Abstract. Forty Thai x Holstein-Friesian (HF) crossbred dairy cows (75 % and 87.5 % HF upgrade level) with calves were used in experiments to investigate restricted suckling (RS) versus bucket rearing (BR) and hand versus machine milking in Thailand.

Calves were kept indoors and remained with their dams during the first 4 days and were then allocated to the RS or BS treatment. Milking was done twice daily and RS-calves were allowed to suckle for 15 minutes after milking. All experimental animals were fed according to requirements with concentrate supplements, minerals and water ad lib.

This paper reports effects on reproductive performance and weight of cows.

Calving to first oestrus interval in cows with RS and BR calves were 72.2 ± 2.5 and 54.7 ± 2.5 (p < 0.001), respectively, and days open 114.2 ± 6.68 and 86.5 ± 6.7 (p < 0.01).

Milking method (hand or machine) had no effect on days to first oestrus and days open. Primiparous cows had a longer calving to first oestrus interval than multiparous cows (p < 0.001) (72.3 ± 2.8 vs 54.5 ± 2.3) and a longer days open period (p < 0.01) (114.4 ± 7.4 vs 86.2 ± 6.1).

Body weight change of cows during the first 2 months of lactation was not affected by any treatment or systematic factor tested.