Molecular Survey and Genetic Characterization of Anaplasma marginale in Ticks Collected from Livestock Hosts in Pakistan

Abstract

Ticks transmit pathogens to animals and humans more often than any other arthropod vector. The rural economy of Pakistan mainly depends on livestock farming, and tick infestations cause severe problems in this sector. The present study aimed to molecularly characterize the Anaplasma spp. in hard ticks collected from six districts of Khyber Pakhtunkhwa, Pakistan. Ticks were collected from various livestock hosts, including cattle breeds (Holstein-Friesian, Jersey, Sahiwal, and Achai), Asian water buffaloes, sheep, and goats from March 2018 to February 2019. Collected ticks were morphologically identified and subjected to molecular screening of Anaplasma spp. by amplifying 16S rDNA sequences. Six hundred seventy-six ticks were collected from infested hosts (224/350, 64%). Among the nine morphologically identified tick species, the highest occurrence was noted for Rhipicephalus microplus (254, 37.6%), followed by Hyalomma anatolicum (136, 20.1%), Rhipicephalus haemaphysaloides (119, 17.6%), Rhipicephalus turanicus (116, 17.1%), Haemaphysalis montgomeryi (14, 2.1%), Hyalomma dromedarii (11, 1.6%), Haemaphysalis bispinosa (10, 1.5%), Hyalomma scupense (8, 1.2%), and Haemaphysalis kashmirensis (8, 1.2%). The occurrence of tick females was highest (260, 38.5%), followed by nymphs (246, 36.4%) and males (170, 25.1%). Overall, the highest occurrence of ticks was recorded in the Peshawar district (239, 35.3%), followed by Mardan (183, 27.1%), Charsadda (110, 16.3%), Swat (52, 7.7%), Shangla (48, 7.1%), and Chitral (44, 6.5%). Among these ticks, Anaplasma marginale was detected in R. microplus, R. turanicus, and R. haemaphysaloides. The 16S rDNA sequences showed high identity (98–100%) with A. marginale reported from Australia, China, Japan, Pakistan, Thailand, Uganda, and the USA. In phylogenetic analysis, the sequence of A. marginale clustered with the same species reported from Australia, China, Pakistan, Thailand, Uruguay, and the USA. Further molecular work regarding the diversity of tick species and associated pathogens is essential across the country.

Spatio-Temporal Patterns of Ticks and Molecular Survey of Anaplasma marginale, with Notes on Their Phylogeny

“…In the phylogenetic tree based on bacterial 16S rRNA, the clade of A. marginale and A. ovis clustered as a sister clade to the clade of A. centrale. This relatedness is also represented by their ecological and epidemiological aspects because these three species commonly infect ruminants [24].…”

“…Knowing that this field of research has attracted attention, there are still very few available studies restricted to a few areas in Pakistan about the molecular data of ticks and Anaplasma spp. [2,8,13,18,[22][23][24]. Our previous study has demonstrated the molecular assessment of hard ticks and associated A. marginale collected from livestock hosts in the northern and central regions of Khyber Pakhtunkhwa (KP), Pakistan [24].…”

“…[2,8,13,18,[22][23][24]. Our previous study has demonstrated the molecular assessment of hard ticks and associated A. marginale collected from livestock hosts in the northern and central regions of Khyber Pakhtunkhwa (KP), Pakistan [24]. Still, similar studies are missing from the southern regions.…”

A Case Study of Photosensitivity Associated with Anaplasma spp. Infection in Cattle

“…infection. This method is widely applied for the detection of pathogens [ 33 ]; it is very sensitive at first [ 7 ] but quickly loses sensitivity following appropriate antibiotic administration. A negative result does not exclude the diagnosis, as intermittent levels of bacteremia could produce false-negative results.…”

Prevalence of different tick species on livestock and associated equines and canine from different agro-ecological zones of Pakistan

“…Rhipicephalus and Hyalomma ticks are the most common tick species prevalent in cows and buffaloes in Pakistan (19)(20)(21). According to a recent study conducted in different zones of KP (Khyber Pakhtunkhwa), Pakistan, 3 major tick species, Rhipicephalus microplus, Rhipicephalus haemaphysaloides, and Rhipicephalus turanicus, showed positive results for Anaplasma marginale, the causative agent of anaplasmosis (22). In a recent paper, future concerns about ticks and tick-borne diseases were discussed (23).…”