Oxytetracycline (OTC) is administered frequently in veterinary field for the treatment of infectious diseases in large animals and small animals and in the birds. 11 is readily absorbed from the intestine by most mammals but intestinal absorption in poultry is restricted. This project was designed to get more beneficial effect of oxytetracycline in poultry by adding some potentiating substances like citric acid, terephthalic acid and calcium sulphate in the diet.
For this purpose 100 day old chicks were purchased from the local market. These were reared in the poultry house in the College of Veterinary Sciences, Lahore. They were provided self prepared poultry ration and water ad-lihilum for three weeks. After three weeks these birds were randomly divided into five groups A, B, C, 0 and E comprising twenty birds each. Five (lilferent experimental rations were fed for one week to each group. Group. "A" was given the ration without oxytetracycIine and was kept as control. Group "B" was given the ration with 200mg oxytetracycline per kg of ration. Similarly Group "C" was given the ration with 200mg OTC and 200mg citric acid per kg of ration. Group "I.)" and "F" were fed on ration with 5.9gm terephthalic acid (0.59%) +200mg OTC per kg of ration and 8 gm calcium sulphate (8.0%) + 200mg OTC per kg of ration respectively. The blood samples were collected at 1st, 3rd and 7th day of treatment and serum concentration of oxytetracycline was measured by using the agar well diffusion method with Bacillus subtilis using as test organism. rllhe average values of concentration of OTC in serum of group, B were 0.807±0.56, 0.897±0.63 and 0.886±0.64 on 1st, 3rd and 7th day, which indicated increase from
3rd to 7th was not significant. In group "C" the average values of OTC concentration in serum were 1.366±0.66, 1.767±0.62 and 1.657±0.67 on 1st, 3rd and 7th day respectively, which indicated that citric acid had immediate potentiating affect when mixed with oxytetracycline. however, this effect remained constant during further days of treatment. Similarly the blood serum level of OTC in group I) and E was also increased by TPA and calcium sulphate used a potentiating agents. however, these agents are not SO effective primarily as citric acid in group C.
The result of the present study suggest that oxytetracycline concentration remains constant during all the days of treatment if it is supplemented alone in ration. however, in the presence of other drugs or salts used alongwith it as potentiating agents its concentration in the blood varies according to the nature of the drug or salt incorporated.