Stalls of three different lengths 160, 170 and 180 cm with width being 130 cm in each case were used for an experiment. Each was provided with a urine-feces mixed type gutter with a slotted cover.
Six milking cows (Holstein) varying in body size were kept in each of these stalls for three days observation with regard to cleanliness of cows udder and time required for udder preparation.
    Dirtiness of the udder and udder preparation time increase with decreasing cow body weight when the stall length was fixed, and with stall length when cow body size was fixed. The results indicated that stall length should be 1.3 cm longer for every additional 10 kg cow body weight when the udder preparation time was fixed. This value is much more than that published standard dairy barn construction which bases at all length on cow body weight.
Standard values should thus be redetermined so that udder preparation time will be uniform and this in turn may lead to greater routine work efficiency.