The Bison Advantage

The Bison Advantage (from 2007 issue of Bison World)

By Dr. Dave Hunter, DVM

Author’s Note (2018): Looking back to look forward and redefining the Bison Advantage article has been on my mind. This advantage and its principals are now well described by the NBA through the Bison Producer’s Handbook.  Bison producers are now onboard and appreciate and utilize this concept.  The beauty is that, over the years since this article was in the Bison World and Smoke Signals magazines, understanding the Bison Advantage has allowed up to “tweak” what we all know about bison to our advantage.  We are now starting to investigate and study the species in ways that benefit the bison and our ability to humanely and economically manage them.

This term has been tossed around for many years by some producers and now has been incorporated into scientific articles in many journals.  I did not invent the moniker, but now use the “Bison Advantage” to my advantage.

What does this mean for those of us in bison production? I think it could relate to longer vacations from our business of raising bison.  Heaven knows, we don’t have enough vacation time and what we have we rarely use.  WE are married to our families, properties and to our “magnificent” production animals – bison.  We have disagreements with our families, troubles with crops and grass due to weather (global climate change) and we can use a respite form the added stress from being married to our bison day in and day out.

Let’s go back a few years, i.e. the Pliocene era, a period from 5.332 to 1.8 million years before present.  Two to three species of bison were lost during that timeframe but the smallest, and probably fittest, of bison species remained.  After this last ice age, North America grew to have the greatest diversity of wild mega-fauna the world has ever known.  Condors with 15 foot wingspans, ground sloths as big as hippos, three species of elephants, giant armadillos, three species of cheetahs, five other “big” cats, long-legged antelope-like pigs, camels, llamas, deer, horses, several species of antelope: it was indeed a “Super Serengeti.” What happened? Historic records indicate that 11,000 years ago, the Paleo-Indicans crossed the land bridge and colonized North America.  Simultaneously, or because of this crossing, 70+ species, or around 95% of the megafauna, disappeared.  Speculation was that the North American species had not evolved with humans and were easy prey for spears, arrows and intelligent human as predators. We are very fortunate that bison escaped these pressures, possibly due to sheer numbers and their gregarious nature.

Then came the impact of European settlement of North American.  With it they brought domesticated livestock to our North American habitats.  Domestication allowed us to control our food sources by concentrating our animals, but it also allowed pathogens (bacteria, viruses, protozoan, parasites, etc.) easy access to greater numbers of hosts.  When these oxen, cattle, horses, sheep, pigs and goats crossed the Atlantic, they contained many “stow-away” pathogens.  Cattle, sheep, goats and oxen were biological packages full of organisms never before found in North America.  The settlers themselves were similar biological packages, as they carried diseases to an immunologically naïve population of Native Americans.  Millions of native South, Central and North American people suffered the impact of these foreign pathogens.  I speculate this same foreign pathogen-naïve population syndrome impacted all ungulates (especially bison) in these hemispheres.

So, what are the implications for bison? If you jump forward in time, around 1850s, the bison population was estimated to be somewhere between 30 and 60 million animals.  The domesticated livestock species, along with their biological packages introduced to the West, allowed the pathogens to adapt to these new and different species.  BVD, IBR, PI3, BRSV, TB, Johne’s, mycoplasma, leptospirosis, staph, strep, internal and external parasites and probably Pasteurella found a plethora of new ways to reproduce and spread their DNA (genes) to the demise of these naïve ungulates.  In the early 1900s, populations of deer, elk, pronghorn and other wild ungulate populations were at historic lows.  These diseases had the same impact on the wild ungulates as smallpox and measles had on Native Americans, with the military slaughter and market hunting being the final nails in the coffin of large, free-ranging bison populations.

How is this an advantage of raising bison? Here is one part of the Bison Advantage.  From a high of 30-60 million to less than 1,000, the bison that survived the introduction of new pathogens and market hunting were indeed those bison that had a genetic resistance to these pathogens.  As a wildlife veterinarian for more than 25 years, I have sampled wild ungulates across the western states.  All wild populations show exposure to these introduced pathogens without large detrimental effects, yet tens same pathogens remain of utmost importance to the livestock industry.  Producers have never bred cattle, sheep or other domesticated species for disease resistance.  Vaccine manufacturers have curtailed the need for suck selection in livestock.  Thankfully, this imposed genetic resistance to these diseases allowed the remaining bison to thrive in the world of novel diseases. You have this genetic resistance to most of these pathogens in your bison.  Some pathogens, such as MCF, anthrax and TB that were recently introduced into this country are problematic.  But, all in all, our bison are hardy and genetically equipped to handle exposure to many of these pathogens.

Additionally, the bison advantage encompasses another trait. With thirty to sixty million bison pre-European settlement, bison were the largest population of wild ruminant species to ever inhabit the earth at one time.  How could this work as a Bison Advantage? We are told that North American habitats are deficient in many nutritional areas.  Low copper, phosphorus, calcium, magnesium, protein or energy during certain times of the years.  How many of you have heard that from extension agents? It is based on these domesticated Euro-Asian species and based on healthy production animals.  It has been proven that bison have a strong anabolic/catabolic cycle based on day length (anabolic means build up – catabolic means tear down).  Actually, all wildlife species in the northern hemispheres rely on this cycle for survival. It relies on the animal’s ability to have a strong anabolic cycle in spring, summer and early fall and survive nutritional deficiencies in the winter with the nutrients they stored during the anabolic cycle.

After studying deer for many years, Aldo Leopold, who wrote the “bible” of ecosystem management, Sand County Almanac, surmised that “the only thing that keeps deer alive in the winter is the thought of spring.” A female bison can start putting on weight in early spring, have a calf, nurse the calf, breed back, put on weight and then over winter, lose some of her body condition.  The cycle starts over in the spring.  Literature now recognizes that bison are excellent fiber digesters, recycle nitrogen (reducing the protein requirements), have a slow turn-over time in the rumen (greater digestibility), are meant to lose a body condition score or so over winter and yet remain highly productive.

Preliminary studies show that bison may recycle other nutrients during their catabolic period. The recycling may also include macro and micronutrients.

I a not advocating a non-vaccination or a no winter-feeding credo to bison producers. I am asking them to look at their animals with a greater understating of what a magnificent animal they manage and what the bison truly need or want from us.  When health problems arise, it is always easier to treat the symptom and not the problem.

With bison, we should take a closer look at the reason for ill health. How did we allow the pathogen to prosper at the expense of our bison? My two credos are: first do no harm and second, healthy habitats produce healthy bison. 

The only constant in this world is change.  WE must do all we can in this business to better understand this amazing creature under our care and not be afraid to implement those changes that benefit both the bison and us.

So, if you didn’t take a vacation this year, don’t blame your bison.

Author’s final thoughts (2018): Now we have the complete genome of the bison mapped.  Eureka, right? No! It is great we have it mapped, but what good does it do the average producer? We have the question about cattle genetic introgression into our herds.  This may be relevant to free-ranging federal and state “historic” herds but may not carry the same relevance to the average bison producer.  By the way, we still can’t say for certain the definition of a “pure” (I hate that word) bison.  There are three point two billion (that is billion with a B) base pairs in bison and cattle DNA.  Which genes did our bison share with cattle when the species separated 1.2 million years ago? Remember, we humans share 98% of our genes with chimpanzees, or should I say, chimpanzees share 98% of their genes with us. Two percent sure makes a difference.

Cattle and dairy producers can take a DNA sample from a calf and determine size, growth and performance, milk production, longevity and many other genetically influenced factors.  WE are not close to that level and may elect not to structure herds for just one or two genetic traits.  Cattlemen have the luxury of millions of animals that have been genetically tested and thus, can compare selected genes and traits.  The bison producer does not have that kind of information.  We are a long way away from being able to select genetics for specific traits. 

Bison One Million is a great concept FOR THE BISON.  Bison went from an estimated 30-60 million down to less than a thousand.  If you read the past history and literature of the demise of the species, it would be justified for us to be proud of this new goal.  The bison deserve to share our world and habitats in numbers that we can all be proud of.

As I look back on these articles, it makes me delighted and humbled that I was able to work with and on this amazing genetic conglomeration we call a bison.