Epidemiological study on Gastrointestinal Helminths of horses in Arsi-Bale highlands of Oromiya Region, Ethiopia

A study to determine the prevalence and associated risk factors of gastrointestinal helminths in horses was conducted from October 2009 to May 2010 in three districts of the Arsi-Bale highlands of Oromiya region. A total of 2683 fecal samples for the coproscopic examination and 80 pooled samples for recovery of parasitic larvae were collected and processed in Asela Regional Veterinary Laboratory. The overall prevalence of gastrointestinal helminths was 84.4 %, out of which, 59.1 % were mixed infections. Coprological examination revealed the existence of six species and five genera of helminths namely, Strongylus species 39.5 %, Cyathostomes 35.1 %, Trichostrongylus axei 29.0 %, Fasciola hepatica 23.1 %, Triodonthophorus species 13.9%, Parascaris equorum 11.7 %, Oxyuris equi 1.8 %, Strongyloides westeri 0.7 %, Dictyocaulus arnifieldi 0.5 %, Anoplocephala species 0.3 % and Gastrodiscus species 0.2 %. No significant variations (P>0.05) in prevalence of helminths were noticed in relation to districts, age and sex groups of horses, except in case of Parascaris equorum and Fasciola hepatica, in which prevalence was observed to significantly decrease and increase with age, respectively (P<0.05). The average egg per gram of faeces in this study was 745.2 with a range of 100 to 10,500. The coproculture study revealed that Strongylus vulgaris, Strongylus edentatus and Cyathostomes were the major helminths larvae identified in the area during the study period. Thus, the present study revealed that gastrointestinal helminths are among the major health constrains of equines in the area demanding an urgent control intervention.Keywords: Epidemiology, GI helminths, Horses, Ethiopia, Arsi-Bale, Oromyia

Experimental infection of Ethiopian highland sheep by different infective doses of Haemonchus contortus (L3): haematological and parasitological parameters, serum protein concentrations and clinical responses

The study was conducted to examine changes in haematological and their eventual associations with parasitological parameters and clinical responses in experimentally infected Ethiopian highland sheep by increased doses of Haemonchus contortus infective larvae (L3). A total of 24 male sheep were allotted in to four equal groups: a single dose of 2 000, 4 000, or 6 000 infective larvae of Haemonchus contortus (L3) was orally administered to animals from the first 3 groups whereas the last group not treated and served as negative control. The faecal egg count (EPG), the body weight as well as haematological parameters (haematocrit and eosinophils counts) and proteinaemia were measured throughout the experimental 13 weeks long period and worm burden and sex ratio were assessed at necropsy. The infection was confirmed by the occurrence of the faecal egg excretion and by the presence of adult worms in abomasums. All Haemonchus infected sheep exhibited a progressive and severe anaemia characterized by marked reductions of haemoglobin concentration and haematocrit, associated with weight loss and growth retardation and on the contrary with strongly and transiently increased eosinophil population compared to control animals (P<0.01). Except for proteinemia, parasitological, clinical and haematological alterations were significantly proportional to the parasite load. Moreover, the eosinophil counts, the adult worm population and the egg excretion positively and significantly correlated together, whereas they were negatively associated with body weight, proteinemia and the other haematological parameters. All experimentally infected animals appeared to be highly susceptible to the infection by Haemonchus contortus and the severity of the haemonchosis was clearly related to the infective dose

Impact of sheep and goats ectoparasites on the tanning industry in Tigray Region, Ethiopia

A study was carried out to assess the effect of ectoparasites on the quality of processed skin and defects that cause downgrading and rejection of skins in pickled sheep and wet blue goat-skins at Wukro Sheba tannery in Tigray region. A total of 120 sheep and 120 goat pelts with known infestation by ectoparasites and ectoparasite free control pelts were purchased and processed in Sheba tannery and the corresponding skin defects were analyzed. Accordingly, three groups of 40 sheep pelts each (one group infested with M. ovinus, one group infested with Damalina ovis and a control group of ectoparasite free sheep pelts) and three groups of 40 goat pelts each (one group infested with sarcoptic mange, one group infested with Linognathus spp. and a control group of ectoparasite free goat pelts) were used. Defects observed at pickled stage include cockle, scratch, scar, technical defects due to flaying and old age. A strong association (P<0.001) was observed between cockle lesion and infestation of sheep pelts with D. ovis and Mellophagus ovinus and infestation of goat pelts with sarcoptic mange. Further more, the severity of infestation of sheep pelts with M. ovinus and D. ovis and infestation of goat pelts with sarcoptic mange were found to correlate significantly (P<0.001) with severity of cockle defect. Further investigation on 1000 pickled sheep and 1000 wet blue goat skins revealed that scratch defect was the dominant (43.4 % and 53 %), followed by cockle (35 % and 21.5 %), scar (7 % and 6.8 %) and knife cut (3.4 % and 6.2 %) in pickled sheep and wet blue goat skins, respectively. There was a significant difference (P<0.001) in proportion of cockle between pickled sheep and wet blue goat skins. In addition, a strong association (P<0.001) was observed between cockle and scratch, and cockle and scars on both pickled skins. The economic loss due to quality deterioration of exported skin in the study tannery was estimated to be 778,199.41 USD for pickled sheep and 247,677.61 USD for wet blue goat skins per annum. The growing threat of ectoparasites to small ruminant production and to the tanning industry needs well coordinated and urgent control intervention.Keywords: Ectoparasites, Goat, Sheep, Skin defects, Tigray Region, Ethiopia

Ectoparasites of Sheep and Goats in North-West Amhara Regional State, Ethiopia

A cross-sectional study on ectoparasites of sheep (n=738) and goats (n=492) was conducted in Northwestern Amhara Regional State of Ethiopia from October 2009 to April 2010 to determine the prevalence of major ectoparasites of sheep and goats and the associated risk factors. Out of the clinically examined animals, 331(44.9%) sheep and 214 (43.5%) goats were infested with one or more ectoparasites. Ectoparasites identified in sheep were Damalinia ovis (30.9%), Mellophagus ovinus (10.8%), ticks (3.9%), Linognathus species (3.1%) and flea (1.1%). Among goats, Linognathus species, ticks, flea and demodectic mange were identified with respective prevalence of 27%, 17.7%, 2.6% and 2.2%. Sheep in midland were 3.7 and 2.3 times more at risk for Damalinia ovis infestation than sheep in highland and lowland, respectively and also goats in midland were 1.8 times at risk for Linognathus species than lowland sheep (P < 0.05). Sheep poor in body condition were 1.9 times more at risk for Damalinia ovis than good body condition sheep and goats poor in body condition were 3.5 times more at risk for Linognathus species than good body condition goats (P< 0.05). Age and wool length of sheep were important predictors for the presences of Mellophagus ovinus on highland sheep. The prevalence of Mellophagus ovinus was significantly higher in young and long wool sheep than in adult and short wool sheep (P < 0.05). The observed overall prevalence is generally high which may result in enormous economic losses through decreased production and productivity, damages to the skin and deaths of the animal which requires an immediate attention and professional intervention.Key words: Ectoparasites, Ethiopia, Goat, Prevalence, Risk factors, Sheep

Field investigation of anthelmintic efficacy and risk factors for anthelmintic drug resistance in sheep at Bedelle District of Oromia Region, Ethiopia

The study was conducted to investigate the status of anthelmintic (AH) efficacy and associated risk factors for AH resistance in sheep. Questionnaire surveys were undertaken to establish the AH utilization practices of sheep owners at the study area and identify risk factors. Four hundred fourteen sheep were sampled of which 180 sheep were selected based on their higher egg count for the fecal egg count reduction test (FECRT) to assess the efficacy of albendazole, tetramisole and ivermectin against gastrointestinal nematode parasites prevailing in sheep. Fecal culture and postmortem examination techniques were used to identify the species of nematode parasites prevalent before and after treatment. The results show that: 1) albendazole and tetramisole were the most frequently used AH in the area, 2) farmers get the drugs with or without prescription from various sources (10% open markets, 18% private drug stores and 72% government animal health clinics and 3) the prevalence of gastro-intestinal nematode infection in the study areas was 72%. 4) The FECRT revealed all the three tested AH were effective with egg count reduction levels of 96%, 99% and 97% respectively for albendazole, tetramisole and ivermectin. However, post-treatment fecal cultures and postmortem adult worm recovery showed that some Haemonchus contortus worms have escaped the treatments. In conclusion, no anthelmintic resistance was detected from clinical cure point of view but the population of H. contortus that has escaped the treatments deserves further scrutiny as this parasite is the most prolific and highly pathogenic in sheep.Key words: Anthelmintic efficacy, FECRT, Gastrointestinal Nematodes, Risk Factors, Sheep

Epidemiology and economic importance of fasciolosis of domestic ruminants in selected districts of Tigray Region, Ethiopia

An epidemiological study on fasciolosis of domestic ruminants was conducted in four Districts of Tigray Regional State to determine prevalence, identify Fasciola species, assess risk factors and evaluate economic loss. A total of 1708 domestic ruminants were sampled for coprological investigation; in addition 236  slaughtered ruminants were examined at post mortem. The overall prevalence of  fasciolosis in domestic ruminants was 21.2% (95% CI: 15.8-26.9%) and 32.6% (95% CI: 29.7–35.6%) based on coprology and post mortem examinations, respectively. The prevalence in cattle, sheep and goats was 25.3%, 35.7% and 11.4% respectively, based on coprology. The highest prevalence was recorded in Ofla District (41.9%) and the lowest in Alamata District (10.8%). The prevalence was higher in the highland (67.9%) than the midland (17.4%) and the lowland (14.4%); aged animals, and in poor than good body condition in all species. The  prevalence of F. hepatica was 73.1% and 62.7%, and F. gigantica 26.9% and 37.3% by egg and fluke examination, respectively. Statistically significant difference was observed in prevalence among districts, animal agro-ecology, age, and Fasciola species (p<0.05); while no significant association was observed between sexes in animal species (p>0.05). The odd of having fasciolosis in the highland than the lowland was more than 4 times higher (OR= 4.77), similarly the risk in sheep compared with goats was higher by more than 4 times (OR=4.33). During the five years period, out of 11,966 inspected livers, 22.62% were condemned due to fasciolosis. The annual direct and indirect economic loss incurred due to fasciolosis in the study area was estimated to be 286,536.21 Ethiopian Birr (31837.36 USD). Out of the total losses 80.9% was from cattle. The present study revealed a high infection of domestic ruminants by Fasciola species especially in the highland resulting in huge economic losses, hence, intervention to mitigate fasciolosis is required.Keywords: Coprology, Fasciola spp, Risk factors, Post-mortem, Prevalence, Tigray Regio

Bovine cysticercosis and human taeniosis in South-west Shoa zone of Oromia Region, Ethiopia

A cross-sectional study was conducted in cattle slaughtered at Sebeta, Tulu Bolo and Weliso abattoirs in southwest shoa zone of Oromia region, Ethiopia to estimate the prevalence of bovine cystiercosis using routine meat inspection method, and questionnaire surveys were undertaken to assess the status of taeniosis and associated risk factors in human in these towns. Accordingly, out of 1216 carcasses examined, 4.6 % were found infected with Cysticercus bovis. Among the positive cases for C. bovis, 39.3 % were viable and 60.7% were non-viable cysts while it was more prevalent in the heart and tongue (39.3% and 30.4%, respectively) than in the diaphragm and liver. Out of 392 respondents, 55.1% had contracted T. saginata at least once in the past years. The prevalence was significantly higher in adults (> 20 years) than youngsters (< 20 years) (P<0.001), in male than females (P=0.046), in Christian than Muslim community (P=0.011), in butchers and abattoir workers than in other occupation (P<0.001), in illiterate than in literate and university graduates (P=0.001) and in raw meat consumers than in others (P<0.01. In conclusion, bovine cysticercosis caused by C. bovis and associated human taeniosis are important problems in the study areas. Improvement in meat inspection procedures and sanitary conditions in the study areas are needed.Key words: Cysticercosis, Cattle, Human, Taeniosis, Ethiopia

Comparative study on the pathogenic effects of Diminazine aceturate sensitive and resistant isolates of Trypanosoma congolense in goats

The study was conducted in goats to compare the pathogenic effects of Trypanosome congolense known to be resistant and sensitive to Diminazine aceturate at 7 mg/kg, respectively. Fifteen male goats, 6 to 10 months of age were randomly divided into three groups. The first group (Group A) was artificially infected via intravenous route with the Diminazine aceturate resistant T. congolense isolate while the second group (Group B) received Diminazine aceturate sensitive T. congolense isolate and the third group was left non- infected control (Group C). The goats were clinically monitored for 11 weeks and blood samples were collected three times a week for parasitological and hematological examinations. The mean body temperature was found to fluctuate between (37.2ºC±0.24 ºC and 39.0 ºC ±0.30 ºC 37.5ºC±0.10 ºC and 40.0ºC±0.48 ºC in groups A and B, respectively with statistically significant (p<0.05) differences. A mean parasitaemia score of 2.5±0.48 and 4.0±0.0.50 was recorded in groups A and B, respectively with significant variation (p<0.05). The mean packed cell volume was also varied between 27.0%±0.48% to 18.5%±0.36% and 26.0%±0.25% to 17.4%±0.0.47% in groups A and B, respectively with statistically significant (p<0.05) difference. A marked decline in mean packed cell volume and raise in parasitaemia was noticeable in group B as compared to group A. The difference in packed cell volume among the groups was statistically significant (p<0.05). In the control group, the mean body temperature and packed cell volume recorded was in the physiological range throughout the trial period. The present study disclosed that in spite of differences in the level of parasitaemia, anemia was found to be the prominent clinico-pathological finding in both Diminazine aceturate resistant and sensitive isolates of T. congolense infected goats