IBC2000-8 Production 

Successes and Failures in Feeding Bison Bulls*

*Transcribed text edited from the audio-tape of the presentation

John Grinde, DVM
Blindman River Feeding and Bull Testing Station
Bluffton  AB  Canada

The following article was originally presented at the International Bison Conference in Edmonton, Alberta in August 2000.  The conference covered a wide array of bison topics including production, marketing, genetics, history and much more.  This article has been reprinted with the permission of the IBC2000 Chairman.

Background Information

We moved from the beef industry to bison, and still have a beef cow herd. The bison feedlot has capacity of about one thousand head, most of which are custom fed.  In my operation I feed a silage based ration in the winter. It gives me complete control over the intake and cuts down the waste considerably. I have been wary of feeding silage in the summer because of the spoilage. I have tended to stay away from  screenings and instead feed a barley based product. It is more nutritionally dense and I can control their intake. I have also found it less expensive in the long run than feeding screenings.

My silage feeders are in the pens. This serves two purposes. I must drive in every day to fill them and at the same time I can have a good look at the animals on a daily basis. There is about two feet per animal bunk space in the feeders.  My pens are quite large, about 400-500 square feet of pen space per animal.  I feel this makes a difference as to how happy the bison are. They like a large pen that allows them to run together as a group.

Successes and Failures in Feeding Bison Bulls

Everyone knows when they have had a failure, it is easy to see and talk about.  But success is much harder to measure. In the bison business there are no yardsticks to measure against. We know little about bison specific feeds or target gains. Because of this trial and error education, failures are much more common than successes. Some of the lessons I have learned are:

wBackgrounding bison on grass, in high stock densities held back by electric polytape, does not work. In my operation it was a complete disaster - it works for a day or two then is destroyed. I can extend my grazing season and put on 1.25 lb. per day successfully on grass but intensive grazing for bison does not work. I can make more dollars per acre running beef cattle at high stock densities than I can bison bulls.

wSmall calves, 260-300 lbs., coming into the feedlot have a high mortality rate from starvation. In my first
year I lost many of the small  calves to this and did not know the cause until I performed a postmortem. I now take the little ones out right away and bring them up to a pen behind the house where they are given a lot of TLC and a nutrient dense ration. Our death loss has dropped to zero. If you wait even a month it is too late. I recommend this practice. 

wThe ability to control death loss is also a problem.  Our death loss is less than one percent. Perhaps that is what we will need to live with.  Are there disease entities unique to bison? Sometimes it seems that most necropsy reports  state: no diagnosis . Again, research is needed.Stress is related to disease in all species, bison are very  susceptible to stress. How does this affect disease patterns and symptoms ?

wFig. 1 depicts the distribution of daily gains in a pen of 163 bison bulls over a period of  10 months. All bulls were given a warm up ration for a month and then weighed and sorted into two adjoining pens. Each group averaged 450 lbs. They were all fed the same silage ration throughout the winter (311 days).

Average daily gains are on the horizontal axis; percent of the group on the vertical axis. Three groups are plotted- the entire group; and two subgroups, each of which is from a different herd of origin.  The resulting graph is called a bell curve and is typical of all biological traits.

One group averaged more than 2 lbs. per day (excellent genetics) and the other averaged 1.82 lbs. per day. As you can see the results are considerably different, even though all the bison calves started out pretty much the same. That  ¼ lb. per day may make the difference between making money or losing it on those bulls. Knowing this, even the finest herds have a bell curve from best to worst. You will get not only the excellent animals but the bottom as well. Genetics has much to do with the bottom line in the feedlot. Also note that the best bulls in each group are better than the average of either group and the poorest bulls in each group are truly poor performers.

wGenetics in the beef industry are similar to the bison industry. In beef, maternal traits rate 9 points, feedlot traits, 5 points and carcass traits, 1 point. Out of a scale of 15, maternal traits make up 60% of the economic value of that animal. In bison this should be even higher because of the longevity of the cows (20-30 years), and their efficiency in converting forage. Should this ratio be 20:5:1 for bison?  Unfortunately, people are not selecting bulls based on maternal traits. Most ranchers are doing single trait selection for their bulls based on growth. We look for conformation but select on growth. We are all guilty of this. We have to start selecting on maternal traits, keeping good maternal records and downplay the feedlot value.

Final Remarks

We need more research in many areas. We have no standards to measure success against. To get these standards we need research not just in marketing but in feeding and genetics as well.  This is very important to our young industry.

Click blue icon for full view of graph

Fig. 1.  Performance (average daily gain) of two groups (1: n = 20; 2: n=22) of grain finished bison fed a silage based ration compared with the group average (n=163).