A Comparative Study on Pathological Changes in the Small Intestine of Sheep and Goat Experimentally Infected with Trichostrongylus colubriformis.

Background: Trichostrongylus colubriformis, also called hairworm, is a genus of parasitic roundworm affecting gastro-intestinal tracts of a ruminant. Gross and microscopic lesion characterizations and comparing its effect in the small intestine of sheep and goats experimentally infected with T. colubriformis were undertaken in the study. Methods: During the study period, 13 sheep and 14 goats were included in the experiment. The larvae of T. culibriformis were obtained from abattoirs and larvae were recovered by Bearmann techniques. The infective larvae of T. culibriformis (L3) as a single dose of 10,000 per-animal was administered orally to infected groups of sheep and goats. Blood was collected for hematological and serum biochemical analysis. Tissues for gross and histopathologic lesions characterization were collected from killed infected animals at 56 days. Results: From the infected group, the total recovered mean worm burden was recorded as higher in goats (P<0.05) than sheep, with an establishment rate of 50.16% and 34.46%, respectively. The total mean PCV, Hb, and albumin values recorded in the infected groups of sheep and goats were significantly (P<0.05) lower than non-infected control of both animal groups. In goats, the total serum protein was significantly (P<0.05) lower in the infected group than the non-infected control group. Gross lesions found were enteritis with petechial hemorrhages, edema, hyperemia, and mucosal slough, which were marked in the duodenum (62.69%) and jejunum (33.33%) in sheep and 47.05% duodenum and 45.09% jejunum in goats. The microscopic lesions developed by T. colubriformis were subtotal villus atrophy, hemorrhage, straightened and elongated dilated crypts, loss of epithelium, mucosal erosion, and infiltration of inflammatory cells. Conclusion: The present study showed that T. colubriformis infection caused physiological and pathological changes of the small-intestine in sheep and goats, with more severe infection in goats than sheep, although they were under the same management condition.

Seroprevalence and Associated Risk Factors of Mycoplasma gallisepticum Infection in Poultry Farms of Hawasa and Bishoftu, Central Ethiopia.

Background: Mycoplasma gallisepticum (MG) infection is an economically important respiratory disease in the poultry production system worldwide. It is characterized by rapid transmission and causing many obstacles to poultry industries in different parts of Ethiopia. Methods: A cross-sectional study was employed from January to September 2021 to estimate the seroprevalence and associated risk factors of MG in domestic layer chickens in large and small commercial poultry farms in Hawassa and Bishoftu area, Ethiopia. A total of 368 blood samples were collected. Data were analyzed using SPSS version-20, reported as percent prevalence, and Pearson's chi-square was used to assess the association between factors considered to have association with MG infection. The samples were processed by using an indirect ELISA (ProFLOKIBV, USA) test coated with antibody against MG. Results: The total seroprevalence of MG infection was found to be 70.65%. Significant variation in environmental risk factors with seroprevalence was assessed and the higher prevalence of MG was significantly (χ 2 = 14.42; p < 0.05) higher in layer chicken farms found in Bishoftu. Likewise, it was significantly observed in the adult chicken and commercial production system. There were significant difference between breeds and ages of birds with the occurrences of MG (χ 2 = 19.60 and χ 2 = 17.46, respectively). Management related risk factors found around the types of farms were significantly different with the occurrences of MG (OR = 52.5; p < 0.05). Conclusion: The evidence from seroprevalence of the MG infection in the current finding provides an indication of the eminence of infection in the study areas. Moreover, it provides an insight on the prevalence of MG infection and further molecular characterization of the organism needs to be conducted in the areas. Biosecurity measures combined with vaccination and sero-monitoring should also be implemented in the farms.

Seroprevalence of Infectious Bronchitis Virus in Broiler and Layer Farms of Central Ethiopia.

Background: Infectious bronchitis virus (IBV) is a highly contagious viral disease of chicken typically affecting the reproductive and respiratory tract and results in possible economic causes from its serious infectious and transmission characteristics. Methods: A cross-sectional study was carried on serum samples of chickens selected from six (two commercial and four small holder) farms and two types of production (broiler and layer) to detect seroprevalence of IBV and its associated risk factors in Bishoftu and Holeta areas of central Ethiopia from June 2021 to September 2021. A total of 354 blood samples were collected and subjected to indirect ELISA test by IBV antibody test kit ((ProFLOK IBV), from ProFLOK Laboratories Inc., (USA)) to detect specific antibodies against IBV. Results: Overall, 97.46% seroprevalence was identified. From 230 and 124 samples collected from commercial and smallholder poultry farms, 226 (98.26%) and 119 (95.98%) positive results were obtained, respectively. Among the production types of chickens, high seroprevalence (99.31%) was found in layer poultry, and lower seroprevalence (96.17%) was found in the case of broiler chicken. Significant association was observed among different associated risk factors particularly age, sex, breed, and production types of chickens. From the tested chickens, all age groups, species, and farm types have high seroprevalence of IBV. The prevalence of IBV was highly significant (p ≤ 0.01) in the study site. The risk factors indicated could have increased infection prevalence, pathogens' economic impact, and disease occurrence. Conclusion: IBD is complicating factor affecting poultry production systems in the area. Vaccine and biosecurity measures are recommended for the control of IBV. Furtherly, identification and characterization (by using RT-PCR) of persistent serotype of IBV circulating in the field are recommended.

Seroprevalence and Associated Risk Factors of Infectious Bursal Disease in Chickens Managed Under Intensive and Backyard Production Systems in Western Oromia, Ethiopia.

BACKGROUND: Infectious bursal disease (IBD) is a highly contagious viral disease challenging poultry industry throughout the world. It is also among the main obstacles in the different chicken production system in Ethiopia. This study was conducted with the aim of determining seroprevalence and associated risk factors of IBD in backyard and intensively managed chickens of the study area. METHODS: A cross-sectional study was conducted in selected districts of western Oromia on intensive and backyard production systems to investigate seroprevalence of IBD and associated risk factors from September 2020 to August 2021. A total of 384 chickens of either sex, 128 from each district, were included from three randomly selected peasant associations (PAs). In addition, 180 individual poultry keepers, of both sexes, and different educational backgrounds, were included for questionnaire survey (Supplementary Material). Data were analyzed using SPSS Version-20, and results were presented as percentages. The samples were processed by using (ProFLOKIBV, USA) indirect enzyme-linked immunosorbent assay (I-ELISA) kits. RESULTS: Out of 384 serum samples tested, 66.93% (n = 257) were found positive by indirect ELISA. The highest prevalence was recorded from Sasiga district Balo Bareda PA. Prevalence of IBD showed significant statistical association (p < 0.05) among owner education level, chicken rearing practice, origin and breed. Questionnaire survey results showed the majority of respondents lack sufficient knowledge about IBD and other chicken diseases. The practice of backyard chicken producers on vaccination and treatment of sick birds is limited. CONCLUSION: In conclusion, IBD is a major factor hindering production and health of birds. Proper vaccination programs coordinated with awareness creation of chicken owners on how to isolate and treat sick birds should be implemented.