Within the Core Organic Cofund project ProYoungStock, an experimental multi-site study was performed to investigate the effects of an increased level of milk feeding (10-12 l/d, ≈ 14-16% milk per body weight, enhanced milk feeding, EMF) compared to common milk feeding (6-8 l/d, ≈ 10-12% milk per body weight, restricted milk feeding, RMF). Data from 10 organic dairy farms, originally applying RMF by bucket-feeding in Austria (dual-purpose breed Fleckvieh; 4 farms) or Germany (Holstein Friesian, partly crossed with other dairy breeds; 6 farms) were analysed concerning calf welfare including health. Per farm, 6-14 female rearing calves were randomly allocated to the two feeding treatments RMF and EMF, which were applied over the milk feeding period of 13 weeks. Assessments of welfare were carried out during the milk feeding period in weeks of life 3/4, 7/8, 11/12 (±2 days) as well as after weaning in about week 15/16. Farm visits took place from October 2018 to April 2020. Welfare measures related to behaviour, observed from video recordings (manipulating other calves, manipulating objects, vocalization, duration of feeding solid feed), to health (clinical scoring during farm visits), and to performance (weight gain). Preliminary results showed that EMF led to higher weights and daily weight gains in rearing calves, especially in Austrian Fleckvieh calves. Manipulating objects was not related to milk amounts but to the feeding duration of solid feed. Analyses are still in progress; final results will be presented at the congress.