Joe Camp Professor of Veterinary Parasitology Purdue University College of Veterinary Medicine

1. Joe Camp Professor of Veterinary Parasitology Purdue University College of Veterinary Medicine

2. Nematodes

3. Vary in size from microscopic to the vary large (> 1m). • Elongate, worm-like, and taper at both ends. • Numerous surface modifications exist, such as; alae, ridges, warts, anterior bulb, or shield-like collar around mouth.

4. Nematodes undergo incremental growth punctuated by molts of the cuticle. Usually 4 larval stages and variations among parasites as to which is the infective stage. Egg Adult(L5) L1 L4 L2 L3 Generic Life Cycle

5. Ascarids

6. Toxocara canis • Found in dogs and wild canids. • ZOONOTIC disease (VLM and OLM) • Transmission to canines during life cycle occurs by several methods: • Direct • Transplacental* • Transmammary • Paratenic Host

7. Toxocara canis

8. Clinical Disease: Dull hair coat, abdominal distention (pot belly), poor appetite, loose stool, intestinal obstruction, pneumonia

9. Intestinal obstruction

10. Intestinal Obstruction

11. Subspherical Yellow-brown One cell stage takes up most of the egg. Egg description 72 - 91 m X 63 - 79 m Thick shell, coarsely pitted Coarse pitting

12. coarse pitting of T. canis

13. video of coarse pitting of T. canis

14. Toxocara cati • Found in cats. • Also, ZOONOTIC. • Similar transmission methods to Toxocara canis, except: • No transplacental transmission • No transmammary transmission in naturally infected queens • Similar clinical disease as Toxocara canis.

15. Fine pitting Egg description • Similar to T. canis except smaller (64 - 88 m X 53 - 73 m). • Finely pitted surface.

16. T. canis and T. cati comparison

17. video of fine pitting of T. cati

18. Toxascaris leonina • Dogs, cats, foxes, wolves. • Life cycle uses: • Direct Transmission • Paratenic Host Transmission • Eggs develop very quickly in the environment (3-6 days). • Clinical disease rarely observed.

19. Lipid fibrils Egg description • 75-85 X 60-75 m • Colorless • Oval with a smooth, thick shell • Fine fibrils (lipid layer) on inside of shell

20. Toxocara canis and Toxascaris leonina

21. T. cati T. canis T. leonina

22. Baylisascaris procyonis • Raccoons; sometimes dogs. • ZOONOTIC!!!! • Direct development in small intestine of adults (no migration). • Transmission methods: • Direct (Juveniles) • Paratenic Hosts (Adults) • Generally, no clinical signs of disease in raccoons.

24. Golden brown • Thick shell with finely granular surface. Egg description • 63-88 X 53-68 m • Ellipsoidal

26. Important Points to Remember • Has affected over 100 species of animals, including humans. • Eggs infective within 30 days of being passed in feces. • Pet raccoons or those kept in confinement pose an increased risk of exposure due to concentration of feces and eggs in an area. • Raccoons usually do not show clinical signs. • Must perform routine fecal examinations and periodic deworming to reduce parasite contamination. • Do not use raccoon enclosures for other animals unless they have been decontaminated. • Avoid all contaminated areas unless treated.

27. Larva Migrans • Visceral Larva Migrans (VLM) • Larvae migrating through liver and lungs resulting in fever, hepatomegaly, pneumonia, etc. • Ocular Larva Migrans (OLM) • Unilateral ocular disease • Neural Larva Migrans (NLM) • Migration of larvae and larval growth in the brain and spinal cord.

29. Ascarid Treatment • Approved products for dogs (T. canis and T. leonina) • Milbemycin oxime • Moxidectin • Pyrantel pamoate • Fenbendazole • Piperazine (may have lower efficacy) • Monthly heartworm preventives • Milbemycin oxime or ivermectin plus pyrantel • Febantel in combination with pyrantel and praziquantel • Pyrantel in combination with ivermectin and praziquantel

30. Ascarid Treatment • Arrested larvae difficult to kill with current anthelmintics. • Perform strategic deworming protocols (CAPC Guidelines) to prevent transplacental and transmammary transmission. • Must also treat bitch since she may re-infect herself by ingesting infective larvae from pup’s feces.

31. Ascarid Treatment • Approved products for cats (T. cati and T. leonina) • Milbemycin oxime • Moxidectin • Pyrantel pamoate • Fenbendazole • Piperazine (may have lower efficacy) • Selamectin (T. cationly) • Emodepside (T. cati only)

32. Ascarid Treatment • Baylisascaris procyonis • Most of the products that remove adult Toxocara canis from dogs will remove adult B. procyonis although no products are approved for that specific use.

33. Small Animal Parasite Control • Ascarid eggs are resistant to most environmental conditions and will remain infective for many, many years. • Steps to “clean up” environment include: • Entomb with concrete or remove top 6 inches of soil. • Kennels thoroughly cleaned of organic debris. • Decontaminate with 1% bleach solution (will not kill eggs). • Hot, boiling water to spot clean. • Flaming with propane torch.

34. Ascarid Prepatent Periods • T. canis • Direct transmission, pups < 3 mos. of age; tracheal migration- 4 – 5 weeks • Transplacental transmission, following tracheal migration- 3 – 4 weeks after pup is born • Transmammary transmission- 2 – 3 weeks after pup is born • Paratenic host transmission- 2 – 3 weeks • T. cati • Direct transmission- ~ 8 weeks • Paratenic host transmission- ~ 3 weeks • T. leonina • Direct transmission- ~ 10.5 weeks • B. procyonis • Direct transmission in young raccoons- 50 – 76 days • Paratenic host transmission in adult raccoons- 32 – 38 days

35. We would like to acknowledge Elanco for their sponsorship in support of course development.