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The soft ticks are only of importance in warmer climates, whereas the hard ticks cause significant problems in both warmer and temperate climates.
The soft ticks are only of importance in warmer climates, whereas the hard ticks cause significant problems in both warmer and temperate climates.
==Morphology==
==Morphology==
===Hard Ticks===
===Hard ticks===
*Hard, chitinous covering over dorsal surface called the '''scutum'''
*Hard, chitinous covering over dorsal surface called the '''scutum'''
*Enamel coloured patches on scutum are present on '''ornate ticks'''
*Enamel coloured patches on scutum are present on '''ornate ticks'''
*Female hard ticks may swell up to three times their normal size when taking a blood meal
*Female hard ticks may swell up to 3 times their normal size when taking a blood meal
===Soft Ticks===
===Soft ticks===
*No scutum
*No scutum
*Feed little and often as cannot swell as much as hard ticks
*Feed little and often as cannot swell as much as hard ticks
==Mouthparts==
==Mouthparts==
*The '''hypostome''' pushes through the wound made by the chelicerae where backwards pointing teeth lock the mouthparts into the skin
*The '''hypostome''' pushes through the wound made by the chelicerae where backwards pointing teeth lock the mouthparts into the skin
**Dorsal groove in the hypostome permits the flow of tick saliva and host blood
**Dorsal groove in the hypostome permits the flow of tick saliva and host blood
==Feeding==
==Feeding==
*Host tissue is broken down leaving a zone of necrosis creating a '''feeding lesion'''
*Host tissue is broken down leaving a zone of necrosis creating a '''feeding lesion'''
==Life Cycle==
==Life cycle==
*Ticks are temporary parasites so only spend a short period of their lives on the host species
*Ticks are temporary parasites so only spend a short period of their lives on the host species
*Both hard and soft ticks have the same life cycle
*Both hard and soft ticks have the same life cycle
**Egg - larva - nymph - adult
**Egg → larva → nymph → adult
*Soft ticks feed little and often and on '''many hosts'''
*Soft ticks feed little and often and on '''many hosts'''
'''Hard Ticks'''
'''Hard ticks'''
*Classified depending on the number of host species they parasitise during their life cycle
*Classified depending on the number of host species they parasitise during their life cycle
**E.g. ''Ixodes spp.''
**E.g. ''Ixodes spp.''
==Disease Transmission==
==Disease transmission==
*'''Trans-ovarian transmission'''
*'''Trans-ovarian transmission'''
**It is '''not''' passed onto the next generation through the egg
**It is '''not''' passed onto the next generation through the egg
==Ticks of Veterinary Importance==
==Ticks of veterinary importance==
[[Image:Ticks mating.jpg|thumb|right|150px|''Ixodes ricinus'' mating - Wikimedia Commons]]
[[Image:Ticks mating.jpg|thumb|right|150px|''Ixodes ricinus'' mating - Wikimedia Commons]]
===Important UK Hard Ticks===
===Important UK hard ticks===
''Ixodes ricinus''
*3 host tick
*Life cycle takes an average of 3 years to complete (range of 2-7 years)
*Only feed for a few days each year at each life cycle stage
*Most of their time is spent on the ground
*Adult female lays several thousand eggs on the ground in matted vegetation
**E.g. Rough pasture, hedgerows etc.
''Ixodes canisuga''
*Host specific dog tick
*Problem in kennels
''Ixodes hexagonus''
**3 host tick
*Known as the hedgehog tick
**Life cycle takes an average of 3 years to complete (range of 2-7 years)
*Affects hedgehogs, dogs, cats, ferrets and weasels
**Only feed for a few days each year at each life cycle stage
*Common in small animal practice
''Haemaphysalis spp.''
**Host specific dog tick
*Affects cattle
**Problem in kennels
*Transmits ''Babesia major'', a relatively non-pathogenic protozoan parasite
*Uncommon
''Dermacentor spp.''
**Hedgehogs, dogs, cats, ferrets and wealels
*Affects sheep
**Common in small animal practice
*Rare
===Important overseas hard ticks===
''Ixodes spp.''
''Rhipicephalus spp.''
*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
''Boophilus spp.''
*Warmer climates
**Vectors for ''Babesia'' spp.
*Vector for ''Babesia spp.''
*Vectors for the bacteria ''Anaplasma'' which affects cattle
''Amblyomma spp.''
*Warmer climates
*Transmits ''Cowdria ruminatium'' (heartwater) in Africa
*Transmits 'Q-fever' and 'Rocky Mountain Spotted fever' in southern USA
''Hyalomma spp.''
*Warmer climates
*Old World
*Parasites a wide range of both domestic and wild animals
*Involved in the spread of ''Theileria'' and ''Babesia spp.''
**E.g. ''H. aegyptium'' is a parasite of tortoises in North Africa which has been spread around the world by the pet trade
**E.g. ''H. aegyptium'' is a parasite of tortoises in North Africa which has been spread around the world by the pet trade
===Important overseas soft ticks===
*''Ornithodoros'' spp.
''Argas spp.''
*Warmer climates worldwide
*Mainly an avian parasite but will also attack humans
*E.g. ''A. persicus'', the poultry tick, contributes to production losses in the poultry industry and also feeds on migratory birds in temperate climates
''Ornithodoros spp.''
*Warmer climates worldwide
*Found in primitive housing and sandy soil
*Vectors for relapsing fever in humans caused by ''Borrelia spp.''
*Vectors for African swine fever
''Otobius spp.''
*Warmer climates worldwide
*Inhabits the ears of cats and dogs
*Also referred to as the 'spinose ear tick'
*Can predispose animals to secondary myiasis
==Control==
==Control==
*In warmer climates where rainfall is present all year round and there is a constant high relative humidity, tick activity may be constant throughout the year
*In warmer climates where rainfall is present all year round and there is a constant high relative humidity, tick activity may be constant throughout the year
*If there is a limited vegetation mat, then tick activity will be influenced by seasonal rainfall and the vegetation transpiration
*If there is a limited vegetation mat, tick activity will mainly be influenced by seasonal rainfall and the vegetation transpiration
*In temperate climates there is usually two distinct periods of tick activity coinciding with warmer temperatures
*In temperate climates there is usually 2 distinct periods of tick activity coinciding with warmer temperatures
**E.g. Spring and Autumn
**E.g. spring and autumn
*Some temperate climates only have one distinct period of tick activity in the spring
*Some temperate climates only have 1 distinct period of tick activity in the spring
===Control methods===
*Altering microclimate
'''Killing ticks on the ground'''
*Altering micro-climate
**E.g. Pasture improvement
**E.g. Pasture improvement
*Starving (spelling) pasture
*Starving (spelling) pasture
*Burning pasture to kill off ticks on the ground
*Burning pasture to kill off ticks on the ground
'''Separate the host from the infection'''
*Stock management
*Stock management
**removing stock from infected pasture when ticks are most active
**Removing stock from infected pasture when ticks are most active
*Fencing off infected areas
*Fencing off infected areas
'''Killing ticks on the host'''
*Ascaricides
*Acaricides
*E.g. Dipping, spraying, pour-on solutions
*E.g. Dipping, spraying, pour-on solutions
*For more information on ascaricides see [[Ectoparasiticides|here]]
*For more information on acaricides see [[Ectoparasiticides|here]]
'''Enhancing host resistance'''
*Stock hybridisation
*Stock hybridisation
**E.g. Breeding the higher resistant ''Bos indicus'' with the less resistant ''Bos Taurus''
**E.g. Breeding the higher resistant ''Bos indicus'' with the less resistant ''Bos taurus''
*Vaccination against the hidden antigens in the tick's gut
*Vaccination against the hidden antigens in the tick's gut
==[[Arachnid Flashcards - WikiBugs|Arachnid Flashcards]]==
==[[Arachnid Flashcards - WikiBugs|Arachnid Flashcards]]==