الفهرس | Only 14 pages are availabe for public view |
Abstract This study was conducted to determine the effects of heat stress on actual received dose of water soluble tylosin in broilers. Forty Hubbard chicks were raised then divided when they reached 30 days in to two equal groups, one of them was kept under a comfortable temperature (24.1± 0.3 °C) as control group while the other was exposed to heat stress (35.6 ± 0.3 °C) for seven days (period of water medication) and till the end of taking samples. All birds received tylosin in a dose 1 gm/2 liter drinking water (equivalent to 15 mg/ kg body weight) for 3 days during heat management. Then 5 birds were slaughtered daily from each group for tylosin residues assaying in serum and tissue samples (breast muscle, liver and kidney). Result showed 238-984% elevation in tylosin concentrations in heat stressed group than non-heat stressed group. Consequently, the tylosin could be detected in heatstressed broilers at 4 days post last dosing compared with 3 days in non heatstressed group. This study recommends putting the seasonal changes in climate temperature into consideration when water is used to deliver the medicine (tylosin)in non-heat controlled poultry farms, especially in tropical and sub-tropical countries. |