Short communication: scoring system based on five teat morphology traits relates to udder health

Abstract

The aim of this study was to propose and verify a scoring system for the evaluation of udder susceptibility to mastitis, which combined five influential teat traits into one overall score for the udder. The traits included barrel diameter, apex diameter, canal length, the change in wall thickness, and the change in apex diameter. Teat morphology of 38 Holstein cows were measured twice during lactation by ultrasonography. Each teat was scored for the presence of traits with negative implications for the udder health at the start (ScoreLactStart) and the end of lactation (ScoreLactEnd). Results showed that cows with higher score had significantly worse udder health. The number of mastitis warning days was significantly correlated to both scores. In addition, ScoreLactEnd was correlated to somatic cell count (SCC) and lactose content. Each increase of ScoreLactEnd by 1 point represented an increase in SCC by 17,745 cells mL−1, 9.4 more days with mastitis warning, and 4.6 more days with SCC above 400,000 cells mL−1 during observed lactation. Only ScoreLactStart was significantly related to blood content, but relations to SCC were weaker compared to ScoreLactEnd. Ranking udders based on teat morphology traits show potential for detection of mastitis susceptible cows in commercial herds.

Keywords

• Dairy cow
• Holstein
• mastitis
• somatic cell count
• ultrasonography