熊蜂（Bombus lucorum）微孢子虫的初步研究

在国内捕获野生的熊蜂(B.lucorum)蜂王,调查发现其微孢子虫的感染率为27.61%,死亡率为0.61%。在饲养过程中,感染严重的蜂王大多未能产卵就死亡,有的即使产了卵不久也便死亡;中度感染的蜂王大多推迟产卵;轻度感染的蜂王同健康蜂王一样能正常产卵。从熊蜂(B.lu-corum)蜂王提取的微孢子虫在光学显微镜下观察,呈卵圆状,带有蓝色折光;在扫描电镜下观察,孢子的表面较光滑,未发现任何特征型结构。     

熊蜂（Bombus terrestris）为温室黄瓜授粉的效果研究

通过对温室黄瓜应用熊蜂授粉和空白对照的比较研究,结果表明,熊蜂组的坐果率增加了33.5%,产量提高了29.4%,果实把柄长度降低了20.2%;而果实大小和含糖量、Vc含量、硝酸盐含量和亚硝酸含量,2组之间差异不大.说明熊蜂授粉可以促进温室黄瓜坐果,提高产量,降低果实把柄长度,但对果实的营养品质影响不大.     

熊蜂（Bombus spp.）的授粉特性及其人工饲养

本文通过对Bombus lucorum和Bombus terrestris两个熊蜂种的室内饲养及温室蔬菜授粉试验,分析了熊蜂的授粉特性、人工饲养技巧和应用前景.     

外来熊蜂可能对中国熊蜂资源造成的影响

熊蜂授粉技术是设施农业生产的重要配套技术,应用国外熊蜂授粉为中国设施农业授粉会带来很多问题,外来熊蜂有可能成为入侵生物,使我国的生态系统受到破坏;可能带来一些疫病或寄生虫,使我国养蜂业受到影响;还有可能通过杂交,发生基因改变,形成新的物种,破坏原有熊蜂资源;授粉业市场巨大,国家要花大量资金购买。呼吁国家管理部门尽快限制国外熊蜂进口,大力开发本土熊蜂资源,为我国设施农业授粉服务。     

环境温度对明亮熊蜂发育影响的研究

温度是影响明亮熊蜂发育的主要环境因素之一。在25~30 ℃范围内,随着环境温度的上升,明亮熊蜂的发育周期呈现缩短的趋势,蜂群成群率呈现上升的趋势,在29~30℃时,蜂王产卵时间、第一批卵虫蛹的发育日期和蜂群的成群时间最短,成群率最高。环境温度对蜂群所产生的蜂王数量也有着较大的影响,随着温度的上升,蜂王数量逐渐增加,在30℃时,蜂群所产生的蜂王数量最多。但温度对蜂群的工蜂数、雄蜂数和蜂王初生重没有影响。     

熊蜂授粉对温室草莓的影响研究

为了检验熊蜂为温室草莓授粉的效果,在温室内进行了熊蜂(Bombus lucorum)授粉试验,对照组为人工授粉.结果表明:与对照组相比,熊蜂授粉的草莓果实单果重达31.67g,比对照组增加了97.94%;果实的畸形果率为11.33%,比对照组下降了33.35%;熊蜂组的Vc含量为66.40 mg/100g,比对照组提高了19.00%,但在其它营养品质方面,两者之间的差异不显著.     

熊蜂的生物学观察及室内繁育

对野生熊蜂 Ｂｏｍｂｕｓｉｇｎｉｔｕｓ , Ｂｏｍｂｕｓ ｐｙｒｏｓｏｍａ 和Ｂｏｍｂｕｓ ｌｕｃｏｒｕｍ 种类的生物学进行了观察,同时对温室内引进种 Ｂｏｍｂｕｓｔｅｒｒｅｓｔｒｉｓ 的授粉生物学进行了观察,结合已掌握的文献资料进行分析研究,在室内已繁育成功 Ｂｏｍｂｕｓｌｕｃｏｒｕ ｍ , Ｂｏｍｂｕｓ ｉｇｎｉｔｕｓ 和Ｂｏｍｂｕｓ ｔｅｒｒｅｓｔｒｉｓ 三个种,为我国工厂化繁育熊蜂打下了良好的基础。     

猪配种过程中各环节的人工控制

1交配地点配种地点应保持干燥、卫生、不光滑。配种的公母猪最好大小相近,可在平坦的地面上进行配种,若公猪比母猪体小,配种时应选择斜坡地势,让公猪站在高处;若公猪比母猪个体大,可让公猪站在低处。若公猪体格很大,要防止母猪因公猪爬跨,而导致骨     

熊蜂对油茶授粉结实的影响初探

油茶为异花授粉植物,其产量与传粉昆虫关系密切,但油茶昆虫授粉问题一直未能得到有效解决,而熊蜂在温室大棚作物授粉方面具有效益高、品质好等优点.本文以普通油茶为研究对象,通过引进熊蜂对其进行授粉试验,分析熊蜂对油茶授粉结实的影响,以期为油茶的引蜂授粉研究和应用提供参考.试验结果表明,熊蜂的不同投放方式对油茶的座果结实有很大影响,熊蜂的自由式授粉、限制性授粉和自然昆虫授粉的座果率分别为36.78%、0.22%和18.23%,自由式授粉能显著提高油茶产量,而高饱和密度的限制性熊蜂释放方式反而会有减产作用;另外通过熊蜂授粉试验发现油茶不同亲本间的组配授粉结实率差异很大.因此在合理控制的情况下熊蜂能有效提升油茶产量.     

熊蜂微孢子虫感染熊蜂(Bombus spp.)试验

从引进蜂种(B.terrestris)和国内蜂种(B.lucorum)分别提取微孢子虫,在两寄主工蜂的幼虫,蛹和成蜂间进行交叉感染.结果显示两种来源的微孢子虫能相互感染其寄主蜂,且幼虫、蛹和成蜂两两间无显著差异;用国内蜂种(Blucorum)提取的微孢子虫感染四种熊蜂(B.lucorum,B.pyrosoma,B.ignitus,B.terrestris),结果显示出同一种寄主提取的微孢子虫感染不同蜂种,对原寄主的感染率高于异源寄主,但死亡率低于异源寄主,不同来源的微孢子虫对不同寄主熊蜂感染程度的不同,是不同基因型的寄主群和不同基因型的寄生群间相互影响的结果.     

云南蒙自持续干旱对西方蜜蜂蜂王交尾成功率的影响

2010年4月21日～7月19日在蒙自县城周围和草坝镇的西方蜜蜂蜂场进行了西方蜜蜂交尾成功率试验。结果表明,蒙自县城周围蜂场的西方蜜蜂交尾成功率为75%,草坝镇蜂场的西方蜜蜂蜂王交尾成功率平均为19.98%。因此认为持续干旱对西方蜜蜂养殖影响很大。     

Dominance and mating behavior of rams under paddock conditions

Contents A total of 30 ewes in three-sire or four-sire breeding pens were observed continously during daylight for four consecutive days of a synchronised estrus period. A linear dominance hierarchy was observed between the rams which was consistent and stable for each observation period. The highest ranking ram had more mounting encounters and was more aggressive than the subordinate rams. This activity disturbed his ejaculatory mechanism and sometimes resulted in the absence of ejaculation or energetic ejaculation. In the four-sire breeding pens the dominant ram often found it impossible to completely curtail the sexual activity of the subordinate rams. He made 70.9% and 49.0% of the total number of mounts in the three-sire and our-sire breeding pens, respectively. At the beginning of each observation period the highest ranking ram claimed most estrous ewes for his “harem”. The subordinate rams only had an opportunity to mate when several ewes were simultaneously in estrus. The average number of mounts per first copulation per ram was 2.2 (range 1.3–3.1). The time spent from first contact with the ewes until completion of the copulatory act in first copulation varied from 0.2–16.2 min. with an average of 4.0 min., whereas this interval was increased during the second copulation (average = 5.8 min.). Furthermore, the mating behavior of single rams was also observed. Inhalt: Rangordnung und Paarungsverhalten von Schafbocken unter Stallhaltungsbedingungen Es wurden insgesamt 30 Mutterschafe in Zehnergruppen mit 3 bzw. 4 Böcken gleichzeitig in einer Buchte gehalten und wahrend einer Östrusperiode tagsüber beobachtet. Fur die Böcke konnte eine klare Rangordnung erkannt werden, die über alle Beobachtungsperioden unverändert blieb. Der an höchster Stelle stehende Bock vollzog mehr Aufsprungsversuche und war aggressiver als die untergeordneten Böcke. Diese Aktivitäten störten bei ihm wiederholt den Ejakulatonsmechanismus, so daß ein unvollständiger Deckakt bei fehlender Ejakulation die Folge war. Bei gleichzeitiger Anwesenheit von 4 Böcken in einer Gruppe way es für den dominanten Bock häufig unmöglich, die Sexualaktivität der untergeordneten Böcke vollständig zu unterbinden. Auf den dominanten Bock entfielen bei Anwesenheit von 3 Böcken 70,9% aller Auf sprünge, bei der Anwesenheit von 4 Böcken waren dies 49,0%. Zu Beginn einer jeden Beobachtungs-periode versuchte der an höchster Stelle rangierende Bock, die meisten östrischen Mutterschafe für seinen “Harem” zu beanspruchen. Die untergeordneten Böcke hatten nur dann Gelegenheit zu decken, wenn mehrere Mutterschafe gleichzeitig im Östrus waren. Im Durchschnitt betrug die Anzahl der Auf sprünge bei der ersten Belegung pro Bock 2,2 (Schwankungsbreite 1,3 -3, 1). Die erforderliche Zeit fur die erste Paarung uariierte bei einem Mittelwert uon 4,0 Alin. zwischen 0,2 und 16,2 Min.; diese Zeitspanne erhöhte sich allerdings für die zweite Belegung auf durchschnittlich 5,8 Min. Darüber hinaus wurde das Paarungsuerhalten einzelner Böcke ohne die Anwesenheit anderer beobachtet.     

熊蜂为温室西红柿授粉的效果研究

通过对温室西红柿应用熊蜂授粉、人工喷施激素和空白对照的比较研究 ,表明熊蜂组在产量上比激素组和对照组分别增加了 5 9 2 6 %和 142 15 % ,而畸形果率却分别下降了 6 7 41%和 83 6 8% ,利用熊蜂授粉还可以缩短果实成熟期 ,提高维生素C含量和总糖含量 ,降低酸度 ,改善果实品质。     

海拔对高山植物交配系统的影响

交配系统是控制遗传物质在世代间传递的直接方式,影响着植物种群内和种群间遗传变异分布,决定着后代种群的遗传结构和遗传多样性。交配系统除了体现植物本身的生物学特性之外,还因环境条件的改变而发生改变和进化。海拔对环境因子在垂直方向上分布的影响呈现出一定的规律性,因而影响着植物的交配系统。对交配系统的进化模式研究发现,随着海拔的升高交配系统有从异交向自交演变的倾向,甚至在极端环境下植物的进化产生多倍体以适应恶劣的环境条件。本研究根据大量已有的研究成果,从海拔影响植物交配系统的传粉者数量、区系、传粉方式、植物生活史、花朵构件等方面进行了总结和概述。     

长白山熊蜂与中、西蜂的遗传学研究

应用八组随机引物：W1（5’－CGGCCCCTGT－3’），W2（5’CGGCCCCGGT－3’），W3（5’－CGAGGCTTCT－3’），P7（5’－CACCGATCCA－3’），P8（5’－CCCACCCTTG－3’），P11（5’－ACACAGAGGG－3’），P12（5’－TCACCGTGTC－3’），P13（5’－GACAAGGACC－3’），分别对熊蜂、中蜂、西蜂提取纯化DNA基因组经RAPD－PCR技术进行遗传学研究。结果：获得熊蜂DNA基因组多态性图谱及熊蜂与中、西蜂DNA基因组多态性的鉴别图谱。     

The effect of individual liveweight and condition scores of ewes at mating on reproductive and scanning performance

Abstract

AIMS: To determine the effects of liveweight (LW) and condition score (CS) of ewes at mating on both mating performance and scanning percentage, and to determine if effects of CS were independent of LW.

METHODS: Two groups of ewes, comprising 1,780 mixedaged Romney (Rom MA) and 692 composite two-tooth (? East Friesian 1/16 Finn 13/16 Romney, Comp TT) ewes were grazed separately with harnessed rams for two reproductive cycles. Romney rams were used for the first 17 days of mating and then replaced on the morning of Day 18 by Suffolk rams. Ewes were weighed and CS assessed on a scale of 0–5 before the introduction of the rams. Ewes were identified as having been mated during the first cycle only, during both cycles, during the second cycle only, or not mated. All mated ewes were scanned using ultrasound, 50 days after the end of mating, and identified as being either non pregnant, single-, twin- or triplet-bearing.

RESULTS: Linear relationships (R²=0.99) between mean LW and CS at mating were evident for both Rom MA and Comp TT ewes and the mean increase in LW per unit increase in CS was greater in the Rom MA ewes (7.88 kg) than the Comp TT (4.78 kg) ewes (p<0.05). Ewes mated in the second cycle only were significantly (p<0.05) lighter than those mated in the first cycle only. In Rom MA ewes, a greater proportion were mated in the first cycle only if CS was .2.0 than if CS was <2.0, and the proportions of ewes mated in the first cycle only or in both cycles did not differ if CS was ≥2.5. In Comp TT ewes, there was no difference in the proportions mated in the first cycle or both cycles, if CS was ≥2.0. Triplet-bearing ewes were heavier than twin-bearing ewes, which were in turn heavier than both singleton-bearing and non pregnant ewes. Twin-bearing ewes had higher CS than both single-bearing and non pregnant ewes (p<0.05) but differences were not significant if LW was included as a covariate. In both Rom MA and Comp TT ewes, greater proportions were non pregnant and lower proportions had twins if CS was <2.0 than if CS was ≥2.0. In Rom MA ewes only, a greater proportion again had twins and a lower proportion had singletons if CS was ≥3.0 than if CS was <3.0. In Comp TT ewes, the proportion that were non pregnant or twin-bearing did not vary with CS if CS was ≥2.0. Reproductive performance was maximal for Rom MA and Comp TT ewes that had CS at mating ≥3.0 and ≥2.0, respectively, equating to LW of 62.6 and 48.5 kg, respectively.

CONCLUSIONS: In both groups of ewes, CS and LW at mating positively affected reproductive performance measured at the time of mating and at scanning, however, no reproductive advantage was evident above a minimum CS of 3.0 and 2.0, equating to LW of 62.6 and 48.5 kg, for Rom MA and Comp TT ewes, respectively. Sheep farmers should direct management to ensure that no ewes are below these minimum targets rather than ensuring high average LW and/or CS of a mob.     

Optimization of selection and mating schemes in closed broiler lines

Minimum coancestry mating (MC) is a simple mating system to reduce inbreeding in populations, in which matings are allocated so as to minimize the average inbreeding coefficient of progeny. This system was compared with random mating (RM) in simulated broiler lines. The population structure and genetic parameters were determined on the basis of an existing broiler line. Comparison of mating systems was made under two selection methods. The first method (DIS) was based on selection index for achieving desired genetic gains. In the second method (LPS), a combination of the family index and linear programming technique was applied to obtain the desired genetic gains. The selected traits were body weight at 6 weeks of both sexes and age at sexual maturity of hen. Four schemes by all the possible combinations of selection and mating methods (DIS + RM, DIS + MC, LPS + RM and LPS + MC) were compared in terms of genetic gains and inbreeding during 15 generations of selection and mating. The results obtained are summarized as follows: (i) the four schemes produced similar genetic gains averaged over replicates; (ii) the variations of genetic gains under LPS + RM and LPS + MC schemes were much smaller than under DIS + RM and DIS + MC schemes; (iii) irrespective of the selection methods, MC reduced the average inbreeding coefficients to about 80% of RM and; (iv) the inbreeding coefficients of individuals in the schemes with RM were distributed in a wide range, while the inbreeding coefficients in the schemes with MC showed a high uniformity. From these results, the LPS + MC scheme was recommended as a selection and mating strategy in closed broiler lines.