Diet and mineral nutrition of sheep on undeveloped and developed tussock grassland

Abstract

Abstract Na, K, Ca, Mg, P, Fe, Mn, Zn, and Cu levels in the plasma of sheep set stocked on undeveloped and developed tussock grassland are given for 5 sampling dates during one season together with those for 10 plant species common on these blocks. The mean plasma Cu levels were significantly lower on the developed than on the undeveloped block, but were still within the normal range. Seasonally the plasma K and Ca levels were lowest at the November 1970 and February 1971 samplings, and P and Zn were lowest at the September 1970 sampling. The dicotyledonous plants contained higher levels of Na, Ca, Mg, and Cu than the grasses. The two native tussocks had the lowest levels. The P levels of Hieracium praealtum were lower, and the K, Mg, P, Fe, and Zn levels of Notodanthonia clavata and the Mn levels of Anthoxanthum odoratum were higher, on the developed block than on the undeveloped block. This was reversed for Mn levels in Agrostis tenuis and Fe content of A. odoratum. There were differences between sites ...