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A rat, a kangaroo or a rabbit?

Brush-tailed bettong (Bettongia penicillata), is a marsupial which typical characteristic is jumping (similar to kangaroo). Its fur is grey brown, lighter on the belly. Typical is also prolonged nasal part and short round ears. Front legs are much shorter than hind legs. Average body length including head is 30 – 38 cm, weight is 1300 g. Tail is long, averaging 31 cm, sparsely furred. It is used as steering wheel when jumping but the most interesting part is that it is prehensile – bettong is able to use it as a fifth leg and hold and carry things with it. This ability is used mostly by carrying nesting material (leaves, grass) to nesting place (on the ground).
Brush-tailed bettong lives in southwest Australia. In the wild this animal does not drink water and does not eat any green plants. Its menu comprises mostly of succulent underground fungi that grow on the roots of eucalyptus and other tree species. Its foregut is noticeably developed and adapted to digesting fungi. Passing through its digestive tract, fungi spores are activated and germinate directly at the site of defecation. Intestinal flora and fauna help to ensure the presence of basic amino acids which are missing in their diet but are essential for the correct functioning of the organism. Bettongs enrich their menu by eating plant bulbs, gum of the Hakea bush species and insects. They dig their food from the underground with front paws.
Bettongs are nocturnal solitary animals. There is no visible sexual dimorphism; males and females meet mostly during the breeding season. Males in their territory monitor females’ pouch and uro-genital area – they need to find out whether female is ready to mate. Males show aggressive behaviour towards each other and kick one another with their hind legs. Non-estrous females are aggressive towards males which bother them by investigating their pouch. Mating takes place during night hours and lasts only a few seconds but is repeated several times. Females mate with several males. After short, approximately three week long gravidity, one offspring is born that weighs up to 1 gram. Immediately after the birth, the young must climb into its mother’s pouch and attaches itself to one of the four teats. On the same night, the female comes into oestrous followed by mating. Therefore the mother bettong can have three offspring of different ages: the oldest which left the pouch and only sticks its head into the pouch to suck on milk; younger offspring which is in the pouch attached to the teat; and the youngest one – an embryo in the uterus. The pouch contracts after the oldest offspring leaves it which is protective adaptive function for the new born offspring. Mother’s milk constantly changes its composition from diluted milk low in proteins and lipids and high on carbohydrates to more concentrated milk high in lipids but low in carbohydrates. The development in the pouch lasts approximately 100 days.
Bettongs give out only few sounds. The female communicates with her young in her pouch with clucking sounds. Anxious animals make a vocalization with an explosive expelling of air. Their life span is between 4 - 6 years, their predators include snakes and birds of prey.
The Red List of Threatened Species IUCN lists the bettong as critically endangered species. Population numbers in the wild decreases fast due to habitat destruction (fires, agriculture) and competition with domestic and non-native species for space and food. Bettong also belongs to the European Endangered Species Programme (EEP) which was for given species established in 1994.
Our Zoo is the first and only one in Slovakia that breeds this small and very interesting animal. Two females were transported from Prague Zoo in 2005; one male was brought on June 25^th 2009 from Duisburg Zoo. It is a great achievement and our pleasure to announce the birth of historically first bettong young in our Zoo which was born on November 10^th 2009 and left its mother’s pouch on February 18^th 2010.