Relationship between udder and teat conformation and milk yield performance in dairy cows pre- and post-milking
The objectives of this study were to determine the relationship between udder floor area (UFA) and milk production traits in dairy cows, pre- and post-milking, as well as to examine the usefulness of a simple method of measuring UFA. The absolute reduction (AR, cm2) and relative reduction (RR, %) in UFA post-milking relative to pre-milking was calculated. Absolute reduction was influenced by breed and lactation stage, but not by parity of the cows (P < 0.05). There was no effect of breed and stage of lactation on the RR of UFA. Moderate correlations were observed between absolute reduction of UFA and daily milk yield (r2 = 0.422), lactation milk yield (r2 = 0.426), and absolute fat yield (r2 = 0.515) (P < 0.01 and P < 0.05). Moderate and weak correlations were found between RR of UFA and daily milk yield (r2 = 0.335) (P < 0.01), AR of the udder area and the 305-d lactation milk yield (r2 = 0.326) (P < 0.10). It was concluded that measuring UFA using the method described may be useful for the selection of dairy cattle mammary conformation traits. Key words: Dairy cow, udder and teat conformation, milk production traits, measurement technique