An overview of calf diarrhea - infectious etiology, diagnosis, and intervention

Cho, Yong-il; Yoon, Kyoung-Jin

Dystocia is closely related to poor calf performance as well as increased susceptibility to environmental pathogens which frequently cause calf diarrhea [71] . Calves that experience dystocia may have physical symptoms such as congestion and swelling of the head and tongue, which can reduce the amount of colostrum uptake from the dam. The absorption rate of colostrum-derived immunoglobulin is lower in these calves compared to healthy animals [98] . Consequently, the affected calves cannot obtain appropriate passive immunity from the dams due to inadequate colostrum uptake during early life (i.e., 2~ 6 h after birth) [92] . The major causes of dystocia are associated with large calf size and small pelvic size of the dam. Large calves are more likely to have an improper position and presentation (e.g., backward, breech, and mal-positioned limbs or head) in the uterus. Under these conditions, the head and legs cannot enter the birth canal. Insufficient maternal pelvic size also can induce dystocia, especially in beef heifers. To prevent dystocia, the dam's genetic inheritance (e.g., adequate pelvic size and calving ease) should be taken into consideration during heifer selection [9] , and frequent monitoring of the calving cow is required for appropriate calving assistance [71] .