Studies On Pharmacokinetics And Redidues Of Salbutamol In Sheep

In this paper, we studied the different condition of enzymatic on determination of salbutamol in ovine urine,and then obtained the best enzymatic conditions. We also studied on the residues and depletion of salbutamol in ovine urine, plasma, hair and other body tissues including heart, liver, spleen, lungs, kidney, eye and muscle et al.. Our purpose was to offering theoretical basis and technical support for supervision of illegal use of salbutamol in sheep.Thirty sheep(male and healthy, with 30 kg BW) were randomly assigned into five groups, each group has six sheep. One group is the blank control, while the other four are treated with Salbutamol(SAL). The treatment groups were given 0.15 mg/ kg BW by oral administration once a day for 21 days. The samples of urine and plasma were collected at day one, two three, five, seven, ten, fourteen, seventeen, and twenty one(zero withdrawal day). Samples of heart, liver, spleen, lung, kidney, eye and muscle were taken from three randomly selected sheep on day seven, fourteen, twenty one(zero withdrawal day) and the withdrawal day one, two, five, seven, fourteen and twenty one.The experimental results are as the followings:(1) we found that SAL exists as a conjugated form, by adding β-glucuronidase and arylsulfatase in urine to show a higher content of SAL. This leads to the conclusion that enzyme is necessary for more accurate results of SAL in ovine urine. The ideal condition for the enzyme treatment are: 37℃, 16 h, and 60 μL β-glucuronidase and arylsulfatase.(2) The contents of SAL in urine and plasma were 1.59 ng/m L and 0.79 ng/m L, respectively, after 30 min by single-does administration. There are two residues peaks, day seven(46.17 ng/m L), day seventeen(35.38 ng/m L) in plasma samples;(3) SAL is accumulated to the highest content of 45.46 ng/g in ovine hair at withdrawal day seven, but it is eliminated very quickly, to 8.25 ng/g after withdrawal day fourteen, which is 18.15% of the peak value;(4) The ranking of SAL residues in different tissues: liver > kidney >lung > eyes > muscle > spleen > heart. The highest content of SAL in heart, liver, spleen and eye were 3.29 ng/g, 133.64 ng/g, 63.17 ng/g and 5.60 ng/g, respectively. SAL can be detected in hear after withdrawal day twenty-one day;(5) Based on the above observations, we suggested that samples of urine, plasma or hair are used for the regulatory target for animal production, while the sample of eyes is used for the regulatory target for slaughtering process. Key word:...