National Pig Association THE VOICE OF THE UK PIG INDUSTRY NPA is active on members' behalf in Brussels & Whitehall, and with processors, supermarkets & caterers – fighting for the growth and pros-perity of the UK pig industry.

Respiratory disease in pigs is usually preceded by some form of stress, which suppresses the immune system and allows an initial pathogen to set up an infection or a secondary infection to complicate an existing sub-clinical problem.

Changes in the physical environment, such as air temperature, humidity or ammonia levels, or stress caused by handling or transportation are common factors.

High stocking levels, continuous flow production and other management practices that promote pig-to-pig contact and mixing of pigs of different ages, contribute to the risk of an outbreak. Poor ventilation of buildings also predisposes to respiratory problems. However, infections may also occur in the absence of any obvious triggers.

The first line of defence against respiratory infection is prevention. Providing an optimal environment, with good ventilation, correct stocking density, age-matched groups and all-in all-outmanagement will help to reduce the risk, as will good biosecurity procedures.

Vaccines are available for many of the common pathogens either singly or in combination and are the only viable form of protection against viral infection. The prophylactic use of antibiotics in feed or water for the prevention of bacterial infection is no longer supported by EU legislation on the basis that this does not comply with the prudent use of such drugs.

In-feed and in-water antimicrobials may still be used to treat infected animals and injectable products are also available for the treatment of respiratory disease.

With tulathromycin therapeutic levels of active drug are maintained in the lungs for at least nine days in cattle and five days in pigs. Pfizer say this makes it the longest acting single-dose full course therapy available to European vets and producers.

"In the past, the best we could hope for was three or four days' cover from a long-acting antibiotic. Draxxin has more than doubled this," said Nigel Evans, group director of veterinary and professional services for Pfizer Animal Health.

Source: National Pig Association Digby Scott - 11th February 2004