6th Brazilian Encontro and 8th International Conference on Tropical Bees; Parts I – III
American Bee Journal (May, July, August 2005), Vol. 145
Malcolm T. Sanford
In my series on the current status of Brazilian beekeeping I mentioned that
the Africanized honey bee’s introduction into that country produced a huge
outpouring of scientific study. The
result of this continues to be the legacy of one of the world’s most dynamic
faculties involved with tropical bees at the
According to Dr. Lionel Gonçalves writing in the
preface to the sixth Encontro held September 6-10,
The recent Encontro commemorated the 40th
anniversary of the Faculty of Philosophy, Science and letters at the
Four presentations comprised the beginning plenary session, in a sense setting the tone for the event. Two were by those who were honored at the fourth Encontro, Drs. Kerr and Nogueira Neto. Professor Kerr, who though he is now 82 years old, still works full time at the Federal University of Uberlândia in Minas Gerais, discussed the differences between (Melipona) tropical bees and (Apis) honey bees beyond the presence or absence of a sting apparatus. . It turns out that Melipona workers more resemble males than queens, and the male bees actually do work in the nest. Young Melipona virgins leave the nest during swarming instead of the old queen as in Apis, and only mate with one male instead of 10 to 30 normally associated with honey bees. Finally, Melipona species have from 8 to 20 pairs of chromosomes, whereas Apis has a constant 16. Dr. Kerr suggested that the variablility in Melipona chromosome number may result from a fracturing or breaking of extant chromosomes. Most likely they are those involved in determining caste (drone, queen, worker), providing an explanation for the differences between Apis and Melipona bees noted above.
Dr. Nogueira Neto
discussed the current status of the culture of Melipona
bees from the developing of nests with movable frames to a pump for sucking the
honey out of the honey “pots” the bees make.
They do not store honey in combs like Apis
bees. He emphasized that the honey from Melipona is substantially different and commands a
higher price than that collected from Apis. He suggested a new name for this sweet, “iramel,” taken from the indigenous name of the stingless bee (ira) and
Portuguese word for honey (mel). A problem in
Dr. Carminda de Cruz Landim and associates reported on the differences in pheromone-producing glands between stingless (Melipona) and Apis bees. These are found almost anywhere on the body; suggesting that both types bees can be characterized as a flying “collection of glands.” The authors presented a chart revealing what is known about the glands present in both kinds of social bees. These include: Nassanov (on the abdomen), Koschewnikov (inside, near the sting apparatus), tergal (just below the exoskeleton ), tarsal (in the foot), mandibular (around the mouth), Dufour (near the sting apparatus - producing the “alarm” substance) and labial (near the mouth). Most of these produce substances that are volatile and diffuse into the air, making them difficult to collect and employ in experiments, and this is the reason many have not yet been identified in either kind of bee.
Dr. Wolf Engels asked “What bee larvae might tell their nurses,” by “taking a look into a superfamily with a lot of kids”. Communication is necessary, given the highly evolved progressive brood feeding found in honey bees (Apis). The larvae are monitored continually, and their nutritional needs are determined by workers on each visit. Sick or parasitized larvae are also detected and eliminated from the colony in the process. This results from a “larval cry” to “feed me or remove me.”
A prime example of the “remove me” or “eat me” command is found in a colony’s disposition of diploid drone larvae. These individuals are produced by inbred Apis queens, which lay many fertilized eggs with two identical alleles at a specific spot, called a “locus,” (the one determining sex) on a chromosome. Males are normally haploid, but diploid individuals that have two copies of the same sex allele also become males. They are eaten by workers on the first day of life after hatching from the egg, causing the colony to have to produce a replacement. Up to fifty percent of the larvae may be affected, weakening a colony through what is called “inbreeding depression.” The removal behavior does not extend to second- or third-day larvae, but by that time all the diploid drones have been eaten. Melipona species are not as good as Apis in searching out these larvae, however, and so whereas not one survives in the latter bee species, many appear to do so in the former.
The signal produced by diploid drones is not a “cannibalism substance,” Dr. Engels stated, as originally thought by some investigators. It is recognition that the skin surface (made up of complicated hydrocarbons) is different from that of normal larvae.
By contrast, the larval feeding cry is a volatile substance (brood pheromone) put out by the grubs and recognized by workers. The chemical must last for a period of time, as not all visiting workers have the correct food supply. Thus, Dr. Engels concluded this “budgeting system” allows workers to feed larvae on demand and only when necessary, “an amazing masterpiece of social evolution.”
In a symposium on Apis biology, Dr. David De Jong, a former
Most human management concentrates colonies, which works against the production of disease-resistant bees, according to Dr. De Jong. So does forcing bees to use wax foundation, moving them to different areas, exposing hives to chemical treatments, and replacing queens. Requeening is perhaps the most important undertaking of the beekeeper, yet often receives little of the care it deserves in either the rearing of individual queens or introducing them into colonies. Not only does changing the queen introduce different genes, but it also provides a needed “break in the brood cycle.” This provides time for affected individuals to be removed, especially known to help in cases of European foulbrood. In general it can be concluded that many apparent “problems” in bee colonies are provoked by old and failing queens. Thus, replacing them regularly can often be considered a uniform solution to a myriad of conditions.
Varroa mite infestation is also increased in
colonies that are closer together, as is the potential for other diseases like
American foulbrood. This is because weak
colonies become reservoirs for parasites and diseases that then are easily
spread to nearby hives by robbing or drifting bees. Development of susceptible colonies is
encouraged by beekeepers using both antibiotics for bacterial control and
chemicals to lower mite populations. One
of the lessons of
When looking at how honey bees resist diseases and parasites, one cannot
ignore the effect of cell size, Dr. De Jong
concluded. There is some anecdotal
evidence that this can play a significant role in colony health, but little
formal research to confirm the idea.
Other papers on honey bee pathology revealed the current situation with
respect to Varroa mite classification, antibiotic use
in bacterial control, and detection and transmission of bee viruses. Dr. Denis Anderson from
The antibiotic Terramycin® formulated from oxytetracycline hydrochloride for the control of the
foulbroods in the
Precisely because the honey bee has become such a successful species in
1. Monitoring pollinator decline and its effect on commercial agriculture.
2. Addressing the lack of classification information on native pollinators.
3. Promoting conservation, restoration and sustainable use of native pollinators.
The Brazilian Pollinators Initiative (BPI) has transformed into and
International Pollinators Initiative (IPI) and has a World Wide Web presence
<http://www.webbee.org.br>. Other papers in the symposium on pollinator
initiatives included monitoring the spread of non-native bumble bees (Bombus ruderatus)
A related symposium discussed the incredible bee diversity in the Brazilian
tropics. One study examined the tree
6th Brazilian Encontro and 8th International Conference on Tropical Bees Part II
Malcolm T. Sanford
In my first article on the sixth Brazilian
Encontro, I closed with the following statement:
“Evidence is provided that some (native bees) originated in the Cretacious period, when South America was still connected
to Africa as part of a land mass known as Gondwanaland, whereas others appear
to be the result of much more recent arrivals from
The most studied and sensational recent
Dr Marco Antonio Del Lama provided some
historical information on what researchers believe are
the major evolutionary lines of honey bees.
These insects appear to have colonized both Europe and
Introductions to the
The Africanized honey bee in
During three (3) years (1990-1993), 1738
swarms were captured in the
Although the methods were different in
comparing populations in both areas of
Dr. Robert Danka says that the shift in genetic composition reported by others should not be surprising, given the “remarkable reproductive advantage accruing to Africanized honey bee (AHB) magnified by the rather poor ability of European bees (EHB) to survive in the tropics, especially the lowlands.” High mortality of managed EHB colonies (up to 15 percent in many cases) is reported, most often linked to predation and unpredictable food shortages, common in tropical regions, but not in temperate areas. The vigorous nest defense mechanisms and high rates of absconding (migratory swarming) in AHB are thought to be effective responses to both problems.
The mechanisms that favor continuity of
the African genome in the
There was no advantage seen for AHB drones
during the queen rearing phase, but plenty of evidence suggests there was
subsequently. Virgin queens with AHB
fathers emerged sooner, developed faster and were
fiercer fighters during queen rivalry sessions.
Nest usurpation (takeover of colonies) by AHB is generally considered a given in most areas where this insect has been introduced. However, the condition of the colony (weak colonies are more susceptible) and timing are critical as AHB has both a reproductive (swarming) and absconding (migrating) season or cycle to take into consideration. The study concludes: "re-queening colonies during certain times of the year could actually increase the vulnerability to becoming African...Identifying when swarming and absconding by feral African colonies occurs (sic) in a given area and avoiding re-queening at those times could be critical to maintaining European matrilines (queens)."
Finally, there is a major controversy about the Africanization process surrounding what is called “hybrid inferiority.” The idea is that if hybrid workers are at a disadvantage, this could be a big reason that European bees decline over time. Using four genotypes (AA, AE, EE, EA, representing A and E queens mated to both kinds of drones respectively), the authors found that what they call “developmental stability” was in fact higher in pure Africans (AA) than the other genotypes, providing more evidence for this phenomenon.
Dr. Kirk Visscher
discussed the history and current status of Africanized honey bees in the
The bottom line is that the bees have
continued to spread northward in the West, and in
The invasion, nevertheless, continues and
the Africanized honey remains a threat to populations, especially in southern
Response to population increase has come
in several ways. Prevention of problems by “bee
proofing” structures, educating the populace and diluting the gene pool has
been of limited help. The first strategy
is costly and often not considered necessary by much of the general public unless a stinging
incident occurs. The last has also not
been as successful as first thought.
Increased fear of bees has cost beekeepers locations as happened in most
Interception refers to situations where
bees are collected before they move into structures. A dilemma, according to Dr. Visscher, is that initially swarms are not defensive and
can be captured and destroyed easily.
However, if one waits too long and the colony becomes established the
situation can worsen. Professional
removal services are expensive. Some
entrepreneurs have instigating trapping procedures,
however, “this works best with coordination over a reasonably large area, so it
has mostly been restricted to golf courses and other large land holdings.” Perhaps the best example of this is the
program developed in
Like so many phenomena in agriculture,
treatment should be a last resort, but often isn’t. It involves safe removal of bees from
structures and other locations that are difficult to find and access. Again, private enterprise has taken the lead,
but increased stinging incidents may bring on enough complaints in certain
areas that agencies and local governments will have to
provide these services. Dr. Visscher says that it is likely that problems with these
bees will continue to increase, especially in newly colonized areas of
concludes: “Although climatic factors are surely important, the final
distribution of Africanized bees may be determined by competition with European
honey bees as much as by climatic barriers.
The abundance of European bees, in turn is dependent on beekeeping and
on response of unmanaged honey bee populations to parasites and diseases. Africanized bees arrived in the
1. M.T. Sanford, Apis Newsletter, IFAS University of Florida , July and August 1989<http://apis.ifas.ufl.edu/apis89/apjul89.htm#1> and<http://apis.ifas.ufl.edu/apis89/apaug89.htm#1>, accessed July 19, 2004.
2. Hotel JP Home Page <http://www.hoteljp.com.br/>, accessed July 19, 2004.
3. Sixth Encontro de Abelhas Home Page <http://rge.fmrp.usp.br/abelhudo/>, accessed July 19, 2004.
4. International Bee Research Association Home Page <http://www.ibra.org.uk/>, accessed July 19, 2004.
5. For more information, e-mail <firstname.lastname@example.org>.
6. Page <http://www.apacame.org.br>, accessed July 19, 2004.
6th Brazilian Encontro and 8th International Conference on Tropical Bees Part III
Malcolm T. Sanford
In contrast to many scientific meetings
about honey bees, the sixth Brazilian Encontro also
included a symposium on honey bee products as they relate to human health. This is an area that is often ignored by
those practicing modern medicine, however, there is growing scientific evidence
that this should no longer be the case.
According to Dr. Shona Blair of the University
of Sydney, Australia’s
One factor involved in honey’s antibacterial activity is high sugar concentration, resulting in “low water activity,” according to Dr. Blair, often below that required by most bacteria. This is true of most concentrated sugar solutions, however, honey retains its properties after being diluted and has been found to be “significantly more effective than sugar solutions of similar water activity.” Another factor is that glucose oxidase, secreted from the pharyngeal glands of the honey bee, reacts with glucose to form hydrogen peroxide at concentrations high enough to inhibit bacterial growth.
Some of honey’s healing attributes go beyond high sugar content and hydrogen peroxide formation, and appear to depend on floral source, Dr. Blair writes: The best known are Leptospermum scoparium (manuka) from New Zealand and certain other Leptospermum (jelly bush) honeys from Australia. The active components of these have yet to be identified, but their effects on Escherichia coli, Staphylococcus aureus and Acinetobacter spp. are encouraging, especially given that many bacteria are already or are quickly becoming resistant to antibiotics. Honey also has therapeutic properties on human tissues, which also contributes to healing. It stimulates human cells grown in vitro (Petri dish) and activates macrophages (scavenger cells), stimulating them to release a number of cytokines, such as interleukin 1-alpha and 6.
Given all the evidence, Dr. Blair concludes: “Honey is a grossly underutilized wound dressing.” This is also true for chronic ulcers that do not respond to conventional treatment, while honey has given remarkable results under complex circumstances, even involving antibiotic-resistant organisms.
Dr. Rose A. Cooper of the
Dr. Cooper provided historical information on the curative aspects of honey and a listing of specific clinical evidence. The mindset of many doctors, and more importantly the regulators, is beginning to change with reference to honey use, she says. A honey-impregnated wound dressing was approved in March, 2004, and more products are expected to follow. Most “medical practice has adopted an evidence-based approach, and practioners will only modify procedures when provided with suitable evidence,” Dr. Cooper concludes. Fortunately, this is gradually accumulating and Dr. Cooper is confident that opinion is rapidly changing concerning the use of honey in treating wounds.
The use of propolis
has been on the increase in
The authors provide the following chronicle of events:
1973 Propolis importation to
1979 Research on propolis began at Tamagawa University
1985 Apimondia Congress, Nagoya, the beginning of widespread propolis use in Japan
1987 Japanese Propolis Conferences (JPC) begin
1991 Dr. Matsuo reports anti-tumor properties for three compounds in propolis
1997 Propolis Researcher’s Association (PRA) begins
1998 Japanese Society of Alternative Medicine started, name changed to Japanese Society of Complementary Alternative Medicine (JSCAM) in 2000.
Since 1997, the PRA has had a litany of
The PRA was established precisely because of the confusion, the authors say. It has encouraged research on one hand while on the other it has provided education for both consumers and health practitioners. The bottom line is that both should always consider the kind of propolis being used. Papers presented at the PRA run the gamut from basic properties to manufactured products, including specifically those concentrating on:
properties of propolis
Active ingredients found in propolis
In vivo (live) and in vitro (Petri dish) activity of propolis
Clinical trials and safety tests
Food engineering aspects
Standards and grading of propolis products
Scientific papers have appeared in a variety of scientific journals, including Biological Pharmaceuticals Bulletin (propolis effect on human cells lines and leukemia), Food Chemistry (antioxidant properties of propolis), Org. of Biological Chemistry, and Cancer Letters.
The complexity of Brazilian propolis is evident when considering a paper by Dr. Yong
Park, from the
As expected, Dr. Park found a great variety of activity in the propolis samples. He meticulously recorded his results in various charts and tables, and concludes that all this information punctuates the complexity of studying propolis and its biological activity.
Dr. Walter Ferro Morales from
Although there are standards for both propolis and honey in
Dr. G.J. Padovan
and colleagues compared the quality of honey being marketed in the
Several other areas of interest were explored through symposia at the Encontro. These included sustainable development in beekeeping, sensory perception and learning in honey bees, stingless bee biology and advances in genomic and molecular biology. Several papers on sustainability emphasized the wide range of possibilities the keeping of both Apis and non-Apis bees has in the developing world.
Dr. Wyatt Mangum reported a number of innovations he has found around the world. For example, one Bolivian beekeeper rents out his expertise in managing colonies of highly defensive Africanized bees owned by others. He also described innovations in keeping non-Apis bees by beekeepers who have designed nesting materials and other technologies to harvest colonies from the wild. Unfortunately, all these activities, Dr. Mangum concluded, are threatened by the pervasive worldwide movement of both honey bees and bee pests out of their native ranges, including diseases like American foulbrood (Paenibacillus larvae larvae), Tropilaelaps clarae (an Asian parasitic mite), Apis mellifera scutellata (overly defensive Africanized bees), Apis mellifera capensis (honey bees producing “false queens”), and Aethina tumida (small hive beetle).
As would be expected, a variety of papers were also presented in the bee pathology area. Several of the most relevant included original research on Varroa mite infestation. One Venezuelan study revealed that “survivor” colonies of Africanized honey bees that had never been treated had a greater number of non-reproducing female mites than would be expected. A bioassay has been developed to reveal how Varroa mites are attracted to comb and brood. It was concluded: “With this system, the mites made choices similar to those they make in honey bee colonies, such as preferring old brood comb wax to newly constructed comb and drone brood food over royal jelly.” The former conclusion is being examined as a possible natural control of Varroa by incorporating new and renovating aged comb extracts to wax foundation. Another study concluded that Varroa infestation in worker brood decreased as the amount of brood in a colony increased, however, the relative infestation rate in drone brood remained relatively constant. An apparatus was described to film activities inside a colony, producing the first “real time” images of interactions between worker bees and Varroa mites.
No conference on bees is complete these
days without some treatment of diseases.
American foulbrood is so far not recorded in
As I said in the initial article on this series, the magnitude of the published document produced containing the proceedings of the 6th Brazilian Encontro and 8th International Conference on Tropical Bees defies giving it justice in a few short articles. It is my fervent hope, however, that the readership will get a flavor of the meeting from these three summary articles. It might even be that some are stimulated enough to buy the proceedings on CD ROM from the International Bee Research Association <http://www.ibra.org>. The information certainly deserves wider dissemination in the apicultural community.
Thanks to Dr. Lionel Gonçalves for encouraging me to write this series and providing me with a copy of the proceedings. I would like to specifically acknowledge the help of Dr. David De Jong, who conscientiously read and edited each article before it went to press.