it gets enough space for hibernating in the warmer bottom zone. Dr. Bhanu prakash. Ch expert from Krishi Vigyan Kendra,Tarn Taran said that as day length and light intensity also decreases during winters, oxygen levels decline in ponds due to reduced photosynthetic activity. The situation further heightens during continuous cloudy days. The farmers are advised to aerate their ponds either by adding fresh water or by using aerators, especially during early hours of the day. Feed intake of fish decreases with decrease in temperature as its digestive system becomes sluggish. Hence, it is essential to reduce the feed ratio by 30-75% depending on the temperature. In case the temperature falls below 50 C, it is advised to stop feeding. Excess feed remains unconsumed and accumulates at the pond bottom, which deteriorates the water quality. Farmers are further advised to use low protein diets. It is also necessary to reduce/stop adding organic manures such as cow dung, poultry droppings and pig dung in the pond as rate of decomposition of organic manures declines due to poor microbial activity during winters. During winters, various fungal, bacterial and parasitic diseases like fin rot, gill rot, EUS and argulosis may appear in the fish. Treat the pond with CIFAX @ 400 ml/acre just before the onset of winters. Also treat the pond with potassium permanganate @ 1-2 kg/acre or limestone @ 50-100 kg/acre also helps in protecting fish against disease outbreak during winters. Farmers may call Dr. Bhanu Prakash, Assistant professor (Fisheries), Krishi Vigyan Kendra, Tarn Taran on 6300487614.
