Cryptosporidium parvum is a zoonotic apicomplexa-protozoan pathogen that causes gastroenteritis and diarrhoea in mammals worldwide. The organism is transmitted by ingestion of oocysts, which are shed in faeces, and completes its lifecycle in a single host.^1^ C. parvum is ubiquitous on dairy operations worldwide and is one of the leading causes of diarrhoea in calves on these farms.^2,3^ Here, for the first time, we describe the antibody response in a large group of cows to a recombinant C. parvum oocyst surface protein (rCP15/60) vaccine and the antibody response in calves fed rCP15/60-immune colostrum produced by these vaccinated cows. Results of recent genotype surveys indicate that calves are the only major reservoir for C. parvum infections in... |