The effects of abomasal infusions of glucose or casein on milk yield and on some blood constituents of dairy cows in early and late lactations

Abomasal infusion of casein has been shown to increase the milk yield, fat yield, protein content and protein yield while no clear-cut effects were observed with infusion of glucose (Ørskov, Grubb and Kay, 1977 and confirmed by Oldham, Bines and MacRae, 1983). Little information is available about the changes in blood parameters with abomasal infusion of glucose or casein. The objective of the present experiments was to relate changes in milk production to blood parameters in dairy cows given casein or glucose as an infusion into the abomasum during early or late lactation.