Cow Condition and Reproductive Performance
It has been understood for decades that reproductive performance is the most important factor affecting production efficiency of a cow-calf enterprise. To maintain a yearly calving interval (one calf every 365 days), a cow must re-breed in 80 to 85 days after calving. With the nutrient priority of beef cattle being body maintenance, growth, lactation, fetal growth, breeding, and body reserve according to Short et al. (1990) indicates that reproduction is low on the list. Body condition score at parturition has been implicated as the single most important factor affecting postpartum interval to estrus and pregnancy in multiparous cows.
Walker, Julie and Perry, George, "Cow Condition and Reproductive Performance" (2007). Animal Science Faculty Publications. 23.