Blood Concentration Determination And Practicability Evaluation Of Typical Antibiotics In Pigs

Antibiotics are compounds with the ability to kill or inhibit the growth and reproduction of microorganisms,which are mainly produced by fungi,bacteria and actinomycetes or synthesized by chemical methods.The discovery and application of penicillin in the 1940s made antibiotics quickly become the main means of fighting bacterial infections,and widely used in the medical,agricultural,animal husbandry and food industries.Antibiotics occupy a large proportion in veterinary medicine,In order to compare the effectiveness of veterinary antibiotics produced by different manufacturers in veterinary clin,ical practice,in this study,cefotaxime suspension injection,florfenicol injection,doxycycline hydrochloride soluble powder,Florfenicol Premix,Tilmicosin Premix,Taiwanmycin tartrate premix and compound amoxicillin powder produced by different manufacturers were used as the experimental drugs,to carry out its blood drug concentration detection in pigs and palatability of pig evaluation,with the result of the experiment were analyzed,it provides some reference basis for pig enterprises and pig farmers to use medicine rationally and effectively in veterinary clinic.The experimental animals were healthy Duroc×Landrace×Yorg hybrid nursery pigs with a body weight of about 20±5 kg.Ceftiofur suspension injection and florfenicol injection were given intramuscular injection.Blood samples were collected from the vena cava at 0 h（before injection）,12 h,24h,36 h,48 h,72 h,96 h,120 h and 0 h（before injection）,2 h,12 h,24 h,36 h,48 h that after administration,respectively.Plasma samples were detected by high performance liquid chromatography combined with mass spectrometry and quantified by external standard method.The main pharmacokinetic parameters:AUC,C_max,T_maxand T_1/2were calculated by<<Win Nonlin 5.2.1>>,contrast and analyze,select the more reasonable and effective ones.Doxycycline hydrochloride soluble powder,flufenicol premix,temicocin premix,tywanmectin tartrate premix and compound amoxicillin powder were given orally for several times through mixed feeding.Blood samples were collected from the anterior vena cava at seven time points:0 h（before experimental administration）,3 h（3 h after the first day of administration）,24 h（before the second day of administration）,27 h（3 h after the second day of administration）,48 h（before the third day of administration）,51 h（3 h after the third day of administration）,72 h（24 h after the third day of administration）.Plasma samples were detected by high performance liquid chromatography combined with mass spectrometry,quantified by external standard method,and the plasma concentration-time curve was drawn.At the same time,the palatability test of mixed oral drugs was carried out,and the combination time curve and palatability analysis were carried out to select the more reasonable and effective drugs.The optimized method is specific,sensitive and can be used to determine the content of the same antibiotics in pig plasma from different manufacturers.The results showed that the effect of the same antibiotics produced by different factories on pigs was different.The main pharmacokinetics parameters AUC and Cmax were significantly different among the tested antibiotics from different manufacturers,and there were statistical differences among individuals,and the effect of the antibiotics produced by the factories generally accepted by the farmers was more significant and the cost of the antibiotics used was not different.In the breeding process,the choice of antibiotics recommended by the public recognition and some well-known manufacturers,can reduce the risk of breeding to a greater extent.