A longitudinal study of the dynamics of Mycoplasma bovis antibody status in primiparous cows and bulk tank milk in Swedish dairy herds

Abstract

Mycoplasma bov/s is an important pathogen causing pneumonia, mastitis, and arthritis in cattle all over the world entailing reduced animal welfare and economic losses. In this longitudinal study, we investigated the presence ofM. bov/s antibodies in bulk tank milk (BTM) and in milk from primiparous (PP) cows at 4 sampling occasions over 2 yr. Herd characteristics associated with a positive antibody test result in PP cows were investigated. The participating dairy herds (n = 149) were situated in southern Sweden, samples were collected and analyzed with ID Screen antibody ELISA. Information on herd characteristics was retrieved from the national DHI database. To identify herd characteristics associated with the presence of antibodies in PP cows, mixed linear regression with herd and sample as random factors were used. The apparent herd-level prevalence of M. bov/s infection based on antibodies in BTM was 17%, but with the addition of PP cows, the prevalence increased to 28%. The results showed that larger herds and introduction of cattle was associated with higher antibody levels in PP cows. In conclusion, this study showed a clear difference in the apparent prevalence ofM. bov/s infection based on antibodies in BTM or in PP cows: The number of positive herds was almost doubled when including PP cows. This motivates repeated sampling of a few PP cows to find newly infected herds in an early stage. Finally, the results showed that introduction of cattle influences the level of M. bov/s antibodies. This is important in the control and prevention of further spread of the infection. It is essential for free herds to know their M. bov/s status, and antibody testing is highly recommended if introducing cattle.

Keywords

heifers; ELISA; Mycoplasmops/s bov/s; external biosecurity

Published in

Journal of Dairy Science
2025, volume: 108, number: 1, pages: 845-855
Publisher: ELSEVIER SCIENCE INC

SLU Authors

• Hurri, Emma

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    
  • National Veterinary Institute (SVA)

• Alvåsen, Karin

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

• Tråven, Madeleine

  • Department of Clinical Sciences, Swedish University of Agricultural Sciences
    

UKÄ Subject classification

Animal and Dairy Science
Pathobiology

Publication identifier

• DOI: https://doi.org/10.3168/jds.2024-25304

Permanent link to this page (URI)

https://res.slu.se/id/publ/140322