Hartz Companion Animal - Wolbachia and Heartworm Disease


Published on

Dirofilaria immitis is the causative agent
of canine and feline heartworm disease.
Adult worms live in the pulmonary
arteries, and females produce first-stage
larvae (microfilariae), which are taken up
by mosquitoes that then transmit the
infection to other animals. In dogs, an
untreated infection leads to congestive
heart failure (Figures 1 and 2). D. immitis,
like most filarial worms studied to date,
harbor bacteria called Wolbachia, which are
thought to play an essential role in the
biology and reproductive functions of their
filarial hosts.Wolbachia pipientis, the only
species thus far identified in the genus,
are gram-negative bacteria belonging to
the order Rickettsiales (just like Ehrlichia
spp and Anaplasma spp).

1 Like
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

Hartz Companion Animal - Wolbachia and Heartworm Disease

  1. 1. A NEWSLETTER OF PRACTICAL MEDICINE FOR VETERINARY PROFESSIONALS SEPTEMBER 2006 VOLUME 4, NUMBER 3 Wolbachia and Heartworm Disease Laura H. Kramer, DVM, PhD, DEVPC College of Veterinary Medicine University of Parma, Parma, Italy Dirofilaria immitis is the causative agent developing embryonic stages within the Wolbachia increases its own fitness byof canine and feline heartworm disease. uteri. This suggests that the bacterium is increasing the fitness of the hostAdult worms live in the pulmonary vertically transmitted through the involved in its transmission.arteries, and females produce first-stage cytoplasm of the egg.1 s Removal of Wolbachia (via antibioticslarvae (microfilariae), which are taken up or radiation) leads to sterility of femaleby mosquitoes that then transmit the ROLE OF WOLBACHIA IN worms and eventual death of adults.infection to other animals. In dogs, an ITS FILARIAL HOSTuntreated infection leads to congestive Human research has revealed several It is still unclear, however, exactly whatheart failure (Figures 1 and 2). D. immitis, reasons why the presence of Wolbachia is Wolbachia does to make it so importantlike most filarial worms studied to date, thought to be essential for a filarial for its filarial host. It has been suggestedharbor bacteria called Wolbachia, which are worm’s survival: that, while the filarial worm likely suppliesthought to play an essential role in the s the bacteria with amino acids necessary In those species of filarial worms thatbiology and reproductive functions of their for growth and replication, Wolbachia may have been identified as harboringfilarial hosts. Wolbachia pipientis, the only produce several important molecules that Wolbachia, all of the individuals arespecies thus far identified in the genus, are essential for heartworms, such as infected (i.e., 100% prevalence).are gram-negative bacteria belonging to glutathione and heme.2 It is indeed a “one s The evolution of the bacteria matchesthe order Rickettsiales (just like Ehrlichia hand washing the other” situation thatspp and Anaplasma spp).1 In adult D. that of the filarial worms, andimmitis, Wolbachia is predominantly found phylogenic studies have shown thatthroughout cells in the hypodermis, which the two organisms have been “walkingis directly under the worm’s cuticle (Figure hand-in-hand” for millions of years. ALSO IN THIS ISSUE:3). In female D. immitis, Wolbachia is also s The bacteria are transmitted from Deworming Demystified............ 4present in the ovaries, oocytes, and female to offspring and, in this way,
  2. 2. A NEWSLETTER OF PRACTICAL MEDICINE FOR VETERINARY PROFESSIONALS SEPTEMBER 2006 VOLUME 4, NUMBER 3 Consulting Editors Albert Ahn, DVM Vice President of Corporate Communications and Consumer Relations The Hartz Mountain Corporation Figure 2. Radiograph of the dog Bruce Truman in Figure 1. Note the enlarged cardiac Senior Director Figure 1. A 6-year-old Great Dane chambers (white arrows), thickened Animal Health and Nutrition with chronic heartworm disease. Note the pulmonary arteries (yellow arrow), and weight loss (apparent by the noticeable interstitial inflammation. (Photo by Dr. Luigi The Hartz Mountain Corporation spine and rib cage) and dilated abdomen Venco) (due to ascites). (Photo by Dr. Luigi Venco) Associate Editors disease. Bacteria were observed in the Jill A. Richardson, DVM may, however, be the key to novel lungs and particularly in organs where Director strategies for the control/treatment of microfilariae normally circulate, such as the Consumer Relations filarial infection, including canine and kidney and liver. Furthermore, when we The Hartz Mountain Corporation feline heartworm disease. looked at specific antibody responses to David Levy Wolbachia, we observed a stronger response Assistant Manager ROLE OF WOLBACHIA IN in dogs with circulating microfilariae Animal Health and Nutrition THE INFLAMMATORY AND compared with dogs with occult infection, The Hartz Mountain Corporation IMMUNE RESPONSE IN D. supporting the hypothesis that microfilarial HARTZ® COMPANION ANIMAL SM IMMITIS–INFECTED ANIMALS turnover is an important source of Wolbachia in dogs with heartworm disease. is produced for The Hartz Mountain As gram-negative bacteria, Wolbachia Corporation by Veterinary Learning have the potential to play an important role Furthermore, Wolbachia from D. immitis Systems, 780 Township Line Rd., in the pathogenesis and immune response have been shown to provoke chemokinesis Yardley, PA 19067. to filarial infection. The possible and proinflammatory cytokine production consequences of the massive release of in canine neutrophils. Cats with Copyright © 2006 The Hartz Mountain Wolbachia in the filaria-infected host have heartworm disease also produce antibodies Corporation. All rights reserved. been evaluated. Wolbachia are released both to Wolbachia. Interestingly, it has recently Hartz® and other marks are owned by by living worms and after worm death been reported that the development of a The Hartz Mountain Corporation. through natural attrition, microfilarial strong antibody response against D. immitis occurs after 1 to 2 months of infection, Printed in U.S.A. No part of this turnover, and pharmacologic intervention.3 publication may be reproduced in any In human and murine models of infection, which has important implications for early form without the express written the release of bacteria has been shown to diagnosis.5 permission of the publisher. be associated with the up-regulation of Areas of future research should include proinflammatory cytokines, neutrophil the possible diagnostic use of specific For more information on The Hartz recruitment, and an increase in specific immune responses to Wolbachia, its Mountain Corporation, visit potential immunomodulatory activity www.hartz.com. immunoglobulins. Ongoing studies in dogs with heartworm disease may shed light on (prevention), and the effects of antibiotic what happens when infected animals come treatment in infected animals. synthetic derivatives appear to be the into contact with the bacteria. For example, most effective) are able to drastically my colleagues and I recently tested the EFFECT OF ANTIBIOTIC reduce if not completely remove the hypothesis that D. immitis–infected dogs TREATMENT ON FILARIAL endosymbiont from the worm host. Such come into contact with Wolbachia either WORMS depletion of Wolbachia is then followed by through microfilarial turnover or natural Wolbachia can be eliminated from clear antifilarial effects, including: death of adult worms.4 In our study, filarial worms through antibiotic therapy positive staining for Wolbachia was of the infected host. Numerous studies s Inhibition of larval development: observed in various tissues from dogs that have shown that various treatment It has been shown that antibiotic had died because of natural heartworm protocols and dosages (tetracycline and treatment of filaria-infected hosts can2 HARTZ COMPANION ANIMAL ® SM • SEPTEMBER 2006 • VOL. 4, NO. 3
  3. 3. ADDITIONAL CONSIDERATIONS FOR ADULTICIDE THERAPY—WOLBACHIA Most filarial nematodes, including D. immitis, harbor obligate, intracellular, gram- negative bacteria belonging to the genus Wolbachia (Rickettsiales). In infections with other filarial parasites, treatment with tetracyclines during the first month of infection was lethal to some Wolbachia-harboring filariae but not to a filariae that did not harbor Wolbachia, and treatment of Wolbachia-harboring filariae suppressed microfilaremia. Similar prophylaxis studies with D. immitis have not been reported, but in one study, tetracycline treatment of heartworm-infected dogs resulted in infertility in the female worms. These bacteria also have been implicated in the pathogenesis of filarial diseases, possibly throughFigure 3. Cross–section of an adultfemale Dirofilaria immitis stained with a their endotoxins. Recent studies have shown that a major surface protein of Wolbachiapolyclonal antibody against the Wolbachia (WSP) induces a specific IgG response in hosts infected by D. immitis. It is hypothesizedsurface protein. Note the numerous that Wolbachia contribute to pulmonary and renal inflammation through the surfacebacteria (arrows) that almost entirely fill protein WSP independent of its endotoxin component. Studies to determine the effectsthe cell of the lateral hypodermal cord. of suppressing Wolbachia populations with doxycyline prior to adulticide therapy will be(Original magnification x40) required to determine the clinical utility of this therapeutic approach. inhibit molting, an essential process From: Guidelines for the Diagnosis, Prevention and Management of Heartworm ( Dirofilaria immi- tis) Infection in Dogs; reprinted with permission of the American Heartworm Society. Available in the maturation of worms from at www.heartwormsociety.org; accessed August 2006. larvae to adult.s Female worm sterility: Antibiotic treatment leads first to a reduction ultrasonography in 21 of 27 patients. worm. There are little data concerning the and then to the complete and In the other patients, the number of effects of antibiotic treatment in dogs with sustained absence of microfilariae. scrotal worm nests declined. This was natural heartworm disease; what is known, Researchers at the University of significantly different from placebo however, is that such treatment drastically Milan, Italy, have reported that D. patients in which lack of worm nests reduces Wolbachia loads in D. immitis. immitis adults taken from naturally was only observed in three of 27 Preliminary trials8 in naturally infected infected dogs that had been treated patients. This is the first report of dogs have shown that doxycycline treatment with doxycycline at 20 mg/kg/day antibiotic-induced adulticide activity before adulticide therapy with melarsomine for 30 days showed morphologic in a human filarial worm. Could may help reduce proinflammatory reactions alterations of uterine content with a antibiotic treatment have the same due to the death of adult worms (as seen dramatic decrease in the number of effect on D. immitis? Several research by lower antibody levels against Wolbachia mature microfilariae, indicating that groups, including our laboratory, are and lower levels of interleukin-8, an bacteriostatic antibiotic treatment curently attempting to answer this very inflammatory cytokine involved in was able to block embryogenesis.6 important question. neutrophil recruitment). These results haves Adulticide effects: This is a particularly encouraged our laboratory to continue to intriguing aspect of antibiotic treatment EFFECTS OF ANTIBIOTIC evaluate the clinical benefits of antibiotic of the filarial worm–infected host and TREATMENT ON THE FILARIAL treatment in naturally infected dogs. one that merits strict attention. Clinical WORM–INFECTED HOST Given the recent and very promising trials in human filariasis have reported It is very likely that antibiotic treatment developments in the use of tetracyclines extremely promising results: A recent will have some beneficial effects on subjects for micro- and macrofilaricidal therapy in placebo-controlled trial in humans with filariasis. First, the effects on the human filariasis, it is hoped that similar infected with Wuchereria bancrofti has worm (described above) will themselves attention will be given to canine and demonstrated a clear macrofilaricidal lead to improved clinical presentation, feline heartworm disease, which could (i.e., adulticidal) effect of doxycycline.7 such as a reduction in the circulating greatly benefit from alternative When administered for 8 weeks at 200 microfilariae that have been implicated in therapeutic strategies. mg/day, doxycycline treatment resulted immune complex formation during in complete amicrofilaremia in 28 of 32 infections.4 However, if Wolbachia is REFERENCES 1. Bandi C, Trees AJ, Brattig NW: Wolbachia in filarial patients assessed and a lack of worm considered a potential cause of nematodes: Evolutionary aspects and implications for nests in the scrotum (where adult inflammation in the course of filarial the pathogenesis and treatment of filarial diseases. Vet Parasitol 98:215–238, 2001. worms reside) at 14 months after disease, depletion of the bacteria may be 2. Foster J, Ganatra M, Kamal I, et al: The Wolbachia treatment, as determined by beneficial independent of its effect on the genome of Brugia malayi: Endosymbiont evolution (continues on page 8) HARTZ® COMPANION ANIMALSM • SEPTEMBER 2006 • VOL. 4, NO. 3 3
  4. 4. Deworming Demystified: Update on Deworming Protocols Byron L. Blagburn, MS, PhD Distinguished University Professor Department of Pathobiology College of Veterinary Medicine Auburn University Parasites are important causes of that can eliminate many parasites, often Discretionary Deworming disease in dogs and cats of all ages (Table including both internal and external Discretionary deworming is based on a 1) but can be particularly important in parasites) (Table 2). The language becomes perceived need to deworm, such as results puppies and kittens because of their small even more confusing when one considers of fecal examination or other diagnostic size, developing immunity, and other that some single-entity products have tests (e.g., elevated eosinophil count, stresses associated with growth and broad-spectrum activity (e.g., pyrantel radiographic evidence of pulmonary maturation. Young pets are often exposed pamoate, milbemycin oxime) and that parasitism). As the name implies, to and acquire parasites differently than combining products may or may not discretionary deworming is performed at older pets. Because of their increased increase the spectrum of internal parasites the discretion of the veterinarian. In my exposure and susceptibility, they often eliminated (e.g., ivermectin–pyrantel view, discretionary deworming should be harbor greater numbers of parasites than pamoate versus milbemycin oxime– performed only based on knowledge mature animals. Heavier parasite burdens lufenuron). gained from history or presenting signs, place puppies and kittens at greater risk of appropriate diagnostic procedures, or disease and also lead to higher shedding Strategic Deworming other information sufficient to warrant rates of fecal stages into the environment. Strategic deworming is the application the use of parasiticides. Increased environmental contamination of a specific parasite-control strategy also increases the risk of human exposure based on an individual pet’s age, Targeted Deworming to zoonotic roundworms and hookworms. environment, and likelihood of exposure Targeted deworming, in my opinion, This article reviews strategies for to parasites, prevalence of the parasite in is just another term for strategic deworming dogs and cats. Available question, and geographic region. An deworming. The intent is to “target” parasiticides now allow important example of strategic deworming would be particular time points based on criteria parasites to be eliminated safely and deworming puppies at 2, 4, 6, and 8 mentioned above for strategic deworming pets to be maintained free of parasites weeks of age to control migrating stages (i.e., age, environment, history of prior throughout their lives. of roundworms and hookworms parasitism or exposure to parasites, and (discussed below). Additional examples geographic region). SOME DEWORMING include strategically placed intervals DEFINITIONS between dewormings throughout the year, Interval Deworming Several terms have been used to define such as every 6 months or every 3 months Interval deworming is deworming the various approaches to internal parasite for pets with a seasonal likelihood of pets at specific intervals. The approach control and the available parasiticides. exposure to parasites or if control of a is similar to strategic or targeted Deworming terms include “strategic,” specific parasite, such as whipworm, is deworming, but with less attention given “discretionary,” “targeted,” and “interval,” needed. Strategic deworming may also to specific reasons for selecting time and parasite control products are identified include a strategy of monthly, year-round, points. Interval deworming is usually as single entity (one active ingredient), broad-spectrum internal parasite control intended to provide a “safety net,” based combination (more than one active to improve compliance and take on the presumption that pets are likely ingredient), narrow spectrum (products that advantage of heartworm preventives to be exposed to parasites but without are capable of removing one or two or flea-control products with activity specific knowledge of when that exposure parasites), and broad spectrum (products against important internal parasites. is likely to occur.4 HARTZ COMPANION ANIMAL ® SM • SEPTEMBER 2006 • VOL. 4, NO. 3
  5. 5. TABLE 1: Common Nematode Parasites of Dogs and Cats Prevalence/ Site of Parasite Geographic Development Developmental Diagnostic Procedure/ Zoonotic (Common Name) Host(s) Location (Adult Worms) Life Cycle Period Stage in Feces Potential Toxocara canis Dogs High/ Small Infection by embryonated eggs 28–35 days Fecal flotation/non- Very (canine throughout intestine and transplacental transmission; embryonated eggs high roundworm) the US larvae undergo liver–lung are 90 × 75 µm, migration; rodents may serve as subglobular, with transport hosts; transmammary thick pitted shells transmission is uncommon Toxocara cati Cats High/ Small Direct infection by embyronated 38–56 days Fecal flotation/non- Very (feline throughout intestine eggs and transmammary embryonated eggs high roundworm) the US transmission; rodents may serve are 65–75 µm; as transport hosts; larvae may similar to T. canis undergo liver–lung migration; eggs but smaller transplacental transmission apparently does not occur Toxascaris Dogs Low/ Small Direct infection by embryonated 74 days Fecal flotation/non- None leonina and throughout intestine eggs; rodents may serve as embryonated eggs (nonmigratory cats the US; transport hosts; development is are 80 × 70 µm, roundworm) distribution restricted to small intestine; no slightly oval with a spotty extraintestinal, transplacental, or smooth shell transmammary transmission Ancylostoma Dogs High/ Small Direct infection by ingestion or 15–18 days Fecal flotation/non- High caninum (canine throughout intestine skin penetration; may undergo embryonated eggs hookworm) the US; more lung migration; ingested larvae are 70 × 40 µm common in may mature without lung warmer migration; rodents may serve as climates transport hosts; the principal route of infection is transmammary Ancylostoma Cats High/ Middle small Direct infection by ingestion or 16–25 days Fecal flotation/non- Low tubaeforme throughout intestine skin penetration; larvae may embryonated eggs (feline the US; more undergo lung migration; rodents are 61 × 40 µm hookworm) common in may serve as transport hosts; no warmer transmammary or transplacental climates transmission Ancylostoma Dogs High in tropical Anterior Direct infection by ingestion or 14–27 days Fecal flotation/non- High braziliense and and subtropical small skin penetration; larvae may embryonated eggs (subtropical cats regions/limited intestine undergo lung migration; rodents are 55 × 34 µm; not hookworm) to Florida and may serve as transport hosts; no easily differentiated Golf Coast information on transmammary from A. tubaeforme or transplacental transmission Trichuris vulpis Dogs High/ Cecum Direct infection by ingestion of 77–84 days Fecal flotation/non- Not (whipworm) throughout embryonated eggs embryonated eggs thought the US are brownish, bipolar, to be and 80 × 30 µm zoonoticSPECIFIC and by ingestion of paratenic (transport) puppies and kittens requires a strategy toRECOMMENDATIONS hosts (Table 1). Both roundworms and eliminate parasites as they mature. BothPuppies and Kittens hookworms may undergo multisystem the Companion Animal Parasite Council Parasite control in puppies and kittens migrations in puppies and kittens. (CAPC; www.capcvet.org) and the Centerspresents several unique challenges; some Continual infection via multiple routes for Disease Control and Prevention (CDC;are the result of parasite behavior, whereas and multisystemic migration lead to the www.cdc.gov) recommend dewormingothers are the result of host factors and presence of parasites in different stages in puppies beginning at 2 weeks of age andparasiticidal efficacy. Roundworms and different organ systems during their continuing every 2 weeks through 8 weekshookworms, the most common parasites migrations. Because current parasiticides of age; thereafter, puppies can be placedof young pets, are acquired through are most effective in eliminating the adult on monthly broad-spectrum agents thatseveral routes: embryonated eggs, milk or stages of roundworms and hookworms in include heartworm and/or flea control andcolostrum, via the uterus and placenta, the intestine, control of these parasites in also possess activity against roundworms HARTZ® COMPANION ANIMALSM • SEPTEMBER 2006 • VOL. 4, NO. 3 5
  6. 6. TABLE 2: Selected Broad-Spectrum Canine and Feline Internal Parasiticides Host Species: Chemical Name Product Name Parasites Removed Dosage/Regimen Minimum Age Pyrantel ® Hartz Advanced Care™ Rid Worm™ Dog: TC, TL, AC, US 5 mg/kg No minimum age pamoate Chewable Flavored Wormer Tablets; Discretionary treatment Nemex™, Nemex™-2 (Pfizer Animal Health); many others Pyrantel Drontal® (Bayer Animal Health) Cat: Tca, AT, DC, TT 5 mg/kg praziquantel and 4 wk and >1.5 lb pamoate– 20 mg/kg pyrantel pamoate praziquantel Discretionary treatment Fenbendazole Panacur® C Canine Dewormer Dog: TC, TL, AC, US, TV 50 mg/kg/day for 3 days 6 wk (Intervet) Discretionary treatment Febantel– Drontal® Plus (Bayer Animal Health) Dog: TC, TL, AC, US, TV, 10 mg/kg febantel, 5 mg/kg 3 wk and >2 lb pyrantel DC, TP, EG, EM pyrantel pamoate, and 5 pamoate– mg/kg praziquantel praziquantel Discretionary treatment Ivermectin Heartgard® Chewables for Cats Cat: DI (L3/L4), AT, AB 24 µg/kg q30d 6 wk Ivermectin– Heartgard® Plus Chewables for Dogs; Dog: DI (L3/L4), TC, TL, AC, 6 µg/kg ivermectin and 6 wk pyrantel Iverhart™ Plus Flavored Chewables AB, US 5 mg/kg pyrantel pamoate pamoate (Virbac); Triheart® Plus Chewable q30d Tablets (Schering-Plough Animal Health) Milbemycin Interceptor® Flavor Tabs® for Dogs Cat: DI (L3/L4), Tca, AT Cat: 2.0 mg/kg q30d Cat: 6 wk or >1.5 lb oxime and Cats (Novartis) Dog: DI (L3/L4), TC, TL, AC, TV Dog: 0.5 mg/kg q30d Dog: 4 wk or >2 lb Milbemycin Sentinel® Flavor Tabs® (Novartis) Dog: DI (L3/L4), TC, TL, AC, 0.5 mg/kg milbemycin oxime 4 wk or >2 lb oxime–lufenuron TV, eggs of CF and 10 mg/kg lufenuron q30d Selamectin Revolution® (Pfizer Animal Health) Cat: DI (L3/L4), Tca, AT 6 mg/kg q30d Cat: >8 wk Dog: DI (L3/L4), CF, SS, OC, DV Dog: >6 wk AB = Ancylostoma braziliense; AC = Ancylostoma caninum; AT = Ancylostoma tubaeforme; CF = Ctenocephalides felis; DC = Dipylidium caninum; DI = Dirofilaria immitis; DV = Dermacentor variabilis; EG = Echinococcus granulosus; EM = Echinococcus multilocularis; L3 = third-stage larvae; L4 = fourth-stage larvae; OC = Otodectes cynotis; SS = Sarcoptes sca- biei; TC = Toxocara canis; Tca = Toxocara cati; TL = Toxascaris leonina; TP = Taenia pisiformis; TT = Taenia taeniaeformis; TV = Trichuris vulpis; US = Uncinaria stenocephala. and hookworms (Table 2). This monthly described for puppies. If pets are not Adult Dogs and Cats strategy serves two purposes—it helps maintained on monthly broad-spectrum Surveys indicate that dogs and improve pet owner compliance and agents, annual or semiannual fecal cats remain susceptible to parasites provides continuous roundworm and examinations using centrifugal flotation throughout their lives, although the risk hookworm control. It should be noted should be performed. Appropriate of disease diminishes somewhat as pets that only pyrantel pamoate can be used treatments should then be administered age. Adult dogs and cats are also less in puppies as young as 2 weeks; other based on results of fecal examinations likely to harbor burdens of intestinal available agents can be used in puppies (discretionary deworming). roundworms and hookworms that are and kittens starting at 3 to 4 weeks of age. It is important to remember that pets as large as is seen in puppies or kittens. If monthly broad-spectrum control are susceptible to and may harbor parasites A number of strategies have been strategies are not used, an alternative that are not eliminated by broad-spectrum employed to control parasitic infections strategy of biweekly deworming from 2 heartworm preventives. Examples include in adult pets. Among them are continual to 8 weeks of age followed by monthly tapeworms, coccidia, and Giardia. These monthly administration of broad- deworming through 6 months of age can and other parasites drive the need for spectrum heartworm preventives; annual, be employed. Because of the differences accurate fecal examinations conducted at semiannual, or quarterly use of broad- in the life cycles of canine and feline regular intervals. The frequency of spectrum dewormers; and discretionary roundworms, kittens can be treated fecal examinations (e.g., one to four deworming based on results of fecal biweekly between 3 and 9 weeks and times/year) varies based on the age of examinations. The strategy of then placed on broad-spectrum agents the pet, prior infection status, and continuous monthly use of broad- or treated monthly for 6 months as potential exposure. spectrum heartworm products is often6 HARTZ COMPANION ANIMAL ® SM • SEPTEMBER 2006 • VOL. 4, NO. 3
  7. 7. HARTZ ®IMPORTA N T NEWS FROM e nation, introdu ced k products in th ian: ing provider s of flea and tic t is registe red by the USDear Veterinar one of the lead ™ Drops for Cats. The produc retail n Corporation, ® be available in is spring, The Hartz Mountai d Hartz U ltraGuardplus er 12 weeks of age, and it willTh t calle kittens ov secticide produc use on cats anda new topical in ncy (EPA) for d l Protection Age harmful fleas an Environmenta d. protected from in the weeks ahea make sure that all pets are ent the ca re provided by stores nationally community – to ort and supplem tz® the veterinary ts that can supp their pets. Har ur goal is the same as that of effective, wel l-tested produc no flea and tic k protection on the number of O mmitted to offe ring icans use lp expand ticks. We are co illions of Amer ners and may he ely show that m ative for pet ow veterinarians . Surveys routin ec onomical altern Cats offers an us™ Drops for m ectoparasites . UltraGuardpl are protected fro companion animals that enprox, adulticide, Etof s s a well-tested l tive ingredient ula that combine -a-month topica Well-tested ac ats contains an all-new form consumers an ef fective, once ps for C t offers uardplus™ Dro ene. This produc Hartz® UltraG R), (S)-Methopr er ticks, and mosquitoes. e insecticide ow th regulator (IG as, flea eggs, de 1 insect pests . Th e feline and an insect gr ickly to kill fle food crops from treatment that works qu to protect ntly availabl ound the world in another, curre by governments ar d is an ac tive ingredient er Hartz ® feline topicals been registered pets in 2004 an one used in form Etofenprox has ation for use on icide from the first EPA registr different insect received its is a completely e use. t2. Etofenprox story of effectiv topical produc ch has a long hi other insects . 3 rin). ethoprene, whi flies, ants, and (phenoth r Cats is (S)-M , mosquitoes, plus™ Drops fo fight infestatio ns of fleas e same series tz® UltraGuard than 20 years to n underwent th The IGR in Har used for more Cats formulatio y flea (S)-Methopren e has been aGuardplus ™ Drops for uding veterinar the Hartz Ultr ® on animals, incl west acute toxi city products used the EPA’s lo A registration, required for all insecticidal rmined to be in In orde r to receive EP xicity tests n was dete ty, and acute to , the formulatio of efficacy, safe ute toxicity tests ve felines. An ts. Through the ac events in sensiti and tick produc 40 CFR 156.62 ). oduce adverse ese category (Categ ory IV - oduct can pr owners about th y insecticide pr to educate pet sages in study results, an otection is an ongoing effort important mes ith excellent flea and tick pr blicizes these u know, even w tely. Hartz pu ® As yo mitment to appropria ent of our com d tick products important elem of using flea an efforts. ians to report d the importance ebsites and other outreach e urge veterinar health issues an ochures, our w ld they occur, w a week advertising, co nsumer br pets, shou day, seven days adverse event in nsumer Relations 24 hours a e th e chance of any t Hartz ® Co eks to minimiz ners can contac While Hartz se ® ians and pet ow pport. any incident to us. Veterinar their questio ns and other su 14 for answers to at 1-800-275-14 Sincerely, , DVM Services Jill Richardson and Technical umer Relations Director, Cons 33231 l.jsp?Rec_Id=PC /Detail_Chemica et_igr.htm esticideinfo.org ents/press.asp? prm_id=568 ctsheets/factshe . http://www.p /news_ev s/ingredients/fa 1 PAN Pesticides Database w.sergeants.com pd1/biopesticide Available at ww w.epa.gov/oppbp 2 Sergeant’s news release. fact sheet. Availa ble at ww tection Agency 3 U.S. Environmental Pro
  8. 8. WOLBACHIA AND HEARTWORM DISEASE (continued from page 3) within a human pathogenic nematode. PLoS Biology Immunol Immunopathol 106(3–4):303–308, 2005. endosymbionts Wolbachia. Int J Parasitol 29: 3:e121–129, 2005. 5. Morchon R, Ferreira AC, Martin-Pacho J, et al: 357–364, 1999. 3. Taylor MJ, Cross HF, Ford L: Wolbachia bacteria Specific IgG antibody response against antigens of 7. Taylor MJ, Makunde WH, McGarry HF, et al: in filarial immunity and disease. Parasite Immunol Dirofilaria immitis and its Wolbachia endosymbiont Macrofilaricidal activity after doxycycline treatment 23:401–409, 2001. bacterium in cats with natural and experimental of Wuchereria bancrofti: A double-blind, randomised 4. Kramer LH, Tamarozzi F, Morchon R, et al: infections. Vet Parasitol 125:313–321, 2004. placebo-controlled trial. Lancet 365:2116–2121, Immune response to and tissue localization of the 6. Bandi C, McCall JW, Genchi C, et al: Effects of 2005. Wolbachia surface protein (WSP) in dogs with natural tetracycline on the filarial worms Brugia pahangi 8. Kramer L: Treating canine heartworm infection. heartworm (Dirofilaria immitis) infection. Vet and Dirofilaria immitis and their bacterial NAVC Clin Brief May:17–18, 2006.DEWORMING DEMYSTIFIED (continued from page 6)implemented in regions where of ascarids and hookworms from breeding parasiticides can then be administeredheartworm prevention is necessary for all bitches. These strategies require intense as necessary. Annual fecal examinationsor most of the year. Veterinarians must use of available parasiticides during the and discretionary use of parasiticides arestill conduct fecal examinations to assure gestation period and should be used only especially important in senior pets thatthat selected parasiticides are effectively after consulting with qualified experts. are not receiving monthly broad-spectrumcontrolling parasites. It is sometimes agents.necessary to supplement monthly broad- Senior Petsspectrum heartworm preventives with Modern parasiticides are safe and SUGGESTED READINGother control strategies using additional effective for use in older pets, including Blagburn BL: Prevalence of canine parasites based on fecal flotation. Compend Contin Educ Vet 18:483–509,parasiticides based on results of fecal those with other illnesses. In regions 1996.examinations. where heartworms remain prevalent Blagburn BL, Butler J: Optimize intestinal parasite Pregnant bitches and queens are also throughout most of the year, continuous detection with centrifugal fecal flotation. Vet Med July:455–464, 2006.more susceptible to certain parasites use of broad-spectrum agents remains Fisher M: Toxocara cati: An underestimated zoonoticduring the periparturient period. These a popular strategy. Periodic fecal agent. Trends Parasitol 19:167–170, 2003.pets should either remain on broad- examinations are necessary in senior pets Kalkofen UP: Hookworms of dogs and cats. Vet Clinspectrum preventives throughout not only because they remain susceptible North Am Small Anim Pract 7(6):1341–1354, 1987.pregnancy and lactation or they should be to parasites but also because other health Marty AM: Toxocariasis, in Meyers WM, Neafie RC, Marty AM, Wear DJ (eds): Pathology of Infectiousdewormed at the same time their offspring conditions may make them more Diseases. Washington, DC, American Registry ofare dewormed during the postparturient vulnerable to the effects of parasites. Pathology, 2000, pp 411–421.period. Veterinarians can consult with Senior pets should be examined at least Nolan TJ, Smith G: Time series analysis of the prevalence of endoparasitic infections in cats andacademic parasitologists regarding annually using a sensitive centrifugal fecal dogs presented to a veterinary teaching hospital. Vetstrategies for eliminating tissue reservoirs flotation procedure. Appropriate Parasitol 59:87–96, 1995.Veterinary Learning Systems PRST STD780 Township Line Road U.S. POSTAGEYardley, PA 19067 PAID YORK, PA PERMIT #200 402344