1. Case 6: Neosporosis Linda Behling Sarah Galdi Jamie Jergenson

2. Case Summary Herd manager for a 3,000 cow dairy located in Southern California Abortions in 20% of first lactation heifers during first 4-6 months of pregnancy and cows aborting at 5 months Blood test is being run, but results not back yet Suspected cause of abortions is Neosporosis

3. Cause and Transmission Caused by protozoan Neospora Caninum Transmitted two ways –From cow to calf (across placenta) –From host to cow (ingestion of contaminated feed)

4. Transmission

5. Results of Neospora 3 possibilities for fetus: –1.) Fetus becomes infected early and is aborted –2.) Fetus is infected late, pregnancy maintained but calf is born with neurological diseases –3.) Fetus is infected late, pregnancy is maintained, calf is born normally but is more likely to abort during first gestation than heifers not infected

6. Economic Impact on Dairy Herd Cows with Neospora have: –Decreased milk yield –Decreased reproductive efficiency –Decreased weight gain and feed efficiency –Decreased value as breeding stock In California, the approximate economic loss from both abortion and other factors (semen, breeding, vet costs, open/not milking) is $35,000,000/yr

7. Treatment No effective drug or vaccine available Suggestions to reduce incidence: –Remove all cows infected with Neospora –Test replacement heifers and newborn calves –Reduce stressors (low quality feed stuffs, overcrowding and excessive heat) –Prevent horizontal transmission by preventing fecal contamination of cattle feed

8. Diagnosis ELISA test Blood samples

9. Likely Situation at CA Dairy Wildlife infected with Neospora by consuming an infected aborted fetus Wildlife are contaminating feed supply First lactation heifers and cows (that are housed together) are ingesting the feed Cattle are passing disease on to fetus (some of which survive and carry the disease to their offspring)

10. Should the herdsman be fired? No, Neospora is not tied directly to his or her herd management responsibilities –He just began this past year and the initial infection would have started with the later lactation cows before he was hired. Improved pest control methods must be implemented to control the presence of wildlife around the dry lot Coyote/Dog Fencing Live Traps

11. Sources Washington State University College of Veterinary Medicine http://www.vetmed.wsu.edu/depts_waddl/Neosporosis.asp United States Department of Agriculture Agricultural Research Service http://www.ars.usda.gov/Main/docs.htm?docid=11007 The Merck Veterinary Manual http://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/51600.h tm