“Biosecurity” is a term that was used extensively after 9-11. Outbreaks of foot and mouth disease and B.S.E. in Europe had everyone in the livestock industries in America cautious..
“Biosecurity” is actually just a fancy way of saying “common sense” as it refers to preventing disease introduction into a herd. Calf diarrhea or calf scours is a disease entity that can transported onto a cow calf ranch when common sense should intervene and help prevent the introduction of new calf scour pathogens.
South Dakota State University researchers (W. B. Epperson. 2003 South Dakota Beef Report) examined the cause of a scours epidemic in one spring calving herd back in 2000. Results of the retrospective, record-based investigation suggested that introduction of foster calves was associated with the calf scours outbreak. Prior to April 5, no scours cases had been observed, despite 39 calves being born. The calf scours epidemic was clearly in swing by the 45th day of the spring calving season and first cases of the epidemic were observed between the 31st and 40th days (April 5, through April 14, 2000). Following April 5, records indicated there was the introduction of at least 2 foster calves. The outbreak commenced shortly after the introduction of foster calves. Foster calves can introduce pathogens to a herd, and can shed calf scours pathogens in their feces even when feces appear normal. Because of this risk, the introduction of foster calves is not usually recommended. If introduced into a herd, foster calves (with their foster dam) should be isolated from the remainder of the herd until all calves are at least 4 weeks old. At that time, it is generally regarded as safe to commingle foster calf pairs with the remainder of the herd.
Anytime new cattle are purchased and brought onto the ranch, biosecurity guidelines (aka: common sense) need to apply. Isolate the new animals for a period of about one month before turning them into pastures with other cattle. Visit with your local large animal veterinarian about recommended tests as well as vaccinations or parasite controls that can implemented on the new arrivals before exposing them to the remainder of the herd.