• Large Animal Parasitology Procedures for Veterinary Technicians

    Comprehensive illustrated reference on parasitic nematodes, cestodes, coccidian oocysts and trematode egg recoveries, identification, and enumeration with treatment strategies for five separate categories of animal patients

    Large Animal Parasitology Procedures for Veterinary Technicians illustrates, in detail, the most sensitive diagnostic procedure for internal parasites of domestic animals using the Modified Wisconsin Sugar Flotation Method. With step-by-step pictures and bullet-point instructions, this text discusses sample collection and storage techniques, as well as the strengths and weaknesses inherent to other commonly used tests. Potential sources for infection, the seasonality of the infection, possible environmental recontamination, and control strategies are all covered in detail, with suggestions to prevent reoccurrences.

    Parasites of the equine, large and small ruminants (including alpaca), swine, poultry and hoofed wildlife patients are included, with full color images for quick identification, an assessment of life cycle stage, and discussion of zoonotic potential. Each species section is heavily illustrated with comparative images to aid the technician in quickly identifying the parasite and life cycle stage.

    In Large Animal Parasitology Procedures for Veterinary Technicians, readers can find information on:

    • The definition and economic importance of parasitisms, details on the epidemiology of parasitic enteritis, including basics of protozoology, helminthology, and overall applied veterinary parasitology
    • Sample collection and shipment of specimens, including collection, storage, examinations, and interpretations
    • Fecal examination using the Modified Wisconsin Sugar Flotation method, compared with gross examination, smear, sedimentation, and other flotation techniques, plus a fluke egg recovery technique and the Baermann technique for lungworm larvae recovery
    • Internal parasite diagnosis and worm egg recoveries, descriptions and pictures of nematode parasite eggs (as well as coccidia oocysts), plus tapeworm eggs and fluke egg descriptions and photos for a variety of host animals

    Illustrating commonly used diagnostic tests in veterinary parasitology, with step-by-step instructions for accuracy, Large Animal Parasitology Procedures for Veterinary Technicians is an essential reference for veterinary technicians and veterinary technician students dealing with domestic animals, including horses, ruminants, swine, poultry, and hoofed wildlife.

  • Preface xv

    1 Introduction to Large Animal Parasitology Procedures for Veterinary Technicians 1

    Gastrointestinal Parasitism Can be Categorized into Four Distinct Periods of Development 22

    Early Larvae Development and Translation Period 22

    The Ingestion and Infective Prepatent Period 30

    The Inhibition or Arrested Development Phase 31

    The Patent Period 35

    References 57

    2 The Modified Wisconsin Sugar Flotation Method 59

    Standard Operating Procedure for the “Modified Wisconsin Sugar Flotation Technique” 82

    Interpretation of Fecal Worm Egg Counts in Sheep, Goats, and Camelids Using the Modified Wisconsin Sugar Flotation Technique 88

    Quick Assessment for Sheep, Goats, and Camelids Based on Fecal Worm Egg Counts 97

    References 106

    3 Parasites in Beef Cattle 107

    Strategic Deworming Entails More than Simply Applying a Dewormer 115

    The Economics of an Aggressive Deworming Program 115

    Interpretation of Fecal Worm Egg Counts in Cattle Using “The Modified Wisconsin Sugar Flotation Technique” 133

    Fecal Egg Count Reduction Test (FECRT) 137

    Product Profile of Fenbendazole (Safe-Guard®/Panacur® – Merck Animal Health) 137

    Treatment Timing 142

    Gastrointestinal and Lungworm Parasites Found in Beef Cattle 142

    Stomach (Abomasal) Worms 142

    Intestinal Nematode Parasites 142

    Intestinal Cestode Parasites (Cattle Tapeworms) 158

    Cattle Lungworm (Dictyocaulus viviparous) 158

    Trematodes Parasites (Liver Flukes) 161

    Protozoan Parasites of Cattle 162

    References 167

    4 Parasites in Dairy Cattle 171

    Detection is Foremost in the Economic Analysis 171

    Gastrointestinal and Lung Parasite Infections Found in Dairy Cattle (See Figure 4.8) 175

    Stomach Worms 175

    Intestinal Nematode Parasites 177

    Intestinal Cestode Parasites (Cattle Tapeworms) 183

    Cattle Lungworm (Dictyocaulus Viviparous) 185

    Trematodes Parasites (Liver Flukes) 185

    Protozoan Parasites of Cattle 185

    Risk Factors and Production Losses Caused by Gastrointestinal Parasitism 188

    How Many Parasites are Needed to Cause Clinical Disease? 188

    Level of Efficiency Can Affect Production Losses 189

    Variation in Parasites Numbers and Levels of Contamination Rates Exists 190

    Age and Management Variations Affect Parasite Buildup in Animals 191

    Understanding How Gastrointestinal Parasites Affect Lactating Dairy Cows 191

    Monitoring Dairy Herds for Gastrointestinal Parasite Infections 192

    Every Herd is Different when it Comes to Internal Parasitic Infections 192

    The Following are Guidelines to Determine Parasite Exposure of a Dairy Herd Based on Animal Management 192

    Obtaining a Comprehensive “Parasite Fecal Check” of the Herd Can be Important 193

    Production Losses Due to Gastrointestinal Parasites 193

    Seasonal Control of Gastrointestinal Parasitic Infections in Dairy Operations 193

    Conclusion 197

    References 198

    5 Parasites in Equine 199

    Gastrointestinal Nematode Parasites Affect Horses in Many Ways 200

    Parasites Develop Differently in Horses than in Cattle 202

    Parasite Resistance to Dewormers has Become a Major Problem 206

    The Seasonal Transmission of Parasites in the Horse 208

    Seasonal Control of Parasites in Horses Can be Achieved by Reducing Parasite Contamination from the Environment 211

    General Recommendations for Strategic Timed Deworming for the Season Control of Gastrointestinal Parasites in Horses 212

    A Two-Year Study Demonstrating the Value of Strategic Deworming to Reduce Environment Contamination was Conducted in Nevada 213

    Equine Dewormers 217

    Fecal Monitoring is the Best Way to Determine Whether Treatment is Effective 218

    The Major Gastrointestinal Nematode Parasites of Horses are 219

    Other Notable Internal Parasites of the Horse 219

    Review of Internal Nematode Parasite of Horses 219

    Other Parasites 228

    Guide for Interpretation of Fecal Worm Egg Counts in Horses Using “The Modified Wisconsin Sugar Flotation Technique” 231

    Quick Assessment for Equine Based on Fecal Worm Egg Counts 231

    Inhibited Small Strongyles Cause Problems with Worm Egg Count Interpretations 231

    References 232

    6 Parasites of Swine 235

    Large Roundworms (Ascaris suum) 241

    Background 241

    Diagnosis in Lungs 243

    Diagnosis in Liver 245

    Diagnosis in the Feces 245

    Whipworms (Trichuris suis) 247

    Background 247

    Diagnosis in the Cecum 247

    Diagnosis in the Feces 250

    Threadworms (Strongyloides ramsoni) 252

    Background 252

    Diagnosis in the Feces 252

    Treatment Guidelines 253

    Nodular Worms (Oesophagostomum dentatum) 253

    Background 253

    Diagnosis in the Large Intestine 254

    Diagnosis in the Feces 255

    Treatment Guidelines 257

    The Development and Buildup of Parasitism within a Swine Operation Depends on Many Factors 257

    Materials and Methods for Fecal Sampling 258

    Specific Sample Instructions 258

    Fecal Worm Egg Count Interpretation and Whole Herd Deworming Guidelines 259

    Treatment to Control Parasitism and Reduce Parasite Future Contamination in a Facility 260

    Developing Parasite Data for Swine Clients 261

    References 261

    7 Parasites in Small Ruminants 263

    Strategic Deworming for Small Ruminants 278

    Phase I: “0–3–6–9” Spring Dewormings 278

    Phase II – Fall Cleanup Deworming 280

    Summary 280

    Fecal Monitoring is the Best Way to Determine Whether Treatment is Effective 280

    Interpretation of Fecal Worm Egg Counts in Small Ruminants Using the Modified Wisconsin Sugar Flotation Technique 284

    Quick Assessment for Sheep, Goats, and Camelids Based on Fecal Worm Egg Counts 284

    Gastrointestinal and Lung Parasite Infections Found in Small Ruminants 285

    Stomach Worms 286

    Intestinal Nematode Parasites 288

    Intestinal Cestode (Tapeworm) Parasites (Moniezia expansa and Moniezia benedeni) 300

    Trematodes Parasites (Liver Flukes) 300

    Protozoan Parasites of Small Ruminants 304

    References 307

    8 Parasites of Hoofed Wildlife 309

    Gastrointestinal Nematode Parasites are Important to Wildlife 313

    Parasite Life Cycles 313

    Transmission of Parasites 313

    Control of Parasites in the Wild 314

    Dewormer for Hoofed Wildlife 314

    Description and Dosage Rate 317

    Estimating Herd Size and Required Dose 317

    Strategic Wildlife Deworming Program 317

    The Modified Wisconsin Sugar Fecal Exam (see Figure 8.11) Plus a Submission Form (See Figure 8.12) and a Picture of the Most Common Eggs Found with Hoofed Wildlife Fecal Samples (See Figure 8.13) 318

    Interpretation of Fecal Worm Egg Counts in Hoofed Wildlife Using the Modified Wisconsin Sugar Flotation Technique 318

    Quick Assessment for Hoofed Wildlife Based on Fecal Worm Egg Counts 320

    Gastrointestinal and Lung Parasite Infections Found in Small Ruminants and Hoofed Wildlife 321

    Stomach Worms 321

    Intestinal Parasites 324

    References 333

    Index 335

  • Donald H. Bliss, PhD (Veterinary Parasitologist), owns and operates a parasite diagnostic laboratory (MidAmerica Ag Research) in Verona, Wisconsin, USA.

Veterinary Clinics of North America
info