Antiurease Formation in the Hen

Abstract

Although urease is very toxic when injected into mammals it has very little effect upon the hen unless urea is injected simultaneously. This is to be accounted for by the low urea content of hen's blood, which has been found to be about 1 mg. per 100 cc., or even less, in the 8 hens tested. From 800 to 17,000 units of urease were injected at one time, into a wing vein or directly into the heart. The white leghorn hens were observed following the injection and samples of blood and feces were analyzed for ammonia, urea, uric acid and urease. The injected urease disappeared from the blood within 4 hours after the injection and did not appear in the feces. Following injection of urease the blood urea disappeared entirely, its place being taken by ammonia. The uric acid content of hens' blood (2.0-4.0 mg. per 100 cc.) was not apparently affected by destruction of the urea, as might be expected if urea were a necessary precursor of uric acid. Examination of the feces showed that the reaction becomes slightly alkaline after the injection of urease.

Antiurease was formed in 8 hens by 4 to 10 injections of urease (each injection containing from 500 to 5,000 units) over a period of 30 to 50 days. Antiurease could be demonstrated in the blood about 14 days after the first injection. There was an incubation period of 7 days after the last injection. The amount of antiurease found in the hens, as determined by the method of Kirk and Sumner, 1 varied between 5 and 24 antiunits per cc. of serum. The chicken antiurease which has been obtained is similar to rabbit antiurease.