Over the past several months, Dr. John Angelos of UC Davis School of Veterinary Medicine has been working on a vaccine for one of the cattle industry's most widespread diseases: infectious bovine keratoconjunctivitis (IBK), commonly known as pinkeye. IBK is caused by an infection of Moraxella bovis in the eye that leads to corneal ulcers, scarring and, in extreme cases, permanent blindness.
According to Dr. Angelos, the disease presents an economic loss for the producer due to the cost of labor to treat the infection, the cost of the antibiotic treatment as well as reduced weight gains. He also notes the disease has certain animal welfare considerations; it can be extremely painful for the infected animal. Currently, there is not an effective vaccine to prevent the painful disease, only a costly treatment.
Dr. Angelos has been working on this vaccine since April, but the vaccine has been developing since the early 2000s. This summer, Dr. Angelos is testing the effectiveness of an intranasal vaccine, rather than the subcutaneous version of previous studies. His hypothesis states “calves vaccinated intranasally with Moraxella bovis cytotoxin (MbxA) will have a significantly reduced cumulative proportion of corneal ulcerations associated with naturally occurring IBK versus control calves.”The team collected blood and tear samples from approximately 180 animals at the UC Sierra Foothill Research and Extension Center and administered either the vaccine or a placebo assigned to the animal. In order to keep the results unbiased, Dr. Angelos did not know which vaccine he was giving to the animals; they were labeled “A” or “B.”
Each week thereafter, he and several students have examined the entire herd, noting those with active cases of pinkeye. If an animal shows signs of pinkeye, an innocuous stain is administered in the eye to see the ulcer, a measurement and a picture are taken to monitor the ulcer from week to week. At the end of the study, animals with active cases of pinkeye will be given antibiotics to cure the pinkeye.
Ultimately, the goal of the research is to create a vaccine that will prevent the disease from occurring. Dr. Angelos explained that although this vaccine has made great advancements, it will need to have subsequent testing and trials to determine if it is viable in the industry. In the video below, Dr. Angelos explains his research and the role of the Sierra Foothill Research and Extension Center in developing a vaccine for infectious bovine keratoconjunctivitis.