The effect of three levels of Fermacto feeding on egg production, general metabolic state and health of the laying hens was observed by determining the functional and morphological state of liver and kidneys. One hundred, 60 weeks old laying hens, were divided into four equal groups viz A through D each of 25 birds. The hens were already vaccinated. The group A was kept as a control and iii group B, C and D, the Fermacto feeding was done at a dose rate of 1gm, 2gm and 4gm per kg of feed respectively. The experiment period was 60 days. Egg production records, visceral organ: body oveight indices, gross pathological lesions of liver and kidneys, serum glucose, serum cholesterol, serum total protein and serum uric acid levels and antibody titres against Newcastle disease were determined.

The statistical analysis of egg production record showed that from 1-15th day there was no significant difference among the experimental and control groups and from day 16-30th, there was highly significant difference between the experimental and the control groups. The highest mean egg production record was achieved I n the birds of group A. There was no significant difference between the experimental and control groups from day 31-45th ,but there was a significant difference between the experimental and control groups from day 46-60th. The birds from the group B showed the highest mean egg production.

The organ: body weight index for left kidney and right kidney showed a highly significant difference between all experimental and control groups. The highest mean left kidney: body weight index was achieved in the birds of group D. Similarly the highest mean right kidney: body weight index was obtained in the birds of group C. Organ: body weight index for liver also showed a highly significant difference between control and experimental groups and the highest liver: body weight index was achieved in birds of group B. The gross pathological study of liver and kidneys revealed some non-specific gross lesions such as little changes in colour and streaks of haemorrhages in some birds of control and experimental groups. No characteristic pathological lesion was observed in liver and kidneys of birds.

The data obtained by the analysis of serum statistically indicated that the concentration of serum glucose level was significantly increased in experimental groups than that of control group. Concentration of serum cholesterol was also significantly higher in the treated groups than in control group. Concentration of serum total protein was highest in the C group. There was significant difference in the level of serum total protein of all the experimental and control groups. The serum uric acid concentration was significantly different between control and experimental groups. The uric acid concentration was highest in group A. The data obtained by the analysis of antibody titre against ND on 1st, 15th , 30th, 45th and 60th day of the experiment showed that the highest GMHI in the birds of C group which reflected the stimulation of the immune system. So, it was concluded that Fermacto feeding had no deleterious effect on general metabolic state and immune system of laying hens.