Browsing by Author "Brown, Carl A."

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    An analysis of the influences of changes in herd size and certain other management factors on milk production and income over feed cost in eastern dairy herds
    Brown, Carl A. (Virginia Polytechnic Institute and State University, 1971)
    1380 Guernsey, 13614 Holstein, and 804 Jersey Dairy Herd Improvement yearly herd averages collected in eight Eastern and Southeastern states between 1965 and 1970 were analyzed to determine their value as management tools, identify recent trends in the dairy industry, and identify short term effects of changing herd size. Objective measures such as percent days in milk, milk production, and milk and grain price were found to be reliable estimates of true values. More subjective measures such as succulents, pasture and especially dry forage showed high coefficients of variation and appeared to be less reliable. Least Squares multiple regression techniques were employed to identify management variables which influence milk production and income over feed cost. Of nine measures analyzed, concentrate level, percent days in milk, other feed costs, and grain costs had the most significant affects on milk production. Twelve variables were found to significantly influence herd average income over feed cost in one or more of the three breeds studied. Curvilinear relationships were observed in many of the variables, but added little value to the final prediction equation. Differences between herd average variables for consecutive years were calculated, and when averaged, they represented yearly trends in dairying. Results for all three breeds were similar in magnitude with increases of 54 to 56 kgs. of milk per year, and 23 to 26 cents per cwt. per year in milk price. Using these differences, the affects of changing herd size were studied, and it was noted that as herd size increases rapidly, production per cow drops.
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    Cow Clipping is Important for Quality Milk Production
    Wagner, Philip E.; Jones, Gerald M.; Brown, Carl A. (Virginia Cooperative Extension Service, 1976-07)
    Clipping cows is one management practice which could stand more attention on many dairy farms. Many dairymen delay this chore until it is practically impossible to do a good job...
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    The effects of a dairy cow body condition scoring system on selected production and metabolic parameters
    Wildman, Edward E. (Virginia Polytechnic Institute and State University, 1979)
    A dairy cow body condition scoring system was devised by the author as a practical means of determining the body condition, or fitness pertaining to the degree of body fat of dairy cows at any point during the lactation cycle. The factors considered were the thoracic and lumbar regions of the vertebral column (chine, loin and rump), spinous processes (loin), anterior coccygeal vertebrae (tailhead), tuber sacrale (hooks), and tuber ishii (pin bones). All factors in the body condition scoring system must be considered while appraising each cow. Each cow was scored on a 1 to 5 scale with 1 indicating severe undercondition and 5 indicating severe overcondition. During an 18-month period, 28 cows in each of 29 Virginia dairy herds were used for obtaining body condition scores, body weight, frame size measurements and blood samples. Herds were chosen according to rolling herd milk production average and cows were chosen at random from within five Estimated Relative Producing Ability groupings to insure a representative sample of herds across and levels of production in Virginia and of cows within each herd. Herds were sampled at 3-month intervals and complete Dairy Herd Improvement Association records were obtained for each cow in each herd. The relationships of dairy cow body weight, frame size measurements, milk production and related parameters, and blood profiles to the body condition scoring system were determined. Body condition using this method was found to be independent of frame size and only moderately correlated with body weight, the number of intercostal spaces and the ratio of body weight to wither height. Body condition was found to be relatively low during early lactation and to increase through late lactation and remain constant during the dry period. Dairy cows of greatest milk production efficiency did not increase significantly in body condition throughout lactation, had fewer days open, but had less persistency of lactation. Dairy cows that increase significantly in body condition throughout lactation were less efficient milk producers, had a greater number of days open, had relatively high body condition scores in late lactation, but had greater persistency of lactation. Blood parameters, although statistically significant in many cases, were found to be of little or no practical value when compared between body condition, stage of lactation, and dairy merit groupings. The dairy cow body condition scoring system is a practical means of quantitating body condition of dairy cows.
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    Future Farmers of Virginia Chapter Chats January 1977
    Johnson, W. T.; Brown, Carl A.; Davis, Scot; Baugher, Carroll; Moore, Chris; Burgess, Melanie (The Future Farmers of Virginia, 1977-01)
  • Graze 300 VA
    Layton-Dudding, Jeannie; Mize, T. A.; Fike, John H.; Clark, R. A.; Brown, Carl A.; Swanson, Carrie A.; Fiske, David A.; Childs, Corey (2018-09-12)
    More than 50% of cow/calf production costs are found in winter feeding expenses in Virginia Extension budgets. To improve profitability while also improving water quality, beef cow/calf producers can reduce their reliance upon hay feeding by adding additional days of grazing during the winter dormant season. Graze 300 VA is an educational initiative designed to address this issue and its significant potential for economic impact. Presently, a small group of producers in Virginia’s Northern Piedmont and Northern Shenandoah Valley, regularly approach or achieve a 300-day grazing season. They extend their grazing season through adjustments in stocking rate and adjustments in pasture management. Having accomplished these needed changes, participants realize a 50% reduction in feed costs for each day of grazing added and a corresponding improvement in net revenue. The potential for additional net can be as high as $200 per calf sold when winter grazing is fully maximized. With over 96,000 beef cows in the Northern Shenandoah Valley and Northern Piedmont of Virginia, if 20% of the farmers (19,000 cows) improve economics by $100 per head per year, the benefit would be $1.9 million. Extending the grazing season will benefit water quality through improved water infiltration, improved nutrient use efficiency, fewer barren areas in fields from winter feeding sites, and improved soil organic matter. The Chesapeake Bay TMDL gives nutrient and sediment credit for every acre of pasture converted into a grazing management system and every foot of stream bank where livestock are excluded.