There are some disadvantages and perhaps a few advantages of using self-feeders. The clear advantage is the ease or convenience. The clear disadvantage is that cattle can access a great deal of feed at once. In many pen feeding situations where cattle are fed once, twice, or even three times a day, the first steer that comes to the bunk still has access to a great deal of feed.
It seems that most cattle have to get "trained" to eat differently in feedlot situations. They will probably experience some acidosis regardless. So, it is probably most critical to think about ways to minimize any negative impacts from this adjustment. In fact, whenever a step-up or grain adaptation program is followed, in essence, you are "training" those cattle to eat differently. They will go from large meal consumption with a few meals to many meals in a day and smaller amounts. This allows them to regulate the amount of starch consumed over the course of a day and hopefully prevent acute, and perhaps subacute, acidosis.
I do not have experience with self-feeders and I am not aware of data comparing self feeders to pen feeding, at least recently. I do know when I was raising Holsteins in our family feedlot on self-feeders, that it appeared to work O.K. The problem with subacute acidosis in commercial operations is the difficulty in diagnosis. For example, how do we know there is subacute acidosis? One way is to observe that there are lower dry matter intake and perhaps some other symptoms. If an entire feedlot is switched over to a new feeding system, how do you compare those intakes to a group that was not experiencing acidosis and lower intakes? You need to have random allotment of cattle, multiple pens, and different management of diets that help alleviate subacute acidosis to be able to know the real effect of subacute acidosis. We would argue almost all feedlots and all pens (perhaps all cattle) experience a level of acidosis (subacute). We attempt to manage them so these are not acute (death) cases and to minimize the negative effect of subacute acidosis.
However, this does not answer your question.
I do believe having cattle on self-feeders increases the "risk" of subacute and acute acidosis. However, Holstein steers may be a good fit for this.
I would adapt them on self-feeders by a couple of possible ways:
1) have them on full feed prior to going on self-feeders (may not work)
2) mix in dry hay at a percentage of 20% or greater initially, even though they are on self-feeders and then gradually decrease it (may not work)
3) feed dry by-products to replace a portion of the starch (probably 30 to 35% to have any effect on a DM basis (may not work)
4) put them on the self-feeder after partial adjustment to grain and hope they don't overconsume grain.
As you can tell, I am not sure of any great methods. If any other readers have experience or others have input, I would be open to methods that do work. I would also recommend a fairly high dose of Rumensin to help with variable intakes in this situation (30 g/ton on a 90% DM basis, the upper legal limit). Other methods such as feeding less processed grain or slower digesting starch sources such as grain sorghum may also fit here.
