Ectoparasites of Domestic Animals

In July 2008 a survey of ectoparasites on domestic animals was conducted in the Royal Thai Army areas of operation along the Thai-Myanmar Border, Tak Province, Thailand. Eleven different ectoparasites were collected: two species of hard ticks (Ixodidae), three species of fleas (Siphonaptera) and 6 species of sucking or chewing lice (2 species each in the suborders Anoplura, Ischnocera and Amblycera) were collected. Domestic dogs (Canis lupus familiaris) (n=94) were found infested with 2 species of flea Ctenocephalides felis orientis (86.2%) and Echidnophaga gallinacea (1.1%), one species of tick, Rhipicephalus sanguineus (21.3%), and one louse species, Heterodoxus spiniger (7.4%). Domestic cats (Felis catus) (n=6) were found infested with only flea species, Ctenocephalides felis felis (100%) and E. gallinacea (33.3%). Cattle (Bos indicus) (n=11) had Rhipicephalus (Boophilus) microplus (72.7%), Linognathus vituli (27.3%), and Solenopotes capillatus (9.1%) present, while chickens (Gallus domesticus) (n=10) had infestations with E. gallinacea (20%), and 3 lice species, Lipeurus caponis (10%), Goniodes dissimilis (10%) and Menopon gallinae (60%). This is believed to be the first report of S. capillatus collected in Thailand. compromised by irritation, hypersensitivity, dermatoses and alopecia. The presence of salivary and fecal antigens from burrowing ectoparasites (eg, Sarcoptes) can result in significant hypersensitivity in some animals. Feeding activity of the ectoparasites may result in significant blood loss, secondary infestations, pruritus, excoriation and in some cases premature death. Ectoparasites may also cause indirect harm including behavioral disturbances, such as increased frequency of rubbing or scratching, leading to reduced time in feeding. For cattle, less grazing and general disturbed behavior decreases production of meat or milk (Matthysse, 1946). In some cases, infected animals may resort to self-wounding, particularly when ectoparasites are present in INTRODUCTION Arthropod ectoparasites have a major impact on husbandry, productivity and welfare of domestic animals (Colebrook and Wall, 2004). These obligate parasites live, feed and shelter on or just beneath the surface of their host’s epidermis, hair or feathers (Marshall, 1981). As a result, skin and other subcutaneous tissues can be directly SOUTHEAST ASIAN J TROP MED PUBLIC HEALTH 436 Vol 40 No. 3 May 2009 high densities (Berriatua et al, 2001). Some ectoparasites may also act as vectors of viruses, rickettsia, bacteria, protozoa, cestodes and nematodes, including vectors of zoonotic diseases in humans (Arends et al, 1990; Uilenberg, 1995; Raoult and Roux, 1997; Parola et al, 2003, 2005; Rehbein et al, 2003; Petney et al, 2007). Various studies have reported ectoparasites on domestic animals in Thailand, including dogs (Sangvaranond, 1990a,b; Sangvaranond et al, 2000; Nithikathkul et al, 2005), domestic cattle (Sangvaranond, 1988; Sarataphan et al, 1998), and chickens (Sangvaranond, 2003). Tanskul et al (1983) and Ahantarig et al (2008) have published checklists and summarized disease information regarding ticks in Thailand. The Thai-Myanmar border in Tak Province has experienced an increase in cross border movements and importation of large numbers of livestock from Myanmar into Thailand (Tanya, 2001). The economic impact from changes in animal husbandry and the need for increased parasite surveillance and control have increased the need for a better understanding of the current distribution and prevalence of livestock and domesticated animal ectoparasites. This paper describes a survey of ectoparasites on domestic animals in military operational areas along the Thai-Myanmar border of Tak Province, Thailand. MATERIALS AND METHODS This study was conducted in 28 military areas of operation along the Thai-Myanmar border with Tha Song Yang, Mae Ramat, Mae Sot and Phop Phra districts of Tak Province, Thailand in July 2008 (Fig 1). The ectoparasites were collected from 4 species of domestic animals including dogs (Canis lupus familiaris), cats (Felis catus), chickens (Gallus domesticus) and native cattle (Bos indicus). All animals were humanly captured and handled during the inspection process. Skin, hair shafts, feathers, ears, and other locations were carefully inspected. Fleas were collected by combing the coats of the animals with flea combs. The presence of Fig 1–Area of ectoparasite collections, Tak Province, Thailand. ECTOPARASITES OF DOMESTIC ANIMALS Vol 40 No. 3 May 2009 437 ticks and lice were detected either by visual examination or by brushing the coat and collected them using forceps. The ectoparasites found were preserved in 70% ethyl alcohol in a sample tube. Lice and flea samples were placed directly in Hoyer’s medium (Krantz, 1981) while tick samples were examined directly under a stereoscope. The specimens were identified to species according to published methods and taxonomic keys (Furman and Catts 1982; Varma, 1993; Price and Graham, 1997). Species names for the Ixodid ticks followed the revisions by Horak et al (2002). Host animals were not sampled for other mites, particularly the species in the suborder Gamasida, eg, Ornithonyssus, Dermanyssus, Sarcoptes, Otodectes, Notoedres, Demodex, and Cheyletiella species.