半胱胺盐酸盐对泌乳中期热应激奶牛生产性能的影响

本试验旨在研究散栏式饲养方式下,饲喂半胱胺盐酸盐对泌乳中期热应激奶牛生产性能的影响。选择48头健康荷斯坦奶牛[体重(562.25±37.85)kg,泌乳天数(123.64±10.67)d,胎次(1.23±0.42)胎,日产奶量(26.58±1.58)kg],根据体重、泌乳天数、产奶量相同或相近的原则,随机分成4组(每组12头),对照组饲喂基础饲粮,试验组分别在基础饲粮中添加半胱胺盐酸盐3、15、30 g/kg。预试期12 d,正试期30 d。结果显示:随半胱胺盐酸盐添加剂量的增加,奶牛呼吸频率和直肠温度呈显著的线性降低(P0.05);干物质采食量、乳脂较正乳产量、能量校正乳产量、乳脂率、乳蛋白率均呈先升高后降低的显著的二次曲线变化(P0.05),并且以添加3 g/kg组的效果较好;正试期末,3、15 g/kg组血清甲状腺素浓度显著低于对照组(P0.05),15 g/kg组血清皮质醇浓度显著高于对照组(P0.05)。结果提示,半胱胺盐酸盐能有效缓解散栏饲养的泌乳中期奶牛热应激,提高产奶量和乳品质,本试验条件下,饲粮中添加3 g/kg半胱胺盐酸盐较为适宜。     

奶牛乳中孕酮水平和超排效果的研究

对12例超排供体母牛固体干奶样孕酮含量进行了放射免疫分析,研究了其与超排效果间的关系。结果指出:(1) 孕酮水平变化规律正常者,超排有效率达100%。即超排前孕酮值>12、超排期发情<10、采卵期>40ng/ml者,其黄体数均>4并获可用胚胎。(2) 超排采卵后注射PGF2α,虽孕酮有下降趋势,但未降低至发情的水平,在有效期内均未出现发情。关于缩短超排后供体的发情期问题,尚需进一步研究。     

轻音乐对奶牛产奶量及血液激素水平的影响

本试验旨在探讨轻音乐对奶牛产奶量及血液激素水平的影响。选取产奶量、年龄、胎次、泌乳期相近的荷斯坦泌乳牛32头,随机分成2组,每组16头。试验组于早、中、晚3次给料时间各播放轻音乐2 h,轻音乐选用理查德·克莱德曼的经典钢琴曲20首,对照组常规饲喂。预试期7 d,正试期60 d。正试期当天起(0 d),每隔10 d测定单产1次并采集血样1次。结果表明,试验组产奶量在第10、40天时显著高于对照组(P<0.05);试验组产奶量在第20、30、50、60天时高于对照组,差异均不显著(P>0.05);整个试验期,试验组平均产奶量较对照组高1.72 kg,差异极显著(P<0.01)。整个试验期,轻音乐能提高奶牛血液中γ-氨基丁酸(GABA)、生长激素(GH)含量,降低血液中皮质醇(COR)、五羟色胺(5-HT)含量,差异均不显著(P>0.05)。综上所述,轻音乐可通过提高奶牛血液中γ-氨基丁酸含量,促进生长激素的分泌,降低皮质醇、五羟色胺的含量,稳定奶牛情绪,从而降低奶牛应激反应,提高产奶量。     

绵羊实验性硒过多症的研究——Ⅴ.血液T、B淋巴细胞及血清蛋白的测定

测定了7只给硒羊血液T淋巴细胞、B淋巴细胞、血清总蛋白、白蛋白、球蛋白(α_1、α_2、β、γ)的动态变化。结果:给硒后T淋巴细胞增多,B淋巴细胞减少,直至试验结束(90d);血清总蛋白和γ球蛋白在给硒后70d以内,血硒水平为0.5749μg/ml以下时,基本无变化,给硒70d后,血硒水平超过0.5749μg/ml时,总蛋白量和γ球蛋白均减少;其他指标未见规律变化。     

果洛藏獒血清蛋白质指标的研究

对果洛州玛沁县３９ 只藏獒的血清蛋白质指标进行研究。结果表明： 果洛藏獒的血清总蛋白、白蛋白含量（ 分别为７７－６４ ｇ／Ｌ 和５１－４９ ｇ／Ｌ）以及血清白蛋白比例较高（６６－３０） , 白球比值（Ａ／Ｇ） 为１－９７ ; 公藏獒血清总蛋白含量显著高于母藏獒（ Ｐ ＜０－０５） ; 成年藏獒的血清总蛋白和白蛋白含量以及白蛋白比例均显著高于幼年藏獒（ Ｐ ＜ ０－０５ 或０－０１） 。     

Einfluß der Milchleistung auf Fruchtbarkeitskriterien der Milchkuh post partum: Auswertung von Progesteronprofilen

Inhalt Der Einfluß der Milchleistung auf Fruchtbarkeitskriterien von Milchkühen (n = 80) post partum (p.p.) wurde unter den standardisierten Bedingungen einer Versuchsherde anhand von Progesteronprofilen analysiert. Progesteron wurde dabei im Milchfett gemessen. Wie in früheren Studien war das herausragende Fruchtbarkeitsproblem die reduzierte Ausprägung von Brunstsymptomen und daraus resultierend Probleme bei der Brunsterkennung und bei der Wahl des optimalen Besamungstermins. Insgesamt verliefen 41,2% aller durch Progesteronmessung ermittelten Ovulationen ohne erkennbare Symptome. 94,8% aller Kühe waren mindestens einmal von stiller Brunst betroffen. Resonders häufig verliefen die ersten Ovulationen nach dem Einsetzen der zyktischen Ovaraktivität unerkannt. Bei stiller Brunst waren dabei die pheripheren Progesteronkonzentratwnen im Periöstrus signifikant höher als bei beobachteter Brunst. Dieses Phänomen war jedoch auf die ersten 5 Ovulationen p.p. begrenzt und weist auf hormonale, d.h. tierspezifische Ursachen der stillen Brunst in dieser Phase hin. Im weiteren Verlauf waren dagegen keine signifikanten Unterschiede in den Progesteronkonzentrationen zwischen stiller und beobachteter Brunst feststellbar. Damit müssen für die spätere p.p.-Phase eher managementbedingte Ursachen für die “stille” Brunst unterstellt werden. Während mit steigender Laktationsleistung die Häufigkeit anderer Fruchtbarkeitsprobleme lediglich tendenziell und nicht signifikant mit der Leistung korreliert anstieg, nahm bei höherer Milchleistung die Intensität von Brunstsymptomen deutlich ab. Damit traten stille Brunsten und Besamungen zumfalschen Zeitpunkt signifikant häufiser auf. Entsprechend läßt sich die Verlängerung der Zwischenkalbezeit bei steigender Laktationsleistung nahezu vollständig auf eine Zunahme stiller Brunsten und eine Häufung von Fehlbesamungen zurückführen. Neben der Milchleistung waren eine Reihe weiterer signifikanter Einflüsse auf die Fruchtbarkeit der Herde (z. B. Saison, Kalbenummer etc.) nachzuweisen. Der signifikant negative Einfluß steigender Milchleistung auf Fruchtbarkeitsparameter, insbesondere auf die Brunstsymptomatik, bestätigt sich jedoch auch nach Berücksichtigung dieser Einflußfaktoren im statistischen Modell. Contents: Influence of milk yield on the fertility of dairy cows post partum: evaluation of progesterone profiles Progesterone profiles were evaluated to monitor the influence of milk yield on fertility traits of dairy cows. The cows (n = 80) were kept under standardizised experimental farm conditions and progesterone was measured in milk fat during the post partum (p.p.) period. Overall, the most frequent fertility problem was a reduced intensity of oestrus symptoms and resulting drfficulties in heat detection and timing of artificial insemination (A. I.). 41.2% of all ovulations were not accompanied by observed heat symptoms (silent heat). 94.8% of the cows investigated were affected at least once during the p.p.-period by this problem. Silent heat was most frequent afer resumption of cyclic ovarian activity pp., In case of silent heat progesterone concentrations during perioestrus were significantly elevated compared to observed oestrus. This phenomenon was obvious up to the 5th ovulation p.p. indicating endocrine determinants of silent heat during this part of the pp. period. Thereafter progesterone concentrations during perioestrus were similar in case of both, silent and observed heat, indicating that during the late p.p. period silent heat is mainly due to management failure. The frequency of fertility problems in general tended to increase slightly but not significant with increasing milk yield. A significant adverse influence of increasing milk yield however was obvious for the intensity of oestrous symptoms. Consequently the frequency of silent heat and number of unsuccessful inseminations increased with advanced yield representing the main reason for increasing interval between calvings. Additionally other injluences on herd fertility were obvious (e.g. season, number of calving). The significant negative influence of increasing milk yield, particularly concerning oestrus intensity, could be confirmed even if these influences were eliminated by the statistical model.     

孕激素诱导的生长激素与犬的乳腺肿瘤

乳腺肿瘤是犬的最常见的肿瘤,约占母犬肿瘤总数的一半;乳腺肿瘤约有一半是恶性肿瘤,发生转移的比率很高。犬乳腺肿瘤的发病原因还不很明确,它的形成都受哪些因子调节还未完全确定。孕激素能够诱导乳腺组织生成并蓄积生长激素,使乳腺增生,最终导致犬乳腺肿瘤的形成。在此过程中,雌激素受体、孕激素受体、生长激素结合蛋白和生长激素受体在乳腺癌的形成、发展中起关键作用。从内分泌的角度对犬乳腺肿瘤发病机理作了简单综述,以期为激素治疗乳腺肿瘤提供一些理论依据。     

高原环境下母猎性发育与周期外周血中生殖激素水平

测定了拉萨高原环境下长白×内江（长内）、杜洛克×内江（杜内）母猪性发育期血中FSH、LH、E2与性周期血中FSH、LH、E2、P4的水平。45日龄时，长内、杜内母猪的FSH、LH均升高达到峰值，预示第1囊状卵泡出现于这一时期。性周期中，长内、杜内母猪之间LH、FSH、E2峰值均无明显的差异。长内、杜内母猪LH峰分别出现在周期0、1d；FSH峰分别出现在周期的13、17d，并分别在3、7d出现另一小峰，可能说明在母猪性周期中存在2个卵泡生长波；E2分别在周期的15、21d达到较大值。P4变化规律不明显，P4峰均产生于17d。     

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。     

陕西勉县奶牛布鲁氏菌病的血清学调查

通过对陕西勉县奶牛的布鲁氏菌病的血清学调查，掌握了该县布鲁氏菌病的疫情动态，为今后控制杜绝布鲁氏菌病的发生，提出畜间采取监测、检疫，淘汰阳性畜、免疫接种等防制方法，以及促进陕西勉县的畜牧业可持续发展提供了可靠的参考依据。     

Direct measurement of progesterone in plasma and milk by a simple solid-phase radioimmunoassay

A rapid method for determination of progesterone in bovine, goat and porcine plasma as well as in bovine milk was evaluated. The method employed was a solid-phase (125)I radioimmunoassay equipped with progesterone standards in human serum and called the Coat-A-Count procedure. The dilution curves of bovine plasma samples with high progesterone content were parallel with the standard curve based on human serum. The relation between measurements of progesterone levels in bovine plasma using the reference extraction method and the direct Coat-A-Count procedure was highly significant, resulting in the linear regression equation Y = 1.06x-0.04. In case of goat and porcine plasma, the direct method yielded higher results than the reference extraction method (Y = 1.37x + 1.38 and Y = 1.69x - 6.47, respectively). Progesterone concentration in bovine whole milk was much higher when measured by the Coat-A-Count procedure than by the reference Farmos kit (Y = 1.59x + 1.51). However, when the same samples were assayed by a modified Coat-A- Count procedure, i.e. progesterone standards from Farmos kit, the values were more or less identical (Y = 0.88x - 0.21).     

瘦素和FSH对绵羊卵泡颗粒细胞孕激素分泌的影响

试验旨在探明瘦素和卵泡刺激素(FSH)对绵羊卵泡颗粒细胞孕激素分泌的影响并建立瘦素和FSH之间的相互作用.从屠宰场收集健康母羊的卵巢,机械分离卵泡,收集卵泡颗粒细胞.在细胞培养液中加入不同浓度的FSH(0 U/mL,2.5 U/mL,5 U/mL,7.5 U/mL,10 U/mL)培养24 h和48 h,通过MTT检测...     

外源激素催乳对小牛泌乳的影响

利用外源激素刺激小牛泌乳的研究鲜有报道.研究对8月龄小牛进行外源激素注射,诱导小牛泌乳,并对催乳乳汁的乳脂、总蛋白、乳糖、干物质含量进行了分析.结果表明外源激素能有效刺激小牛泌乳,乳汁成分没有发生明显变化.这对快速鉴定转基因牛是否能生产活性蛋白具有一定意义.     

奶牛性控和常规冻精生产的F1代母牛产奶量和乳品质对比试验

从试验牛母亲人工授精开始,到试验牛第一个泌乳期结束,在所有条件相同的情况下,对性控和常规冻精生产的F1代母牛的泌乳量、乳脂率、乳蛋白率和体细胞数进行了比较,结果表明,性控冻精生产F1代母牛与同期常规冻精生产的F1代月产奶量和305d的产奶量,以及月平均和305d的平均乳脂率、乳蛋白率和体细胞数差异不显著(P>0.05);305d产奶量、平均乳脂率、乳蛋白率和体细胞数分别为9 419.64和9 494.44、3.62和3.62、3.15和3.18、40.64和41.70。说明性控冻精生产的F1代母牛与常规冻精生产的后代相比,泌乳性能未见异常。     

Priming with progestin, but not GnRH antagonist, induces a consistent endocrine response to exogenous gonadotropins in induced and spontaneously ovulating cats

Ovarian sensitivity to exogenous gonadotropin stimulation (equine chorionic gonadotropin [eCG] and human chorionic gonadotropin [hCG]) following pre-treatment with a progestin (levonorgestrel) versus GnRH antagonist (antide) was studied in cats known to be induced versus spontaneous ovulators. Queens were assigned to one of three treatments: (1) levonorgestrel implants+eCG/hCG (n=7 cats); (2) antide injections+eCG/hCG (n=7) or (3) eCG/hCG alone (control; n=7). Hormonal metabolites were assessed in fecal samples collected daily for 60 days before and during the 37 days inhibitory pre-treatment and for more than 60 days after eCG/hCG. Fecal metabolites of estradiol and progesterone were measured by radioimmunoassay. Females that maintained baseline progesterone were considered induced ovulators, whereas cats that exhibited a luteal phase before inhibition treatment were classified as spontaneous ovulators. Based on fecal hormone profiles, levonorgestrel thoroughly inhibited ovarian activity, whereas antide synchronized follicular phases but did not induce complete ovarian down-regulation. Both treatments prevented ovulation in spontaneous ovulators, but neither caused regression of existing corpora lutea (CL). Levonorgestrel, but not antide, pre-treatment resulted in a quiescent ovary at the time of eCG injection, yet endocrine responses to eCG/hCG were not different among treatments. Interestingly, spontaneously ovulating females exhibited a prolonged estradiol response to gonadotropin stimulation compared to induced ovulators, and this prolonged estradiol surge was replicated by levonorgestrel pre-treatment. Thus, the progestin levonorgestrel effectively suppresses follicular and luteal activity in the cat, resulting in a more consistent response to gonadotropin stimulation, even in females prone to spontaneous ovulation.     

绵羊实验性钼中毒研究Ⅷ.免疫指标的改变

成年健康绵羊投服无机钼15mg/(kg·d)即可引起免疫功能的损伤,同时加喂7g硫酸钠则能加剧免疫功能损伤。对钼中毒绵羊血液T、B淋巴细胞百分率及其绝对值和血清α_1、α_2、β、γ球蛋白含量的测定证实,超高水平的钼能导致血液B淋巴细胞百分率及绝对值降低,血清γ球蛋白含量下降;加喂硫酸钠不仅引起血液B淋巴细胞百分率及绝对值、血清γ球蛋白含量减少,而且可导致T淋巴细胞绝对值减少。