Dave Thomas talks about OPP, ovine progressive pneumonia, its impact on U.S sheep flocks and what he is doing to eliminate the disease.
3:06 Total Time
0:12 – What is this sheep disease
0:37 – What are you doing to eliminate the disease
1:25 – What are the disease symptoms
1:55 – Are sheep breeders using your research with their flocks
2:15 – Are there other management practices to manage this disease
2:39 – How does the flock improve as the disease is eliminated
2:55 – Lead out
Sevie Kenyon: Eliminating a costly disease of sheep. We’re visiting today with David Thomas, Department of Animal Science University of Wisconsin-Madison, in the College of Agricultural and Life Sciences, and I’m Sevie Kenyon. David, tell us a little bit about this sheep disease you’ve been working on.
David Thomas: The disease is OPP, ovine progressive pneumonia, and it’s a disease that’s endemic in the U.S sheep population. It’s caused by a virus, and it results in less longevity in sheep and the ewes – the females- produce less milk. And so their lambs have reduced weaning weights.
Sevie Kenyon: And Dave you started working on this project, what are you doing to eliminate this disease.
David Thomas: Well we discovered that we had this disease in one of our two sheep flocks at UW-Madison. In December of 2011 we had about a 42 percent incidence of the disease in our flock. We started a program with our college veterinarians. We tested the whole flock, separated the positive ewes from the negative ewes. Lambed them at different times of the year, avoided fence line contact and we’ve tested them each year, the negative ewes and have eliminated the few positives that have returned. Until the last two years we have had 100 percent negative ewes, so we virtually eliminated it from the flock.
Sevie Kenyon: Tell us a little bit about the symptoms of the disease
David Thomas: Overtime the animal becomes emaciated, doesn’t respond to improved nutrition and eventually the animal dies. In between that they produce less milk, they have udders at lambing time that appear to be full of milk but there is very little milk there. Some of the ewes produce no milk at all. Which means that you have to raise the lambs then artificially. So it is a very serious disease for the U.S Sheep industry.
Sevie Kenyon: David, is your system being used by the sheep business?
David Thomas: Yes, there’s actually a group called Ovine Progressive Pneumonia Sheep Breeders Society. They have advocated the use of this technique in order to eliminate the disease from their flocks.
Sevie Kenyon: Are there other management practices that sheep producers can use to manage the disease?
David Thomas: Within the last year, The US Department of Agriculture has discovered a gene that results in reduced susceptibility, not resistance. If breeders would use rams that have this reduced susceptibility, they can increase the genetic tolerance of their sheep to this disease.
Sevie Kenyon: As the disease is removed from a flock what are the improvements?
David Thomas: More ewes producing a lamb each year that are negative for the disease. The lambs will have a greater milk supply and will grow faster. And you will have ewes living for a longer period of time in your flock.
Sevie Kenyon: We’ve been visiting with Dave Thomas, Department of Animal Science University of Wisconsin-Madison, in the College of Agricultural and Life Sciences, and I’m Sevie Kenyon.