Prevalence study on bovine mastitis in the Adamawa Region of Cameroon

Introduction - Mastitis is a serious health and economic problem in the bovine dairy industry worldwide. In Cameroon, the situation of this disorder is poorly understood and worrisome especially as the dairy industry is not well developed. Exact knowledge from the epidemiological data of the subclinical and clinical mastitis would lead to the creation of a better control program in Cameroon where the most efforts are concentrated on the treatment of clinical cases. Aims - In order to fill the gap in terms of prevalence of subclinical and clinical mastitis, identify the most important bacterial agents and evaluate the associated risk factors, a field cross sectional study was carried out in Adamawa Region. Materials and methods - Two hundred and forty randomly selected local zebu and crossbreds lactating cows reared in small or large farms of Adamawa Region (Cameroon), were examined for clinical and subclinical mastitis by a combination of California Mastitis Test (CMT) and clinical examination of the udders. For each positive cow, microbiological cultures were performed. STATA software (13.0) was used for data analysis. Results - Overall, 164 (68.3%) of 240 cows were affected from mastitis. In particular, 144 (60%) and 20 (8.3%, n=240) lactating cows were positive for subclinical and clinical mastitis, respectively. At quarter level, 546 (56.9%, n=960) were sub-clinically (51.2%) or clinically (5.6%) affected. The Adamawa Gudali crossbreeds (76%), Holstein-Friesian (71.7%), Red Fulani (65.7%), showed significantly (P<0.05) higher rates of subclinical infection. Risk factors like herd size, breed, age, parity, the lactation stage, and the daily milk yeld, significantly affected the prevalence (P<0.05) in particular of subclinical mastitis. Staphylococcus spp. (33.8%), Streptococcus spp. (26.4%) and Escherichia coli (22.0%) were the predominant bacteria recorded. Discussion - The findings revealed a high prevalence of subclinical bovine mastitis in the Adamawa Region of Cameroon. Although, most cases were largely of suspected environmental origin, several risk factors related to productivity and the management were significantly involved. Conclusions - This is the first epidemiological study carried out in this Region. The results indicate that mastitis could be among major constraints that limit optimum productivity of large and small holder dairy cattle farms in Cameroon, confirming the importance of the introduction of cow mastitis control and prevention programs. KEY WORDS Adamawa Region-Cameroon, Bovine mastitis, Prevalence, Pathogens, Risk factors.