Experience with clearing herds for BVDV infections Practitioner Jørgen Katholm Vivild Denmark

Herds with PI

Herds with PI

Herds with PI

Herds with PI

Herds with PI

Herds with PI

Herds with PI (2 beef herds)

Herd symptoms months from birth of PI calv Recycling Diarrea, cows, reduced milk Dead cows reduced immunity, severe coliform mastitis, ringworm, pyogenes infections. High Bulk milk cell count Abortion storm week calves born, calf diarrea, (Seropositive calves) Growth retarded calves malformated calves, blind Stillbirth 0 - 2PI calves Retaind placenta 0 - 3Week calves, diarrea 1 - 4Lunginfections 2 - ?Sudden death of PI calves Mucosal Disease

BVD Eradication Individual marking:Ear tags (database) Trade restrictionsBiosecurity (status of BVD) Blood testingRelaibel tests PRICE Education of vets.Brownlie, Alenius, Kalis Practising Vets Education of farmersVets from farmer organisations Local vets Trend setting FarmersFree of infection Infected - Time scale of disease

All Herds infected and clean 1994 Trend setters Free 5-10 years

First eradication

BVD Eradication plan 1990Test all cattle for antibodies (PRICE – Holland 1/3) Test all negative for virus by virusculture Herd status antibody in 5 bloodsamples 1994 Test all cattle > 3 month for virus (ELISA) Until 1 year after last PI no antibod testing (PRICE) Farmers organisation started volontary BVD-Status Milk: 4 times/yearBeef 3 blood for antibodies/year Infection stops to spread BUT 3 farms bought seropositive heifers calving with PI

All Herds infected and clean 1994

Beef Herds Infected 1996

Beef Herds in Vivild Total infected 10herds 8 with PI

Beef Herds Infected 1999

Last PI Beef herd killed 8 dec 1999

Milking Herds infected and clean 1994

Milking Herds Infected 1995

Milking Herds in Vivild total 54 infected 40 with PI

Milking Herds Infected 1999

Milking Herds Infected 2000

Last PI killed 16 jan 2001

All Herds 2003 Free

Normal calves negative 8 month 1 HF calv positive 10 months negativ 14 months 1 beef calv positive12 months negativ 13 months Maternel antibodies

BVD antibodies in Charolais young stock

BVD antibodies in Charolais young stock 22/ calves dehorned + 1 BVD antibodies negativ

BVD antibodies in Charolais young stock 5/ BVD blodsamples for status positive positive positive

BVD antibodies in Charolais young stock 18/ BVD blodsamples positive positive positive positiv negative

BVD antibodies in Charolais young stock 27/ BVD blodsamples all herd 939 negative 930 negative 938 negative 925 negative 937 negative 931 negative 920 negative 915 negative 934 negative 919 negative 929 negative 916 negative 911 negative 926 negative 921 negative 923 positive 912 negative 933 positive 935 negative 922 positive 913 negative 924 negative 936 negative 917 positiv 910 negative 927 negative 918 positiv negative 940 negative 928 negative 914 negative

Conclusions Happy farmers will spread the news Biosecurity - stops the infection Eradication - straight forwad When going for the virus and the tests are reliable Big herds maybe prolonged eradication seperated flocks selling of young calves No spread from Bull stations by semen Injections with infected medicine can cause acute infection

Thank you For BVD eradication