Ticks Mites Lice and Fleas

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Parasitic Infestation in animals is a major cause of loss in the health of animals. Parasites can be found from cattle to goats, to dogs, cats, and humans as well and the list goes on ” n” on. This article is about ticks, mites, lice, and fleas which are a small part of a bigger parasitic problem in animals.

Ticks

Ticks are blood-sucking parasitic arachnids that belong to the superorder of Parasitiformes, of the phylum Arthropoda. They are further classified as Hard (Ixodidae) and Soft (Argasidae)Ticks based on the presence of an outer hard shield. Ticks are eight-legged (four pairs) parasites, which have four staged life cycle which includes an egg, six-legged larvae (seed tick), eight-legged nymph, and, eight-legged adult. They require multiple hosts to complete their life cycle i.e. Heteroxenous parasite. Cats, dogs, horses, rabbits, and, humans are parasitized.

Ticks as vectors of several zoonotic diseases are ranked second only to mosquitoes as vectors. The diseases spread by ticks are a major constraint to animal productivity while causing morbidity and mortality in both animals and humans. A number of tick species have been recognized for long as vectors of lethal pathogens, viz. Crimean-Congo hemorrhagic fever virus (CCHFV), Kyasanur forest disease virus (KFDV), Babesia spp, Theileria, Rickettsia conorii, Anaplasma marginale, etc. and the damages caused by them are well-recognized. Ticks and Ticks borne diseases (TTBDs) in cattle and buffaloes are frequently heavily infested, which apart from transmitting diseases such as theileriosis, babesiosis, and anaplasmosis, also cause extensive damage to the livestock health and production.

Diagnosis is mainly done by Clinical Signs exhibited by animals, Serological Tests, ELISA (IgM) capture assay, Indirect immunofluorescence assay. Control Measures are important in controlling the TTBDs, vaccines such as TickGARD, GAVC, Chemical control methods can be used to limit the disease.

Lice

Lice (Phthiraptera) are wingless, blood-feeding, or skin-chewing ectoparasites, which belong to the Arthropoda phylum of the animal kingdom, that are a danger to pets, livestock, and humans.  There are 3200 known species of lice that infect wild birds or animals but only a small percentage has any known medical or veterinary importance. There are two important groups among lice, blood-sucking (Anoplura), and chewing lice(Mallophaga).

Adult lice are small (0.4 – 10 mm), wingless, and dorso-ventrally flattened.  The female glues her eggs (nits) onto the host’s hair or feathers. There can be 10-12 generations a year.  Bloodmeal is essential for the development and survivorship of all sucking lice while chewing lice can survive several days off the host. Metamorphosis is incomplete in the life cycle.

Menopon gallinae, Columbicola columbae, are bird-biting lice while Damalinia spp. is ruminant biting lice. Trochodectes canis, Heterodoxus spiniger are Dog biting lice, Felicola subrostratus is found in cats.

Lice in various animals cause different disorders such as anemia, dermatitis, pruritus (itchy skin), hair loss, allergies, and in some cases lameness. In milch animals, it leads to low milk yield. In Equines, coat deterioration and hair loss are experienced along with other signs.

Diagnostics involved Direct Microscopy(DMC) of the skin scrapping sample collected from the infested site (skin, hairs). The presence of Nits or Lice Confirms the infestation.

Control and Prevention – Clipping of matted hairs and wool, Using a Flea comb for companion animals, Flea shampoo. Topical application of Fipronil, Selamectin, Amitraz(in cattle). Ungrouping of the animal also shows great results in controlling the spread among animals.

Mites

Mites are small arachnids (eight-legged arthropods), have six-legged larvae hatch from fusiform-shaped eggs, and which undergo several molts to become eight-legged nymphs and ultimately adults. All stages of the life cycle (eggs, larvae, nymphs [protonymph, deutonymph], adults) reside within the lumen of hair follicles and within sebaceous gland ducts, and some species are found in the stratum corneum. Elongated mites are often described as Cigar-shaped.

Demodex spp. is found in the hair follicles in the skin. They crawl from the dam to the newborn pup or kitten, during the first few days of life. They don’t cause any harm in small and are considered normal inhabitants of the skin. These mites are not contagious from animals to animals, or animals to humans. The skin disease is caused by the increased number of mites is called Demodicosis or demodectic mange. It is rare in cats.

Except for Poultry mites (Dermanyussus gallinae) are visible to naked eyes, while others are microscopic.

Skin scrapping or removal of the superficial layer of a small area of skin with a scalpel blade is made using mineral oil and examined under a microscope.

Flea

Fleas are wingless, brown, blood-sucking insects that may infest dogs and cats, and other warmblooded animals. Fleas transmit several diseases such as plague) and parasites such as tapeworms. Young animals heavily infested with fleas may die from severe blood loss.

Flea eggs laid on the host are smooth and quickly fall off into the animal’s environment. The eggs are oval, white, and glistening. Small larvae hatch from the eggs and feed on the feces from adult fleas. After several molts, the last larval stage forms a pupal case while in this case, the larva develops into an adult flea. The adult flea emerges from the pupal case and searches for an animal. fleas move rapidly on the skin and are most easily found on the rump and in the groin area.

Flea saliva when deposited in the skin each time the adult flea bites an animal, which leads to irritation and an allergic reaction can cause severe itching, resulting in the skin disease termed flea allergy dermatitis. Biting and scratching around the rump and groin areas is the most common sign of flea allergy. Hair loss, a red rash, and thickening of the skin are commonly seen.

Successful treatment of flea allergy dermatitis requires the absolute elimination of fleas from contact with the affected dog or cat. Frontline as a spot-on and Simparica (chewable) can be given to treat flea infestation.

Say no to Fleas and Ticks

THE GEEK VETERINARIAN