Cobalt/vitamin B12 deficiency in sheep [OWLD, Ovine white liver diseases]

abonos npk agneau alimentation des animaux animal feeding blood serum brebis calostro cobalt cobalto cobre colostrum copper cordero cuivre deficiencia de oligoelementos engrais npk ensilado ensilage (produit) ewes foin gain de poids ganancia de peso gramineas graminee grasses hay heno lambs liver diseases maladie du foie noruega norway npk fertilizers oveja pastizales pastures silage symptome symptoms trace element deficiencies vitamin b12 vitamina b12 vitamine b12 weight gain