Posted by Dr. Sara Barber on June 15 2009 12:06
Cryptosporidium is an intestinal parasite that can affect many species. The calves become infected when they eat infectious oocysts (Crypto eggs) from feces or contaminated feed or water. The infected calves will shed large numbers of oocysts which can infect other calves. Crypto is very contagious and it only takes a few oocysts to infect a calf or a human.
Calves infected with Crypto have diarrhea and can get very dehydrated. The diarrhea usually lasts for 5-10 days. Crypto generally causes diarrhea in calves from 7-21 days of age.
Calves who did not receive enough colostrum are more susceptible to Crypto. Also, if the calves are infected with another pathogen such as E. coli, Salmonella, Coccidia, or Rotavirus they are more likely to become infected with Crypto.
There are no vaccines available for Crypto prevention. The best prevention is excellent sanitation in the calf barn. The calf pens need to be washed and disinfected between calves. Bottles, nipples, esophageal feeders, and buckets should be washed in warm, soapy water and rinsed with a bleach solution between calves.
Antibiotics have no effect on Crypto. The most important element of treatment is oral electrolytes. Keep the calves on milk and give them 2 quarts of a balanced electrolyte, such as CDT, four hours after feeding milk. They may need another electrolyte feeding four hours after the second milk feeding if they are extremely dehydrated.
There are a few extra-label medications which have been helpful in preventing and treating Crypto. Crypto Relief is a liquid medication which is added to the milk or milk replacer to prevent Crypto. The dose for a Holstein calf is 2 cc per 100 pounds twice a day for the first 14 days of age. This medication may need to be continued if Crypto problems extend beyond 14 days of age.
For treating Crypto infections, a product called Coxuril has been very helpful. The dose is 30 cc in the milk once a day for 5 days.