Volume 16, No. 11
Cryptosporidiosis is a parasitic disease that compromises the immune system and allows many other diseases to get a foot hold. Pasteurella multocida is the best example. It is a normal inhabitant of the upper respiratory system of the calf. The Crypto suppresses the immune system and allows the Pasteurella organisms to multiply and produce pneumonia. If Crypto is controlled many other diseases do not get a chance to cause trouble.
The cow is the carrier and the calf picks up the organism from the manure on the cow’s teats, or from the calving area as well as from the calf housing. The calf swallows the Crypto organism and it burrows into the wall of the gut just below the cell membrane, but outside the cytoplasm of the intestinal cells. It remains their incubating for approximately 48 hours and then emerges into the lumen of the gut. About half of the oocycsts pass out with the feces and contaminate the environment, and the other half turn around and dive back into the lining of the gut and start incubating again. Just one Crypto organism on day one, which cycles every 48 hours, becomes one million by day eight. I treat Crypto with 50 mg of decoquinate activity per calf per feeding for the first 10 to 14 days of the calf’s life. Decoquinate is a contact killer and must touch the Crypto organism to kill it. So while it is buried in the wall of the gut, the decoquinate will not kill it. The decoquinate must be in the lumen of the gut at the time the Crypto pops out of the wall of the gut, to kill it. That is why it is extremely important to feed at least twice a day. The treatment is not 100% as there are times the Crypto can emerge from the wall of the gut and there is no decoquinate in the lumen. Decoquinate is only soluble in chloroform and not in milk or water. So it is important to place the correct dose in each individual bottle, bucket or calf’s mouth. It cannot be bulk mixed except in tanks that have recirculating pumps, as most veal raisers do.
There are three strengths of decoquinate sold. Deccox-M is 0.8%, Deccox-L is 0.5%, our Crypto SD is 0.5% and then there is 6% Deccox. The dosage for the 6% is ½ -level teaspoonful. We use a heaping tablespoonful for the 0.5% and 0.8% products. I really dislike the Deccox-M and Deccox-L. The base is soluble lactose and the calf feeder assumes everything went into solution, when it really did not. You just don’t see the 50mg (a toothpick full) of decoquinate lying in the bottom of the bucket. Due to its assumed solubility, calf raisers bulk mix, resulting in the last calf fed, getting all the medicine. Decoquinate is extremely safe and non-toxic. It is not absorbed from the gut.
There are many other medications used for Crypto. Corid is totally ineffective against Crypto and a little over dose ties up thiamine and the calves develop polio, “star gazers.