The objective of this study was to compare the effects of calf starters of different starch and fibre content on the growth. blood and rumen parameters of Holstein female calves during the pre-weaning period. A total of 60 calves were divided into two groups. Group A/B was fed according to a two-phase calf nutrition system: the calves received calf starter "A" (28. https://parisnaturalfoodes.shop/product-category/soy-free-butter-spread/