[Histometric studies of functional assessment of the parathyroid glands in healthy and sick cattle]

--Weights and mean nuclear surfaces of external epithelial bodies were examined in 53 clinically intact young fattening bulls, 49 clinically intact dairy cows, 55 young fattening bulls slaughtered on account of emergency mainly for osteolamacia and rickets, and 50 cows that had died of various diseases. --Absolute parenchymal levels were found to increase along with growing age. --In young fattening bulls, epithelial bodies lost weight and nuclear surface along with severity of pathological bone changes. --Epithelial bodies in cows and young fattening bulls feeding primarily on silage were more active than those of animals feeding to a larger extent on meadow hay or kept grazing. --No signs of increased activity of epithelial bodies were recordable from animals with osteomalacia or those close to parturition. --All results so far derived from the above studies seem to suggest that, with the present regime of cattle feeding, calcium deficit or phosphate excess are not involved in the development of skeletal diseases. The findings so far obtained in the context of epithelial bodies have confirmed the contrary to the effect that calcium excess and phosphate deficit have remained to be the major causes of skeletal diseases.