Case Study 5 Nella Bernardoni Otto Kraus Mindy Wesely

Case  Discovered an aborted fetus from a mare in her 9 th month of pregnancy  Vet requests an abortion necropsy, as well as tissue sampling to be sent to lab.  What is the likely cause of the abortion?

Timeline

What happened?  The symptoms (runny nose, cough) along with normal appearance prior to abortion indicate that the mare developed Rhinopneumonitis. Caused by Equine Herpes Virus Type 1 (EHV-1) Caused by Equine Herpes Virus Type 1 (EHV-1) Two subtypes produce different symptoms: Two subtypes produce different symptoms: Sub-type 1: Causes abortions, respiratory, and neurological diseaseSub-type 1: Causes abortions, respiratory, and neurological disease Sub-type 2: Respiratory strainSub-type 2: Respiratory strain

Vaccination Schedules DiseaseAdministrationComments Tetanus Toxoid One month before foaling. Local tissue reaction; anaphylaxis (shock) in some horses. Botulism Initially, at leasst 3 times during gestation, 1 month apart with the last injection 2-4 weeks before foaling. Annual vaccination 2-4 weeks before foaling. Local tissue reaction; anaphylaxis (shock) in some animals. Heat and minor swelling may occur at the injection site. Rabies Annually, before the breeding season. Local tissue reaction may result if injected subcutaneously. Influenza Annually in low risk areas; some also recommend the last month of pregnancy. Do not vaccinate 2-3 weeks before a stressful event. Some horses have a brief fever, loss of appetite, and depression after vaccination. Check with veterinarian for guidance. Rhinopneumonitis Pregnant mares at 5, 7, and 9 months of gestation. Open and maiden mares at the same time as pregnant mares. If mares are beyond 5 months of pregnancy at first vaccination, continue with vaccination every 2 months until birth. Deep intramuscular injection in hind leg. Mild exercise to promote absorption is recommended for one week after injection. Equine Viral Arteritis Open or maiden mares but at least 3 weeks before breeding. DO NOT VACCINATE PREGNANT MARES. Horses may have a mild fever and decrease in white blood cells after vaccination. Burn container and any unused vaccine. Not a routine vaccination. *Table adapted from Animart Copyright ©

Vaccination Schedules A proper vaccination schedule might have prevented the abortion.

Necropsy and Tissue Sampling  Tissues collected Lung, trachea, bronchial lymph node Lung, trachea, bronchial lymph node Endothelial cells of the placenta and uterus Endothelial cells of the placenta and uterus  Possible tests Isolation of EHV-1 from tissue listed above Isolation of EHV-1 from tissue listed above Anti-body assay from horse serum Anti-body assay from horse serum

Fixing the Problem  Mare in 6 th month of pregnancy has not received EHV vaccination. Vaccinate in the 6 th, 8 th, and 10 th months to get back on vaccination schedule Vaccinate in the 6 th, 8 th, and 10 th months to get back on vaccination schedule

Vaccination Schedules DiseaseAdministrationComments Tetanus Toxoid One month before foaling. Local tissue reaction; anaphylaxis (shock) in some horses. Botulism Initially, at leasst 3 times during gestation, 1 month apart with the last injection 2-4 weeks before foaling. Annual vaccination 2-4 weeks before foaling. Local tissue reaction; anaphylaxis (shock) in some animals. Heat and minor swelling may occur at the injection site. Rabies Annually, before the breeding season. Local tissue reaction may result if injected subcutaneously. Influenza Annually in low risk areas; some also recommend the last month of pregnancy. Do not vaccinate 2-3 weeks before a stressful event. Some horses have a brief fever, loss of appetite, and depression after vaccination. Check with veterinarian for guidance. Rhinopneumonitis Pregnant mares at 5, 7, and 9 months of gestation. Open and maiden mares at the same time as pregnant mares. If mares are beyond 5 months of pregnancy at first vaccination, continue with vaccination every 2 months until birth. Deep intramuscular injection in hind leg. Mild exercise to promote absorption is recommended for one week after injection. Equine Viral Arteritis Open or maiden mares but at least 3 weeks before breeding. DO NOT VACCINATE PREGNANT MARES. Horses may have a mild fever and decrease in white blood cells after vaccination. Burn container and any unused vaccine. Not a routine vaccination. *Table adapted from Animart Copyright ©

References Stone, J. (2001, October 29). Caring for Your Pregnant Mare. In College of Veterinary Medicine: Office of Public Engagement. Retrieved November 27, 2006, from University of Illinois Web site: Equine Herpesvirus Type I. ( ). Equine Assay Data Sheet. Retrieved November 27, 2006, from Zoologix, Inc. Web site: Necropsy Kit. (2006). Retrieved November 27, 2006, from Montana's State Website Web site: Equine Rhinopneumonitis (Snots). (n.d.). Pet Care Tips: All About Equine Rhinopnuemonitis. Retrieved November 27, 2006, from Equine Vaccination Schedule. (2006). Animart. Retrieved November 27, 2006, from

That’s all, folks!