Changes in the Sheep Industry in the United States Making the Transition from Tradition (2008) / Chapter Skim
Currently Skimming:
Pages 121-168
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 121... ...
3 Sheep Health Issues M aintaining the health of a flock is imperative for a successful sheep operation because disease imposes both apparent as well as hid den costs on the operation. Obvious expenses include the price of treatments and death loss.
|
From page 122... ...
122 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES • Disease that results in wool loss or lower quality wool; and • Labor costs associated with treatment. Maintaining the health of the national flock has even broader implications than for any given individual flock.
|
From page 123... ...
SHEEP HEALTH ISSUES 123 • Technical resources; and • Availability of effective vaccines and treatments. Biosecurity and Replacement Practices Diseases gain entry into and spread within flocks by various routes.
|
From page 124... ...
124 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES with the producer about biosecurity practices, as well as a review of vaccination and testing programs, veterinary visits, and laboratory reports. Although quarantine is an effective way to monitor for and prevent disease introduction, only 33.9 percent of operations accounting for 16.4 percent of new additions administer any type of quarantine prior to commingling new animals with the existing flock.
|
From page 125... ...
SHEEP HEALTH ISSUES 125 Infectious Foot Rot Infectious foot rot can quickly become a chronic problem. It is difficult to eliminate, requiring time, labor, and financial resources.
|
From page 126... ...
126 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES the earliest sign being a loss of body condition, which is why this disease is sometimes called "thin ewe syndrome." Dyspnea develops later and may lead to exercise intolerance, causing a ewe to fall behind the rest of the flock. In some cases there is mammary gland or joint involvement.
|
From page 127... ...
SHEEP HEALTH ISSUES 127 Caseous Lymphadenitis (CL) Caseous lymphadenitis (CL)
|
From page 128... ...
128 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES Ram Epididymitis (RE) Ram epididymitis is more common in western range flocks and commonly introduced with the purchase or use of infected rams.
|
From page 129... ...
SHEEP HEALTH ISSUES 129 any serological or other evidence of disease, necropsy results, number of lambs at weaning, weaning weights, yearling weights, vaccinations given, treatments, cost of the treatment (including labor) , and number of animals culled and reason for culling.
|
From page 130... ...
130 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES fied to the flock of origin (flock in which an animal most recently resided for breeding)
|
From page 131... ...
SHEEP HEALTH ISSUES 131 extent, this is what happened in the cattle industry where identification was linked to the brucellosis program. As brucellosis was eliminated, identification and records were no longer available for managing other diseases.
|
From page 132... ...
132 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES premise identification number that corresponds to the contact information provided. The identification component provides the owner with a nationally unique identification for the animals on a registered premise.
|
From page 133... ...
SHEEP HEALTH ISSUES 133 Shearer (49.5) University/Extension (49.2)
|
From page 134... ...
134 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES lack of availability, lack of knowledge about sheep, cost, fewer disease and health issues, or something else? Would the increased use of veterinarians and veterinary services provide a benefit and added value or merely add a cost without adequate return?
|
From page 135... ...
SHEEP HEALTH ISSUES 135 ability Act (ADAA)
|
From page 136... ...
136 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES Stomach/Intestinal worms 62.1 Mastitis 42.7 Footrot 40.5 Vit. E/Selenium deficiency 35.7 Scours 34.9 Coccidiosis 31.7 Pregnancy disease (toxemia)
|
From page 137... ...
SHEEP HEALTH ISSUES 137 study, 74 percent of sheep operations reported the presence of stomach or intestinal worms in the previous three years (Figure 3-3)
|
From page 138... ...
138 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES sheep that have compromised immune systems from other diseases, from poor nutrition, or during lambing. Ewes usually experience a temporary relaxation of immunity slightly before and after lambing.
|
From page 139... ...
SHEEP HEALTH ISSUES 139 • Nicotinic anthelmintics -- this group includes levamisole, morantel, and pyrantel. Only levamisole is approved for sheep.
|
From page 140... ...
140 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES dewormer is required, it will be effective because the worms will be susceptible to treatment (Kaplan, 2004)
|
From page 141... ...
SHEEP HEALTH ISSUES 141 country. In the 2004 NAHMS study of mature sheep losses, old age was reported as the leading cause of death (26.8 percent of adult sheep death loss)
|
From page 142... ...
142 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES concern in the 1996 NAHMS study (USDA, 1996) , but it is the only sheep disease that has had a congressionally funded program aimed at control and/ or eradication since 1952.
|
From page 143... ...
SHEEP HEALTH ISSUES 143 er disease (GSS) , fatal familial insomnia (FFI)
|
From page 144... ...
144 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES Over the decades, there has been debate about the nature of scrapie and whether it is a genetic disease or is transmitted between sheep (Dickinson et al., 1974; Parry, 1983)
|
From page 145... ...
SHEEP HEALTH ISSUES 145 The properties of the causative agent are unusual because it is able to survive conditions that normally destroy other agents such as bacteria and viruses. The causative agent can survive conditions such as boiling, dry heat up to 600°C, formalin fixation, and treatments with many common disinfectants (WHO, 1999)
|
From page 146... ...
146 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES West Mountain Central East Percent Region FIGURE 3-4 Percent of that sheep tested positive for scrapie by region. Note: Because of the low number of samples obtained in the Western region, results for the Western region are included in the national estimates but are not listed individually.
|
From page 147... ...
SHEEP HEALTH ISSUES 147 can be done as a result of the identification requirements implemented in 2001. As infected or source flocks are identified, government veterinarians work with producers to develop a plan to remove animals determined to be most susceptible.
|
From page 148... ...
148 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES to be 100 million dollars (USDA, 2000)
|
From page 149... ...
SHEEP HEALTH ISSUES 149 cant. This conclusion is reflected in the 1996 NAHMS survey, which found that scrapie was not among the top 15 diseases of concern (USDA, 1996)
|
From page 150... ...
150 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES lamb MBM or the export of pet food to other countries. The actual value of the lost trade is not known and may not be significant.
|
From page 151... ...
SHEEP HEALTH ISSUES 151 the first cases of nonclassical scrapie in 2003. They called this Nor 98 scrapie (Benestad et al., 2003)
|
From page 152... ...
152 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES for ARR animals. These programs were initiated when it was thought that arginine (R)
|
From page 153... ...
SHEEP HEALTH ISSUES 153 THREAT OF EMERGING OR EXISTING DISEASES Threat from an Existing Disease In the past decade, over 70 percent of the emerging diseases have been zoonotic (Woolhouse and Gowtage-Sequeria, 2005)
|
From page 154... ...
154 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES surveys have indicated that the primary problem is in the dairy cattle sector but it is also increasing in the nation's beef cattle herd. If there were ever a definitive link made between Johne's and Crohn's or if the public perceived there was a risk, a number of food safety questions would need to be answered: • Given that the Johne's agent is shed in large numbers (millions of organisms)
|
From page 155... ...
SHEEP HEALTH ISSUES 155 Threat from a Foreign Animal Disease The findings of the NAHMS 2001 sheep study (USDA, 2003a) indicate that certain behaviors and lack of certain practices increase the vulnerability of many sheep operations to disease.
|
From page 156... ...
156 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES MAJOR ACCOMPLISHMENTS, OPPORTUNITIES, AND CHALLENGES IN SHEEP HEALTH Disease adversely impacts viability, overall growth, rate of gain, immunity, and reproductive performance, which in turn reduce income. Flock health programs should be an essential component of the overall management scheme of raising sheep.
|
From page 157... ...
SHEEP HEALTH ISSUES 157 portunity for growth unhampered by factors that may negatively influence public opinion and purchases. Other opportunities include: • Use of the identification system for animal movement as the foundation for an overall flock health program.
|
From page 158... ...
158 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES have not raised livestock before. The lack of practitioners to give advice, administer treatments, perform surgeries, and euthanize animals may lead to prolonged and unnecessary suffering.
|
From page 159... ...
SHEEP HEALTH ISSUES 159 Andréoletti, O., S Simon, C
|
From page 160... ...
160 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES González, L., M Jeffrey, S
|
From page 161... ...
SHEEP HEALTH ISSUES 161 Millar, D., J
|
From page 162... ...
162 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES Seidel, B., A Thomzig, A
|
From page 164... ...
164 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES APPENDIX: A Chronology of Scrapie Control in the United States 1947 – First case of scrapie was diagnosed in a Michigan flock. The sheep were of British origin imported from Canada over a period of years.
|
From page 165... ...
SHEEP HEALTH ISSUES 165 1975 – Bloodline option was eliminated. Exposed animals could no longer be slaughtered for human consumption due to a perceived public health risk.
|
From page 166... ...
166 CHANGES IN THE SHEEP INDUSTRY IN THE UNITED STATES The following organizations were represented on the Rulemaking Committee: American Association of Small Ruminant Practitioners American Farm Bureau American Hampshire Association American Meat Institute American Polypay Association American Sheep Industry, Inc. American Suffolk Society Animal and Plant Health Inspection Service Continental Dorset Club National Assembly of Chief Livestock Health Officials National Renderers Association National Suffolk Association United States Animal Health Association 1991 – The Rulemaking Committee agreed upon a core program for the control of scrapie.
|
From page 167... ...
SHEEP HEALTH ISSUES 167 Federal regulations that enacted the NSEP went into effect: (1) Records and identification required for sheep moving in interstate commerce, (2)
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.