High temperatures are a serious problem for all types of poultry.
Heat stress has a negative impact on the production of eggs, size of eggs, feed consumption,
growth rates, hatchability, as well as causing deaths of birds. Therefore we can not prevent the formation
the heat in the house, and high temperature, created by the birds should be kept
to a minimum.
This article describes, as heat stress affects the bird, and provides ways
reduce the impact of heat stress on poultry productivity.
As broilers respond to heat stress?
At high temperatures, the bird often changes behavior, which allows it to recover
heat balance. During the hottest periods of the birds to rest more. Some birds lean against
wall or pipe drinking system. At high temperatures, often air shortage. In it
while increased activity of muscles and, Consequently, It increases energy expenditure.
Lack of air usually occurs, when
temperature reaches 30oC.
broilers, as well as other poultry, difficult to tolerate a high temperature at high
Deaths due to heat exhaustion occurs very often, especially in birds with more weight.
As the lack of air affects the pH or acid-alkaline balance of broilers?
Generally, the blood pH is controlled by the kidneys and lungs by various buffer systems, that
preventing rapid changes in pH. With an increase in respiration rate in broilers, exposed
heat stress, a reduction in carbon dioxide levels and occurs respiratory alkalosis
(elevated blood pH). Heat stress also reduces the level of potassium and other minerals in the
the body, changing the balance of the body electrolytes.
Does a decrease in feed intake during heat stress?
Upon the occurrence of hot period decreases food intake. This is part of the physiological adaptation
bird stress. Reduced feed intake flows into the reduction of the daily intake of nutrients
matter, which are responsible for growth. but, if the body receives a smaller amount of nutrient
matter, it means he spends less energy on digestion. In this way, although the pace is slowing
growth, Birds can now easily transfer heat. Studies show, that the number of surviving
broilers reduced, if increases feed intake during heat stress, especially during
the hot periods of the day.
How can I alleviate heat stress?
Several characteristics of the building, such as its location, amount of insulating material,
number of roof projections greatly influence the temperature inside the building. Location of the building must
be so, to be able to take advantage of prevailing winds and thus, to the sun
not shine directly into the building.
If during the construction of the building is not a set of isolation was carried out, this can be done later, what
It will help prevent the influence of the solar heat on the temperature inside the building.
Insulation will be useful and in the cold season, as it retains heat. The correct length
Roof projections also do not allow sunlight into the room. In buildings with isolated
ceilings ventilation system must be installed on the ceiling. Additional
ventilation system will also help to avoid problems with high humidity in winter.
Ventilation and Cooling
Proper ventilation is necessary to reduce the temperature in the house. Birds do not sweat and lose
heat through the respiratory tract, earrings, and areas without feathers under the wings. Increase circulation
Air helps birds get rid of excess temperature.
In poultry houses without automatic ventilation valve must be installed, to provide
maximum air flow. With proper ventilation air flow
It will be distributed in the center of the house, as it shown on the picture 1.
Nothing should prevent air flow.
In houses with shutters, located on the sides and tunnel fans to improve
ventilation, the height of the ventilation system valves and controls should be coordinated for the
amplification airflow (Drawing 2). There may be needed
fans to create air movement inside the building.
• In houses with natural ventilation, make sure, that the intake valves are fully open and
the air flow does not block high grass, that grows near the poultry house. Mow the grass around
the house and make sure, that it is no more 15 cm in height within 15 meters from the house. branches
trees, that hang too low, should cut down.
• Remove transport, оборудование, garbage, which may reflect the heat in the poultry house. grass clippings
around the house will reflect a minimal amount of heat aviary, than the bare ground. Extend
projecting roof overhangs, if you want to avoid direct sunlight into the building. AT
houses with self-ventilated, clean the fan and make sure, the whole system
It is functioning properly. Make, that the fan belts well fixed and the fan blades
• Clean the air vents and check, the air vents are not obstructed.
• Set the thermostat so the ventilation system, to all the fans worked continuously on
During the hottest periods of the day.
• The ventilation system must be operated throughout the night. Room cooling at night
It helps the birds easier to endure the heat of the day.
• If you do not have fans, set them. Make, that the protective grille guard
fan is in good condition. Before installing the fan, check, will
electricity system to support additional load.
• Blanch the ceiling or color reflective paint, especially in the non-insulated poultry houses. This
procedure will help reflect heat, but it is not effective to cool the building. use
the following solution: 9 kg slaked lime per 19 l of water 1 l polyvinyl.
• If the wrong roof insulation, use the system for spraying the roof. Make, what
the system is installed correctly. Check the amount of, to determine whether the lack of water for drinking and birds
roof spray. In the first place should be enough water for drinking.
When the cellular content of the following, staplivalsya to avoid droppings of birds in cages.
Litter impedes air flow and forms a further heat from the natural
the decomposition process.
Cooling by evaporation
Cooling by evaporation can significantly help the bird to move heat. limiting factor
System - is an external humidity, since the evaporation rate determines its effectiveness. AT
by evaporation cooling system using hot air to evaporate water. This increases
relative humidity, but reduces the temperature of the air. The most effective system
air-conditioning - a system, wherein the entire fresh air passes through the wet panel
cooling. When properly designed, system will reduce the air temperature to 11 degrees.
for example, at 38 ° C and 30 % relative humidity air can be cooled to 27 ° C. The system can
It is used in areas of high humidity, since the humidity levels are reduced to very low
levels during most of the hottest periods of the day.
Another type of air conditioning system is a misting system. The system uses high
pressure to create a fine mist inside the building. studies show, that blurred
may increase the efficiency of the ventilation system 50%. Here it is necessary to monitor, that
litter becoming too wet.
Feeding and watering
The drinking system
It is important to provide the necessary amount of water birds during hot periods. Expansion
Drinking front bird floor maintenance and increase in the number of drinkers will help increase
water consumption. Should be considered, that the birds will not drink warm water so willingly, as
• Increase the front watering especially for parents and broilers. Fill the fresh water in the drinkers
the hot periods of the day, to the birds was a sufficient amount of cool drinking water.
• Increase the feed rate and the amount of water in the drinking systems.
• If the drinking system has a filter, it should be clean and not to impede the movement of the water.
• Flush closed the drinking system. Water in plastic pipes in closed systems the drinking
rapidly reaches the temperature around the tubes.
Increased water intake during heat stress will increase the ratio of the surviving birds. Many
researchers attribute the increased survival rate of birds, who received additional salt such as potassium bicarbonate, potassium chloride, sodium chloride, chloride
ammonium, increased water consumption, instead of salts.
How useful hungry exposure during heat stress?
feed intake should also be given attention during hot periods. Typically, feed intake
declines and the birds can not get enough nutrients, necessary for
growth and produce performance indicators at the desired level. Often, manufacturers are trying to
stimulate feed intake during hot periods, however this can backfire.
Excessive food intake will increase the bird's body temperature and, perhaps, lead to more
case. Hungry exposure during the hottest periods reduces the thermal load and increases the percentage of
survival. Golodnaya extract reduces the production of heat through digestion, absorption and metabolism
nutrients. When the bird movement involves the work of muscles, that generates additional
heat. In a hot environment, this heat production only increase the heat load. Следовательно, that
reduce the heat load of poultry must be kept alone. It is necessary to stop feeding, if
temperature exceeds 32 ° C. Feeding can be stopped, closing the trough or raising them. make
it is necessary as soon as possible, to the gastrointestinal tract was empty by the time, when
house temperature reaches 32 ° C. Birds should not be fed until, temperature drops below
32° C night. However, this technology should not be used continuously, since growth rates are
reduced. Technology should be used only in emergency situations.
Heat stress reduces feed intake in broilers, a, Consequently, and the amount of nutrients
matter. therefore, feed formulation should be changed, Considering that, that the feed intake will
reduced. It would be wrong to increase the concentration of only protein. It should also be increased
energy diet, as well as, other nutrients. It is also important to increase the concentration of the fatty
acids and recalculate the concentration of vitamins and minerals. The use of vitamin C, as
antistressovogo preparation, it is often important during heat stress.
It is also very important to choose the right kotsidiostatik, an antioxidant and a mold inhibitor for feed,
stored in a warehouse. Not carbohydrates or fats, and promote the production of larger proteins
metabolic heat. Следовательно, unbalanced diets lead to increased
metabolic heat production. The balance of amino acids is very important in the diet. At this time should be
develop diets with slightly lower protein levels and apply large quantities
synthetic amino acids, especially methionine, lysine and threonine.
Remove other sources of stress
• Reduce stocking density of birds
• Do not disturb the birds during hot periods.
• Do not debikiruyte bird, while the temperature is not below.
• Birds should move as little as possible.
poultry in a comfortable environment for it is essential during hot periods.
Broilers under heat stress exposed to severe physiological changes. decreases
feed intake and increased water consumption, therefore necessary correction of the diet, which
reduce metabolic heat production and keep the intake of nutrients at the appropriate
Ensure good ventilation and use of water in the required amount.
Reducing the activity of the birds during hot days will reduce the thermal load. Controlled
hungry exposure often helps to increase the survival rate of birds during heat stress.
Good care of the bird and prepare the house, correct feeding and watering program
help to minimize deaths and stress, caused by high temperatures.
In the struggle with the heat stress our company can recommend you medication Reevit c Plus.
Reevit c Plus when used properly, can significantly mitigate the effect of thermal stress on the herd of animals and birds