However, most pathogens associated with diarrhea were viral or protozoan in surplus calves (Renaud et al., 2020). Diarrhea onset therapyOne opportunity explored is feeding calves at diarrhea onset. For younger calves at-risk for diarrhea, feeding colostrum at 0.13 kg/day for 3 days at onset ameliorated diarrhea severity. The intervention feeding of colostrum to calves at a rate of 0.15 kg/day for 4 days at diarrhea onset decreased diarrhea severity and improved ADG compared to control calves. Calves benefit both from preventative feeding of colostrum and intervention colostrum feedings, but the mechanisms behind why calves receiving colostrum are more disease-resilient have not been researched.