Ixodes spp. (cattle)
Category:
Species:
Ectoparasite
Description:
Ixodes spp.
Castor-bean tick, russet tick, paralysis tick, shoulder tick, black-legged tick
General Description:
Inornate tick without eyes or festoons. Palpi are long. Anal groove surrounds front of anus.
Life Cycle:
The castor bean tick, I. ricinus, is a three-host tick, the life cycle of which covers three years. Unfed larvae can survive 13 to 19 months; nymphs and adults may last 24 and 21 to 27 months, respectively, without food. The paralysis tick of South Africa (I. rubicundus) has a 2-year life cycle with specific requirements of temperature and humidity. Engorged females lay eggs over a 6 week period in spring and summer. Hatching depends on humidity of at least 80 percent. Larvae are active in autumn and winter; greatest activity occurs in the spring.
Location:
Anywhere on skin of host; Ixodes scapularis often occupies shoulder areas while I. rubicundus prefers lower parts of legs and abdomen.
Geographical Distribution:
Worldwide, with some species confined to certain countries.
Significance:
In addition to spreading disease organisms and causing debilitation, Ixodes species are a primary cause of tick paralysis.
Effect on Host:
Abscess formation from tick bites weakens the skin of carcasses. Tick worry causes decreased growth. Anemia may occur with heavy infestations. The castor-bean tick transmits redwater fever (Babesia divergens, Babesia bovis) transovarially, and anaplasmosis (Anaplasma marginale). Ixodes holoeyelus transmits Q fever (Coxiella burnetti) .
Diagnostic Information:
Ixodes adults may be identified on cattle.
Control:
Chemical treatment of cattle has been the only means of reducing Ixodes populations.
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