Browsing by Author "James, Robert E."
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- Adoptively transferred maternal colostral cells impact immune status and development in dairy calvesNeal, Stephanie Mary (Virginia Tech, 2013-09-25)Mortality and decreased weight gain resulting from infection and disease in dairy calves is a problem within the dairy industry. Colostrum is the sole source of maternal immunity for the calf, having a substantial impact on health and survival. To date, colostrum quality is determined by concentration of antibodies. Colostrum also contains proteins and cells, which may enhance immune development in the neonate. Our goals were to determine the impact of colostral immune cells on (1) immune status during the first month of life and (2) immune development over time. To determine the impact of adoptively transferred colostral immune cells, calves were fed either whole colostrum (WC) or cell-free colostrum (CFC) at birth. During the first month of life, calves fed CFC had decreased numbers of CD4+ T cells when compared to WC-fed calves. However, CFC-fed calves had a greater percentage of monocytes during the first month of life. To determine the influence of colostral immune cells on immune development, cellular blood parameters were measured in response to two series of vaccinations (A and B). After vaccination series A, CFC-fed calves had decreased numbers of B cells when compared to WC-fed calves. After vaccination series B, CFC-fed calves had decreased levels of interleukin-2 gene expression and numbers of CD4+ and gamma delta T cells when compared to WC-fed calves. This study demonstrates that colostral immune cells impact immune status and development in dairy calves.
- Competitiveness of Virginia dairy producers in a national setting given changing marketing and policy conditionsNubern, Chris (Virginia Tech, 1996)The objective of this study is to determine Virginia dairy producers’ competitiveness in an industry that is experiencing changing policy and marketing conditions. The competitiveness of Virginia dairy producers is examined in a National Dairy Model that compares both producers’ cost of production across market areas and spatial relationships among producers and consumers. The National Dairy Model (NDM) is a mathematical programming model that minimizes the total costs of producing milk and the assembly costs of shipping dairy products to the final consumer. A state's cost of production in the NDM is determined with a translog cost function. The cost functions are estimated with data collected in the 1989 and 1993 dairy versions of the Farm Costs and Returns Survey (FCRS). The supply and demand information in the NDM is annual data for 1994. Transportation costs are determined with current hauling rates and actual mileage between supply and demand points. Once the costs of production and spatial components of the NDM are formulated, the NDM is solved using the General Algebraic Modeling System (GAMS). The NDM is evaluated under the guidelines of several different scenarios. For example, some alternative marketing scenarios that provide important information about the future of the dairy industry are (1) simulations where the hauling rates are varied, (2) scenarios in which the U.S. becomes a major participant in the export market, and (3) situations where the marketing environment leads to increasing costs of production. Another alternative scenario involves only the spatial dimension of the NDM. Given the current marketing conditions in the dairy industry, the results of the NDM indicate that Virginia dairy producers are competitive in a marketing environment where the location of milk production is determined by a producer's costs of production and location advantages. Using Virginia's translog cost function, the cost per cwt. at the mean of the FCRS production data is $10.60. The cost estimate applies to Virginia's representative dairy farm where the average herd size is 91 cows and annual production per cow is 14,160 pounds. With these estimates and the fact that Virginia producers are near large population centers, the results of the NDM show that Virginia dairy farms are competitive in a deregulated market.
- Dairy Heifer Health, Disease Control, and VaccinationsBailey, Thomas L.; Murphy, Julia M.; James, Robert E. (Virginia Cooperative Extension, 2009-05-01)The future of the dairy herd is dependent on the production of superior heifers to replace culled lactating animals. It is imperative that the health status of the replacement animal is optimized.
- Dairy Pipeline, November-December 2018Overbay, Andy; James, Robert E. (Virginia Cooperative Extension, 2018-10-30)This issue has two articles. The first discusses being prepared for the impact of winter storms on farm animals, and focuses on generators, and on water pipes. The second discusses the importance of nutritional care of preweaned calves despite costs of milk and calf starter.
- Dairy Pipeline. April 2012Overbay, Andy; James, Robert E. (Virginia Cooperative Extension, 2012-04-01)Presents a case study of a dairy established by the Wallaces in Chilhowie and discusses consistency in calf feeding programs.
- Dairy Pipeline. April 2014James, Robert E.; Petersson-Wolfe, Christina S. (Virginia Cooperative Extension, 2014-03-26)Stresses the importance of cleaning colostrum containers for healthy calves, and discusses milk quality in Virginia.
- Dairy Pipeline. April 2015James, Robert E.; Petersson-Wolfe, Christina S.; Kanevsky-Mullarky, I.; Martel, Cynthia (Virginia Cooperative Extension, 2015-03-30)The articles in this issue of Dairy Pipeline include: The Truth about Staph. Aureus; Spring Cleaning!; and Dairy Pipeline, Activities.
- Dairy Pipeline. April 2016Martel, Cynthia; Ferreira, Gonzalo; James, Robert E. (Virginia Cooperative Extension, 2016-03-31)This issue contains two articles. The first article focuses on problems with mud and the health effects of muddy fields and lots on dairy cattle. The second article discusses the density of corn planting for silage production in terms of dry matter yield, and nutrition.
- Dairy Pipeline. January/February 2012James, Robert E. (Virginia Cooperative Extension, 2012-01-02)Discusses calf feeding during the winter months and introduces the recipient of the 2011 Bovine Practitioner of the Year award, Dr. Don Gardner.
- Dairy Pipeline. January/February 2013Welsh, John; James, Robert E. (Virginia Cooperative Extension, 2012-12-21)Discusses ethanol and the Renewable Fuel Standard, and milk replacers for calves.
- Dairy Pipeline. January/February 2015James, Robert E.; Winston, David R.; Daubert, Jeremy (Virginia Cooperative Extension, 2015-01-07)This issue of Dairy Pipeline includes articles on culling patterns, how to control nuisance birds, particularly the European Starling, and a list of upcoming activities.
- Dairy Pipeline. January/February 2016James, Robert E.; Gleason, Claire B.; Ferreira, Gonzalo; Spurlin, Kevin (Virginia Cooperative Extension, 2016-01-07)Articles in this issue provide details on feeding regimens for cattle, and on the quality of fats in milk.
- Dairy Pipeline. July/August 2010James, Robert E.; Welsh, John (Virginia Cooperative Extension, 2010-07-01)Discusses pros and cons of feeding milk replacers to calves and environmental compliance with EPA and DEQ guidelines.
- Dairy Pipeline. July/August 2011James, Robert E.; Callan, Peter L. (Virginia Cooperative Extension, 2011-07-30)Discusses small grain forages and maximizing pastures as a source of feed to offset rising grain prices.
- Dairy Pipeline. July/August 2012James, Robert E.; Welsh, John (Virginia Cooperative Extension, 2012-07-03)Discusses milk replacers and Shredlage, a new type of corn silage harvested with a modified chopper.
- Dairy Pipeline. July/August 2013James, Robert E.; Petersson-Wolfe, Christina S. (Virginia Cooperative Extension, 2013-07-01)Discusses negative impacts of hot weather on dairy cattle and maintaining bulk tank somatic cell count during hot summer months.
- Dairy Pipeline. July/August 2014James, Robert E. (Virginia Cooperative Extension, 2014-06-30)This issue deals with the questions of whether or not to feed calves waste milk and the importance of keeping detailed records of crops, cows, health, and production.
- Dairy Pipeline. July/August 2015James, Robert E.; Petersson-Wolfe, Christina S.; Cox, Beverly Gwen; Currin, John F. (Virginia Cooperative Extension, 2015-06-26)Discusses how to prevent mastitis in cattle, how to deal negative impacts of hot weather, and ways to improve cooling of milk.
- Dairy Pipeline. June 2012Winston, David R.; James, Robert E. (Virginia Cooperative Extension, 2012-05-30)Discusses using Twitter as a source of information and offers suggestions to offset economic conditions caused by high feed prices and low milk prices.
- Dairy Pipeline. June 2013James, Robert E.; Welsh, John (Virginia Cooperative Extension, 2013-06-05)Discusses facilitating the harvesting and storage of high quality forages and compares Maryland's environmental regulations to Virginia's.