A cross-sectional study design was conducted; starting from December to April 2013 for five months in Debre Birhan districts, North Showa zone, Amhara Region Central Ethiopia, to assess the risk factors associated with infestation of the disease and Prevalence of ovine Fasciolosis. Simple random sampling was employed for the questionnaire survey and sheep selected. For questionnaire survey 102 households were chosen by Yamane, 1967 formula, for coprological 322 animals were sampled by Thru-field, 2005 formula. The data collected by face to face interview and the fecal sample collected direct from the rectum and adult fluke parasite collected from the liver via its duct. The data was managed by descriptive statistics of SPSS and the strength of associations of predictor to the outcome variable was analyzed using χ2 test and odds ratio (OR). The overall result, 79.4% of farmers were a graze their animal in both marshy and drought area. The source of water for the majority of small holder farmers 41.2% was open well. Prevalence of ovine Fasciolosis was 51.2% and 63.4% found by faecal and postmortem examination respectively. The overall prevalence of snail species in different habitats was that 42.7% in swamp grazing area, 36.4% in water bodies and 20.9% in muddy area. Lymnaea truncatula species were widespread than Lymnaea natalensis species in Debre Birhan districts because of Lymnaea truncatula species prefers highland agro-ecological.

• Fasciolosis

• Sheep

• Fasciola species

• Anthelmintics resistance

• Intermediate host

Zebene T (2023) Asses Risk Factors Associated with Ovine Fasciolosis, Identification Fasciola and Snail Species in Debre Birhan District, North Shawo Zone, and Amhara Region Central Ethiopia. J Vet Med Res 10(3): 1253.

Background and Justifications

Ethiopia has been a large number of livestock populations in Africa, its accounting 59.5 million cattle, 30.70 million sheep, and 30.20 million goats. Ethiopia has the largest numbers of small ruminant population in Africa [1]. In Ethiopia sheep are the most important small ruminant next to large ruminant [2]. They are important protein sources in the diets of the poor and help to provide extra income and support survival for many farmers in the tropics and sub-tropical areas [3]. Small ruminant has a significant role to maintain the household food security and economic strength to providing meat, milk, skin, wool and generate cash income by selling its products [4]. Sheep and goats have a unique role in small holder agriculture as they require small investments, faster growth rates, have shorter production cycles, and greater environmental adaptability as compared large ruminants [3]. Regardless of, the larger number of livestock populations in Ethiopia, its performance and involvement of the national economics has been comparatively low as a result of infestation of parasitic diseases, inappropriate health care and poor management systems [4]. The parasitic diseases have been among the ruminant animal constraint so as to the obstruction of productivity and reproductively performance of sheep, in many tropical countries [4].

The highland of the Ethiopia has been water logging marshy area and it provides suitable for habitat of the snail, which was intermediate hosts of Fasciola SPP [2]. The epidemiological occurrence of the Fasciola SPP are associated with water logging and swampy grazing area fields known the ideal used for the dissemination as well as maintenance of the intermediate host, which was the snail SPP [2]. Additional, in Ethiopia rational prophylactic program has sound Fasciolosis control strategically programs is needed based on local epidemiological information the parasite disease [5]. Epidemiology of the parasite infestation with respect to the time of rainfall, temperature area, humidity condition, favorable altitude and marsh area is very important in planning the control programs and also estimating the economic burden to the country due to the parasite infestation [6]. Apparently, losses by infestation parasitic diseases including Fasciolosis is predictable to be highly in temperate area such as Ethiopia was strategic and the most effective disease control strategic program is missing [6]. Epidemiology of the parasite infestation and prevalence of 50.8% ovine Fasciola has been reported by coprological study at Debre Birhan research center [7]. Also the prevalence of ovine Fasciolosis has been reported 24.4% at Haromaya municipal abattoir [8]. Similarly the incidence of ovine Fasciolosis was 32.6%, 70.2% and 49% have been reported at Addis Ababa abattoir [9], in North Showa, at Menz Lalo [10], in Dawa-Cheffa, at Kemissie [5], respectively. Fasciola causes significantly decreasing sheep productivity and reproductively and also economic loss due to the cost of flukicides for the controlling of ovine Fasciolosis [11]. Virtually, flukicides may differ in chemical structure, mode of action and also the efficacy drug against different developmental stages of liver fluke [11,12]. The anthelmintic drugs which used for treatment against liver fluke infection are triclabendazole, albendazole, tetraclozan and benzimidazoles [13]. Triclabendazole is a drug of choice for the treatment of ovine Fasciola, it was effectively treated both immature and mature liver flukes from the age of 2 days and albendazole is effectively treated only against mature flukes from 12 weeks onwards and a short withdrawal period for milk 60 hr. [12]. Therefore, form the above reason, this research thesis was initiated that the aim to assess the epidemiological occurrence with associated risk factors ovine Fasciolosis, identification of the predominate species of Fasciola as well as the snail species in small holder farmers in the study area of Debre Birhan selected districts.

Description of the Area

This study was conducted selected sites of the study area in Debre Birhan districts, it located at central high land of Ethiopia, in North Showa Zone, at Amhara Regional State and situated at distance of 125Km Northeast Addis Ababa, Ethiopia lying between 9°41’-9.683° N latitude and 39°32’-39°.533° E longitude and an elevation of 2,840 m.a.s.l [14]. The rainfall pattern in the study area was bimodal. The mean annual rainfall was 927.10mm Hg and its rainfall pattern is characterized by the maximum 1293.02mm Hg in August as well as the minimum 4.72mm in December. Similarly, monthly the maximum temperature the area was 18.6 °C and minimum temperature of 8.20 OC. The total land coverage is 18,081.95Km2 . The climate condition of the area was characterized by two seasons namely the summer /wet/ season from June to September and winter /dry/ season from October to May. The farming system in the study area is mixed agricultural system characterized by crop and livestock rearing. The location map of Debre Birhan town administrative and project site [15] (Figure 1).

Figure 1: Map Debre Birhan town at North Showa Zone in Amhara administrative Region.

Study Population

An estimated 20,200 sheep was reared around the study area in Debre Birhan districts in North Showa Zone Amhara administrative Regional State [16]. The study area was consisting nine kebele. The study animal comprised different breeds indigenous breed “Menze”, cross breed “Menze with Awassi” and “Awassi “breed, indigenous breed (“Menze”) cross breed as well as Awassi breed, and also different age, sex, body conditions groups and category found under the extensive free grazing system in the study area [15].

Study Design

A cross-sectional study design has been employed from November to May 2013 for four months in Debre Birhan districts. From three kebele 102 household were selected by simple random sampling strategy. The study was conducted assess risk factors associated with ovine Fasciolosis by using questionnaire survey, determine the prevalence of ovine Fasciolosis through faecal and postmortem examination, identification predominate Fasciola species via postmortem inspection, and to identify the species of snails based on field survey in and around selected districts. Data was gathered interviewing farmers and animal health experts at their respective areas. Animal level the data consists the age, sex, body condition scores, management system, number of sheep at risk, number of case and death was recorded, for coprological study the faecal sample was collecting from the rectum of each sheep and the snail sample was collecting from the field.

Sampling Strategy/Technique

Simple random sampling was conducted in selected households and kebeles. A total numbers of kebeles around Debre Birhan districts were nine. A total numbers of household that rearing sheep in nine kebeles were 1425. Three kebeles were selected from nine kebeles by simple random sampling. Similarly, from three kebeles 102 small holder farmers were selected by simple random sampling. Study populations (sheep) were selected from each small holder farmers by simple random sampling. Sampling units (sheep) were assigned proportionally to each kebele depending on the total population in each kebele.

Sample Size Determination

The total numbers of small holder farmers were included in the study determined depending the formula given by [17]. it has been provide a simplified to calculate as:-

n = N/1+ N (e) 2

Where: n = sample size, N= total number of targeted population, e = the error term of the precision level, which was 5% used for the standard error and at 95% confidence level.

n = 137/1+137(0.05) 2 = 102

A total of 102 small holder farmers were involved in the present study. According to kebele livestock extension workers documentations a total of 1425 small holder farmers were rearing sheep in nine kebeles, 432 small holder farmers were rearing sheep in selected three kebeles from their 137 small holder farmers selected which has rearing only sheep in each kebeles 47 in 01(Atakilt) 35 in 08 (Zangira) and 55 in 09 (Fagi).

The required sample size was determined by using stratified sampled formula adopted [18]. Taking 1.96 as multiplier for 95% CL, 70.2% predictable prevalence, at 5% absolute precision into consideration:-

Whereas: - n= total sample size; z = 1.96; p = predictable prevalence; d= absolute precision value. Therefore, it substituting the values into the above formula yields:-

A total of 322 heads of sheep have been examined. The sheep were proportionally allocated in three 50% (161) heads of sheep kebele 01(Atakilt); 16% (52) heads of sheep kebele 08 (Zangira) and 34% (109) heads of sheep kebele 09 (Fagi).

Questionnaire survey

A structured and organized questionnaire was prepared and administered to obtain the data on ovine Fasciolosis. The questionnaire was pre-framed in such a way that farmers have been provided the information which was recent and easy to recall, and it was filled directly by interviewing face-to-face. Household data include information about the age, sex, breed and body condition of the sheep, watering and feeding system, seasonality of the disease, and number of diseased and dead animals and frequently dewormed against Fasciolosis disease. Fecal sample collected

Fresh faecal samples were collected directly the rectum of sheep and kept in universal bottle containing 10% formalin and labeled sample code and without delay placed in cold box with ice, transported into Veterinary Parasitology Laboratory, stored in a refrigerator at 4°C if it has been processed more than two days kept at room temperature. Fasciola egg was identified by sedimentation technique [19]. Three grams of faecas was added into 42 ml of water in a graduated cylinder and mixed thoroughly using a glass rod, and it poured through a tea strainer, due to remove large debris. After that two drop of methylene blue was added and a drop of sediment was placed on slide covered with a cover slip and then viewed on by using compound microscope and detected presence or absence of Fasciola eggs.

Postmortem Examination

Postmortem examination was conducted to compare the prevalence of ovine Fasciolosis and to identify the species of Fasciola based on its morphology, which species of Fasciola is more pre-dominate Debre Birhan district. A total of 322 livers of slaughtered sheep were selected from Debre Birhan municipal abattoir by using simple random sampling and examined each liver to find out the liver flukes in the liver parenchyma and gall bladder.

Snail Collection and Identification

The snails were carried out in the morning when environmental temperature relatively low humidity was available suitable for snail survival. The potential habitat of snails was visited including edges of springs, irrigation canal, swamps and dam areas. Snails were identified morphologically using field guide to African freshwater snails [20]. Identification of the snail species by its morphology L. natalensis was longer in length, larger in width, high spire, and small aperture [14]. Also the surface of the spiral rows was small transverse grooves and lack strong spiral ridges of periostracum. L. truncatula was small in length, short in width, small the spire, high the aperture and strongly convex whorls.

Dataset Management and Analysis

All data have been analyzed with a statistical computer package for social sciences (SPSS) version 23 software. Descriptive statistic used to analyzed questionnaire survey, coprological laboratory findings, and strength of associations of predictor outcome variable was analyzed using χ2 test and odds ratio. The significant differences when P-value was ?0.05 at 95% CL.

Coprological Examination

From 322 sheep a fecal sample was collected and examined, from their 165 sheep have been positive for Fasciola. In general the prevalence of ovine Fasciolosis was 51.2% in the study area. The highest prevalence was recorded in local breeds 56.9%; n=132 while the lowest in exotic breed 33.3%; n=4, the difference was significant (p=0.005), also highest prevalence 90.8% in poor; n=79, whereas the lowest 28.3%; n=13 in good body condition, the difference was significant (p=0.000). It was also apparent adult sheep were more infected (53.6%) than young and similarly female sheep were more infected (55.3%) than males, the difference was non-significant.

Prevalence & risk factors of ovine Fasciolosis based on coprological examination: In this finding, the prevalence of ovine Fasciola was 51.2% based on coprological examined, and agrees with the previous study, 52.3% reported by [21], and 62.7% reported by [22], in the same area, but lower than 70.2% reported [10], in Manze Lalo. The variation in the prevalence due to seasonality, difference management practices, and diagnosis of Fasciola was very difficult because of the patent period was intermittent [22].

In this finding, the prevalence was 56.9% (n=132), in local 37.2% (n=29 in cross and 33.3% (n=4) in exotic breeds. The significant difference among breeds (P=0.005). This result was agreed with the previous study 54.2% in local, 32.1% in cross breeds [22]. Variation and significant difference among breeds was genetic effect and immune reaction [23]. Similarly, the prevalence of ovine Fasciolosis was 90.8% (n=79) in poor, 38.6% (n=73) in medium and 28.3% (n=13) in good body conditions. There was significant difference among body condition scores (P=0.000). The variation and significant difference among different body condition might be because of immunological reaction is better in sheep with good body condition score (Table 1).

Postmortem Examination

A total numbers 322 liver of sheep were examined, from their 204 liver affected by Fasciola lesions. Overall Fasciola lesion was 63.4%. Predominate species was F. hepatica with 47.8% Table5). Current finding, predominant species was F. hepatica (75.5%) followed mixed infection (15.2%) and 9.3% F. gigantica. [22]) reported predominant species was F. hepatica (68.8%) followed by F. gigantica (25.6%) and mixed infection (5.6%) in Debre Birhan municipal abattoir. The reason the difference was the distribution of Fasciola closely related with intermediate host the snail where L. truncatula prefers highland and amphibious while L. natalensis prefers low land (Table 2).

Prevalence & risk factors of ovine Fasciolosis based on postmortem examination: This results compare from previous, 70.2% was reported by [21], and 52.6% reported by [22], in Debre Birhan municipal abattoir. Lower prevalence 23.35% was reported by [4]. in Adwa municipal abattoir. Prevalence ovine Fasciolosis was different because of seasonal variation and associated risk factors. According to [21], reported occurrence of Fasciolosis was high in wet and rainy seasons, due to intermediate host more abundant.

The prevalence was higher in local (69.4%) breeds, and statistical significant (P=0.000). This result agrees with [22], was reported 54.2% in local, 32% in cross breeds. Also female was more affected (81.3%) than male sheep (51.9%) and difference was (P=0.000. Poor body condition was most affected (90.9%) than medium (67.6%) and good body condition (32.1%). This result agree with [22], was reported 61% in poor body condition, 46.5% in medium body conditioned and 37.5 % in good body conditions in Debre Birhan municipal abattoir [5]. Reported 73.7% in poor and 38.5% in good body condition was in Dawa Chefa municipal abattoir. Therefore, the difference was statistical significantly (p=0.000), due to this fact, cross breed sheep and poor body conditioned sheep has been lower immunity than medium and good body conditioned and also genetic effect and immune reaction. In addition to most of the time those sheep does not recommend for slaughtered (Table 3).

Questioner Survey

A minimum number of 102 small holder farmers were interviewed; from their 91.2% involved in mixed production system and 8.8% involved only livestock production system. Majority of the farmers (79.4%) were graze their sheep in both marshy and drought area. Also (41.2%) of the farmers were the source of water for drinking their sheep in open well followed by open well/stagnant water.

The production, the availability of feed and water system: The questionnaire survey indicated that the sheep were high exposed to Fasciola infections, because of the risk factors that associated with the infection of the disease, the difference was significant difference (p<0.05 in the study area. The survey showed that 79.4% of the farmers were grazing their sheep in both marshy and drought area, and the difference was statistical significant (p=0.000). Also 41.2% of the farmers were drinking their sheep in both open-well and stagnant water, there was statistical significant difference (p=0.000). From this research result the associated risk factors as well as the infection of the disease highly significant difference (p<0.05 in the study area (Table 4).

The questioner survey showed that, majorities 83.3% of the respondent did not know about snail as intermediate host for Fasciola. Apparently, 92.2 % of small holder farmers mentioned that snails are found in water body. Actually, 98% of the respondent farmers did not use snail control methods.

The distribution, location and control method of intermediate host snails: The result showed that, 83.3% of small holder farmers were not known the intermediary host the snail, but 16.7% of farmers were known the intermediary host the snail, there was statistical significant difference (p=0.001). Among them 92.2% of the farmers were know the location of the snail in water body but 2% of farmers in grazing area. Due to this fact, the occurrence of Fasciolosis was very high. The disease was endemic in the study area because of the risk factors which are associated the infection such as favorable temperature and climatic conditions, marshy and muddy grazing area, stagnant and open well water source favorable for the growth and development of intermediate host [23]. This research finding was approved [21], report most of the time the prevalence was high in wet and rainy seasons because of the intermediate hosts have been more abundance in the study area (Table 5).

The distribution, the location and the Habitat of intermediary host the snail species: A total 110 snail samples were collected from which 47 snails from grazing areas, 40 snails from water bodies, and 23 snails from muddy areas. Prevalence of snail species in different habitats was that 42.7% in swamp grazing area, 36.4% in water bodies and 20.9% in muddy area.

Occurrence of snail species in swamp grazing was 45.7% L. natalensis and 27.8% L. truncatula, in water body 33.7% L. natalensis and 50% L. truncatula and also in muddy area 20.7% L. natalensis and 22.2% L. truncatula, the reason variation is that L. truncatula prefers highland agro-ecological than other species of snail. Virtually, L. truncatula was the abundant snail species encountered in the study area, duo to L. truncatula prefers highland agro-ecological zone favorable for the survival of the intermediate host [24,25] (Table 6).

Generally this finding showed that incidence of ovine Fasciolosis was highly occurred and endemic disease in Debre Birhan district because of the existence of different associated risk factor of the disease. Along with the questionnaire survey result, it was evident that small holder farmers were not control the intermediate host the snails and the utilize anthelmintics drug was not properly and strategically. The overall result showed that, prevalence of ovine Fasciolosis was 51.2% and 63.4%, by coprological and postmortem examined respectively. This study revealed that higher prevalence of ovine Fasciolosis was recorded in postmortem than coprological, the reason that postmortem was a golden standard. According to this study finding showed that, the geographically allocation of the intermediate host the snails species were most abundant in marsh grazing area, irrigated water bodies, and muddling area in decreasing order. Lymnaea truncatula was highly prevalent than Lymnaea natalensis in the study area, because Lymnaea truncatula prefers highland agro-ecological zone.

Recommendation

To prevent and control ovine Fasciolosis the method was drainage of marshy grazing areas as well as stagnant water bodies, improving the management systems such as especially grazing, housing and watering system, and use mulluscicidal this method was important to eliminate the intermediate host the snail populations Strategic deworming to prevent pasture contamination and eliminate adult flukes such as at August/ September from autumn and winter and at January/ February: during late spring and early summer.

North Showa zone livestock office as well as Debre Birhan livestock department was implements strategic planning and extension activities for the prevention and control of ovine Fasciolosis.

This study was dealing about to assess the associated risk factor ovine Fasciolosis, epidemiological occurrence of Fasciola species, the distribution of the intermediate host and anthelmintics resistance of ovine Fasciola in the study area at Debre Birhan district.

I would like to express my deepest thanks to God for allowing me permission to do all daily activities, Dr. Mussie Hailemelekot; Dr. Kassa Demssie and Dr. Wedajo Muleta for their advice, encouragement starting from proposal development and until my thesis writing up.

I would like to acknowledge Bahir Dar University, from the beginning to give a free education sponsorship to my post graduate study with the agreement of Amhara Region Bureau of Civil Service, and the study was financially supported.

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