D. Dimov1*, Ch. Miteva1, Zh. Gergovska2

1Department of Applied Ecology and Animal Hygiene, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria. 2Department of Animal Science – Ruminants and Dairy Farming, Faculty of Agriculture, Trakia University, 6000 Stara Zagora, Bulgaria.

Abstract. The study was conducted at 3 cattle farms within three regions of Southern Bulgaria – Stara Zagora, Haskovo and Plovdiv. At all three farms, rearing of the cows was in free groups with individual rest cubicles in within a semi-open building. The daily regimen was different. At the three farms, the separate technological elements of the cubicles were different with the exception of the neck rail height, which was the same – 120 cm. The cubicle flooring was also different (2.14 m2, 2.31 m2 and 2.37 m2), as well as the bedding usage (straw mixed with composted manure, rubber mat and straw + composted manure). There was a significant influence of the farm and the season on the three comfort indices of cows (cow comfort index (CCI), stall usage index (CUI), stall standing index (SSI)). A significant effect of the hour of measurement was found only in the SUI. The small distance between the front of the cubicle and the neck rail (21 cm), and between the rear of the cubicle and the neck rail (140 cm) led to lower values of CCI (65.46% and 66.37%) and SUI (44.51% and 37.46%), as well as high values of SSI (17.52% and 13.35%). The type of the used bedding also had an influence – these indices had the highest values when the bedding was straw mixed with composted manure, instead of a rubber mat. The larger distance from the neck rail to the front of the cubicle (65 cm), the optimal distance from the neck rail to the rear of the cubicle (150 cm) and a soft bedding of straw mixed with composted manure provided better comfort to the cows, respectively CCI – 78.43%, SUI – 54.34% and SSI – 9.83%. Season had a significant influence on the values of the comfort indices, with lower values of CCI and SUI and higher values of SSI in the summer months, compared to the autumn. The feeding regimen and the milkings number also affected the comfort indices of dairy cows. Their evaluation must be conducted in accordance with the specific farm’s regimen.