THE BORDERLINE OF BREEDING DAIRY ANIMALS FROM A PHYSIOLOGICAL POINT-OF-VIEW

The main problems of dairy husbandry, such as metabolic disturbances, impaired fertility and udder and claw diseases, indicate that physiolo gical limits have been reached or have been partially exceeded. The re gulation of feed intake, rumen metabolism and regulation of intermedia te metabolism may serve as examples of the upper-physiological limits of milk production. The main problem Is characterised by the gap betwe en generically based needs and the metabolic or management conditions. Selection for flat lactation curves and longevity has to be intensifi ed.