LPM 221: Commercial Poultry Production and Hatchery Management (1+1)

ALLEVIATING MEASURES

• The above adverse effects due to high environmental temperature can be overcome to a considerable extent by proper management of the flock, house, feed etc. during summer, as indicated below:
  • By proper roofing, the temperature inside the poultry houses can be kept at 5^o - 10^oC below the outside temperature.
  • Thatched roofing of about six inches thickness provides optimum comfort to the birds during summer, than any other roofing material. However, due to the risk of fire, less durability, more depreciation and rodent problem, thatched roofing is not preferred, especially by large farms.
  • In large farms, aluminium roof is preferred due to its durability, resale value and rear reflecting properties.
  • In case of non-insulated houses, the roof must be raised to a sufficient height from the floor level; because higher the roof, cooler will be the poultry house.
  • The minimum height between the floor and the roof must be 4.0 and 3.5 metres at the ridge and eaves, respectively.
  • The eaves at the roof shall project out atleast one metre on all the four sides as over hang to prevent direct sun light and rain water entering into the house.
  • Provide "ridge-ventilation" such as "half-monitor" or "full monitor".
  • Further, where the summer is very severe, the roof may be insulated either by covering with a layer of thatch or by painting the upper surface of the roof with a white paint such as white water proof paint, or aluminium paint, to reflect the sun's rays back and the inner surface may be painted with a black paint or tar to absorb the heat from within.
  • In tropics, in order to prevent direct sun light falling into poultry houses, the long axis of the houses have to face north and south i.e. the houses must be orientated east to west; with a slight tilt towards southern side in the east and towards north in the west. This type of orientation also prevents severe drafts and rain water sprinkling into poultry houses during monsoon.
  • Open type, cross-ventilation is recommended in tropics. Except for a 20cm height wall, all the four sides upto the roof should be provided with 12mm size and 18 gauge chicken wire mesh or 25mm size chain link mesh.
  • As far as possible the width of poultry houses shall not exceed 10 metres. If the width of the poultry house exceeds 10 metres, cross-ventilation alone may not be effective in providing proper air flow in poultry houses. In such cases, also provide "ridge-ventilation" in the roof or mechanical ventilation.
  • Provide tunnel ventilation along with pad coolers and/or foggers, to produce evaporative cooling.
  • During hot summer, this mechanical ventilation, with evaporative coolers should be functioning from 10 A.M. to 6 P.M. However, the evaporative coolers will be less effective in highly humid areas.
  • Sprinklers may be fixed on the top of the roof and operated continuously from 10 to 18 hours, to cool the roof.
  • Foggers may be fixed inside the broiler house and operated during hot and dry weather, to produce evaporative coolness.
  • Grow "fast-growing" shady trees around poultry houses in order to reduce the severity of the summer heat waves and also to break wind drafts during monsoon.
  • Rear relatively more heat tolerant strains of broilers suitable for tropical climate.
  • During hot weather, birds consume twice the amount of water than that is normally consumed. Therefore, double the watering space in poultry houses during summer. Provide plenty of fresh, clean and cool drinking water during hot weather. The water pipes should not be exposed to sun light. Change the water two or more times a day, if it gets heated up.
  • In order to encourage the feed intake of birds during summer, reduce the energy content of the feed by about 10 percent.
  • It is also advisable to provide an addition of one or two percent protein and slightly increase the levels of vitamins, minerals, and essential amino acids and coccidiostat.
  • Since feed consumption generate more body heat, avoid feeding broilers over four weeks of age, during hot weather.
  • If automatic winchable feeders are used, lift the feeders between 9 and 18 hours. To compensate this loss in feeding hours, feed broilers using night time and cooler hours of the day.
  • Nearly 10 to 15% of the calories (energy) in the feed, of carbohydrate and protein origin, may be replaced by fat /oil energy, by adding 2 to 3% oil or fat. But this should not increase the total calories in the feed and only replace the energy of carbohydrate origin.
  • Large farms in hot and dry climate may opt for environmentally controlled poultry houses.
  • Drugs and chemicals like electrolytes, ascorbic acid, sodium bicarbonate, tranquilisers, sodium salicylate, paracetamol, chlorpromazine hydrochloride, cyproheptadine hydrochloride may be administered through feed or water, to make the birds to withstand hot weather.
  • Thick and wet litter produce/ generates more heat. Therefore, during summer, the litter thickness must not be more than 6cm. Moreover, remove caked up and wet litter immediately from the poultry house, to stop excess heat production.
  • Avoid over crowding. Increase floor space by atleast 10% during summer.
  • If mechanical ventilation is provided, increase the air flow rate and air exchanges by atleast 25%, during summer.
  • Do not disturb the birds and make them panic during hot weather.
  • For birds kept in cages, the centre height of building should be a minimum of 14 feet.
  • Addition of 0.48 percent potassium chloride to water lowered heat stress in layers.
  • Add 1kg of sodium bicarbonate to one tonne of feed to lower heat stroke and to increase shell thickness.