System of Housing Broilers and Layers
Systems of housing
The broilers may be raised on deep litter, in cages or in batteries with slatted or wire floor system. Deep litter system of housing is the most widely used system for broilers.
Layers are reared on deep litter floors, in cages or on different kinds of floors at different ages. Deep litter floor rearing involves rearing egg-type chicks or birds on any one of the preferred litter materials (paddy husks, groundnut hulls, wood shavings, etc.) spread on the floor. Cages of different sizes with different sized meshes need to be fabricated for rearing layer chickens of different ages.
Buildings involve are the major capital expenditure and therefore need thorough planning. The various types of buildings required on a broiler farm are:
Staff or watchman quarters;
Burial pit or incinerator.
Broilers need houses to protect them from extremes of climate, theft, predatory animals like wild cats, dogs or bandicoots, etc. to ensure easy and better management, to facilitate automation and to provide ideal, comfortable rearing conditions.
Optimal environmental conditions for rearing broilers
Temperature: 22-30oC (or) 70-85oF;
Relative humidity: 30-60 per cent;
Ammonia: Less than 25 ppm;
Litter moisture: 15-25 per cent;
Airflow: Open-sided houses with 35 cm high sidewalls and breadth of broiler houses restricted to 7.2 m; otherwise, airflow should be 10-30 metres per minute by turbo-ventilation.
The broiler houses should be oriented with their long axis in an east-west direction to avoid direct sunlight falling into the building.
The rule of thumb is that the long axis of the houses should be parallel to the shadow of a vertically erected pole during the hottest summer.
The floor-level of broiler houses should be raised 30 cm (one foot) above the outer ground level to prevent seepage of water into the house.
The floor should be made of cement concrete to prevent damage by rodents and to permit easy and efficient cleaning and disinfecting.
Mud floors and sand floors should never be permitted, as they will render cleaning between batches very difficult and will harbour micro-organisms, eggs of parasites, etc., which may cause outbreaks of disease in subsequent batches.
The width of open-side broiler houses should not be wider than 7.20 m or less than 4.80 m to permit optimal cross-ventilation.
The length of the house may vary depending on the required capacity and the length of the available land.
In tunnel-ventilated broiler houses fitted with automatic feeders and drinkers, the width may be upto 12.00 m.
The long walls on the sides should not be more than 35 cm high above the floor level, with the rest of the area covered with a mesh.
Open-sided broiler houses are preferred because of the tropical conditions prevailing in the region.
The top of the sidewall should be tapered sloping downwards to avoid young birds perching on the walls.
The wall should be thoroughly cement-plastered and well watered to avoid cracks forming. In places of extreme climatic conditions, the walls may be constructed with hollow bricks for an insulating effect.
The space between the top of the sidewall and the roof must be covered with wire mesh (1.25 X 1.25cm, 20-22 gauge thick), weld mesh (2.5 X 5.0cm, 12-14 gauge thick) or chain link (2.5cm, 12 gauge). It should be durable and strong and close enough to prevent the entry of rodents and predators.
The doors may be fitted with strong G.I. rod supporting-frames of weld mesh at 8-10 m intervals, each one metre in width.
The roof may be thatched (straw, coconut leaves or palmyrah leaves), tiled or covered with lightroof (asphalt or bitumen), asbestos or aluminium sheets. Thatched roofs are cheaper, but less durable and may leak.
They provide a cooler environment during the hot summer.
To prevent leakage, the slope of thatched roofs must be steeper. Asbestos or aluminium roofs are durable, but more costly.
As houses with these roofs remain hot during summer, the height at the ridge should preferably be about 4.0-4.5 m.
Tiled roofing is good for low-capacity farms, and asbestos roofing for larger farms.
The broiler houses can also be two-storeyed, with the lower floor having a concrete roof which will serve as the floor for broilers raised on the first floor.
The height of the roof should preferably be 2.40-3.00 m at the eaves, and 3.60-4.50 m at the ridge. Thatched roofs may have a lower height of 1.95 m at the eaves.
The projection of the roof at the eaves (overhang) should be at least 0.90-1.35 m on either side to prevent direct sunlight and the splashing of rainwater into the buildings.
It is better to adjust the overhang to be half the length between the eaves and the top of the sidewall (the height of the area covered by weld mesh).
In regions of extreme climatic conditions, it is very useful to have the roof insulated.
Insulation may be provided by a bed of straw on the top of the roof, or by having false roofing at the level of the eaves in the form of mats spread to cover the entire roof area.
Plywood, coir or hardboard as a covering can also be useful. The roof may also painted white with aluminium paint to reflect the sun's rays and thereby reduce the heat build-up within the house.
In areas where the summer is severe, it is better to have-roofed broiler houses, or to provide ridge ventilation at the roof.
Chimneys can also be provided on the roof at intervals. In areas where winter is severe, it is advisable to have square-shaped broiler houses which expose a smaller area and help to conserve the heat produced by birds within the building.