Source: Kansas Livestock Association
The Kansas State Veterinary Diagnostic Laboratory (KSVDL) is warning livestock producers about Theileria orientalis Ikeda, a red blood cell parasite recently detected in calves imported to Kansas. This parasite causes theileriosis, leading to anemia, weakness, difficulty breathing, and, in severe cases, death, with mortality rates reaching up to 30%.
The disease is primarily transmitted through multi-use needles and insect vectors, particularly the Asian longhorned tick, which has been found in Missouri, Arkansas, and northwestern Oklahoma. Other blood-feeding flies, such as horse, stable, and deer flies, may also spread the parasite.
Since Theileria is highly resistant to antibiotics, KSVDL recommends testing all cattle imported from eastern states before arrival in Kansas. A blood test is available for early detection. To prevent herd transmission, producers should adopt single-use needles, disinfect tattoo and ear tag pliers, and implement a strong fly, tick, and lice control program to mitigate risks.