Abstract: Immunovaccination while feeding

Type and Average of Pigs on the Farm

The farm maintains approximately 22,000 grower-finishers.

Farming System

Intensive production system.

Description and Evaluation of the Good Practice

This good practice describes a simple method to vaccinate male pigs with an immunocastration vaccine while they eat. Pigs receive liquid feed via long troughs four times daily, every six hours. The two feedings prior to vaccination, pigs are given 50% of their normal ration; during the vaccination feeding they receive 150% to ensure all pigs come to the trough. Each feeding cycle lasts 150 seconds — sufficient to vaccinate all 32 pigs sharing the same valve. After vaccination, each pig is marked with colour spray on the back. Pigs are sorted by sex, with males on one side and females on the other, all receiving the same diet with a final feeding level of 3.5 feed units per day. The practice also works on farms with ad libitum dry feeding, where the farmer simply walks slowly among the pigs in the pen.

Farm Context

• Pigs Grower-finisher only herd. Final weight: 115–122 kg live weight; slaughter age: 18–22 weeks. The farmer produces meat for premium markets, which provides an additional payment per kilogram for pigs with a high lean meat percentage.
• Housing and Management Characteristics Floor type: combination of slatted and drained flooring. Feeding: liquid feed with own supply of grain and a high level of rye; 2-phase feeding from 30–60 kg and from 60–120 kg; four times per day.
• Management Practices Immunocastration with 2 injections. First injection 2–3 weeks after insertion when pigs weigh around 45 kg; second injection four weeks thereafter. All injections scheduled on the same day each week. Ages at injection: 13–14 and 17–18 weeks. Vaccination via safety injector; slow and calm procedure; pigs eat during vaccination and hardly notice the injection. Boar taint: proportion of carcasses rejected below 1%. Implemented by farmer and employees; 1 person per batch.

Economic Analysis

Average productivity for both female and immunovaccinated male pigs: daily gain 1,134 g; FCR 2.20 FU/kg; meat percentage 60.7%; carcass weight 91.4 kg. Immunocastration costs approximately 25 DKK per pig covering both vaccinations and labour. The proportion of carcasses rejected due to boar taint has been reduced from 3% to 1%.

Environmental Analysis

This practice has no direct environmental impact. However, the better feed efficiency of immunovaccinated males results in a lower environmental impact compared to surgically castrated pigs. Climate savings from immunovaccinated males versus barrows are estimated at approximately 8.7 kg CO₂e per pig.

Replicable Benefits and Relevance for Other EU Countries

This good practice shows how easy it is to vaccinate finishing pigs with an immunocastration vaccine, especially when pigs are fed liquid feed. It can be implemented by pig farms of various herd sizes.