Sheep GEMS: Using Genotypes to Reduce OPP Susceptibility
In the United States, Ovine Progressive Pneumonia causes extensive welfare and financial losses due to decreased ewe productivity of about 20 percent and eventual culling or death of breeding stock. Surveys have shown that 36 percent of sheep operations have infected animals and 24 percent of all animals tested were seropositive. Once infected, sheep remain infected for life, and there is no effective treatment or vaccine.
Sheep producers can eradicate OPP from a flock in two ways. First, is by serological testing and removing all infected sheep with the obvious reduction in genetic diversity and reduced opportunity for making gains for other economically important traits. Second, is creation of a second separate negative flock by testing and isolating all young ewe lambs after weaning until serological testing at 9 months of age. As time goes on, the second flock ultimately replaces the infected flock, but with less impact on loss of genetic diversity or gains on other traits. While effective, these management procedures are time consuming, expensive and do little to improve sheep flocks in terms of genetic resistance to OPP. Thus, OPP-free flocks may continue to remain genetically predisposed to the virus causing OPP infection, with risk of re-infection if exposed to infected sheep.
Genetic variation within the ovine gene known as TMEM154 is associated with reduced susceptibility – although not complete resistance – to OPP infection. The testing for this relative susceptibility requires consideration of the entire protein rather than evaluating a single genetic marker. Those markers are more formally known as nucleotide polymorphisms (SNP). Variations at multiple SNP define the form of the TMEM154 gene expressed in each animal. The four most common versions of the TMEM154 protein – called haplotypes – in American sheep were designated 1 through 4 and represent 97 percent of the animals tested. The occurrence of one or two copies of either haplotype 2 or 3 is associated with increased susceptibility to OPP virus infection. Conversely, animals with combinations of haplotypes 1 and/or 4 have decreased susceptibility. In fact, such animals are nearly 10 times less likely to become infected with OPP than those carrying either haplotype 2 or 3. The haplotype 4 version – while favorably impacting susceptibility to OPP – results in a deletion of the TMEM154 protein. When homozygous, it results in animals with a complete knock-out and loss of function of the TMEM154 protein.
The genetic markers used to identify TMEM154 haplotypes are drawn from the genotyping platform used in Sheep GEMS. That entire platform has 50,000 SNP. The reliability of these TMEM154 haplotypes is being assessed in two ways. First, they were compared with known TMEM154 genotypes on a set of animals. They matched perfectly to previously recorded genotypes. Second, the SNP used to determine an animal’s genetic status for OPP susceptibility appear multiple times on the genotyping platform. When determining an animal’s TMEM154 haplotype, the consistency of those repeated SNP is checked. This second strategy resulted in 92.7 percent of the animals having genetic status determined and reported for TMEM154 for 15,586 sheep evaluated in the four breeds contributing to Sheep GEMS.
Genotypic status at TMEM154 differs substantially among Katahdin, Polypay, Rambouillet and Suffolk breeds. Nearly 60 percent of Katahdin and Suffolk sheep contained at least one of the highly susceptible alleles relative to OPP. On the other hand, in Polypay, only 8 percent, and in Rambouillet, 15 percent, were highly susceptible. It might be tempting to use the TMEM154 genotype as a primary selection criterion. However, we recommend a more balanced approach, where this information is incorporated into an existing breeding program. This allows breeders to continue to make genetic progress on their current priorities, while still reducing OPP genetic susceptibility in their flock.
One approach is favoring sires with the more favorable haplotypes of 1 and/or 4. Another is to avoid mating a ram and ewe that both carry an unfavorable 2 or 3 haplotype. If all other factors are equal, breeders should favor selection of haplotype 1 over haplotype 4, until more is known about the true function of TMEM154.
Acknowledgements. We thank U.S. sheep associations and breed organizations, the National Sheep Improvement Program and sheep producers, for their contributions to this research. This work is supported by the Organic Agriculture Research and Extension Initiative (grant no. 2016-51300-25723/project accession no. 1010329), and by the Agriculture and Food Research Initiative Competitive Grant (grant no. 2022-67015-36073/project accession no. 1027785), from the USDA National Institute of Food and Agriculture. Mention of a trade name, proprietary product, or specific agreement does not constitute a guarantee or warranty by the USDA and does not imply approval of the inclusion of other products that may be suitable. USDA is an equal opportunity provider and employer.
Source: Sheep GEMS
Australian Wool Market Continues Slide
The Australian wool market recorded an overall fall for the second consecutive selling series this week, hitting four-year lows.
From the opening lot of the first day of selling, it was apparent the market was in decline. Buyer activity was best described as cautious, with prices deteriorating as the sale progressed. By the end of the first day, the individual Micron Price Guides for Merino fleece had fallen by between 4 and 44 cents. Only the 17-micron MPG in the North defied the trend, posting a 13-cent increase.
Falls in the other sectors resulted in an 18-cent fall in the benchmark AWEX Eastern Market Indicator. It was the largest daily fall of the season and the largest since the Aug. 22, 2023. The EMI fell to 1,095 cents. This was the first time the EMI dropped below 1,100 cents since Oct. 13, 2020, when the EMI was trading at 1,066 cents.
The second day, only Melbourne and Sydney were in operation, where further falls were recorded, although less severe than the first day. The Merino fleece MPGs dropped by a further 1 to 36 cents with the largest fall in the 17-micron MPG in the North.
The EMI lost a further 8 cents. The EMI closed the week at 1,087 Australian cents, 26 cents lower. This was the largest weekly fall in the EMI since Week 8 of last season (Aug. 23, 2023). The drop in prices was met with seller resistance across all three centers, pushing the passed-in rate up to 11.9 percent.
Next week’s national offering is smaller, due in part to the lower prices on offer this week, discouraging some sellers. There are currently 33,830 bales on offer in Sydney, Melbourne and Fremantle.
Click Here for the ASI Conversion Table – AWEX Prices to USD Per Pound.
Source: AWEX
Update on NAHMS Sheep Study
Phase Two of the National Animal Health Monitoring Service Sheep 2024 Study will be wrapping up soon. Demands on field staff due to High Path Avian Influenza have resulted in a slight delay in finishing this phase and NAHMS staff are willing to continue working with interested operations to get everyone scheduled.
This phase includes biologic testing for GI parasites, scrapie genetic resistance and foot rot pathogens. If you have not been contacted and are interested in participating, please reach out as soon as possible to Dr. Natalie Urie at [email protected] or 970-888-4964.
Ohio State Will Conduct Fall Shearing School
Ohio State University’s Department of Animal Sciences and Extension will conduct a statewide sheep shearing school on Sept. 20-21 from 9 a.m. to 4 p.m. at the Dave Cable Farm in Hebron, Ohio.
During the two-day school, attendees will be given the opportunity to learn how to properly shear a sheep using the Australian shearing method. Those in attendance will be taught by veteran shearers as they walk through each step and demonstrate how to properly position the sheep and shearing handpiece in the correct location.
Attendees will also learn to appreciate fleece quality by ensuring that their workstation is clear of debris and how to keep the animal’s fleece all in one piece. This shearing session is open to all sheep producers, regardless of shearing experience.
Attendees will have the opportunity to try their hand at shearing using a variety of tools including electric handpieces, drop shaft units or an attendee’s personal equipment. Participants are encouraged to bring their own shearing equipment. Additionally, questions about comb and cutter placement, as well as maintenance will be discussed.
Please note that class space is limited to the first 16 participants with registration due by Sept. 13. The cost to attend is $100, which includes a boxed lunch for each day. For those interested in participating in this year’s school, please fill out the registration form. Additional information regarding this school and other sheep related events can be found on on the Events/Programs page.
Click Here for more information.
Source: OSU
Sheep Center Announces Request for Proposals
The National Sheep Industry Improvement Center Board of Directors is accepting grant proposals designed to improve the American sheep industry. Applications will be accepted through Sept. 30.
The center was re-established as part of the 2008 Farm Bill, at the request of the American Sheep Industry Association. As part of the 2019 Farm Bill, the center was awarded funding by USDA’s Agricultural Marketing Service to be used for the Sheep Production and Marketing Grant Program. Grant funding can be used on activities designed to strengthen and enhance the production and marketing of sheep and sheep products in the United States through infrastructure development, business development, production, resource development, and market and environmental research.
Currently, the center has budgeted approximately $300,000 for grants that will support projects consistent with the grant program. The average grant amount in the last four years has been approximately $30,000.
Click Here for additional information or contact NSIIC Program Manager Steve Lee at 207-236-6567 or [email protected].
Source: NSIIC
ALB Sponsors Flavor Experience in San Diego
Last week, the American Lamb Board sponsored the Flavor Experience event in San Diego. This annual three-day event brings together leaders in the food service industry to research trends and develop forward-thinking ideas related to delivering unique food experiences.
This year, approximately 500 food service operators, decision-makers, and chefs participated in the industry’s ultimate celebration of flavor. As a sponsor, ALB had the unique opportunity to showcase American lamb’s versatility and appeal.
For the event, ALB teamed up with Nicco Muratore – last year’s Seattle Lamb Jam winner – to present a unique brunch showcase. Unlike the usual fare at food events, ALB’s offering stood out with bold flavors and inventive presentations. Attendees loved the American lamb dishes prepared and served at the event.
“The event was a great opportunity to get in front of cutting-edge food service decision-makers looking for unique new recipes and flavors,” said ALB Chairman Jeff Ebert. “We were able to captivate attendees with two amazing dishes that showcased the versatility of American lamb.”
At the event, the team served Grilled Lamb Loin Lettuce Wraps featuring marinated and grilled lamb, charred eggplant salad, basil, mint and chili crisp, along with a Lamb Tostada topped with avocado labneh, guajillo braised lamb, Persian salsa macha, and pineapple-habanada pepper salsa. Both recipes were a hit among attendees.
The event was a fantastic platform for ALB to demonstrate the creativity that American lamb can bring to any menu. It sparked new menu ideas for attendees and developed new food service industry connections for the board.
For many years, ALB has prioritized reaching the food service industry with information about American lamb. Educational efforts that reach chefs and other food service professionals are a great way to introduce American lamb to more consumers. ALB will continue supporting restaurants committed to American lamb, including fine dining and fast-casual chains. In addition to events like this, ALB is able to reach food service audiences through partnerships with restaurants and suppliers, trade media outreach and educational tools.
Source: ALB
Rafter 7 Merino Sale Planned
The annual Rafter 7 Merino Ram and Ewe Sale is scheduled for Sept. 14 at the Eureka County Fairgrounds in Eureka, Nev. Sheep will be available for inspection beginning at 8 a.m. Lunch will be provided at noon and the sale will start at 1 p.m.
Rafter-7 Merinos is owned and managed by the University of Nevada-Reno and operating in Diamond Valley, Nev., at the Great Basin Research and Extension Center. The goal is to continue to provide high-quality rams for the sheep industry that are adapted to rangeland conditions.
Click Here to learn more.
Source: UNR/Rafter 7
Californians Offer Hands-On Ag Education
Pluth Homestead Ranch in Clearlake Oaks, Calif., is now home to Camp Kaos – a hands-on ranch school for both the ag-curious and established producers alike. The school teaches animal care and management skills that can only be learned by doing.
Jaime and Robert Irwin of Kaos Sheep Outfit, Maxine Lamperti of Pluth Homestead Ranch, Dr. Roselle C. Busch of the University of California-Davis, and University of California Cooperative Extension shearing instructor Stephany Wilkes have come together to create and share the agriculture education they’ve always wanted to have, in accessible formats: hands-on, one-day classes with English, Spanish and bilingual offerings.
A live lambing class is scheduled for Oct. 24 at the Pluth Homestead Ranch.
Click Here for more information.
Source: Camp Kaos
USDA Releases Updated Meat Label Guidelines
The U.S. Department of Agriculture announced this week the availability of an updated guideline that makes recommendations to strengthen the documentation that supports animal-raising or environment-related claims on meat or poultry product labeling. Today’s action builds on the significant work USDA has already undertaken to protect consumers from false and misleading labels and to implement President Biden’s Executive Order on Promoting Competition in the American economy.
Animal-raising claims, such as Raised Without Antibiotics, Grass-Fed, Free-Range, and environment-related claims, such as Raised using Regenerative Agriculture Practices and Climate-Friendly, are voluntary marketing claims that highlight certain aspects of how the source animals for meat and poultry products are raised or how the producer maintains or improves the land or otherwise implements environmentally sustainable practices. The documentation submitted by companies to support these claims is reviewed by USDA’s Food Safety and Inspection Service and the claims can only be included on the labels of meat and poultry products sold to consumers after they are approved by the agency. FSIS last updated its guideline on these claims in 2019.
In the updated guideline, FSIS strongly encourages the use of third-party certification to substantiate animal-raising or environment-related claims. Third-party certification of animal-raising or environment-related claims helps ensure that such claims are truthful and not misleading by having an independent organization verify that their standards are being met on the farm for the raising of animals and for environmental stewardship. The revised guideline also emphasizes more robust documentation for environment-related and animal-raising claims.
Additionally, the updated guideline recommends that establishments using negative antibiotic claims – such as Raised Without Antibiotics or No Antibiotics Ever – implement routine sampling and testing programs to detect antibiotic use in animals prior to slaughter or obtain third-party certification that includes testing. The revisions were informed by sampling data, petitions, public comments to those petitions and feedback received from a wide range of stakeholders.
USDA is committed to ongoing stakeholder engagement. For more information, please view the Federal Register notice. The updated guideline will be open for public comment for 60 days.
Click Here to read the full press release.
Source: USDA
Video of the Week
Get a first-hand look at the restored Nome (N.D.) Schoolhouse, which serves as a vibrant fiber arts retreat center, event space and boutique hotel.
The schoolhouse was built in 1916 and closed in 1970. It was purchased and restored by sheep producer Teresa Perleberg of Bear Creek Felting and Chris Armbrust of Dakota Fiber Mill.
Click Here to watch the video.