Written by Dr. Balkar Bains
Third Quarter Syndrome
Third Quarter Syndrome (TQS) refers to the three month period from July to September when environmental changes adversely affect the economic performance of the poultry industry, especially broilers. This condition has consistently occurred for several years in broiler chickens, with the same economic losses repeated during the same three month period. The economic cost of TQS is significant, despite attempts to identify and find a solution to the problem.
Mycotoxins – the enemy
All observations to date indicate mycotoxins play a key role in the incidence of TQS. The third quarter brings in more hot and humid conditions that coincide with the corn harvest in South East Asia. Corn harvested during hot and humid conditions is often contaminated with various mold species. Because of its high energy value feed mills use corn in preference to wheat, sorghum or barley in poultry feed. Mycotoxins usually survive the feed milling process and will therefore be ingested by chickens via the feed. The most common molds are Aspergillus spp that produce aflatoxins which impact negatively on chicken health and metabolism e.g.:
1. Depending on the levels of aflatoxin in feed, nutrient absorption from the intestine may decrease, particularly most B group vitamins. Poor metabolism in turn reduces growth rates and feed conversion efficiency. A supplement of B vitamins via drinking water for a short period of one week deserves consideration.
2. Aflatoxins suppress immune response to infections like Infectious bursal disease and coccidiosis.
3. Aflatoxins decrease egg production and hatchability.
TQS and gut health
Hot and humid conditions in conventional broiler houses brings on heat stress in birds. During heat stress, chickens eat less feed and drink more water. Chicken droppings pass more water and chickens exhale more moisture in the broiler house. Lower feed intake means also that anticoccidial dosage intake by the chicken will also be reduced and thus triggers the possibility of subclinical coccidiosis. Subclinical coccidiosis will certainly cause intestinal cell damage and the dead and dying cells becomes a media for growth of Clostridia. Toxins produced by Clostridia will lead to the development of necrotic enteritis.
How to control TQS?
TQS begins with contamination at corn production and storage sites and that contamination is passed on to feed mills and then on poultry farms. The best option to control TQS rests with the corn supply source, to eliminate corn contamination with molds and aflatoxins. The use of toxin binder in the feed is an option highly recommended. At the poultry farm monitor subclinical diseases like coccidiosis, enteritis and heat stress that may persist without clinical signs. Be prepared to revise anticoccidial and antibacterial programs to properly manage the disease challenges brought about by TQS.