Trout Fish

 Active Trout Growers

 Secretary (Fisheries) Visit to Trout Farm

Farmer’s Manual (English/Hindi) on Hygienic Preventive Measures

The trouts were introduced in the country mainly to encourage Sport Fisheries. Introduction of trouts has helped the fish to become established in most of the cold water bodies of the country. Now apart from sport fisheries, culture of trouts is increasingly being identified as a commercial venture for table fish production. Two major trouts available in our waters are brown trout (Salmo Trutta fario) and rainbow trout (Salmo gairdneri gairdneri).

These two exotic game-fishes soon established in the streams and tributaries adapting to congenial water temperature and abundance of biotic life. The transplantations provided excellent game fishing to the anglers and started attracting large number of tourists to the country. In the last three to four decades, however, a sharp decline was observed in the catches on account of multiple factors such as large scale road construction in the valleys followed be destruction of breeding and feeding grounds of the fishes, emergence of river-valley projects, rapid urbanization, fishing pressure and of course illegal and destructive means of fishing etc. The matter received serious attention of the various state governments and some states have taken steps to rehabilitate the exotic trouts in the streams as well as commercialization of trout farming in the farms.

Norwegian Assistance for the State of Himachal Pradesh

During mid-eighties a scheme was formulated by the Himachal government which inter alia gave more stress on farming of rainbow trout. The Norwegian Government came forward to assist the State Government in this endeavour and an agreement was signed during 1988 and later the scheme was put onto operation in May, 1989. The Project was split up into two phases viz. (1) transfer of technology, and (ii) production phase.

The transfer of technology (first phase) envisaged construction of modern trout farm on Norwegian model with capacity of produce 10 tonnes of trout per year. Import of quick growing disease-resistant eggs, development of economical and viable pelletized feed with locally available ingredients, training of local staff and farmers & production of economically viable fingerlings with the aim to enable the local farmers to adopt trout farming were the other aspects included under this bilateral project. The Norwegian Government agreed for financial grant of 8.00 million NOK (Rs. 3.00 crore) mainly for meeting the expenditure under consultancies, cost of equipments and training of personnel. The State Government of Himachal Pradesh agreed to bear the cost of construction of the farm, payment of customs duty and salaries of the project personnel.

Impressive Results

After finalization of the ‘ Conceptual Design Report’ during August, 1989, the first phase of the project was put into operation. The infrastructure such as raceways, circular ponds, two lines of water supply were completed by April-1990 and first consignment of ‘eyed ova’ of rainbow trout were received at Patlikuhl farm during April-1991. A feed-mill was also installed and it started producing pelletized feed with a production capacity of 500 kg. per day. Four project personnel including two women candidates underwent training during the construction phase. The results on rearing achieved during the first year of the project far surpassed the expectations of the Norwegian as well as Indian counterparts. A record survival of 92% against expectation of 42% from ‘eyed ova’ to advanced fingerling was achieved which is an all time record in trout farming in the State.

Operations

The higher survival rate virtually created a problem of storage and in order to rationalize the possible carrying capacity, 38,000 fingerlings had to be taken out of the farm and stocked in various streams viz. Tirthan, Sainj., Parbati, Beas, Gadsa etc. between Manali and Mandi. In a period of less than one year the reared fish grew to marketable size of 300 g. The second installment of eggs from Norway was received in March, 1992 and were successfully hatched. It is heartening to note that open sale of trout at Patlikuhl farm was started from third week of March, 1992. The targeted production of 10 tonnes was achieved in the first year of the project. This is significant when viewed in the context of recurring land slides and prevailing not so clear water in one of the water line alignments.

Requisite of Trout Farming

Rainbow trout requires plenitude clear icy-cold-oxygenated water. The site should be adequate to accommodate future developments likely to be required in the foreseeable future. If a constant supply of water suitable for hatchery purpose in the required volume throughout the year is not available the hatchery is sure to be a failure. It should be borne in mind that water is to be used for incubating eggs and fish of all ages. Water that is satisfactory for growing trout may not be suitable for incubating eggs and holding brood stock. Factors influencing the suitability of water include temperature, oxygen, content, pH, turbidity, mineral contents and pollution. The volume of flow including fluctuation and the elevation of the supply source above the hatchery are other important factors relative to the water supply. The source of water supply should be at least ten feet above the hatchery site. If the water is from a spring, the temperature should be uniform throughout the year. However, under all circumstances the water temperature for incubation of eggs should not exceed 10-12^o C.

Hatchery Practice

Fibre-glass hatchery troughs with Californian type of Incubators are installed. Each hatching tray should have the capacity to treat 1.5 litres of eggs i.e. about 15 to 18 thousand in number and there can be 4-7 trays depending upon the length of the trough. On the perforated Aluminum- sheet bottom of the hatching tray is kept a same size piece of Astroturf and over this is kept a plastic egg basket for laying the eggs. This plastic egg basket is removed after eggs hatch out and the alevins settle down into the Astroturf. The advantage of astroturf is that it prevents the drifting of the alevins resulting quicker absorption of the yolk sac. The eggs should be shielded from light by covers over the incubators to avoid damage by light. In the entire period, daily attention to the incubation process is needed so that (i) the dead eggs do not increase the spread of fungi (ii) malachite green bath is given to the eggs two days in a week depending upon the attack of fungus, (iii) dead eggs are removed after the embryonic eye has appeared, (iv) all egg shells are simultaneously removed, and (v) all dead yolk sac (alevins) fry are also picked up side by side. After about 75% of the yolk sac is consumed the fry is transferred to a ‘Starter Unit’ where it is fed with very small flakes of protein rich ‘start feed’. This is the most critical stage in the life of fish because if there is slight delay in feeding or the feed is not of good quality the young fish will lose its interest in feeding and start dying. After the fry has commenced feeding it is transferred to purpose-built self cleaning type of early- rearing facility. Young rainbow trout should not be reared in earth ponds due to the danger of ‘ whirling disease’. With growth of this stock, to prevent imbalance in the unit weight of this biomass, grading atleast once in hatchery and later during on-growing whenever it doubles its weight should be done. A high class hygiene level is required to be maintained if good results are to be obtained. Complete cleanness of premises, removal of dead fry, excrement and uneaten food have to be ensured. Outlets of starter units generally tend to foul with accumulation of metabolites and therefore, all drain pipes and screen be kept clean by using a high pressure hoze.

Farming Cycle

Under the technology transfer phase of this Indo-Norwegian Trout Project a production plan has been followed covering the following aspects:-

1. 100,000 certified pathogen free eyed eggs of improved strain of rainbow trout have been imported from Denmark for three years. They were incubated here and a survival rate of 92% was obtained upto the swim-up fry stage.
2. It took 195 degree days i.e. about 20 days at an average temperature of 10⁰C upto hatching.
3. The fry upto 1 g was retained in the hatchery and later shifted to nursery ponds and retained there till it acquired the weight of 5 g.
4. The stocking rate in start feeding was kept at 6kg/ M³ and in nursery at 10 kg/ M^3.
5. From 5-50 g weight the fish was shifted to smaller raceways of 5M x3 M x 1M with a stocking rate of 10 kg/ M^3.
6. From 50g to portion size of 250 g the fish was reared in bigger concrete raceways of size 15M x 2M x 1.5 M at a stocking density of 30 kg/ M³.

Technology Dissemination

Under this programme it is envisaged to provide about 4000 trout fingerlings each of 10 to 25 g weight for rearing on intensive basis up to the portion size of 250 g to the prospective farmers. About 20 sites initially for the setting up of about 35 to 40 raceways each of size 12M x 2M x 1.5 M have been selected in Kullu district. Schematic drawings of rearing units in respect of all the sites have been prepared for the guidance of the beneficiaries and added into a study report on this subject which includes a manual for the selection of sites as well as analysis on the economics of trout farming in village raceways. It is proposed to provide major inputs of trout seed and dry compound pelletized feed to the farmer besides aqua-engineering guidance to build a suitable raceway with assured supply of sufficient good quality, pollution free water throughout the farming period. The selected farmers will be provided full technical support in the shape of 2 weeks training in rearing and harvesting techniques to achieve the targeted level of productivity and a unified extension approach through our trained staff to solve their day-to-day problems. With this end in view it is proposed to set up a ‘ Training Centre’ with boarding facilities at the project farm in Patlikuhl.

A fair degree of success has been achieved in the development of an efficient and economic trout feed at the farm from raw material available within the country. Hopefully, its formulation will be soon standardized with per kilo production cost around Rs. 20/-. The objective feed conversion ratio has been kept at 1:1.5 and a production plan has been designed to raise one tonne of 200g portion size fish in one standard size village raceway in 10-12 months and is presented as Table 1.

Economic viability

In order to work out the economic viability of trout farming in village raceways by the target groups, the following parameters have been considered for analysis:

1. Two of raceways for rearing of trout have been offered. One " semi-pucca" raceway of the capacity of 30 M³ cost Rs, 15,000/-

Table 1: Expected Production plan of one tonne of portion size fish in 10 to 12 months

Month	April	May	June	July	Aug.	Sept.	Oct.	Nov.	Dec.	Jan.
Day Nos.	1	30	61	91	122	153	183	214	244	275
Temp. C0	15.0	15.0	16.0	16.0	18.0	18.0	10.0	10.0	10.0	8.0
Individual size (g)	20.0	29.0	42.0	59.0	84.0	114.0	154.0	193.0	232.0	268.0
Total biomass (kg.)	80.0	116.0	169.0	237.8	336.0	457.0	616.0	775.0	930.0	1074.0
Sum harvest (t)	0	0	0	0	0	0	0	0	0	1.074
Food req. (kg.)	-	54.0	80.09	101.9	147.4	182.3	239.0	238.0	232.0	216.0
% feeding	2.25	2.25	2.0	2.0	1.75	1.75	1.25	1.0	0.75	-

and to such raceways of the same size will cost Rs. 27,000/- 2^nd to "pucca type" of capacity of 60M³ will cost Rs. 57,000/- under the local conditions.

1. Cost of 10-25 g. average weight fingerling has been kept at Rs. 10/- per fingerling, as fixed by Government of Himachal Pradesh.
2. Optimum stocking density for ongrowing has been kept at 33.3 kilos / M³.
3. F.C.R. has been assumed as 1: 15.
4. Though labour cost of 90 days @ Rs. 22/- per day has been considered in a year but this work, too, will be done by the beneficiary.
5. Watch and ward expenditure is estimated as Rs. 500/- per month but the beneficiary will under take this job, also.
6. Repair and maintenance of the raceways and water supply channel has been assumed at 10% of the capital cost in case of ‘semi pucca’ and 5% in case of ‘pucca raceway’.
7. Interest on 80% of the capital and running cost has been worked out at 12% rate of interest.
8. It has been assumed that with the implementation of complete package of rearing practices each raceway will give a production of 1 tonne of marketable trout fish.

1. Chamba Valley,
2. Kinnaur Valley,
3. Kullu Valley,
4. Lahul Spiti Area,
5. Pabbar Valley,
6. Uhl Valley,

                          Table II:  Economics of Trout Fish Farming in Semi-Pucca Raceways