HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Free Via Open Access Full Text Full Text (PDF) Interpretive Summary Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Google Scholar Articles by Breen, J. E. Articles by Green, M. J. PubMed PubMed Citation Articles by Breen, J. E. Articles by Green, M. J.

Quarter and cow risk factors associated with a somatic cell count greater than 199,000 cells per milliliter in United Kingdom dairy cows

J. E. Breen^1,*, A. J. Bradley^* and M. J. Green

^* Department of Clinical Veterinary Science, University of Bristol, Langford House, Langford, Bristol BS40 5DT, United Kingdom
School of Veterinary Medicine and Science, The University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Leicestershire, LE12 5RD, United Kingdom

¹ Corresponding author: James.Breen{at}bristol.ac.uk

Quarter and cow risk factors associated with a somatic cell count (SCC) >199,000 cells/mL at the next milk recording during lactation were investigated during a 12-mo longitudinal study on 8 commercial Holstein-Friesian dairy herds in Southwest England, United Kingdom. The individual risk factors studied on 1,677 cows included assessments of udder and leg hygiene, teat-end callosity and hyperkeratosis, body condition score (BCS), and measurements of monthly milk quality and yield. The outcome variable used for statistical analysis was the next recorded individual cow SCC >199,000 cells/mL. Statistical analysis included use of generalized linear mixed models. Significant covariates associated with an increased risk of SCC >199,000 cells/mL were increasing parity, increasing month of lactation, previous SCC (SCC 200,000 cells/mL and greater, odds ratio = 7.12), and cows with a BCS <1.5 (odds ratio = 2.09) or BCS >3.5 (odds ratio = 2.20). Significant covariates associated with a reduced risk of SCC >199,000 cells/mL were cows with contamination of the skin of the udder and quarters with mild (odds ratio = 0.65) and moderate (odds ratio = 0.62) hyperkeratosis of the teat-end. These results suggest that individual quarter and cow-level factors are important in the acquisition of intramammary infections as measured by SCC during lactation. Cow energy status, as measured by BCS, may influence the risk of intramammary infection during lactation.

Key Words: somatic cell count • risk factor • body condition score • hyperkeratosis