SUCKLING BEHAVIOR AND FERTILITY IN BEEF-COWS ON PASTURE .1. SUCKLING BEHAVIOR

The suckling behaviour of one- to three-month-old calves, suckled by 6 6 Hereford, Simmentaler and Hereford X Simmentaler cows, was studied. The most common frequency of suckling in 24 h was 4, and the mean dura tion of each suckling event was 9.6 min. Suckling events were not even ly distributed throughout the 24-h period. Regardless of suckling freq uency or days post partum, the most common suckling period was between 04:00 and 06:00. The lowest frequency of suckling recorded was in the period from midnight to dawn. The longest interval between two suckli ng events in all cows over the 24-h period always occurred before dawn and became longer as the calf grew older (P < 0.01). Once the mating season commenced, the onset of oestrus was positively correlated (P < 0.01) with the length of the longest inter-suckling period.