The last time we discussed the clinical signs, diagnosis and control of coccidia in youngstock operations. This part will talk about the specific treatments and products available for treatment and prevention. It is important to work with your attending veterinarian to devise a plan for either case. Remember, if you are responding to only clinical cases, you are missing 95% of affected animals in need of cocci control.
Coccidial products are divided by their mode of action, coccidiostatic or coccidiocidal. Static ones do not kill, but only slow, weaken or arrest the life cycle of coccidia. Cidal ones have the ability to outright kill. It is important to note that neither mode of action assures that all organisms are affected at all stages of the life cycle. This means that it is impossible to totally eliminate all coccidia within the intestinal tract. Total elimination is not necessary, nor desired. Exposure is required for resistance to be achieved.
Products are further classified based on strategy of use. They can be preventative or therapeutic.
What are the products available for coccidia control?

SULFONAMIDES (SULFAS)
• Sulfas have been used for many years as a therapeutic agent. They have a static effect on coccidia. Resistance is reported to be fairly common, however.
• Sulfas reduce the formation of folic acid (a B vitamin) by the coccidia, a necessary micronutrient for growth. Coccidia thus experience a serious reduction in growth and possible death. Animal cells use preformed folic acid present in the diet and are not affected adversely by sulfas.
• Aureo-S Crumbles?(sulfamethazine and Aureomycin) are widely used to prevent or control respiratory infections, but have been effective at controlling low to moderate challenges from coccidia. The high level of intake required and the loss of appetite in cases of severe coccidiosis make Aureo-S use impractical in these situations.
• Albon?(sulfadimethoxine) boluses and powder have been effectively used in severe cases when directly administered orally to clinical animals.
• The simultaneous use of Corid?(amprolium) and sulfas appears to be very effective in serious cases, although not FDA approved.

AMPROLIUM (CORID? )
• Amprolium is a cidal product used both as a preventative and therapeutic. Corid? is the most commonly used brand. It is available in liquid, soluble powder and crumbles. The product is never included in manufactured products.
• Amprolium is an antagonist to thiamine (vitamin B-1). Thiamine is required by coccidia for growth and development at a rate 10 times that of animal cells. Without sufficient levels, coccidia die. The safety factor for mammals is 8 times therapeutic levels.
• Amprolium resistance is reportedly high; however, effectiveness of the product reported from the field appears to be unchanged over the years.
• Liquid amprolium can be used safely in young calves by adding it directly to milk or milk replacer once a day.
• Amprolium may be used for 5 days in a row at treatment levels (twice the preventative rate) as early as two weeks of age and repeated in 15-20 days in high early exposure situations. It can be fed in the crumbles from near weaning at treatment levels for 5 days before stress related coccidiosis breaks are expected. This may be in addition to ionophores and Deccox? present in the grain.
• Amprolium crumbles are effective in treating breaks in older calves that are still eating fairly well. A more prolonged treatment regime at therapeutic levels may be advised. Simultaneous administration of sulfas has proven beneficial, although it is not FDA approved.

QUINOLONES (DECCOX?)
• Deccox? (decoquinate) is a static compound used as a preventative. It has only one point of interaction within the life cycle of coccidia. It is absorbed into the cells lining the gut where the reproductive phases of coccidia take place.
• Deccox? disrupts the energy transport system of coccidia reducing the growth and reproduction, but not killing the organism. The advertised rationale has been to allow the immune system to “see” the organism whole, alive and in significant numbers while rendering it harmless. Resistance has been reported.

• It is extremely important that effective control levels are maintained on a daily basis. A short-term absence of Deccox? in the feed allows the “arrested” coccidia to rupture out of the host cells. Explosive episodes of clinical coccidiosis can result depending on the level of previous exposure to infective oocysts. This is a common scenario when switching from Deccox? to one of the ionophores, particularly around weaning.

• Fecal examinations performed in the early stages of these Deccox? “breaks” will be negative.

• Decoquinate can be manufactured with milk replacers and starter grains. In the form of a powder, Deccox-M? can be hand mixed with milk replacer or whole milk.

IONOPHORES (BOVATEC? & RUMENSIN?)

• Ionophores are cidal compounds generally used in prevention. They have three points of control on coccidia during its life cycle, all during the extracellular phase or when the organism is released into the rumen of the gut.

• Ionophores disturb the electrolyte vs. water balance within the coccidia causing them to swell and burst. Resistance is possible, but unusual.

• On a milligram per milligram basis, Rumensin? (monensin) is about 30 to 50% more potent than Bovatec?(lasalocid) for coccidial control.

• Ionophores are particularly toxic to horses and other equidae. Rumensin? is more toxic than Bovatec? in these species.

• Bovatec? is approved for inclusion in milk replacers. Rumensin?is not. Both can be routinely used in starter, transition and grower feeds as growth promoters as well as a coccidial control agent. They should be continuously fed at least until coccidial control is deemed unnecessary.

• Crossing over from one to the other does not appear to cause any break in control or create any adverse reactions. Lapses of a few days in treatment (either suboptimal or complete) do not result in explosive clinical disease. Overlapping may create excessive total ionophore levels leading to decrease feed intake. Ionophore toxicity has been reported in young pre-weaned calves where inclusion rates have accidentally exceeded safe limits.

• Ionophores are almost exclusively blended at manufacture in retail feed products. This is the most economical means of inclusion. One exception is a product containing Bovatec?, vitamins and minerals called CalfPro?. It is a liquid designed to add to milk or milk replacer for the first three to four weeks of a calf’s life until medicated starter intake is sufficient for coccidial control. It is available in liters and gallons.