Rhipicephalus spp.

R spp are mostly three host ticks, although some have a two host life cycle. They are commonly found on mammals but rarely infest reptiles and birds. These species were previously indigenous to the 'Old World', but have now been spread to a range of habitats worldwide and are important vectors of several infectious agents. They can generally be identified by:

• Short, wide palps
• Hexagonal base of capitulum
• Eyes present on idiosoma
• Not ornate
• Festoons on posterior margin
• Posterior anal groove
• Comma shaped spiracles

Rhipicephalus sanguineus

Also known as:

Brown dog tick Kennel tick

This species is found throughout the world, mainly affecting dogs but also found on other mammals and birds including humans. In dogs its main predilection sites are behind the ears and between the toes. In the UK these ticks are found in houses and kennels as the outdoor conditions are not suitable, however in warmer climates the ticks can be found outdoors. This adult tick is yellow/brown in colour, while larvae are light brown and nymphs reddish. The adults can vary in size from 3mm up to 12mm in the engorged female. It is a three host tick and can complete its life cycle in 4 - 5 months, though this may take longer in colder conditions. Mating takes place on the host and once inseminated the female will feed for a number of days before shedding from the host. She will then lay approximately 4000 eggs in raised, sheltered spots and so eggs can often be found in kennel roof spaces. In dogs this tick can cause paralysis as well as acting as a vector for Lyme disease (Borrelia burgdorferi), Babesia canis, B.gibson, Ehrlichia canis, E.vogeli, Salmonella enteritidis, Hepatozoon canis, Rickettsia conorii, Q fever, as well as Rickettsia rickettsii (Rocky mountain spotted fever) in parts of the USA and Mexico.

Overseas Species

Rhipicephalus microplus

Also known as:

Boophilus microplus Tropical cattle tick Southern cattle tick

This is considered the most serious external parasites of Australian cattle, though they also affect cattle accross the southern hemisphere and the southern states of the USA. It is able to complete its life cycle in just 2 months under optimal conditions and lay 2000 - 3000 eggs during this time. It is important in its ability to act as a vector for Babesia bigemina, Borrelia theileri in South America and in Australia of Coxiella burnetti and Anaplasma marginale. These organisms can be passed down for up to 5 generations of ticks regardless of the hosts on which they feed as they can be passed transovarially between generations.

• Warmer climates
• Causes paralysis in livestock
• Vectors for diseases such as
  • Theileria parva which causes East Coast Fever
  • Babesia bigemina which affects ruminants, mainly in Africa
  • Babesia canis and Ehrlichia canis which affects dogs in warmer climates worldwide