Effects of Testosterone Propionate Residues on Broiler Tissue and Its Effect on Body Health

The study was conducted to investigate the effects of testosterone propionate supplementation on tissues residue of broilers,and its residual effect on serum biochemical parameters,testicular growth and development of broiler chickens,to provide a basis for the protection of animal products safety. A total of 160 male 60-day-old broilers with (2.2±0.1)kg body weight were selected and assigned to control group and testosterone propionate supplementation group. The chicken in control group were fed basal diets while that in testosterone propionate supplementation group were fed diets supplemented with 20 mg/kg testosterone propionate for 7 d. The broilers was slaughtered at the day of 2,6,11 and 17 d after the testosterone propionate supplemented diets were ending. The crest,liver,testis and musle were collected to measure the testosterone propionate residues and testosterone concentration by lquid chromatograph mass spectrometer mass spectrometer (HPLC-MS/MS). The serum samples were collected from the veins to measure the serum biochemical profiles by automatic biochemical analyzer. Testis samples were collected to measure the testis cell morphology and mastocyte accounts by HE and toluidine blue staining. The results showed that:①The testosterone propionate concentration in serum was the highest,followed by the crest. However,there was no testosterone propionate residues in breast muscle,leg muscle,liver and testis. The testosterone propionate concentration in crest was not affected by the withdrawal time (P>0.05). The content of testosterone propionate at 17 d of the withdrawal time was extremely significantly lower than that of 2,6 and 11 d (P<0.01),and there was a regressive between the residues of testosterone propionate in the blood and crest and withdrawal time.②Compared with the control group,the concentration of propionate in testis at the withdrawal time of 2,6,11 and 17 d was reduced 71.45%,63.46%,62.86% and 73.61% (P<0.01),respectively.③The relative weight of testis was significantly lower at the withdrawal time of 2 d (P<0.05). But there was no significant difference in liver relative weights among the two groups in all the withdrawal time (P>0.05).④Most of serum biochemical parameters (TP,ALB,A/G,CHO,TG,LDH,ALT and AST) were not significantly affected by testosterone propionate supplementation (P>0.05).⑤Testis lose the profiles, outed of the order of spermatogenic cells in tubes by testosterone propionate supplementation. Degranulation mass cell accounts,mast cells were higher than control group. In conclusion,the testosterone propionate could result in atrophy of the rooster testis,which could be detected by blood and crest samples,and the results could provide a basis for the study of livestock products safety.     

不同光照周期对鸡睾酮合成的影响

为研究不同光照周期对公鸡睾酮合成的影响,试验选择120只20周龄体重相近的AA(爱拔益加)公鸡,随机分配到3个不同光照处理组,SD、CTR、LD组分别采用8L:16D、12.5L:11.5D、16L:8D光照周期,4周后采集血清和睾丸;用ELISA技术检测睾酮含量,用实时荧光定量PCR和Westernblot技术检测睾酮合成的3个关键酶(StAR、Cyp11a1、3β-HSD)表达量,HE染色观察睾丸中曲细精管横截面积。结果表明:睾酮含量随光照周期延长极显著增加(P<0.01),并伴随睾酮分泌关键酶StAR、Cyp11a1、和3β-HSD表达量极显著升高(P<0.01),曲细精管横截面积极显著增大(P<0.01)。综上,不同光照周期可通过影响睾酮合成3个关键酶表达而影响睾酮合成,随着光照时间延长,睾酮合成增加,睾丸生精功能增强。     

单色光对肉鸡睾丸形态结构的影响

采用LED（Light-emitting diodes）灯作为光源,比较单色光对雄性AA肉鸡睾丸形态结构的影响,并对其内在机理进行探讨。将48只刚出壳的AA肉鸡分为4个处理组,试验组为红光组（660 nm）、绿光组（560 nm）和蓝光组（480 nm）,对照组为白光组（400-760 nm）,每组12只,自由采食。光照强度为15 lx,光照制度23 h∶1 h（L：D）。49日龄利用放射免疫法检测血清中甲状腺激素和睾酮的含量,并测量体重、睾丸重、睾丸体积、曲精细管面积和生精细胞百分数。结果表明,蓝、绿光对睾丸的影响较显著,蓝、绿光组的体重、睾丸重、睾丸体积、曲精细管面积和生精细胞百分数显著高于红、白光组7.22%-32.37%（P〈0.05）,且蓝光组T3、T4和睾酮水平比其他光组高14.36%-26.20%。结果提示蓝光比其他单色光更能促进甲状腺激素和睾酮的分泌,进而影响肉鸡睾丸的形态结构。     

牛磺酸对大鼠睾丸间质细胞分泌睾酮的影响及作用机理初探

将雄性Wistar大鼠（220～250g）的睾丸间质细胞混悬液用不连续梯度（5％、30％、58％、70％）Percoll分离液分离，在细胞培养液中分别加入牛磺酸及促性腺激素（HCG）、雄烯二酮、孕酮、cAMP进行培养，用放射免疫分析方法测定作用24h后培养液中睾酮含量。结果表明，牛磺酸可使睾丸间质细胞分泌睾酮的能力显著增加；能增加HCG和cAMP诱导的睾酮分泌；能促进雄烯二酮和孕酮向睾酮的转化。牛磺酸能增加睾丸间质细胞睾酮的分泌，并可能在类固醇合成的多个环节中都起到了一定的促进作用。     

GnRH一次性主动免疫对公猪血清睾酮含量的影响

采用以促性腺激素释放激素(GnRH)并列体(GnRH-tandem)为基本结构的免疫去势苗对公猪进行一次性主动免疫。结果表明免疫组的公猪睾酮浓度极显著地低于完整组;睾丸长度极显著地小于完整组;屠宰体重明显高于完整组。因此,GnRH一次性免疫有望取代传统的外科阉割,在实际养猪生产中得到推广和应用。     

神经肽W对猪睾丸间质细胞增殖和睾酮分泌的影响

为了明确神经肽W(NPW)对猪睾丸间质细胞功能的影响,本试验采用RT-PCR和免疫荧光(IFA)技术研究了NPW受体NPBWR1(GPR7)、NPBWR2(GPR8)基因和蛋白在睾丸间质细胞的表达与分布,用MTT法和放射免疫分析(RIA)技术研究了不同浓度的NPW(NPW-30)对睾丸间质细胞增殖和睾酮分泌的影响。结果表明,NPBWR1和NPBWR2 mRNA在猪睾丸间质细胞中表达,NPBWR1在睾丸间质细胞上分布;10-6和10-8mol/L NPW处理睾丸间质细胞24 h可分别极限著或显著促进睾酮的分泌(P0.01,P0.05),10-10mol/L NPW可极显著促进睾丸间质细胞的增殖P0.01)。研究结果提示,NPW可促进猪睾丸间质细胞的增殖和睾酮的分泌,进而参与生殖的调控。     

维生素E对绵羊原代睾丸间质细胞睾酮合成的影响

本试验旨在研究维生素E对绵羊原代睾丸间质细胞睾酮合成的影响。选择2月龄杜×寒杂交公羔,屠宰后取睾丸组织。分离绵羊睾丸间质细胞,随机分为4个处理组,每个处理组3皿,培养基内添加不同浓度维生素E(0、40、80、160μg/m L)。培养结束后,测定培养基上清睾酮含量,将细胞裂解测定睾酮合成相关酶3β-羟基类固醇脱氢酶(3β-HSD)、17β-羟基类固醇脱氢酶(17β-HSD)、胆固醇侧链裂解酶(P450scc)、17α-羟化酶(CYP17)以及睾酮合成相关基因3β-HSD、17β-HSD、P450scc、CYP17、类固醇合成急性调节蛋白(St AR)基因相对表达量。结果表明:与对照组相比,添加40μg/m L维生素E有提高绵羊睾丸间质细胞睾酮分泌量的趋势(P=0.061),添加40μg/m L维生素E能显著提高P450scc和3β-HSD酶含量(P0.05),P450scc m RNA与3β-HSD m RNA相对表达量也显著提高(P0.05)。     

HPLC法检测环丙沙星在肉鸡组织中残留的研究

本文建立了检测环丙沙星在肉鸡组织中残留的高效液相色谱分析法。并利用建立的方法对环丙沙星在肉鸡体内的残留和消除规律进行了研究。每1L水中添加200mg环丙沙星,对120只肉鸡连续给药5d,使用高效液相色谱法对肌肉、肝脏和肾脏进行药物残留分析。残留结果研究表明,至体药13d时,在肝脏和肾脏中仍可检出0．015mg／kg和0．008mg／kg环丙沙星。在本试验条件下,建议环丙沙星,临床体药期为15d左右。     

C-fos对体外培养仔猪睾丸间质细胞睾酮分泌的影响

通过C-fos ASODNs诱导C-fos基因发生转录后沉默,用人绒毛膜促性腺激素(HCG)诱导体外培养的3周龄荣昌仔猪睾丸间质细胞(Leydig cells,LC)睾酮分泌,用酶联免疫分析方法检测基础状态下和HCG诱导下体外培养的仔猪睾丸间质细胞睾酮分泌的水平。结果显示,C-fos ASODNs以剂量依赖性方式抑制基础状态下和HCG诱导下的睾酮分泌(P0.01),这表明C-fos在基础状态下还是HCG诱导下均可促进仔猪睾丸间质细胞睾酮的分泌。     

盐酸沙拉沙星在肉鸡组织中的残留

建立了肉鸡组织中盐酸沙拉少星的HPLC测定方法，并测定了肉鸡单次内服（每1kg体重10mg)和连续5d混饮（每1L饮水50mg）给药后组织中的沙拉沙星残留特征。组织样品用乙腈-氨水匀浆，离心后取上清液用正已烷-乙醚除脂，水相用磷酸酸化后作HPLC检测。色谱柱为Hypersil C18柱，此外检测波长280nm。流动相为乙腈-2%西丁基溴化铵（体积比10：90），用磷酸调pH值至2.5。肝脏、肾脏、肌肉中沙拉沙星的检测限为0.05μg/g，组织样品回收率均大于90%。鸡单次内服盐酸沙拉沙星后，24h内各组织中均可检出药物，48h后肝脏、肾脏、肌肉中药物残留量均低于0.05μg/g；混饮停药后，6h内肝脏、肾脏中可检出残留药物，12h后3种组织中残留量均低于0.05μg/g。结果表明，盐酸沙拉沙星的肉鸡组织中消除迅速，连续治疗剂量用药后组织中无药物蓄积。     

丙酸睾丸酮对皖西白鹅繁殖性能和生殖激素变化的研究

利用不同浓度的丙酸睾丸酮作用于就巢第1 d的皖西白鹅鹅群进行醒抱和提高产蛋率的实验,观察和记录其就巢行为和产蛋情况,并利用时间分辨荧光测定法进行E2、PRL、P4和FSH的测定。醒抱实验结果表明:不同浓度的丙酸睾丸酮对皖西白鹅的就巢有不同的醒抱效果,其中以1.0 mL/只的醒抱效果最好,0.7 mL/只的次之,而0.4 mL/只较差。激素测定结果表明:肌注丙酸睾丸酮后,E2水平上升,PRL和P4 均下降,FSH变化不明显。这一结果提示,其醒抱效果与丙酸睾丸酮浓度呈一定的剂量依赖关系,肌注丙酸睾丸酮后皖西白鹅的生理内分泌状况向产蛋的方向发展,表明丙酸睾丸酮可以用来抑制禽类的就巢和提高其产蛋率。     

The Effect of Chromium Propionate on Growth Performance and Carcass Traits in Broilers

Chromium has been considered by many nutritionists as an essential nutrient for animals and humans. Research on the use of Cr from organic sources in poultry is limited. Two experiments were conducted to determine the effects of dietary addition of 0, 200, 400, or 800 ppb Cr as chromium propionate on growth performance and carcass traits in 0- to 42- or 0- to 49-d-old broilers. The results of these experiments indicate that Cr as chromium propionate improved feed efficiency in the later phases of growth and decreased mortality in one experiment but not another. Also, chromium propionate supplementation had no effect on carcass traits.     

达氟沙星(Danofloxacin)在鸡体内的组织残留

建立了坞组织中达氟沙星(Danonoxacin)的高效液相色谱(HPLC)测定方法，并测定了鸡单次内服(每千克体重5mg)给药后组织中的达氟沙星残留特征。组织样品用含0．015mol／L H3PO4和0．015mol／L HClO4的水-甲醇(50:50)提取，50℃水浴酸性水解90min，离心后取上清液作HPLC检测。色谱枉为Hypersil BDSC18柱；荧光检测器检测，激发波长280nm，发射波长440nm；流动相为含0．015mol／L四丁基溴化铵的水-乙腈(905:95，组织检测时为915：85)混合物，85％磷酸调pH为3．0。血浆、肝脏、肾脏、肺脏、肌肉中达氟沙星的检测限为0．02mg／L或0．02Pg／g，血浆样品回收率大于90％，组织样品回收率均大于74％。鸡单次内服甲磺酸达氟沙星后，在60h内各组奴中均可检出药物，但在48h所有组织中药物残留量均低于相应的MRLs(最高残留限量)。结果表明，达氟沙星在鸡组织中消除相对较慢。     

国产碘醚柳胺在绵羊体内的药代动力学及组织残留量的研究

给绵羊单剂量口服碘醚柳胺(7.5mg/kg),用HPLC法测定不同时间的血浆药物浓度。结果,碘醚柳胺在血浆中药物代谢动力学符合开放性二室模型,动力学方程为: C_t=208.586 8e~(-0.4756(t-0.5426)) 18.760 5e~(-0.0439(t-0.5426))-227.445e~(-0.5328(t-0.5426))口服碘醚柳胺后,达峰时间(Tmax)为3.698 9±0.197 4d;峰浓度(Cmax)为18.760 5±1.564 6μg/mL;消除半衰期(T(1/2)β)为15.800 6±0.445 7d;曲线下面积(Auc)为459.000 0±62.531 3μg·d/mL。碘醚柳胺在绵羊的肝、肾、胆汁、肌肉中的残留量:停药后28d分别为0.359 9、0.243 2、0.157 9、0.100 0μg/g;停药后50d,肝脏中的残留量为0.100 0μg/g,其它组织中均检测不到;停药后60d,各组织中均无残留。     

Effect of Testosterone Administration and Spiking on Reproductive Success of Broiler Breeder Flocks

Age negatively affects reproductive success of broiler breeder flocks. One of the main hormones involved in the change of fertility with the age is testosterone (TT). The introduction of young males at later production stages of broiler flocks is known as spiking and is expected to reduce the fertility decline with age. The aim of this study was to determine the effect of injection of different levels of TT and the effect of spiking on reproductive fitness of broiler breeder flocks. Two experiments were conducted on Ross 308 breeder flocks for 10 weeks (41–50 weeks of age). The experiment 1 included a control and three treatments corresponding to three doses of TT (0.1, 0.2 and 0.3 cc), while the experiment 2 included a control and one treatment corresponding to spiking. The lower dose of TT (0.1 cc) and the spiking clearly slowed down the decline in hatchability. Therefore, either the external administration of TT to the males when the natural concentration of TT starts to decline or spiking the breeder flock with young roosters could contribute to improve reproductive success in later stages of the production cycle in broiler breeder flocks.     

Establishment of an Invasive Prostate Cancer Model in Transgenic Rats by Intermittent Testosterone Administration

We have established a transgenic rat for adenocarcinoma of the prostate (TRAP) model that features uniform adenocarcinoma development in prostatic lobes at high incidence within a short experimental period. However, no invasive carcinomas with reactive stroma characteristics similar to those in man were observed. We therefore have focused on a new model for invasive carcinoma of the prostate using TRAP rats. In experiment 1, male TRAP rats in groups 1 and 2 were treated with orchiectomy at day 0 of the experiment. Rats in groups 1–3 underwent testosterone propionate (TP) implantation from weeks 1 to 4 and from weeks 6 to 16. Rats in groups 1 and 3 were given 3,2’-dimethyl-4-aminobiphenyl (DMAB) after TP implantation. The rats of group 4 served as controls. In experiment 2, the rats were divided into three groups, none of which received DMAB or orchiectomy, treated with TP continuously or with the treatment withdrawn once or twice. In experiment 1, invasive adenocarcinomas with abundant collagenous stroma were found in the dorsolateral and anterior prostate, some of which showed perineural space invasion at week 16. The number of invasive carcinoma foci was most frequent in group 3. In experiment 2, invasive adenocarcinoma development in the lateral prostates was correlated with the number of TP administration/withdrawal cycles. In conclusion, our newly established rat model for invasive adenocarcinoma of the prostate could serve as a useful preclinical model for evaluating the in vivo efficacy of preventive and therapeutic agents targeting of the tumor microenvironment.