Copper complexes in grassland herbage

Abstract

for suggesting this problem, and for his valuable advice and encouragement throughout the investigation. I also wish to thank Dr V. Cosslett for granting me the facilities of the electron microscope atthe Cavendish Laboratory, UniversityofCambridge, and Mr R. Home for taking the electron micrographs. This work was carried out while holding a Travelling Scholarship awarded by the Gowrie Scholarship Trust of Australia. My thanks are also due to the N.S.W. Milk Board for some financial assistance.

Availability of minerals in foods of plant origin

“…T h e small and stable copper citrate complex, however, was least affected in the rate of diffusion by additional complex-forming agents and could be absorbed most efficiently. These results partly agree with experiments of Mills (1954Mills ( , 1956 who found an increased rate of Cu absorption after giving organic complexing agents from herbage extracts with high constants of Cu association. The results of Havinga & Bykerk (1947) and of Schreier et al (1957) may also be interpreted in this way.…”

Effects of Foliar Application of Copper Sulphate on the Copper Content and Yield of Hay

“…Risk of toxicity. The possibility of danger to livestock, particularly sheep, from grazing the aftermath of areas treated with CUSO4, at the levels used in these experiments seems remote as in most cases the concentration of Cu in the aftermath was within the normal range of 5 to 20 ppm (1,6), within 4 weeks of harvesting the hay crop. The only exception was a mean value of 32-2 ppm in Experiment 2 and this was following an exceptionally high concentration (245 ppm) in the hay crop; the probability is that following a further defoliation this too would have been within the normal range.…”