Year: 2005
Type: other
Abstract: The objective of the present study was to identify cow risk factors associated with\ndevelopment of clinical mastitis (CM) in subsequent stages of lactation. A total of\n3,309 lactations from spring-calving Holstein-Friesian cows were included in the\nanalysis; parity number ranged from one to three, inclusive. A generalised estimating\nequations approach with a logit link function was used to account for the binary\nnature of the data and the unequal number of repeated records per cow. The dependent\nvariable was the probability of developing CM in the subsequent stage of lactation.\nIndependent variables included in the model were chosen using stepwise selection;\nherd, year of birth, month of calving, parity, period of lactation and previous CM history\nsignificantly affected the probability of CM. Two-way interactions between parity\nand period of lactation and between parity and incidence of CM in the previous lactation\nwere also included in the model. A greater probability of developing CM is\nexpected in cows that experienced CM in the previous lactation and/or previously\nwithin the same lactation. The probability of CM occurring in cows that experienced\nat least one case of CM in the previous lactation was 0.92 to 3.75 times that of a\ncow that experienced no CM in the previous lactation. It is possible to predict the\nprobability of an animal developing CM in the subsequent stage of lactation when\ninformation is available on the parity and month of calving of the animal and its previous\nhistory of CM.
Authors: D.P. Berry, William J. Meaney
Language: English
Subfield: Animal Science and Zoology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2148507243