Bullers are, fortunately, a rare, sporadic occurrence in western Canadian feedlots and backgrounding operations.
When dealing with cases of steers mounting other steers, one must bear in mind the economic loss to the entire pen when frequent riding occurs. Because the incidence is so sporadic (one to six per cent in U.S. feedlots), no hard and fast research has been done as to the exact cause. But there are many factors which potentially contribute to riding.
Each feedlot’s buller problems can be unique, which is why a customized plan for dealing with these problems should be developed with your feedlot veterinarian.
There seems to be higher incidence of bullers in larger, but crowded, pens. We almost never see the condition in small pens of 10 or 15 head, which is why moving bullers to the chronic pen can often be a solution.
In a new pen, it may take up to 60 days to establish a social hierarchy and of course steers penned next to heifers are a problem especially if heifers are not on MGA and are cycling. Bulling activity will naturally increase a bit in the late summer and early fall as it is associated with warm days and cool nights.
Implants have always been implicated when there is crushing or abscessation resulting in inconsistent absorption. A great deal of time and effort has been spent in teaching feedlot processing crews as to proper technique. A number of implant guns now have retractable needles and one (the Revalor gun) has a simple metal hoop which pushes the gun away, making it virtually impossible to crush implants. Crews should use alcohol- or disinfectant-impregnated rollers to clean needles quickly between usage. Every year it is best to review the operation’s implant technique because sometimes, in the interest of speed, shortcuts are made. Common-sense things like not implanting through manure, dirt and debris, as well as using the proper location (middle third of the ear for all implants) is critical. Some implant techniques such as bunched, crushed or implants too close to the head increase riding. It is also critical to have a defined implant protocol and not use, for instance, too high of a TBA implant when, for example, the energy in the ration is low or cattle are grazing.
Inconsistencies in feeding times and crowding lead to bored cattle and the propensity to initiate riding. Be consistent in feeding, maintain functional watering bowls, and allow as much room as possible to prevent a flare-up of riding behaviour. Larger feedlots often implement at least two- and even three-times-a-day feeding. This minimizes digestive upsets and ruminal acidosis, and has a secondary benefit of reducing bullers.
Bunk management is critical for several reasons, including keeping the buller problem to a minimum. The main idea is to not run out of feed in the bunk as cattle can start pushing when feed arrives and riding can be the result. Sudden ration changes lead to increased riding so most ration changes should be made over several days. This also minimizes digestive upsets.
There has been a higher incidence of riding in Holsteins, but this may reflect past husbandry practices with calves being individually housed for the first few weeks of life.
Stags or intact bulls can cause numerous problems in the feedlot, not the least of which are bullers. They initiate lots of riding. Conversely when castrated, they may become the target of riding.
If we knew the weight loss and injuries caused by stags in the feedlot, the numbers would be shocking. All feedlots try and avoid the purchase of these animals, but there are always some cases to deal with. Make sure they are castrated properly and check closely for stagy animals when processing. This may require palpating every steer coming in so if identified they can be dealt with right at processing. Deal with them as soon as possible as the best time for reintroduction is when the pen is being processed, moved, or reimplanted. Reintroducing animals from the chronic pen or adding new arrivals is best done when the whole pen is being disrupted such as reimplantation time or during a storm. The premise is not having the new cattle stand out as being different.
Some feedlots over the years have tried masking the supposed hormonal smell with a different smell, such as a perfume oil. In my experience, this only further peaks the cattle’s natural curiosity and riding behaviour may start.
Some feedlots have constructed buller guards so these animals can find some relief by running under them. This works for social bullers, which are less dominant and try and avoid riding behaviour. It does not improve the bulling rate but the guards may prevent injury. If the same cattle are always found under these guards they still should be pulled as feed and water consumption are greatly altered. True bullers, which totally stand to be ridden, should be pulled and in most cases remain in the chronic pen for the rest of their days. These true bullers will do well in a small pen and can live out their days comfortably eliminating all the chaos they cause in a full large pen and gains become respectable.
Watch for unusual cases such as hermaphrodites (intersexes) and freemartin heifers (which may look like steers including having a sheath) that can initiate riding behaviour. Pens of heifers not on MGA (a progesterone product to reduce cycling) will, of course, cycle regularly. The problem here is differentiating normal cycling behaviour from excessive cycling that you might get with a cystic animal. Watch for excessive abrasions over the back or apparent knuckling in the back legs that would indicate back problems. These animals should be pulled and allowed to convalesce (and may or may not return to the home pen).
As with everything in the feedlot good observation skills and attention to detail will minimize bullers and reduce the decreased weight gain or injury they cause to the rest of the pen.