Conférences et affiches

In the province of Quebec, Canada, the dairy sector is the most important agricultural production in cash receipts. This province has also been the national leader in terms of herd size of dairy cattle and the number of farms. However, in Quebec, 86% of cows are still housed in tie stalls and, thus, they are always attached without possibility to exercise. However, previous research works have demonstrated the benefits of increasing movement opportunities for dairy cows, such as decreased lameness and leg injuries. On the other hand, the gas emissions generated during cow exercise can become more important due to an increase in soiled surfaces, which poses a greater potential for becoming an environmental threat to air quality. Research on the characterization of gas emissions in dairy production (NH3, CO2, CH4 and N2O), either from manure management or natural digestive process, has been exhaustive. However, compared to conventional practices, a new configuration of livestock buildings with dedicated exercise areas for a better welfare might produce different gas concentrations and emissions. New factors must therefore be determined. Hence, the paper will present punctual floor emission measurements on dairy research farm to evaluate the environmental impact of indoor and outdoor exercise zones in comparison with a conventional tie stall.