1. An Outbreak of Viral Respiratory Disease in an Ontario Dairy Herd Jenna Donaldson OVC 2013 http://www.sciencedaily.com/releases/2010/06/100607065902.htm

2. Case History Signalment Holstein herd milking 53 cows Presenting Complaint Whole herd off feed

3. Herd Management Barn design Nutrition Total mixed ration Vaccine protocol MLV Biosecurity No showing animals, heifers raised on farm Schematic of Barn Layout

4. Background Above-average maximum daily temperature and relative humidity prior to initial farm visit Initial farm visit http://climate.weatheroffice.gc.ca/climateData/generate_chart_e.html?timeframe=2&Pr ov=ONT&StationID=48569&dlyRange=2010-04-18|2012-11- 13&Year=2012&Month=6&type=line&MeasTypeID=maxtemp&Day=13 http://kitchenerwaterloo.weatherstats.ca/charts/relative_humidity-1year.html June 2012

5. Initial Investigation Water No changes Feed New 1 st cut haylage fed for 4 days Gradual decrease in feed intake over 3 days Mold contamination of high-moisture corn http://www.kosvi.com/courses/vpat5215_1/vpat5310/

6. Herd Exam Milking cows slightly dull Mild tachypnea w/ normal respiratory effort Increased mucoid nasal discharge 40% of herd scouring Many cows pyrexic Rumen motility normal to decreased Not interested in TMR No mucosal lesions noted

7. Viral Respiratory Disease Differentials Bovine coronavirus Parainfluenza-3 Infectious bovine rhinotracheitis Bovine respiratory syncytial virus Bovine viral diarrhea

8. Bovine Coronavirus Pneumoenteric virus Fecal-oral and aerosol transmission Subclinical infection 3 common clinical syndromes Respiratory disease typically mild

9. Initial Management Vaccinated all animals with intranasal IBR/BRSV/PI-3 modified-live vaccine Milking Cow Management Rectal Temperature (°C) # of CowsTreatment Administered <39.5°C19Vaccine only 39.5-39.9°C11Vaccine, ketoprofen IM once >40.0°C23Vaccine, ketoprofen IM once, ceftiofur IM for 3 days 53 cows total

10. Lab Diagnostics for Respiratory Disease Polymerase chain reaction (PCR) and/or virus isolation Nasal swabs from live animals Fecal samples (useful for bovine coronavirus) Postmortem: URT tissue, lung, lymph nodes, liver Virus neutralization (serum) Histology on postmortem tissues

11. Laboratory Diagnostics Bovine coronavirus titres Acute and convalescent samples (14 days apart) Virus neutralization at AHL Four cows tested No clear demonstration of seroconversion Bovine Coronavirus Titres Cow #AcuteConvalescent 11:512 2 3 1:1024 41:5121:1024

12. Prevention and Management Nutrition and silo management Ventilation and barn design Vaccination program Biosecurity

13. Herd Outcome Milk production returned to normal in ~14 days One abortion at 60 days gestation Initial farm visit

14. Cost to Producer Veterinary costs: ~$1600 Professional time and products (intranasal vaccine, anti- inflammatory, antimicrobials) Estimated lost milk: ~$4100 Laboratory diagnostics Coronavirus titres x 4 cows: $150 Full respiratory serology panel: $120 /cow

15. Acknowledgements Dr. Ray Reynen Heartland Veterinary Services Dr. Jessica Gordon http://rocksolidnutrition.wordpress.com/category/dairy/