Systematic Review of Ticks and Tick-Borne Pathogens of Small Ruminants in Pakistan

Abstract

Ticks and tick-borne diseases (TTBDis) are a major constraint to the health and production of small ruminants in Pakistan. Despite being the subject of intermittent studies over the past few decades, comprehensive information on the epidemiology and control of TTBDis is lacking. Herein, we have systematically reviewed the current knowledge on TTBDis of small ruminants in Pakistan. Critical appraisal of the selected 71 articles published between 1947 to 2020 revealed that morphological examination had been the most widely used method for the identification of TTBDis in Pakistan. Tick fauna comprise at least 40 species, mainly belonging to Haemaphysalis, Hyalomma and Rhipicephalus. The prevalence of ticks is the highest in summer (June–September) and it is also higher in goats than sheep. Anaplasma, Babesia and Theileria spp. are the major tick-borne pathogens (TBPs), and their prevalence is usually higher in sheep than goats. Spatio-temporal distribution, genetic diversity and control of ticks and TBPs of small ruminants as well as the competence of tick vectors for various TBPs remain to be explored. Therefore, coordinated and focused investigations are required to fill knowledge gaps in these areas to maximise the health, production and welfare of small ruminants and minimise economic losses associated with TTBDis in Pakistan.

Diversity and Genetic Structure of Theileria annulata in Pakistan and Other Endemic Sites

“…Nonetheless, there was some overlap between parasites in Tunisia and Oman, indicating that the separation between the parasite populations in the two countries was incomplete ( Figure 1 B). Similar incomplete separation has been previously reported in T. annulata populations from widely separated countries [ 7 , 20 ]. These observations suggest that despite ecological and epidemiological barriers between the different parasite populations, gene flow occurs between the above countries, probably due to the movement of animals, often as an asymptomatic infection and infesting ticks.…”

“…The parasites in these four countries tend to form genetically distinct groups with some geographical sub-structuring (Figures 1B and 2). The relatively lower level of genetic differentiation detected between T. annulata from Pakistan and Oman (F ST = 0.09) when compared with that observed between Pakistan and Tunisia (F ST = 0.1293) and Pakistan and Turkey (F ST = 0.166), is consistent with the pattern of a high level of differentiation documented between samples of T. annulata from Oman and Tunisia (F ST = 0.06855) and from Oman and Turkey (F ST = 0.1092) [20]. Similar observations regarding the genetic diversity of T. annulata have been reported in a recent study from India by Roy et al [6].…”

“…(3), with multiple species distributed across a wide geographical spectrum (Southern Europe, North Africa, East Asia). While H. anatolicume is the main vector in the study sites, many additional species of Hyalomma exist in some [ 18 , 20 , 22 ]. The variation in the intrinsic characteristics of these ticks, such as feeing behavior, can influence their transmissibility capacity and the extent of diversity of T. annulata over the study regions.…”

Epidemiology of Ectoparasites (Ticks, Lice, and Mites) in the Livestock of Pakistan: A Review

“…In addition, grooming, which is the manual plucking of ticks by agricultural workers, is a popular practice in Pakistan for tick management ( 63 ). However, only two studies have evaluated the efficiency of acaricidal medicines in vivo , and the authors reported that cypermethrin was the most efficient tick control drug in livestock ( 59 , 64 ). Numerous studies have been conducted to determine the efficiency of different medicines (alone or in combination with antibiotics) in treating ectoparasites, including buparvaquone, diminazene aceturate + imidocarb dipropionate, and oxytetracycline ( 65 ).…”

Association of Hard Ticks (Ixodidae) Infestation with Milk Production and Udder Health of Extensively Reared Dairy Goats

“…In extensively reared goats, tick infestation is identified as a major epidemiological issue, especially in tropical and subtropical regions [16]. A high diversity of hard tick species infesting goats has been reported in Middle East and North Africa [17] and a prevalence of circa (ca.)…”