There are 6 major systems used in housing of layers.
- Free range system,
- Deep litter,
- Slatted or wire floor,
- Combination of slatted and deep litter;
- Cage or battery system.
Free Range Systems
Birds have access to an outdoor area during the day. This area may be covered or uncovered. The farmer provides an indoor area where they come in at nights and are able to roost.
Hens which are free ranged have the greatest range of natural behavior and hence have better feather condition when compared to the other housing systems. The main disadvantage is hens are exposed to toxins, wild bird diseases, predators and extreme climatic conditions.
Semi-intensive poultry housing systems
They are commonly used by small scale producers .They are characterized by having one or more pens in which the birds can forage on natural vegetation and insects to supplement the feed supplied. The farmer should provide at least two runs for alternating use to avoid build up of disease and parasites. Each run should allow at least 10 to 15m2 per hen and be fenced. A free-range allowing 40 to 80m2 per hen is required where the hens are expected to obtain a substantial part of their diet by foraging.
Small simple poultry house
The house allows 0.3 to 0.4m2 per bird. It has thatched roof, a littered earth floor and slatted or chicken wire walls on at least three sides to provide protection from rough weather, from predators at night and offer shade in the day time. The shelter should be large enough to enter to collect eggs and be equipped with nest boxes, feeders, drinkers and perches. For convenience the house should be situated so that access to each of the runs can be provided with small outlet doors.
A shelter for roosting and lying can be used in combination with daytime foraging by the hens. The legs of this structure have rat guards (keeps off rats) and ant protection and may be equipped with skids or wheels to make the whole unit easily movable between runs. Feed and water are provided in troughs outside the house.
This system is low in cost, but growth of the birds and egg production are likely to be less than with systems offering closer confinement and better feed. Losses may be encountered by birds of prey and from failure to find eggs laid in bushy areas. The poultry run requires a considerable amount of fencing.
A fold unit is a house and run combined, having part of it covered with chicken wire and the remainder with solid walls. The unit should allow 0.5m2 per bird and must be moved each day over an area of grassland. A unit 6 by 1.5m will take 16 to 18 birds. For larger flocks several such units are required.
Portable units are generally more expensive than permanent houses and may decay quickly because of contact with the ground. Hens have reasonable protection against bird of prey and rough weather and parasites if the unit is not returned to the same area within 30 days.
Deep litter housing system
In this system the birds are kept in litter floor. Feed, water and nest are provided inside the house. Fresh and suitable litter materials spread on the floor include: paddy husk, saw dust, ground nut hulls, chopped paddy straw or wood shavings .The litter material is of about 3to 5 inches depth. The litter saves labour involved in frequent cleaning of fecal matter (droppings), however it needs periodical stirring replacement. The litter is spread on the floor in layers of 2” height every fortnightly till the required drying is achieved.
The birds are confined and well protected. Has low masonry walls set on a concrete floor and wire mesh on the upper part of the walls. The building excludes rats and birds.
Rough cast and other materials can be used for the walls. The house can be designed up to 9m in width and any length that is needed. The density of birds is approximately 4 to 5 birds/m2 of floor area.
As an advantage of this system, Vitamin B2 and Vitamin B12 are made available to birds from the litter material as a result of the bacterial action. The deep litter is used for manure on disposal .There is lesser irritation from flies when compared to cage system.
Since there is direct contact between bird and litter, bacterial and parasitic disease may be a problem. Respiratory problems may arise due to dust from the litter. The cost of litter is an added expense on production cost. Error in ventilation can have more serious consequences than in the cage system.
Slatted or wire floor housing system
Wire mesh or wooden slatted floors are used instead of deep litter. The house can be built on treated wooden piers 0.8 to 1m above the ground. Ventilation and manure removal are both facilitated and bird density can be 6 to 8 per m2.
A thatch roof or corrugated iron roof may be used with the roof space about 1.5m above the floor. Some insulation under the roof is required.
The feed troughs should be equipped with hinged covers and rat guards should be installed at the top of each pier. The width of this type of building should be limited to about 2m to allow easy removal of manure and adequate wall space for feeders and nests.
The building should be oriented east and west and may be of any length. However, if it is more than 5m long, nests will need to be put on the sides and all remaining wall space on either side used for feeders in order to allow the required 100mm/bird.
If using a slatted floor made sufficiently strong for a person to walk on, then a wider building is possible as feeders can be placed completely inside where the chickens have access to both sides of the trough. The floor is sectioned for easy removal during cleaning out of manure. This type of houses is cooler than other types, but the building cost is high and management is more complicated.
Combination of slatted floor and deep litter
A combination of deep litter and slatted floor house, offers some advantage over simple deep litter house, but with some increase in investment. Approximately half of the floor area is covered with small gum pole boards or with wire mesh. This area is raised above the concrete floor 0.5m or more so that cleaning under the slatted portion may be done from the outside. Waterers and feeders are placed on the slatted area. This type of house is limited in width to 3 to 4m so that feeders and waterers can be handled from the litter area and manure beneath the slatted area can be easily removed from the outside without moving the slats or disturbing the birds. Although this system entails added expenses for materials and labour to install the boards/slats, the bird density can be increased to 5 to 7 per m2, so there is little difference in the cost per bird.
This system saves on litter, increases litter life, reduces contact between birds and manure, and allows manure removal without disturbing the hens. Ventilation is improved due to the slatted floor. Possibly the biggest disadvantage is the limited width for convenient operation and the need for some litter.
In medium to large scale houses of this type the slatted floor must be made removable in sections and at least part of it made strong to walk on. This will result into increased building cost and a more complicated management. The house shown has slats over 2/3 of the floor area. This is generally considered maximum for this type of house and allows for stocking density of up to 8 birds per m2. Automatic tube feeders are placed on the slatted floor. One such feeder, with a bottom diameter of 0.6m can serve for 60 to 75 birds, depending on size of breed.
The water troughs are suspended from the ceiling. The nest boxes are doubled by arranging them back to back and have one end resting on the slatted floor and the other suspended from the ceiling. Egg collection can be facilitated by use of a trolley, which is supported on a rail just below the ceiling. Cleaning out between batches can be done by a spade, if all furnishings and part of the end walls are made removable.
Cage or battery systems
In cage system poultry are reared on raised wire netting floor in smaller compartments, called cages, which could be fitted with stands on floor of house or hanged from the roof. It has been shown to be very efficient for laying operations, right from day-old to disposal. Currently, 75% of commercial layers in the world are kept in cages. They consist of rows of stairs-step cages in long narrow shelters. The thatch roof or insulated metal roof shelter can be completely open on the sides with perhaps some canvas curtains in areas where cold winds are experienced. The building should be oriented east and west and designed to provide shade for the cages near the ends.
A 3.4 metre length will allow for four cages without overlap and passageway of about 0.9m. While cleaning is easily achieved on a concrete floor, smooth hard soil is less expensive and quite satisfactory. A little loose sand or other litter spread on the soil before the manure collects will make manure removal easier. The building posts should be treated with wood preservative and well-built enough to support the cages. Rat guard should be installed on the posts at a height of 0.8 to 1m. A central passage, raised 20cm and cast of concrete is easily cleaned and keeps manure from encroaching on the work area. Feeding and egg collecting are easily done by hand or with an automatic system. Ensure that watering trough is carefully adjusted so that all birds receive water. The simplest method of supplying water automatically or by hand at one end is to slope the entire building and row of cages 10mm/3m of length.
Feeders and waterers are attached to cages from outside except nipple waterers, for which pipeline is installed through or above cages. Auto-operated feeding trolleys and egg collection belts can also be used in this rearing system. The droppings are either collected in trays underneath cages or on belts or on the floor or deep pit under cages, depending on type of cages.
Cage types that are equipped with pans to catch the manure are not advocated because they restrict ventilation. Previously used cages should be considered only if they are of suitable design, and have been carefully inspected for condition prior to purchasing.
Cage system needs minimum floor space. It is possible to collect more number of eggs per hen. There is less feed wastage and better feed efficiency. The system provides protection from internal parasites and soil borne illnesses. Sick and unproductive birds can be easily identified and isolated. Clean eggs production. Vices of egg eating, pecking among others is minimal. Broodiness is also minimal. No need of litter material. Artificial Insemination (AI) can be adopted.
The system incurs high initial investment cost. Also handling of manure may be problem. Flies become a greater nuisance. The incidence of blood spots in egg is high. The poultry develop problem of cage layer fatigue. (Laying birds in cages develop lameness. It may be due to Ca and P deficiency but the exact reason is unknown).