The aim of the research was through a study of four areas of satisfaction of the biological requirements of animals to make ethological evaluation of abuilding for free-range dairy cows: freedom of locomotion, social contacts, conditions for having a rest and available symptoms of discomfort. Data from the study conducted during the winter, showed that at ambient temperatures less than -5 °C, the basic behavioural activities, characterizing the status of comfort were within the norm. The cows used mostly yard (iFA=0,79038), less – boxes (iFA=0,16412) and the least – paths (iFA=0,04550). A seasonal effect is found of using the boxes for rest and rumination and reducing the time for these activities in the yard. Be confirmed in previous studies identified two behavioral phenomenon – a very early start of ruminating – immediately after eating, and increased rumination in standing position, not only on the yard but also on the paths and the entrance of the milking parlour immediately before the start of milking. Using a 4-grade scale for evaluation, based on 4 spheres of biological requirement satisfaction, it is concluded that housing conditions applied in the family dairy farm “Land O’Lake” in the town of Nova Zagora, has achieved a high degree (good grade) of biological requirements satisfaction, due to: provided possibilities for loose movement and free choice of all behavioural activitiesleading to over 82% efficiency in use of the areas of the building; solid hierarchy is built in the groups which results in lack of conflicts; provided time and place for
rest and ruminating; lack of any symptoms of discomfort.
І. Varlyakov, T. Slavov, N. Grigorova