Guard Against Old Bacterial Diseases

Seldom seen today, these diseases can quickly change health in finishing groups.

With today’s challenge of high feed costs and ever-tighter margins, herd health has become invaluable. When a disease shows up unexpectedly, it can very quickly turn a projected profit into a substantial loss. Although not commonly seen, Actinobacillus pleuropneumonia (APP) and Actinobacillus suis (A. suis) are both bacteria that can show up in a group of finishing pigs and quickly change the outcome of the group.

Case Study No. 1

This feeder pig finisher has two, 2,000-head finishing barns on separate sites. He purchased pigs on a contract for three years, until the source farm decided to discontinue selling feeder pigs. To keep his barns full, he purchased pigs on the open market. With smart purchasing and marketing decisions, he locked in a $15 profit per pig.

We did a “vet-to-vet” consultation to check on the health of the pigs. There were no known problems, and the health appeared slightly above average. The pigs started well, but it took four weeks to fill the sites. Two months later, pig activity decreased and water consumption dropped 20%. Some diagnostics indicated pigs were seroconverting for porcine reproductive and respiratory syndrome (PRRS). We treated pigs conservatively with aspirin in the water and treated individual pigs with injectable penicillin. Death loss was minimal for the first seven days, but started to increase to 1-2/day the following week.

We visited the farm again and conducted postmortems, which indicated a severe bacterial pneumonia. Diagnostics confirmed APP. We put tilimicosin in the feed for three weeks and treated individual pigs with injectable enrofloxacin. The group finished with a cough throughout the remainder of the feeding period and, while death loss was reduced, at 6% it was twice the level the producer used in his projection.

But more costly was the poorer than expected feed efficiency. The group finished at 2.90 when they were projected to be at 2.75, and the group’s profit was $1.25/pig instead of the projected $15.

Case Study No. 2

This 2,800-sow, farrow-to-finish farm finishes pigs in contract wean-to-finish barns. The pig flow is 1,200 pigs/week, and it takes two weeks to fill each 2,400-head barn. Wean-to-finish death loss averages 5%.

Approximately six months ago, we noted an increase in death loss two weeks after placement. From each delivery of pigs, 5-10 pigs that appeared in good health would suddenly die.

The postmortems we completed showed a severe, consolidating pneumonia, which was identified in the laboratory as A. suis. We felt this was elevating death loss by 0.5-0.8%.

To lower the death loss, we treated piglets with injectable ceftiofur at processing, and to date it looks like we may have reduced or eliminated the problem. We want to continue the treatment for a full year to be sure we can attribute the improvement to the antibiotic injection.


APP and A. suis are bacterial challenges that have plagued pork producers for years. We are seeing fewer problems with these bacteria as genetic companies have recognized the importance of disease in profitability for their customers and their role in improving it.
These companies have diligently worked at cleaning up disease in their multiplier farms, and this has translated into improved health on their customers’ farms, especially for APP. This disease has gone from being diagnosed almost weekly to an infrequent occurrence. Genetic companies have made it a priority to eliminate APP from their herds, and it has paid dividends to their customers.

A. suis still shows up occasionally and can become a problem in certain flows. It is not as severe and costly to the pig farms as a whole and has not been as important to eliminate from herds. In some flows, however, we have found it necessary to vaccinate. The use of antibiotics or vaccines or a combination of the two will usually provide good control.

APP and A. suis can look the same clinically and on postmortem exams. It is necessary to culture the bacteria to get an accurate diagnosis. This is important to do, as long-term control of these two bacterial pathogens requires different strategies.

If you feel that death loss is higher and performance is poorer than you would like, ask your local veterinarian to pursue an accurate diagnosis and assist in designing a treatment and control strategy that works best for your farm. Health is king and should be a priority on all farms, both small and large.