VTechWorks staff will be away for the winter holidays starting Tuesday, December 24, 2024, through Wednesday, January 1, 2025, and will not be replying to requests during this time. Thank you for your patience, and happy holidays!

Browsing by Author "McKinnon, Bill R."

Now showing 1 - 9 of 9
  • Thumbnail Image
    Budget Analysis of Spring, Fall with Winter Clean-up, and High-Fertility Fall Lambing Systems in a Simulated Fixed Forage Resource
    Andrew, Shelley Lewis Jr. (Virginia Tech, 1998-08-03)
    A successful business needs to generate enough cash to cover expenses, current debt, and family living expenses, pay interest on owned and borrowed capital, maintain productivity, and earn a reasonable return for the operator. Income from sheep production is generally only part of a total farm and nonfarm income. Thus options, opportunity costs, and decisions regarding the sheep production enterprise are not isolated; they affect other agricultural enterprises. Sheep production consistently returns profits to producers, which makes it an enticing agricultural enterprise. There are advantages in raising sheep in Virginia, such as abundant, high-quality forage, moderate climate, pasture improvement, and good access to markets with high demand for lamb. The disadvantages to sheep production are unavailable and inexperienced labor and operators, predators, and inconsistent market demand and supply. Sheep producers have the opportunity to choose which lambing system fits their existing operations and lifestyle. The use of economic analysis enables operator to make sound business management decisions. To compare different lambing systems (spring, fall with winter clean-up, and high-fertility fall) in a systematic way, a simulation model was constructed with a fixed forage resource of 50 acres of pasture including typical Virginia mountain pasture plus various amounts of fescue for stockpiling. The simulation included a production calendar; nutritional requirements for ewes, lambs, and artificially reared triplets; growth rates for lambs; lambing distributions; forage growth; and enterprise budgets including income, costs, and returns. A economic analysis was performed for each lambing system with average prices or with plus or minus one standard deviation for prices of corn, SBOM, and market lambs, and price differentials for market lambs across lambing seasons. Comparisons of each lambing systems produced various results. In spring lambing, only 78 ewes could be maintained on the fixed forage resource, while the fall with winter clean-up and high-fertility fall lambing system each had 115 ewes. This result occurred because of limited forage in July and August and higher nutrient requirements for spring lambing in those months. The overall nutrient requirements were higher in the fall with winter clean-up and high-fertility fall lambing than in spring lambing as a result of the increased ewe and lamb numbers. Concentrate consumption by lambs was also greater for fall with winter clean-up and high-fertility fall lambing than for spring lambing because of the increased numbers of lambs. Because of the low number of ewes and lambs, spring system produced the most hay. Labor costs were highest in fall with winter clean-up lambing because of the two lambing seasons. In the economic analysis system, each lambing was compared. With 10-year average prices for market lambs, corn, and SBOM, high-fertility fall lambing had the greatest income ($17,467), followed by fall with winter clean-up lambing ($14,695), and spring lambing ($10,358). This result occurred because high-fertility fall and fall with winter clean-up lambing had more lambs sold at higher market lambs prices than spring lambing. With 10-year average prices for market lambs, corn, and SBOM, high-fertility fall lambing had the highest cost ($7,935), followed by fall with winter clean-up lambing ($7,360), and spring lambing ($6,084). This was the result of increased ewe and lamb numbers in high-fertility fall and fall with winter clean-up lambing than spring lambing. High-fertility fall lambing had the greatest returns ($6,210), followed by fall with winter clean-up lambing ($4,025), and spring lambing ($2,028). On a fixed forage resource, increasing fertility in fall lambing clearly results in increased returns. In this model, forage availability controlled the number of ewes that a lambing system can have because of limited summer growth and had a major impact on profits. Conclusions of Tolman (1993) differed from those found within this thesis. On a per ewe basis, she found that spring lambing to yielded the highest returns whereas this thesis found that high-fertility fall lambing yielded the highest returns. A key difference between this study and that of Tolman (1993) was after weaning this thesis feed fall lambs stockpiled fescue and she feed fall lambs feed in dry lot.
  • Thumbnail Image
    Effect of Feeding Different Protein and Energy Supplements on Performance and Health of Beef Calves During the Backgrounding Period
    Austin, Robert Jesse (Virginia Tech, 2001-08-15)
    Newly received or weaned calves are highly susceptible to the incidence of bovine respiratory disease. In addition to high levels of stress, decreased feed intake and exposure to foreign antigens result in increased morbidity and possibly death losses. Four backgrounding trials were conducted to examine the effects of protein and energy supplements to stressed calves consuming different forages. Body weights, rectal temperatures and blood samples were taken on d 0, 7, 14, 28 and 42. Supplements consisted of corn or mixtures of corn and soybean meal. In trial 1, 48 heifers (average BW = 219 kg) fed fescue hay in drylot, were allotted to four treatments: no supplement, 15% CP supplement (0.5% BW), 15% CP supplement (1.0% BW) and 30% CP supplement (0.5% BW). Supplemented heifers had higher (P<0.05) ADG than unsupplemented heifers by 42 d. Heifers fed the 30% CP supplement had higher (P<0.05) plasma urea-N by d 42. In trial 2 (pasture study 1), 36 steers (average BW = 217 kg) grazed stockpiled tall fescue and were allotted to three treatments: no supplement, a 15% CP supplement (0.5% BW), and a 15% CP supplement (1.0% BW). After wk 1, ADG was lower (P<0.05) for supplemented calves. At the end of the trial, steers supplemented at 0.5% BW had higher (P<0.05) ADG than steers supplemented at 1.0% BW. Glutathione peroxidase levels were lower (P<0.05) for supplemented steers on d 28. For trial 3 (pasture study 2), 48 steers (average BW = 202 kg) grazed stockpiled tall fescue and were allotted to three treatments: no supplement, corn (1% BW), and 15% CP supplement (1% BW). After wk 1, ADG was higher (P<0.05) for steers supplemented with corn. Steers supplemented with 15% CP supplement had the lowest (P<0.05) ADG after 7 d. At d 42, supplemented steers gained faster (P<0.05) than unsupplemented steers. For trial 4 (pasture study 3), 48 steers (average BW = 202 kg) grazed stockpiled tall fescue or fescue-alfalfa and were allotted to two treatments: no supplement and a 15% CP supplement (0.5% BW). During wk 1, steers grazing fescue had higher (P<0.05) ADG than steers grazing fescue-alfalfa. During wk 1, supplemented steers had a higher (P<0.05) morbidity scores. At d 42, ADG was higher (P<0.05) for supplemented steers. No consistent differences were detected in forage and blood serum mineral concentrations in all trials. Glutathione peroxidase activity increased (P<0.05) for all trials on d 14, regardless of supplementation. Supplementation improved ADG by d 42 but did not affect overall health status of calves in all trials.
  • Thumbnail Image
    Getting Started in the Cattle Business in Virginia
    McKinnon, Bill R.; Snodgrass, Henry S. (Virginia Cooperative Extension, 2005-09-01)
    The beef industry consists of various segments of production. The function of this diverse industry is to produce a live beef animal from which high quality beef is ultimately delivered to the consumer.
  • Thumbnail Image
    Getting started in the cattle business in Virginia
    McKinnon, Bill R.; Snodgrass, Henry S. (Virginia Cooperative Extension, 2000)
  • Thumbnail Image
    The Virginia Beef Cattle Simulation Model: A bio-economic simulation program modeling the interactions among reproduction, forage availability, nutrition, growth, and marketing in beef cattle
    Schick, James Henry (Virginia Tech, 1999-03-29)
    The Virginia Beef Cattle Simulation Model (VBCSM) is a user-friendly, dynamic, stochastic computer program whose objective is to serve as a decision-aid for Virginia cattlemen dealing with complex management issues such as whether to retain weaned calves through the stocker growth stage. Its five source-code modules are reproduction, forage, nutrition, marketing, and a tool that randomly assigns values to variables from appropriate statistical distributions. The VBCSM contains production statistics for 12 breeds, 21 forage species, and three Virginia agro-ecological zones. It simulates at the animal level using information obtained from program dialog. Help can be activated on each dialog page. It is event-driven on a daily time increment. The reproduction module simulates puberty, conception, abortion, parturition, dystocia, lactation, pregnancy testing, culling, within-herd replacement female selection, open or pregnant replacement female purchases, cow and calf mortality, and weaning. The forage module simulates daily pasture growth dependent upon month, precipitation, erosion, pasture maintenance, grazing system, farm location, weed infestation, and slope. This module interacts with the nutrition module to calculate each animal's forage intake, supplemental feed requirements, and daily gain or loss using National Research Council equations. The marketing routine sells the weanling calves to the stocker herd and sells stocker calves, orphan calves, and cull cows through user-specified markets, including the Virginia Tel-O-Market auction. After simulating for eight years to achieve equilibrium conditions, the VBCSM provides an income statement for the cow-calf operation and a partial budget for net income or loss from the stocker herd for up to three years. VBCSM was rigorously tested using a mathematical model with two calving seasons, three lengths of breeding season, four culling policies, and a year effect. Descriptive statistics suggest that the program code works in a consistent manner. However, several potential programming inconsistencies were discovered. Simulation results indicate that fall calving may be more profitable for Virginia cattle producers than spring calving for weanling calf production, but a spring calved stocker program may be more profitable that a fall calved stocker program. Perhaps, VBCSM will help cattlemen to enhance their profits by more efficient market planning and utilization of production resources.
  • Thumbnail Image
    Virginia Cow Herd Performance Check-Up
    McKinnon, Bill R.; Hall, John B.; Covey, Thomas W.; Greiner, Scott P. (Virginia Cooperative Extension, 2005-09-01)
    An annual analysis of various herd performance measures can serve as a yardstick against which to compare past and future years' performance.
  • Thumbnail Image
    Virginia cow herd performance check-up
    McKinnon, Bill R.; Hall, John B.; Covey, Thomas W.; Greiner, Scott P. (Virginia Cooperative Extension, 2001)
  • Thumbnail Image
    Virginia winter-lambing budget
    Umberger, Steven H.; McKinnon, Bill R. (Virginia Cooperative Extension, 2000)
    Winter lambing is used on farms where adequate winter feed supplies, experienced labor, and covered facilities for lambing are available. In the Southern Piedmont and Southeastern Virginia, where summer temperatures and humidity are high and the quality of summer pastures is low, winter lambing is considered the best option for market lamb production. Winter lambing occurs during the months of December, January, and February. It is more labor intensive than spring lambing and requires a higher level of management for breeding, lambing, and feeding. The profitability of winter lambing is tied closely to the price of grain and the number of lambs marketed per ewe annually. Winter-born lambs must be weaned at two to two and one-half months of age and fed a high concentrate diet to reach market weight before the precipitous drop in market prices that typically occurs in the late spring.
  • Thumbnail Image
    Virginia's beef industry : a study and blueprint for the year 2000
    Stanley, Thomas; Eller, Arthur L. Jr.; McKinnon, Bill R.; Wahlberg, Mark L.; Gerken, Hubert J. Jr. (Virginia Cooperative Extension, 1993)
    Beef production in the Commonwealth of Virginia has a long and rich history, having its roots in colonial times and having developed into a strong. viable industry in modem Virginia. Today, Virginia, with 1.78 million cattle, ranks 19th in the U.S. and with 735,000 beef cows, ranks 18th. Virginia's beef industry has grown and developed principally because beef cattle arc one of the most suitable enterprises to utilize pasture and forage which is found in abundance throughout most of the state. Cattle offer a means to market these feed stuffs which would otherwise have little value.