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Three thyroidectomized sheep were infused intravenously with porcine calcitonin at a rate of 30 mi.u./h per kg and three sham-operated sheep were infused with vehicle for 5 h. Saliva was collected from the left parotid duct by cannulation for 10 min in every hour. Salivary secretion rates were not changed in either thyroidectomized or sham-operated sheep throughout the experiment. Before the infusion, salivary phosphorus excretion was less in thyroidectomized sheep than in sham-operated animals. Calcitonin infusion increased salivary phosphorus excretion and decreased serum phosphorus concentrations in thyroidectomized sheep. Vehicle infusion did not affect salivary phosphorus excretion in sham-operated sheep. Serum concentrations and salivary excretion of calcium were decreased by calcitonin infusion into thyroidectomized sheep but were not changed in sham-operated sheep infused with vehicle. Calcitonin infusion increased serum parathyroid hormone concentrations in thyroidectomized sheep after the decrease of serum calcium concentrations. However, vehicle infusion did not affect serum parathyroid hormone concentrations in sham-operated sheep. There was little change of cyclic AMP excretion during the experiment in either thyroidectomized or sham-operated sheep. It is concluded that calcitonin increases salivary phosphorus excretion in sheep.J. Endocr.(1984) 102, 365–368

The a.c. conductivities along the c axis of caesium nitrate have been measured in the frequency range from 3 Hz to 100 kHz at temperatures between room temperature and 274·3°C. The a.c. conductivities show a different frequency dependence in the phases II and I. The temperature dependence of the conductivities shows a discontinuous jump, on increasing the temperature, at the structural phase transition point.

Three feeding trials were conducted with beef cattle in which a combination of supplemental vitamin E and K to a no-hay finishing ration resulted in superior performance. The vitamin supplemented cattle averaged 9% faster liveweight gains and improved feed conversion. A fourth cattle feeding trial was conducted in which supplemental selenium was added to a similar finishing cattle ration. The liveweight gain response from selenium was fully as high or higher than the responses obtained with supplemental vitamins. Also, supplemental selenium, as well as supplemental vitamin A, exerted a sparing action upon liver vitamin E. The possible importance of these results and some of the limitations in interpreting them in feeding practice were discussed.