Cut out the fat
Written by: Dr. Jayson Galbraith, Bison/Elk Specialist, Livestock and Farm Business Branch, Alberta Agriculture and Rural Development
Feeding bison heifers to grade A1 or A2 requires a different approach than feeding bison bulls to similar grades. Carcasses from bison heifers often have excess fat and are prone to being downgraded to A3 and A4 grades. This article is based on a presentation given at the March 2013 Bison Producers of Alberta Wildrose Show and Sale and convention by Dr. Óscar López-‐Campos, a certified bison and beef carcass grader, Frank McAllister, with Elk Valley Ranches, and Paul Kolesar with Kickin’ Ash Buffalo products, about feeding bison heifers for achieving optimal carcass grades.
Óscar explained that bison carcasses slaughtered at any federal slaughter plant are evaluated by graders employed and certified by the Canadian Beef grading Agency. They evaluate the carcasses 24 hours after slaughter, when the carcasses have chilled to 2oC. The left side of the carcass is ‘knifed’ between the 12 and 13th rib exposing the rib eye region for evaluation. After 20 minutes of time for the meat to bloom (come into contact with oxygen), the rib eye region is evaluated for area, fat measurement, colour (redness) and texture. The entire side is evaluated for fat colour and muscle tone. These series of decisions results in a grade that can be used to sort carcasses or set criteria for payment to a producer. The criteria also attempts to estimate a yield (of lean meat) associated with them.
Grading is done at all federally inspected slaughter plants. Some jurisdictions require certain grades in order to allow import of meat. For example the EU only imports bison graded A3, A2, and A1. All other grades are not eligible to export to the EU. This has implications on the market opportunities that are available for different grades of carcasses.
At Elk Valley Ranches, Frank explained that the first point of differentiation is that the calves are sorted by gender at the time of weaning. They are kept separate right through to slaughter. At the time of weaning, in December or January, calves are all given a series of vaccinations and de-‐wormed. Then the he puts the heifers on hay/grass until they are 2 | P a g e approximately 15 months of age. At around 15 months, the heifers go into the feed yard, vaccinated and put in certain weight range pens at 75lb increments. They are fed a 66TDN screening pellet and hay. TDN is an acronym for ‘total digestible nutrients’ which is an approximate measure of the food energy available to the animal after the digestion losses have been deducted. The heifers typically go into the feed yard at between 600-‐650 lbs., and put on between 1 -‐ 1.5lbs per day. The heifers are shipped out once ready, and are not kept to an over finished stage. The cost of gain is lower on bulls, so once heifers are ready they go out of the feed yard first. The weight range of finished heifers is between 850lb for a shorter framed heifer to 925 or 950lbs on a longer framed heifer.
He has found that wood bison, plains bison crosses have been found to be 100lb higher on average over straight plains animals when they come off of grass. This is a benefit of using some woods influence on the herd.
Paul commented on his system of finishing, which is a rolled oats and hay feeding program. He is also careful about not over finishing heifers. Some marketers are considering implementing a heifer ‘over-‐ conditioning’ penalty. It was explained as allowing 100lbs of fat to be trimmed off a load of bison, and then charging the weight in excess of this at the going carcass price back to the supplier of the load. Paul said that had that system been in place on a load he sent out this past winter, it could have resulted in a $2,700.00 deduction on his cheque on that load. This works out to between a $60.00 -‐ $65.00 deduction per head. The consumer doesn’t want extra fat on the steaks or roasts, the marketer doesn’t want extra fat, extra fat is expensive to put on the animal, and now the market is signaling this through considering a financial penalty on extra fat trimmed off an over finished heifer carcass.
There is sound logic in reducing over-‐fat bison heifer carcasses. By using the proven advice provided by the experienced producers who shared their knowledge at the 2013 Bison Producers of Alberta Convention, the fat can be cut out of the system; before it’s put on.
(Thanks to Dr. Óscar López-‐Campos, Frank McAllister, and Paul Kolesar for their excellent presentation at the convention, and for the wealth of knowledge they bring to the discussion)