Summary:-Poultry breeding has an economical importance as poultry is considered a good source of animal protein allover the world. The present study was conducted to evaluate the efficacy of allopurinol 40 mg/kg.B.wt and/or dl-methionine 6g/kg.feed on expExperimental design:Two hundred one day old Hubbard chicks were used in this study. Chicks were divided into 9 groups each of 20 except third group it was 40 chicks and chicks had been divided as follow:1st group: received no treatment and was considered as control.2ndgroup: received sodium bicarbonate (SB) in drinking water (20gm/L) for 3 successive days.3rd group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 10 successive days.4th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 3 successive days, then treated with allopurinol (40 mg/kg b.wt) in ration for 7 successive days.5th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 3 successive days, then treated with DL-methionine (6 g/kg diet) in ration for 7 successive days.6th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 3 successive days, then treated with acombination of allopurinol (20 mg/kg b.wt) and DL – methionine (3 g/kg diet) in ration for 7 successive days.7th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 10 successive days and treated at the same time with allopurinol (40 mg/kg b.wt) in ration for 10 successive days.8th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 10 successive days and treated at the same time with dl-methionine (6 g/kg diet) in ration for 10 successive days.9th group: received sodium bicarbonate (SB) in drinking water (20gm/L) for 10 successive days and treated at the same time with both allopurinol (20 mg/kg b.wt) and dl-methionine (3 g /kg diet) in ration for 10 successive days.Blood samples were taken on 1st, 7th and 14th day post treatment for hematological studies and another blood samples were collected to separate serum for investigation of liver and kidney functions. Kidney, liver, lung and heart specimens were collected i1) Effect on clinical symptoms:• All birds of control group (non affected – non treated) and non affected were healthy and showing no clinical symptoms throughout the experimental period.• Birds experimentally affected with visceral gout and none treated showed clinical symptoms such as depression, anorexia, and increase water intake while their feed intake was decreased and presented watery diarrhea.• Affected birds, medicated with allopurinol or dl- methionine or combination of half therapeutic dose of both drugs showed less degree of clinical symptoms comparing with affected non treated chicks.2) Effect on the mortality rate:The mortality rate was zero in non infected non treated group. Experimental affection with visceral gout (chickens exposed to sodium bicarbonate 2% for 10 days) induced 40% , whereas the mortality rate reduced to 20% in group affected with visceral gout b3) Effect on lesion scores:• All chicks of the non affected non treated (control) group were apparently normal and revealed no lesions in different organs.• Chickens experimentally affected with visceral gout and non medicated were emaciated, they showed white chalk- like deposits covering the surface of various abdominal organs as well as the heart. Kidneys were pale, irregular and with excessive enlargeme• Affected birds (received SB 2 % in water for 10 days) and at the same time medicated with allopurinol or dl- methionine or combination of half therapeutic dose of both drugs revealed less gross lesions than affected non treated group.• Affected birds (received SB 2 % in water for 3 days) and then medicated with allopurinol or dl- methionine or combination of half therapeutic dose of both drugs revealed no gross lesions in different organs.4) Effect on body weight:• Chickens experimentally affected with visceral gout (exposed to sodium bicarbonate for 3 and for 10 days in drinking water) evoked a significant decrease in body weight on 1st 7th and 14th days post treatment when compared with non affected non treated • Third group: animals were died from drowning by putting them into a water filled container.• Fourth group: animals were died from starvation by housing them individually and deprivation of food and water from rats until death.Light anesthesia with diethyl-ether was carried out before killing in the first, second and third group .Masseter, triceps and gastrocnemius muscles were existed and kept at – 40C till biochemical analysis.ATPase, Lactic acid, Nitric oxide, DNA and RNA levels were determined in the previously mentioned muscles immediately and 120min. after death or cervical dislocation.