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Endoparasites – Ruminants

Endoparasites – Ruminants . Goals and Objectives. Understand the influence of parasitism on production Become familiar with the types of parasites afflicting agricultural animals Understand the public health implications of selected parasites Understand the basic principles of parasite

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Endoparasites – Ruminants

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  1. Endoparasites – Ruminants

  2. Goals and Objectives • Understand the influence of parasitism on production • Become familiar with the types of parasites afflicting agricultural animals • Understand the public health implications of selected parasites • Understand the basic principles of parasite control and treatment

  3. Parasitology - Ruminants • Economic Losses – Poor ADG – Abortion – Decreased conception rates – Death • Public Health – Zoonoses

  4. Reasons For Economic Losses -Producer Unaware of parasite damage estimate annual parasite-related losses to the livestock industry at more than $100 million - Timing & Frequency of treatments -Choice of dewormer -Parasites have greatest impact on high producing animals.

  5. What is ruminants Parasitism? It is a herd disease It is a production disease It develops during grazing 99% of all pastures contaminated

  6. Level of Parasitism Related To Age of animals Pasture contamination level Stocking rate of animals Grazing environment & Weather Immune status of animals

  7. Deworming strategy -Producers understand importance of internal parasite control for production efficiency. -Deworming is now standard practice on beef and dairy farms. -Must have correct product at the correct time.

  8. Definition • Types of relationships between organism and host – Commensal ‐ one benefits without harming the other – Mutualism ‐ both participants benefit – Parasitism ‐ one benefits at the expense of the other

  9. Definition • Endoparasite ‐ internal infection • Ectoparasite ‐ external infestation • Zoonotic infection ‐ transmission of an infection from animals to humans

  10. Definition • Life cycle ‐ from the start of one generation to the start of the next – Direct ‐ completion of life cycle requires a single host – Indirect ‐ completion of life cycle requires greater than one host

  11. Direct Lifecycle

  12. Indirect Lifecycle

  13. Definition • Definitive Host ‐ where sexual reproduction of parasite occurs • Intermediate Host ‐ required to complete a developmental phase in the parasites life‐cycle, excluding sexual reproduction • Pre‐patent Period ‐ time from infection of definitive host to the production of parasite offspring

  14. Designing a Program in aDairy/Meat Operation First determine the approximate level of parasitic contamination

  15. 1.- High ParasiteContamination Level Cows grazing pasture during lactation When rotational grazing is practiced

  16. 2. Moderate ParasiteContamination Level Cows grazing pasture only during dry period Cows with access to an exercise lot only (with some grass)

  17. Low ParasiteContamination Level Cows with access to dirt dry lot

  18. 4. Extremely Low ParasiteContamination Level Cows in total confinement Cows on a concrete dry lot

  19. Summary Strategy For LactatingCows Parasites have been shown to decrease milk production in early lactation Identify parasite contamination levels in each dairy operation Design deworming program based on individuals or herd treatment relative to contamination levels

  20. Parasite – Indications Purpose of the tests Direct-aids in the detection of certain protozoan trophozoites. Flotation method-eggs in feces are mixed with flotation solution that will cause them to float to the top. Baerman Funnel Technique-larva migrate to the bottom. Used to detect lungworms in ruminants. Centrifugation technique-will detect parasitic eggs when other techniques do not, specially heavier eggs that will not float. MIF (merthiolate iodine formalin) –satins and preserves protozoans & larvae

  21. Modified Wisconsin Sugar FlotationMethod Technique Samples can be stored if refrigerated Sugar solution – One pound of sugar. – Add to 12 oz(355cc) of hot water. Slides can be refrigerated for reading later Materials Sugar solution & dispensing syringe Tea strainer 3/5 oz dixie cups Tongue depressors Taper bottom 15cc tubes Test tube rack Microscope slides & 22x22 mm cover slips

  22. Modified Wisconsin Sugar FlotationMethod Add 15 - 17 cc sugar solution to sample

  23. Modified Wisconsin Sugar FlotationMethod Place 3 - 5 grams of fecal material into a 3 oz paper cup (About a thimble full)

  24. Modified Wisconsin Sugar FlotationMethod Stir solution & fecal sample to an even consistency.

  25. Modified Wisconsin Sugar FlotationMethod Stir solution & fecal sample to an even consistency.

  26. Modified Wisconsin Sugar FlotationMethod Use a tongue depressor, press as much material through strainer as possible.

  27. Modified Wisconsin Sugar FlotationMethod 1. Pour into 15cc taper bottom centrifuge tube. 2. Centrifuge in swinging arm centrifuge at 900 rpm for 5 – 7 minutes.

  28. Modified Wisconsin Sugar FlotationMethod 1. Place tube in rack and top off with sugar solution to form a meniscus. 2. Place 22x22 mm cover slip on tube and leave in place for 2 - 4 minutes.

  29. Modified Wisconsin Sugar FlotationMethod Lift cover slip upward & place on slide

  30. Modified Wisconsin Sugar FlotationMethod Use microscope to scan entire cover slip for egg count

  31. Definition • Types of parasites – Nematodes (phylum nemathelminthes)‐ round worms – Cestodes (phylum platyhelminthes) ‐ flat worms – Trematodes (phylum platyhelminthes) ‐ flukes – Protozoa (phylum protozoa) ‐ single‐celled eukaryotes

  32. Nematodes • Adult worms – male and female – range in size from large to microscopic • Eggs →Larvae (stage 1‐4) →Adult – Most have direct life cycles – Most transmitted as infective larvae on pasture • GI tract and lungs as adults

  33. GI Nematodes • ~ 11 Genera, Many Species • Sites – abomasum, small intestine, cecum, and large intestine • Most ruminants = chronic infections • Production losses and clinical disease are proportional to severity of infection

  34. GI Nematodes – Hot complex • Haemonchus contortus – 1” (25 mm) – Abomasum of small ruminants – feeds on blood – Clinical signs • anemia • death

  35. Clinical signs Haemonchus • Calf is in poor condition with ‘bottle jaw’ due to hypoproteinemia and anemia. • It is massive direct damage, usually late winter.

  36. Adults in the abomasum. Barberpole worm

  37. GI Nematodes • Ostertagia ostertagi – 1/2” (10 mm) adult worm; abomasum – most serious impact on calves – disrupt gastric acid secretion – Clinical signs • diarrhea • ill‐thrift • poor feed conversion

  38. Ostertagia ostertagi

  39. GI Nematodes • Trichostrongylus axei – “Bankrupt worm” – Adults ~1/4” (4‐8 mm); abomasum – Clinical signs • Diarrhea • dehydration • bottle jaw • emaciation

  40. Platyhelminthes (flatworms) • Hermaphroditic • Intermediate host (indirect life cycle) • Flattened appearance • Tapeworms (Cestodes) • Flukes (Trematodes)

  41. Tapeworms (cestodes) • Adult worms few inches to 15 yards long • Segmented worms with attached head (scolex) • Ruminants = intermediate host for canids and humans • Ruminants eat eggs passed in feces of canids or people

  42. Tapeworms (cestodes) • Cysts in carcass, pea‐size to grape‐size (beef measles) • People/canids infected by eating encysted beef • Carcass condemnation • ID, WA feedlots ‐ cattle infected with beef tapeworm of man (Taenia saginata); 10% losses in some feedlots

  43. Taenia saginata

  44. Liver Flukes (Trematodes) • Fasciola hepatica (most common); Fascioloides magna – Live in bile ducts as adults – Aquatic snails = intermediate host – Clinical signs • photosensitization • reduced ADG • hepatitis; clostridial dz →death – Condemned liver at slaughter • $millions in losses

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