摘要 : Lamb morbidity and mortality cause significant loss in a smallholder production system. A longitudinal prospectivesurvey was conducted on 408 randomly selected farmers located in six purposefully selected kebeles in Gewataworeda f... 展开 Lamb morbidity and mortality cause significant loss in a smallholder production system. A longitudinal prospectivesurvey was conducted on 408 randomly selected farmers located in six purposefully selected kebeles in Gewataworeda from June 2020 to July 2021 to determine the incidence of morbidity and mortality in lambs and to identifyrisk factors. For this purpose, 408 lambs from the Gewata district’s mixed crop-livestock production system wereexamined every day from birth to three months of age. The data was analyzed using the Kaplan-Meier (K-M) method,the log-rank test, and Cox proportional hazards regression. Results showed that the cumulative incidence of allcauseof morbidity and mortality at the end of three month was 12.86% (95% CI: 10.26–16.13%), and 6.86% (95% CI:5.03–9.35%), respectively. Diarrhea was the leading cause of morbidity and mortality, accounting for 49.33 and 50%morbidity and mortality, respectively. Pneumonia was the second most frequent cause of morbidity and death. In theK-M hazard analysis, the greatest risk of lamb morbidity and mortality was observed during the first month of life, andthen the risk decreased significantly as the lamb grew. Of the 17 potential risk factors studied, the multivariable Coxproportional hazards regression model showed that lamb sex, birth weight, umbilical care, time and method of colostrumfeeding were the five predictors that were significantly associated with a higher risk of morbidity, whereas birthweight, lambing difficulty, dams’ parity, method and time of colostrum feeding were the five predictors that weresignificantly associated with a higher risk of mortality. Moreover, a higher risk of morbidity was observed in lambswith methods of colostrum feeding after birth (HR = 3.158;p = 0.000) and with variations in birth weight (HR = 1.418;p = 0.003). Similarly, the mortality risk was 4.926 (p = 0.047), 4.023 (p = 0.012), and 3.206 (p = 0.000) times higher inlambs with lambing difficulties, at the time of colostrum feeding, and by the method of colostrum feeding, respectively.According to this research, lamb morbidity and mortality rates in the study area are significantly high whichhas a great impact on the replacement stock and production. Hence, awareness should be created among farmersconcerning improved lamb management practices. 收起