Summary
Comparative studies of the effects of Nordette® and LutoFolone® on 15-day-old chickens were performed to determine their effects on growth performance, biochemical parameters and on hormonal residues in the liver and muscle. Sixty chickens were equally divided into three groups, with 20 chickens per group. Group 1 served as the control group. Groups 2 and 3 were treated daily with Nordette® (1 mg/kg body weight) mixed in the ration and LutoFolone® (0.5 mg/kg body weight) administered orally through a bent stainless steel feeding tube, respectively, for 30 days (from the 15th to the 45th day of age). The treated groups were left for a further period of 15 days without treatment. Blood samples were collected at 45 and 60 days of age and used for biochemical studies, while liver and muscles were excised from each chicken and used to prepare tissue homogenates for an estimation of hormonal residues (oestrogen and progesterone). Both drugs caused a gain in body weight. They also significantly increased (p<0.01) several serum variables, including alanine aminotransferase (ALT) (410% and 300%), aspartate aminotransferase (AST) (277.69% and 261.90%), cholesterol (16.91% and 17.19%), creatine kinase (CK) (72.47% and 27.46%), creatinine (62.22% and 42.22%) and uric acid (85.43% and 70.86%), and reduced total proteins (54.38% and 51.28%), albumin (60.38% and 52.08%) and globulin levels (50.22% and 49.36%) for Groups 2 and 3 respectively at 30 days post administration, in comparison with the control birds. Moreover, this study exhibited a significant increase in the levels of oestrogen residues in the liver (26.17% and 70.99%) and muscle (17.50% and 43.41%) for Groups 2 and 3, respectively. This indicated that the oestrogen level was much higher in the liver than in muscle in comparison to that of the controls. However, some of these findings showed insignificant changes 15 days after ceasing the administration of hormones. Data on the biochemical parameters and residue levels obtained from these results clearly indicate that anabolic agents in chickens may carry a specific risk to public health.

Keywords
Anabolic, Biochemical parameter, Chicken, Egypt, LutoFolone®, Nordette®, Oestrogen.