Deciding on the use of one calving season or two calving seasons is a big first decision when producers are choosing calving seasons. Many fall calving seasons have arisen from elongated spring seasons. Two calving seasons fits best for herds with more than 80 cows. To take full advantage of the economies of scale, a ranch needs to produce at least 10 to 20 steer calves in the same season to realize the price advantage associated with increased lot size. Therefore having forty cows in each season as a minimum seems to make some sense.
Using two seasons instead of just one can reduce bull costs a great deal. Properly developed and cared-for bulls can be used in both the fall and the spring, therefore reducing the bull battery by half. Another small advantage to having two calving seasons is the capability of taking fall-born heifers and holding them another few months to go in to the spring season and visa versa. Because of this replacement heifers are always 2 1/2 years at first calving instead of 2 years old. These heifers should be more likely to breed early in the breeding season and have slightly less calving difficulty. Research has shown that these differences are very small, therefore the cost of the other six months feed must be minimal to make this a paying proposition. Many producers like the dual calving seasons because of the spread of the marketing risk. Having half of the calf crop sold at two different times allows for some smoothing of the cattle cycle roller coaster ride.
There are however a couple of disadvantages that must be considered. The producer now has twice as many nights to get up and check cows and heifers at calving time. In addition, if heifers are not bred until about 20 or 21 months of age, then they will be more than 24 months of age when they are preg checked. Open heifers that need to be culled at more than 24 months of age will definitely be penalized at the market place compared to younger cull heifers that are sold at much higher prices per pound.