The gestation period is 270-80 days. There is normally a single offspring which is nursed for 9 months. It still is found in scattered areas from India to Indochina and the Malay Peninsula but has declined drastically through hunting and habitat alteration by people and exposure to the diseases of domestic cattle. The gayal, a domestic form of gaur, is smaller than the wild animal and has shorter legs and a less prominent dorsal hump. In females and young animals the general coloration is gray, the underparts are lighter, and the chest, neck, and forelegs are darker.
Old males are a very rich, dark brown.
The lower legs are white or grayish. From the neck hangs a very long dewlap, which in old males almost reaches the ground. The tail is longer than in B. gaurus and B. javanicus and has a bushier tip. Suggestions that the kouprey is only a hybrid between B. javanicus and either B. gaurus, B. taurus, or Bubalus bubalis do not appear to be valid. There is considerable difference between the horns of the sexes.