With our most recent adventures into the heavy weather time of the year, I hope that everyone survived Hurricane Isabel with the least possible difficulties. Disasters like that can sure put a damper on things both in our personal lives and our social lives.
Well, the beginning of October has brought the start of out last training session for this calendar year. I am teaching the basic class this time with the help of Caryl Thompson, and Anita Ramsey is teaching an advanced class of "Teaching Through Games". I didn't participate (unfortunately) but the game of Tic Tac Toe last week did look interesting. I encourage all members to come out and join in.
Our board meeting from mid-September brought about the designation of the annual Nomination committee. The job of the nominating committee is to solicit members who would like to participate is officer/board positions for the club through the next year. Cristy Broyles is working on that at this time. If you get a call to participate on the committee or possibly for an office, consider giving of your time. The club will only be as good and the members in it and the time they can put towards its functions. Nominations will be formalized at the November board meeting and officer elections will be conducted at the December membership meeting (Christmas party). If you are interested or have questions on the process, please look through the club constitution and by-laws.
October is also a very big month for us as a years worth of planning and preparations will finally come to a culmination with the fall trial. At this point all trophy pledges should be gotten in and final working assignments will be made known. I highly encourage everyone to participate and help out with this event. You'll make all kinds of new friends, learn new things, and have an enjoyable time watching all the competitors do their best while in the ring. Just think, all that fun and it's not illegal, immoral, or explicit in any way!! I do hope to see you all there.
by David Hamel
October Trial: Your Presence is Requested!
Well, the trial is just around the corner: Saturday, October 25th & Sunday, October 26th. While
the entries have closed, it's not too late to volunteer. PCOTC
never turns down a volunteer! You can assist by stewarding (no experience required!), setting up or breaking down the equipment, or just filling in
as needed. For those who have not competed before, volunteering is a great way to learn about the sport,
to meet experienced handlers, and even meet various breeds. Of course, spectators are always welcome,
too! For more information, contact Maggie Hayes, trial chair, at
757-430-1552 or maggiejdog@aol.com
Managing Polygenic Disease: Hip Dysplasia as an Example
Polygenic disorders have been more difficult for breeders to manage. Examples are hip dysplasia,
congenital heart defects, and epilepsy. To manage them, they must be considered as threshold traits. A number
of genes must combine to cross a threshold producing an affected individual. If phenotypically
normal parents produce affected offspring, both should be considered to carry a genetic load that combined
to cause the disorder.
Hip dysplasia is a classic example of a polygenically controlled hereditary disease. Due to genetically controlled defects in anatomy and/or joint laxity, affected dogs can become lame, and eventually crippled due to secondary osteoarthritis. The genetic test used to manage hip dysplasia is the pelvic radiograph (x-ray). The Orthopedic Foundation for Animals (OFA) has a long-standing hip dysplasia registry to attempt to manage the disorder based on an extended-hip radiograph. OFA ratings are based on hip joint conformation (anatomy), joint laxity, and remodeling (arthritic changes). The Institute for Genetic Disease Control (GDC) also maintains a registry for hip dysplasia based on the extended leg view.
The PennHip method of evaluating hip status is based on a measurement of joint laxity different from that recorded on the extended leg radiograph. The PennHip method utilizes a radiograph taken while applying a uniform force on the hips of an anesthetized dog to measure the maximum distractibility of the hips. By computing a breed average of distractibility, and selecting for tighter hips than the breed average, it is believed that the incidence of hip dysplasia should decrease over time.
There are pros and cons to both the OFA and PennHip radiographic methods of managing hip dysplasia. The OFA radiograph documents anatomical abnormalities (shallow sockets, early bony changes), but only natural laxity in a hip extended view. The PennHip radiograph documents maximum distractibility, but many dogs with a high distraction index do not develop hip dysplasia. It is shown that both techniques have false positive and false negative results. For both methods, radiographic findings at an early age are highly correlated to dysplasia at a later age. OFA does not give permanent certification until two years of age, but offers preliminary evaluations at any age.
We know that the environment has a role in the expression of hip dysplasia. Overnutrition and excessive environmental trauma during the critical periods of ossification will promote later dysplastic development. While limiting these environmental stresses is prudent in pet dogs, it is recommended that breeders not overly protect or overly stress their dog's development. You do not want to mask the expression of dysplasia causing genes in breeding stock. Breeders should evaluate prospective breeding dogs raised under fairly uniform conditions, which neither promote, nor overly protect against hip dysplasia.
One reason we have not had great progress with managing hip dysplasia is that it is being treated as a single gene disease, with a test for carriers. In canine hip dysplasia, there is no excellent hip gene, although that is what most breeders are selecting for. In polygenic disorders, the phenotype of the individual does not directly represent its genotype. Breeders must break down affected phenotypes into traits that more directly represent the genes that control them. These include clinical signs of lameness (especially during the critical period of bony ossification between six and eighteen months of age), palpable laxity under anesthesia, deep acetabula, rounded femoral heads, the absence of remodeling, deeply seated hips on an extended leg view, and radiographic distractibility.
All dogs do not have hip dysplasia due to the same gene combinations. A dog with laxity and subluxation but normal anatomy, has hip dysplasia caused by different genes than a dog with no subluxation but malformed sockets. Selection against the components of the syndrome may provide better control. If a quality dog is to be bred, but has shallow hip sockets, it should be bred to a dog with deep hip sockets. Two dogs with fair hips can be bred together and produce much worse hips if they share detrimental traits, or could improve on each other if they compliment each other's good traits. You need to select for enough genes influencing normal development, to get above the threshold where dysplasia develops. Not all of these aspects will insure a genetically normal dog, but the chances increase with the more that are present.
Another reason for diminished progress against hip dysplasia and other polygenic disorders is that breeders have been selecting for generations of phenotypically normal parents and grandparents (depth of pedigree). In polygenic disorders the phenotype of the full brothers and sisters more directly represent the range of genes present in the breeding individual. In other words, the breadth of the pedigree is as important, if not more important than the depth of the pedigree in managing polygenic disease. Phenotypically normal dogs from litters with a high incidence of dysplasia are expected to pass on many genes that promote hip dysplasia. By selecting for breadth of phenotypically normal littermates of breeding dogs, and of parents of breeding dogs, all breeds should realize a decrease in hip dysplasia. In addition, the offspring of breeding dogs should be monitored to see which are passing the disorder with higher frequency
Many polygenic disorders have a major recessive or dominant trigger gene that must be present to produce an affected individual. The trigger gene in one breed or family may be different from the gene in others. Consequently, one test may not provide useful information for all breeds. Molecular genetic research to identify these genes can allow better control of polygenic disorders such as hip dysplasia, epilepsy, and cataracts in the future.
In summary, managing polygenically inherited disorders involves; 1) identifying traits that more closely represent genes being selected against, 2) the standardization of nuisance factors (such as environment) that can limit your selective pressure against the genes and 3) selecting for breadth of pedigree as well as depth of pedigree.
by Jerold S. Bell, DVM
Tufts University School of Veterinary Medicine, N. Grafton, MA, USA
A woman was visiting her blonde friend who had acquired two new dogs, and asked her what their names were. The blonde responded by saying that one was named Rolex and one was named Timex.
"Whoever heard of someone naming dogs like that?" said her friend.
"Hellooooo," answered the blonde, "they're watch dogs!"
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Just wanted to report that my GSP, The Flashman, finished his UKC Agility Champion Excellent title with 1st and 2nd placements at the UKC trials in Gloucester, VA on Sept. 6th. Submitted by Jackie Kirkman
Snap picked up two Started Retriever legs at the North American Hunting Retriever Assoc. field test hosted by the Northern Piedmont Retriever Club and held in Newville, PA on 9/27 and 9/28. The boy actually kept all four feet on the ground while heeling to the line. He must be growing up! Submitted by Maggie Hayes
Ada, along with her handlers - Chris and heather Dobzyniak- picked up her second junior hunter leg at the tidewater retriever club's fall test. She now has back to back successes!! we'll keep our fingers crossed for the next two tests ;-)
Snap hammered all five marks at the Shenandoah Valley HC field test in Weyer's Cave on 10/4. Only one more leg to go for his NAHRA title. Submitted by Maggie Hayes
Calla's Famis Magic Man "Malcolm" at 12 weeks of age had his first outing at a UKC Show in Charlotte NC in NLC Puppy Classes, Malcolm took back to back BEST IN MULTI BREED SHOW! Off to a good start! <Malcolm is a Niki son and is co-owned by Denise Call and Lisa Mann>. Submitted by Denise Call
<Editor's note: Now I expect lots of brags to be submitted by October
27th!>
The Portsmouth Chesapeake Obedience Training Club, Inc is a nonprofit organization composed of people who enjoy working and spending time with their dogs. We are interested in helping you train your dog to be a well mannered family member and a source of pride.
President: DavidHamel 757-478-6913 president@pcotcdogs.org
Vice President: Marie Stuart 757-465-5099 vpresident@pcotcdogs.org
Treasurer: Cathy Broyles 757-488-8752 treasurer@pcotcdogs.org
Corresponding Secretary: Cristy Broyles csecretary@pcotcdogs.org
Recording Secretary: Kendall Owens 252-771-3034 rsecretary@pcotcdogs.org
Board Members: Lovey Lyons 757-657-6564 board1@pcotcdogs.org
Denise Call 757-558-1120 board2@pcotcdogs.org
Mary Ann Maegher board3@pcotcdogs.org
Leslie Wemoff 757-465-0456 board4@pcotcdogs.org
We make every effort to distribute The PUP the first Wednesday of each month. In order to help us make this deadline, please submit information by the 25th of the previous month. Please send any submissions for The PUP to
Caryl Thompson 757-631-0712 pupeditor@pcotcdogs.org