clinical examination of farm animals

Clinical Examination of Farm Animals BY Peter G.G Jackson BVM&S, MA, DVM&S, FRCVS University of Cambridge UK & Peter D Cockcroft MA,VetMB, MSc, DCHP, DVM&S, MRCVS, University of Cambridge UK Illustrations by Samantha Elmhurst, BA Hons & Mike Pearson Blackwell Science Clinical Examination of Farm Animals BY Peter G.G Jackson BVM&S, MA, DVM&S, FRCVS University of Cambridge UK & Peter D Cockcroft MA,VetMB, MSc, DCHP, DVM&S, MRCVS, University of Cambridge UK Illustrations by Samantha Elmhurst, BA Hons & Mike Pearson Blackwell Science © 2002 by Blackwell Science Ltd, a Blackwell Publishing Company Editorial Offices: Osney Mead, Oxford OX2 0EL, UK Tel: +44 (0)1865 206206 Blackwell Science, Inc., 350 Main Street, Malden, MA 02148-5018, USA Tel: +1 781 388 8250 Iowa State Press, a Blackwell Publishing Company, 2121 State Avenue, Ames, Iowa 50014-8300, USA Tel: +1 515 292 0140 Blackwell Science Asia Pty, 54 University Street, Carlton, Victoria 3053, Australia Tel: +61 (0)3 9347 0300 Blackwell Wissenschafts Verlag, Kurfürstendamm 57, 10707 Berlin, Germany Tel: +49 (0)30 32 79 060 The right of the Author to be identified as the Author of this Work has been asserted in accordance with the Copyright, Designs and Patents Act 1988 All rights reserved No part of this publication may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, except as permitted by the UK Copyright, Designs and Patents Act 1988, without the prior permission of the publisher First published 2002 by Blackwell Science Ltd Library of Congress Cataloging-in-Publication Data Jackson, Peter G G Clinical examination of farm animals/by Peter G.G Jackson & Peter D Cockcroft p cm Includes bibliographical references (p ) ISBN 0-632-05706-8 Veterinary medicine—Diagnosis I Cockcroft, Peter D II Title SF771 J23 2002 636.089¢6075—dc21 2002023213 ISBN 0-632-05706-8 A catalogue record for this title is available from the British Library Set in 9/12 Palatino by SNP Best-set Typesetter Ltd., Hong Kong Printed and bound in Great Britain by Ashford Colour Press Ltd, Gosport, Hants For further information on Blackwell Science, visit our website: www.blackwell-science.com Contents Preface, v 11 Clinical Examination of the Male Genital System, 141 12 Clinical Examination of the Udder, 154 13 Clinical Examination of the Musculoskeletal System, 167 14 Clinical Examination of the Nervous System, 198 Acknowledgements, vi Part I Introduction, 1 Principles of Clinical Examination, Part II Cattle – Clinical Examination by Body System and Region, The General Clinical Examination of Cattle, Clinical Examination of the Lymphatic System, 12 Clinical Examination of the Skin, 16 Clinical Examination of the Head and Neck, 29 Part III Sheep, 217 15 Clinical Examination of the Sheep, 219 Part IV Pigs, 249 16 Clinical Examination of the Cardiovascular System, 51 Clinical Examination of the Respiratory System, 65 Clinical Examination of the Pig, 251 Part V Goats, 279 17 Clinical Examination of the Goat, 281 Bibliography, 300 10 Clinical Examination of the Gastrointestinal System, 81 Clinical Examination of the Urinary System, 113 Clinical Examination of the Female Genital System, 125 Appendix Normal Physiological Values, 301 Appendix Laboratory Reference Values: Haematology, 302 Appendix Laboratory Reference Values: Biochemistry, 303 Index, 306 iii This book is dedicated to our families Preface More mistakes are made by not looking than by not knowing Anon Clinical examination is a fundamental part of the process of veterinary diagnosis It provides the veterinarian with the information required to determine the disease or diseases producing the clinical abnormalities In addition, the information derived from the clinical examination should assist the veterinarian in determining the severity of the pathophysiological processes present Without a proficient clinical examination and an accurate diagnosis it is unlikely that the treatment, control, prognosis and welfare of animals will be optimised The purpose of this book is to assist clinicians in performing a detailed clinical examination of the individual animal and to increase the awareness of more advanced techniques used in further investigations The structure and content of the book should assist veterinary students in their understanding of farm animal clinical examination, act as a quick reference for clinicians who are called upon to examine an unfamiliar species and provide a more detailed account for experienced clinicians in their continuing professional development In this book the authors have attempted to describe and illustrate the ways in which clinical exam- ination of farm animal species can be performed Throughout the book conditions are used to illustrate the predisposing risk factors and the clinical abnormalities that may be present In doing so the authors have tried to provide information that may assist the reader in formulating differential diagnoses Numerous illustrations are provided to complement the text In the first part of the book the principles of clinical examination are described The second and largest part of the book is devoted to the clinical examination of cattle Following a chapter on the general examination of cattle, each body system or region has a chapter in which the applied anatomy is briefly reviewed and the clinical examination is described in detail Within each of these chapters there are checklists on how to perform the examination and what abnormalities may be present Further parts of the book are devoted to the clinical examination of sheep, goats and pigs Where the examination of the ovine, caprine or porcine body system is similar to the bovine, the reader is referred back to the appropriate cattle chapter The book is largely based on the experience of the authors as practitioners, as consultants in referral clinics and as teachers of clinical veterinary students The authors hope that the reader will find this book both interesting and useful v Acknowledgements The authors would like to thank the graphic artists for the illustrations in this book The pictures in Chapters and were drawn by Mike Pearson The front cover and the other pictures in the book were vi drawn by Samantha Elmhurst The authors would also like to acknowledge Antonia Seymour of Blackwell Publishing for her support and guidance during the writing of this book Part I Introduction Clinical Examination of the Goat lumbosacral space are useful in some cases Clinical signs of a number of important caprine neurological conditions are given below Floppy kid syndrome This affects kids in the first 10 days of life Affected kids are normal at birth, but suddenly show severe muscle weakness, marginal consciousness and reduced reflex response One kid only in a litter may be affected There is no evidence of septicaemia, diarrhoea, pneumonia or colostral deficiency The condition is thought to be the result of a metabolic acidosis non-specific They include a slight change in temperament, weight loss and reduced milk yield Later, more specific signs of pruritus and neurological changes are seen Affected goats may nibble or scratch any accessible part of the skin, often causing quite severe damage Stimulation of the skin caudal to the sacrum may cause the animal to make nibbling movements with its jaws and sometimes salivate Neurological signs include incoordination and a high stepping gait Muscular tremors are also seen The animal may be dull or hyperaesthetic and temperament changes become more pronounced Caprine arthritis encephalitis virus Encephalitis can occur in both young and adult goats In kids, the neurological signs are those of an ascending infection of the spinal cord The patient may be initially bright but pyrexic Within a few days the kid may show signs of ataxia, hemiplegia or tetraplegia and blindness Terminal recumbency and coma follow In adult goats, CAEV encephalitis may follow other manifestations of the disease including arthritis, pneumonia or mastitis The animal may show incoordination of the limbs followed by paralysis Swayback in kids The congenital form of the disease is uncommon in kids Delayed swayback is seen in older kids which are normal at birth Progressive hind-limb ataxia caused by copper deficiency induced demyelination is seen, although the kid appears bright and willing to eat Blood copper levels are usually low in affected kids and in their dams The latter may show other subtle signs of copper deficiency including anaemia, diarrhoea and hair discolouration Scrapie This is seen chiefly in animals in the to year old age group Initial signs may be subtle and C LINICIAN ’ S C HECKLIST – C LINICAL E XAMINATION OF THE G OAT Owner’s complaint History of the patient – long and short term Signalment – breed, age, sex of the goat or goats The goat environment – observation and inspection Observation of the goat or group of goats Clinical examination of the patient Temperature, pulse and respiration Mucous membranes, capillary refill time Palpation of the carcase lymph nodes Head and neck Cardiovascular system Respiratory system Gastrointestinal system Udder and perineum External genital system of the female External genital system of the male Locomotor system Neurological examination Clinical pathology Post-mortem examination if required 299 Bibliography Andrews, A.H (2000) The Health of Dairy Cattle Blackwell Science, Oxford Arthur, G.H., Noakes, D.E., Pearson, H & Parkinson, T.J (1996) Veterinary Reproduction and Obstetrics, 7th edn W.B Saunders, London Baker, J.C (1987) Bovine Neurologic Diseases, Veterinary Clinics of North America, Food Animal Practice, Vol 3.1 W.B Saunders, Philadelphia Brightling, P (1995) The Examination of a Sick Cow Proceedings No 78, Postgraduate Committee in Veterinary Science, University of Sydney Clarkson, M.J & Winter, A.C (1997) A Handbook for the Sheep Clinician, 2nd edn Liverpool University Press Greenough, P.R & Weaver, A.D (1997) Lameness in Cattle, 3rd edn W.B Saunders, Philadelphia Jackson, P.G.G (1995) Handbook of Veterinary Obstetrics W.B Saunders, London Martin, W.B & Aitken, I.D (2000) Diseases of Sheep, 3rd edn Blackwell Science, Oxford Matthews, J (1999) Diseases of the Goat, 2nd edn Blackwell Science, Oxford 300 Meredith, M.J (1995) Animal Breeding and Infertility Blackwell Science, Oxford Radostits, O.M., Gay, C.C., Blood D.C & Hinchcliff, K.W (2000) Veterinary Medicine, 9th edn W.B Saunders, London Radostits, O.M., Mayhew, I.G.J & Houston, D.M (2000) Veterinary Clinical Examination and Diagnosis W.B Saunders, London Rosenberger, G (1979) Clinical Examination of Cattle Verlag Paul Parey, Berlin Searman, D.M & Robinson, R.A (1983) Clinical Examination of Sheep and Goats, Veterinary Clinics of North America, Large Animal Practice Vol 5.3 W.B Saunders, Philadelphia Taylor, D.J (1999) Pig Diseases, 7th edn Glasgow (published by the author) Wilson, J.H (1992) Physical Examination, Veterinary Clinics of North America, Food Animal Practice, Vol 8.2 W.B Saunders, Philadelphia Appendix Normal Physiological Values Cattle Temperature (°C) Normal range Average Resting pulse rate (beats/min) Normal range Average Resting respiration rate (breaths/min) Average Oestrus cycle (days) Range Average Gestation (days) Range Average Temperature (°C) Range Average Resting pulse rate (beats/min) Range Average Resting respiration rate (breaths/min) Range Average Sheep Goats Pigs 38.0–39.0 38.5 38.5–40.0 39.0 39.0–40.5 39.5 60–80 70 15–30 20 70–90 75 20–30 25 70–100 90 15–30 30 90–110 100 10–20 15 18–24 21 14–19 17 18–21 20 18–24 21 279–291 283 140–160 150 145–155 150 110–116 114 Calves Lambs Kids Piglets 38.5–39.5 39.0 39.0–40.0 39.5 38.8–40.2 39.5 38.5–40.0 39.0 39.0–39.5 39.5 80–120 100 80–100 85 100–120 105 200–220 210 24–36 30 36–48 40 20–40 30 24–36 30 301 Appendix Laboratory Reference Values: Haematology The haematological values for cattle, sheep, goats and pigs are reproduced with permission from Radostits, O.M., Gay, C.C., Blood, D.C and Hinchcliff, K.W (2000) Veterinary Medicine, 9th edn, W.B Saunders, London, pp 1819–1822 Reference ranges supplied by individual laboratories should be consulted when interpreting results from these laboratories Table A2.1 Haematology – Conventional units Haemoglobin (g/dL) Haematocrit (packed cell volume) (%) RBC (¥106/mL) MCV (fL) MCH (pg) MCHC (g/dL) Thrombocytes (¥103/mL) WBC (per/mL) Neutrophils (mature) (per/mL) Neutrophils (band cells) (per/mL) Lymphocytes (per/mL) Monocytes (per/mL) Eosinophils (per/mL) Fibrinogen (mg/dL) Cattle Sheep Goats Pigs 8.0–15.0 24.0–46.0 5.0–10.0 40.0–60.0 11.0–17.0 30.0–36.0 100–800 4000–12 000 600–4000 0–120 2500–7500 25–840 0–2400 200–700 9.0–15.0 27.0–45.0 9.0–15.0 28.0–40.0 8.0–12.0 31.0–34.0 250–750 4000–12 000 700–6000 Rare 2000–9000 0–750 0–1000 200–500 8.0–12.0 22.0–38.0 8.0–18.0 16.0–25.0 5.2–8.0 30.0–36.0 300–600 4000–13 000 1200–7200 Rare 2000–9000 0–550 0–650 200–300 10.0–16.0 32.0–50.0 5.0–8.0 50.0–68.0 17.0–21.0 30.0–34.0 320–520 11 000–22 000 080–10 450 0–880 290–13 640 200–2200 55–2420 Table A2.2 Haematology – International System of Units (SI) Haemoglobin (g/L) Haematocrit (packed cell volume) (L/L) RBC (¥1012/L) MCV (fL) MCH (pg) MCHC (g/L) Thrombocytes (¥109/L) WBC (¥109/L) Neutrophils (mature) (¥109/L) Neutrophils (band cells) (¥109/L) Lymphocytes (¥109/L) Monocytes (¥109/L) Eosinophils (¥109/L) Fibrinogen (g/L) 302 Cattle Sheep Goats Pigs 80–150 0.24–0.46 5.0–10.00 40–60 11.0–17.0 300–360 100–800 4.0–12.0 0.6–4.0 0–0.1 2.0–7.5 0–0.8 0–2.4 2–7 90–150 0.27–0.45 8.0–18.0 28–40 8.0–12.0 310–340 250–750 4.0–12.0 0.7–6.0 Rare 2.0–9.0 0–0.8 0–1.0 2–5 80–120 0.22–0.38 5.0–8.0 16–25 5.2–8.0 300–360 300–600 4.0–13.0 1.2–7.2 Rare 2.0–9.0 0–0.6 0–0.7 2–3 100–160 0.32–0.50 6.8–12.9 50–68 17.0–21.0 303–340 320–520 11.0–22.0 3.1–10.5 0–0.1 4.3–13.0 0.2–2.2 0.05–2.4 Appendix Laboratory Reference Values: Biochemistry The biochemical values for cattle, sheep and pigs are reproduced with permission from Radostits, O.M., Gay, C.C., Blood, D.C and Hinchcliff, K.W (2000) Veterinary Medicine, 9th edn, W.B Saunders, London, pp 1819–1822 The biochemical values for goats are reproduced with permission from Matthews, J (1999) Diseases of the Goat, Blackwell Science, Oxford, p 332 Reference ranges supplied by individual laboratories should be consulted when interpreting results from these laboratories Table A3.1 Serum constituents (conventional units) Electrolytes Sodium (mEq/L) Potassium (mEq/L) Chloride (mEq/L) Osmolality (mOsmol/kg) Acid : base status pH (venous) PCO2 (venous) (mmHg) Bicarbonate (mEq/L) Total carbon dioxide (mEq/L) Anion gap (mEq/L) Minerals Calcium, total (mg/dL) Calcium, ionised (mg/dL) Phosphorus (mg/dL) Magnesium (mg/dL) Iron (mg/dL) Iron binding capacity (mg/dL) Renal function Urea nitrogen (mg/dL) Creatinine (mg/dL) Liver function Total bilirubin (mg/dL) Direct (conjugated) bilirubin (mg/dL) Bile acids (mg/mL) Metabolites Ammonia (mg/dL) Cholesterol (mg/dL) Free fatty acids (mg/L) Glucose (mg/dL) Cattle Sheep Pigs Goats 132–152 3.9–5.8 95–110 270–306 145–152 3.9–5.4 95–103 140–150 4.7–7.1 95–103 135–156 3.4–6.1 98–110 7.35–7.50 34–45 20–30 20–30 14–26 7.32–7.50 38–45 21–28 20–28 12–24 18–27 17–26 10–25 9.7–12.4 4.8–6.2 5.6–6.5 1.8–2.3 57–162 110–350 11.5–13.0 5.7–6.5 5.0–7.3 2.2–2.8 166–222 7.1–11.6 3.5–5.8 5.3–9.6 1.1–1.5 73–140 270–557 9.2–11.6 6–27 1–2 10–35 1.2–1.9 10–30 1.0–2.7 12–26 0.6–1.6 0.01–0.5 0.04–0.44