Presence of antibiotic residue and residual effect of tylosin tartrate in broiler

This study was designed with the aim to determine the impact of residual antibiotics on poultry muscle (breast and thigh), kidney, spleen, fat and liver and effects of discriminate and indiscriminate use of antibiotic on haematological constituents in broiler chickens. The chickens were properly reared and on the day of 16, chicks were randomly divided into three groups namely control group (group A), discriminate antibiotic group (group B) and indiscriminate antibiotic group (group C). In case of discriminate group, the chicks were treated with antibiotics followed by withdrawal period of one week before the sacrifice of the birds. On the other hand, indiscriminate group of the chicks was continued without giving any withdrawal period and birds were sacrificed for sampling. Thin Layer Chromatography method was used for screening ‍and detection of tylosin tartrate residues in poultry tissues. The samples were extracted with trichloroacetic acid (30%), diethyl ether, followed by detection inpre-coated thin layer chromatography paper on ultraviolet detector. In case of group B, the residue of tylosin was 100% in livers, 83.33% in kidneys, 0% in thigh muscles, and 16.67% in breast muscles, 33.33% in fat and 16.67% in spleen. In case of group C, the residues of tylosin were 100% in livers, 100% in kidneys, 0% in thigh muscles, and 33.33%in breast muscles, 50% in fat and 33.34% in spleen. Among the poultry tissues, liver and kidney had the highest level of antibiotic residues in comparison to other samples. Tylosin antibiotic showed some changes in hematological parameters of broiler. The Hb and TEC content were significantly decreased at 31^stday of tylosin treatment at recommended dose compared to untreated control. But percent PCV was slightly decreased. There was significantly increased live weight gain of broiler from day 16^th to day 28^th compare to untreated control. However, there was no significant difference among the groups in gaining live weight at 31^st day. The study concluded that once antibiotics are administered to broiler, antibiotic residues are present in high or low concentrations in their products which mainly depend on the duration of the administration of antibiotics. After the administration of antibiotics, concentration of their residues gradually reduces in meat & other meat products and mostly after 4-5 days of administration excretion of residues is negligible