AVAILABILITY OF MINERALS IN FORAGES FOR RUMINANTS

Problem opskrbljenosti preživača mineralima vrlo je usko vezan uz njihov sadržaj, topivost i iskorištenje iz voluminozne krme. Kompleksnost problema usmjeruje istraživanja u specifične interakcije tla - biljke i životinje s posebnim osvrtom na hranidbeno i zdravstveno stanje preživača, vodeći računa o proizvodnim učincima, te reprodukciji. Dat je osvrt na čimbenike o kojima ovisi opskrbljenost biljaka mineralima iz tla, te moguća prisutnost sekundarnih spojeva koji mogu utjecati na ukusnost biljke, odnosno reproduktivno-proizvodna svojstva životinje (glukozinolati, tanin). lskoristivost minerala povezuje se sa sadržajem i oblikom u kojem su zastupljeni u biljci, o čemu ovisi probavljivost i iskoristivost hrane. Navode se podaci prema kojima dovoljna opskrbljenost voluminozne krme na pojedinim elementima nije dovoljna garancija pravilne opskrbljenosti životinje.The problem of supplementation of ruminants with minerals is the tight connection with the amount, solubility of minerals from rough forages. Complexity of the problem directs the examinations to specific interaction soil - plant - animal connected to nutritional and health condition of the ruminants, their productivity and reproductional status. The review the factors affecting supplementation of plants with minerals from the soil is given, as well as possibility of presance of secondary compound that can affect taste of the plant or performance of the animal (glucosynolate, tannin). Usability of minerals is connected to the amount and form of their prosance in the plant what affects digestibility and usability of feed. The data given in this review suggest the satisfactory supplementation of forages with minerals does not guarantee correct supplementation of the animal