Submitted to: American Society of Agronomy Branch Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 2/1/2002
Publication Date: 2/1/2002
Citation: Arthington, J.D., Roka, F.M., Jullahey, J.J., Coleman, S.W., Lollis, L.O., Muchovej, R.M. 2002. Integrating ranch forage production, cattle performance and economics in ranch management systems. American Society of Agronomy Southern Branch Meeting, February 3-5, 2002, Orlando, Florida. P29. Interpretive Summary:
Technical Abstract: Decreasing cattle stocking densities is one practice that has been suggested to improve surface runoff quality draining into Lake Okeebhobee, Florida. A holistic approach is needed to address both production and economic implications associated with lower animal densities. The objective of this study was to determine the effects of stocking rate on cow-calf performance, forage yield and quality, and the ranch's financial position. Experimental pastures have been established on a typical south Florida cow-calf operation. Stocking rates 0.57, 1.00, and 1.34 ha/cow on summer pastures and 0.93, 1.62, and 2.15 ha/cow on winter pastures corresponded in high, medium, and low rates, respectively. Cow body condition scores, pregnancy rate, and calf average daily gain were used as measures of animal performance. Forage utilization was estimated by measuring the difference between forage yield inside grazing exclusion cages and the available forage outside the cage. Crude protein and in vitro organic matter digestibility measures were used to estimate forge quality. Partial budgeting and a cow-calf simulator were used to estimate economic implications of reduced stocking rates. Forage yield, utilization, and quality were not significantly affected by stocking rate. While cattle in the medium and high stocking rates had lower body condition scores following the winter grazing period, no significant impacts were found on pregnancy rate and calf gains. Production, as measured by pounds of calf weaned/ha of dedicated land was improved (P<0.03) for high compared to medium and low stocking rates. Ranch revenues decrease one-for-one as stocking rates decrease. Net income decreases at an increasing rate with declining stocking rates as fewer brood cows are left to support the ranch's fixed cost structure.