雏鸡在冷暴露下体内相关激素的动态变化

120只5日龄公雏鸡用以研究不同强度的冷暴露对雏鸡内分泌的影响.相关激素测定的结果表明血清中三碘甲腺原氨酸(T3)、甲状腺素(T4)、胰岛素和糖皮质激素的含量随冷暴露的时间不同而发生变化.在(10±1)℃环境下,T3和T4在血清中的含量波动范围较大,胰岛素和皮质醇波动范围较小;而在(15±1)℃环境下,T3波动范围小,T4仅在冷暴露后8 h下降明显,胰岛素和皮质醇波动范围较大并出现2次峰值.     

副肾皮质刺激激素引起牛卵泡囊肿的试验

作者进行了给牛投与促副肾皮质刺激激素(ACTH)而引起卵泡囊肿的试验。给发情周期正常的4头荷兰种经产牛,从排卵后第14天开始连续两周每日肌肉注射3毫克ACTH,通过直肠触诊及用超声波断层装置检查卵巢。在接近发情预定期6天左右,间隔1～4小时由颈静脉采血,其他期间按1～3天采1次。通过R1A法测定血液中LH、FSH、黄体酮及雌二醇—17β的值。结果,在开始给予ACTH后的第7天的排卵预定日没引起排卵,但在第7～12天全部试验牛都出现了直径约25毫米的囊肿卵泡。血液中LH及FSH的值出现的变化也相类似。在没处置期间的排卵前,可见到两种激素的波动,但     

沼泽型水牛发情周期生殖激素变化的研究

采集9头沼泽型水牛经同期发情处理后的血样,采用放射免疫测定法(RIA)测定其血清生殖激素浓度,并分析了不同年龄水牛的生殖激素变化情况。结果表明:(1)青年水牛FSH、LH峰值分别出现在发情后53.67±15.85h、49.67±15.42h,5h左右出现一个E2峰值(24.12±11.28pg/mL);经产水牛则分别为25.67±12.44h、17.67±6.33h,48h出现E2峰值(21.73±8.72pg/mL)。(2)青年水牛FSH水平在第0、7、15d各出现一个峰值,到下次发情前一天又出现一个高峰值(11.69±0mIU/mL);LH水平第0、8、20d各出现一个峰值,第3～8d维持相对较高的水平(7.99±1.83～11.90±3.63mIU/mL);第14d后E2水平呈上升趋势,第22d达到最高峰(65.23±44.60pg/mL);P4水平在第1～4d呈上升趋势,第14、17、19d最高,此后下降。(3)经产水牛FSH水平除在第0、7、13、18、22d各出现一个峰值外,其他时间以较大的幅度(1.37±0.88～2.67±0.61mIU/mL)波动;LH水平除在第2、6、14、17、20d有峰值出现外,其他时间波动(3.92±2.92～7.85±1.21mIU/mL)也很大;P4水平在发情前4d处于较低水平,第5～11d维持相对较高的水平(0.087±0.0167～0.296±0.282ng/mL),第13～18d呈明显的上升趋势,之后迅速下降;E2水平除在发情第2、10、23d各出现一个峰值,第20～23d迅速升高外,其他时间基本恒定。     

发情旺季母水牛生殖激素水平变化的研究

为了研究发情旺季母水牛生殖激素水平的变化规律,试验采用酶联免疫分析方法(ELISA)测定了发情周期血样中的促卵泡素(FSH)、促黄体素(LH)、雌二醇(E2)和孕酮(P4)4种激素,并分析了这些生殖激素在发情周期中的变化规律。结果表明:血清中FSH和LH的含量均由排卵前的第4天开始缓慢上升,排卵前达到峰值,在排卵后又明显下降;E2的含量在排卵前1天出现峰值,在排卵后第9天又出现1个小波峰;P4的含量在排卵后的第5天明显上升,第13天时达峰值,在排卵前3天出现最低水平。     

实验性脂肪肝鸡血液素和脂肪类含量变化的研究

本实验研究产蛋鸡在脂肪肝形成过程中激素的变化规律与脂类代谢的关系。结果表明：血脂和胆固醇含量各周之间差异显著，呈明显上升趋势，第４２天实验结束达到峰值，分别为２１８４．２６毫克／１００毫升和１１４．６９毫克／１００毫升。血清雌二醇含量明显上升，睾酮含量在各周之间没有显著差异。血清三碘原氨酸（Ｔ３）在各周之间也有显著差异，由于喂饲大量ＫＩ，有一个较大上升波动，第２８天后急剧下降，与血脂含量呈极显著的负相关。血清甲状腺素（Ｔ４）含量在第２８天前各周波动不显著，第３５天达到峰值，第４２天时下降为１．７６毫克／毫升。在个体测定中，Ｔ４含量有一个明显上升趋势，这也与喂饲ＫＩ有关。     

不同断奶日龄与精料补饲量对舍饲母羊产后雌二醇与孕酮的影响

采用不同精料补饲量(0.25 kg/d、0.50 kg/d、1.00 kg/d)饲喂不同断奶日龄(42 d和63 d)的36只产后舍饲母羊,利用化学发光法和放射性免疫法分别对其0~91 d外周血液中雌二醇(17β-E2)和孕酮(P4)的变化规律进行研究。结果表明:母羊在产羔后当天17β-E2的浓度为175.22 pg/m L±22.64 pg/m L,然后呈现下降趋势,断奶后呈现上升趋势,之后出现不规则的波动;在产羔后当天P4的浓度为0.13 ng/m L±0.02 ng/m L,之后维持较低的水平,在断奶前基本处于较低水平,之后出现波动,在断奶后出现小范围的升高之后降低。在断奶日龄上,舍饲母羊17β-E2和P442 d断奶出现峰值要早于63 d断奶。在精料补饲水平上,0.50 kg/d的精料补饲情况下,17β-E2波动出现较早;对17β-E2与P4变化趋势对比得出,在42 d断奶与0.50 kg/d的精料补饲下有利于频繁产羔技术体系,实现一年两产或两年三产模式。以上结果对产后母羊内分泌恢复和发情机理探讨提供了理论基础。     

确定母犬最佳配种时间的常用方法

正母犬的最佳配种时间很可能是在可受精期或可受精期即将开始时。自然交配时,生育力的峰值出现在促黄体素(LH)峰值出现前的1 d至之后的5~6 d。因此,可以根据监测LH峰值出现时间的方法确定配种时间。1激素测定血浆LH浓度测定是一种准确可靠的判定最佳配种时间的方法,但目前还没有简单易行的商用方     

湖羊、三北羊发情期外周血液中促黄体素、雌二醇和孕酮含量的变化

用放射免疫法测定了湖羊和三北羊发情周期外周血液的LH、17β-雌二醇和孕酮的含量。发情的LH峰值:湖羊为126.54±7.71ng/ml,三北羊为123.38±9.6ng/ml(1)>0.05)。发情开始时间距LH峰值在两种羊之间有显著差异(P<0.01)。整个情期湖羊雌二醇含量高于三北羊(P<0.05),湖羊为36.18±1.52pg/ml,三北羊为28.72±1.92pg/ml,两种品种羊在周期1—3天孕酮含量维持低水平,周期的5—13天有一峰值,湖羊为7.92±0.18ng/ml,三北羊为6.10±0.1ng/ml,有极显著性差异(P<0.01)。在第13天孕酮含量开始下降,第16天下降到最低值。     

狸獭发情周期中17β-E_2和P_4分泌规律的研究

应用放射免疫分析法(RIA)首次测定了5只雌性成年狸獭发情周期中外周血浆17β-雌二醇(E_2)和孕酮(P_4)的含量。结果表明,在母狸发情盛期17β-E_2达峰值62.19pg/ml,以后开始下降,并在一定范围内上下波动,到下一个发情周期的发情期就又开始上升。而P_4含量在发悄盛期最低2.48ng/ml,到18天左右峰值达6.26ng/ml,到第二个发情周期前,又迅速下降。二者的这种变化规律与该动物发情周期的表现规律相吻合。     

补饲硒 维生素E对奶牛激素水平的影响

为进一步研究硒、维生素E对奶牛繁殖性能的影响,在某奶牛场选择临床健康、年龄、体重相近的荷斯坦奶牛50头。随机分为对照组、试验A组和试验B组,对试验A组补饲维生素E,试验B组补饲亚硒酸钠维生素E,每5 d采血1次,用高效液相色谱法测定血清中的雌三醇、4-壬基酚、17α-乙烃基雌二醇、17α-雌二醇、17β-雌二醇、双酚A的含量。结果显示,补饲维生素E、亚硒酸钠维生素E后血液中雌三醇、4-壬基酚、17α-雌二醇、17β-雌二醇、双酚A的含量均有所增加,补亚硒酸钠维生素E后各激素含量的变化明显优于补饲维生素E的变化。     

激素调控促进动物生长发育的研究

激素对机体的代谢、生长、发育、繁殖、性别、性欲和性活动等起重要的调节作用。动物机体通过各种内分泌腺分泌的激素,间接调节动物机体的活动。内分泌腺分泌的激素直接进入血液、随着血液循环到达身体各个部分,在一定的器官或组织中发生作用,从而协调动物机体新陈代谢、生长、发育、生殖及其它生理机能,使这些机能得到兴奋或抑制,使它们的活动加快或减慢。生长激素可以促进蛋白质的合成与骨的生长,甲状腺激素促进新陈代谢和生长发育,可以提高神经系统的兴奋。胰岛分泌的激素可以控制糖类代谢,调节血糖含量。性激素促进生殖器官的生长发育,维持第二性征。     

不同月份产羔母羊泌乳期生殖激素与生长激素监测

为了解不同月份生产的奶山羊泌乳期生殖激素与生长激素(GH)变化规律,随机抽取1、3、5和8月份分娩的奶山羊各10只,于分娩后0 d、7 d、1~8个月(每月的第15天)时采集母羊静脉血,分离血清,采用ELISA试剂盒检测母羊外周血中催乳素(PRL)、卵泡刺激素(FSH)、促黄体生成素(LH)、雌激素(E₂)、孕酮(P₄)和GH水平变化。结果显示:不同月份产羔母羊泌乳期间外周血中同一激素的动态变化趋势一致;在整个泌乳期间,1、3、5、8月份产羔母羊PRL、FSH、LH、P₄、E₂、GH含量的动态变化范围分别为446.17~221.72 ng·L^-1、9.49~3.82 U·L^-1、351.17~218.16 pg·mL^-1、4086.83~3568.15 pmol·L^-1,33.74~22.30 ng·L^-1、30.36~11.57μg·L^-1;不同月份产羔母羊外周血中GH水平在相同泌乳期均无显著差异(P>0.05),FSH水平在0 d有显著差异(P<0.05),P₄水平在8个月时有显著差异(P<0.05),PRL水平在泌乳的0 d和2、3、8个月时有显著差异(P<0.05),LH水平在泌乳的0 d、2个月时有显著差异(P<0.05),E₂水平在泌乳0 d、3个月和8个月时有显著差异(P<0.05)。结果表明:奶山羊产羔月份的不同对泌乳期间的激素水平有一定的影响,但动态变化趋势一致。     

日粮中添加半胱胺对雄性水貂的生产性能、血液激素水平的影响

选用64只初始体重和日龄均匀的雄性美洲标准水貂,随机分成4组,每组16只。采用单因子随机试验设计,研究水貂日粮中添加半胱胺对育成期雄性水貂的生产性能、血液激素水平和冬毛生长期毛皮质量的影响。结果表明,在日粮中添加半胱胺100 mg/kg体重和200 mg/kg体重,可显著提高雄性美洲标准水貂120日龄时的体重(P<0.05),并极显著提高80~120日龄的日增重(P<0.01)。日粮中添加100 mg/kg体重和200 mg/kg体重半胱胺能提高育成期水貂血液中甲状腺素T3和T4的水平;添加200 mg/kg体重半胱胺也能提高育成期水貂血液中的生长激素水平。冬毛生长期日粮中添加200 mg/kg体重的半胱胺能明显提高冬皮的皮重/皮长指数。     

The expressions of some metabolic hormones (leptin,ghrelin and obestatin) in the tissues of sheep tongue

In this study, we aimed to observe the localization and expression of peptide hormones—leptin, ghrelin and obestatin—in the sheep tongue by immunohistochemistry. For that purpose, tongues of ten adult sheep were used. Leptin expression of moderate intensity was observed in the basal and parabasal epithelial cells of the luminal epithelium, and leptin was strongly expressed in the taste buds of the circumvallate and fungiform papillae and in von Ebner's glands. Ghrelin was primarily expressed in some of the skeletal muscle cells and the smooth muscle cells of the middle layer of blood vessels. A strong expression was observed in the epithelial cells lining the base of the groove surrounding the circumvallate papillae. Obestatin expression was particularly strong in the epithelial cells of the salivary ducts. It was also stronger in the von Ebner's glands than in the seromucous glands. Leptin, ghrelin and obestatin were shown to be produced at varying levels in different cell types, including epithelial, stromal and skeletal muscle cells, as well as in ganglion neurons, neural plexuses and blood vessels in the sheep tongue. Cellular localization and expression of these peptide hormones have not been investigated in many species including sheep.     

Effect of ovarian hormones on maturation of dendritic cells from peripheral blood monocytes in dogs

Previously, we reported that ovarian hormones affect the immune response against E. coli isolated from the dogs affected with pyometra. In order to investigate mechanisms underlying the immune modulation, we examined the effects of ovarian hormones on the generation of dendritic cells (DCs), the most potent antigen presenting cell. DCs were differentiated from peripheral blood monocytes (PBMOs) using a cytokine cocktail. Both estrogen receptor and progesterone receptors were expressed by the PBMOs and immature DCs. When various ovarian hormones were added to the culture for the DC differentiation, progesterone significantly decreased the expression of DC maturation markers, such as CD1a, CD80 and CD86, on mature DCs. Conversely, the addition of estrogen to the cultures increased the expression of CD86, but not other maturation makers. Furthermore, DCs differentiated in the presence of progesterone did not stimulate allogeneic mononuclear cells in PB. Taken together, these results indicate that progesterone diminishes the maturation of DCs, leading to decreased immune responses against invading pathogens.     

日粮中长期添加大豆黄酮对产蛋鸡产蛋性能及有关内分泌的影响

试验旨在探讨日粮中长期添加大豆黄酮对产蛋高峰期蛋鸡采食和生产性能的影响及有关内分泌机制。40羽180日龄产蛋鸡,均分为2组,对照组饲喂基础日粮,试验组饲喂基础日粮+大豆黄酮(6mg/kg),试验期为150d。结果显示:试验组蛋鸡采食量、产蛋率、只日蛋重、每枚蛋重均显著提高,料蛋比显著下降;血清17β-雌二醇、T3、T4水平均显著提高,而血清瘦素(leptin)水平有下降的趋势。试验结果表明,大豆黄酮可调控血液激素水平而提高产蛋鸡生产性能,并使产蛋高峰期得到延长。     

Endocrine Changes and Their Relationships with Body weight of Growing Yak

Concentrations of growth hormone (GH), insulin, thyroxin(T4 ) and 3,3 ' 5 '-tri-iodothyronine (T3)in blood samples of growing yak during different seasons were determined by radio-immunoassay.Changes in bodyweight of the growing yak and compositions of grass were also measured. The seasonal changes in hormones were significant (at least P＜0.05). In the same season, variation in hormonal concentration was affected by the growth stage of the animal. The bodyweight gains varied in different seasons, with significant increase from May to September and decrease from January to May. Correlation analysis indicated that T4 had a significant positive correlation with bodyweight of the growing yak(r= 0.323,P＜0.05) ,but other hormones did not have significant correlations with bodyweight. The results show that annual cycle of weight loss and gain is attributable to the seasonal changes in feed supply and that the seasonal changes in the concentrations of the assayed hormones were indirectly dependent on grass growth.     

不同断奶日龄仔猪血液中生长相关激素的检测

为探讨断奶日龄对仔猪血液生长相关激素指标的影响,试验从8窝"杜×长×大"仔猪中选取出生日龄相近、初生体重一致的健康仔猪24头,随机分为4个试验组,每个试验组设6个重复,每个重复1头仔猪,4组仔猪分别于14、21、28、35日龄断奶。至42日龄时,所有仔猪宰杀采血,利用放射免疫分析法进行血浆生长激素(GH)、胰岛素(INS)、三碘甲状腺原氨酸(T3)和四碘甲状腺原氨酸(T4)含量检测。结果表明,不同日龄组断奶仔猪血浆GH、T3和T4水平无显著性差异(P0.05);35日龄组断奶仔猪血浆INS含量显著高于14日龄断奶组(P0.05)。结果提示,不同断奶日龄对仔猪生长相关激素无显著影响。     

Optimal Testing for Thyroid Hormone Concentration after Treatment with Methimazole in Healthy and Hyperthyroid Cats

Background: Methimazole suppresses thyroid hormone synthesis and is commonly used to treat feline hyperthyroidism. The degree of variation in thyroid hormone concentrations 24 hours after administration of methimazole and optimal time for blood sampling to monitor therapeutic efficacy have not been determined.
Objective: To assess thyroid hormone concentration variation in serum of normal and hyperthyroid cats after administration of methimazole.
Animals: Four healthy cats and 889 retrospectively acquired feline thyroid hormone profiles.
Methods: Crossover and retrospective studies . In the crossover study, healthy cats were treated with increasing doses of oral methimazole until steady state of thyroid suppression was achieved. Thyroid hormones and thyroid stimulating hormone (TSH) were serially and randomly monitored after methimazole. Paired t -tests and a 3-factor analysis of variance were used to determine differences between thyroid hormone concentrations in treated and untreated cats in the crossover study. Thyroid profiles from methimazole-treated hyperthyroid cats were retrieved from the Diagnostic Center for Population and Animal Health database and reviewed. Linear regression analysis evaluated relationships of dosage (mg/kg), dosing interval (q24h versus q12h), and time after methimazole to all thyroid hormone concentrations.
Results: All serum concentrations of thyroid hormones were significantly suppressed and TSH was significantly increased for 24 hours after administration of oral methimazole in healthy cats ( P < .005). In hyperthyroid cats, there were no significant relationships between thyroid hormone concentrations and time postpill or dosing interval.
Conclusions: Timing of blood sampling after oral methimazole administration does not appear to be a significant factor when assessing response to methimazole treatment.     

Dynamics of Follicular Blood Flow,Antrum Growth,and Angiogenic Mediators in Mares From Deviation to Ovulation

This study aimed to investigate dynamics of dominant and subordinate follicles' change of dimensions, vascularity, and angiogenic hormones from deviation to ovulation. Ten cyclic mares were subjected to daily blood sampling and Doppler examination along two estrous cycles. Three diameters were recorded for each follicle to estimate its area and volume. Leptin, insulin-like growth factor-I (IGF-1), nitric oxide (NO) and estradiol were measured. Area of color and power Doppler modes with antral area and circumference of all follicles was measured in pixels. Follicles were classified into first large preovulatory follicle (1st F-ov), second large (2nd F-ov), and third large (3rd F-ov) on the ovulating ovary and on the contralateral nonovulating ovary into first (1st F-contra) and second large (2nd F-contra). Days before ovulation significantly (P < .0001) affected all dimensions of preovulatory follicle. With the increase of diameter, area, volume, area in pixel, antrum area, and circumference of 1st F-ov, those of all subordinates were decreasing. The blue flow area, power, and power minus red blood flow area of 1st F-ov increased from day −6 till day of ovulation (day 0), but red blood flow area significantly decreased. First large follicle had the lowest percent of colored pixels and percent of the colored pixels without antrum. Estradiol and leptin increased from day −6 till day 0, but IGF-1 decreased till day −1 and NO achieved a peak on day −3 then decreased till day 0. In conclusion, antrum growth, blood flow, and angiogenic hormones play a role in maturation and ovulation of the dominant follicle in mares.