Improving Sustainability of Cow-Calf Operations with Natural Forage Systems
Our primary objective was to determine if labor and purchased inputs could be reduced and sustainability and profitability improved by matching lactation (i.e. calving and weaning) with nutrient content of grazed forages and/or by extending the grazing season in beef cow/calf systems. Previously, most research and production systems had attempted to match the forage to the cow with practices such as seeding range or pasture land with non-native grasses to meet a nutrient void of cattle in range plants.
Two projects have contributed to the objective. In project 1 during 1994 through 1999 cows were calved beginning March 15 (traditional calving date) or June 15 (nontraditional calving date) at the University of Nebraska Gudmundsen Sandhills Laboratory. The June calving date matched the high nutrient lactation requirements of the cow with high nutrient content of immature growing plants. March calving cows were fed hay January through mid-May and were grazed on rangeland mid-May through December. June calving cows grazed rangeland year long except during harsh winter weather. Calves were weaned at the same age in October and January for March and June calving systems, respectively. Total input use was monitored and output determined for March and June calving systems.
Project 2 is using weaning date as a means to match nutrient requirements of lactation with forage nutrients in a March calving system. Beginning in 1997 through 2001 calves from March calving cows will be weaned in August or November and will graze range year-long, except during calving March through mid-May. Inputs and outputs are being monitored as described for March and June calving systems. Findings for project 1 are summarized below:
Item March Calving June Calving
Hay fed, lb/yr 3947 227
Supplement fed lb/yr 96 154
Pregnancy rate, % 94.8 91.9
Weaning rate, % 88.8 89.0
Steer weaning weight, lb 480 421
Price/cwt. for weaned steer calves, $ 84.43 97.46
Gross value/ weaned steer calf, $ 410.00 409.00
Cost/ weaned steer, $ 252 175
Net/weaned steer, $ 158 234
Price/cwt for weaned heifer calves, $ 74.78 84.53
Gross value/weaned heifer calf, $ 348 342
Net/ weaned heifer calf, $ 96 167
(Note: Prices for calves are averages from western, northeastern and eastern Wyoming markets 1992-1999. Costs did not include returns to land livestock or management)
Key results are that by matching lactation with nutrients in grazed forages by adjusting calving date, nearly 2000 pounds of harvested feed was replaced by grazing and net returns were increased about $80 and $70/head for steer and heifer calves born in June compared to those born in March. Results from project 2 are not complete enough to report trends or impacts at this point in time.
We estimate that concepts and results of our project have been presented to 3,000 to 4,000 people in each of the last five years. While the interest in our work is note worthy, the greatest impacts may be on the beef industry itself. It is our assessment that we have brought a focus on grazing and management systems and practices across the United States that reduce production costs, increase returns, improve sustainability, bring greater attention to the importance of holistic management, and inventorying resources. We estimate that as many as 250,000 head of cattle may have been impacted to date by our project. If a $75/calf increase in returns were realized for each calf impacted the beef cattle industry would realize an increase in returns of over $18 million annually. In addition the major reduction in the need for harvested forage has improved the environment by reducing use of fossil fuels. The heaviest grazing pressure for the June calving system occurs during the dormant season for the range a time when grazed forage can better withstand the pressure.