Isikhumba sezimvu siyisikhumba sembuzi noma sezimvu zomndeni wakwaBovidae.Isikhumba sembuzi noma semvu siqukethe amanzi, amaprotheni, amafutha kanye nezinto ezingaphili, lezi zinto ezimbili zokugcina zincane kakhulu, i-protein ekhishwe kungqimba lwe-epidermis ngokuyinhloko i-keratin; i-Dermis, ikakhulukazi. i-collagen kanye ne-net hard protein, ngaphezu kwalokho isaqukethe amaprotheni aqinile, i-albumin, i-globulin ne-mucin.