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 STORIES: Maryland Sheep & Wool 2005 Photos Raising Romneys in the UK (Winter 2001) Where Did Romneys Come From? (March 2001) |
PERFORMANCE
IMPROVEMENT FOR NORTH AMERICAN ROMNEYS THROUGH THE NATIONAL SHEEP
IMPROVEMENT PLAN by Stephen Shafer, Saugerties, NY Want to improve your flock without changing feed, schedules or labor? Do it through systematic genetic improvements guided by a Performance Recording System (PRS). Improvements in traits such as weight-for-age, maternal milking ability, fertility, yearling sheared fleece weight or average fiber diameter come far faster with a PRS than even the most astute breeder will get without one. ARBA members can now join an established PRS, the National Sheep Improvement Plan (NSIP). Seeing a project that can benefit every member, the ARBA Board resolved in August 2003 that all ARBA members should consider joining a PRS. The Board preferred NSIP to two other good PRSs, both based in New Zealand. As the designated Romney coordinator for NSIP I go further, to urge that all but our very smallest flocks join. (The smallest flocks are welcome, but would not themselves suffice.) Bringing Romneys into NSIP will help people who never show and circuit regulars alike. It will be a new incentive to “go Romney.” For statistical purposes, NSIP has to have a critical-mass breed group. Single flocks cannot join, as a diversity of flocks and a sufficiency of sheep are needed for valid comparisons across genetic lines. A breed needs at least 25 flocks recorded yearly for 2-3 years. Each flock needs at least 10 ewes lambing by each of three different sires. Flocks smaller than this, or shorter time intervals, will add information but would not be adequate. The more links there are among flocks (e.g. progeny of ram A now breeding on farms B, C, and D) the faster the possible progress. (The New Zealand PRSs, which do take single flocks, already have a big base of interlinked Romneys.) Relatively flocks can add information very well if genetic lines cross them. For example, a flock with 15 ewes enrolled in NSIP can add information if those 15 ewes are bred by a ram who the year before served another NSIP flock of the same size. Even using a son of that ram will contribute. Properly using a good-sized PRS to select breeding stock it should be possible to increase the average 60-day weights in your flock by 5-10 pounds over 5-7 years even if you don’t change other aspects of management. Comparable improvements in fertility and fleece weight are a realistic target also. While this may not seem a great commercial payoff for one small flock, recall what it means about vigor in that flock. Yet more important is that pulling mutually for measured improvement builds cooperation among breeders. A PRS serves the breed more than an individual. In fact, you don’t have to be a PRS to gain by its work, if you ask potential sellers to share findings. By getting data from many flocks and working those data hard NSIP (on a computer at Virginia Tech) can find which genetic lines offer the best chance of improving their progeny on the chosen heritable traits over a 5-10 year period. Most of us do at-home “performance recording” of a sort and try to make decisions with it, but we can’t adjust for all the variables. Nor can we factor in how our favorites’ progeny perform across a variety of programs and climes. NSIP does this and more, in terms of a statistic abbreviated EPD (for Expected Progeny Difference). EPDs and the related statistic “Expected Breeding Value” (EBV) are discussed clearly in NSIP publications on their website, www.nsip.org. Recent editions of the Sheep Production Handbook are also good on the methods. If you need hard copy, contact me at my address in Ramblings or at shpcount@earthlink.net. Put “NSIP” or “Romney” on the subject line. You as a participant will send me as coordinator data like lamb’s parentage, birth weight, early outcome etc. All the data points are familiar to you, though some are realized in a novel way. With 60-day weights, for example, you don’t try to weigh each lamb on its 60-day birthday. Instead, you weigh at one time a cohort whose ages bracket 60 days; you might weigh all February lambs on April 16, when the youngest is 47 days and the oldest is 75. You code for each lamb the early management he or she had (e.g. period of access to creep feed). I am asking as Romney coordinator that you record each sheep’s phenotype as W or B in the OPT (optional data) cell. NSIP wants to know every single outcome of every single breeding animal up to where the sheep leaves the farm. Omissions will cause more vagueness than bias, but either is bad. All your data and results are confidential. Only the best EPDs are made public. NSIP is not set up or able to decide who’s the “best” shepherd or who has the “best” flock. These constructs are not even looked at; they cannot be measured objectively, and NSIP is about objective measurements. It is a cooperative across-flock breed improvement effort. For Romneys in the US its use as a selling point comes second to its bigger purpose. A potential buyer, however, should ask person-to-person about EPDs for the selected traits just as she or he might about an on-farm statistic like 60-day weight. As the plan gets bigger with Romneys buyers will come to demand EPDs as a criterion in choosing breeding stock. NSIP ordinarily charges a breed $2000 a year for up to a thousand breeding animals, then $3000/yr for more than a thousand. The annual payment for each flock within the breed is structured differently by each breed to reach the total required, using the model of x dollars per flock plus y dollars per breeding sheep within that flock. NSIP offers new member breeds an introductory rate of $50/flock plus $1.25 per breeding animal (ram or ewe) recorded. Your flock annual fee is payable to NSIP when your annual report is in my hands. You will need scales for lambs and for sheared fleece weight. 60-day weights can be done on a bathroom scale. High-tech data like micron counts or loin eye scans are not required, though NSIP can already process the former. You’ll send me your data in NSIP’s spreadsheet format. I hope you can submit them electronically; NSIP has a customized Excel workbook I can send you. As breed coordinator I send in everyone’s data at one time, once a year. For 2004 submissions, that date is still undecided. It could be July 1 to include the 2003 lamb crop with, maybe, earlier observations from some breeders. Because of the once-a year plan, it is unlikely that information from lambs born in January of one year can be used for breeding decisions the next August. This may seem annoying, but it takes two or three years anyway to add precision to the estimates; particularly in the first year, don’t hold your breath. This is a slightly revised version of my article in the November 2003 Ramblings. Call, email or US mail me with your concerns and questions. Opinions are my own, not those of ARBA or NSIP; any errors are also my responsibility. Steve
Shafer Last updated 6/19/2005 All membership questions and Association business should be sent to the ARBA Secretary, Jean Kamenicky, at secretary@americanromney.org. This includes any comments on this web site or suggestions for content. Home | Romney
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