A total of 156 serum samples were collected from adult ewes and goats (78 animals per each species) for serological identification of brucellosis and mycotoxicosis through a study in Kaleubia province. Forty-seven feed-mixtures (concentrates), and forty-three Maize samples were collected from localities of brucella infected sheep and goat. The feed samples were used for extraction and measurement of different mycotoxins. The mycotoxins were identified and measured in serum of brucella infected and non-infected animals. One month after parturition or abortion, twenty animals from each species were divided into four equal groups as follows: the first group was the control animals, the second group was non-infected but naturally mycotoxin poisoned animals, the third group was brucella infected animals and the fourth group was both brucella infected and mycotoxin poisoned animals. The serum biochemical, hormonal and protein electrophoretical studies were carried out. Results revealed that Aflatoxin-B1 (AFB1), Ochratoxin-A (OA) and Fumonisin-Bl (FB1) mycotoxins were identified and measured in feed, but AFB1 and OA could only be identified in the serum samples. The mycotoxins were detected in 82.6 % of brucella Infected animals, and in 10% of non-infected animals. In either mycotoxin poisoned and /or brucella infected animals, there was a significant decrease in serum prolactin levels. In non-infected animals, the mycotoxicosis induced non-significant increase of the the progesterone hormone. The triiodothyronine (T3) and the thyroxin (T4) hormones were significantly increased in serum of most ewes and goat groups. The mycotoxicosis induced significant hyperalpha-globulinemia and hypo-beta — globulinemia. in non —infected animals than control. Mycotoxicosis induced hypogamma —globulinemia in goats. In most cases, mycotoxicosis and/or brucellosis induced hyperbilirubinemia, hyperlipedemia and significant increase of ALT-enzyme activity than control. In many cases, the mycotoxicosis, unless induced significant biochemical changes alone, induced such significant changes specially with brucellosis. Based on our study, we could suggest that the mycotoxicosis may perform a predisposing stress and immunosuppressive factor for brucellosis. Also, mycotoxicosis and/or brucellosis may induce serum biochemical endocrinological, metabolic, hepatic and reproductive disturbances in ewes and goats.