Seroepidemiology of Toxoplasma gondii in small ruminants in Northwest Ethiopia.

This cross-sectional study with a cluster random sampling method was undertaken from November 2018 to May 2019 to estimate the prevalence and assess the potential risk factors of T. gondii seropositivity, and to assess the association of the T. gondii seropositivity with reproductive losses in small ruminants in Northwest Ethiopia. A total of 576 blood samples from 135 small ruminant flocks were collected and assayed for T. gondii IgG antibodies using the Toxo-latex slide agglutination test. A questionnaire survey was also conducted to gather information on the potential risk factors of T. gondii seropositivity and on the status of reproductive losses in the small ruminant flocks. The study demonstrated a high flock and animal level T. gondii seroprevalence of 96.3% (95% CI: 91% - 98%) and 70.48% (95% CI: 68% - 79%), respectively. Mixed effect logistic regression analysis of the potential risk factors showed that the odds of seropositive for T. gondii was significantly higher in sheep (OR = 1.7, 95%CI: 1.19-2.46) than in goats, in adult (OR = 1.6, 95%, CI: 1.11-2.31) than in young, in the presence of cats (OR = 2, 95%CI:1.32-3.04) than in the absence of cats, in the lack of knowledge on the role of cats as a pathogen source than knowing it (OR = 1.82, 95% CI:1.21-2.77). The study also showed that the likelihoods of experiencing the abortion, neonatal death and weak birth in the previous one year in T. gondii seropositive flocks were 20.76 (95% CI: 2.2-195.1, p < 0.001), 8.90 (95% CI: 1.99-83.0, p = 0.021) and 9.33 (95% CI: 1.1-86.2, p = 0.019) times more than the seronegative flocks, respectively. In conclusion, this study revealed high flock and animal level seroprevalence of T. gondii in the small ruminant population in northwest Ethiopia, suggesting that lamb and goat might be a source of this pathogen for human infection if their infected meat is consumed undercooked or uncooked. Besides, the observed association of T. gondii seropositivity with reproductive losses may suggest the economic importance of the pathogen for the small ruminant producers. Therefore, it warrants control attention to reduce its economic and public health burden in the study areas. Further works on the economic impacts, bioassay, isolation, and genetic characterization of the pathogen are suggested.

Field evaluation of the efficacy of common anthelmintics used in the control of gastrointestinal nematodes of sheep in Dabat district, Northwest Ethiopia.

BACKGROUND: Gastrointestinal nematode (GIN) infections are the main impediments that restrict the welfare and productivity of small ruminant in the world. Effective management of GINs in grazing sheep relies heavily on the use of highly efficacious anthelmintic drugs. However, anthelmintic resistance is becoming a significant concern in the world, and this phenomenon severely threatens the potential utilisation of this control strategy. Therefore, this study was conducted 1) to evaluate the efficacy of commonly used anthelmintic on GINs in naturally infected sheep and 2) to assess the farmers' perception on anthelmintics utilisation practices in Dabat district, Northwest Ethiopia. METHODS: One hundred twenty nematode infected sheep were used in this study. Sheep were selected based on the egg count (≥150 eggs per gram of faeces). The animals were allocated randomly into four groups (30 animals per group). Group-I, II and III were treated with Albendazole, Tetramisole, and Ivermectin, respectively. The 4th group was left untreated (as control). Faecal samples were collected on day 0 (before treatment), on day 3, 7, 10 and 14 (post-treatment). The modified McMaster technique was used for quantifying the eggs. Faecal egg count reduction test (FECRT) was applied to determine the efficacy of anthelmintic at day 14 (post-treatment). In addition, a questionnaire survey was conducted on 100 randomly selected sheep owners. RESULTS: All anthelmintics tested revealed significant (P < 0.05) reduction in nematode egg excretion in the sheep post-treatment. Faecal egg count reduction (FECR) levels for Albendazole, Tetramisole, and Ivermectin were 97.2, 98.9 and 97.7%, respectively. Post-treatment egg counts and percentage reduction of egg counts were not significantly different (P > 0.05) among the treatment groups. The nematode genera identified before treatment were Haemonchus, Trichostrongylus, Cooperia, Trichuris, Teladorsagia, Bunostomum, and Strongyloides. Haemonchus and Trichostrongylus were detected after treatment with Albendazole and Ivermectin. The questionnaire survey revealed that Albendazole was the most commonly (90%) used anthelmintic to treat nematodes in sheep, followed by Tetramisole (36%) and Tetraclozan (Tetramisole-Oxyclozanide combination) (20%). Respondents expressed that anthelmintic selection was made based on veterinarian prescription (84%), colour (27%), efficacy (4%), price affordability (1%) and availability (1%). CONCLUSION: This study demonstrated that the tested anthelmintics had an acceptable level of efficacy against GINs of sheep.

Anthelmintic Resistance of Strongyle Nematodes to Ivermectin and Fenbendazole on Cart Horses in Gondar, Northwest Ethiopia.

A study was conducted from November 2015 to April 2016 to determine fenbendazole and ivermectin resistance status of intestinal nematodes of cart horses in Gondar, Northwest Ethiopia. Forty-five strongyle infected animals were used for this study. The animals were randomly allocated into three groups (15 horses per group). Group I was treated with fenbendazole and Group II with ivermectin and Group III was left untreated. Faecal samples were collected from each cart horse before and after treatment. Accordingly, the reduction in the mean fecal egg count at fourteen days of treatment for ivermectin and fenbendazole was 97.25% and 79.4%, respectively. It was significantly different in net egg count between treatment and control groups after treatment. From the study, resistance level was determined for fenbendazole and suspected for ivermectin. In addition, a questionnaire survey was also conducted on 90 selected cart owners to assess their perception on anthelmintics. In the survey, the most available drugs in the study area used by the owners were fenbendazole and ivermectin. Most respondents have no knowledge about drug management techniques. Hence, animal health extension services to create awareness regarding anthelmintic management that plays a key role in reducing the anthelmintic resistance parasites.