Efficacy of lateral ventricular injection of epinephrine, cyproheptadine, or adenosine triphosphate on feed intake in thiamin-deficient turkeys.

In previous work, thiamin deficiency (TD) resulted in decreased brain levels of adenosine triphosphate (ATP) and epinephrine, but serotonin (5-HT) was increased in the turkey. The goal of the present study was to determine whether the introduction of calculated levels of epinephrine, ATP, or cyproheptadine into the lateral ventricle could affect feed intake of TD birds. Adenosine triphosphate, epinephrine, and cyproheptadine (5-HT antagonist) were injected into the lateral ventricle of TD and control birds. These injections did not alter feed intake in the control birds. Cyproheptadine and ATP decreased feed intake in the 1st h in the TD birds as compared with sham-injected TD birds (P less than .05), but epinephrine had no effect. The results indicate replacement or inhibition of a single altered neurochemical does not increase short-term feed intake in TD birds.