<abstract xmlns="http://www.w3.org/1999/xhtml">

<p>Q fever is a widespread disease affecting reproduction in dairy cattle. Several risk factors can increase the possibility of the herd becoming infected and the persistence of infection. The aim of this study was to characterise the dynamics of <italic>C. burnetii</italic> infection in affected herds and to evaluate reproduction problems and risk factors using a questionnaire within infected and infection-free dairy herds. In total, 25 farms that were serologically positive or shedding <italic>C. burnetii</italic> DNA in milk and 14 <italic>C. burnetii</italic> infection-free farms in Latvia answered the questionnaire. Ten positive herds were studied by testing individual blood and milk samples from up to 10 animals at two times separated by 7.5 to 13 months. The number of serologically positive and suspicious animals was higher in the second sampling even though several animals were culled. In the positive herds, the percentage of dystocia, stillborn calves and abortions during the last year was significantly (p=0.001; 0.01; 0.005, respectively) higher than in the negative herds. Several significant factors were found for the presence of Q fever infection, such as the herd size, the regional population density of ruminants, artificial ventilation systems, and frequent farm visitors. Deratisation was less practised in the negative farms and the presence of ticks was observed more often in the negative farms. Only two identified risk factors can be mitigated – the ventilation system and frequent farm visitors. The other factors cannot be changed arbitrarily but they have to be taken into account by decision makers.</p>
</abstract>

Q fever is a widespread disease affecting reproduction in dairy cattle. Several risk factors can increase the possibility of the herd becoming infected and the persistence of infection. The aim of this study was to characterise the dynamics of C. burnetii infection in affected herds and to evaluate reproduction problems and risk factors using a questionnaire within infected and infection-free dairy herds. In total, 25 farms that were serologically positive or shedding C. burnetii DNA in milk and 14 C. burnetii infection-free farms in Latvia answered the questionnaire. Ten positive herds were studied by testing individual blood and milk samples from up to 10 animals at two times separated by 7.5 to 13 months. The number of serologically positive and suspicious animals was higher in the second sampling even though several animals were culled. In the positive herds, the percentage of dystocia, stillborn calves and abortions during the last year was significantly (p=0.001; 0.01; 0.005, respectively) higher than in the negative herds. Several significant factors were found for the presence of Q fever infection, such as the herd size, the regional population density of ruminants, artificial ventilation systems, and frequent farm visitors. Deratisation was less practised in the negative farms and the presence of ticks was observed more often in the negative farms. Only two identified risk factors can be mitigated – the ventilation system and frequent farm visitors. The other factors cannot be changed arbitrarily but they have to be taken into account by decision makers.

<italic>Coxiella burnetii</italic> in dairy cattle herd: farming practices and infection dynamics

Latvia University of Life Sciences and Technologies

Rural Sustainability Research

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

 in dairy cattle herd: farming practices and infection dynamics

Q fever is a widespread disease affecting reproduction in dairy cattle. Several risk factors can increase the possibility of the herd becoming infected and the...

Coxiella burnetii in dairy cattle herd: farming practices and infection dynamics

Published Online: Jan 05, 2023

Page range: 09 - 23

Received: Oct 05, 2022

Accepted: Nov 28, 2022

DOI: https://doi.org/10.2478/plua-2022-0012

Keywords
Q fever, dairy cattle, shedding in milk, serological response, farming practices

© 2022 Guna Ringa-Ošleja, et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Coxiella burnetii in dairy cattle herd: farming practices and infection dynamics

Published Online: Jan 05, 2023

Page range: 09 - 23

Received: Oct 05, 2022

Accepted: Nov 28, 2022

DOI: https://doi.org/10.2478/plua-2022-0012

KeywordsQ fever, dairy cattle, shedding in milk, serological response, farming practices

© 2022 Guna Ringa-Ošleja, et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Q fever, dairy cattle, shedding in milk, serological response, farming practices