Study on clinically manifested reproductive health problems of dairy cows managed under intensive and semi-intensive production systems in Wondo Genet district, Southern Ethiopia

Reproductive disorders in cows are crucial as reproduction and fertility are the two key pillars of dairy production profitability. The study was conducted to identify and estimate the prevalence of clinically manifested postpartum reproductive disorders, to identify the associated risk factors and to estimate the sero-prevalence of brucellosis in dairy cows kept under intensive and semi-intensive dairy farms in Wondo Genet district from November 2019 to September 2020. Out of the total 205 cows examined, 90 cows (43.90%) had at least one of the reproductive problems identified by either questionnaire interview or regular follow up of individual cows. Out of 146 cows retrospectively and 59 cows prospectively assessed for the presence of any reproductive disorder, 62 (42.47%) and 28 (47.46%) cows had at least one reproductive disorders, respectively. Retained fetal membrane, abortion, uterine infections, anestrous and repeat breeding are the major reproductive disorders encountered followed by dystocia, milk fever and prolapses of the vagina and/or uterus. Among the considered host and management related risk factors, only presence of previous reproductive disorder had statistically significant association with the occurrence of reproductive disorder (p<0.05). This study also demonstrated that none of the serum samples collected from Wondo Genet and other towns (namely Hawassa, Wolaita Sodo and Arsi Negelle) and tested using Indirect Multi-species ELISA was positive for bovine brucellosis. Further studies, preferably laboratory based, should be conducted to identify the underlined causes of these problems in different parts of the country. Meanwhile, awareness should be created to farm owners/attendants to improve their farm management system

Prevalence, risk factors and bacterial causes of bovine mastitis in southern Ethiopia

Mastitis is one of the most economically important diseases in dairy farms worldwide. It is particularly important in Ethiopia where no routine prevention and control practices are in place. This cross-sectional study was carried out between October 2017 and June 2018 to estimate the prevalence of mastitis, identify the associated risk factors and isolate bacterial causes in dairy farms located in southern Ethiopia using standard microbiological methods and questionnaire survey. A total of 686 lactating cows which were found in 122 selected dairy farms were investigated by physical examination and California mastitis test. The overall cow-level prevalence of mastitis was 54.2% (95% CI: 50.5 – 57.9%). Based on the study site, the prevalence was 55.7% in Hawassa, 54.3% in Arsi Negele, 52.6% each in Wondo Genet and Wolayta Soddo towns with no significant (p > 0.05) difference among the sites. The majority of mastitis cases were subclinical (48.1%) while the clinical mastitis was only 6.1%. Of the 122 herds tested, 109 (89.3%; 95% CI: 82.1 – 93.9%) had at least a cow positive for mastitis. The study showed that high parity number (OR = 1.6; p = 0.015), flat (OR = 4.5; p <0.001) and round (OR = 2; p <0.001) teat end shape, history of mastitis in preceding lactation (OR = 3.3; p <0.001), and slightly (OR = 3.5; p < 0.001), moderately (OR = 4.9; p < 0.001), and very dirty (OR = 9.2; p < 0.001) udder and legs were the major risk factors which are significantly associated with higher prevalence of mastitis. Based on the available media and reagents, the major bacteria isolated from subclinical mastitic milk samples were Staphylococcus spp. (57.3%), Streptococcus spp. (18.6%), E. coli (17.3%) and Bacillus spp. (7.5%) in order of their abundance. The present study revealed a high prevalence of mastitis, particularly the subclinical one, and the associated risk factors. Enhancing the awareness of dairy farmers, regular screening of cows for subclinical mastitis, proper treatment of the clinical cases, improving the hygienic condition of the cows, and culling of chronically infected cows are critically important to prevent and control bovine mastitis. Keywords: Mastitis, Prevalence, Risk factors, Southern Ethiopi

Dairy cattle lameness prevalence, causes and risk factors in selected farms of southern Ethiopia

A cross-sectional study was conducted from October 2018 to December 2019 to estimate the prevalence of lameness in dairy cows, to  assess the causes and associated risk factors in southern Ethiopia. A total of 2009 dairy cows were visually and clinically examined, and the overall prevalence of lameness was found to be 14. 1% (95% CI=12.7-15.7). The prevalence of lameness was significantly (P< 0.05) higher in Arsi Negelle, Yirgalem, and Wolaita Sodo than in Wondo Genet and Hawassa. The prevalence of lameness was also associated with the stages of pregnancy and parity (P < 0.05). Generally, the prevalence of lameness in dairy cows was increasing with the increase in parity and stage of pregnancy. The main abnormalities observed in this study were hooves overgrowth (6%), lesions between hooves (4%), lesions on legs (2.2%), trauma (0.6%), arthritis (0.5%), and a sole ulcer (0.3%). Most of these abnormalities were mainly due to faulty  management. Hence, based on this finding it is recommended that hoof management and trimming are very essential components of lameness control. Furthermore, early detection and treatment of lame cows; training of the owners on hoof management; and  improvement of the housing are helpful to keep lameness at a lower level