The effect of heat stress on broiler performance and strategies to reduce this effect
Published:May 22, 2019
Summary
Heat stress in broilers can be defined as the result of metabolic, hormonal, and immune system changes suffered by the birds when they are unable to dissipate sufficient body heat to the environment due to unsuitable conditions. Increases in environmental temperature and relative humidity are key components in this phenomenon. Broilers need different environmental temperatures at different age...
Could you please provide a reference for the following statement:
Exposing young birds to high temperatures can condition them to survive high temperatures when they are older. This procedure consists in raising the temperature in the broiler house to 37 °C for a few hours every day between 5 and 7 days of age. Acclimatised birds will survive better if high temperatures occur after 30 days
Thank you.
Dr. Mike Czarick
I believe this refers to broiler work conduced at Virginia Tech by Drs. Weaver and Denbow by their student Arjona. Other work was completed by a visiting researcher from Israel by the name of Cahaner. Other work was completed by Frank Eden an others in turkeys, but I don't think it was successful in showing a response.
References:
ARJONA, A.A., DENBOW, D.M. and WEAVER, W.D. (1988) Effect of heat stress early in life on mortality of broilers exposed to high environmental temperatures just prior to marketing. Poultry Science 67: 226-231. CrossRef | Google Scholar | PubMed
CAHANER, A. and LEENSTRA, F. (1992) Effects of high temperature on growth and efficiency of male and female broilers from lines selected for high weight gain, favorable feed conversion, and high or low fat content. Poultry Science 71: 1237-1250
Thank you for this very informative article Antonio and Jose.
Could you kindly provide a reference for this statement.
"..Intestinal integrity is weakened because there is not enough energy to produce the proteins that form the tight junctions between the enterocytes during this stage of the process. This enables enteropathogenic bacteria to translocate from the gut lumen to the blood systemic system, making infections more likely"
Thanks. .
Dear Authors, Thanks for providing good information to overcome the heat stress in Broilers.
Further to this I like to add that supplementation of Sodium Bicarbonate (NaHCO3) @ 0.4% in feed or (0.2% by weight) in water is helpful during heat stress in broilers.
Actually panting of birds to fight with high temperature causes loss of Carbon dioxide (CO2) and Respiratory Alkalosis raises pH of blood of affected birds. Addition of NaHCO3 maintaining the pH and birds feel comfortable.
For further details, the article of Dr. Dunny Hooge, Ph.D., read in March 2000 issue of Feed International may be studied.
Could you please provide literature on the following statement;
"Restricting feed to 60% of normal consumption during days 4, 5, and 6 of life has been proven to reduce mortality if temperatures are high in the late stages of production."
Dr. Mehmet Kuran I'm really wondering how is that successful? I guess If we apply feed restriction they are going to have more suffering. I know that a lot of farmer and companies using "night feeding" during the summer period to preserve egg production at layering but I never read or heard that feed restriction during heat stress.
Betaine and Betaine HCl have been used successfully in many markets to mitigate the effects of heat stress in poultry, swine, and ruminants. Supplementation at ~0.1% in broilers effectively reduced body temperature, respiration, energy requirements, and helped maintain optimal metabolism and gut integrity.
