TY - JOUR

T1 - The association between teat end hyperkeratosis and teat canal microbial load in lactating dairy cattle

AU - Paduch, Jan Hendrik

AU - Mohr, Elmar

AU - Krömker, Volker

PY - 2012/8/17

Y1 - 2012/8/17

N2 - Most pathogens that cause bovine mastitis invade the udder lumen through the teat canal. Amino acids and intercellular lipids may support microbial colonisation of the teat canal epithelium by pathogenic microorganisms. The aim of this study was to investigate the association between teat end hyperkeratosis, which is induced by machine milking, and teat canal microbial load. Contralateral teats, which differed in teat end hyperkeratosis scores, were identified in a split-udder experiment. The teat canal's microbial load was evaluated using the wet and dry swab technique. Staphylococcus (S.) aureus, Streptococcus (Sc.) uberis, Escherichia (E.) coli and other coliforms were detected by agar plate cultures. The positive detection of E. coli and the log10-transformed E. coli load of a teat canal were significantly associated with the teat end hyperkeratosis score (P<0.05). There were significant differences with respect to positive findings for E. coli, as well as the microbial load of E. coli and Sc. uberis, between the less-calloused and the more-calloused teat of a pair. For S. aureus, no significant associations between hyperkeratosis score and teat canal microbial load were detected. In general, a teat with a highly calloused teat end had an increased teat canal microbial load compared with the contralateral teat, characterised by a lower callosity. The results of the present study indicate that the environmental pathogen load is associated with teat end hyperkeratosis. Further research is needed to identify factors that may affect teat canal microbial load in lactating dairy cattle.

AB - Most pathogens that cause bovine mastitis invade the udder lumen through the teat canal. Amino acids and intercellular lipids may support microbial colonisation of the teat canal epithelium by pathogenic microorganisms. The aim of this study was to investigate the association between teat end hyperkeratosis, which is induced by machine milking, and teat canal microbial load. Contralateral teats, which differed in teat end hyperkeratosis scores, were identified in a split-udder experiment. The teat canal's microbial load was evaluated using the wet and dry swab technique. Staphylococcus (S.) aureus, Streptococcus (Sc.) uberis, Escherichia (E.) coli and other coliforms were detected by agar plate cultures. The positive detection of E. coli and the log10-transformed E. coli load of a teat canal were significantly associated with the teat end hyperkeratosis score (P<0.05). There were significant differences with respect to positive findings for E. coli, as well as the microbial load of E. coli and Sc. uberis, between the less-calloused and the more-calloused teat of a pair. For S. aureus, no significant associations between hyperkeratosis score and teat canal microbial load were detected. In general, a teat with a highly calloused teat end had an increased teat canal microbial load compared with the contralateral teat, characterised by a lower callosity. The results of the present study indicate that the environmental pathogen load is associated with teat end hyperkeratosis. Further research is needed to identify factors that may affect teat canal microbial load in lactating dairy cattle.

KW - Hyperkeratosis

KW - Mastitis pathogens

KW - Microbial load

KW - Teat canal

UR - http://www.scopus.com/inward/record.url?scp=84862542039&partnerID=8YFLogxK

U2 - 10.1016/j.vetmic.2012.02.032

DO - 10.1016/j.vetmic.2012.02.032

M3 - Journal article

C2 - 22445537

AN - SCOPUS:84862542039

VL - 158

SP - 353

EP - 359

JO - Veterinary Microbiology

JF - Veterinary Microbiology

SN - 0378-1135

IS - 3-4

ER -