15 February 2021
Paul and Samantha Barcroft-Jones embarked on a screening programme after sudden deaths in several growers and finishers.
Actinobacillus pleuropneumonia (APP), a highly contagious respiratory disease that affects 6-18-week-old pigs, was identified.
Key clinical signs include breathing difficulties, blueing of the ears and, in severe case, sudden death with haemorrhaging from the nose.
In response to the test results, pigs were vaccinated at six weeks and nine weeks old but pigs reacted adversely to the vaccine and the death rate in the grower pigs increased by 5%.
Penicillin was added to the feed ration, bumping up feeding costs by £2/pig but this resolved the APP issue.
The Barcroft-Jones’, who run their Large White x Landrace herd in a fully-slatted temperature controlled building at Llwyn yr Arth, near Llanbabo, Anglesey, now have a regular screening programme in place.
They say this is essential because the mortalities alone resulted in weekly income falling by 8% for six weeks.
Another challenge the unit has faced was tail biting after zinc oxide was removed from the pig diet as a trial ahead of the proposed UK ban in June 2022.
Within six weeks of the mineral being excluded from the ration, cases of tail biting and chewing increased significantly, says Mr Barcroft-Jones.
“The pigs were scouring and tail biting was the secondary problem, 30% of pigs per batch were affected with tail biting,’’ he says.
Days to slaughter in these pigs increased by seven days and average slaughter weight reduced by 5kg, to 75kg deadweight.
This resulted in extra feed costs equivalent to £3.50/pig/week and lost income of £8/pig from lower slaughter weight.
As pigs were on the farm for longer, variable costs including electricity and water were higher.
A Farming Connect focus site project was established to investigate ways to reduce vices at the pig unit and to improve understanding of herd health.
Health screening established that a cause of the change in pig behaviour was Brachyspira pilosicoli, a disease which results in the large intestine becoming distended and mucosal thickening occurring, hampering the effectiveness of the enzootic pneumonia vaccine.
In response to that diagnosis, zinc was re-introduced as a treatment in the first stage grower ration, for pigs up to 18kg.
Antibiotics were added to drinking water for five days as a treatment for enzootic pneumonia EP.
“This was very costly but worked well as a treatment for the pneumonia,’’ says Dafydd Owen, Farming Connect Pig Technical Officer, who managed the project at Llwyn yr Arth.
Piglets were vaccinated for pneumonia earlier, at seven days instead of 14, to enable immunity at an earlier age.
Mr Owen says the project had highlighted how important it is to have a good understanding of a herd’s health status. Regular testing is key, he suggests.
“Carrying out a herd health assessment allows pig keepers to fully understand the health status of the herd and allow sensible management decisions to be made,’’ says Mr Owen.
“The change in vaccine and the re-introduction of zinc caused a significant reduction in biting and antibiotics were used to treat vice-related injuries and sickness.’’
However, these changes are short-term answers to the problem, he adds.
The project demonstrates that further research is needed to find a supplement to replace zinc oxide, says Mr Owen.
Antibiotic usage in the herd at Llwyn yr Arth during the third quarter of 2020 was 1.298mg/kg compared to the 63.074mg/kg sector average.
The Barcroft-Jones’ have used the health assessment of their herd to set management protocols to control and prevent vices from becoming a problem in the future.
They are focussing on cleanliness at all stages of pig production in a bid to lower infection rates and antibiotic usage.
Pig system at Llwyn yr Arth
Feed conversion efficiency is an important key performance indicator for the business.
Four feed rations are used to achieve the target of producing 1kg of liveweight from 2kg of feed.
The pig housing, which replaced a system of old farm sheds in 2014, has automated feed systems and capacity to store five-months’ worth of slurry.
“The old sheds were far from ideal because they were cold for the pigs in the winter and hot in the summer,’’ says Mr Barcroft-Jones, the second generation of his family to farm 200-acre holding.
All breeding is done through artificial insemination – around 28 sows are served every three weeks to a MaxiMus or Piétrain.
Good fertility is one of the performance indicators that dictates if a pig stays in the herd - the target conception rate is 95%.
The Barcroft-Jones’ have a replacement rate of 45% or higher, culling for rearing ability, mastitis, fertility and health issues.
They like to keep the herd young – sows produce an average of 2.4 litters a year, 25-26 pigs born alive, and they remain in the herd for an average of four litters. Those that achieve six litters leave the herd at that point.
The sows are fully housed on straw and farrow in a 60-crate unit on a three-week farrowing system.
Tail, ear and flank biting or navel sucking behaviour can be serious in groups of growing pigs, particularly when it results in secondary bacterial infections.
Vices in both weaned and growing pigs can be a major problem on some farms with considerable economic loss.
If there is a problem on the farm, consider the three major contributing factors; management, nutrition and disease.