Fish Farming Livestock: Rohu

General Information

It is a major Indian carp which is found in Southern Asia and is very important. It belongs to the “Cyprinidae” family and genus “Labeo”. This fish is also known as “Rui”, “Ruee” or Tapra. It has a small head, a sharp face and a lower lip that is frill-like, a long and circular body, a brown recolour body coat and an almost red colour cane. Its whole body is covered with scales except fins and head. There are a total of 7 fins present on the body of Rohu. It has a maximum length of 1m. It mainly eats rotten weeds and leaves waste material. During the monsoon season, the Rohu fish gives eggs once in a year. This fish is most famous and popular because of its taste and high market demand. It is used as a culture species in aquaculture. It is mostly found in freshwater ponds, ditches, canals, rivers, lakes etc. It is reared along with mrigala and Catla fishes in equal proportions. This breed has an average of 0.08 million per acre per year combined production. It gives around 2.0-2.5 lakh eggs per kg of their weight. The weight of the fish depends upon several factors such as stock in the pond, water condition, depth, size of the fish at the time of stocking, type of feed etc. If the size of the fingerling at the time of stocking is 2½-3inch i.e. in February-March month, then it attains the weight of approximately 1kg up to December month. If 10,000 fingerlings are stocked then the recovery of rohu fish is about 6,000. 

Feed

Artificial diet: Normally artificial fish feed is available in the markets. This feed is available in the form of pellets i.e. wet pellets and dry pellets. In a wet pellet, to make the feed hard Carboxy methyl cellulose or gelatin is added and then it is thinly crushed and prepared into pellets. It is healthy but it can’t be stored for a long time. In Dry pellets, as it is stored for a longer time, they are transported from one place to another. It contains 8-11% of moisture content. Dry pellets are of two types, one is sinking type and the other is floating type.
Protein: Mainly different breeds of fish require different amounts of protein level in their diet for example marine shrimp requires 18-20% protein, catfish requires 28-32%, tilapia requires 32-38% and hybrid striped brass requires 38-42% protein in their feed.
 Lipids: n-3 HUFA is required in the diet as a lipid for the optimal growth and health of marine fishes.
Carbohydrates: Carbohydrates are the major energy source in mammals. About 20% of carbohydrates are required in fish feed.
 Feed types: There are two types of feed available i.e. floating and sinking feed. Different breeds of fish prefer different feed for example shrimp will only eat shrinking feed. Feed is available in the form of pellets ranging in different sizes according to the size of the fish.
Medicated feeds: Medicated feeds are used when fish stop eating the feed or fall ill. Medicated feeds are used to cure fish from diseases.

Care of the breed

Care and shelter: Mainly the land which is not good for agriculture is used to make fish farms. For fish farms some points should be kept in mind such as the land should have water holding capacity, and don’t make ponds on sandy and loamy soil. If you want to do soil testing then at that land dig 1 foot wide and deep hole and fill it with water. If the water remains in the hole for 1-2 days then it is good for fish farming but if no water remains in the hole then it is not good for fish farming. Mainly 3 types of pool are there i.e. Nursery pool, Rearing pool and Production pool.

Fertilizer management: Mainly organic and inorganic fertilizers are used in aquaculture.

•    Inorganic or mineral fertilizers: They contain mineral nutrients that are manufactured in industries and material is taken from agricultural fields. It mainly includes animal manure, chicken manure and some other organic materials. Organic materials such as composts, grass, sewage, and rice bran.
•    Organic fertilizers: It contains a mixture of both mineral nutrients and organic matter. It is manufactured mainly by the local people, which includes farm animal waste and agriculture waste. It mainly consists of at least one of these plant nutrients such as nitrogen, phosphorus and/or potassium.

Care of baby fish: Remove the fish from the adult fish tank with the help of a scoop or cup. Baby fish must be given a few drops of infusoria which is a liquid diet with the help of an eyedropper several times a day. After some days when they reach half an inch in size, it is placed in the new tank which has enough space for them to grow.

Diseases and Treatment

•    Tail and fin rot: The symptoms are rotting of the tail and fin, a light white colour is seen at the corner of the fin, and then spreads all around the fin and then finally falls.
Treatment: Treatment with copper sulphate @0.5% is done. The fish is drowned in treated water for 2-3 mins.
•    Gill rot: The symptoms are gray color gills and then they finally fall. The breath of fish will squeeze and they come to the upper layer of water to take the breath and at the end, they will die due to breath squeezing.
Treatment: Fishes are drowned in 3-5% salt water for 5-10 min to treat from disease.

•    Epizootic Ulcerative Syndrome: The symptoms are ulcers on the body, fall of skin and fin and then ultimately death of the fish.
Treatment: Put 200 kg/acre of lime in water and don’t put fertilizers in the water.

•    White spot disease: White patches are seen on the skin, gills and fins of the fish.
Treatment: Drown the fish into formalin solution @0.02 % for 7-10 days for 1 hour.

•    Black spot disease: Small spots of black colour are seen on the body.
Treatment: Drown the fish into picric acid solution @0.003 % for 1 hour.

 •    Argulosis: The symptoms are slow growth, loose fin and blood spots on the skin.
Treatment: Add Malathion (50 EC) @1l/acre at the interval of 15 days for 3 times.

•    Leech: The symptoms are wounded skin and gills.
Treatment: put 1l/acre of Malathion to treat the disease.

•    Vibriosis: The symptoms are white or grey colour lesions found on the spleen and intestines.
Treatment: A dose of oxytetracycline @3-5gm/100lb of fish/day is given for 10 days or the dose of Furazolidone is given in feed @100mg/kg/fish for 6 days.

•    Furunculosis: The symptoms are darkening of the skin, enlarged spleen, rapid breathing and bloody mucous. This disease will increase the mortality among fishes.
Treatment: A dose of Sulfamerazine @150-220mg/kg fish weight/day is given for 10-14 days or the dose of Furazolidone is given in feed @25-100mg/kg fish weight/day for 10 days dose of oxytetracycline @50-70mg/kg fish weight/day is given for 10 days or dose of Oxolinic acid is given in feed @25-100mg/kg fish weight/day for 10 days.

•    Red mouth disease: The symptoms are reddening of fins, mouth, throat and gill tips.
Treatment: Several antibiotics and vaccinations are available which are used to cure red mouth disease.