Models of feed refusal syndrome in poultry.

Research on feed refusal syndrome(s), an important problem in the poultry industry, has been hindered by a lack of sensitive and quantitative laboratory models. Suitable models were developed using five groups of 30-week-old male chickens per treatment. Feed or water, depending on which was to be measured, was withdrawn overnight. Then consumption of treated water or feed was measured over a 6-hr period of rehydration or refeeding. In aqueous solutions NaCl, H2SO4, and Na2CO3 reduced liquid consumption in a dose-related manner. Ammonia caused a similar refusal when added to feed. Consumption of feed and water was not influenced by pH over the ranges likely to occur as a result of fungal activity. Consumption of feed on a wet weight, but not dry weight, basis was influenced by the moisture content of feed. A culture filtrate of Fusarium roseum NRRL 1181 containing diacetoxyscirpenol, a trichothecene mycotoxin, reduced consumption of feed by about 77% when added to feed and reduced liquid consumption by about 92% when substituted for drinking water. Thus, the models for consumption of liquids and solids appear to have the attributes necessary for quantitative investigation into the relationships of mycotoxins to feed refusal syndromes.