Pharmacokinetics of sparfloxacin in broiler chicken

1. The pharmacokinetics of sparfloxacin in broiler chicken was investigated following a single intravenous dose of 10 mg/kg and a single oral dose of 20 mg/kg. The pharmacokinetic parameters (AUC(0-24) or C(max)) were integrated with the pharmacodynamic parameter (MIC(90)) to optimize sparfloxacin dosage in chicken. 2. The apparent volume of distribution, total body clearance, mean residence time and elimination half-life following oral administration were 2.411/kg, 4.55 ml/min per kg, 10.54 and 5.94 h, respectively. Oral bioavailability was 61.7%. 3. Sparfloxacin was found to possess clinically useful pharmacokinetic properties. Based on pharmacokinetic/pharmacodynamic integration an oral dose of 20 mg/kg sparfloxacin for every 24 h might be recommended for a successful clinical effect in chickens.     

复方氧氟沙星注射液在猪体内的药代动力学

为测定复方氧氟沙星注射液中主药氧氟沙星在猪体内的药代动力学,同时考察复方氧氟沙星注射液中另一成分鱼腥草素钠对主药氧氟沙星的药代动力学的影响。本研究在分别给2组受试猪肌内注射复方氧氟沙星注射液和氧氟沙星注射液后,用HPLC分析血浆中的药物浓度,用MCPKP软件计算药代动力学参数。结果表明,2组猪在肌内注射复方氧氟沙星注射液和氧氟沙星注射液后的血药浓度和药代动力学参数无显著性差异,达到最大血药浓度和维持的时间接近,达峰时间约0.75 h,Cmax分别为（4.863±0.305）mg·L^-1和（5.128±0.306）mg·L^-1,t1/2β分别为（17.974±14.644）h和（23.789±29.902）h,AUC分别为（33.639±2.171）mg·L·h^-1和（36.867±4.253）mg·L·h^-1,Vd分别为1.3641、.316 L·kg^-1。说明复方氧氟沙星注射液中另一成分鱼腥草素钠对复方氧氟沙星注射液中氧氟沙星的药代动力学无明显影响。     

Pharmacokinetics and relative bioavailability of tiamulin in broiler chicken as influenced by different routes of administration

The bioavailability and pharmacokinetic disposition of tiamulin in broiler chicken were investigated after administration through the crop, drinking water, and feed at 40 mg/kg body weight. Residues of tiamulin in tissues of broiler chicken were also assessed. Plasma and tissue concentrations of tiamulin were analyzed by reverse‐phase high‐performance liquid chromatography (HPLC) method. Plasma concentration–time data were described by the non‐compartmental model for all three routes, and pharmacokinetic parameters were calculated. There were no significant differences (p > 0.05) in pharmacokinetic parameters and mean plasma concentrations of tiamulin between three routes tested (crop, water, and feed), indicating equal efficacy. Tiamulin residues in edible tissues (muscles, skin, and fat) were lower than the advocated maximum residue limit (MRL of 0.1 µg/g and that of liver was 1 µg/g) on the 3rd day. No traces were found on the 5th day after drug administration. This indicated that the withdrawal period (less than 5 days) is very short, which makes it safer. This study shows that tiamulin can be used with equal efficacy through all routes of administration in broiler chicken (crop, water, and feed).     

Polymelia in a broiler chicken

A polymelus monster was observed in a 7-week-old slaughterhouse chicken. The supernumerary limbs were smaller than the normal appendages but contained an equal number of digits.     

Pharmacokinetics of butorphanol in broiler chickens

Butorphanol tartrate (2 mg/kg) was injected intravenously in 18 healthy broiler chickens to study its pharmacokinetics. Plasma samples were analysed by a highly sensitive high-performance liquid chromatography with diode-array detection method and pharmacokinetic parameters were calculated from the mean pooled data. With non-compartmental analysis, the terminal half-life (T(1/2.z)) was 71.3 minutes, clearance was 67.6 ml/minute/kg and the apparent volume of distribution was 6.9 l/kg. The concentration-time curve was also fitted to a two-compartmental model. In this analysis, elimination half-life (T(1/2β)) was 69.3 minutes, clearance was 74.6 ml/minute/kg and volume of distribution at steady state was 5.6 l/kg. The micro rate constants k(21), k(12) and k(10) were 0.034, 0.050 and 0.029, respectively. Butorphanol was well distributed in the chickens with rapid clearance. It remained above the minimum effective concentration for analgesia in mammals for approximately two hours in the chickens.     

Pharmacokinetics of tylosin in broiler chickens

Biological availability and pharmacokinetic properties of tylosin were determined in broiler chickens after oral (p.o.) and intravenous (i.v.) administration at a dose of 10 mg/kg. The calculated bioavailability--F%, by comparing AUC values--p.o. and AUC--i.v., ranged from 30%-34%. After intravenous injection tylosin was rapidly distributed in the organism, showing elimination half-life (t1/2 beta) values of 0.52 h and distribution volume (Vd) of 0.69 L/kg, at a clearance rate (Cl) of 5.30 +/- 0.59 ml/min/kg. After oral administration, tylosin has a similar distribution volume (Vd = 0.85 L/kg), while the elimination half-life t1/2 beta of 2.07 h was four times bigger than after i.v. administration at Cl = 4.40 +/- 0.27 ml/min/kg. The obtained value tmax = 1.5 h for tylosin after oral administration indicates that using this antibiotic with drinking water in broiler chickens is the method of choice. However, a relatively low value Cmax = 1.2 micrograms/ml after oral administration of tylosin shows that dosing of this antibiotic in broiler chickens should be higher than in other food producing animals.     

Pharmacokinetics of levamisole in broiler breeder chickens

The pharmacokinetics of levamisole was studied in 20 broiler breeder chickens (chickens that give eggs to breed broilers). A single dose of levamisole (40 mg/kg) was administered orally or intravenously to chickens before the onset of egg production, prelay (age = 22 weeks), and repeated at the peak of egg production (age = 32 weeks). A high-pressure liquid chromatographic with ultraviolet detection method (HPLC-UV) was used for quantification of levamisole in plasma. Using compartmental analysis, levamisole followed a three-compartmental open model with mean values of alpha = 0.1224 and 0.4968, beta = 0.01663 and 0.01813, gamma = 0.002 and 0.002/min at the prelay and at the peak of egg production periods, respectively. The mean values for volume of distribution at steady state (V(ss)), determined by compartmental analysis, were significantly different for prelay and peak of egg production (8.358 and 13.581 mL/kg), respectively.     

三氧化二砷在雏鸡体内的药代动力学研究

应用新银盐法研究三氧化二砷在雏鸡体内的药物代谢动力学特征。数据经MCPKP药代动力学软件分析得出:腹腔注射三氧化二砷的药时数据符合一级吸收二室模型,动力学方程为:C=1.62916 e-0.22733t+0.15327 e-0.02024t-1.78243 e-1.36943t,其主要药代动力学参数:AUC0.13459 mg.L-1.h、Cmax 1.08215 mg.L-1、Tpeak 1.64099 h、T1/2Ka0.50605 h、T1/2α3.04841 h、T1/2β34.23920 h、Ka 1.36943 h、K120.09436 h、K210.04101 h、Kel0.11220 h。     

Chondroitin sulphate distribution in broiler chicken carcasses

1. The content of chondroitin sulphate (CS), known as a nutraceutical, was estimated in broiler chicken carcasses by analysing sulphated glycosaminoglycan uronic acid in posterior sternum (keel) cartilage and bones from 4 parts (wing, leg, front and hind) of carcasses.

2. The results of the present study suggested that approximately 0.63 g CS uronic acid (or 1.9 g as CS) can be extracted from a 1.66 kg whole broiler chicken carcass. The amount of extractable CS from keel cartilage, which has been reported as a valuable source of CS in broiler chicken carcasses, was surprisingly low (<10% of total CS).     

Trace mineral interactions in broiler chicken diets

1.?The aim of the present study was to demonstrate trace mineral interactions among organic copper, iron, manganese and zinc (Cu, Fe, Mn and Zn) in broiler chickens.

2.?Three experiments were conducted using a control diet which was deficient in Cu, Fe, Mn and Zn.

3.?In experiment 1, the control diet, supplemental organic Cu, Fe alone and combined diets, were randomly fed to 4 groups of one-day-old Cobb broilers (each group had 6 replicates of 4 birds).

4.?In experiment 2, the control diet, supplemental organic Mn and Zn alone or combined with Cu, Fe diets and corresponding inorganic combined diet, were randomly fed to 6 groups (each group had 8 replicates of 6 birds).

5.?In experiment 3, the depletion of organic Zn, the depletion of inorganic Zn and normal Zn treatments were carried out in three groups of one-day-old Cobb broilers (each group had 8 replicates of 6 birds).

6.?Adding organic Cu, Fe and Mn alone or combined to Zn deficient diets did not significantly improve bird performance and were mostly excreted. Supplemental organic Zn alone or combined with other elements significantly increased feed intake, body weight gain and tibia bone length. However, supplemental organic Fe alone or combined with Cu significantly increased feed intake but had no obvious effect on body weight gain. The organic Fe supplementation resulted in a wider tibia.

7.?Depletion of organic and inorganic Zn resulted in decreased feed intake, body weight gain and total tibia bone Zn content. Zinc deficiency did not affect the uptake of organic Fe by tibia bone but reduced its total Fe content.

8.?Zinc is the first limiting element among these 4 trace minerals. Adding Mn, Cu and Fe to Zn deficient diets did not stimulate bird performance. Surplus organic Fe and Cu resulted in increased feed intake and increased tibia bone Fe content but did not contribute to bird performance.     

Pharmacokinetics and bioavailability of valnemulin in broiler chickens

Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap. 34 , 247–251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). Pharmacokinetic characterization was performed by non‐compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(V_z) of 4.27 ± 0.99 L /kg. Mean valnemulin t_1/2β(h), Cl_β(L /h /kg), V_ss (L /kg) and AUC_(0–∞)(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a C_max of 2.2 μg/mL achieved at 0.43 h (t_max), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple‐peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2–6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens.     

脱氢乙酸钠在肉鸡组织中的残留消除

研究脱氢乙酸钠作为饲料防霉剂在鸡组织中的残留消除,为其在鸡组织中的残留监控及休药期的制定提供理论依据。黄羽肉鸡连续饲喂200 mg/kg脱氢乙酸钠30 d后,于不同时间分别取肌肉、肝脏、肾脏和皮脂样品,采用反相高效液相色谱(HPLC)方法测定样品中脱氢乙酸钠含量。休药1 d时,鸡肾脏、肝脏、肌肉和皮脂中脱氢乙酸钠残留量分别为0.68、0.59、0.34和0.20 mg/kg。随着休药时间延长,各组织中脱氢乙酯钠的残留量逐渐降低,脱氢乙酸钠在肉鸡各组织中的残留水平依次为肾脏、肝脏、肌肉和皮脂。在组织中的残留消除半衰期分别为肾脏5.86 d、肝脏6.02 d、肌肉8.88 d及皮脂为10.38 d。若以0.2 mg/kg为临时最大残留限量(MRLs),则脱氢乙酸钠在鸡不同组织中的休药期分别为肾脏12.37d、肌肉9.37 d、肝脏9.18 d、皮脂4.16 d。得出结论:200 mg/kg脱氢乙酸钠拌料饲喂肉鸡30 d,在肉鸡各组织中的残留水平较低,均低于0.7 mg/kg;残留消除相对较快。     

The radiation pasteurisation of broiler chicken carcasses

Irradiation of standard broiler carcasses within 24 hr. of slaughter with a dose of 0.15 Mrad of gamma radiation was sufficient to give a shelf life of more than six days at 5° C. followed by one day at 15° C. The carcasses were treated and stored in air and remained unchanged in appearance and odour. After cooking, treated and stored carcasses were indistinguishable, when tasted in blind comparison tests, from un‐irradiated material held at —20° C. for the same time. The storage conditions chosen were taken to represent the upper limits of commercial and domestic handling during distribution of unfrozen broiler chicken. The economics of the radiation process are discussed.     

Pharmacokinetics and oral bioavailability of pentoxyfylline in broiler chickens

The pharmacokinetic properties of pentoxyfylline and its metabolites were determined in healthy chickens after single intravenous and oral dosage of 100 mg/kg pentoxyfylline. Plasma concentrations of pentoxyfylline and its metabolites were determined by a validated high-performance liquid chromatographic method. After intravenous (i.v.) and oral (p.o.) administration, the plasma concentration-time curves were best described by a one-compartment open model. The mean elimination half-life (t(1/2el)) of pentoxyfylline was 1.05 h, total body clearance 1.90 L/h x kg, volume of distribution 2.40 L/kg and the mean residence time was 2.73 h, after i.v. administration. After oral dosing, mean maximal plasma concentration of pentoxyfylline was 4.01 microg/mL and the interval from p.o. administration until maximum concentration was 1.15 h. The mean oral bioavailability was found to be 28.2%. Metabolites I, IV and V were present in chicken plasma after both i.v. and p.o. administration, with metabolite V being the most dominant.     

Dioxin residues in the edible tissue of broiler chicken

The aim of this study was to determine the contamination of broiler chicken with polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) after feeding either uncontaminated feed or feed contaminated with 1, 2 or 4 ng/kg toxic equivalents (TEQ). The feed was mixed with pure substances of PCDD/Fs to get the intended contamination. Ten groups of seven 1-day-old chickens each were housed in special cages for broiler fattening. The fattening period lasted for 6 weeks. The contaminated feed was given for either 2, 4, or 6 weeks, one group received uncontaminated feed (control group). After slaughtering the edible parts of the chickens breast and leg including the skin were homogenized. Body weight gain and feed conversion (kg feed/kg body weight gain) were in the normal range (final weight 1.98+/-0.07 kg; feed conversion 1.74+/-0.03). One kilogram edible tissue contained an average of 21.2+/-4.1% of the total TEQ-intake in all groups. The PCDD/Fs residues in the edible tissues significantly correlated with the amount of PCDD/Fs-intake (r=0.99; Pearson correlation). There was no decrease in dioxin residues (% of total PCDD/Fs intake) after a 2 or 4 weeks withdrawal period. The results of this trial predict that a threshold value of 2 pg/g chicken fat can be met if the PCDD/Fs content in chicken feed is not higher than 0.4 ng/kg.     

Accumulation of lipofuscin in broiler chicken with wooden breast

Lipofuscin is one of the indicators of oxidative stress. To elucidate the role of oxidative stress in the development of wooden breast, this study investigates lipofuscin accumulation in various parts of wooden breast muscles. Sampling was performed using 46-day-old broiler chickens housed at a commercial Japanese poultry slaughterhouse. Fourteen wooden breast fillets and 13 normal breast fillets were collected in the deboning line. The samples used to measure shear force, 2-thiobarbituric acid reactive substance (TBARS), and for histological analysis were taken from the six portions of breast muscle fillets. In muscles affected by wooden breast, vacuolated muscle fibers were observed, and connective tissues appearing like perimysium were expanded with fibrosis. TBARS value and accumulation of lipofuscin were significantly higher in the wooden breast than in the normal breasts. A lot of lipofuscin granules were localized in the cytoplasm of collapsed muscle fibers of the wooden breast. The cranial portion of the wooden breast showed the highest shear force. The cranial position had a large amount of connective tissue and lipofuscin granules. The results of the present study strongly suggest that high oxidative stress, especially with a significant accumulation of lipofuscin, is associated with the development of wooden breasts.