Pesti Virus at Shady Creek

Dianne Davey: PESTIVIRUS FARM NOTES 16/2/2022

Here follows in date order the farm events that led to the diagnosis of Pestivirus:

1. Heifer Gweny born 10/9/2017 at agistment property. She was very small.
2. 12/9/2017  Gweny weak, hollow and hungry. Her mother, a big Hereford had big teats. Into yards 2 days in a row to help her get a drink.
3. 24/11/17  Effie on heat with Bruno.
4. 1/1/2018  Effie not well – 20ml Duplocillin, 10ml Metacam, 10ml Vit C given. This is when Effie was infected with Pestivirus ( we didn’t know this at the time )
5. 20/7/2018 The 3 Big Girls with calves return from agistment. Calves are weaned.
6. 31/7/2018  Cool also pregnant to Bruno, has a very deformed calf, early and stillborn.
7. 3/8/2018   BVD test on deformed calf ear sample negative. Later was told by our Vet that it doesn’t necessarily mean it wasn’t affected by Pestivirus. Cannot remember reason why. It was complicated!
8. 5/9/2018 Effie steer born no problems. This was Effie’s first calf.
9. 22/11/ 2018 Gweny – significant weight loss noted.
10. 29/11/2018  Vet Stuart diagnosed Gweny as Persitently Infected (PI). Advice was to put her down. Need to test the herd for other PI’s using the ear notch test method. Started testing the 2017 and 2018 calves and Gweny’s mother.
11. 6/12/2018  Gweny put down! ☹
12. 24/12/2018 Effie very sore LHS back foot, treated, separated with steer and held in hayshed paddock.
13.  29/12/2018  Test results show Effie’s steer is PI
14. 31/12/2018 Checked Effie’s foot, ear notch taken, still separated with calf. Effie not a PI.
15. 17/1/2019 Effie and steer now with 2017 heifers and steers x 8. Not a problem as heifers are not pregnant and it is a way that they can safely get Pestivirus and develop their own immunity. They could have also been vaccinated for Pestivirus.
16. 14/5/2019 Weaning 2018 calves, Effie’s steer was retested to be sure to be sure. Effie and steer remained together with the 2018 calves. Effie did not get pregnant that year having been removed from the breeding herd since 24/12/2018.
17. 27/8/2019 Effie’s steer put down. He was in reasonable condition likely helped by still being with Effie. Vet Stuart advised to have him put down.

Since then we have had the calves each year tested using the ear notch test where you can borrow the ear notch tool from the Vet and they will supply small containers for the samples. You can do it yourself and you have a physical record as it takes a triangle of tissue from the edge of the ear which is easy to see for the rest of their lives. We have not had any Persistently Infected animals since.

Where did it come from?? We don’t know, however suspect it has come via neighbours, one side fattens a group of steers each year and the other agists dairy heifers. It is passed via transfer of body fluids eg touching noses.

We had a closed herd at the time so it was concluded it must have come over the boundary fence.

We now vaccinate all our bulls for Pestivirus.