梅花鹿鹿茸异位生长研究

为了揭示鹿茸发生机理,阐明生茸区骨膜在鹿茸发生中的作用,选择4只1周岁雄性梅花鹿,在鹿茸发生前,通过外科手术将一侧完整的生茸区骨膜摘除并移植到额骨上。结果,摘除骨膜的生茸区没有发生鹿茸,而在被移植的额骨部位上发生了鹿茸且生长发育正常。证明了生茸区骨膜是鹿茸发生的组织基础,同时为通过异位生茸提高鹿茸产量开辟了新的途径。     

梅花鹿鹿茸异位生长的试验

为了揭示鹿茸发生机理,阐明生茸区骨膜在鹿茸发生中的作用,选择4只1周岁雄性梅花鹿,在鹿茸发生前,通过外科手术将一侧完整的生茸区骨膜摘除并移植到额骨上。结果,摘除骨膜的生茸区没有发生鹿茸,而在被移植的额骨部位上发生了鹿茸且生长发育正常。证明了生茸区骨膜是鹿茸发生的组织基础,同时为通过异位生茸提高鹿茸产量开辟了新的途径。     

日粮添喂伊普异黄酮影响去势仔猪生长及有关内分泌水平

断奶仔猪(雌雄均去势)60头随机分为对照组和试验组,分别饲喂基础日粮和基础日粮添加5mg/kg日粮的伊普异黄酮,试验期持续1个月。与对照组相比,试验组增重提高26.3%(P<0.01),饲料利用率提高33.95%,其中雄性去势仔猪增重比雌性提高显著。血液胰岛素样生长因子(IGF-I)含量雌、雄分别提高24.72%和44.76%,平均提高33.93%;睾酮含量雌、雄分别提高40.38%和40.98%,平均提高40.68%。血钙含量试验组比对照组高14.60%,其中雌、雄分别高9.76%和19.44%。上述试验结果表明,伊普异黄酮影响神经内分泌系统,提高睾酮、IGF-I和血钙水平,从而促进去势仔猪增重,而对雄性的作用比雌性显著。     

用GFP基因标记梅花鹿生茸骨膜细胞

为了用绿色荧光蛋白(green fluorescent protein,GFP)标记梅花鹿生茸区骨膜(antlerogenic periosteum,AP)细胞,试验首先构建了含GFP基因的重组质粒pLNHX-GFP,将重组质粒与包装质粒VSV共转染包装细胞GP 2-293,获得复制缺陷型逆转录病毒上清液,感染培养的梅花鹿生茸区骨膜细胞,检测GFP在骨膜细胞中的表达情况,用G418对感染后的细胞进行筛选。结果表明:试验获得了能稳定地表达GFP的生茸骨膜细胞。     

圈养雌虎对不同配偶存在明显选择心理

为了研究圈养雌虎对不同配偶是否具有选择性及可能的影响因素,试验采用行为取样法对泰山东北虎园5只(2雌、3雄)东北虎的交配行为进行观察,并利用放射免疫分析法(RIA)对雄虎粪便中的睾酮浓度进行测定。结果表明:在交配过程中,雌虎对不同配偶表现其选择心理的日均邀配次数存在极显著差异(P0.01),并且日均邀配次数与雄虎睾酮浓度呈一致性,但不同雄虎的睾酮浓度差异不显著(P0.05)。说明圈养雌虎对不同配偶存在明显的选择心理,并且这种心理受雄虎睾酮浓度的影响。     

日粮添加大豆黄酮对去势仔猪生长性能及有关内分泌的影响

断奶仔猪 (公母均去势 )随机分为对照组和实验组 ,分别饲喂基础日粮和基础日粮添加 5mg/kg日粮的大豆黄酮 ,试验期持续一个月。与对照组相比 ,实验组的增重和饲料利用率均有所改善 ,但存在明显的性别差异 :雄性去势仔猪增重提高 5 9.15 % (P <0 .0 1) ,但雌性去势仔猪低 2 6 .39% (P <0 .0 5 ) ;血液胰岛素样生长因子 (IGF I)含量平均提高 2 6 .6 0 % (P <0 .0 5 ) ,公、母分别为提高 5 0 .91%和降低 9.6 6 % ;睾酮含量提高 17.4 6 % (P <0 .0 5 ) ,其中雄性提高 18.4 1% ,而雌性降低 6 .86 % ;血钙含量提高 11.78% (P <0 .0 5 ) ,其中雄、雌分别提高 17.92 % (P <0 .0 5 )和 6 .4 7%。上述实验结果表明 ,大豆黄酮对去势仔猪生长和有关激素状态表现明显的性别差异性。能够显著促进去势仔公猪生长和睾酮、IGF I分泌 ,而对雌性去势仔猪则起抑制性影响     

水牛瘤胃细菌存在雌二醇受体的初步研究

本试验应用DCC法对水牛瘤胃细菌进行测定。结果表明:瘤胃细菌可专一性地结合17β-雌二醇,并出现饱和现象,饱和曲线呈S形。用单点法计算得最大结合容量为50～65fmol/mg蛋白。Scatchard图为倒“U”形曲线。配体特异性竞争试验表明:瘤胃细菌雌二醇受体和皮质醇及睾酮有轻微交叉反应,交叉率分别为5.6％和14.4％;对孕酮和醛固酮则没有交叉反应。提示瘤胃细菌存在雌二醇受体,但和典型靶细胞上的雌二醇受体可能有一定的区别。     

一例蛮羊截肢手术的报告

蛮羊属哺乳纲,偶蹄目,牛科,蛮羊属,是非洲仅有的一种野羊,分布在北非摩洛哥至埃及、大西洋海岸到红海。蛮羊栖息在荒凉的岩石和沙土地带,他们一般结戚家族生活在一起,其中一雄羊统领整个家族,其他成员为雌性和未成年幼仔。我园蛮羊现有共13只,8雄5雌,一群在散放区饲养共6雄,还有一群2雄5雌共7只混养,进行繁殖。     

应用cDNA微阵列芯片技术筛选猪蛔虫性别差异表达基因的研究

采用cDNA微阵列芯片技术，从所构建的猪蛔虫雌、雄成虫cDNA消减文库分别挑取1044和1119个克隆，PCR扩增其插入片段，经纯化后点样于预先处理好的基片上（双点杂交），制备成cDNA微阵列芯片。将分别标记荧光素Cy3-dUTP和Cy5-dUTP的雌虫和雄虫cDNA探针，与制备好的cDNA芯片杂交（平行进行反标杂交试验）。根据每个点杂交后的Ratio值，筛选出双点杂交和正反标中都同时具有表达差异的基因克隆共1559个。将表达差异最明显的前831个克隆进行测序，获得720个有效序列，经生物信息学分析发现，雄虫特异表达的主要精于蛋白和雌虫特异表达的卵巢信息蛋白的基因序列多数与新杆属线虫存在同源性，有31个可能是新的ESTs。性别差异表达基因及其相关生物信息的获得为下一步研究基因功能奠定了基础。     

畜牧兽医学报第21卷总目录

第1期(‘1990年2月)影响蛋鸡血浆极低密度脂蛋白(VLDL)含量的环境因素………吴庆鹉林海 杨全明 尹逊河 余振华( 1)注射猎生长激素对北京黑猪血液葡萄糖、非蛋白氮和游离脂肪酸含量的影响 ……………………………………………………………………………张少英牛文彪常档霞齐顺章(7)梅花鹿生茸区骨膜皋酮特异结合的测定………………李春义邴国良张学文 赵世臻 邹继超 范植明(11)屡配不孕母牛发情开始后八天内血清促黄体索(LH)含量的变化……龚振明 耿1什祥 安 民 童开银(1 s)枫泾公绪初情期前后外周血清巾皋酮、促黄体素及皮质醇的含量变化 …     

Experimental persistent infection with bovine viral diarrhea virus in white-tailed deer

Bovine viral diarrhea virus (BVDV) infections cause substantial economic losses to the cattle industries. Persistently infected (PI) cattle are the most important reservoir for BVDV. White-tailed deer (Odocoileus virginianus) are the most abundant species of wild ruminants in the United States and contact between cattle and deer is common. If the outcome of fetal infection of white-tailed deer is similar to cattle, PI white-tailed deer may pose a threat to BVDV control programs. The objective of this study was to determine if experimental infection of pregnant white-tailed deer with BVDV would result in the birth of PI offspring. Nine female and one male white-tailed deer were captured and housed at a captive deer isolation facility. After natural mating had occurred, all does were inoculated intranasally at approximately 50 days of pregnancy with 10(6) CCID(50) each of a BVDV 1 (BJ) and BVDV 2 (PA131) strain. Although no clinical signs of BVDV infection were observed or abortions detected, only one pregnancy advanced to term. On day 167 post-inoculation, one doe delivered a live fawn and a mummified fetus. The fawn was translocated to an isolation facility to be hand-raised. The fawn was determined to be PI with BVDV 2 by serial virus isolation from serum and white blood cells, immunohistochemistry on skin biopsy, and RT-PCR. This is the first report of persistent infection of white-tailed deer with BVDV. Further research is needed to assess the impact of PI white-tailed deer on BVDV control programs in cattle.     

Testosterone increases urinary free felinine, N-acetylfelinine and methylbutanolglutathione excretion in cats (Felis catus)

Two days after castration, urinary free felinine plus N-acetylfelinine decreased 24% in male cats, but, by day 5, the concentration had not decreased to that routinely found in males that have been castrated for several months. In a second experiment, three groups of castrated adult male cats received different subcutaneous injections: control (carrier), testosterone, testosterone plus estradiol. A fourth group of intact adult female cats received a testosterone injection. Urine was collected and analysed for free felinine, N-acetylfelinine and 3-methylbutanolglutathione. Baseline blood testosterone and estradiol concentrations were low during the pre-period, but increased sharply after hormone injections. The concentration of all three urinary metabolites increased as a result of testosterone injections with estradiol not modulating the effect. The effect of testosterone was not gender dependent. The concentration of free felinine, N-acetylfelinine and 3-methylbutanolglutathione in the urine remained low in the placebo control group throughout the study. The relative molar contribution of free felinine to the total amount of felinine containing compounds increased due to testosterone treatment, while the contribution of 3-methylbutanolglutathione and N-acetylfelinine decreased. Testosterone increases free felinine, N-acetylfelinine and 3-methylbutanolglutathione excretion in castrated adult male and intact female cats, whereas estradiol does not modulate this effect.     

Steroid hormone concentration profiles in healthy intact and neutered dogs before and after cosyntropin administration

The purpose of this study was to determine steroid hormone concentration profiles in healthy intact and neutered male and female dogs. Seventeen intact female dogs, 20 intact male dogs, 30 spayed female dogs, and 30 castrated male dogs were used in this study. Serum samples were collected before and 1h after cosyntropin administration, and serum concentrations were determined for cortisol, progesterone, 17-OH progesterone (17-OHP), dehydroepiandrosterone sulfate (DHEAS), androstenedione, testosterone, and estradiol. Intact male dogs had greater concentrations of DHEAS, androstenedione, and testosterone. Intact female dogs had greater concentrations of progesterone. There was no significant difference in estradiol concentration among the four groups. Intact male dogs had lower concentrations of cortisol post-stimulation. DHEAS and testosterone did not increase in response to ACTH in intact males, and estradiol concentrations did not increase in response to ACTH in any group. Results from this study will enhance interpretation of suspected adrenal and/or gonadal disorders of dogs. Because estradiol concentrations were similar in all groups of dogs, measuring estradiol may not be a useful diagnostic test. Cortisol concentrations for intact male dogs with hyperadrenocorticism may be lower than those of female or neutered dogs.     

Androgen and estrogen receptors in bovine skeletal muscle: relation to steroid-induced allometric muscle growth

The presence of free androgen (AR) and estrogen receptors (ER) was demonstrated in bovine skeletal muscle. Androgen receptor concentrations in neck muscle from cattle of different sexes and stages of development were related to hormonal status. In mature bulls (mean weight 600 kg), no free AR was detectable. Highest AR concentrations were measured in mature bulls (517 kg) castrated 24 h prior to slaughter (.85 +/- .21 fmol/mg protein). In female calves (155 kg), AR concentrations (.56 +/- .14 fmol/mg) were greater (P less than .01) than in male calves (.20 +/- .08 fmol/mg) of the same weight. Androgen receptors and ER in skeletal muscle of neck, shoulder, abdomen and hind leg of female and male calves were compared. There was no significant difference between AR concentrations in the neck, shoulder and hind leg, but concentrations were lower (P less than .05) in abdominal muscle. Estrogen receptor concentrations in neck, shoulder, abdomen and hind leg were not different between sexes (P less than .05). In male calves, ER content was lower (P less than .05) in abdominal than in other muscles. Estrogen receptor concentrations in muscles of female calves did not differ (P less than .05). The pronounced sensitivity to estrogens and androgens in the neck, shoulder, and hind leg of calves, being free of the respective hormone, may partly explain the characteristic conformation in calves treated with estrogenic and androgenic steroids and the sexual dimorphism of muscle growth.     

Serum testosterone and estradiol 17-beta concentrations in 15 dogs with perineal hernia

Serum testosterone and estradiol 17-beta concentrations, and serum testosterone-to-estradiol ratio were evaluated in 15 dogs (greater than or equal to 5 years old) with perineal hernia (9 sexually intact males and 6 castrated males) and in 9 clinically normal sexually intact male dogs greater than or equal to 5 years old. There was no significant difference in serum testosterone-to-estradiol ratio between sexually intact male dogs with perineal hernia and clinically normal sexually intact male dogs. In castrated dogs with perineal hernia, serum testosterone concentration and testosterone-to-estradiol ratio were significantly (P less than 0.05) lower, compared with those values in sexually intact dogs with perineal hernia and in clinically normal sexually intact male dogs. There was no significant difference in serum estradiol 17-beta concentration among sexually intact male dogs with perineal hernia, castrated dogs with perineal hernia, and clinically normal sexually intact male dogs. Serum testosterone and estradiol 17-beta concentrations in dogs with perineal hernia did not differ from those values in clinically normal male dogs of the same age. Castration cannot be recommended for the treatment of perineal hernia unless a castration-responsive contributing factor such as prostatomegaly is identified, unless the pelvic diaphragm of dogs with perineal hernia has high sensitivity to normal or low serum testosterone and estradiol 17-beta concentrations, or unless there is documentation that other androgens and/or estrogens are involved.     

Effects of testosterone on the prevention of T-2 toxin-induced adrenocortical necrosis in mice

To evaluate the effect of exogenous testosterone on the development of T-2 toxin-induced necrosis of adrenal glands, mice were allotted to 3 treatment groups. Each treatment group contained castrated male, and castrated and sexually intact female mice. Each mouse in group 1 was given 0.16 mg testosterone propionate at 48-hour intervals for a total of 12 injections, group-2 mice were given similar injections of only the vehicle, and group-3 mice were given no treatment. Twenty-four hours after the last injection, the mice in all 3 groups were exposed for 10 minutes to an aerosol of T-2 toxin. All mice alive at 24 hours after exposure were euthanatized and the adrenal glands and thymuses were examined histologically. Necrosis of the adrenal cortex was not found in any of the mice given preexposure treatment with exogenous testosterone, whereas all mice given vehicle only or no treatment had T-2 toxin-induced necrosis of the inner portion of the adrenal cortex. Lymphocytolysis in the cortex of the thymus confirmed that each mouse of all 3 treatment groups had experienced systemic mycotoxicosis. The uniform severity of the lesion in all mice suggests that the thymus was not protected by exogenous testosterone administration or by the castration status of the mice. We propose that T-2 toxin-induced adrenal necrosis in mice is prevented by the presence of testosterone.