The effects of Clostridium botulinum toxin type C beta given orally to goats.

Feeding experiments with Clostridium botulinum toxin type Cβ were carried out using 11 goats. The toxin, which originated partly from the liver of a cat carcass and partly from broth inoculated with Cl. botulinum type Cβ isolated from the cat liver, was given to the goats through a rubber stomach-tube. Symptoms of botulism usually occurred on the second or third day after the challenge. Death was caused by doses of toxin as small as 0.5 MMLD (minimum mouse lethal dose) per g body weight of goat, and 1 MMLD per g was considered to be lethal for goats when they are fed hay and concentrated fodder. When the animals were grazing or received ensilage they seemed to tolerate somewhat higher doses. A cumulative effect was shown to take place when the doses of toxin were given in the course of 8 days. A sensitizing effect of many small doses could not be demonstrated. On the contrary, animals which had received several small doses of toxin later on tolerated doses which caused death in inexperienced animals. One of these animals tolerated a dose approx. 3 times higher than a dose usually causing death. Serum from such goats, however, did not give demonstrable protection in mice challenged to botulinum toxin type Cβ. Toxin could not be demonstrated in samples of serum from goats showing symptoms of botulism. In 2 of 9 animals toxin could be demonstrated in samples from the liver, but only after the liver had remained in the carcass for approx. 20 hrs. after death.