Milk samples from 60 dairy she-goats were collected from Oseim locality. Among these she-goats some showed clinical mastitis and the others were clinically sound. Investigation by Ring test (A.B.R.T.) for brucellosis was done on all milk samples collected and showed negative results. California mastitis test (CMT) and white side test (W.S.T.) were carried out to detect the subclinical mastitic cases were 10 (8.3%) and 22 (18.3%) owing to the
infection being single or double and ended with triple variably. Isolation and identification of the bacterial aetiological agents was carried out on mastitic samples. The isolated organisms were Staph.aureus, Strept.agalactiae, Strept.dysgalactiae, Strept. uberis, E.coli and C.pyogenes. These microorganisms were single or double and triple causative agents. Antibiotic sensitivity tests showed variable potency between high, moderate and slight effect by measuring the inhibition zones. Finally from these studies, the recommended products to use for treatment of these mastitic cases were tetracycline and chloramphenicol.