Epidemiology and field efficacy of anthelmintic drugs associated with gastrointestinal nematodes of sheep in Nejo district, Oromia, Ethiopia.

Gastrointestinal nematodes (GINs) are major constraints to health and productivity of small ruminants. Methods of their control relies mainly on anthelmintic drugs; however, the indiscriminate use of these drugs could lead to the development of anthelmintic resistance (AR). This study aimed to investigate the epidemiology of GINs infection, and field evaluation of anthelmintic efficacy in sheep. The epidemiological data were collected using a cross-sectional study design while a farm-based field study design was employed for the evaluation of anthelminthic efficacy. Furthermore, standard parasitological techniques were employed for qualitative and quantitative worm identification. The overall prevalence indicated 50.3%. Six genera of GINs (Haemonchus, Trichostrongylus, Oesophagostomum/Chabertia, Trichuris, Teladosargia/Ostertagia and Nematodirus) were identified. Among the identified genera, Haemonchus (25.4%) and Trichostrongylus (24.8%) were the dominant genera followed by mixed infection (21.8%), Oesophagostomum/Chabertia (10.4%), Trichuris (7.8%), Teladosargia (Ostertagia) (5.7%) and Nematodirus (4.1%). Mixed infections consisted either of double infections with Haemonchus and Trichostrongylus, or triple infections with Haemonchus, Trichostrongylus and Trichuris. The McMaster egg counting results showed that the mean EPG of infected sheep was 845.6. The results also showed 66 (34.2%), 101 (52.3%) and 26 (13.5%) sheep had low, moderate and heavy worm burden, respectively. Albendazole and Ivermectin showed low efficacy (percentage reductions = 90% and 92%; 95% lower confidence limit = 82.1% and 83.6% respectively) whereas Tetramisole was effective (FECR% = 96.8%; 95% LCL = 93.4%). Factors such as age, body condition, management system and past deworming history of sheep were found to have a statistically significant (p < 0.05) influence on the occurrence and burden of the worms. This is further explained as the highest prevalence and worm burden was detected in sheep of young age (p = 0.008; OR = 0.58; 95% CI = 0.39-0.87), poor body condition (p = 0.001; OR = 0.08; 95% CI = 0.04-0.16) and sheep kept under semi-intensive (p = 0.04; OR = 1.53; 95% CI = 1.02-2.29) with no deworming history for the last two months (p = 0.001; OR = 2.97; 95% CI = 1.94-4.56). The study results revealed that nematode infections were among sheep health constraints that could hurt their productivity while low efficacy of Albendazole and Ivermectin were detected. Therefore, the appropriate management techniques of GIN infections should be designed and implemented. Moreover, a further study involving more sensitive techniques (e.g. Mini-FLOTAC, molecular, and serological techniques) should be conducted by considering different host and environmental risk factors such as production level and seasons.

Prevalence of Cattle Trypanosomosis and Temporal Vector Distribution in Jima Arjo District, Upper Didessa Valley, Western Ethiopia.

Trypanosomosis is a protozoan disease, mostly transmitted by the tsetse fly, Glossina species, which causes severe disease of livestock in Ethiopia. The disease is also widespread across the globe especially in sub-Saharan African states. A cross-sectional study with the objectives of determining the prevalence of bovine trypanosomosis and assess the apparent densities of the disease vectors was conducted from October 2019 to July 2020 G.C in Jima Arjo district, east Wollega zone, Oromia regional state, Ethiopia. A parasitological study using conventional buffy coat technique was employed for the determination of prevalence of trypanosomosis and species was identified by Giemsa stain technique, while baited traps were used for the vector survey. The results of parasitological study revealed that the overall prevalence was 36 (8.2%) at 95% CI. From the total trypanosome positive animals 22 (5.0%), 8 (1.82%) and 6 (1.36%) of them harbor T. congolense, T. vivax, and T. brucei, respectively. Relatively higher prevalence (10.91%) was seen in animals with poor body condition than those with medium (7.38%) and good (5.55%), body condition though it is not statistically significant (P > 0.05). Higher infection rate was observed in male 26 (12.26%) than female 10 (4.39%) due to male cattle more exposed to the tsetse fly area or early released from home for drought reason. Out of the total positive animals, only 12 of them were anemic on buffy coat test of sampled blood. This justifies that animal could be positive for trypanosomosis without showing clinical sign of anemia which is the dominant sign in this disease. A total of 2185 vectors trypanosomes were collected among which 1,569 were tsetse flies and 616 were other biting flies. The density of Glossina species was 15.1 fly/trap/day. Glossina morsitans submorsitans and G. tachnoides were the two dominant species of tsetse flies recorded from the area. The present study indicated that tsetse and non-tsetse fly-borne trypanosomosis is a leading bottle neck for production and health of animals in Jima Arjo districts and similar case was found throughout the country which necessitates a coordinated vector and parasite control in order to alleviate the problem of the disease.

Prevalence and Factors Associated with Cryptosporidium Infection in Calves in and around Nekemte Town, East Wollega Zone of Ethiopia.

PURPOSE: Cryptosporidiosis, caused by a protozoan parasite of the genus Cryptosporidium, is a zoonotic disease that affects young animals and humans. The study was conducted from October 2020 to May 2021, with the objectives of estimating the prevalence of Cryptosporidium infection in calves and assessing the associated risk factors in Nekemte town, Ethiopia. METHODS: A cross-sectional study was adopted during the study period. Initially, 35 dairy farms were selected using a systematic study approach from which a total of 384 calves under the age of 12 months (75 calves from intensive, 51 from semi-intensive, and 258 from extensive dairy farms) were selected purposively for fecal sample collection. Fecal samples were collected directly from the rectum of each calf and tested for Cryptosporidium oocysts using Sheather's flotation and a modified Ziehl-Neelsen staining procedure. The data were analyzed using STATA statistical software version 13. RESULTS: Cryptosporidium infection was found in 53 of the 384 calves investigated, with an overall prevalence of 13.8% (95% CI = 8.1-17.6). Logistic regression analysis on the risk factors showed that types of farm, age, body condition scores, fecal consistency, types of feed, source of water, and farm hygiene were found to have a statistically significant influence on the shedding of Cryptosporidium oocysts by the calves (p < 0.05). Calves under the age of six months had a higher likelihood (OR = 2.7, 95% CI = 1.0-4.2, p < 0.001) of shedding the oocysts than the calves of 6 to 12 months of age. It was also confirmed that calves with poor body condition scores had a higher likelihood (OR = 2.6, 95% CI = 1.2-3.7, p=0.024) of shedding the Cryptosporidium oocysts than other ones. The likelihood of shedding a Cryptosporidium oocyst by the diarrheic calves was higher than by the nondiarrheic ones (OR = 3.1, p < 0.001). The infection was 2.6 times highest (16.8%, 31/185, 95% CI = 14.5-19.1, OR = 2.6, p=0.028) in calves feeding on grass alone, followed by milk and grass (15%) and milk (4.2%). Similarly, it was 2.2 times higher (18.5%, OR = 2.2, and p=0.002) in calves drinking river water than in calves drinking tap water. Moreover, calves kept under poor hygiene were more likely to shed Cryptosporidium oocysts (OR = 2.8, p=0.001) than calves kept under good hygiene. CONCLUSION: In conclusion, cryptosporidiosis is one of the health problems of calves in and around Nekemte town, East Wollega zone. Our findings confirmed that risk factors such as types of farm, age, body condition scores, fecal consistency, types of feed, water source, and farm hygienic status were found to have a significant effect on the occurrence of Cryptosporidium infection in the calves. While the molecular-based study is required to be carried out aiming at species identification and the epidemiology of the parasite, particular attention should be paid to the control of the disease in the study area.

Prevalence of Bovine Trypanosomosis and Its Associated Risk Factor in Hawa Galan District, Kelem Wollega Zone of Ethiopia.

An analytical cross-sectional study was performed between November 2015 and April 2016 at Hawa Galan woreda, Kelem Wollega Zone, Oromia Region, Ethiopia, to estimate the proportion of cattle with trypanosomosis and to evaluate the elements associated with the prevalence of bovine trypanosomosis. A haemoparasitological examination of the Buffy coat method was implemented to determine the proportion of trypanosomosis-positive cattle. A study population of 428 bovines was randomly selected from three peasant associations (PAs) and tested for the presence of the disease. Findings of the laboratory results indicate that among all animals tested at the study time, 26 (6%) animals were positive for the disease. Among the positive results, the proportion of trypanosome species was Trypanosoma congolense 18 (69.3%) and Trypanosoma vivax 8 (30.7%). The prevalence at the selected PAs was 12.5%, 3.8%, and 3% for Lemlem, Madawalkituma, and Ifajiru, respectively. From this finding, the relationship has a statistically significant variation (P < 0.05) among peasant associations and body condition state, and the proportion was significantly greater (P < 0.05) in animals categorized under poor body condition score. The relationships between age and sex of cattle show no statistically significant variation among them (P > 0.05). This study indicates that the proportion of trypanosomosis was greater in anemic (PCV<24%) cattle than nonanemic (PCV≥24%). Therefore, based on this finding, the proportion of bovine trypanosomosis is evident that can cause a major effect on the health of cattle in the study population in the study area. So, effective control methods could be applied to decrease the disease and its related economic loss.