WSVMA Annual Conference The Wellness Plan for Senior Dogs and Cats: It Just Makes Good Sense & Practical Parasitology: The Cool Stuff Spokane Convention Center Spokane, Washington October 1-3, 2010 Sandy Willis, DVM, DACVIM Phoenix Central Laboratories, Everett, WA
Saundra E. Willis DVM DACVIM (SA) Phoenix Central Laboratory Everett, WA Biography: Dr. Sandy Willis is the small animal internal medicine consultant for Phoenix Central Laboratory. She is also CE Chair for Phoenix lab, organizing seminars and wet labs for veterinary staff. Dr. Willis is board certified in the American College of Internal Medicine. She graduated from UC Davis School of Veterinary, completed a small animal internship at the University of Minnesota and a residency at the University of Saskatchewan. She is past president of the SKCVMA and WSVMA, Program Chair for the WSVMA and Alternative Delegate to the AVMA. Dr. Willis is President of the Feral Cat Spay and Neuter Project. Contact Email: sandy7957@comcast.net
The Wellness Plan for Senior Dogs and Cats It Just Makes Good Sense Saundra E. Willis DVM DACVIM (SA) Phoenix Central Laboratory for Veterinarians The goal of this session is to make you true believers in senior wellness plans for cats and dogs. We will discuss diseases seen in older dogs and cats that might have had a different outcome had the problem been discovered earlier. We will then discuss cases where significant disease was detected on routine blood screening in apparently healthy seniors. And lastly, we will show some examples of small blood screening abnormalities and how their significance, and lack of significance, was determined and communicated with the owner. Then together (after all, this is an interactive session) we will create a wellness plan for seniors including tools for client communication that you can bring back and implement in your practices. SO LET S GET STARTED How many of you have a senior dog or cat? Before you can answer that question, we need to determine how the term senior is defined. At what age is a dog or cat a senior? Hint: it depends on size of the pet and therefore, a bit on breed: Do you think this definition has changed over, say the last 25 years? Old age is not a disease. We see more diseases in older pets but being old is not a disease in itself. What are some diseases that we see in senior dogs and cats? How many of you have dogs and/or cats with each disease? What are some common symptoms or clinical signs of these diseases? What are the initial test(s) that we use to help diagnose these diseases? In general terms, how do we manage each of these diseases? 1
And lastly, put a check by those diseases that, if identified early, a treatment program would delay the onset of clinical signs and provide the pet a longer life while maintaining a good quality of life. Another way of stating this, in which diseases might the outcome have been different if we had detected it earlier? Dog Disease Clinical Signs Diagnostic Tests Management Early Diagnosis? Cat Disease Clinical Signs Diagnostic Tests Management Early Diagnosis? Subtle Clinical Signs We talked about clinical signs associated with some of these diseases, but what are some other important clinical signs that owners should look for in their pets that should prompt concern and a visit to the veterinarian? 2
Some case examples Let s start with William or Bill as he is known by his neighborhood buddies. Bill is a roughly 15 year old male castrated cat with the most evil glare of any cat I have ever known. When roused, his glare will send cats, people, and wild dogs running. And when he is really upset, he urinates.everywhere. Notes on cases: I have presented some examples of significant laboratory abnormalities in seemingly healthy senior dogs and cats. We have discussed how recognizing problems early before pets show clinical signs can lead to medical intervention that will delay onset of disease, improve chances for cure, and provide a longer and better quality of life in the golden years. But what other information might an owner like to have? Statistics on disease in senior dogs and cats: Personal stories/recommendations for the hospital staff: Keep in mind that recommendations for pet health should come from the family veterinarian and not from friends and family, pet health websites, talk shows, etc. And if nothing else, a Wellness Plan for a senior dog or cat buys the owner PEACE of MIND, knowing that their beloved pet looks and truly is healthy. Creating a Wellness Plan for Senior Dogs and Cats What do you want to include? What laboratory testing would you do? Urinalysis? Thyroid? 3
Blood Pressure? Any imaging (xrays)? Communicating this program to clients Who would do the communication? Veterinarian, veterinary technician, receptionist? When would this be done? In the exam room? When the appointment is made on the phone? How would this be done? Verbally at the time of an appointment? Using pamphlets provided at the appointment time? By mail? By email? On the website? What do you think would be the greatest obstacles you would have to overcome, and their possible solutions, that would stand in the way of a client accepting a wellness program for this pet? Obstacle Solution What is one idea you have learned from this session that ignites your excitement for a Wellness Plan for your clinic s senior dogs and cats? The Wellness Plan for Senior Dogs and Cats: It is the right thing to do. 4
Practical Parasitology The Cool Stuff Saundra E. Willis DVM DACVIM (SA) Phoenix Central Laboratory for Veterinarians Principles Routine fecal exams are an important part of the preventative health care program for cats and dogs. The frequency that fecal exams are done depends on the environmental exposure of the pet, travel history, health status of the pet and age. Younger and older pets are most susceptible to parasitic disease. The Companion Animal Parasite Council (CAPC) is an independent council of veterinarians and other health care professionals that establish guidelines for the optimal control of internal and external parasites in pets. These guidelines, as well as a myriad of information on different parasites, parasitology updates, and CAPC educational events can be found at www.capcvet.org. CAPC brochures are available for clinics to distribute to pet owners and there is a companion site, www.petsandparasites.org, designed for pet owners. Many veterinary clinics have adopted these very strict guidelines to ensure optimal health for their pets and by limiting the zoonotic potential of gastrointestinal parasites, to their clients. CAPC recommends year round treatment with broad-spectrum heartworm anthelmintics with activity against parasites with zoonotic potential. They recommend regular fecal examinations (using centrifugation method) 2-4 times a year during the first year of life and thereafter 1-2 times a year for adult pets in conjunction with a physical examination. In puppies and kittens, the risk of parasite infestation is greater. The young can be serially reinfected from mom during nursing and/or the environment. Pups and kittens can also harbor migrating parasites from the gut without the infestation being patient, i.e. no eggs are seen on a fecal exam. For puppies, use a broad spectrum anthelmintic at 2, 4, 6, 8 weeks followed by a monthly preventative.. For kittens, treat with a broad spectrum anthelmintic at 3, 5, 7, 9 weeks then administer a monthly preventative. Mom should be treated as well. It is always important to tailor anthelmintic treatment to the needs of the individual pet. Our pet owners should be aware of the zoonotic potential, i.e. transmission of parasites from pets to man, of certain of our parasites. Ascarids (roundworms) and hookworms are of main concern; tapeworms can be in those areas endemic for echinococcus. Baylisascaris, the raccoon tapeworm is of zoonotic importance in our area. Leaving pet food outside should be discouraged so that raccoons do not establish a feeding, and latrine area, around pets and people. Make sure your clients are aware of risks and explain that a strict program of multiple fecal exams and an anthelmintic program are important to significantly reducing risk of zoonotic disease from our pets. 5
As much as fecal examinations are important in the healthy pet, fecal exams and prophylactic deworming are an essential first step in disease. Such clinical signs as vomiting and diarrhea, anorexia, weight loss and skin/hair coat problems should prompt a look for parasites and treatment. Sometimes whip and hook worms infections can be so severe as to result in significant changes reminiscent of malabsorptive/maldigestive gastrointestinal disease, even neoplasia. Some of these infections are only found on endoscopy as fecal exams can be falsely negative, thus it is important to give a round of anthelmintic just in case the problem is parasitical before considering a more invasive procedure like biopsy. Feces can be collected and submitted in nearly any container. It is ideal to have the freshest sample possible but a natural collection is better than a fecal loop. Most testing requires one to two grams of feces, one gram defined as a cube 0.5 inch on a side. Feces left outside for awhile may attract secondary invaders such as fleas, grain mites, etc. and sometimes it can be difficult sorting through these artifacts. Some labs provide special plastic containers for the feces but anything clean and sealed, including plastic bags, will work. Make sure each sample is labeled with the owner and pet names, as well as the clinic information if sending to an outside laboratory. Date of sample collection is also be important. Fecal Flotation Using Centrifugation A complete exam should start out with a direct smear. This technique detects worms, larvae and all things motile and living. This may be the only time we see giardia and occasionally we detect spirochetes by this method. The second step is the fecal flotation. The principle behind flotation is that parasites and other objects in feces are separated based on their density compared to the flotation solution. When parasites are lighter than the density of the solution (measured as specific gravity) they will float to the top while heavier objects, the debris, sinks. With passive or tabletop flotation, parasites rise slowly to the surface passively with buoyant force. With centrifugation, a greater force is placed on the heavier objects and they sink more rapidly and therefore separate more efficiently from the parasites. Most practices use a flotation solution of specific gravity between 1.18 and 1.27. The greater the specific gravity, the denser the flotation solution allowing more parasite eggs to float to the top. This increases the sensitivity of the solution. The specific gravity is a balance however, as a more concentrated solutions may dehydrate the eggs and distort them. Sodium nitrate (SG 1.18-1.20) is used in most veterinary practices as it is available commercially. Zinc sulfate is also used, and can be prepared at specific gravity of 1.18-1.20 and 1.29. Many veterinary laboratories prefer to use Sheather s Sucrose Solution prepared at a specific gravity of 1.27. A sucrose solution floats more parasite eggs without distorting egg morphology. Unlike most of the other flotation solutions, Sheather s Solution does not crystallize. The take home message: To increase diagnostic yield of your in-house fecal flotation, use active flotation via centrifugation rather than passive flotation and an optimal density flotation solution. 6
Technique Whipworm Roundworm Hookworm Direct Smear 92.61% 85.38% 72.82% Ovassay 32.02% 25.88% 4.85% Centrifugation 4.93% 10.53% 0.97% % for false negative results Comparison of Common Fecal Flotation Techniques for Recovery of Parasite Eggs and Oocysts. Dryden MW et al, Veterinary Therapeutics Vo1. 6, No. 1, Spring 2005. The fecal exam protocol used at Phoenix Central Lab is as follows: Step 1: Direct Mount Examine the fecal sample macroscopically for worms and larvae. Prepare a wet mount slide of the fecal sample in a drop of saline or water. Examine the slide for motile parasites, worms and other larvae. Record results. Step 2: Double Centrifugation Flotation using Sheather s Sucrose Solution 1). Prepare a fecal emulsion using approximately 1 gram of feces in 10 12 mls. of water in a paper cup. 2). Strain the emulsion through a gauze square into another paper cup. 3). Label one 15-ml. conical centrifuge tube with the specimen number. Pour the fecal emulsion into the labeled tube to the 15 ml. mark. 4). If necessary, add water to the tubes to balance them. 5). Centrifuge the tube for 10 minutes at 1,500 rpm. 6). When the centrifugation is complete, decant the supernatant into a biohazard box leaving intact the fecal material at the bottom of the tube. 7). Add the sugar solution to the halfway point of the specimen tube. 8). Mix the fecal material completely with the flotation solution using a wooden applicator stick. Make sure that new sticks are used with each sample such that cross contamination of samples does not occur. 9). Add more of the sugar solution to the tube to reach the 15-ml. mark. 10). Centrifuge the tube for 10 minutes at 1,500 rpm. 11). When the centrifugation is complete, carefully set the tube upright in a test tube rack. Using a plastic pipette, gently run additional sugar solution down the side of the tube disturbing the contents as little as possible. Create a slight positive meniscus and set a 22-mm. square cover slip on top. 12). Let the tube stand for 5 10 minutes. 13). Remove the cover slip by lifting straight up and place the cover slip on a clean slide. Label the slide with the patient number. Systematically examine the entire area under the cover ship at 10X and then 40X magnification. Note findings in the record. 7
Sheather s Sucrose Solution (specific gravity 1.027) 1). Heat 360 mls. (1.5 cups) of water just to boiling. 2) Add 454 grams (2.25 cups) of granulated white sugar. 3). Mix until completely dissolved. 4). Pour into plastic container and lid immediately. 5). Store at 4 C for long periods of time. Store at room temperature when the container is being used daily. The Parasites Common gastrointestinal parasites in the Pacific Northwest include Roundworms: Toxocara and Toxascaris; Coccidia: Isospora, Giardia, Toxoplasma; Tapeworms: Dipylidium and Taenia; Hookworms: Ancyclostoma and Uncinaria; Whipworms: Trichuris; Flukes: Nanophyetus. In horses, we see Strongyles of various species, Parascaris (roundworm), Anoplacephala spp (tapeworm), Eimeria leuckarti (coccidian), Strongyloides (threadworm) and Nematodirus (thread-necked worm). In Alpacas, sheep, goats and other ruminants we see Stronglyes, the coccidia Eimeria and Isospora, Nematodirus, Capillaria, Trichuris (whipworm) and Monieza. Nematodes: Roundworms: Canine: Toxocara canis Toxascaris leonina Feline: Toxocara cati Toxascaris leonina Racoon: Baylisascaris procyonis Points to remember: 1. Migration of larvae in liver and lungs 2. Contaminated environment an important source of infection 3. T. canis can be transmitted transplacentally 4. Disease in puppies and kittens presents as ill thrift, pot bellied appearance 5. Disease sometimes seen in adult cats, rare in adult dogs 6. Public Health: Important zoonotic potential Appearance: Hookworms: Canine: Ancyclostoma caninum Ancyclostoma braziliense Uncinaria stenocephala Feline: Ancyclostoma tubaeforme Ancyclostoma braziliense Points to remember: 8
1. A. caninum can be transferred through the milk 2. Hookworms attach to the small intestine by a large mouth cavity. They suck blood and the resulting anemia results in weakness and even death 3. There can be lung migration of larvae 4. Eggs last for shorter time in environment than roundworms 5. Pups can die of anemia before ova appear in feces 6. Public Health: Important zoonotic potential; larvae can penetrate skin Appearance: Whipworms: Canine: Trichuris vulpis Points to remember: 1. Whipworms mainly live in the cecum 2. Eggs persist in the environment 3. Affected dogs can be asymptomatic, to having blood diarrhea, weight loss, and dehydration 4. There is a long prepatent period after infection before ova are seen on fecal exam 5. Eggs are dense and sugar solution is most sensitive flotation solution for these eggs Appearance: Cestodes: Tapeworm: Canine: Feline: Dipylidium caninum Taenia pisiformis Echinococcus granulosus Echinococcus multilocularis Dipylidium caninum Taenia taeniaeformis Echinococcus multilocularis Points to remember: 1. Intermediate host needed (D. caninum: fleas, Taenia: rabbits) 2. Disease is rare; proglottids are seen in the feces 3. Echinococcus not endemic to Washington State: seen in NC, MD, SW, CN, AL Appearance: 9
Trematode: Fluke Canine: Nanophyetus salmincola Points to remember: 1. Cause salmon poisoning disease due to Neorickettsia helminthoeca 2. Clinical signs of fever, anorexia, vomiting and diarrhea 3. Diagnosis is made by finding Nanophyetus eggs on fecal exam 4. Life cycle: dog passes Nanophyetus, which harbors the Neorickettsia. Fluke life cycle completes through first intermediate host being the snail of coastal PNW, and then free living stage penetrates second intermediate host including salmon, nonsalmonoid fish, and Pacific Giant Salamander. Dog can be infected by eating or even licking the fish or salamander. 5. There is no blood test to detect the Neorickettsia 6. Treatment is with doxycyline and supportive care Appearance: Protozoa: Coccidia: Unsporulated large oocysts Canine: Isospora canis Feline: Isospora felis Unsporulated small oocysts Toxoplasma gondii Sporulated very small oocysts Cryptosporidium spp. Giardia spp. Size Comparison: I. canis, I. felis: 38-51 x 27-39 um Toxoplasma: 11-14 x 9-11 um Giardia cyst: 9-13 x 7-9 um Points to remember 1. Disease syndrome is generally diarrhea, anorexia, vomiting, weight loss 2. Infections can be asymptomatic; underlying disease may be present 3. Environmental contamination is important; sanitation important for control 4. Species tend are generally species specific 10
5. Emeria spp does not cause disease in dogs/cats Appearance: Large Animal Gastrointestinal Parasites: Strongyles Eimeria Namatodirus Strongyloides Trichuris Anoplacephala Parascaris Moniezia Capillaria Pseudoparasites (specimens mistaken for parasites) Alternaria spp Emeria spp (in small animals). Free living nematode Spurious Parasites (just passing through) Grain mites and eggs Pollen Granules 11