Coccidia are still alive and well. These persistent protozoan parasites continue to do damage in today's pork production systems.

Pork producers are still battling the microscopic menace known as coccidia - without benefit of an approved anticoccidial agent or vaccine.

Isospora suis is the most common coccidia causing problems in baby pigs. The Eimeria genus is the more common cause of coccidiosis in older and adult swine.

Coccidiosis is strictly a warm-weather parasite problem. Warm temperatures are needed for the coccidia egg or oocyst to form spores.

Four to five days after infection, baby pigs can shed up to 400,000 oocysts/gram of feces. The organism can remain viable in the soil at a wide range of temperatures for up to 15 months.

Since the sow is not the primary source of coccidia organisms for baby pigs, sow treatment is not effective for reducing baby pig coccidiosis.

Two cases are reported; one describes a very common manifestation of coccidiosis and one quite an unusual presentation of the parasite.

Case Study No. 1 A group of 6-month-old replacement gilts was delivered to an isolation lot last fall. This was a dry, dirt lot with a self-feeder. Gilts were reared in totally slotted floor finishers. Feed medication on arrival was 100 g/ton of tylosin to control ileitis.

Ten days after arrival, three gilts died. At postmortem, these gilts had severe damage to the lining of the small intestine.

Several other gilts were thin, exhibiting watery diarrhea and inactivity. Elevated rectal temperatures were seen in some gilts, one at 106ΓΈ F.

Samples sent to the diagnostic lab revealed numerous stages of coccidia in the jejunum (mid-small intestine). Other tissues showed no signs of salmonellosis or ileitis.

Death of some replacement gilts may have been due to toxemia when the lining of the intestine was disrupted by the severe parasite infestation. The rest of the replacement gilts recovered and problems have not reoccurred.

Coccidiosis was probably caused by naive gilts being exposed to numerous organisms. Coccidia are more likely to accumulate on dirt lots or solid floors. For isolation and acclimation, many gilts are housed in off-site facilities that often provide greater opportunity for exposure to parasites.

Case Study No. 2 A 900-sow farm experienced increased baby pig diarrhea that was malabsorptive (milk not fully digested), watery to creamy in consistency and acidic in pH. Pigs didn't respond to antibiotic treatments. Samples were submitted to the diagnostic lab. Only low numbers of E. coli were isolated.

However, a large number of various stages of the life cycle of coccidia were observed in microscopic sections of the small intestine and the diagnosis was coccidiosis.

In a review of sanitation procedures, the decision was made to switch to strong bleach (50% household bleach) solution. Strong ammonia solutions can also be used. Care must be taken with these compounds. Do not mix them.

The affected farm has several different farrowing houses with different types of floors. The rooms with plastic perforated floors experience the most cases of coccidiosis. These floors don't stay as dry as woven wire, round bar or Tri-Bar style floors. This may be the reason diarrhea is more prevalent in these rooms.

With more emphasis on sanitation, different disinfectants and using an extra-label coccidiastat in an oral, iron-based solution, the scouring problem has been reduced.

Mortality rates have been reduced from 15% at the onset of problems to less than 12%.

The two wean-to-finish barns for this farm have concrete slat flooring. We were concerned this might cause recurring problems with coccidia postweaning.

However, other than higher death loss in the groups affected in the farrowing rooms, this has not developed into a postweaning problem. The literature of problems includes some reports with postweaning coccidiosis.

Summary As previously mentioned, there are no approved coccidiastats in the U.S. for pigs. Extra-label drug use may be considered upon the recommendation of your veterinarian.

But, it is difficult to get adequate amounts in baby pigs and at the right time. Controlled studies with presently available products for other species have not produced rewarding results when used in pigs.

Our Canadian friends do have an anticoccidia product that is reported to be effective, so there is hope that someone will develop a product for the U.S.

Farms with a history of problems should consider using the more effective disinfectants against coccidia during the summer months.