June 2024
New Escherichia coli Targets: Neonatal Diarrhea PCR Panel
KSVDL has added another E. coli genotype target to our bovine neonatal diarrhea panels (MDL-7100 and MDL-7102).
The panel had previously contained E. coli genotype F5 (in the past designated K99). After completing extensive internal and external research, KSVDL has added genotype F41 as a target to enhance the value of the assay.
The F designations indicate the presence and type of fimbriae (also called pili). The fimbriae enable E. coli to bind to and colonize the intestinal epithelium allowing them to produce enterotoxins leading to diarrhea. The degree of colonization is believed to determine if infection will proceed to disease.1,2
E. coli is the likely causative pathogen in very early (1-5 DOA) bovine diarrhea cases and its importance should be recognized when designing scour mitigation programs. As always, when interpreting PCR neonatal diarrhea results, consideration of the cycle time (Ct) levels and calf age are key to a correct diagnosis.
References:
- Dubreuil, J. Daniel, Richard E. Isaacson, and Dieter M. Schifferli. "Animal enterotoxigenic Escherichia coli." EcoSal Plus1 (2016): 10-1128.
- Nagy, Béla, and Péter Zs Fekete. "Enterotoxigenic Escherichia coli (ETEC) in farm animals." Veterinary research2-3 (1999): 259-284.