prevalence of gastro
TRANSCRIPT
Preliminary investigation of Prevalence of gastro-intestinal parasites of Mules in Udayapur District, Nepal
1:Dr.Kedar Karki. M.V.St.Preventive Veterinary Medicine.
2:Dr.Poornima Manandhar
Senior Veterinary Officer.
Central Veterinary Laboratory,
Tripureshwor,
Kathmandu Nepal,
Abstract
A study from June .2006 - Sept. 2006 was conducted in Udayapur district of Eastern Nepal to identify the gastrointestinal parasites of mules, determine their prevalence rates and find associations between the acute sudden death of mules with colic symptom and parasites burden.A total of 33 faecal samples were collected randomly for qualitative and quantitative faecal analysis. The parasites encountered were Strongyle (100%), Parascaris equorum (50%), Oxuris equi (3%) and Fasciola (1.5 81.7% of mules sampled were severely infected, 8.3% heavily, 3.8% moderately and 6.2% mildly infected. Mixed infections were detected in 54.8% of the mules.
Key words: Mule, Udayapur, gastrointestinal parasites, prevalence
Introduction
Despite the increase in mechanization throughout the world, Mules donkeys are still well deserving of the name 'beasts of burden'. They have a prominent position in the agricultural systems of many developing countries. This is shown by the wide spread use of donkeys in rural and urban areas in Africa (Pearson et al 1999). It is suggested that donkeys can play a great role in the frame works of food security and social equity of high food insecure countries. Nepal has 2001/02 Horses 2, 01000 Mules and asses 60 000. In areas away from roads,
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many Nepalese use mules or yaks to transport food and other supplies to villages. Groups of 20 or so mules form a mule train, which is driven by one or two people. Each mule can carry several hundred pounds on its back and walk for many miles each day (CBS2007-06-14).These mules are primarily used for domestic good transport in the track of high and mid mountain of Nepal where surface road transportation and air transport is not easily assessable.These animal not only provide the alternative entrepreneurship in these region but also provide alternate employment opportunity in this area.Same type of situation do prevail in other part of globe Ethiopia has about 7.9 million equines, where 5.2 millions are donkeys (CSA 1995). There is one equine for every four people in the agricultural sector and for every five persons of the total population (Wilson 1991).The Domestic donkey of Ethiopia traces its ancestry to the wild asses found in Egypt, the Sudan, Somalia and Ethiopia, namely Equus asinus africanus and Equus asinus somalicus (Feseha 1991). The low level of development of the road transport network and the rough terrain of the country make the donkey the most valuable, appropriate and affordable pack animals under the small holder farming system of Ethiopia (GebreWold et al 2004). Donkeys appear to be an effective entry point for assisting women not only in domestic responsibilities, but also enabling women to be engaged in income-generating activities which otherwise they may not have had access to (Marshall and Ali 2004). Abayneh et al (2002) has revealed that in areas where draft power is a constraint for crop cultivation a pair of well-conditioned donkeys could be used as an alternative draft power sources for secondary and tertiary land preparations. Most of the mules being used in Nepal they are being brought from nebouring part of India.Very few of them are natively breeded. Even though Mules donkeys have often been described as sturdy animals, they succumb to a variety of diseases and a number of other conditions. (Svendsen 1997).
The attention given by Governmental and non-Governmental organizations to donkeys has been far below to what it deserves. This might be partly due to the wrong perception that the donkey does not require a lot of care, that when donkeys do get sick they are quick to die, and the donkey's low traditional status (Marshall and Ali 2004). Despite the huge numbers and the increasing importance of donkeys in the Ethiopian economy, knowledge about the health problems affecting their welfare is limited for most parts of the country.
Statement of problem:
The District Livestock Service Office Udayapur reported the periodic death of total 31 adult mules during June .2006 - Sept. 2006.With sowing symptoms like Abnormal behavior, aggression, changing
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habits, Abnormal proprioceptive positioning, Abnormal pupillary response to light, Agalactia, Anorexia, Ataxia, Blindness, Circling, Colic, Coma, Cyanosis, Decreased amount of stools, absent feces, constipation, Decreased borborygmi, Decreased, absent thirst, hypodipsia, adipsia, Dehydration, Difficulty in prehending or chewing food, Disoriented, Dullness, Dysmetria, Dysphagia, Dyspnea, Excessive salivation, Excitement, Generalized weakness, Head pressing, Head shaking, , Head, face, ears, jaw weakness, droop, Head, face, ears, jaw, nose, nasal, swelling, Head, face, neck, tongue hypoesthesia, Hemoglobinuria or myoglobinuria, Hyperesthesia, Icterus, Inability to stand, Increased respiratory rate, Mydriasis, Opisthotonus, Paraparesis, Petechiae or ecchymoses, Propulsion, Red or brown urine, Reluctant to move, Seizures or syncope, Skin edema, Sudden death, Sweating, Tetraparesis, Tongue weakness, Trembling, Tremor, Underweight, poor condition, thin, emaciated, unthriftiness, ill thrift, Weight loss.Death within 10-15 minutes after collapsing on the ground. These herd were being treated with antibiotics and vaccinated against anthrax during this period with unchecked mortality. On field investigation, obtaining a thorough history and completing a physical examination, it was discovered that the horses were being fed cracked and moldy corn,most of the mules in the flock were having poor body condition.These animals were not regularly dewormed against gastrointestinal parasites too.As the one of the symptom showen by these mule herd was colic probable cause might be deu to verminous colic was considered.
Review of literature:
The prevalence of Strongyle spp. was 100%. This is in harmony with the work of Yoseph et al (2001), Mulate (2005) and Fikru et al (2005) who have reported 100%, 100% and 98.2% in donkeys of Wonchi, high lands of Wollo province and western highlands of Oromia, respectively. Strongyle infestation was significantly higher (p<0.05) in the rainy season of the year. This was in accord with the work of Yoseph et al (2001), Mulate (2005) and Fikru et al (2005) who indicated that fecal worm egg counts begin to rise to severe levels during the wet season. This could be because of the long pre-patent period of the strongylus spp. which ensures that larvae acquired in one grazing (wet) season, only reach maturity during the next (Urquhart et al 2001). From this seasonal variation of strongyle infestation, treatment schedules that enable the elimination of the parasites at peak infection and prevent re-infection of pastures can be proposed. Troncy (1989) has proposed two treatment schedules per year with broad-spectrum anthelminthics for tropical conditions. A treatment may be given at the end of the rainy season. At this time, the animals are well nourished and may
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harbor large number parasites without being seriously affected. Eliminating these parasites will improve the adaptation of the animals to the harsh dry season conditions. Another treatment can be given at the end of the dry season. This treatment reduces infestation of pastures at the time of first rains and by residual parasites. Although the young had relative higher mean epg, there was no stastically significant difference (p>0.05) between age groups for the level of strongyle and Parascaris equorum infections. This might be the effect of mal-nutrition which reduces the host-parasite response and increased land of cultivation which restricts donkeys on small communal grazing land which allows the animals for continuous larvae exposure.
The prevalence of Parascaris equorum was 50%. This is in agreement with Mulate (2005) who reported 43.8% in south and north Wollo provinces. Yoseph et al (2001) and Fikru et al (2005) have reported 15.7% and 17.3%, respectively. These finding are relatively lower than the present finding. This could be because of the smaller sample size used in their study. Level of Parascaris equorum infestation had no significant difference for the different seasons of the year. This might be due to the high resistance of the eggs of Parascaris equorum to desiccation. Soulsby (1982) has stated that Parascaris equorum eggs are very resistant to adverse conditions, like drying or freezing and the larvae rarely hatch and infection usually takes place through ingestion of the eggs. Heavy infections of Parascaris equorum causes impaction and perforation leading to fatal peritonitis (Urquhart et al 1996).We confronted a case of a 15 years old female donkey that died of this complication.
Oxyuris equi with prevalence rate of 6% was very low compared with the work of Yoseph et al (2001) who reported 32.4%. The low prevalence in this study might be the effect of relative higher temperature in the present study area which desiccates the highly susceptible O. equi eggs.
Lower prevalence (1.5%) of Fasciola was recorded in the present study compared to other reports in the central highlands of Ethiopia (Yoseph et al 2001, Mulate 2005). This lower prevalence might be due to the differences in ecological conditions for the development of intermediate snails and the parasite. Hammami and Ayadi (1999) have reported that permanent dampness, suitable luminosity, basic pH of soil and water, and temperature contribute to the multiplicity of snails. The infections were recorded in April (from snail infection of Nov. - Dec.) and July (from snail infection of March-April). A study conducted by Hardy et al (2002) in Egypt indicated that donkeys are the potential reservoir of Fasciolosis and they recommended that donkeys should be
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considered within the preventive and control measures of Zoonotic Fasciolosis.
Cultural identification of larvae indicated 100% prevalence of Strongylus vulgaris and Cyathostomes. This is in agreement with the study of Yoseph et al (2001). S. vulgaris is the most pathogenic in Equines, causing unthriftiness, weakness, and increased susceptibility to other infection and even death and fatal colic could also have arisen from strongylid overload (Khallaayoune 1991). Dictyocaulus arnfieldi was recovered in 32% of the fecal cultures. Donkeys act as reservoir of Dictyocaulus arnfieldi and as a source of infection for horses (Beelitz et al1996).
The body condition score was negatively correlated (r= -0.67) with the total mean epg which implies that the body condition score is a good indicator of parasitic burden, which can be used by the resource limited communities to identify donkeys with immediate requirement of anthelmintic remedies.
The mean value of the haematocrit reading was slightly lower than that reported by Saul et al (1997). The variation in haematocrit may be due in part to the low altitude of Dugda Bora District. This variation could also be due to differences in parasitic burden (Egbe-nwiyi and Gana 2003). The packed cell volume was negatively correlated (r=-0.6) with total EPG. Egbe-nwiyi and Gana (2003) have reported that helminthosis in donkeys causes normocytic and normochromic anemia. This result might pave the way for the development of the FAMACHA© system for donkeys where eye color chart can be used as a diagnostic tool for heavy parasitic infections. The use of FAMACHA© system and employment of available potent anthelminitic remedies by poor farmers to treat animals identified with heavy infection appear sustainable and effective approaches to combat worm infection and maintain acceptable levels of goat production in poor farming regions of South Africa (Vatta et al 2003).
A large proportion of donkeys suffered various degrees of wounds. Pearson et al (2003) reported that the main sources of wounds were inappropriate harness, hobbles and saddle design, hyena bite, donkey bite, and car accident, injury by the owners or other people. Harness related problems were raised from incorrect size, inappropriate fitness, too narrow or too thin, made of unsuitable synthetic materials. Poor padding, poor design and synthetic rope to fix the load were the problems related with using pack saddles. Personal observations of the authors and history gathered from the donkey owners confirmed this report.
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Cases of Strangles were diagnosed in two young donkeys with signs of persistent bilateral nasal discharge, bilateral swellings in the regions of Viborg's triangle, enlarged retropharyngeal lymphnodes and increased temperature (Rose and Hodgson 2000). Other respiratory complications were increased respiratory rate, dyspnoea, mucoprulent nasal discharge, and coughing that might be symptoms of Bacterial pneumonia, pleuroneumionia, verminous pneumonia and chronic obstructive pulmonary disease (COPD) (Rose and Hodgson 2000).
Thrush, cracked heel, hoof abscess, hoof keratoma and hoof overgrowth were the hoof abnormalities confronted. Nails, thorns, and other sharp objects were removed from the sole-wall junction or white line of abscessed hooves. There is no regular hoof care of working donkeys in the area which exacerbated the problems. Feseha (1997) has reported that the predisposing factors for hoof problems of Ethiopian donkeys are related with poor hoof care and poorly drained yards where donkeys stand for lengthy period in mud. A case of mild tetanus was handled. This donkey had abscessed hoof which might be the route of entry and proliferation of clostridium tetani organisms (Blood et al 1983).
Sarcoids were observed in 3.1% of donkeys. Yilma et al (1990) has indicated that sarcoids are a common skin tumour in donkeys of central highlands of Ethiopia. The clinical appearances of sarcoids were fibroblastic, verucose, nodular and mixed types (Pascoe and Knottenbelt 1999).
Objectives of this study were
To determine spectrum of species and prevalence of major GIT parasites involved in donkeys.
To determine seasonal distribution of donkeys GIT parasites.
Materials and methods
Study area
The study was conducted during the year June .2006 - Sept. 2006 in Uadayapur District of Eastern Nepal .The long rainy season in the area is between June and October, while the long dry season lasts from October to February.
Study animals and protocol
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A total of 33 mules were randomly selected from 12 holdings of Mule transporters associations of Udayapur district and subjected to quantitative and qualitative coprological examinations to identify the major GIT parasites involved, to determine their prevalence rates.
Faecal samples were taken directly from the rectum or the ground when the animal was seen defecating with strict sanitation and placed in air and water tight sample vials, and then brought to the laboratory. Gross faecal examinations were done before the samples were subjected to microscopic examinations. Modified McMaster and Baerman techniques and sedimentation and floatation methods were used to identify and count eggs or larvae of parasitic helminthes (Urquhart et al 1996; Soulsby 1982). Faecal cultures were done for samples with total mean egg counts of greater than 10,000. Identification of larvae (L3) was based on specific morphological traits set by Poynter (1970). Levels of worm infection were extrapolated from infection severity index defined by Soulsby (1982) where horses are said to have mild, moderate, heavy and severe nematode infestation if their fecal egg counts are less than 500, 800-1000, 1100-1500 and more than 1500, respectively.
Data Analysis
Descriptive statistics were used to determine the prevalence of endoparasites and percentage of health problems in the area. Association of total eggs per gram with body condition score and packed cell volume was determined by Pearson test (SAS 1998). One-way ANOVA in a General Linear Model (GLM) (SAS 1998) was used to observe the variations of total epg of parasite species with age, seasons and sex groups. In all the analysis, confidence level was held at 95%.
Results
Microscopic fecal examination
All samples examined (n=338) were found positive for helminth eggs. Strongyle (100%), Parascaris equorum (50%), Anoplocephala Spp. (7.4%), Gastrodiscus aegypticus (6%), Oxuris equi (3%) and Fasciola (1.5%) eggs were identified. 81.7% of donkeys sampled were severely infected, 8.3% heavily, 3.8% moderately and 6.2% mildly. The highest faecal worm eggs count was recorded in the long rainy season (20143 epg) and the lowest worm egg count (50epg) was recorded in the long dry season.
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The statistical associations of total mean epg of GIT parasites with seasons and age groups are located in Tables 1 and 2, respectively. Body condition score was negatively correlated (r=-0.67) with epg counts. There was no statistically significant difference in level of helminth infection between male and female donkeys (p>0.05).
Table 1. Mean values (± SD) of epg in different seasons of the year for different parasites.
Strongyle5041±3726
Parascaris equorum
332±722
Cestode 36.6±149Oxuris equi 1.37±12Fasciola 2.05±14
Table 2. Mean values (± SD) of epg of parasites.
Helminth parasites Adu
lt
Strongyle
3973 ± 3153
Parascaris equorum
374 ± 791
Cestode7.42 ± 44
Oxuris equi
0.00
Fasciola1.37 ± 13
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Discussion
The microscopic fecal examination showed that helminthosis was an important health disease in the study area. Mixed infections were detected in 54.8% of the donkeys. Based on the severity index defined by Soulsby (1982), 81.7% of donkeys sampled were severely infected, 8.3% heavily infected, 3.8% moderately infected & 6.2% mildly infected. The maintenance of high infection rate of parasitic helminths in the study area might be associated with lack of any parasitic helminths intervention program and the management system in the area where many equines were allowed to graze together on small plots of land through out the year which facilitates contamination between animals. The prevalence of Strongyle spp. was 100%. This is in harmony with the work of Yoseph et al (2001), Mulate (2005) and Fikru et al (2005) in donkey who have reported 100%, 100% and 98.2% in donkeys of Wonchi, high lands of Wollo province and western highlands of Oromia, respectively. The prevalence of Parascaris equorum was 50%. This is in agreement with Mulate (2005). Lower prevalence (1.5%) of Fasciola was recorded in the present study compared to other reports in the central highlands of Ethiopia (Yoseph et al 2001, Mulate 2005). This lower prevalence might be due to the differences in ecological conditions for the development of intermediate snails and the parasite. Oxyuris equi with prevalence rate of 6% was very low compared with the work of Yoseph et al (2001) who reported 32.4%. The low prevalence in this study might be the effect of relative higher temperature in the present study area which desiccates the highly susceptible O. equi eggs. Finding of this study seems to be similar to the work of the researcher who had conducted a detail study on disease and parasitic condition of donkey (Ayele G, Feseha G, Bojia E and Joe A 2006) in African continent.
As this study was conducted while investigating the cause of acute sudden death syndrome with some colic symptoms this much work itself may not provide the true picture of parasitic problem of Equids but still provides some clue for new thinking toward the health problem of this valuable pack animals.
Conclusions and Recommendation:
Helminthes, and other health problems were identified affecting the health and welfare of mules in the study area.
Government or non profitable development agencies should include mules in their priority lists of research and develop
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sustainable integrated diseases prevention and control programs that are practical for developing communities.
Acknowledgment
We are grateful to the Mule transporters association for their cooperation in conducting this investigation study. We are also grateful to the Central Veterinary Laboratory staff and Mule owners of Udayapur district for their support and cooperation in the study period.
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