Seasonal variation of macro and micromineral contents of some ruminant browse species from five countries in the South Pacific Region 69

Leaf samples of nine browse species, viz., breadfruit (Artocarpus altilis), calliandra (Calliandra callothyrus), dadap (Erythrina spp), gliricidia (Gliricidia sepium), fleminga (Fleminga macrophylla), leucaena (Leucaena leucocephala), sesbania (Sesbania grandiflora), mullberry (Morus alba), and vi (Spondias mombin) were collected in the dry and the rainy seasons from five countries in the South Pacific Region (Cook Islands, Fiji, Tonga, Samoa, and Vanuatu). The samples were evaluated for comparative seasonal concentration of P, K, Ca, Mg, Fe, Mn, Cu, and Zn for grazing beef cattle, dairy cattle (dry and lactating), heifers, and goats. Macro- and micro-mineral concentrations in the browse species were affected by seasonal climatic conditions. Some of the browse species had higher concentrations of macro- and micro-minerals in either the dry or rainy seasons above the requirements of specific ruminant animals. The Fe concentration in most of the browse species was higher (P < 0.05) in the dry season compared to the rainy season. The Zn concentration was extremely low in the browse species. Some browse species met the macro- and micro-mineral requirements of grazing beef cattle, dairy cattle (dry and lactating), heifers, and goats, while others could not satisfy all the mineral requirements of specific ruminant animals. The seasonal variations in the concentration of the macro- and micro-minerals suggest that in formulating and (or) supplementing rations for ruminants, both the amount of minerals in legumes and biological availability of these minerals need to be considered in the South Pacific Region.