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                                                     Vet Topics                                                                                       winter 2006




StriVinG to improVe the
                                                                Dental Debut
QualitY of health care for                       Pick an animal, any animal, and chances are that one               “When we diagnosed and treated animals’ dental
Your BEST FRIENDS.                        of its kind has shown its teeth to Dr. James Anthony. During his    problems, the pain went away. Those results really convinced
                                          23-year career, the veterinary dentist has peered into the mouths   us that we were overlooking a serious issue — and now, the
                                          of everything from Chihuahuas, Persians and Quarter horses to       public and practitioners are demanding more expertise in
                                          vampire bats, lions, hippopotamuses and killer whales.              veterinary dentistry.”
Vet Topics is published by the western           Variety is a hallmark of veterinary dentistry, but for             In response to that demand, WCVM hired Anthony
college of Veterinary medicine’s          Anthony, the specialty’s main attraction is understanding how to    to establish a veterinary dental practice at its teaching
companion animal health fund.             ease an animal’s oral pain: “Veterinary dentistry was overlooked    hospital and to enrich undergraduate veterinary students’
Visit www.cahf.usask.ca.                  until we realized that dental problems cause a lot of pain          dentistry training. “The hope is that WCVM graduates will
please send comments to:                  and discomfort for animals,” explains the specialist. Anthony       have a greater knowledge of dentistry and be aware of other
dr. John pharr, editor, Vet Topics        operated general and referral practices in Vancouver, B.C., for     treatment options besides extracting a tooth,” says the dental
wcVm, university of Saskatchewan          more than two decades before joining WCVM’s Department of           specialist. “As a result, they can offer a higher level of care to
52 campus drive
                                          Small Animal Clinical Sciences in January 2006.                     their patients once they’re in practice.”
Saskatoon, SK S7n 5B4
t: 306-966-7060 f: 306-966-7174                  Veterinarians have always been trained to diagnose                 Anthony began offering referral and clinical services
john.pharr@usask.ca                       common dental problems and perform common procedures                to western Canadian veterinarians and pet owners at WCVM
                                          such as tooth extractions. Veterinary dental specialists can        in mid-February. Because an increasing number of pets
editor: dr. John pharr                    offer advanced services like tooth implants, periodontal            reach old age, periodontal disease is a common problem
managing editor: myrna macdonald          (gum) disease treatments, orthodontic procedures and                                                                   continued . . .
For article reprint information, please   root canals (endodontics) — Anthony’s favourite area of             aBoVe: Veterinary dentist Dr. James Anthony performs a tooth
contact sm.ridley@sasktel.net.            dentistry.                                                          extraction while fourth-year student Cathy Dick monitors the
                                                                                                              anesthetized canine patient.
                                                                            dental deBut continued
                                                                            seen in feline and canine patients. As well, certain breeds have developed genetic
                                                                            malocclusions (misalignment of upper and lower teeth) or other dental issues that
                                                                            require specialized care.
                                                                                   While cats and dogs are his main focus, Anthony also provides consulting services
                                                                            for large animals and exotic pets at the teaching hospital. “A diverse caseload is a key
                                                                            part of this new program — and that’s why I encourage veterinarians across Western
                                                                            Canada to send referral patients here so we can develop veterinary dentistry training to
                                                                            its fullest.”
                                                                                   Anthony’s curiosity about veterinary dentistry grew soon after he graduated from
                                                                            WCVM in 1983 and joined a general practice. After reading the few published words
                                                                            about veterinary dentistry, he collected as much information as he could from his
                                                                            dental hygienist and dentist, then learned how to adapt human dentistry principles to
                                                                            animals by visiting (human dentistry) specialty practices.
                                                                                   Anthony eventually joined other self-taught specialists to organize the first specialty
                                                                            group and diplomate program for veterinary dentists. Today, 88 specialists (including
                                                                            eight Canadians) are certified by the American Veterinary Dental College (AVDC).
                                                                                   By introducing this specialty to its undergraduate students, WCVM also hopes
                                                                            that some graduates may pursue a dental residency once Anthony builds a dentistry
                                                                            caseload at the College’s Veterinary Teaching Hospital. The specialist also plans to
                                                                            develop a research program that targets issues in companion animal dentistry and in
                                                                            occupational safety.
                                                                                   For more information about WCVM’s veterinary dentistry program, contact
                                                                            Dr. Anthony (306-966-8606 or james.anthony@usask.ca). V



                                                                                  PET PROJECTS
                                                                                      Highlights of published companion animal research
                                                                                                 conducted by WCVM scientists.
                                                                            focus on feline corneal Sequestra
                                                                                   Domestic cats can develop corneal sequestra — oval or round pieces of dark
                                                                            brown or black plaque that extend deep into the corneal tissue. Although no one knows
COLLEGE CONSTRUCTION: mild weather has allowed crews to make                what causes these painful pieces of dead corneal tissue to form in cats’ eyes, their
steady progress on wcVm’s expansion — a series of projects that             development is often associated with corneal trauma, dry eye syndrome, abnormal
will deliver more specialized services, new technologies and a higher       eyelid conformation or feline herpes virus infection. Persian, Siamese, Burmese and
level of health care to companion animals. TOP: By late January, the        Himalayan cat breeds are predisposed to developing corneal sequestra, so genetics and
Veterinary teaching hospital’s two-storey addition (east side) was
                                                                            conformation may also be involved in the disease.
covered in insulated tarps so workers could continue pouring cement
in colder weather. work on the addition is about 15 per cent complete,             Last year, Drs. Bruce Grahn, Steve Sisler and Eric Storey published the results
while foundation work is at the halfway mark. the hospital’s enlarged       of a qualitative evaluation of tear film (the liquid layer bathing the cornea and
and renovated Small animal clinic will have more examination rooms,         conjunctiva) and an assessment of conjunctival goblet cell numbers in cats with and
additional space for specialized services, an expanded closed surgery       without corneal sequestra. Goblet cells are mucous-secreting, cup-shaped cells in the
area, a larger treatment room and more space for pets and their             conjunctiva — the thin, clear, moist membrane that coats the inner surfaces of the
owners during their stay at the hospital. BOTTOM: the new research          eyelids and the outer surface of the eye.
wing (south side) has quickly taken shape since construction began in              During the study, the researchers conducted a number of ophthalmic
october 2005. crews began pouring concrete at the research wing site        examinations and molecular testing on 11 cats with corneal sequestra and 14 eyes
in february. the new structure will be a central area where scientists      of cats with no signs of ocular disease. As well, the scientists collected biopsies of the
throughout wcVm can access a range of technological and human
                                                                            palpebral conjunctiva (which covers the posterior surface of the eyelids) at different
resources for research in areas such as assisted reproduction and genetic
disease investigations in companion animals. Visit www.wcvm.com for         regions for statistical comparisons of goblet cell numbers.
more construction updates.                                                         Based on test results, the scientists concluded that the development of corneal
                                                                            sequestra doesn’t appear to be linked primarily to abnormal goblet cell numbers,
Help us to expand health care for companion animals in Western              qualitative tear film abnormalities and accelerated tear film break-up time. The
Canada. Make a donation to the Veterinary Teaching Hospital                 research team detected no neurologic abnormalities in any of the cats. Schirmer tear
Expansion Campaign by:                                                      tests (dry eye tests) and intraocular pressures were within normal reference ranges. No
• using the enclosed tear out card                                          abnormalities were noted on indirect ophthalmoscopic examinations. As well, scientists
• visiting www.wcvm.com/supportus                                           found no significant differences in tear film break-up times and goblet cell numbers in
• contacting Joanne Wurmlinger, WCVM development officer, at
                                                                            eyes with or without corneal sequestra.
306-966-7450 (joanne.wurmlinger@usask.ca).
                                                                                   Grahn BH, Sisler S, Storey E. “Qualitative tear film and conjunctival goblet
                                                                            cell assessment of cats with corneal sequestra.” Veterinary Ophthalmology.
                                                                            2005; 8(3): 167-170. V
                                                                                                                                                                             2
    CanCER CaRE KiT                                                                             abnormal characteristics in soft tissues such as a patient’s brain. WCVM
                                                                                                specialists also use MRI scans to plan surgical and radiation treatments.
                                                                                                • nuclear scintigraphy: Part of WCVM’s expansion plans, nuclear
                                                                                                scintigraphy will allow the College’s specialists to detect and diagnose
                                                                                                malignant abnormalities so clinicians can develop an appropriate therapy
                                                                                                plan. Specialists use this technology to pinpoint “hot spots” of increased
                                                                                                metabolic activity in a patient’s body.
                                                                                                diaGnoStic patholoGY
                                                                                                Clinical and anatomic pathologists at WCVM and at Prairie Diagnostic
                                                                                                Services (PDS) — the provincial diagnostic laboratory based at the
                                                                                                College — serve an important role in the diagnosis, prognosis and
                                                                                                management of cancer patients.
                                                                                                • hematology (examination of blood), biochemical profile and
                                                                                                urinalysis: Blood tests are vital to confirming a diagnosis of certain types of
                                                                                                cancer, in differentiating some types of malignancy (such as leukemia) and
                                                                                                in detecting secondary infections and other consequences of cancer. Multiple
                                                                                                blood tests also enable clinicians to monitor the effects of oncology therapies
                                                                                                on a patient’s overall health.
                                                                                                • cytology (examination of cells): A microscopic examination of cells
                                                                                                taken from a skin lump, an enlarged organ or a body cavity can help clinical
                                                                                                pathologists confirm whether malignant cells are apparent. In some cases, it
                                                                                                also allows them to determine the type of tumour in tissue or fluid samples.
                                                                                                • histology (examination of tissue): WCVM surgical specialists perform
                                                                                                surgery, use biopsy needles or endoscopic tools to remove biopsies (pieces of
                                                                                                solid tissue from a lump or affected organ). Then, pathologists trained in
                                                                                                histopathology (microscopic study of diseased tissue) can examine slices of
                                                                                                tissues to diagnose specific types of cancer and determine a malignancy grade.
    cancer isn’t limited to humans: according to the american                                   WCVM and PDS pathologists also use immunohistochemistry techniques (the
                                                                                                process where antibodies are used to stain targeted proteins) to detect proteins
    Veterinary medical association, the disease accounts for                                    that may be characteristic of a particular tumour type under the microscope.
    almost half of the deaths of pets over 10 years of age.
                                                                                                oncoloGY therapY
    Since most small animal veterinarians diagnose and treat
                                                                                                • chemotherapy: Clinicians often use anti-cancer drugs to treat certain
    cancer on a daily basis, wcVm has developed a base of                                       types of cancer, or they may combine chemotherapy with surgery or radiation
    technologies, expertise and services that can be used for                                   therapy for a pet. Ultimately, the aim of using chemotherapy is to extend a
    teaching veterinary students in all aspects of oncology.                                    pet’s life while maintaining its quality of life versus the goal of curing the
                                                                                                patient. As a result, chemotherapy protocols for pets are less aggressive than
                                                                                                ones used in human medicine and often have fewer side effects.
          But besides training, all of these diagnostic and therapeutic resources are           • Surgery: Surgical specialists play a major role in diagnosing and treating
    available to referring veterinarians and pet owners across Western Canada. Scientists       cancer in pets at WCVM. Members of the surgical team perform biopsies,
    at the University of Saskatchewan also use these assets to develop new methods of           surgically remove malignant tumours and perform reconstructive surgery to
    detecting and treating the disease in companion animals and in humans. Here’s an            repair large wounds caused by tumour removal. When appropriate, surgical
    overview of what’s available at WCVM:                                                       specialists also perform palliative surgery to improve a pet’s remaining quality
    medical imaGinG                                                                             of life and gain additional time.
    • radiography: Medical imaging specialists use radiographs (X-rays) to detect               • radiation oncology: Dr. Monique Mayer, a veterinary radiation oncologist,
    any deformities or abnormalities in a patient’s bones or in some organs. By taking          initiated WCVM’s pet radiation therapy program in 2004 when the College’s
    multiple radiographs over time, clinicians can also monitor the growth of a tumour          cobalt radiation unit began operating. Radiation can be used as a curative
    or detect metastasis (spreading of a primary tumour to other organs or parts of the         therapy for a certain group of cancerous tumours, or palliative radiation
    body) in a patient.                                                                         can take away patients’ pain and improve quality of life. In other cases, a
    • ultrasonography: Ultrasound technology can detect small, abnormal growths                 pet may receive a combination of therapies including radiation, surgery
    in soft tissue or in organs. Surgical specialists also rely on ultrasound to successfully   and chemotherapy. Specialists also use radiation to help shrink a cancerous
    perform fine needle aspirates and biopsies that target abnormal cells within healthy        tumour before surgery, or they may use it after a tumour is surgically removed
    tissue.                                                                                     to destroy any diseased cells that may have been left behind.
    • computed tomography: WCVM’s new CT scanner can detect potential tumours                   • medical oncology: The search is on to add a board-certified, veterinary
    in a patient’s thoracic spine, lungs or nasal cavity. The device also supplies WCVM’s       medical oncologist to WCVM’s specialist team. This new team member
    cobalt radiation machine with scans showing a tumour’s size, shape and location.            will have specialized knowledge in diagnosing cancer, staging tumours
    • magnetic resonance imaging: This technology’s sensitivity and its finely                  (determining the degree of malignancy), developing treatment plans and
    detailed, cross-sectional images make it the premier imaging tool for detecting             using chemotherapy. V


3
                                                                                       the technology used to remove cataracts has changed over time, but
                                                                                 the disease’s main causes remain the same. most canine cataracts are
                                                                                 inherited and typically occur in young to middle-aged purebred dogs.
      Blindness used to be imminent for many dogs diagnosed with cataracts,      another common cause is diabetes mellitus: up to 75 per cent of diabetic
but in the four decades since cataract surgery became available for canine       dogs develop cataracts within one year of their diagnosis. cataracts also
patients, the prognosis has become much brighter.                                develop in the eyes of older dogs, but it may take many months to several
      the main reason behind this improvement is the use of phaco-               years before the cataracts are large enough to cause vision loss.
emulsification, a surgical technique that relies on ultrasonography to remove          wcVm’s two veterinary ophthalmologists, drs. lynne Sandmeyer
cataracts. in the past decade, this new technology has boosted the success       and Bruce Grahn, use the college’s operating microscope to perform
rate for cataract surgery from 35 per cent to a rate ranging from 85 to 95 per   phacoemulsification, as a first step, the specialists access the lens by making
cent.                                                                            an incision in the cornea, then tearing a round hole in the front of the lens
      a cataract is any opacity in the eye’s normally clear, disc-shaped         capsule. next, they insert a pen-like instrument through the lens capsule
lens. the lens allows light to enter the eye and helps to focus that light on    hole. inside, the device produces ultrasonic vibrations that break up the
the retina, but when the highly organized cells that make up the lens are        lens fibres — simultaneously vacuuming up the broken up material and
damaged, any size or shape of cataract can develop. while smaller cataracts      removing it from the eye.
may not significantly interfere with a dog’s vision, larger ones can obstruct          once all of the lens fibres are removed, the ophthalmologists may
light from entering the eye and eventually cause blindness.                      implant a lens into the lens capsule — an option that significantly improves

                                                                                                                                                               4
near sightedness but isn’t necessary for restoring vision. finally, the specialists
close up the cornea with tiny sutures that are eventually absorbed by the eye
within a month.
      while the surgery’s success rate is high, complications like uveitis
(inflammation inside the eye) can develop after surgery. other possible
problems include corneal ulcers, temporary increases in intraocular pressure,
glaucoma or retinal detachments.
      post-operative care plays a large part in achieving a positive outcome          precedinG paGe (top left): the surgical team prepares the anesthetized
and avoiding some of these potential problems. for example, patients’                 patient for cataract surgery. Bottom left: after the eye is bathed with dilute
                                                                                      Betadine® (antiseptic) and prepared for surgery, dr. lynne Sandmeyer cuts a
activities must be severely restricted for at least four weeks and protective
                                                                                      hole in the blue draping. Bottom right: Some of the tools involved in cataract
collars must be worn to prevent self-mutilation and accidental trauma to their        surgery. top right: Sandmeyer prepares the dog’s eye for phacoemulsification,
eyes. during the first month, owners must also insert different types of drops        a surgical technique that uses ultrasonography to remove lens fibres. thiS
in their dogs’ eyes several times a day. while dosing frequency goes down             paGe (top left): a close up view of the pen-like instrument that produces
over time, some dogs require anti-inflammatory eye drops for the rest of their        ultrasonic vibrations and break up the lens fibres. Bottom left: this
lives.                                                                                microscopic view shows the dog’s pupil (the blue circle) partially covered by
      for more information about cataract surgery and wcVm’s veterinary               viscoelastic material (the liquid globule) that prevents drying during surgery.
ophthalmology services, visit http://www.usask.ca/wcvm/vth/sac/ophtho/                top right: Sandmeyer concentrates on her work through the lens of the
about.php                                                                             operating microscope. Bottom right: cataract surgery requires a roomful of
                                                                                      specialized tools and a highly-trained surgical team. Photos: Michael Raine
5
  B lO C K i n g
T h E PaT h O f
CanCer
Angiogenesis — the formation of new blood vessels — is a vital part of
wound healing and embryo development in human beings and animals.
But this natural process also has a dark side that was first described by
a Boston surgeon, dr. Judah folkman, in 1971. folkman’s controversial
theory, published in the New England Journal of Medicine, hypothesized
that the growth and metastasis of cancerous tumours is dependent on
angiogenesis. folkman’s peers initially ridiculed his ideas, but 30 years
later, developing ways to inhibit blood vessel formation in cancerous
tumours is an important goal for many human and veterinary scientists
around the world — including a research team at the western college of
Veterinary medicine (wcVm).

       When Dr. Ahmad Al-Dissi describes his angiogenesis research, it isn’t long
before the name Avastin™ pops up in the graduate student’s conversation. For
Al-Dissi, this anti-angiogenesis drug represents the future in oncology therapy for
humans as well as for companion animals. Avastin™ (or bevacizumab) became
commercially available to human cancer patients in 2005 and was effective for
treating colorectal cancer in clinical trials — especially when the drug treatment
was combined with conventional chemotherapy.
       Can anti-angiogenesis drugs like Avastin™ be effective in treating certain
types of cancer in dogs? “More research needs to be done, and it may be that we
would need to produce our own version of the drug,” acknowledges Al-Dissi. “But              Dr. Ahmad Al-Dissi graduated first in his class when he received his
it’s very possible that Avastin™ could eventually be used to reduce the growth of            doctor of Veterinary medicine (dVm) degree from Jordan university
certain tumours in dogs.”                                                                    of Science and technology in 2002. after working one year as a large
       What intrigues Al-Dissi is the new drug’s target: the monoclonal antibody             animal clinical associate at the institution, al-dissi began a three-
seeks out and inhibits the binding of vascular endothelial growth factor (VEGF)              year master of Science program in wcVm’s department of Veterinary
to its receptor, VEGFR. These two proteins play crucial roles in the formation               pathology.
of new blood vessels in healing wounds, developing embryos and malignant                           his graduate studies have sparked a keen interest in
tumours.                                                                                     angiogenesis, and once al-dissi completes his master’s degree this
       That’s where Al-Dissi and his graduate studies supervisor, Dr. Beverly Kidney         summer, he hopes to find work related to the development of anti-
of WCVM’s Department of Veterinary Pathology, become part of the research                    angiogenesis drugs for use in companion animals or humans. later
puzzle. With financial support from WCVM’s Companion Animal Health Fund last                 this year, al-dissi and Kidney will submit their research findings about
year, the two veterinary scientists used immunohistochemistry (IHC) to find out              VeGf and VeGfr to a scientific journal for future publication.
whether VEGF and VEGFR are expressed in certain types of canine tumours.
protein pursuit                                                                               The researchers targeted mammary gland carcinomas as well as
      Although scientists know that VEGF is highly expressed in a number of            squamous cell carcinomas and fibrosarcomas — two malignant tumours
human tumour cells, very little work has been done to investigate the protein’s        arising in the skin and connective tissue of dogs. They also tested samples of
presence in canine cancer cells. Confirming this information is an important first     trichoepithelioma — a benign type of skin tumour that was compared to
step in determining whether anti-angiogenesis drugs would be effective in dogs.        squamous cell carcinoma. But besides searching for the expression of VEGF and
      The WCVM study also goes one step further than previous studies by               VEGFR in more than 100 tissue samples, Al-Dissi and Kidney also tested whether
searching for VEGF as well as for VEGFR — the receptor molecule that’s key to          the two proteins can be useful as accurate diagnostic and prognostic indicators.
initiating angiogenesis. When VEGF binds to VEGFR, that turns on a “signal”                   “We wanted to see if the cells are producing VEGF and VEGFR, and if so,
which triggers other molecular events involved in angiogenesis. “We thought it         are they producing a large volume of the proteins? We also wanted to know how
was important to look for both because if the receptor isn’t there to activate the     many cells are producing these proteins: is it a high or low percentage of cells?”
process, it wouldn’t matter how much VEGF was produced in the tumour cells.            explains Kidney. “Then, once we knew the proteins were there, we wanted to know
Nothing would happen,” explains Kidney.                                                if the expression level correlated with the degree of malignancy in the tumour.”


                                                                                                                                                                            6
    What Does That Mean?
    • angiogenesis: the formation of blood vessels. By growing its own
    network of blood vessels, a tumour gains a steady supply of oxygen and
    nutrients. That allows it to grow and spread to other parts of the host’s
    body.
    • immunohistochemistry (ihc): in this application, scientists use enzyme-
    flagged antibodies to identify patterns of antigen distribution in the tumour
    tissue. If the antibodies bind to the targeted proteins, its enzymes will
    convert a colourless substrate into a visible stain on a microscopic slide.
    The darker the stain, the higher the degree of protein (antigen) expression.
    • monoclonal antibody: a class of highly specific antibodies produced
    by the clones of a single hybrid cell (an antibody-producing B cell fused
    together with a fast-growing tumour cell). Since monoclonal antibodies
    recognize only one antigen, they’re used to bind to cancer-related antigens
    and to prevent them from performing their vital role in cancer growth and
    metastasis.
    • Growth factors: a variety of proteins that affect the growth of cells or
    organisms. In the past 20 years, scientists have been investigating and
    promoting the use of growth factors in treatments for certain types of
    cancers and blood-related diseases.


          By studying cells, oncologists and pathologists classify tumour biopsies as
    having low, moderate or high grades of malignancy (I being low grade, III being
    high grade). The degree of malignancy reflects the ability of cells to invade and to
    metastasize (the ability to spread to other organs).
          The researchers also used IHC techniques to collect additional data about
    microvessel density (the number of vessels associated with a tumour), Ki-67 (a
    protein that’s only present in dividing cells) and apoptososis (natural cell death
    — the number of dead cells in tumour tissue). Knowing more about all of these               Dr. Beverly Kidney: influenced by her background in diagnostic
    factors could potentially help to estimate a tumour’s degree of malignancy.                 pathology, dr. Beverly Kidney’s research interests mainly focus on
                                                                                                improving the accuracy of diagnostic tests. that includes new avenues
    high potential for clinical trials                                                          of disease testing such as evaluating gene expression for certain types
           Al-Dissi and Kidney found that more than 50 per cent of the cells in most            of cancer in dogs and cats. while the VeGf study was an ideal fit with
    of the malignant tumour samples expressed VEGF and VEGFR. “This is a good                   Kidney’s oncology research initiatives, this is her first investigation that
    start: now that we know that the proteins are highly expressed in these tumours,            targets a potential treatment for cancer.
    using anti-angiogenesis drugs to treat canine tumours is a real possibility for the               “when a medical oncologist joins our faculty, this will be one
    future,” explains Al-Dissi.                                                                 of the projects that could lead to clinical trials which incorporate
           The proteins’ potential as a prognostic tool for canine cancer patients              immunohistochemistry (ihc) techniques,” says Kidney.
    wasn’t so clear cut. VEGF and VEGFR expressions “moderately correlated” with                      another potential for Kidney is working with microarray analysis
    conventional malignancy grades in only one set of tissue samples: the squamous              — new technology that allows researchers to measure the expression of
    cell carcinoma tumours. As for other indicators, Ki-67 expression correlated with           hundreds of genes at one time.
    malignancy grades in two of the tumour types (mammary gland carcinomas and                        “for example, you could look at two different tumour groups and
    the fibrosarcomas).                                                                         compare the gene expression between them. or, you could look at the
           “Angiogenesis is a very complicated process involving more than 30 growth            expression in a malignant type of tumour that has spread versus another
    factors,” cautions Al-Dissi. “VEGF is one of the more important ones because of its         tumour that hasn’t spread and see what proteins are produced at
    role in blood vessel development, but other things could be going on that we don’t          different levels,” says Kidney.
    understand.”                                                                                      “the advantage of ihc has always been that we can look within a
           Although scientists still have a tremendous amount to learn about                    particular tumour cell and see what’s going on. But if we can use micro-
    angiogenesis in canine tumours, Al-Dissi believes enough is known to develop                array analysis to speed up that process, that would be very helpful.”
    clinical trials involving canine oncology patients. For example, since VEGF and
    VEGFR were highly expressed in several canine tumours, researchers could test
    the effectiveness of Avastin™ in combination with chemotherapy or radiation.                “We’re getting a lot closer, and once our work is published, that could help to
           Another study could also look at whether VEGF and VEGFR expressions             move things along,” says Kidney, adding that some of those future clinical studies
    correlate with patients’ life expectancy — a more realistic means of testing the       may take place at WCVM once the College adds a medical oncologist to its research
    proteins’ value as a prognostic indicator in dogs.                                     team.
           Of course, all of these steps take time, money and the involvement of more           “Research is a cumulative process,” says Al-Dissi. “We’re doing the first steps
    people in the research process — but what’s exciting is that the journey toward        and we’re hoping people will come after us to continue the work and come closer to
    developing anti-angiogenesis therapies for companion animals is on its way.            our ultimate goal: using this knowledge to treat cancer.” V


7
Bits & Bites                                                                                                           Canine Influenza Watch
                                                                                                                             canadian veterinarians are on the alert
                                                                                                                       for symptoms of canine influenza — a highly
                                                                                                                       contagious, respiratory infection that has
                                                                                                                       affected dogs across the united States.
                                                                                                                             the first recognized outbreak of canine
                                                                                                                       influenza occurred among racing greyhounds at
                                                                                                                       a florida track in January 2004, and since then,
                                                                                                                       outbreaks have been reported among other
                                                                                                                       populations of racing and pet dogs in nearly
                                                                                                                       two dozen states. the canine influenza virus
                                                                                                                       spreads to other dogs through direct contact
                                                                                                                       with infected dogs’ respiratory secretions or
                                                                                                                       through contact with contaminated equipment
                                                                                                                       or surfaces.
                                                                                                                             most affected dogs develop a mild form
                                                                                                                       of the influenza with signs similar to “kennel
canadians to the rescue: When Hurricane                  manitoba’s cover dogs: Last fall, the Manitoba                cough” (caused by Bordetella bronchiseptica)
Katrina hit New Orleans last summer, veterinary          Veterinary Medical Association (MVMA) sent a                  with a persistent cough lasting for 10 to 21
technologist Karen Harvey took time off from her job     unique donation to the Companion Health Fund:                 days. infected dogs may also have a thick,
at WCVM’s Veterinary Teaching Hospital to join other     two boxes of photos featuring dogs of all breeds,             nasal discharge caused by a secondary bacterial
veterinary professionals involved with the Canadian      shapes and sizes. More than 300 Manitoba pet                  infection. about 20 per cent of dogs develop
Animal Assistance Team (www.caat-canada.org).            owners sent in the pictures as part of a photo contest        more severe symptoms with high fevers (40°c to
      “CAAT sent 82 people in seven teams, and           organized by MVMA for its Great Manitoba Dog Party            41°c) and clinical signs of pneumonia.
we were the second team to go down South from            that was held in Winnipeg, Man., last May. But once                 Because this is a newly-emerging
Sept. 21-27,” says Harvey, who spent her first day       the winners were selected, the provincial veterinary          respiratory pathogen, all dogs are susceptible
caring for hundreds of cats, dogs and exotic pets in     association was reluctant to have the collection              to infection and have no naturally-acquired
a temporary camp at Gonzales, La. But as Hurricane       languish in storage.                                          or vaccine-induced immunity. however, the
Rita blew in, Harvey and her coworkers had to find             That’s when the event’s organizing committee            disease’s mortality rate is low: between one
refuge with a fellow volunteer from Baton Rouge,         thought of the Fund. Since MVMA has rights to all             and eight per cent of patients have died from
La., who took in all of the Canadians for the rest       images, the committee’s volunteers offered to donate          complications caused by the infection.
of their stay. Two days later, the weather improved      the photos for future use in fund raising initiatives               Based on studies conducted at the
enough so team members could work at a New               and other projects. CAHF now plans to use some                university of florida and cornell university,
Orleans triage centre. There, they conducted physical    of the prize-winning photography to produce new               the canine influenza virus is a mutated form
examinations of about 200 animals per day, then          note cards as a means of raising money for WCVM’s             of h3n8, an equine strain of influenza virus.
treated them for dehydration and heat exhaustion         companion animal health research and training                 “what’s really interesting is that equine
before transporting them to Gonzales.                    programs. Plus, dog enthusiasts can enjoy images              influenza has made it into dogs and is now
      Harvey also took her turn at searching for         like the one above in upcoming Vet Topics (each               being transferred from one dog to another,”
pets: “We saw sad cases where animals hadn’t             printed photo will be accompanied by the names of             says dr. hugh townsend, a wcVm professor who
survived, so it felt good when we found a pet that       the dog and photographer as well as recognition for           has studied equine influenza virus for nearly
was still alive. One lady told us that she was feeding   MVMA).                                                        two decades.
sandwiches to a dog, so we went to the house and               “Having access to such a large collection of                  however, townsend points out that there’s
found a Rottweiler — a real sweetheart. Her fence        photos that features healthy, happy dogs in their             no evidence to suggest that canine influenza can
had blown down, but she was too scared to leave her      own homes and yards is extremely beneficial to our            be transmitted from dogs to humans. another
yard.”                                                   fund raising efforts,” says Dr. John Pharr, editor            reassuring factor is that the equine influenza
      The exhausting week was filled with                of Vet Topics and chair of CAHF’s advisory board.             virus, which has been found in horses for more
challenges and extreme weather, but the veterinary       “We’re grateful to MVMA and to all of the Manitoba            than 40 years, has never caused infection in
technologist plans to volunteer again. “We gained        dog owners who participated in the contest. Their             people.
valuable experience in Louisiana,” says Harvey, who      eye-catching photos will help us to attract more
now works at a B.C. emergency practice. “We have a       interest in our animal health programs for many               For more information, visit:
much better idea of what needs to be done and what       years to come.”                                               • American Veterinary Medical Association
to expect for next time.”                                                                                              (www.avma.org)
                                                                                                                       • Centers for Disease Control and Prevention
                                                                                                                       (www.cdc.gov/healthypets
                                    check out Vet Topics online at www.cahf.usask.ca
                                                                        puBlicationS mail aGreement no. 40112792
                                                                  RETURN UNDELIVERABLE CANADIAN ADDRESSES TO:
                                                                                             Research Office, WCVM
                                                                                                                       above: this photo of “molly” won first prize in the
                                                                                          University of Saskatchewan   mVma photo contest’s puppy category. photographer:
                                                                                                    52 Campus Drive    roger laurenzo, winnipeg, man. Courtesy of the
                                                                                             Saskatoon SK S7N 5B4      MVMA Great Manitoba Dog Party Photo Contest.
                                                                                     E-mail: wcvm.research@usask.ca


                                                                                                                                     printing Services • 966-6639 • university of Saskatchewan • cupe 1975

				
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