Boehringer Ingelheim Vetmedica Inc. (BIVI) has placed a voluntary stop sale on its conditionally licensed Corynebacterium pseudotuberculosis bacterin-toxoid vaccine, more commonly known as the "pigeon fever vaccine."

A written statement from the company said the voluntary stop sale, which took effect April 9, "is due to reports of unexpected post-vaccination gastrointestinal tract events observed in some horses. During the required pre-licensing safety studies, these events were not observed.

"We are committed to supplying the highest quality products to our customers and believe a voluntary stop sale is in the best interest of our customers and their horses," the company’s statement said.

The statement indicated that an investigation into these events is underway.

Direct medical and technical questions to BIVI’s veterinary technical services team at 866/638-2226, Monday through Friday from 8 a.m. to 5 p.m. central time, the statement said.

"We are fully committed to providing veterinarians and horse owners with the highest quality products for horse health and to researching and developing products that will offer horses protection from current and future diseases and conditions," BIVI’s statement concluded.