Which Has The Advantage: Late Winter Or Fall Calves?

MT. VERNON, MO.
   Cow-calf raisers in southwest Missouri are gradually moving toward a higher percentage of cows calving in late August to November according to Eldon Cole, a livestock specialist with University of Missouri Extension.
   “Years ago most cows in the area calved in the first four or five months of the year. Little-by-little there’s been a shift towards more fall calves,” said Cole.
   Part of this change may be due to the fescue toxicity problem and poor rebreeding in the heat of the summer according to Cole.
   “The cows that calved after late-March often did not breed back in hot weather due to lower cow and bull fertility,” said Cole. “Elevated body temperature from endophyte infected fescue receives much of the blame for that problem.”
   Ultimately, those calves are bred for a late summer or fall-born calf after breeding when the weather cooled down. Cole speculates that this may have also led to the habit of many farmers leaving the bulls out year round.
   Farmers quickly discovered merits to September calves. For example, fall born calves, especially those in late August and September, run lower in birth weight than late winter-spring calves (by up to five pounds). This reduces calving problems, especially in heifers.
   “Fall calves don’t freeze, have short ears or tails. They have fewer scour problems and really take off and gain well after green grass arrives in the spring. Many years, the fall-born calves will outsell the spring-born calves,” said Cole.
   Other advantages to the fall-born calves include: the dams rebreed easier; bull expenses are spread out over more cows with two distinct breeding seasons; more flexibility in the marketing plan; opportunity to save replacement heifers and breed them at 20 to 22 months so they calve at 30 months.
   Calving heifers at 30 months allows them to be developed more slowly, but some may get too big in that extra 6-month growing period.
   “Farmers, who are concerned their cows are too large, probably should try putting them to work earlier in life. Calving at 24 months helps accomplish that,” said Cole.
   According to Cole, feedlots like to have a more even set of calves to select from all 12 months of the year rather than have the markets crowded with calves in the fall months of October, November and December.
   From a marketing standpoint, herds under 60 or 80 cows may be in a quandary as they consider the splitting of their cows into a spring or fall herd.
   “If you split the herd you will have smaller groups to sell and we all know the power of larger drafts going through the sale ring. You could be better off deciding which season matches your forage, labor and other resources and then stick with one season,” said Cole.
   A common concern for those looking at fall calving is the extra feed needs of a cow that is nursing a calf during the period when pastures are not lush and could be covered with snow.
   Feeding stored or purchased forage or concentrates adds to the overall cost of the cow.
   “On the bright side, those fall calving cows typically put on extra weight on summer pasture after their calves are weaned in June. Thus, they calve in at least a 6, sometimes a 7 body condition score,” said Cole.
   Fall born calves seem to be more efficient at using supplemental feed than their spring counterparts. It’s good to at least provide them high quality legume/grass hay in a creep area.
   Full-feeding a concentrate or protein feed in a creep may pencil out some years, but a limit-fed creep ration appears to be the most economical system to follow according to Cole.
   “The use of two or three pounds of corn gluten feed, soybean hulls or distillers dried grains has proven helpful in keeping the calves gaining. If the calves are not given supplemental feed and the cows are marginal milkers, by March it will look like the only thing that grew during the winter was their hair,” said Cole.
   Excellent spring and early summer pasture provides a gain opportunity for fall calves when weaned in June. As a rule, June-weaned calves also have less respiratory problems than those weaned in October and November. This is another plus for fall-borns.
   “Many factors must go into making the management decisions on selecting a calving season. Over the years, extension recommends for southwest Missouri to not calve from May through August. Other considerations may change that recommendation,” said Cole. Δ