Blood feeding of Ornithodoros turicata larvae using an artificial membrane system

Authors: KIM, HEE - Texas A&M Agrilife; FILATOV, SEHRI - National Scientific Center; LOPEZ, JOB - Baylor College Of Medicine; Perez De Leon, Adalberto - Beto; TEEL, PETE - Texas A&M Agrilife

Submitted to: Medical and Veterinary Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/31/2016
Publication Date: 6/1/2018
Citation: Kim, H., Filatov, S., Lopez, J., Perez De Leon, A.A., Teel, P. 2018. Blood feeding of Ornithodoros turicata larvae using an artificial membrane system. Medical and Veterinary Entomology. 31(s):230-233.

Interpretive Summary: The design and testing of artificial systems to feed ticks can help refine laboratory experiments and reduce the use of animals as a blood meal source. An artificial membrane system was adapted to feed immature soft ticks of the species Ornithodoros turicata, more specifically larvae, in the laboratory. This soft tick species can transmit disease agents that affect humans and animals. Swine blood was used to feed soft tick larvae in the laboratory with the artificial membrane system. Aspects related to larval feeding and the process to grow, or molting, to the next life stage, or first nymphal instar, were evaluated. Fifty-five percent of all larvae exposed to the artificial membrane in two experimental groups fed to repletion and 97% of all fed larvae molted. However, the instrument used to sort the larvae appeared to influence their viability. Mortality among the group of fully blood-fed and newly-molted larvae sorted with forceps was more than three times that of the group sorted with camel-hair brushes, which resulted in an overall 27% yield increase of first instar nymphs in the group sorted with camel-hair brushes. Different physical properties between the forceps and camel-hair brushes may affect the viability of the fragile soft tick larvae even when care and the same technique are used to sort them during experimental manipulations. Our results represent the first report to quantify successful feeding to repletion, molting, and post-molting mortality rates for O. turicata larvae using an artificial membrane feeding system. Applications of the artificial membrane feeding system to fill gaps in our knowledge of soft tick biology and the study of soft tick-disease agent interactions are discussed.

Technical Abstract: An artificial membrane system was adapted to feed Ornithodoros turicata larvae from a laboratory colony using defibrinated swine blood. Aspects related to larval feeding and molting to the 1st nymphal instar were evaluated. Fifty-five percent of all larvae exposed to the artificial membrane in two experimental groups fed to repletion and 97% of all fed larvae molted. However, the instrument used to sort the larvae appeared to influence their viability. Mortality among the group of engorged and newly-molted larvae sorted with forceps was more than 3 times that of the group sorted with camel-hair brushes, increasing the overall yield of 1st instar nymphs by 27% in the group sorted with camel-hair brushes. Different physical properties between the forceps and camel-hair brushes may affect the viability of the fragile soft tick larvae even when care and the same technique are used to sort them during experimental manipulations. Our results represent the first report to quantify successful feeding to repletion, molting, and post-molting mortality rates for O. turicata larvae using an artificial membrane feeding system. Applications of the artificial membrane feeding system to fill gaps in our 38 knowledge of soft tick biology and the study of soft tick-pathogen interactions are discussed.