Cryptosporidium spp - This parasite is similar to most coccidia except that the organism is not considered to be host specific and is located in parasitophorous vacuoles just under the surface membrane of host cells or within its striated border rather than within host cells. Transmission is by the fecal-oral route. There are many species of Cryptosporidium capable of infecting many animals. Clinical cryptosporidial infections in calves are characterized by diarrhea often occuring around the second week of life. Appetite usually remains good and dehydration is minimal in uncomplicated cases.
Stools often have a rancid odor, a yellow to white color and are putty-like in consistency.
Cryptosporidia infections are among the four most common pathogens associated with neonatal diarrhea in calves. It is common in both beef and dairy calves as well as lambs. The organism appears to have a worldwide distribution. Zoonotic infections in humans are common. In most cases, diarrhea is the clinical problem resulting from infection.