Beefalo, also referred to as cattalo or the American hybrid, are a fertile hybrid offspring of domestic cattle (Bos taurus), usually a male in managed breeding programs, and the American bison (Bison bison), usually a female in managed breeding programs.   The breed was created to combine the characteristics of both animals for beef production.
Beefalo are primarily cattle in genetics and appearance, with the breed association defining a full Beefalo as one with three-eighths (37.5%) bison genetics, while animals with higher percentages of bison genetics are called "bison hybrids".
The first deliberate attempts to cross breed bison with cattle was made by Colonel Samuel Bedson, warden of Stoney Mountain Penitentiary, Winnipeg, in 1880. Bedson bought eight bison from a captive herd of James McKay and inter-bred them with Durham cattle. The hybrids raised by Bedson were described by naturalist Ernest Thompson Seton: 
The hybrid animal is [claimed] to be a great improvement on both of its progenitors, as it is more docile and a better milker than the Buffalo, but retains its hardihood, while the robe is finer, darker and more even, and the general shape of the animal is improved by the reduction of the hump and increased proportion of the hind-quarters.
After seeing thousands of cattle die in a Kansas blizzard in 1886, Charles "Buffalo" Jones, a co-founder of Garden City, Kansas, also worked to cross bison and cattle at a ranch near the future Grand Canyon National Park, with the hope the animals could survive the harsh winters.  He called the result "cattalo" in 1888.  Mossom Martin Boyd of Bobcaygeon, Ontario first started the practice in Canada, publishing about some of his outcomes in the Journal of Heredity.  After his death in 1914, the Canadian government continued experiments in crossbreeding up to 1964, with little success. For example, in 1936 the Canadian government had successfully cross-bred only 30 cattalos.  Lawrence Boyd continues the crossbreeding work of his grandfather on a farm in Alberta.[ citation needed]
It was found early on that crossing a male bison with a domestic cow would produce few offspring, but that crossing a domestic bull with a bison cow apparently solved the problem. The female offspring proved fertile, but rarely so for the males. Although the cattalo performed well, the mating problems meant the breeder had to maintain a herd of wild and difficult-to-handle bison cows.[ citation needed]
In 1965, Jim Burnett of Montana produced a hybrid bull that was fertile.[ citation needed]  Soon after, Cory Skowronek of California formed the World Beefalo Association and began marketing the hybrids as a new breed. The new name, Beefalo, was meant to separate this hybrid from the problems associated with the old cattalo hybrids. The breed was eventually set at being genetically at least five-eighths Bos taurus and at most three-eighths Bison bison.
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A United States Department of Agriculture study[ citation needed] found Beefalo meat, like bison meat, to be lower in fat and cholesterol than standard beef cattle. The American Beefalo Association states that Beefalo are better able to tolerate cold and need less assistance calving than cattle, while retaining domestic cattle's docile nature and fast growth rate. They damage rangeland less than cattle.  They also state that Beefalo meat contains 4 to 6% more protein and is more tender, flavorful, and nutritious than a standard steer.  Beefalo has significantly less calories, fat, and cholesterol, than beef cattle, chicken, and cod. 
The American Beefalo Association states that the "crossbreeds are hardier, are more economical (and less care-intensive) to nurture, and produce meat that's superior to that of the common cow." 
In 1983, the three main Beefalo registration groups reorganized under the American Beefalo World Registry. Until November 2008, there were two Beefalo associations, the American Beefalo World Registry  and American Beefalo International. These organizations jointly formed the American Beefalo Association, Inc., which currently operates as the registering body for Beefalo in the United States. 
Most current bison herds are genetically polluted or partly crossbred with cattle.     There are only four genetically unmixed American bison herds left, and only two that are also free of brucellosis: the Wind Cave bison herd that roams Wind Cave National Park, South Dakota; and the Henry Mountains herd in the Henry Mountains of Utah.  A herd on Catalina Island, California is not genetically pure or self-sustaining.
Dr. Dirk Van Vuren, formerly of the University of Kansas, however, points out that "The bison today that carry cattle DNA look exactly like bison, function exactly like bison and in fact are bison. For conservation groups, the interest is that they are not totally pure." 
In some U.S. states, cattalo are regulated as "exotic animals", along with pure bison and deer. However, in most states, bison and hybrids which are raised solely for livestock (meat and sale) purposes similar to cattle, are considered domestic animals like cattle, and do not require special permits.
- American cattle
- Bovid hybrid
- Haldane's rule
- Wind Cave bison herd
- Antelope Island bison herd
- Porter, Valerie (2008). The Field Guide to Cattle. Voyageur Press. p. 70. ISBN 978-0-7603-3192-7. Retrieved 14 May 2015.
- Drew, K. R.; Baskin, L. M. (1989). Wildlife Production Systems: Economic Utilisation of Wild Ungulates. CUP Archive. p. 354. ISBN 978-0-521-34099-1. Retrieved 14 May 2015.
- Dafoe, John W. (April 1889). "Domestication of the Buffalo". Popular Science Monthly. 34. Retrieved 21 March 2018.
- Brower, Jennifer (2008). Lost Tracks: National Buffalo Park, 1909-1939. Athabasca University Press. pp. 132–133. ISBN 978-1-897425-10-7. Retrieved 14 May 2015.
- "Charles Jesse "Buffalo" Jones". Kshs.org. Retrieved 2009-10-02.
- "The Story of Cattalo". canadiangeographic.ca. May 2011. Archived from the original on 2005-09-01.
- Boyd, M. M. (1914). "Crossing bison and cattle". J Hered (5: 189-197.).
- Magazines, Hearst (December 1934). "Cattle Developed for North are Part Buffalo". Popular Mechanics. Hearst Magazines. p. 863. ISSN 0032-4558. Retrieved 14 May 2015.
- Bovid Hybrid. Books LLC. 2010. ISBN 9781158607723.
- Beefalo Facts
- Nutrition and Taste
- "ABWR". ABWR. Archived from the original on 12 October 2009. Retrieved 2009-10-02.
- "American Beefalo Association". Retrieved 14 May 2015.
- "Strands of undesirable DNA roam with Buffalo, By Jim Robbins, 9th January 2007, The New York Times". Wildcattleconservation.org. Retrieved 2009-10-02.
- Polzhiehn, R.O.; C. Strobeck; J. Sheraton & R. Beech (1995). "Bovine mtDNA Discovered in North American Bison Populations". Conservation Biology. 9 (6): 1638–43. doi: 10.1046/j.1523-1739.1995.09061638.x. JSTOR 2387208.
- "Halbert, N.D., Ward, T.J., Schnabel, R.D., Taylor, J.F and Derr, J.N. (2005) Conservation genomics: disequilibrium mapping of domestic cattle chromosomal segments in North American bison populations. Molecular Ecology (2005) 14, 2343–2362" (PDF). Animalgenomics.missouri.edu. 2009-02-12. Archived from the original (PDF) on 2006-04-22. Retrieved 2009-10-02.
- "Halbert, Natalie Dierschke (2003) The utilization of genetic markers to resolve modern management issues in historic bison populations: implications for species conservation Ph. D. Dissertation, Texas A&M University, December 2003" (PDF). Retrieved 2009-10-02.
- "Genetically Pure Bison Found in Utah". UPR Utah Public Ratio. 2015-12-16. Retrieved 2015-12-24.
- Catherine Brahic (October 15, 2008). "American icons aren't the animals they used to be". New Scientist. Retrieved 2015-01-07.
- "Code of Federal Regulations (9CFR352.1) rev 2004. — "Catalo or Cattalo means any hybrid animal with American bison appearance resulting from direct crossbreeding of American bison and cattle."". Access.gpo.gov. Archived from the original on August 26, 2009. Retrieved 2009-10-02.