Abstract
The purpose of the present study was to clarify rationalized layout and appropriate dimentions of each part of the loose housing dairy facility which has a resting area equipped with free stalls (such facilities will be called “Free stall barns” for short hereafter). Twenty-eight commercial dairy farms (14 from the Hokkaido district, 10 from the Kanto-Tosan district and 4 from the Kyushu district), each raising more than 60 cows, were selected and visited by the authors. These facilities, described in the present study, may be regarded as the representative free stall barns in Japan. Each was recommended as the best functioning facility by advisors in their respective districts. We conducted measurements of the layout and structures of the barns and surveys of the utilization of those facilities. The results are summarized as follows:
1) Layout of facilities.
Regarding arrangement of stalls in the resting area of free stall barns, two rows of stalls, which were arranged along the inside of both sidewalls, were found most frequently. There were a few barns which had one, three, or four rows of stalls. About half of the barns investigated had the feed bunk inside the buildings; the other half had it outside. All milking parlors were adjoined the resting area, and most of them (78%) were adjoined at right angle to the main building. Types of stall arragement in the parlor were, for the most part, the herringbones with double-four stalls.
2) Detailed dimensions of each part of the stall.
The following dimensions were found most frequently in the barns investigated: 2, 200-2, 400mm, 1, 200-1, 250mm, 1, 000-1, 100mm and 200-300mm for stall length, stall width, height of stall partition and height of stall floor from alley level, respectively.
3) The area of each part of the barn.
The average area of the facility per head, with full intended utilization, was 12.3m2. About half of the area was occupied by the alley for cattle (27.8%) and the area for stalls (23.0%). The remaining was used for feeding, milking, holding, milk room, etc.
4) Recommendation
Standard dimensions and arrangement for a free stall barn for Japanese dairy cows (assuming about 650-700kg body weight) are recommended by the authors. Recommended dimensions for the size and shape of free stalls are: 2, 400mm×1, 200mm for size of a free stall; 1, 000mm for height of stall partition (Isolated type with two fixed poles); 250mm for height of stall floor from alley level. Most appropriate arrangements and area are: Two rows of stalls arranged along the inside of both sidewalls; The milking palor of herring-bone type adjoined at right angle to the main building; Between 12m2 and 13m2 per head for total area of the barn.
