- Oral presentation
- Open Access
Comparison of Production Diseases of Cows Kept in Cold- and Warm Loose Housing Systems in Finnish Dairy Herds
© The Author(s); licensee BioMed Central Ltd. 2003
- Published: 31 March 2003
- Confidence Limit
- Risk Ratio
- Disease Incidence
- Farming System
- Multivariable Model
Finland's cold loose housing systems (CLH) for dairy cows have been compared to the more traditional warm loose housing systems (WLH) in regard to the incidences of udder and ovarial disorders, ketosis, parturient paresis and metritis. For both systems approximately 10,000 calvings on 210 farms during the years 1996 and 1997 were modelled using survival analysis and two-level logistic regression in an observational cohort study.
The results of the different multivariable models, the modelling process, model diagnostics and sample size and confidence limit analysis were combined in an attempt to estimate an unbiased risk ratio.
The estimated risk ratios show that there are some differences in the incidence of production diseases between the 2 farming systems. It could be seen from the diagnostics that they were influenced considerably by the modelling process and some 'influential farms'. Even though some disease incidences differed statistically significantly, the observed differences were small so that we concluded that they should not influence the farmers decision making about whether or not to build a CLH in Finland.
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.