A U.S. Isolate of <i>Theileria orientalis</i> Ikeda Is Not Transstadially Transmitted to Cattle by <i>Rhipicephalus microplus</i>

Theileria orientalis Ikeda has caused an epidemic of bovine anemia and abortion across several U.S. states. This apicomplexan hemoparasite is transmitted by Haemaphysalis longicornis ticks; however, it is unknown if other North American ticks are competent vectors. Since the disease movement is largely determined by the host tick range(s), the prediction of the T. orientalis spread among U.S. cattle populations requires determination of additional competent tick vectors. Although Rhipicephalus microplus has mostly been eradicated from the U.S., outbreaks in populations occur frequently, and the U.S. remains at risk for reintroduction. Since R. microplus is a vector of Theileria equi and T. orientalis DNA has been detected in R. microplus, the goal of this study was to determine whether R. microplus is a competent vector of T. orientalis. Larval R. microplus were applied to a splenectomized, T. orientalis Ikeda-infected calf for parasite acquisition, removed as molted adults, and applied to two T. orientalis naïve, splenectomized calves for transmission. After 60 days, the naïve calves remained negative for T. orientalis by PCR and cytology. Additionally, T. orientalis was not detected in the salivary glands or larval progeny of acquisition-fed adults. These data suggest that R. microplus is not a competent vector of the U.S. T. orientalis Ikeda isolate

<i>Dermacentor variabilis</i> Does Not Transstadially Transmit the U.S. Isolate of <i>Theileria orientalis</i> Ikeda: A Controlled Acquisition and Transmission Study

Theileria orientalis Ikeda, an emerging U.S. bovine hemoparasite, causes anemia, abortion, ill-thrift, and occasionally death. While Haemaphysalis longicornis is the primary vector, it is possible that other U.S. ticks are capable of parasite transmission and may contribute to disease spread. Dermacentor variabilis is highly prevalent in the U.S., exhibits a similar geographical distribution to T. orientalis, and is a competent vector of the related parasite, Theileria equi. Herein, we conducted controlled acquisition and transmission studies using splenectomized calves to assess whether D. variabilis can transstadially transmit T. orientalis. D. variabilis nymphs were applied to an infected, splenectomized calf for parasite acquisition and subsequently incubated to molt into adults. Freshly molted adults were applied to two splenectomized T. orientalis-naïve calves to investigate parasite transmission. Calves were monitored for 59 days, and no evidence of parasite transmission was detected using PCR for the T. orientalis Ikeda major piroplasm surface protein gene, blood smear cytology, complete blood counts, or physical examination. Salivary glands from a subset of D. variabilis adults were assessed for T. orientalis using PCR, and the parasite was not detected. These findings support the conclusion that D. variabilis is not capable of transstadial transmission of the U.S. T. orientalis Ikeda isolate

Data for Kenyan pigs

This Zip file has a README file that provides a complete description of the data

Sample populations, source project and sample utility in the project.

<p>Sample populations, source project and sample utility in the project.</p

Plots of selective sweep patterns for various pig populations.

<p>The -log10(FDR-adjusted P) values are plotted against chromosome number. The dashed lines indicate the significance threshold for the top 1% SNPs based on with |iHS| value. Selective sweeps (iHS) for (5A) Bush pigs, (5B) Homabay, (5C) for Busia population and warthogs.</p

Admixture plot representing estimated membership coefficients for individual pigs for ancestral populations (K) ranging between 2 to 9.

<p>Admixture plot representing estimated membership coefficients for individual pigs for ancestral populations (K) ranging between 2 to 9.</p

The number of pigs that tested ASFv positive and negative given their local pig ancestry proportions.

<p>The number of pigs that tested ASFv positive and negative given their local pig ancestry proportions.</p