Prevalence and Distribution of Bovine Ticks in Abuna Gindeberet District, West Shoa, Oromia, Ethiopia

Research Article

Austin J Vet Sci & Anim Husb. 2019; 6(2): 1058.

Prevalence and Distribution of Bovine Ticks in Abuna Gindeberet District, West Shoa, Oromia, Ethiopia

Dimshasha T1* and Marzu I2

1Asalla Veterinary Regional Laboratory, Ethiopia

2Abuna Gindeberet Livestock Development and Resource Agency, Ethiopia

*Corresponding author: Dimshasha T, Asalla Veterinary Regional Laboratory, Ethiopia

Received: May 21, 2019; Accepted: July 01, 2019; Published: July 08, 2019

Abstract

A cross-sectional study was conducted with the aim of identifying and estimating the prevalence of cattle ixodid tick infestation with respect to host related factors in Abuna Gindeberet district, Western Shoa, Ethiopia. Adult ixodid ticks were collected from 384 randomly selected cattle by using forceps and preserved in separate collecting bottle with 70% ethyl alcohol. The collected ticks were identification under stereomicroscope into generas and species based on their morphology. The present study revealed that there was high tick infestation with an overall prevalence of 274 (71.35%). In the study area four genera of ixodid ticks (Amblyomma, Rhipecephalus (Boophilus), Hyalomma and Rhipecephalus) and four species (Amblyomma variegatum, Rhipecephalus (Boophilus) decoloratus, Hyalomma dromedary, Rhipecephalus evertsi evertsi) were identified with the prevalence rate of 28.39%, 65.77%, 2.42% and 3.39% respectively. All species of ticks had higher number of male, except Rhipicephalus (Boophilus) decoloratus (5:9) and they were distributed and attached with statistically significant (P‹0.05) variation among different parts of the host body. Different risk factors (age, sex, body condition score, breed and managements) were considered but age and managemental systems are statistically significant (P‹0.05). All of risk factors respective prevalence were; age (young 1.3%, adult 54.69% and old 15.36%); sex (male 32.29% and female 39.06%); body condition score (poor 22.14%, medium 46.61% and good 2.60%); breed (local 55.98% and cross breed 15.37%) and management system(extensive 68.75 % and semiintensive 2.6%). The present study indicates there is high prevalence of ixodide tick infestation, especially in local cattle breed, adult, female and medium body condition. Therefore, effective control measures should be undertaken to bring the needed health and productive animals in Abuna Gindeberet district.

Keywords: Abuna Gindeberet; Identification; Ixodid Tick; Prevalence; Stereomicroscope

Introduction

Ethiopia is believed to have the largest livestock population in Africa. This livestock sector has been contributing considerable portion to the economy of the country, and still promising to rally round the economic development of the country [1]. In Ethiopia, livestock production remains crucial and represents a major asset among resource-poor small holder farmers by providing milk, meat, skin, and manure and traction force [2]. The contribution of livestock to the national economy particularly with regard to foreign currency earnings is through exploration of live animal, meat and skin and hides [3].

Poor health and productivity of animal due to disease has considerably become the major stumbling block to the potential of livestock industry [4]. Now a day parasitism represents a major obstacle to development and utilization of animal resource. In Ethiopia, ectoparasites in ruminant cause serious economic losses to small holder farmers, the tanning industry and country as a while through mortality of animals, decreased production, downgrading and rejection of skin and hide (Waktole et al., 2015). From the ectoparasites, ticks are ranked as the most economically important of livestock in tropics including sub-Saharan Africa [5].

Ticks are small, wingless ectoparasitic arachnid arthropods that are cosmopolitan and prevalent in warmer climates. Ticks cause substantial losses in cattle production, in terms of diseases, reduced productivity and fertility and often death, and are economically the most important ecto-parasites of cattle indicates that different ticks have different predilection sites on the host’s body. Ticks suck blood; damage hides and skins introduce toxins and predispose cattle to myiasis and dermatophilosis [6]. Furthermore, they reduce body weight gains and milk yield, in addition to creating sites for secondary invasion by pathogenic organisms [7].

More significantly, ticks transmit diseases from infected cattle to healthy ones. Ticks transmit a greater variety of pathogenic microorganisms than any other arthropod vector group, and are among the most important vectors of diseases affecting animals. Ticks which are considered to be most important to health of domestic animal in Africa comprise about seven genera. Among these genera, the main tick genera found in Ethiopia include Ambylomma, sub genus Rhipicephalus (Boophilus), Haemaphysalis, Hyalomma and Rhipicephalus. The genus Ambylomma and Rhipicephalus are predominating in many parts of country, Hyalomma and sub genus Rhipicephalus (Boophilus) also have significant role [8]. Due to economic and veterinary importance of ticks, their control and transmission of tick born diseases remain challenge for the cattle industry of the world and it is a priority for many countries in tropical and subtropical regions [9].

Statement of problem

In Ethiopia, tick occupy the first place amongst the external parasites by the economic loss it incurred when they infest livestock particularly cattle. They reduce cattle productivity, such as milk yield, and increase susceptibility to other diseases [10]. Approximately 80% of cattle population of the world are at risk of tick infestation and tick born diseases [11].

Regardless of losses due to tick infestation in Ethiopia, and a number of researchers reported the distribution and abundance of tick species in different parts of the country, there is still many problems faced by livestock owners due to the ixoded ticks infestation particularly in Abuna Gindeberet. In addition, there is no work done regarding the above ecto-parasites in Abuna Gindeberet district.

Objective: The study was conducted with the objectives of to estimate the prevalence of tick infestation in the study area and to identify tick species and major risk factors for the occurrence of tick infestation.

Material and Methods

Study area

This study was conducted between March, 2018 and November, 2018 in Abuna Gindeberet district of West Shoa, Ethiopia. Abuna Gindeberet district is located at 178km away from Ethiopian capital city, Addis Ababa, to the west and 134km away from Ambo to the North. This district is located at altitude of 1000m-2300m above sea level. From this, the lowland is 1000-1500masl and the mid-high land is 1500-2300masl which covers 76,578.58. Hektar land (68%) and 36,036.97 Hektare land (32%) respectively. Abuna Gindeberet Woreda is divided into 44 Kebele Administrations out of which 42 of them are rural Kebeles while 3 of them are town administrations. The study area is particularly in the three kebeles of the district, namely: Bake Kelate, Gitire Kichu and Degatina. The first kebele, Bake Kelate, found at the center of the district and also the town of Abuna Gindeberet whereas Gitire Kichu and Degatina are found at 3km and 15km respectively.

The district has 19,713 male and 2,913 female householders. The district is categorized into 2 agro climatic zones, where mid highland and lowland accounts to 32% and 68% consecutively. The district receives an average annual rainfall that ranges from 700mm in the lowland to 1400mm in the highland, with an average temperature that ranges from 10°c minimum to 30°c maximum. The land use system of the district shows that 87,784.25 hectare is cultivable land, about 36,726 hectare forest and bush, while 12,026 hectare land constitutes grazing land and finally, about 1,947 hectare covers the remaining area. The safe water coverage constitutes 36%.

Major soils of the area are vertisols consisting of 46% clay, 40% silt, 8% sand and 6% organic matter. The livestock population is estimated to be 145,974 heads of cattle, 34,660 heads of sheep and 40,688 heads of goats, 5,634 horse, 12,124 donkey, 969 mule, and 71,133 avians in Abuna Gindeberet district. In the study area, ruminants are managed by communal holding of all species such as cattle, sheep, goats and equines together [12].

Study design and study animals

A cross-sectional study design was implemented from March, 2018 to November, 2018 to determine the species and prevalence of ixodid tick infestation and associated effect in bovines in Abuna Gindeberet district. The study population consists of cattle managed under extensive and semi intensive system.

Sample size determination: The sample size was determined by assuming the expected prevalence of 50% tick infestation. The desired sample for the study was calculated by setting 95% confidence interval at 5% absolute precision [13].

N=1.962 Pexp (1-pexp) d2

Where, n= required sample

Pexp= expected prevalence

d2= absolute precision

Therefore, 384 cattle were examined under the study.

Sampling method: Simple random sampling was applied for tick collection from 384 cattle found within 3 Peasant Associations (PAs) of the Abuna Gindeberet district. The PAs were selected based on their accessibility to transport and information from the Districts manager. The animals were selected and examined randomly from the household.

Study methods: The host related factors like age and body condition were classified into groups for the convenience of the study. The age of the cattle were grouped into young (< 3 year), adult (3 to 7 years) and old (> 8 years) according to (Gatenby, 1991). While body condition score were grouped into poor, medium and good according to (Nicholson and Butterworth, 1986).

Tick collection and preservation: The entire body surface of the animals was inspected for the presence or absence of ticks. Adult ticks were collected from different parts of body regions; dewlap, udder, groin, shoulders, belly, flank, perineum, under tail, scrotum, teat, prepuce, thigh and sternum of animals after being restrained using physical handling. Date of collections, address, sites of attachment, breed, age, sex, body condition score and management system of animals were registered.

Ticks were removed from the host skin whilst retaining their good condition for identification using hand manually (Wendewossen, 2000). The collected ticks from each body regions were preserved in separate pre-filled universal bottles with 70 % ethyl alcohol before transportation to parasitological laboratory for identification.

Laboratory techniques for tick identification: From the bottle containing sample, the ticks were transferred to the petri dish by using forceps. The petri dish containing tick sample was placed under stereomicroscope. The collected ticks were identified and classified to different species levels based on size of mouthparts, color of the body, leg color, presence and absence of the eye. Furthermore, different morphology tick such as shape of scutum, body, coxae one, festoon and ventral plates were considered for species level identification [7].

Data analysis

The data recorded was entered into Microsoft excel data base system for statistical analysis. Stata version 11 statistical software was used to analyse the data. The association between tick infestation rate and study factors (such as age, sex, management system, body condition etc) was determined by pearson’s chi-square (x2) test. A statically significant association between variables exists when P‹0.05 and at 95% Confidence Level (CI). The prevalence of tick infestation was calculated as the number of positive animals for specific tick species sampled divided by the total number of animals examined and multiplied by hundred.

Results

The prevalence of ticks from the total examined cattle was found 71.35% (274/384). Among these 306 were local out of which 215 (55.98%) were infested and 78 were cross breeds out of which 59 (15.37%) were infested. A total of 412 adult Ixodidae ticks were collected from different body region of infested cattle. From which, four Ixodidae tick species were identified from the study area. Those identified species are; Rhipecephalus (Boophilus) decoloratus (65.77%) was the most abundant and widely distributed species followed by Amblyomma variegatums (28.30%) and Rhipicephallus evertsi evertsi (3.39%). However, Hyalomma dromedari (2.42%) was found to be the least abundant tick species (Table 1).