2005 to 2008 Cornell Federal Formula Funds Research & Extension Project

Management of Sheep and Goats to Improve Animal Health and Farm Profitability - An Integrated Research and Extension Project

Current funding for the Cornell Sheep Program is provided by Federal Formula Funds through a project of Cornell University Cooperative Extension and the Cornell University Experiment Station.

Location

Cornell Teaching & Research Center Sheep Farm at Harford, New York, the Cornell University Ithaca Campus, the State University of New York College at Cobleskill and throughout New York

Leaders

• M. L. Thonney, Professor of Animal Science
• M. C. Smith, Associate Professor of Population Medicine and Diagnostic Sciences

Collaborators:

• Dr. Yung-Fu Chang (CVM) will make the leukotoxin-enriched bacterin using bacterial strains isolated from Cornell lambs.
• Dr. Belinda Thompson (CVM Ext. Vet.) will help to carry out the research and distribute results to veterinarians.
• Bernie Armata, Fay Benson, Julie Berry, Heather Birdsall, Jennifer Fimbel, Tom Gallagher, Bill Henning, and Joe Walsh (CCE Educators) will organize regional meetings and provide information in newsletters.
• Drs. Tatiana Stanton and Tro Bui (Animal Science Extension Associates) will provide information on goat management and marketing.
• Dr. Cynthia Shelley (SUNY Cobleskill) will provide data from the Cobleskill goat and sheep flocks and help to carry out extension programs and workshops.
• Brian Magee (Cornell Sheep Farm Manager) will help to carry out the experiments and give presentations at field days.
• Dr. Joe Regenstein, Professor of Food Science, will develop and deliver information about kosher/halal processing and ethnic marketing.

Justification

This project encompasses aspects of Federal Formula Funds priorities in 1) Agriculture and Food Systems (direct and niche marketing), 2) Community and Economic Vitality (land use), and 3) Natural Resources and Environment (sustainable systems). Sheep and goat pasture-based farming is one of the most environmentally-sustainable forms of agriculture for underused New York farmland. Since 1990 about 800,000 acres have gone out of farming in New York (NYAM, 2005; Ropel et al., 2000). Cropland pasture declined by 130,000 acres and permanent pasture declined by 120,000 acres during the same period. Much of this land is reverting to brush and forest with limited economic output and a reduction in pleasant open space. This vacant land could be used for grazing and for production of winter forage. Given the lucrative markets for lamb and goat meat in urban areas of New York and the Northeast, expansion of well-managed sheep and goat farms could use these vacant acres to provide significant family incomes and increase the economic activity of support industries in rural areas.

The integration of animal health and management research with Cornell Cooperative Extension programs will help to expand the number and size of sheep and goat farms in New York. The main experiment to be carried out under this project will develop and test an autogenous vaccine against pneumonia in sheep. This will address the one-fifth of national non-predator lamb losses due to pneumonia as reported in 2002 (NAHMS, 2002). As important as the lamb losses, are the unobserved effects on growth and carcass value; most pneumonia goes unnoticed until processing when observed lung damage prevents access to lucrative New York and Northeast kosher markets. Other possible causes of mortality in young lambs, such as level of colostrum intake and body condition of ewes, will also be monitored. This project needs to be done now to address pneumonia and other animal health and management issues that effect profitable expansion of commercial sheep and goat farming in New York, so that forage resources and marketing opportunities can be tapped that otherwise will be lost to better-supported New Zealand and Australian sheep and goat farmers.

An effective vaccine against lamb pneumonia has the potential to increase lambs sold per breeding ewe by 10% or more. Additional profitability is possible because lambs would have no lung damage, making them eligible for the kosher market. The annual economic impact of a 10% increase in lambs sold per ewe, using a conservative value of $80 per lamb, a 20% replacement rate, and a potential of 1.5 lambs weaned per ewe lambing, would be an additional $2,400 in a part-time flock with 200 lambings per year and an additional $12,000 in a full-time flock with 1,000 lambings per year. If kosher lambs are worth $10 more, then the marketing advantage for a flock with 200 lambings per year could be an additional $2,600. In a flock with 1,000 lambings per year the kosher market could provide an additional $13,000 annually. These specific examples are provided to show how an effective pneumonia vaccine could improve the profitability of individual farms, but the encouragement for expansion of sheep and goat farming and consequent improvement in the rural economies of many communities in New York could be even more important.

Background

According to the Census of Agriculture (USDA, 2002), the number of New York farms and animals, respectively, from 1997 to 2002 increased by 18 percent (to 2,207) and 21 percent (to 83,630) for sheep and by 50 percent (to 2,473) and 77 percent (to 33,130) for goats. Further expansion is likely due to higher consumer demand for sheep and goat products in the Northeast, and because increased efficiency of dairy farmers in the past 15 years has made available 800,000 acres of land. This project encompasses an intensive research and extension program to help sheep and goat farmers and potential farmers make the most profitable and ecologically sustainable decisions as they start or expand their flocks and herds.

Pneumonia is a major cause of lamb mortality and therefore, of lower profitability, in many sheep flocks. While overcrowding, poor ventilation, and inadequate bedding often are contributing factors, lamb pneumonia can be severe even in carefully managed flocks or in flocks kept only on pasture. For example, 80% of the lambs in some New Zealand flocks are infected (Goodwin et al., 2001) even though New Zealand lambs rarely see the inside of a barn. Additionally, while Bighorn Sheep live in well-ventilated environments, they are particularly susceptible to pneumonia (Cassirer et al., 2001).

Despite good ventilation in the barns at the Cornell sheep farm, since the start of 2000 about 7.25% of the 6159 lambs that lived longer than two days of age eventually died of pneumonia. Furthermore, lambs with clinical pneumonia require significant time for treatment, and the severity of pneumonia is directly related to reduced growth and feed efficiency (Alley, 1987; Jones et al., 1982).

One of the most lucrative markets for lamb and goat meat in the world is in New York City and other urban areas of New York and the Northeast with significant immigrant and ethnic populations. One of our goals is to help farmers use the large amount of vacant New York farmland to serve these markets. The kosher lamb market could be very important but many New York lambs do not qualify because, while never exhibiting clinical signs of pneumonia, their lungs have been damaged by pneumonia. For example, lungs in 27 of 34 Cornell lambs in a serial slaughter experiment from 77 to 161 days of age had evidence of pneumonia and only one of the lambs had been treated for pneumonia; it was 15 to 20 days of age at the time of treatment. The observation that lambs without clinical symptoms have lung damage from pneumonia at slaughter is not unusual; in New Zealand tens of thousands of lambs without clinical symptoms were found to have lung damage at slaughter (Goodwin et al., 2004). Thus, a vaccination program that could dramatically reduce or eliminate lamb pneumonia could have profound marketing, as well as production, advantages for New York farmers.

Vaccination of sheep against pneumonia has produced mixed results. Although there is evidence that the parainfluenza-3 (PI3) virus may cause the initial lung damage that enables bacterial pathogens to cause pneumonia, vaccination against PI3 has been only marginally effective (Cutlip et al., 1993; Davies et al., 1980; Davies et al., 1983; Lehmkuhl and Cutlip, 1985; Rodger, 1989; Thomas et al., 2002; Wells et al., 1978) and when a commercial vaccine against PI3 was tested in the Cornell flock, the results were inconclusive (Thonney et al., 2002). Commercial vaccines containing antigens for Mannheimia haemolytica and Pasteurella multocida, the two primary pathogens associated with pneumonia, also have not been very effective (Alley, 2002; Black et al., 1997; Black and Duganzich, 1995; Cassirer et al., 2001). An experimental vaccine against Pasteurella trehalosi and Mannheimia haemolytica had no effect on lamb survival in free-ranging or captive Bighorn Sheep (Cassirer et al., 2001). The commercial vaccine available for sheep in the United States is made from bovine organisms that are related, but not identical, to the bacteria that infect sheep.

The vaccination experiment included in this project will test a vaccine made from both the bacteria isolated from lambs that die of pneumonia in the Cornell flock and a toxin produced by the organisms that cause pneumonia.

Objectives

Profitability and sustainability of sheep and goat farming in New York will be improved by: 1) Developing a vaccine and management methods to reduce the incidence of pneumonia and other diseases that cause economic losses in flocks and herds; 2) Encouraging the use of management intensive and extended grazing; 3) Developing methods for small farms to use bulk purchases of locally produced feeds; 4) Developing and encouraging the use of recordkeeping software and economic spreadsheets to make better management decisions; and 5) Encouraging the development of marketing plans to take advantage of lucrative direct and niche marketing of sheep and goats.

Procedure

This integrated extension and research project will interweave results from testing management procedures and from a vaccination trial against pneumonia at the Cornell Sheep Farm with the results being delivered through field days, regional meetings, web delivery systems, popular press articles, and an annual sheep and goat symposium.

Efficient management of the Cornell T&R Sheep Farm, itself, is a research, teaching, and extension project to provide information for the expanding sheep and goat industries in the state. Based around a Cornell-developed accelerated lambing system (Lewis et al., 1996) with five lambing seasons a year, the farm is managed to provide sheep for teaching and for research on health management (vaccination against Johne’s Disease and control of lamb pneumonia), genetics (a DNA marker project for out-of season lambing and milk production), nutrition (defining optimum protein and fiber levels in complete mixed diets), pasture management, animal handling, and marketing strategies.

In addition to results from the pneumonia vaccination experiment, the benefits of management intensive and extended grazing systems at the Cornell Sheep Farm, and a data base system and spreadsheets already developed will be documented and demonstrated. Feeds formulated to use locally-available barley, corn, corn-gluten feed, and soy hulls will be tested and cost-effective methods of mixing and storing bulk feeds on small farms will be documented. Direct and niche marketing plans currently in use by sheep and goat farmers will be highlighted and encouraged through regional meetings. Research results and feeding and grazing systems will be demonstrated at the Cornell Sheep Farm during field days and at the annual Cornell Sheep and Goat Symposium, and be distributed via already-established web sites and a list server, CCE newsletters, the popular press and at regional meetings organized by CCE educators. Surveys of sheep and goat farmers will be used during and at the end of the project to assess awareness and usefulness of information developed and delivered by the project.

The main research thrust in this project is to develop and test the effectiveness of an autogenous vaccine to prevent pneumonia in young lambs (an approach also applicable to goats). The 600-ewe Cornell sheep flock, composed of Dorsets, Finnsheep, and crosses of these breeds, will be used in the project. The flock currently has a lamb pneumonia death loss ranging between 5 and 15% at each of the five lambing seasons. Ewes will be vaccinated prior to lambing so that the lambs receive antibodies via the colostrum (de la Rosa et al., 1997). Half the ewes will be vaccinated and half will be control animals. A subset of randomly-selected lambs will be vaccinated and compared with randomly-selected control lambs within each vaccinated and control ewe group for lambs born during the January and/or March lambing seasons.

Reproduction, health, weight, sales, and death data in the Cornell flock are recorded in the Cewe data base management system (Thonney, 2002). Symptoms and treatments are recorded each time an animal is treated for health problems. All dead animals are necropsied and diagnoses are recorded in the data base. Thus, the effect of vaccination on number of lamb treatments and deaths will be discerned from data in the Cewe data base. Survival analysis and binary logistic regression will be used to determine if vaccination affected treatments and deaths from pneumonia.

Because lamb pneumonia often goes undetected in live animals, 50 vaccinated (25 from each ewe group) and 50 control (25 from each ewe group) lambs assigned randomly at weaning from the January-born and/or March-born lambs will be slaughtered commercially at 30 to 50 kg live weight (100 lambs total) to score lungs for incidence of pneumonia and religiously unacceptable adhesions. A rabbi/shochet familiar with the requirements for lungs to pass kosher inspection will be recruited to teach those grading the lungs about what is required to meet requirements for the kosher market. Binary logistic regression will be used to determine if vaccination affected the incidence of lung damage from pneumonia and analysis of variance will be used to determine if the lung score for pneumonia was affected by vaccination.

Relevance, expected outcomes or impacts

Expected outcomes include increased number and vitality of offspring marketed per ewe or doe; reduced labor associated with health management; improved efficiency of pasture use and reduced reliance on preserved forage for winter feeding; increased use of locally grown feeds and available by-products in cheaper, better quality supplemental feeds; better economic decision-making through use of available software; and higher prices for market animals. These outcomes cut across applied research and extension priorities. Through potential exploitation of underused New York land by expansion of sustainable and profitable sheep and goat farming, these outcomes also encompass the CSREES National goals by 1) developing a farming system that is globally competitive; 2) providing culturally-relevant food; 3) increasing the number of food choices; 4) promoting environmental harmony with agriculture; and 5) enhancing the economies of rural families and communities.

Beneficiaries will be farmers who will have better methods to raise sheep and goats. But grain and hay farmers, banks, feed stores and other local community businesses will benefit from increased economic activity associated with expansion of sheep and goat farms. Consumers will benefit by being able to purchase fresh, high-quality, locally-produced meat that fits their food preferences.

Literature cited

Alley, M. R. 1987. The effect of chronic non-progressive pneumonia on weight gain of pasture fed lambs. N. Z. Vet. J. 35:163-166.

Alley, M. R. 2002. Pneumonia in sheep in New Zealand: an overview. N. Z. Vet. J. 50:99-101.

Black, H., W. Donachie, and D. Duganzich. 1997. An outbreak of Pasteurella multocida pneumonia in lambs during a field trial of a vaccine against Pasteurella haemolytica. N. Z. Vet. J. 45:58-62.

Black, H. and D. Duganzich. 1995. A field evaluation of two vaccines against ovine pneumonic pasteurellosis. N. Z. Vet. J. 43:60-63.

Cassirer, E. F., K. M. Rudolph, P. Fowler, V. L. Coggins, D. L. Hunter, and M. W. Miller. 2001. Evaluation of ewe vaccination as a tool for increasing bighorn lamb survival following pasteurellosis epizootics. J. Wildl. Dis. 37:49-57.

Cutlip, R. C., H. D. Lehmkuhl, and K. A. Brogden. 1993. Chronic effects of coinfection in lambs with parainfluenza-3 virus and Pasteurella haemolytica. Small Ruminant Research 11:171-178.

Davies, D. H., G. B. Davis, K. D. McSporran, and M. C. Price. 1983. Vaccination against ovine pneumonia:  a progress report. N. Z. Vet. J. 31:87-90.

Davies, D. H., A. R. McCarthy, and R. A. Penwarden. 1980. The effect of vaccination of lambs with live parainfluenza virus type 3 on pneumonia produced by parainfluenza virus type 3 and Pasteurella haemolytica. N. Z. Vet. J. 28:201-202.

de la Rosa, C., D. E. Hogue, and M. L. Thonney. 1997. Vaccination schedules to raise antibody concentrations against e-toxin of Clostridium perfringens in ewes and their triplet lambs. J. Anim. Sci. 75:2328-2334.

Goodwin, K. A., R. Jackson, C. Brown, P. R. Davies, R. S. Morris, and N. R. Perkins. 2004. Pneumonic lesions in lambs in New Zealand: patterns of prevalence and effects on production. N. Z. Vet. J. 52:175-179.

Goodwin, K. A., R. Jackson, C. Brown, P. R. Davies, R. S. Morris, and S. N. Perkins. 2001. Enzootic pneumonia of lambs in New Zealand: Patterns of prevalence and effects on production. Page 1 in Proceedings of the Society of Sheep and Beef Cattle Veterinarians of the New Zealand Veterinary Association.

Jones, G. E., A. C. Field, and J. S. Gilmour. 1982. Effects of experimental chronic pneumonia on body weight, feed intake and carcass composition. Vet. Rec. 110:168-173.

Lehmkuhl, H. D. and R. C. Cutlip. 1985. Protection from parainfluenza-3 virus and persistence of infectious bovine rhinotracheitis virus in sheep vaccinated with a modified live IBR-PI-3 vaccine. Can. J. Comp. Med. 49:58-62.

Lewis, R. M., D. R. Notter, D. E. Hogue, and B. H. Magee. 1996. Ewe fertility in the STAR accelerated lambing system. J. Anim. Sci. 74:1511-1522.

NAHMS. 2002. Sheep 2001: National animal health monitoring system Part I: Reference of sheep management in the United States, 2001. USDA:APHIS:VS:CEAH, Fort Collins.

NYAM. 2005. New York Agricultural Statistics Annual Bulletin. http://www.nass.usda. gov/ny/Bulletin/2005/05-bulletin. htm Online. Available: http://www.nass.usda.gov/ny/Bulletin/2005/05-bulletin.htm.

Rodger, J. L. 1989. Parainfluenza 3 vaccination of sheep. Vet. Rec. 125:453-456.

Ropel, S. C., B. L. Smith, C. L. Wagner, and B. S. Marx. 2000. New York Agricultural Statistics 1999 - 2000. Page 1 in  New York Agricultural Statistics Service, Albany, NY.

Thomas, D. L., Y. M. Berger, B. M. McKusick, and R. H. Stauffacher. 2002. The effect of IBR/PI3 and Pasteurella vaccination on the mortality rate of high percentage East Friesian lambs. Page 95 in D. L. Thomas, ed. University of Wisconsin, Madison, WI.

Thonney, M. L. 2002. Cewe data base management system. Web page Online. Available: http://www.sheep.cornell.edu/sheep/economics/cspsoftware/cewedoc/index.htm.

Thonney, M. L., M. C. Smith, and R. G. Mateescu. 2002. Vaccination of ewes and lambs against parainfluenza3 to prevent lamb pneumonia. Page 88 in D. L. Thomas, ed. University of Wisconsin, Madison, WI.

USDA. 2002. Census of Agriculture. http://www.nass.usda.gov/census/

Wells, P. W., J. M. Sharp, B. Rushton, N. J. L. Gilmour, and D. A. Thompson. 1978. The effect of vaccination with a parainfluenza type 3 virus on pneumonia resulting from infection with parainfluenza type 3 virus and Pasteurella haemolytica. J. Comp. Path. 88:253-259.