Prevalence and risk factors associated with downer cow syndrome at smallholders dairy farms in Middle Egypt

Objective:   This study was conducted to determine the prevalence and risk factors associated with downer cow syndrome (DCS) in Middle Egypt.
Design: Case-control study
Animals: A total of 1,300 cross breeding Holestein dairy cattle in 30 small scale farms were involved in the study during the period from September 2018 to August 2019.
Procedures: Three hundred and twenty downers (24.6 %) were investigated and were subject to clinical examination. A questioner to farm owners was designed focusing on risk factors for occurrence of downers.
Results: The prevalence of  downers due to metabolic, digestive, infectious, musculoskeletal and nerve injuries was 8.1%, 6.9%, 5.4%, 2.3% and 1.9%, respectively. Multivariate logistic regression analysis showed that conventional ration (OR: 2.8, CI 95%: 4.3-6.2), indoor housing (OR 3.4, CI 95% 2.1-3.7), inadequate hygienic measures (OR: 2.05, CI 95%: 4.55-6.5), concrete flooring (OR: 3.89, CI 95%: 1.4-10.9), > 20 kg daily milk yield (DMY) (OR: 3.037, CI 95%: 1.46-6.34), poor body condition score (BCS) (OR: 20.6, CI 95%: 6.6-6.9), older age (OR: 1.05, CI 95%: 1.05-2.20), first 45 days in milk (DIM) (OR: 12.4, CI 95%: 3.3-4.3), and winter (OR: 1.47, CI 95%: 0.16-1.36) were potential risk factors. DCS showed an association with hyperthermia (P<0.01), tachycardia (P<0.01), polypnea (P<0.01), ruminal hypomotility (P<0.01) and inappetence (P<0.01).
Conclusion and Clinical relevance: The present results indicate that DCS is a prevalent issue at smallholders dairy farms. It is mainly due to metabolic causes. Appropriate control strategies are recommended, focusing mainly on the potential risk factors identified in this study.