Cobalt content of Waikato pastures

Authors: Dewes HF
Publication: New Zealand Veterinary Journal, Volume 32, Issue 6, pp 96-97, Jun 1984
Publisher: Taylor and Francis

Animal type: Livestock
Subject Terms: Cobalt/vitamin B12, Trace elements, Diet/rations/food, Nutrition/metabolism, Pasture/crop, Vitamins
Article class: Correspondence

---

Abstract: In 1982 the author requested that cobalt be included in a series of analyses of plant leaf tissue samples submitted to the Plant Analysis Laboratory, Ruakura Plant and Soil Research Station. Samples were taken from 92 sites on 39 properties adjacent to Hamilton. All samples were carefully collected and submitted unwashed. Cobalt containing fertilizers had not been applied by any of the present owners. For this district very little information on cobalt has been released, most having been published in 1938. Yet many Waikato soils are derived from Taupo ash showers either as alluviums or as a mantle of ash that covered parent rock. In this study, iron values were used as an indicator of soil contamination. If there is any correlation between cobalt and iron values in plant leaf grown on various soils in this district, then by ingesting soil one way or another, animals would acquire extra cobalt. Cobalt determinations were made by graphite furnace-atomic absorption spectroscopy following digestion of plant material bv nitric and perchloric acid, soils from which pastures were gathered are classified as: Hamilton Clay Loam, strongly weathered tephra; Mairoa Ash (as Hamilton Clay or admixed rhyolitic-andersitic showers): Horotiu Soils, deep friable yellow-brown loams developed on rhyolitic alluvium with some admixed tephra-derived alluvium…

---