Beef producers can lower feed costs by extending the grazing period and reducing the
need for harvested forages. Complementary forage systems extend the native range
grazing season; wheat pasture is common in the southern portion of the High Plains.
Anecdotal reports have been made concerning lowered fertility in beef cows bred on
lush forage such as wheat pasture; however, ruling out other possible causes of low
fertility is difficult.
In lactating dairy cows, fertility is lower during consumption of high-protein diets
that result in high blood urea nitrogen content. Lower uterine pH that in turn affects
embryo survival is thought to be the general mechanism responsible for lower fertility.
Little information is available on the fertility of beef cows consuming high-protein
diets. Therefore, the objective of this study was to compare pregnancy rates of springcalving
cows consuming either wheat pasture or native range before and during the
early breeding season.