I was talking to a retired beef producer who owned a purebred Charolais herd back in the 1970s. He reminisced on how winter-hardy the breed was compared to more traditional breeds of the time and how the cows calve out huge white calves. Eventually, he got rid of these cows and replaced them with easier-calving breeds, because he spent many sleepless nights assisting the former first-calf heifers during the calving season.
It’s hard to say whether this is why I don’t see as many Charolais cattle as I once did, but I have learned that many first-calf heifers regardless of breed have special challenges. To help overcome them, I recommend providing a good overwinter feeding program, especially designed for young heifers along with a healthy dose of “tender loving care” — TLC.
One of the first challenges many first-calf heifers face is the stress of giving birth to their first calf. They suffer a heightened incidence of calving difficulties — clinically known as dystocia — compared to mature cows. Even when dystocia is not an issue, replacement heifers take longer to return their uterine tract to normal (involution) and return to active estrus cycles; all the while nursing a newborn calf and still growing themselves. That’s why many producers breed and calve-out first-calf heifers two to three weeks before the rest of the cow herd. It helps to synchronize their next breeding/calving season with the mature cow herd as well.
Reproductive success (or failure) for these first-calf heifers is largely determined by their maintenance or achievement of an optimum body condition score (BCS) ,which on the nine point U.S. scale is five to six (re: one = emaciated and nine = obese) by calving time. This goal parallels a desired growth rate of one lb./head/day and reaching 85 per cent mature bodyweight. Conversely, thin heifers (BCS under four) and over-conditioned ones (BCS over seven) suffer a greater incidence of dystocia, weak newborns and a higher failure rate to return to estrus, which encompasses lower pregnancy rates.
Maintaining/achieving a BCS of five to six depends on how well we feed these young cows by supplying their essential nutrient requirements geared for vital functions, milk production, growth and reproduction.
I find that meeting primary nutrient requirements for bred first-calf heifers is pretty simple. They require about 10-20 per cent more energy, protein and other nutrients comparatively to mature cows, yet have about 20 per cent less dry matter capacity (eat less). In the end, I think this difference often evens out among young and older individuals in the cow herd, because big mature cows need just as much or more nutrient on an absolute basis, particularly toward the calving season.
By no means do the actual formulas of first-calf heifer rations need to be fancy. Consider the following common three rations for bred replacement heifers approaching calving and maintaining a BCS of five to six, while gaining 1.5 to two lbs./head/day. Based upon current commodity prices all three rations should cost no more than $1.50-$2 per head per day to feed:
(1) Free choice (20 lbs.) mixed alfalfa-mixed grass with two to three pounds of barley or corn, plus two to three ounces of a commercial 2:1 cattle mineral.
(2) 20 lbs. of barley or corn silage, 15 lbs. of alfalfa-grass hay and two to three lbs. of a 14 per cent protein cow-calf screening pellet.
(3) 30 lbs. of silage and 10 lbs. of mixed alfalfa-grass hay and one to two pounds of a commercial protein supplement.
These are good first-calf heifer overwintering diets, where modest adjustments can be made to simply add extra nutrition such as adding more grain to promote BCS or increase the daily growth rates. Other changes may include changing the basic 2:1 cattle mineral to breeder type mineral in order to facilitate estrus cycling. The only ingredient in this diet that is hasn’t been mentioned above is TLC. However, it’s a very important constituent that can be easily implemented and managed by beef producers.
A good illustration of this: despite it being a dry year on the Prairies, an early harvest produced lots of economical straw that could be used as clean bedding for heifers in dry lot. In a similar fashion, I know of many producers that purchased portable windbreak panels made up of wood-planks and oil piping in order to reduce the upcoming windchill upon replacement heifers’ backs. Last, I just talked to one producer that cleaned and fixed his waterers for a group of segregated heifers to increase the flow of fresh available water during the winter.