title: The prevalence of heifer mastitis and its associated risk factors in Huanggang, Central China.
abstract: The purposes of this study were to determine the prevalence of heifer clinical mastitis (HCM) and heifer subclinical mastitis (HSCM), isolate HCM-causing bacteria, and assess the association of some risk factors in Huanggang, Central China. A total of 1,374 lactating heifers from three dairy farms were examined in the present study; 22.64% of heifers were positive for mastitis, out of which, 3.86 and 18.78% were with HCM and HSCM, respectively. Of the 67 HCM samples, 91.05% were single growth, 7.46% mixed growth, and 1.49% no bacterial growth. Coagulase-negative staphylococci (CNS) accounted for 30.98% of the isolates followed by Escherichia coli (29.58%), Staphylococcus aureus (16.9%), and Streptococcus uberis (11.27%). Logistic regression analyses showed that heifer milk yield lower than 3 L had the highest prevalence of HCM compared to heifer milk yield of more than 3 L (P < 0.01), and prevalence of HCM was significantly high in heifers with the presence of teat lesions (P < 0.01). Moreover, the heifer milk yield lower than 3 L had the highest prevalence of HSCM compared to heifer milk yield of more than 3 L (P < 0.01). These two factors were significantly associated with the occurrence of heifer mastitis, which needs to be considered in the prevention and control strategies of the disease.
authors.affiliation: College of Animal Science, Yangtze University, Jingmi Road 88#, Jingzhou, People's Republic of China.
authors.forename: Feng Li
authors.initials: FL
authors.lastname: Yang
authors.forename: Chen
authors.initials: C
authors.lastname: Shen
authors.forename: Bao Xiang
authors.initials: BX
authors.lastname: He
authors.forename: Yu Ying
authors.initials: YY
authors.lastname: Yang
authors.forename: Da Chun
authors.initials: DC
authors.lastname: Gong
authors.forename: Xiao Shan
authors.initials: XS
authors.lastname: Li
mesh_terms: D000818:Animals; D002417:Cattle; D002681:China / Q000453:epidemiology; D003612:Dairying; D004926:Escherichia coli / Q000302:isolation & purification; D005260:Female; D005506:Food Contamination; D005516:Food Microbiology; D007774:Lactation; D008321:Mammary Glands, Animal / Q000382:microbiology; D008414:Mastitis, Bovine / Q000453:epidemiology / Q000382:microbiology*; D008892:Milk / Q000382:microbiology; D016017:Odds Ratio; D015995:Prevalence; D012044:Regression Analysis; D012307:Risk Factors; D013211:Staphylococcus aureus / Q000302:isolation & purification; D013291:Streptococcus / Q000302:isolation & purification