Russ Daly: Foster calves in the beef herd – worth the risk?

If you’ve raised beef cattle for any length of time, you’ve likely encountered the heartbreak of losing a young calf out of a good mother. Calves get stepped on and break their legs, get caught out in freezing cold, or drown in a stock dam. Things happen.

This loss is unfortunate, but as with any downturn, cattle producers frequently look for any way to make a bad situation a little better. If the lost calf was young enough, and the mother is a good cow and milking well, the thought process could go, “Maybe that cow could raise someone else’s calf!”

This is a great time to have a set of twins handy! Of course, that’s usually as likely as hitting the winning lottery ticket on a given day. Many producers wishing to see this calf-raising scenario play out will turn to the local auction market or neighboring farm. After all, there are situations where the opposite happens – a calf loses its mother or a twin calf loses the coin flip and goes down the road. These create tempting opportunities for a producer looking for a foster calf his cow can raise.

I’m not sure how often the foster calf scenario plays out any more among our beef operations, but I do still hear the stories. A lot of it has to do with economics and how expensive a proposition the foster calf purchase ends up being. I also feel, however, that more and more cattle producers understand the risk of bringing in a new young calf into their herd.

That risk was documented in an SDSU case report. It’s several years old, but the lessons are still as fresh now as they were back then. A South Dakota commercial beef herd had enjoyed successful calving seasons for several years’ running, and the start of this particular season was no exception. But halfway through the 90-day calving season, life got messy for this operation’s calves and their caretakers. A scours outbreak hit, spreading to more than 70% of 200 calves born. During one particular 2-week period, 80-90% of the calves born became sick.

An investigation ruled out weather and problems with colostral immunity, and discounted the effect of the calving pastures. A record review, however, revealed one significant event that occurred about a week prior to the abrupt rise in scours cases: foster calves from outside were added to the herd.

What is it about new foster calves that could set off such an outbreak? Any animal from another population has their own set of organisms—viruses, bacteria, etc.—that are at least somewhat different from those in the recipient herd. Cryptosporidiosis is a prime example of a scours disease that, if new to a herd, spreads through calves like wildfire when the herd has no prior “experience” with the germ. These foster calves are also usually stressed due to the events of their young lives, increasing the frequency and number of the germs they shed.

Calf health is important enough to a cow-calf herd that the best advice is to just simply not bring in new foster calves. But if it’s absolutely necessary, there is a right way to accomplish this.

First, isolate the new calf and his “stepmother” from the of the herd for at least four weeks. During this time, the level of germ shedding will decrease in the new calf. It also means that more of your calves will be older and better able to deal with a germ the newcomer might bring in.

Your vet should get a sample from the new calf for BVD – it’s easy and inexpensive. Bringing in a calf persistently infected with BVD virus would have devastating consequences on the herd for years to come.

But after all this, one still needs to be realistic about the risks that will remain. Johne’s Disease can be brought in with a young calf and not become apparent until years later – making foster calves a bad choice to keep around as replacement heifers.

Bringing in a foster calf is an example of a mostly ill-advised decision that can be properly managed if absolutely necessary – but only with foresight and veterinary advice.