Seroprevalence of Mycoplasma gallisepticum in domestic chickens, East Shewa, Ethiopia

Cross sectional study was conducted to estimate the sero-prevalence of Mycoplasma gallisepticumin domestic chickens and to assess risk factors associated with the disease in commercial and local chickens in East Shewa, Ethiopia. A total of 514 sera were collected (from187 commercial chickens and 327 local chickens) and tested using an indirect enzyme linked immunosorbant assay (ELISA) to detect antibodies against M. gallisepticum. The overall seroprevalence of M. gallisepticum was 49.4% (254/514). A statistically significant association (p<0.05) was observed in prevalence between chicken type with prevalence of 64.5% in local and 23% in commercial chickens. Variation in prevalence was observed among the three commercial farms, the highest being in farm-B (46.8%) and the lowest in farm-C (4.25%). Prevalence in local chickens was significantly highest in Lume (72.7%) and lowest in Ada’a (47.5%) (p<0.05). Age was significantly associated with sero-prevalence (p<0.05). Prevalence was 67.3% in layers of (18 to 76 weeks) and 0% in layer chicks of (1 to 8 weeks old). Prevalence was also significantly different between layers (41.7%) and broilers (7.8%) (p<0.05). In commercial chickens, prevalence was significantly higher in females (32.4%) than males (10.1%) (p<0.05). The current study revealed M. gallisepticum is prevalent in chicken in East Shewa, Ethiopia.Keywords: Domestic chickens; East Shewa; Ethiopia; Mycoplasma gallisepticum; Sero-prevalenc

Socioeconomic Assessment of a Tsetse and Trypanosomosis Control Program in Southwest Ethiopia

A socioeconomic study was made to assess the outcome of a tsetse and trypanosomosis control operation conducted in Chewaka settlement station, Southwest Ethiopia, during 2005-2007 through comparisons of data before and after the control program within Chewaka, and between Chewaka and a non-controlled adjacent site, Bikiltu Didessa peasant Association. Retrospective and crossectional questionnaire survey methods were used to generate data for the study. Results showed that the total livestock and cattle population in chewaka increased by 116% and 1039 %, respectively, and the total cereal production increased by 63.2 %. During this period the overall livestock and cattle population in Bikiltu decreased by 45.7% and 47.5%, respectively, and the total cereal production declined by 35.6%. The average number of cattle bought per house hold per year in Chewaka, 1.15 head, was significantly higher (P=0.000) than the average number of 0.55 head in Bikiltu. The chances of cattle and oxen mortality in Bikiltu were 10 and 6 times (OR= 6.5 and 10.2) more likely than in Chewaka and the chance of abortion in cows in Bikiltu was more than 10 times as compared to Chewaka (OR=10.79). The control operation in chewaka settlement station resulted in rapid growth of livestock and crop production, fast expansion of farmland, improved income from animal sell and increased animal purchasing power

Comparative evaluation of the immune responses of seven chicken ecotypes to vaccination against Newcastle disease

Newcastle disease (ND) is a highly contagious viral disease of poultry with high mortality. The local velogenic viral pool of the ND strains  influences its severity and occurrence. ND vaccination is the most feasible approach to control the disease. However, some ND-vaccinated groups within chicken populations are susceptible to velogenic ND infection developing outbreaks with marked pathological lesions and shedding of the virus. Vaccine strain-related factors as well as inadequate vaccine application and delivery methods during vaccination might explain the suboptimum ND vaccine efficacy. In this study, however, we propose that host factors may contribute to the suboptimal vaccine efficacy in vaccinated chickens. We, therefore, compared the immune response of five Ethiopian chicken ecotypes to ND  immunization in the presence of two reference breeds (Fayoumi and Bovans). All chickens received initial immunization at age of 21 days with HB1 ND vaccine followed by two-times LaSota booster immunization at age 50 and 120 days. Subsequently, serum was collected fortnightly post-vaccination at age 35, 65, and 135 days for immune response analysis using the hemagglutination inhibition (HI) test. HIantibody was significantly higher at days 135 > 65 > 35 in each ecotype following the third, second, and first vaccination, respectively. The different chicken ecotypes had significant differences in HI antibody response to the ND vaccination. Accordingly, the HI titer was  significantly higher in Jarso > Cheffe > Fayoumi > Arsi > Bovans > Tepi > Horro suggesting antibody titer and ND vaccine efficacy of the ND vaccine depends on host factors. Moreover, some chicken groups within each ecotype had low HI titer. Chicken ecotypes with weak immune responses may not completely clear the virus from their body; thus, they can serve as a reservoir host by maintaining the ND  virus. We conclude that herd immunity level and blanket vaccination program based on the results of a single host genetic group can be misleading during developing and recommending a new vaccine. Hence, understanding the host determinant factors in the immune response during vaccination can lead to improved efficacy and protection against ND in chicken populations

Journal of Veterinary Medicine and Animal Health

Participatory epidemiology and associated risk factors of foot-and-mouth disease in cattle in South Omo zone