Macropod hybrids

Macropod hybrids are hybrids of animals within the family Macropodidae. Several macropod hybrids have been experimentally bred, including:
* Eastern Wallaroo ("Macropus robustus") X Red Kangaroo ("Macropus rufus"). Result: "infertile female with one ovary"
* Swamp Wallaby ("Wallabia bicolor") X Red-necked Wallaby ("Macropus rufogriseus"). Result: "sterile male"
* Agile Wallaby ("Macropus agilis") X Red-necked Wallaby ("Macropus rufogriseus"). Result: "sterile male"
* Tammar Wallaby ("Macropus eugenii") X Black-striped Wallaby ("Macropus dorsalis"). Result: "sterile male"All of the above hybrids showed a mix of traits from both parents and all were found to be sterile (the female may have been so poorly fertile as to be considered sterile). Although the males had testes, they did not produce sperm and some were found to have Y-chromosome abnormalities.cite web | url = http://www.messybeast.com/genetics/hybrid-marsupials.htm | title = Hybrid Marsupials]

*The Eastern and Western Grey Kangaroos have bred in enclosures, producing sterile male young and fertile female young, who readily bred back with male Western Greys.

Hybrids have been bred from the following combinations:

* Red Kangaroo (Macropus rufus)X Great Grey Kangaroo (Macropus giganteus)
* Red kangaroo (male) X Wallaby (female); assumed to be sterile.
* Garden Island Tammar (Scrub Wallaby, "Macropus eugenii") X Kangaroo Island Tammar
* Tammar Wallaby X Parma ("Macropus parma") (by in-vitro fertilization)

Hybrids have been attempted between the Tammar Wallaby and the wallaby-like Pademelon (Thylogale sp)

Some hybrids between similar species have been achieved by housing males of one species and females of the other together to limit the choice of mate. To create a "natural" macropod hybrid, young animals of one species have been transferred to the pouch of another so as to imprint into them the other species. In-vitro fertilization has also been used and the fertilized egg implanted into a female of either species.

References

* Poole, WE "Reproduction in the Two Species of Grey Kangaroos, Macropus Giganteus Shaw and M. Fuliginosus (Desmarest). Ii. Gestation, Parturition and Pouch Life." Australian Journal of Zoology 23(3) 333 - 353 (1975)
* MJ Smith, DL Hayman and RM Hope, "Observations on the chromosomes and reproductive systems of four macropodine interspecific hybrids" Australian Journal of Zoology 27(6) 959 - 972 (1979)