Planning reduces disease risks
LOW SOW stress levels, a good setup and meticulous record keeping have contributed to minimising disease levels on a Norfolk outdoor pig breeding unit.
Management techniques have been devised to combat disease and improve performance, says farm manager Neville Dack, who runs a 2000-sow enterprise at Hillborough, Thetford, for MJ and JA Easey.
Out of the company’s 21 pig units, Hillborough is always second or third in the league table, sporting figures of 9-10% pre-weaning mortality, 2.4-plus litters a sow a year and 11.5-12.5 pigs born alive in each litter.
“Keeping performance up depends on records. We need to know what each sow has done, so every one is ear tagged and can be traced throughout the whole system. We have a full history of every animal from arrival until they leave.
“But the most important thing on an outdoor unit is the setup. Batch farrowing and single paddocks make a big difference to daily management,” stresses Mr Dack.
There are two 1000-sow units, staffed by a team of six, on 81ha (200 acres) of light land in rotation with vegetables on a shooting estate. “With six other pig units in the immediate area, we have to take the best precautions possible against disease,” says Mr Dack.
He believes it’s healthier and less stressful for pigs to be outdoors and says moving onto fresh land means there is no disease build-up. “However, we are beside a public road, so have no control over livestock vehicles passing by. And being open to the elements means we can have problems with birds – including crows – and foxes.
” While the estate’s gamekeepers take care of vermin control, disease control starts with good planning. The unit was set up to operate an all-in, all-out policy, restocking after six parities with gilts on another site. As part of a 14-year plan, pigs won’t return to the same site for at least four years.
This was done to combat pig wasting disease, as the company found it was more prevalent in litters from older animals, particularly when combined with other diseases.
So far, after three parities on the current site, culls haven’t been replaced by new gilts to maintain numbers. The effect of a closed herd has reduced the risk of brought-in disease, adds Mr Dack.
The unit layout is crucial for disease management and stress-free handling of stock. However, since sites must be restored to growing conditions, permanent fixtures are limited, so biosecurity starts with a semi-permanent disinfectant wheel wash at the entrance.
Pig net is erected along the boundary beside the road to maintain isolation and paddocks are electric fenced to keep pigs in and wildlife out.
Dry sow paddocks are in a radius around a central handling area with a separate hospital pen. This allows each group to be driven into the centre for vaccination before farrowing or pregnancy scanning.
Farrowing sows are managed in individual paddocks moving into clean, disinfected huts about 10 days before farrowing. This avoids non-mothering, and it allows stockmen to easily check piglets and monitor sow health and body condition, says Mr Dack.
“We walk in each paddock every day at feeding, so notice changes or problems straight away. The sows also get to trust us, reducing stress.”
Batch farrowing is another help. By concentrating on specific tasks, with staff specialised in key areas such as dry sow management, Mr Dack believes work is efficiently and effectively done.
“Each herd is split into seven batches of 140-150 sows. It means we have pigs born roughly every 26 days and we wean them all at once. This allows us to clean and disinfect huts, fenders and the soil where the hut was set.”
The nursery unit then receives 1500 weaners of the same age from one source, which reduces disease risk and pig stress levels. To reduce sow stress levels, trailers which can hold 12 animals only carry eight when moving stock between dry sow and farrowing paddocks.
Apart from removing tails at birth, to avoid tail-biting once pigs reach a finishing unit, piglets only have a single shot of pneumonia vaccine at weaning.
Gilts are vaccinated on arrival against Parvovirus, E coli and Erysipelas, with boosters before each farrowing. Catch boars are vaccinated against Parvovirus and Erysipelas.
“We worm twice a year using a feed additive and have never had mange, although that would only require a feed treatment.”