# Impact of Host and Management Factors on Calf Morbidity and Mortality Rates in Smallholder Dairy Farms in Central Ethiopia: A Prospective Cohort Study

## TL;DR

This study in Ethiopia found that calf health on smallholder dairy farms is significantly impacted by management and environmental factors, with high rates of illness and death.

## Contribution

The study identifies specific risk factors for calf morbidity and mortality in smallholder Ethiopian dairy farms using a longitudinal cohort design.

## Key findings

- Diarrhea was the leading cause of calf morbidity and mortality, accounting for over half of both.
- Calving assistance and late colostrum intake were major risk factors for both morbidity and mortality.
- Farm location and birth site were strongly associated with calf mortality.

## Abstract

The dairy sector in Ethiopia is vital for the agricultural economy and smallholder farmers; however, calf morbidity and mortality present significant challenges. A prospective longitudinal study conducted tracked 204 newborn calves across 120 farms in central Ethiopia to estimate morbidity and mortality rates, identify causes, and assess risk factors. The calves were monitored every 15 days until they reached 6 months of age. Data analysis utilized Kaplan–Meier survival analysis and Cox proportional hazard regression. The study found a morbidity rate of 13.4 and a mortality rate of 4 cases per 100 calf-months at risk. Diarrhea was the most commonly diagnosed condition, accounting for 50.5% of morbidity and 64.5% of mortality. Key risk factors for morbidity included calving assistance (HR = 1.93), floor structure (HR = 2.88), calf sex (HR = 1.86), late colostrum intake (HR = 1.7), weaning age (HR = 0.47), dam breed (HR = 0.21), and calf age (HR = 0.23). Risk factors for mortality included farm location (HR = 0.25), calving assistance (HR = 7.7), birth site (HR = 27.3), floor structure (HR = 9.18), late colostrum intake (HR = 7.68), weaning age (HR = 0.03), and calf age (HR = 0.15). The observed morbidity and mortality rates exceed acceptable levels, jeopardizing calf health and dairy sector growth. Enhancing management practices—such as timely colostrum provision, early disease detection and treatment, and farmer education—is crucial to mitigate these rates. Further research is needed to pinpoint specific causes of calf morbidity and mortality in the study areas.