Cow Calf: Early Lactation Considerations
The early lactation period is the time of highest nutrient requirements for the beef cow. Providing the nutrients needed is crucial to enable the cow to nurse the calf as well as stay in the body condition needed to be able to rebreed within 80 to 85 days after calving. According to the National Research Council (NRC) 1996 edition recommendations, a 1200 lb cow producing about 15 pounds of milk per day at peak lactation will require a diet containing about 9.5% crude protein (CP) and about 58% total digestible nutrients (TDN). First calf heifers have an even higher nutritional plane, they need a diet with about 10.5% CP and 62% TDN.
Remember that there is a biological priority for nutrients, or a hierarchy of nutrient use. Body maintenance requirements will always be met first. If there are sufficient nutrients beyond that then growth is the next priority. This explains the higher nutrient requirements for those first calf heifers because they are still growing. After growth needs have been met, nutrients in the diet are allocated for milk production. Last, after all other nutrient needs have been met, is the requirement for reproduction. Since rebreeding is a management consideration within the early lactation period, the cow-calf producer can’t afford to be short on nutrients during this period.