I am a Veterinary Graduate from the Universidad Nacional Autonoma de Mexico. As my first job, I have been hired by the LaLa dairy cooperative in Torreon, Mexico. My job responsibilities will be to serve as a dairy herd health consultant. My job is directly in response to cooperative members who are complaining of excessive abortions.
As I began my job, I first wanted to get an idea of the scope of the abortion problem and if one existed. The LaLa veterinarians have data to suggest that between 15 and 35% of the animals abort each year. Next I was presented with the graph on fetal age at abortion from one dairy. Most of the abortions appear to occur during the first trimester of pregnancy. I next asked about the vaccination program. The standard program followed was to vaccinate against Leptospirosis, Bovine Viral Diarrhea, Infectious Bovine Rhinotracheitis (IBR) and Brucellosis. As I could not work with all dairies in the cooperative, I selected 8 that were near the city and so easy for me to travel to each day.
From the dairies I was working with, I collected 50 fetuses from abortions over a 1-week interval and they were obtained from 6 of the 8 dairies. It was found that 17 fetuses had Brucella abortus infections as determined by isolation and compatible lesions, Neospora caninum was encountered in 13 fetuses, and Bovine Viral Diarrhea (BVD) virus was found in 1 fetus. Other diagnoses were: 10% infectious but unknown reasons, 10% infectious and presumptive bacteria and 7% had no lesions. There was no evidence of leptosirosis in any aborted fetus. Next we looked at the titers for the various organisms in cows that aborted and ones that did not (control). We found Neospora antibodies in serological tests in all herds but it was not well correlated with abortion. When testing for Brucella was done, we found several herds with >10% of the animals indicating an active Brucella infection. When looking for BVD, we found that when present in a herd, there was an association with abortion. There was no evidence of antibodies to IBR or Leptospspira beyond what would be expected from vaccinated animals.
I have to admit that I am a bit overwhelmed by the situation. This is a big responsibility for my first job, but if I succeed in making a difference, this could be a step to bigger opportunities.