The growing prevalence of Nosema ceranae in honey bees in Spain, an emerging problem for the last decade

Microsporidiosis caused by infection with Nosema apis or Nosema ceranae has become one of the most widespread diseases of honey bees and can cause important economic losses for beekeepers. Honey can be contaminated by spores of both species and it has been reported as a suitable matrix to study the field prevalence of other honey bee sporulated pathogens. Historical honey sample collections from the CAR laboratory (Centro Apícola Regional) were analyzed by PCR to identify the earliest instance of emergence, and to determine whether the presence of Nosema spp. in honey was linked to the spread of these microsporidia in honey bee apiaries. A total of 240 frozen honey samples were analyzed by PCR and the results compared with rates of Nosema spp. infection in worker bee samples from different years and geographical areas. The presence of Nosema spp. in hive-stored honey from naturally infected honey bee colonies (from an experimental apiary) was also monitored, and although collected honey bees resulted in a more suitable sample to study the presence of microsporidian parasites in the colonies, a high probability of finding Nosema spp. in their hive-stored honey was observed. The first honey sample in which N. ceranae was detected dates back to the year 2000. In subsequent years, the number of samples containing N. ceranae tended to increase, as did the detection of Nosema spp. in adult worker bees. The presence of N. ceranae as early as 2000, long before generalized bee depopulation and colony losses in 2004 may be consistent with a long incubation period for nosemosis type C or related with other unknown factors. The current prevalence of nosemosis, primarily due to N. ceranae, has reached epidemic levels in Spain as confirmed by the analysis of worker honey bees and commercial honey.     

Rapidly quantitative detection of Nosema ceranae in honeybees using ultra-rapid real-time quantitative PCR

BackgroundThe microsporidian parasite Nosema ceranae is a global problem in honeybee populations and is known to cause winter mortality. A sensitive and rapid tool for stable quantitative detection is necessary to establish further research related to the diagnosis, prevention, and treatment of this pathogen.ObjectivesThe present study aimed to develop a quantitative method that incorporates ultra-rapid real-time quantitative polymerase chain reaction (UR-qPCR) for the rapid enumeration of N. ceranae in infected bees.MethodsA procedure for UR-qPCR detection of N. ceranae was developed, and the advantages of molecular detection were evaluated in comparison with microscopic enumeration.ResultsUR-qPCR was more sensitive than microscopic enumeration for detecting two copies of N. ceranae DNA and 24 spores per bee. Meanwhile, the limit of detection by microscopy was 2.40 × 10⁴ spores/bee, and the stable detection level was ≥ 2.40 × 10⁵ spores/bee. The results of N. ceranae calculations from the infected honeybees and purified spores by UR-qPCR showed that the DNA copy number was approximately 8-fold higher than the spore count. Additionally, honeybees infected with N. ceranae with 2.74 × 10⁴ copies of N. ceranae DNA were incapable of detection by microscopy. The results of quantitative analysis using UR-qPCR were accomplished within 20 min.ConclusionsUR-qPCR is expected to be the most rapid molecular method for Nosema detection and has been developed for diagnosing nosemosis at low levels of infection.     

Stable gastric pentadecapeptide BPC 157 in honeybee (Apis mellifera) therapy,to control Nosema ceranae invasions in apiary conditions

Nosema ceranae can cause major problems, such as immune suppression, gut epithelial cell degeneration, reduced honeybee lifespan, or suddenly colony collapse. As a novel approach in therapy, we hypothesize the stable gastric pentadecapeptide BPC 157 in honeybee therapy, to control N. ceranae invasions in apiary conditions: BPC 157 treated sugar syrup (0.25 L sugar syrup supplemented with 0.1 μg/ml BPC 157), as well as the pure sugar syrup (0.25 L sugar syrup; control), was administered to honeybee colonies in feeders situated under the roof of the hives, during 21 consecutive days, at the end of beekeeping season. The strength of honeybee colonies was increased 20 and 30 days after initial feeding with BPC 157 supplement (Day 1, 36.100 ± 698; Day 20, 64.860 ± 468; Day 30, 53.214 ± 312 estimated number of honeybees), in field conditions. The similar successful outcome occurs with the N. ceranae spore loads counted in the homogenates of sampled adult honeybees (Day 1, 6.286 ± 2.336; Day 20, 3.753 ± 1.835; Day 30, 2.005 ± 1.534 million spores/bee). Accordingly, with the noted increased strength of the colonies fed with sugar syrup supplemented with BPC 157, the number of N. ceranae spores per honeybee gradually decreased as well. Besides, honeybees infected with N. ceranae fed with sugar syrup exhibited severe damage of midgut wall layers and epithelial cells. By contrast, in honeybees infected with N. ceranae fed with sugar syrup supplemented with BPC 157, all damages were markedly attenuated, damages of the outer muscular coat, in particular. In conclusion, the results of the first field trial on diseased honeybee colonies with BPC 157 indicate significant therapeutic effects with the used oral therapy with BPC 157 supplementation.     

Emerging and re-emerging viruses of the honey bee (Apis mellifera L.)

Until the late 1980s, specific viral infections of the honey bee were generally considered harmless in all countries. Then, with the worldwide introduction of the ectoparasite mite Varroa destructor, beekeepers encountered increasing difficulties in maintaining their colonies. Epidemiological surveys and laboratory experiments have demonstrated that the newly acquired virulence of several viruses belonging to the family Dicistroviridae (acute bee paralysis virus, Kashmir bee virus and Israeli acute paralysis virus) in Europe and the USA had been observed in relation with V. destructor acting as a disseminator of these viruses between and within bee colonies and as an activator of virus multiplication in the infected individuals: bee larvae and adults. Equal emphasis is given to deformed wing virus (DWV) belonging to the Iflaviridae. Overt outbreaks of DWV infections have been shown to be linked to the ability of V. destructor to act not only as a mechanical vector of DWV but also as a biological vector. Its replication in mites prior to its vectoring into pupae seemed to be necessary and sufficient for the induction of a overt infection in pupae developing in non-viable bees with deformed wings. DWV in V. destructor infested colonies is now considered as one of the key players of the final collapse. Various approaches for combating bee viral diseases are described: they include selection of tolerant bees, RNA interference and prevention of new pathogen introduction. None of these approaches are expected to lead to enhanced bee-health in the short term.     

黑蜂王台病毒研究进展

黑蜂王台病毒(black queen cell virus,BQCV)是一种常见的蜜蜂病毒,春季和初夏高发,主要危害蜂王的幼虫和蛹,蜜蜂患病后短时间内死亡,王台壁进而变黑。黑蜂王台病毒已在世界不同蜂种间广泛传播,常以无明显症状的隐性感染方式存在于蜂群中,与蜜蜂微孢子虫联合危害表现出极强的致病性,对养蜂业造成巨大损失。作者从黑蜂王台病的病原学、流行病学、临床症状、致病过程、检测方法及防控方面对其研究进展进行综述,为进一步研究黑蜂王台病毒及其防制措施提供参考。     

Research Advance on Black Queen Cell Virus

Black queen cell virus(BQCV) is a common bee virus, usually outbreaks in spring and early summer, and mainly infects bee larvae and pupae, the bees will die within a short time after illness, at last, the queen cell walls turn black.BQCV has been widely spread among different bee species in the world, often exists in the colonies with no obvious symptoms of inapparent infection, shows strong pathogenicity coinfection with bees Nosema, and causes huge losses to the beekeeping.We summarized the current research on etiology, epidemiology, clinical symptoms, pathogenic processes, diagnostic techniques, prevention and control of BQCV infection, so as to provide a reference for further study of BQCV and prevention and control methods.     

患白垩病蜂群的温湿度研究

以蜜蜂白垩病致病菌蜜蜂球囊菌(Ascosphaera apis)感染西方蜜蜂(Apis mellifera).通过记录染病蜂群的温湿度和发病幼虫数,研究了养蜂生产中,温湿度变化对感染该病的西方蜜蜂蜂群(中等群势)的影响.结果显示:当蜂群内的温度降低到某个阈值范围时,不论是试验组还是对照组都会出现不同程度地增加发病幼虫数.     

新疆尼勒克县种蜂场小蜂螨给蜂农养蜂造成沉重打击

2013年，新疆尼勒克养蜂受到了小蜂螨的危害，加之采蜜季节阴雨天气过多，导致蜂农养蜂受到沉重打击，给新疆尼勒克养蜂生产造成了很大影响，同时也对新疆黑蜂的保种、育王等工作造成一定的困难。针对这样的病害，新疆伊犁州尼勒克县种蜂场蜂业有关人员联系蜂农，讨论并制定了一系列的措施来预防下一年螨害继续危害新疆伊犁州尼勒克县种蜂场蜂群。     

Occurrence of acute paralysis virus of the honey bee (Apis mellifera) in a Hungarian apiary infested with the parasitic mite Varroa jacobsoni.

Viruses of the honey bee have been known for a long time; however, recently the attention of scientists and apiculturalists has turned towards the relationship between these viruses and the parasitic mite Varroa jacobsoni. Although clinical symptoms indicated the presence of some of the viruses of bees in Hungary, none have previously been isolated or identified. During July unusual adult bee and brood mortality was observed in some colonies of an apiary in Budapest known to be infested with Varroa jacobsoni. Large amounts of acute paralysis virus (APV) were detected serologically in healthy honey bee pupae killed by the injection of a bacteria-free extract of diseased adult bees. Crystalline arrays of 30 nm particles were seen in ultrathin sections of the tissues of injected pupae and naturally infected adult bees. In spite of the application of acaricide treatments the bee population in several colonies had collapsed by the end of summer and the apiary suffered severe wintering losses.     

Efficacy of silver ions against Sacbrood virus infection in the Eastern honey bee Apis cerana

Although silver is known to be a broad-spectrum biocidal agent, the effects of this metal against Sacbrood virus have not yet been investigated. In this study, we evaluated the efficacy of silver ions against natural Korean sacbrood virus (KSBV) infection of Apis (A.) cerana. Ten KSBV-infected colonies containing A. cerana with similar strength and activity were selected from an apiary located in Bosung-gun (Korea). Among these, five colonies were randomly assigned to the treatment group that was fed sugar syrup containing 0.2 mg/L silver ions. The other colonies were assigned to the untreated control group in which bees were given syrup without the silver ions. To assess the efficacy of the silver ions, colony strength, colony activity, and the number of dead larvae per hive were measured. During the experimental period, the test group maintained its strength and activity until day 32 while those of bees in the control group decreased sharply after day 8 to 16. Survival duration of the test group was significantly longer (40 days) than that of the control group (21 days). These results strongly indicated that silver ions are effective against KSBV infection in A. cerana.     

A comparison of the effectiveness of the microscopic method and the multiplex PCR method in identifying and discriminating the species of Nosema spp. spores in worker bees (Apis mellifera) from winter hive debris

The objective of this study was to compare the effectiveness of the multiplex PCR method and traditional light microscopy in identifying and discriminating the species of Nosema spp. spores in worker bees from winter hive debris in the Province of Warmia and Mazury (NE Poland). A total of 1000 beesdead after from the bottom of the hive from bee colonies were analyzed. Spores were identified with the use of a light microscope (400-600x magnification). Spores were assigned to species by the multiplex PCR method. The microscopic evaluation revealed the presence of Nosema spp. spores in 803 samples (80.3%). Nosema ceranae spores were observed in 353 positive samples (43.96%), Nosema apis spores were found in 300 samples (37.35%), while 150 samples (19.67%) showed signs of a mixed infection. A multiplex PCR analysis revealed that 806 samples were infested with Nosema spp., of which 206 were affected only by Nosema ceranae, 600 showed signs of mixed invasion, while no samples were infected solely by Nosema apis parasites. In two cases, the presence of spores detected under a light microscope was not confirmed by the PCR analysis. The results of the study indicate that Nosema ceranae is the predominant parasitic species found in post-winter worker bees from the bottom of the hive in the region of Warmia and Mazury.     

Beekeeping management practices in southwestern Quebec

The growing number of honey bee colonies and beekeepers in Canada has led to a great diversity of beekeeping practices. All beekeeping operations, however, need to implement consistent management measures for the control of diseases. The objective of this study was to document the actual disease management practices of beekeeping productions in southwestern Quebec, Canada. A survey was conducted to describe management practices used by 15 beekeepers who own 1824 colonies in that area. Data were obtained by telephone interviews. When infectious diseases were suspected, beekeepers generally avoided using potentially toxic acaricides and chemical treatments associated with antimicrobial resistance and instead used preventive, physical or management methods, although laboratory diagnosis was rarely used. This study highlights the wide variety of operation sizes, activities, and disease management strategies among beekeepers in southwestern Quebec. It identifies the need to encourage the use of services available to them and to propose a standardized preventive medical approach for field veterinarians to avoid the spread of infectious diseases.     

在工蜂产卵超过23天的中蜂群中介绍蜂王

在中蜂的饲养管理中,蜂群失王且工蜂产卵后,一般处理方法都是并入它群;实验是在不得已的情况下,将3群失王且工蜂产卵超过23 d的中蜂群合并的同时,介绍蜂王获得成功.     

蜂群的雄蜂培育规律及其对蜂群影响研究初探

雄蜂是三型蜂的重要组成部分,在蜂群中承担着与处女王交配繁殖后代等重要作用.为研究蜂群培育雄蜂的规律,探明养蜂实践中限制雄蜂数量是否对蜂群发展产生影响,设置试验组(割除雄蜂蛹)与对照组试验蜂群,观察蜂群培育雄蜂情况及其对蜂群的影响.结果 表明:蜂群中培育雄蜂不随人为干预而改变,人为限制雄蜂发展会导致蜂群接受外来雄蜂,人为...     

吉林省蜜蜂产业发展调研报告

吉林省蜜粉源、蜂种和科技资源丰富,扶贫成效显著,适合大力发展养蜂产业。通过对吉林省境内蜂产业调研,基本掌握了蜂群饲养、养殖户、蜂业组织发展、蜂产品企业、授粉产业发展等情况,对现存问题进行分析和探讨。     

Vertical transmission of American foulbrood (Paenibacillus larvae) in honey bees (Apis mellifera)

The mode of transmission between hosts (horizontal versus vertical) of disease agents is important for determination of the evolution of virulence in pathogens. For disease management, it is imperative that the epidemiology of the disease is understood and pathogen transmission rates between hosts is a key factor for this understanding. Surprisingly little is known about transmission rates in honey bee pathology. We have studied the rate of vertical transmission of Paenibacillus larvae, the causative agent of American foulbrood (AFB) in honey bee colonies, as colonies reproduce by colony fission (swarming), by culturing for the spores from repetitive samples of adult bees. The results demonstrate vertical pathogen transmission to daughter swarms. The spore density declines over time in both mother colonies and daughter swarms if mother colonies do not exhibit clinical disease symptoms. Occasional positive samples more than a year post swarming, also in daughter swarms, indicate production of infectious spores from diseased larvae, without clinical disease observable by beekeepers, and/or maintenance of infective spores in the hive environment, allowing both horizontal and vertical transmission to be maintained. The results suggest that the virulence of AFB, being lethal at colony level in contrast to other bee diseases shaped by evolution, could be dependent on apicultural practices and that the pathogen probably would be maintained without causing frequent colony mortality in a natural system.     

The effects of hive types (shield and sword) on wintering ability,survival rates and strength of honeybee colonies (<Emphasis Type="Italic">A. mellifera</Emphasis> L.) in spring season

This study was carried out to determine the effects of shield and sword comb orientation hive types on wintering ability, survival rates (in winter) and population growth of honeybee colonies (A. mellifera anatoliaca) in spring season. In ancient Anatolia beekeeping; honeybee colonies were identified sword and shield (the colonies which build up the combs vertical and horizontal according to positions of the hive entrance) before the uses of top-opened hive with movable frames. Total twenty honeybee colonies, which have similar condition according to queen age, genotype, number of frames covered with adult worker bees, brood areas and food stocks, were used in this study. Average wintering ability of colonies in the shield and sword groups were found to be 98.57% and 69.76%; average survival rates were found to be 100% and 100% in shield and sword group colonies respectively. The average number of frames covered with adult worker bees at mid June in shield and sword group colonies were found to be 15.6 ± 1.58, 12.00 ± 1.25 number/colony and the average brood areas were found as 7863.5 ± 402.9, 5997.0 ± 373.3 cm²/colony respectively. Differences between the group means on wintering ability, sealed brood areas and colony strength were found significant (P < 0.01), but differences on survival rates were not found significant (P > 0.05). The colonies living in shield (horizontal) hives have showed better wintering ability and more colony population than colonies living in sword (vertical) hives.     

以随机扩增多态性DNA(RAPD)技术筛选意大利蜜蜂重要农艺性状遗传标记

为了获得意大利蜜蜂重要农艺性状的分子遗传标记 ,本研究以 30种RAPD随机引物对平湖浆蜂、美意、澳意、苏意等 4个在产浆、采蜜和抗病性上存在较大差异的意蜂品系的基因组DNA进行RAPD_PCR扩增筛选。试验结果显示 ,随机引物W 1 8(5′_CGGACGGCGG_3′)和W2 3(5′_GTACCGCCCG_3′)的扩增图谱呈多态性。其中 ,在引物W 1 8所扩增出的 9条片断中 ,2 35 2bp和 36 4bp条带为美意所特有 ,表明可将之用于鉴别美意 ;2 0 92bp条带仅出现于蜂蜜高产的美意和澳意中 ,意味着该条带为一个蜂蜜高产性状的遗传标记 ;而 6 32bp条带在王浆高产品系平湖浆蜂中出现的频率 (0 91 )显著高于 (P <0 0 1 )美意(0 0 4 )、澳意 (0 0 2 )和苏意 (0 0 0 ) ,说明 6 32bp条带可能为王浆高产性状的一个遗传标记。在W2 3引物扩增条带中 ,6 5 1bp条带为澳意所特有 ,可用于澳意鉴别     

用改造式蜂箱饲养中蜂的研究报告

通过通过箱体、实行中蜂贮蜜与繁殖分区管理，解决流蜜期繁殖与贮蜜的矛盾，发挥蜂群繁殖与采集的积极怀，增加蜂蜜的产量，获得纯正的成熟蜂蜜。三个阶段的试验结果表明：中蜂改造式蜂箱与中蜂标准箱、即氏蜂箱相比每群平均多增蜂１．０框，多造牌０．３和，越冬蜂损失少０．２框，提高蜂蜜产量３０％以上，增加浓度１－２Ｂｅ，中囊病病情指数低１３．２％。     

2007～2008年转地蜂场养蜂生产成本调查

对浙江省缙云县80家转地蜂场养蜂生产成本进行了调查,结果表明:2008年养蜂生产总成本598.45元/群,比2007年增长14.22%。2007～2008年转地蜂场年平均生产总成本561.19元/群,与2005～2006年相比,增长6.36%。2007年和2008年,养蜂生产总成本分别占总收入的72.62%和78.72%。转地蜂场生产成本高,尤其是运费开支。蜜蜂授粉对生态农业的发展起到了巨大的作用,促进了农业的增产。养蜂业亟需政府的关注和支持。