Abstract
Liver and blood samples of three- to four-year-old steers were obtained from 15 farms located in five counties to obtain information on the mineral status of grazing cattle in the Guanacaste region of Costa Rica. Of the livers analysed, approximately 36·0, 30·7, 37·3, 33·3 and 34·7 per cent were borderline to deficient in copper, iron, manganese, selenium and zinc, respectively. Forty nine per cent of the blood samples were considered borderline to deficient in phosphorus. There was no significant difference (P>0·05) in tissue mineral concentration due to county location, with the exception of selenium. Differences (P<0·0l) in tissue concentrations among farm were found for all six tissue minerals. In general, tissue mineral could be directly related to use or absence of mineral supplements.
