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History of the Syrian Hamster 
zondag, 28 augustus, 2011, 8:56 am - Syrische hamsters
door Martin Braak
Chris Henwoon heeft op Rodent Genetics Group, een groep op Facebook, een artikel over de geschiedenis van de Syrische hamster geplaatst. Hieronder heb ik een kopie van dit artikel geplaatst. Dit omdat het erg interessant is.

History of the Syrian Hamster
The Discovery of the Syrian (Golden) Hamster, Mesocricetus Auratus
by Chris Henwood

We all think we know the Syrian or Golden Hamster, and its history, but do we? We have all heard the story of how in 1930 a mother and babies were dug from the Syrian Des...ert and these are the founders of all the hamsters alive today, but is this the real story? I research this subject quite a few years ago and came across some surprising details. I looked very closely at the myths that surround the "discovery" of the Syrian Hamster in 1930. But even then I miss quite a few details. Even more details have come to light over recent years and I have therefore added these details to this history.

The earliest known description of the Golden Hamster, as it was then always called, was published in 1797 (yes as long ago as that) in the Natural History of Aleppo by Alexander Russell, with additional notes by his younger brother Patrick. I think that it is perhaps important to know a little about Alexander. He was a physician practising in the Aleppo area of Syria from 1740-1750, where it appears he became one of the leading experts on the plague that was sweeping the area. During these ten years he kept very detailed records of the fauna, flora, climate and culture of the region. In fact he appears to have taken notes on every detail of the area and the people that lived there, and published the first edition of the Natural History of Aleppo in 1756. Patrick Russell lived in Aleppo from 1750-1781 and published the second edition well after the death of Alexander. The Hamster was not mentioned in the first edition, but is in the second. So perhaps Patrick discovered the species, but nothing is certain; it may also have been contained in unpublished papers of Alexander and not discovered until after his death when Patrick decided to revamp the text. The passage on the hamster from this book which is now, perhaps naturally, out of print, reads "... The hamster is less common than the Field Mouse. I once found upon dissecting one of them, the pouch on each side stuffed with young French beans, arranged lengthways so exactly, and close to each other, that it appeared strange by what mechanism it had been effected; for the membrane which forms the pouch, though muscular, is thin, and the most expert fingers could not have packed the beans in more regular order. When they were laid loosely on the table, they formed a heap three times the bulk of the animals’ body.

To me the most surprising thing is that Russell (whichever) did not claim to have discovered a new species, but appears to have mistakenly accepted the Syrian was the same species as the Common European Hamster. Therefore the species wasn't named either by or after Russell. Instead the Syrian or Golden Hamster was named by George Robert Waterhouse, who presented it as a new species in 1839.

George Robert Waterhouse was, at the age of 29, Curator of the London Zoological Society. He presented the "new" species at a meeting of the Society on the 9th April 1839. This presentation was based on a single rather elderly female specimen received from Aleppo, Syria. Isn't it strange how Aleppo appears at every stage in the history of this species? His description was published in the Society's proceedings of 1840 thus: "... This species is less than the Common Hamster (Cricetus Vulgaris) (Please note that this has since been changed to Cricetus Cricetus) and is remarkable for its deep golden yellow colouring. The fur is moderately long and very soft and has a silk-like gloss; the deep yellow colouring extends over the upper parts and sides of the head and body and also over the outer sides of the limbs; on the back the hairs are brownish at the tips hence in this part the fur assumes a deeper hue than on the sides of the body; the sides of the throat and upper pans of the body are white, but faintly tinted with yellow; on the back and sides of the body, all hairs are of a deep grey or lead colour at the base. The feet and tail are white. The ears are of moderate size, furnished externally with whitish hairs. The moustaches consist of black and white hairs intermixed ..." The collector and donor of the specimen was either unknown or at the very least unacknowledged, but following the description this hamster, remember an elderly female so perhaps not in good health when captured, became the "type" specimen for the new species Cricetus Auratus; Waterhouse (the genus name Mesocricetus was a later modification). I recently found this old lady still at the Natural History Museum in London. She is a rather sorry sight but is quite interesting. She is actually named: - Item BM(NH) 1855.12.24.120. (Not a very nice name for such a wonderful old girl).

So now if you take the old story as the truth then little was heard of the Golden Hamster for almost exactly 100 years. Wrong! In fact a group of unknown number was brought from Syria to the UK by James Skeene. He had been British Consul to Syria and on his retirement in 1880 returned to Britain. I can sadly find no reference that he wrote anything about the species in general or his animals in particular, and if anyone can help with this area I would be very grateful. It does however appear that they bred in this country at least until 1910 when the last individuals appear to have either died or been destroyed (perhaps on the death of Skeene?). In addition to this a single female (dead) was sent to the Berlin Museum in 1902, this female appears to have been captured near Aleppo in the same year by a person called Zumoffen.

Then again nothing is heard of the species and there appears to be of little interest in it until the late 1920s. At this time Saul Alder a parasitologist at the Hebrew University of Jerusalem was conducting research on the prevalent disease, Leishmaniasis, for which the "Chinese" Hamster had been shown to be an excellent animal model. However, Alder had been unable to breed Chinese Hamsters successfully and found it totally unacceptable to keep relying on shipments from China. He therefore wanted to obtain a species of hamster that was endemic to the Middle East. It appears that he knew of the Syrian Hamster from reading the description by Waterhouse, but some authorities propose (and I think I would go along with this) that he was actually more interested in the Grey or Migratory Hamster (Cricetulus Migratorius) which was and still is quite widespread in Asia Minor. Whichever he was looking for, he asked a colleague from the Zoology Department to help him obtain some endemic hamsters. Thus it appears that the real reason we have the Syrian today is due to the fact that the Chinese Hamsters were unwilling to have anything to do with sex.

Sorry ... back to the story ... well the zoologist in question was one Israel Aharoni - quite a colourful character from what I can gather. He was born in Widzi on the Russian/Polish border and educated in Prague. He is known as the first Hebrew zoologist because he rediscovered or at least assigned Hebrew names to the animals of the Holy Land. At the time of his early life and expeditions in Jerusalem the region was still under the strict rule of the Turks. Aharoni, a Jew, in a Moslem world was only able to travel freely under the protection of the local Turkish Sultan and he received this because he obtained specimens for the Sultan's butterfly collection. On these collecting trips he appears to have collected just about every animal he came across, always assisted by local guides; the initial preparation of the specimens was done in the field and then they were sent to Berlin. However, many of his specimens are still available for you to study today if you care to visit the Russian Compound of the Hebrew University in Jerusalem.

It was on one such expedition as this in 1930 that Aharoni on Saul Alder's request looked for hamsters. An account of this was published in Aharoni’s memoirs in 1942. Although there may be some question as to whether or not Alder knew of the Syrian Hamster, Aharoni certainly did and he knew that it was this species he would look for. It appears that on his arrival in the Aleppo region, he instructed his local Syrian guide Georgius Khalil Tah'an, to go to a certain farm and entreat the local Sheikh (Sheikh El-Beled) to provide information on the location of the hamsters in the area. On 12th April 1930, the Sheikh called a meeting and it was decided by the village to hunt out this creature in the best fields that had a colony. The Sheikh hired a few locals as labourers and they dug in many areas destroying a good proportion of the wheat field. After quite a few hours of hard work they succeeded in raising from the depth of eight feet a complete nest, nicely populated by a female and her eleven young. Thinking that the mother would care for her infants and feed them well with no problems, the whole family was placed in a colony box. I think that what happened next is so important that it should be left to Aharoni's own words: '... I saw the hamster harden her heart and sever with ugly cruelty the head of the pup that approached her most closely (each of the young measuring about 2.5 cms) natural mother love led her to kill her dear child. 'It is better that my infant die than that it be the object of an experiment performed on it by a member of the accursed human race'. When Georgius saw this act of savagery,, he quickly removed the mother hamster (for she would surely kill them all) and put her in a bottle of cyanide to kill her ..." So, simply because this, the first live captured wild female hamster was an anti-vivisectionist and didn't realise how much her offspring would soon come to mean to so many people, she died. Aharoni however was left with ten babies to raise by hand. There is no record of the approximate age of the litter, but their eyes were still closed when captured. Aharoni and his wife did succeed as foster parents and the litter survived. After an escape and recapture of nine of them they were given to Hein Ben-Menachen. the founder and head of the Hebrew University Animal Facilities on Mt. Scopas.

Ben-Menachen placed the hamsters in a cage with a wooden floor. The next morning five had escaped having chewed their way through the bottom of the cage. Ben-Menachen was very upset, particularly when Aharoni pointed out how difficult it was to capture these creatures. None of the five escapees were recovered alive. According to Aharoni the remaining four consisted of three males and a single female. However, the statement is contradicted by S Alder in 1948; in which he indicated that one male and three females survived the escape attempt and one female was later killed by the male. Israel Aharoni was rather sceptical that the remaining animals would breed, but Hein Ben-Menachem had other ideas. He filled a large wire mesh cage with tightly packed hay, leaving only 5 cm brightly illuminated space on the top. Into this space he placed his female. Seeking darkness, the female began to burrow into the hay. A day or so later the male was placed into the cage. It proceeded to chase the female and finally caught up with her. By then both were tired and the male was presumably quite aroused. Their position in the burrow was more favourable to mating than to slaughter, and they mated. The first hamster colony was prolific and numbered 150 within the first year, although again various authorities have different figures: including strangely 365 for the first year.

The first laboratory-bred hamsters were given to Alder who published a report on the first research using Syrian Hamsters a short time later. Realising the fragility of a single colony Alder distributed stock to various other laboratories. The Syrian Hamsters arrived in England in 1931 and were literally smuggled into the country in Alder's coat pockets: why, I’m afraid, I don't know. These were given to E Hindle of the Zoological Society of London.

The Zoological Society of London does not appear to have any record of how the animals received by them appeared a few years later on the pet market. Recently I came across a name that had been mentioned a few times but I could never really track down what his link with the Syrian or Golden hamster in the UK was.

Leonard George Goodwin was a British protozoologist. He was noted for his work on testing the effectiveness of chemical compounds in treating tropical diseases. Before during and after the Second World War, he worked at the Wellcome Bureau of Scientific Research. While working there he attempted to find a way to prevent British troops fighting in Europe from being infected with leishmaniasis. The standard way of calculating the dosage of this drug was to give a person, was to use the “chemotherapeutic index”, this was an amount between the minimum dosage to cure the infection and the point at which the drug would kill the patient. Leonard Goodwin’s attempt at refining the index by testing the drug on European Hamsters failed as they proved resistant to Leishmaniasis; instead he obtained stocks of the Syrian Hamster, supposedly from Jerusalem via the Zoological Society of London to test the drugs on. The research quickly showed that the Pentostam was the least toxic and most effective drug available to treat the disease and was issued to the troops within a year.

Goodwin later claimed in one of his papers that the Syrian Hamsters bred as pets in the UK were for the most part descended from the colony he had bred and also credited himself with the introduction of the animal to the UK. Sadly Leonard Goodwin died in November 2008 and I can find no additional details relating to his work with the Syrian Hamster.

So .......back to the Middle East. Although not mentioned by Aharoni in any papers, he apparently captured more individuals than just the mother and her litter, as three adult female specimens captured on April 27th & 29th 1930, and attributed to him. are in the collection of the Berlin Museum and can still be seen there. Although the paper work there states that the animals were obtained in 1932 and not 1930. There is general agreement that hamsters were first imported into the USA in the summer of 1938, although the exact nature of the importation is confused as is the importation of stock to mainland Europe.

There is a mention in papers that in 1962 3 individuals were caught near Aleppo and sent to the United States via Turkey. I can find no further details on these animals but it has been suggested that they were actually from Turkey and not Aleppo.

The next recorded capture of wild Syrian Hamsters that I can trace was in May and June 1971, when American Michael R Murphy obtained thirteen animals at Aleppo. Twelve (four males and eight females) were taken back to the USA. Murphy records that after only three days of handling, the wild caught hamsters were tame and gentle. All animals mated within four weeks of capture and all eight females produced litters. The average litter size was eleven and every baby was raised to weaning. All attempts at trying to track down this colony and the outcome of the colony once they arrived in the USA have failed. If any person has any information on these it would be most gratefully received. In 1978 Bill Duncan of SW Medical School Dallas, Texas, USA made a third capture in the same area and returned to the USA with two females. Again I can trace no information on this group.

In 1980 a Rodent Control Officer, while working at the Field Centre for the International Centre for Agricultural Research in the Dry Areas, captured two animals both of which had unfortunately eaten rat bait being tested and died soon after. In November 1982 the same officer captured, at the same site, a further pair: sadly the male died within a short period, and although the female reached quarantine in England safely, no attempt was made to breed her. With the help of the Zoological Society of London, and Clinton Keeling, she arrived at my home in June 1983. She was an extremely tame individual who was up and about at all times of the day and made great friends with myself. Sadly, although every attempt was made to breed from her, all failed - I assume due to her age; she eventually died in January 1985 at a ripe old age. In 1986 three males were captured near Aleppo and taken to Tubingen in Germany, as with the London female no reproduction took place.

In 1999 The Halle University under the leadership of Prof Rolf Gatterman conducted studies of the Syrian Hamster. Four individuals were obtained and used for taxonomical studies. In early spring an additional pair were again caught for the same reasons. In March a further 13 individual hamsters seven males and six females were caught alive at two locations near Albel/ Shaykh-Rieh and Amaz, about 50 km north east and 20 km south west of the city of Aleppo. One of the females was pregnant and produced a litter of six. These animals were taken to Halle University in Germany forming a new breeding line. Although I was in regular contact with Prof Gatterman in the years soon after their arrival he sadly died of cancer in 2006. I have since been unable to form any type of contact with the present authorities at Halle., although attempts are continuing to see if animals form this line could be released to certain individuals with the Hamster keeping community.

@copyright Chris Henwood 2011
'Eén gen verantwoordelijk voor drie kankersoorten'  
zondag, 28 augustus, 2011, 8:41 am - Andere zaken
door Martin Braak
Op het forum hebben we wel eens discussies hoe afwijkingen vererven en sommigen denken dat het polynogwat vereft wat betekent dat het meerdere genen nodig heeft om te uiten. De kans dat meerdere genene bij elkaar komen, heb ik al vaker op mijn blog geschreven, is zeer klein. Doe maar eens een test door een champagne, vier genen, te kruisen met een wildkleur en dan onderling. Dat je champagne terug krijgt... kans is 1 op 64.

Onderstaande post ik omdat ik het intressant vind en vast wil leggen. Dit is afkomstig van Nu.nl:

Amerikaanse onderzoekers linken één defecte gen aan tenminste drie verschillende kankersoorten.

In het onderzoek, gepubliceerd in Science, ontdekten de wetenschappers dat een vijfde van alle huidkankergevallen, Ewing's sarcomen (botkanker) en glioblastomen (hersenkanker) een defect in het gen STAG2 had.

Dit gen controleert normaliter de verdeling van al het genetisch materiaal tussen de cellen.

Defect

Gewoonlijk heeft een mens 46 chromosomen (23 paar); de dragers van erfelijk materiaal (DNA). Bij de celdeling verdubbelt iedere chromosoom zich. Dan zijn er dus 23 paren in allebei de cellen. Soms gaat dit fout en zijn er te veel of juist te weinig chromosomen, dit komt vaak voor bij kankercellen.

Naar nu lijkt, zorgt een defect gen STAG2 ervoor dat een normale cel een kankercel wordt door fouten te maken bij de verdeling van de chromosomen.

De onderzoekers van Georgetown University in Washington vonden defecte STAG2 genen bij 21 procent van de mensen met Ewing's sarcomen. Het defect werd ook aangetroffen bij 19 procent van de glioblastomen en bij 19 procent van de melanomen (huidkanker).

Geneesmiddel

Professor Todd Waldman: "Bij de kankersoorten die we bestudeerden, lijken mutaties in gen STAG2 de eerste stap naar de vorming van kankercellen. We gaan nu kijken of dit gen ook gemuteerd is bij mensen met borstkanker, darmkanker, longkanker en andere veel voorkomende kankersoorten. Wellicht kan er dan uiteindelijk een geneesmiddel worden ontwikkeld dat alleen cellen met een defect STAG2 doodt. Dan zouden sommige kankersoorten voorkomen kunnen worden."

Nu.nl
http://www.nu.nl/gezondheid/2593659/een ... orten.html
Stress kan DNA beschadigen 
vrijdag, 26 augustus, 2011, 7:11 pm
door Martin Braak
Amerikaanse wetenschappers hebben een verband gevonden tussen stress en beschadigd DNA.

De adrenaline die vrijkomt door stress kan bij muizen biologische processen in gang zetten die leiden tot blijvende schade aan het DNA.

Deze reactie zou ook kunnen verklaren waarom een stressvol bestaan lichamelijke klachten kan veroorzaken bij mensen. Dat schrijven onderzoekers van Duke University in het wetenschappelijk tijdschrift Nature.

Grijs haar

“De ontdekking biedt ons een plausibele verklaring voor het ontstaan van stoornissen in het menselijk lichaam als gevolg van stress”, verklaart hoofdonderzoeker Robert Lefkowitz op nieuwssite Physorg.com.

"We hebben het dan over de meest uiteenlopende aandoeningen: van grijs haar tot kwaadaardige tumoren", aldus Lefkowitz.

Muizen

De wetenschappers kwamen tot hun bevindingen door muizen met behulp van een infuus bloot te stellen aan grote hoeveelheden van een samengestelde stof die vergelijkbaar is met adrenaline.

Uit het onderzoek bleek dat de stof biologische reacties ontketenende die uiteindelijk leidden tot een opeenstapeling van beschadigingen aan de chromosomen van de dieren.

Eiwit

“Daarmee hebben we het bestaan van een specifiek mechanisme aangetoond dat doormiddel van verhoogde adrenaline - een kenmerk van chronische stress - beschadigingen aan het DNA veroorzaakt”, aldus Lefkowitz.

De beschadigingen kwamen volgens de wetenschappers tot stand doordat er in het lichaam van de muizen minder van het eiwit P53 werd aangemaakt als gevolg van het verhoogde adrenaline-niveau.

Het eiwit P53 komt ook voor bij mensen en wordt ook wel de ‘bewaker van het genoom‘ genoemd, omdat de stof de vorming van tumoren onderdrukt.

Van Nu.nl
http://www.nu.nl/wetenschap/2595173/str ... digen.html

Zou dit een reden zijn dat veel mutaties bij grotere fokkers ontstaan?
Drie weekjes oud en boven in de kooi hangend 
woensdag, 24 augustus, 2011, 7:50 pm - Russische
door Martin Braak
In de woonkamer heb ik een paar kooien staan en één daarvan zit een koppel Russische dwerghamsters. Ze hebben al drie nestjes gehad. Het vierde nestje wederom zo schattig, maar wat doen ze nu! In de avond klimmen ze helemaal naar boven.

Foto behorend bij blog

Natuurlijk heb ik eerder jonge rusjes zien klimmen, maar deze zijn net drie weken oud. Het typische is, voorgaande nesten deden dat niet. Wat is het verschil?
Speciaal voer voor een Korenwolf 
vrijdag, 19 augustus, 2011, 5:37 pm - Andere zaken
door Martin Braak
Gisteren kwam ik in een mooie dierenwinkel in Nijkerk, namelijk Dierenspeciaalzaak De Oostermolen. Een prachtige winkel waar ze ook baby papagaaien hadden. Daar zag ik iets in de schappen liggen... Ik moest er ff om lachen!

Foto behorend bij blog

Voer voor o.a. een Korenwolf!! Want de hamster die op deze verpakking staat is een Korenwolf die niet in Nederland gehouden mag worden.

Waarschijnlijk willen ze de naam afbeelden, namelijk nature voor hamster en rat voor sience. Maar dat is puur een gok van me. De normale mens zal denken dat het afbeeldingen zijn waarvoor voer geschikt voor is.