Blackwell's 5 Minute Veterinary Consult - Ruminant. 1. CONTENTS PRE FA CE A CKNO WLEDGMEN T S CONS UL TING EDITORS CONTRIBUTORS ABOMASAL EMPTYYNG DEFECT (AED) IN SHEEP AB OMASAL IMPA C T I ON ABOMASAL UL CERS ABORTION ABORTION: BACTERIAL ABORTION: FARMED CER VIDAE. BLACKWELL’S FIVE-MINUTE VETERINARY CONSULT RUMINANT Scott RR. Haskell, DVM, MPVM, PhD Editor. Edition first published 2008 © 2008 Wiley-Blackwell Blackwell Publishing was acquired by John Wiley & Sons in February 2007.
Blaclcwell’s publishing program has been merged with W1ley’s global Scientific, Technical, and Medical business to form Wiley—Blaclcwell. Editorial Office 2121 State Avenue, Ames, Iowa, USA For details of our global editorial oflices, for customer services, and for information about how to apply for permission to reuse the copyright material in this book, please see our website at www. Com'wilev-blackwell Authorization to photocopy items for internal or personal use, or the internal or personal use of specific clients, is granted by Blackwell provided that the base fee is paid directly to the Copyright Clearance Center, 222 Rosewood Drive, Danvers, MA 01923. For those organizations that have been ganted a photocopy license by CCC, a separate system of payments has been arranged The fee codes for users of the Transactional Reporting Service are ISBN-13: 978—0—78 l7—5325—8«’2008. Designations used by companies to their products are ofien claimed as trademarks. All brand names and product names used in this book are trade names, service marks, trademarks or registered trademarks of their respective owners.
The publisher is not associated with any product or vendor mentioned in this book. This publication is designed to provide accurate and authoritative information in regard to the subject matter covered It is sold on the understanding that the publisher is not engaged in rendering professional services. Lfprofessional advice or other expert assistance is required, the services of a competent professional should be sought. Library of Congress Cataloghg-in-Publication Data Blaclcwelfs five-mimite veterinary consult. Ruminant / edited by Scott RR.
P 3 591 Includes bibliogaphical references and index. ISBN-13: 978-0-7817-5325-8 (alk. Paper) ISBN-10: 0-7817-5325-2 (alk.
Ruminants—Diseases—-Handbooks, manuals, etc. R (Scott R R.
Title: Five-minute veterinary consult. Tifle: Ruminant.
Animal Diseases—Handbooks. Veterinary Medicinrtnethods-Handbooks. SF 997.5.U5 B632 2008 SF997.5.R86B532 2008 636.2'089—dc812. To Dr. Bernard 'Bernie' Feldman, deceased Professor at Virginia Tech: mentor, friend brilliant professor, and scholar.
Bernie, your support in times of need to so many can never be repaid. You still remain my professional light.
Thank you To Dr. Charles 'Charlie' Hjeipe, Professor Emeritus at the University of California, Davis; feedlot antibiotic pioneer, mentor, gifted diagnostician, and friend. Charlie, you taught many of us through the years much more than bovine practice. Thank you To Bette and Charles Haskell, in memory of my loving parents who taught me perseverance, compassion, and fortitude. Thank you To Parlin Gale, my sister who consistently shows me warmth, intelligence, and support administered with humor. Thank you for your guidance on the journey.
To Annie, Sydney, and Lilly Haskell, my kindred spirits. You taught me compassion, unwavering devotion. Thank you. PREFACE Keeping current is a diflicult task for today’s ruminant veterinary practitioner.
The ability to stay current through veterinary literature and research is a daunting if not seemingly impossible task. Many of the research results and conclusions in the scientific literature are confusing and may be inconclusive to today’s food animal practitioner.
Blackwell ’s F ive-lilinute Veterinary Consult: Ruminant is designed to provide to the practicing veterinariaiL veterinary student, animal scientist, extension specialist, and researcher a quick, concise, and practical review of many if not most of the important diseases and clinical problems facing ruminants and pseudoruminants in the new millennium. Our goal in creating this textbook in the Five—Minute format is to provide up—to—date information in an easy—to—use format. Emphasis has been placed on the diagnosis and treatment of problems and diseases commonly seen by the ruminant veterinarian. Todayis ruminant practitioners provide services that are not always taught at veterinary colleges. As reproductive specialists, they are asked to conduct breeding soundness examinations and give extensive reproductive support programs. Genetic evaluation and the selection of dams and sires are increasing in their importance.
Vaccination and deworming program implementation and evaluation are daily encounters for the practicing veterinarian Nutritional support and body condition scoring as well as foot care have become necessary tools for the competent practitioner. And finally, financial recommendations are becoming a common purview in ruminant practice.
This text addresses these issues as well as leads the reader to suggested readings. Several good internal medicine and production medicine textbooks are available. The uniqueness and importance of Blackwell ’s F ive—. Minute Veterinary Consult. ‘ Ruminant are in its use as a quick reference guide. Though this textbook is a treatise of ruminant production and diseases, camelids have been included due to their growing importance in domestic andinternational agriculture. Though camelids are technically pseudoruminants, their physiology and disease patterns are similar in many ways to true ruminants.
The inclusion of selected camelid diseases here as a quick reference is important for the practicing veterinarian. Nondomesticated and semidomesticated ruminant species are more commonly found in farming situations worldwide. Practitioners have little time to literature search the management and care of these species. In many cases, the information has not been readily available until this textbook. Research demands on practitioners have been increasing. Many practitioners now are called upon to design and implement field trials, on-farm vaccination evaluation programs, and independent epidemiologic evaluations as a necessary part of the busy practice. Environmental issues will become the primary to animal agriculture in many areas of the wodd in this millermium.
Sections in this textbook alert the reader to important and practical considerations to the environmental concerns faced by animal agriculture today. Sustainability of animal agriculture for the future is being compromised Emerging disease issues are also covered in the textbook. Today’s events in agicultural biosecurity and disease introduction are an component inveterinary medicine. Private practitioners are the frontline of defense and first responders in the protection against a large—scale disease outbreak. I, the consulting editors, and the contributors are delighted privileged and honored to have been able to present this textbook. Over two hundred veterinary specialists have contributed An expert wrote each chapter on the specified subject matter. I am indebted to the many contributors and the consulting editors, whose dfligence and hard work.
ACKNOWLEDGMENTS I would like to t: hank the consulting editors and the contributors who by t: heir knowledge and professional expertise have enhanced the quality of these writings. Without their exceptional writing capabilities and understandings of ruminant production medicine, this textbook would iii no way reflect flare and topical issues.
Their suggestions, input, and commitment made this text an exceptional diagiostic tool. Danelle Bickett-W'edd e gave generously of her time and professional expertise in the foundation and proyess to this text. Many thanks go to her and her tireless editing elforts. CONS UL TING EDITORS DANELLE BICKETDWEDDLE, DVM, MPH Dipl.
ACVPM Section Editor—Dairy Center for Food Security and Public Health Iowa State University Ames, IA 50011 TERRY W. LEHEN'BAUER DVM, IVIPVM, PhD, Dipl ACVPM Department of Veterinary Pathobiology College of Veterinary Medicine Oklahoma State University Strllwater, OK DAVID MCKENZIE, DVM, PhD, Dipl. ACVLVI School of Veterinary Medicine Tuskegee Institute Tuskegee, AL 36088. CONTRIBUTORS JOHN ADASKA CAI-IF S School of Veterinary Medicine University of California Davis, CA 956 16 DANA ALLEN Department of Animal Science University of Minnesota St. MN 55108 YESSENIA ALMEDIA UT College of Veterinary Medicine Dept.
Of Large Animal Clinical Sciences Knoxville, TN FREDERIC TRIPP ALMY Department of Biomedical Sciences and Pathobiology V'irginia—Maryland Regional College of Veterinary Medicine Blacksburg, VA 24061 KEVIN L. ANDERSON Ruminant Medicine Department of Farm Animal Health and Resource Management College of Veterinary Medicine, North Carolina State University RaleiglL NC 27606 BEAU BAMBERG. ABOMASAL EMPTYING DEFECT (AED) IN SHEEP I BASICS DEFINITION Abomasal emptying defect (AED) is a syndrome of adult Suffolk sheep characterized by chronic, progressive weight loss and abomasal dilatation in the absence of mechanical obstruction. PATHOPHYSIOLOGY - The pathogenic mechanism for AED is unclear. The AED syndrome shares some characteristics of a human syndrome, chronic intestinal pseudo—obstruction that affects children and adults.
Alfected clinically appear to have a partial or complete gastric obstructiorL but none is present. Morphologic investigations of human patients indicate degenerative changes in the smooth muscle or the tunica muscularis andlor neurons of the enteric plexus. SYSTEMS AFFECTED Gastrointestinal GENETIC S Little information is available regarding genetic predisposition A pedigree analysis performed on a flock in which 11 of 92 Sufiolks were affected failed to show a hereditary pattern. INCIDENCE/ PREVALENCE Unknown GEOGRAPHIC DISTRIBUTION None SIGNALLIENT Species Sheep Breed Predilection.
AB OMASAL IMPA C T I ON Ln ’. BASICS OVERVIEW’ - Blockage of fluid and ingesta from the abomasum through the pylorus by feed sand gavel, or neurological deficit. 0 Pyloric obstruction from improper placement of percutaneous Euration of lefi-sided abomasum (“roll and toggle”) can result in abomasal impaction. 0 Signs can be acute or chronic and are characterized by loss of appetite, decreased or scant feces, distension of the abomas1mL weakness, dehydration metabolic alkalosis, and apparent abdominal pain.
Found in cattle and sometimes sheep. Usually isolated cases but also may have low morbidity associated with 1ow—quality forages. High mortality. 0 Abomasal emptying defect (AED) is a disease syndrome that affects Suflblk sheep and is characterized by distension and impaction of the abomasum. PATHOPHYSIOLOGY 0 Physical blockage of the outflow fiom the abomasum to the duodenum occurs. This may be due to the packing of straw or poor-quality roughages, sand, or gravel in the abomasum.
Damage to branches of the vagus nerve from reticuloperitonitis or lymphoma can decrease the emptying ability of the abomasum. Failure of fluid to move from the abomasum to the intestines results in dehydration and starvation. 0 Sequestration of hydrochloric acid in the abomasum can result in metabolic alkalosis. In sheep, no histologic lesion has been consistently associated with AED. There is no known etiology. In one study, histologic examination of celiacomesenteric ganglia from alfected sheep revealed scattered chromatolytic or necrotic neurons, without inflammation Chromatolytic neurons were observed more frequently in AED—afl'ected sheep than in healthy Sufiolk sheep. Neuronal necrosis was not observed in any of the healthy sheep.
Neuronal lesions of AED resemble dysautonomic diseases of humans and other animals. SYSTEMS AFFECTED Gastrointestinal GENETIC S N-’A. ABOMASAL UL CERS I BASICS DEFINITION - Damage to the abomasal mucosa contimring from erosion through complete perforation Often subclinical but may be clinical. Classified as type I (nonperforating ulcers), type II (nonperforating with severe blood loss), type III with localized peritonitis), and type IV with difluse peritonitis). Clinical signs associated with abdominal pairL blood loss, and peritonitis. Causes are not lcnowrL but may be associated with stress. Not associated with particular abomasal bacterial infections.
PATHOPHYSIOLOGY 0 Injuries to the protective mucosal layer allow acid and pepsin to dilfuse into the mucosa - Type I nonperforating ulcers have incomplete penetration, little local reaction, and minimal bleeding. Type II bleeding ulcers erode into a major blood vessel in the submucosa There may be distension of the abomasum and reflux of abomasal contents into the rurnen. There is usually melcna. Type III ulcers completely perforate the wall with leakage of fluid and local Adhesions form to viscera localizing the - Type IV ulcers perforate completely and the subsequent fluid leakage is not contained by adhesions, resulting in generalized SYSTEIWS AFFECTED Gastrointestinal GENETICS N/ A INCIDENCEIPREVALENCE Low, less than 1 or 2%. May be higher in some types of calf-raising systems. GEOGRAPHIC DISTRIBUTION N/ ‘A. ABORTION I BASICS DEFINITION Loss of the fetus from 60 days to term Prior to 60 days is considered embryonic mortality.
PATHOPHYSIOLOGY - Camelids rely primarily on t: he corpus luteum for producfion of progesterone and maintenance of pregnancy for die entire gestation - Maintenance of the corpus hrteum requires normal pregnancy recognition and establishment of placentation. Abortion is caused by any factor that acts directly or indirectly on the corpus lI. Iteum to cause luteolysis: - Treatment with prostagandin F2 alpha 0 Inflammatory or febrile affection - Endotoxemia 0 Stress such as heat stress, transport 0 Debilitating diseases - Abortion can be caused by factors that compromise fetal viability or placental integrity: - Placentitis 0 Placental insufliciency (endometrial fibrosis, uterine capacity in maiden females, 0 Direct insult to the fetus (mechanical or infectious) - Fetal malformationlabnormal pregnancy 0 Hormonal insufliciency or unbalance SYSTEMS AFFECTED Reproductivt%potenlially all systems may be aflected depending on the condition. /A.
ABORTION: BACTERIAL LE ’. BASICS OVERVIEW - Many species of bacteria may cause septicemia and/ or localized lesions in adult cattle with a subsequent abortion. These agents usually cause sporadic abortions. The route of infection is usually hematogenous rather than ascending as interruption of the cervical seal occurs less ofien in cows than ir1 mares.
Often, cows may be predisposed to abortion by these bacteria by some immunosuppressive condition such as bovine virus diarrhea (BVD). Two categories of bacterial abortiorr (1) ubiquitous environmental organisms: A. Pyogenes, E, coli, Bacillus spp.; Streptococcus spp.; (2) abortion secondary to specific disease: Pasteurella Salmonella spp., Haemaphilus samnus SYSTEMS AFFECTED Reproductive GENETIC S N-“A INCIDENCE/ PREVALENCE Cattle 0 In a 10-year survey; specimens fioru 8995 bovine abortions and stillbirths were evaluated for bacteria Bacteria were determined to be the cause of 1299 (14.49%) of the presenting abortion cases. The five bacteria most commonly associated with bovine abortion or stillbirth wereActinomyces pyogenes; 378 (4.22%); Bacillus 321 (3.58%); Listeria spp.; 121 (1.35°—‘6); Escherichia coli, 98 (1. O9°—‘6); and Leptospira interrogans, 79 (0.88%). Twelve other genera of bacteria were associated with or = 10 abortions or stfllbirths, and 12 more species were associated with 25,000 neutrophils';.LL): t: hyperfibrinogenemia (400 mg4'dI) is consistent with inflammatory disease.
The presence of immature neutrophils (e. G., lefi shift) is supportive of active Inflammatory disease results in cytolcine—mediated disturbances in iron metabolism and decreased availability for erythropoiesis. Lack of polychromasia and reticulocytes indicates nonregenerative anemia - Mild, nonregenerative anemia has been reported irn juvenile llamas alfected with juvenile llama imrmmodeficiency syndrome (JLIDS). Anemia is probably a result of chronic and repeated infections resulting in decreased iron availability. Imn Deficiency Anemia Iron deficiency may be primary or secondary. In either case, iron deficiency results in moderate nonregenerative anemia due to insuflicient iron for hemoglobin synthesis. Erythrocytes are (decreased MCV) due to an additional cell during development.
Hypochromasia (decreased MCHC) results from decreased hemoglobin concentration in the erythrocytes. Chronic blood loss can result in iron deficiency and nornregenerative anemia Trichostrongylus infection causes a mildly regenerative, normocytic, normochromic blood loss anemia Bleeding gastric ulcers can result in chronic blood loss. Copper Deficiency Anemia Copper deficiency causes nonregenerative anemia due to impaired absorption and utilization of iron. The majority of copper in the blood is bound to ceruloplasmin an enzyme that is remrired far the hirtdirw of irnn tn the transom‘? Nrntein transferfin Conner rleflrierwv mav be either nrirnarv rhle tn defiriertt intalre m secondary due to hiwh.
ANEMIA, RE GENERA T IVE: B 0 VINE LE ”. BASICS DEFINITION - Anemia in adult cattle is indicated by a PCV (or Hct) of less than 23%. 0 Bed cattle have higher hemoglobin, RBC, and PCV than breeds. 0 Anemias may be nonregenerative or regenerative. The presence of reticulocytes.
Polychromasia and increased red cell distribution width (RDW) is indicative of a regenerative response. Torrent on windows 8 rt tablets. Lactating dairy cattle tend to have lower values than nonlactating cows. 0 Bulls tend to have greater RBC counts than cows. Environmental seasonaL and physiological diflerences may afiect the hemogram 0 Diminished oxygen tension at elevated altitudes stimulates erythropoiesis resulting in increased RBC counts. PATHOPHYSIOLOGY - Anemia results from decreased production or increased destruction (hemolysis) or loss (hemorrhage) of erythrocytes. Regenerative anemias are caused by hemolysis or hemorrhage. 0 Anemia caused by hemolysis or hemorrhage and the related signs may be insidious or acute.
Recognition of the indicators of erythropoietic response (reticulocytosis, polychromasia, and increased RDVV’) to hemorrhage— or hemolysis—induced hypoxia will not be evident for 3 to 6 days after the onset of anemia because the proliferation and difierentiation of precursor cells of the erythropoietic series must occur. These events require several mitotic events and considerable protein, especially hemoglobin, synthesis. A single precursor cell may give rise to 16 to 32 mature RBCs Hemorrhagic Anemia Hemorrhage is caused by vessel injury or disease.
It may be internal (within the body) or external. With external hemorrhage.
Blood cells and their iron are lost from the system. Thus, the regenerative response is typically mild to moderate.
Chronic external blood loss (e. G., GI bleeding) ofien leads to a nonregenerative anemia due to iron depletion In peracute and acute hemorrhage, response to anemia-induced hypoxia will not be recognized by CBC parameters for 3 to 6 days alter the hemorrhage. Hemolytir: Anemia.
ANEMIA, RE GENERA T IVE: CAMELIDS I BASICS DEFINITION - A syndrome characterized by decreased circulating RBC mass (anemia in adult llamas and alpacas indicated by a PCV 525%; in camels a PCV 528% indicates anemia). Together with an appropriate compensatory increase in RBC production by the bone marrow.
The presence of polychromasia, reticulocytes: t nucleated eryfltrocytes are indicative of an appropriate regenerative response. Because it takes the bone marrow 3-5 days for a maximum response, evidence for regeneration may not be apparent until several days after the onset of anemia. High concentrations of erythrocytes are observed in healthy camelids, but because the cells have a small mean cell volume.
The PCV, or Hct. Is relatively low. PATHOPHYSIOLOGY - Anemia may result fiom either decreased production or increased destruction of erythrocytes. Regenerative anemias are most often associated with two general mechanisms: blood loss (hemorrhage) or hemolysis. Chronic blood loss can result in iron deficiency and nonregenerative anemia Trichostrongyle infection causes a mildly regenerative, normocytic, normochromic blood loss anemia - Hemolysis in camelids most commonly occurs secondary to anti-RBC antibodies formed against altered erythrocyte membrane antigens. Infectious organisms (e. Leptospira interrogans, T rypanosoma, hemotrophic A/ Iycoplasma), exposure of previously tmexposed or adsorption of complexes to the erythrocyte membrane can alter RBC membrane antigens and render RBCs susceptible to accelerated destruction or removal by the mononuclear-phagocylic system of the spleen and-’or liver (extravascular hemolysis).
Certain bacterial infections (ie., Clasmdium perflingem type A) cause direct erythrocyte damage due to hydrolysis of membrane phospholipids. The result is marked irmavascular hemolysis. RBC parasites such as Candidatu: Mycaplarma haemolamae (formerly Eperythrazoon spp. ) adhere to the surface of RBC membranes. Afiected erythrocytes are removed by the mononuclear—phagocytic system of the spleen andlor liver.
Young llamas and alpacas are more susceptible to acute infection and severe parasitemia with clinically sigtificant extravascular hernolysis. Anemia may be nonregenerative or regenerative depending on the presence or lack of other clinical problems.
Hemorrhagic Anemia RBCs are lost from the vasculature due to vascular injury or disease. Hemorrhage may be internal (within the body) or external. RBC lifespan is unaltered in this condition. Both blood cells and iron are lost from the body with external hemorrhagic anemia Thus, fire regenerative response is typically mild to moderate.
Blackwell's 5 Minute Veterinary Consult
Chronic external blood loss (e. GI bleeding) ofien leads to a nonregenerative anemia due to iron depletion. ANES T HESIA AND ANAL GESIA LE ’. BASICS OVERVIEW’ - Anesthesia; local regional (epidural. intrathecal), or general; local and regional methods most commonly employed in ruminants - Analgesia: local, regional, systemic, multimodal, short-term, long-term - Pain‘ an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage - Types: acute, chronic, visceral, and somatic 0 Sulfering: a reaction to the physical or emotional components of pair1 with a feeling of imcontrollability. Intolerability, and interminableness. Suflering implies a threat to the wholeness of patient comfort within the environment.
The 5 Minute Pediatric Consult
0 Virtually all anesthetics and analgesics are ojf—IabeI use in any ruminant species. Please see Suggested Reading below for guidelines on otf—label use of analgesic and anesthetic drugs ir1 ruminants. The relief of pain and sufiering ir1 ruminants can and should be accomplished within these guidelines. SYSTEMS AFFECTED CNS, musculoslceletal, respiratory GENETICS Nx'A INCIDENCEIPREVALENCE N.' A GEOGRAPHIC DISTRIBUTION Worldwide SIGNALMENT Species Potentially. All ruminant species Breed Predilections. ANES T R US LE ’.
BASICS OVERVIEVV Anestrus is the absence of behavioral signs of estrus activity or behavior, altlnough follicular waves are generally still present. PATHOPHYSIOLOGY Cattle are polyestrus. But cyclicity may be influenced by factors such as: - Nutrition 0 Environment 0 Physiological conditions - Breed - Managennernt Anestrus irn cattle can be a response to aberrant release patterns at the level of the hypothalamus (GnRI-I) or the pituitary (LH and FSH). SYSTEIVIS AFFECTED Endocrine-’metabolic, reproductive SIGNALMIENT Breed diflerences are related to 0 Lactational status 0 Nutritional intake 0 Estrus irnternsity and duration SIGNS History of female estrous cyclicity and hormonal patterns may increase estrus detection efliciencies. CAUSES AND RISK FACTORS Other causes may include 0 Anestrus females may actually be pregnant. AN GULAR LIMB DEF ORMI T Y La ’. BASICS DEFINITION - Angular linnb deformity (ALD) is a deviation from the normal axis of a limb (irn the frontal plane) and is defined by fine joint involved and tlne direction that the distal aspect of the limb is deviated - Valgus deformity: the linnb distal to the lesion deviates laterally.
Varus deformity the limb distal to the lesion deviates medially. ALDs are further described by the location of the pivot point (axis of deviation) and by the location of fine site of defective growth 0 Related conditions irnclude flexnrral deformities, tendon injuries, joirnt luxations, and rotational deformities. 0 Spider lamb syndrome (SLS) or hereditary chondrodysplasia (HC) is a hereditary condition irn young lambs characterized by a number of skeletal deformities. Including angular limb deformities. PATHOPHYSIOLOGY - ALDs are considered multifactorial irn origin and have congenitalperirnatal and developmental predisposirng factors.
Cattle and llamas have a complete osseous ulna In llamas, the distal ulnar epiphysis fuses with the distal radial epiphysis. This urnique development of the distal portion of the ulna is associated with forelimb valgus deformities irn crias. The ulnar epiphysis extends distally.
Crosses the radial physis, and finses with the radial epiphysis. This early fusion demands synchronous gowth to ensure normal limb development. 0 Most calves have a mild carpal valgus deformity of approximately 7 degees, which does not require treatment. Varus deformities irn cattle are abnormal and ofien need treatment. SYSTEl'IS AFFECTED MusculoskeletaL involving the tibia radius, ulna, carpusltarsus, arnd metacarpus/ metatarsus GENETIC S - The questions of heritability in angular limb deformities have not been defirnitively answered. 0 ALDs irn Jersey calves are genetically transmitted as a simple autosomal recessive trait.
ANTHRAX LE ’. BASICS DEFINITION Anfinrax is an almost irnvariably fatal septicennic disease caused by a large, gram—positive spore—forming bacterial rod Bacillus anthracir, which is part of fine normal soil flora in most geographic areas, particularly those with alkaline soils.
PATHOPHYSIOLOGY - Spores of the causal agent gain entry to the host by irngestioiL by inhalatiorL or through skin lesions. Once fine bacillus enters the body, it is irngested by macrophages and enters irnto lymphatic vessels and lymph nodes to cause lymphangitis and lymphadenitis. 0 The spores germinate to a vegetative form, multiply extracellularly, arnd are disseminated throughout the host.
The organisms produce toxins (lethal factor, edema factor, and protective antigen) that cause widespread damage of the vasculature and reticuloendofinelial system to result irn edema, tissue damage, shock, renal failure, anoxia and ultimately death INCIDENCEIPREVALENCE - In the United States, the disease is usually seen irn one or only a few arnimals at a time and is sporadic. Botln sporadic cases and outbreaks are otten associated with disruption of the soil. This disruption brings bacterial spores to fine soil surface where finey are ingested Similarly, animals gazing short gasses durirng drought periods may irngest spores. Outbreaks can occur over large areas if animals are fed contaminated feeds, such as meat and bone meal. Pastures can be contaminated by efluent from textile mills that were using animal products, such as wooL irn the manufacturing process. Morbidity varies widely but case mortality is 90%—95%.
0 Control efibrts are successful irn domestic species but wildlife can sufler large outbreaks. GEOGRAPHIC DISTRIBUTION The anthrax bacillus has a worldwide distribution but some areas have a higher rate of disease. SIGNALMIENT - Anthrax can aifect all livestock species but the major nnmirnant species—cattle, goats, and sheep—are more susceptible than horses and pigs. ARSENI C T 0.30 COSIS LE ’. BASICS OVERVIEW’ - Arsenic has been reported to be the second most common heavy metal irntoxication of catfie afier lead - Arsenic is still used irn herbicides, defoliants, and wood preservatives. 0 The use of arsenic—containirng products has decreased in the recent past as other insecticides and herbicides become available.
SYSTEIVIS AFFECTED 0 Gastrointestinal - Renal 0 Nervous (phenylarsonic compounds) Sources - Inorganic arsenic - Arsenate—natural, pentavalent form of arsenic - Trivalvent forms are manufactured inorganic arsenic: arsernic trioxide (insecticide and herbicide); trivalent arsernic (arsenite) - Pressure—treated woods (green in color): chromated copper arsenate (CCA). Catfie have been poisoned by consunnption of ashes from burnt pressure—treated wood - Inorgarnic arsenic is more commonly associated with irntoxication irn cattle. 0 Organic arsenic - 3-rnitro, 4-hydroxyphenylarsonic acid (3 nitro)—a feed additive 0 Thiacertarsamind¢%heartworm therapy 0 Monosodium methanearsonate (. /ISMA)—herbicide - Disodiunn methanearsonate (DSMA)—herbicide Toxic Dose 0 Toxicitv depends upon the formulation route of exposure. And duration of exposure.
AR T HROGR YPOSIS LE ’. BASICS DEFINITION - Congenital arthrogryposis is defined as a syndrome of persistent joint contracture (bilateral rigidity) present at birth and may involve one or multiple limbs (forelimbs and'or hind limbs). Arthrogryposis is often associated with cleft palate and primary CNS lesions such as hydranencephaly and syringomyelia - The arthrogryposis-hydranencephaly syndrome (AHS) is usually associated with flexural contracture of the limbs rather than angular limb deformities (ALDS). Crooked calf syndrome (CCD) is a congenital deformity condition widely recognized in western North America characterized by arthrogryposis, scoliosis, torticollis, and cleft palate.
CCD is observed in calves afier maternal ingestion of lupines containing the quinolizidine alkaloid anagyrine during gestation days 40-100. 0 Congenital arthrogryposis may be associated with denervation muscle atrophy. PATHOPHYSIOLOGY - Congenital arthrogryposis is considered multifactorial in origin and has multiple predisposing factors and etiologies. 0 It can be caused by a number of etiologc agents including plant teratogens (e.
G., lupines), spinal dysraphism, prenatal viral infections (e. G., Akabane virus), and in utero hormonal and vascular defects.
0 It may also be attributed to a decrease or lack of motion of the fetus during critical stages of development, such as malpositioning and overcrowding caused by the size of the fetus relative to the dam. 0 Ingestion of teratogenic plants (e. G., Astragalus or Oxytropis spp. = locoweed; Verratrum califarnicum = slcunlc cabbage; piperidine allcaloid—containing plants such as Lupinus, Conium, andNicoriana species). Repeated dosing or continuous low—level ingestion over time may result in cumulative intoxication and/ or teratogenesis. Teratogenic plant alkaloids may be transferred to the placenta and induce a sedative or anesthetic eflect in the fetus.
In CCD, there is often a lesion in the CNS 1:hat may result in reduced or complete absence of movement of the alfected body parts in the developing fetus, especially during the period of rapid growth. Studies have demonstrated a significant reduction in number of at-motorneurons in the cervical spinal cord May cause disruption in normal innervation of muscles leading to paresis and instability of the limb, or may result in hypotonic condition of extensor muscle and dysfimction of the radial nerve. Ntrnvivrn tn. I-I-llvIrI'.
ASPER GILL OSIS BASICS OVERVIEW - Aspergillus spp. Are ubiquitous environmental organisms that can cause disease in many mammalian species.
This saprophytic fungus is present in tire soil and other decaying matter. Aspergillus is an opportunistic pathogen and usually occurs secondary to chronic disease, immunosuppression, stress, or metabolic disturbances. It can also occur with chronic antibiotic or steroid use. 0 In ruminants, A. Fumigatus is the most common isolate involved in clinical disease.
The disease can manifest in ruminants as one of several forms including pulmonary, intestinaL systemic, andlor as a cause of abortion or SIGNALMIENT - In cattle, aspergrllosis is a major cause of mycotic abortion. Primary pulmonary infections are rare but can be caused by inhalation of spores from contaminated feedstufls. It can occur secondary to comment disease in a pulmonary or intestinal form.
Mastitis caused by Aspergillus has also occasionally been seen in cattle. Once infected, cattle may then develop a systemic aspergillosis due to invasion of blood vessels and dissemination of the organism throughout the body. Housed calves may be more susceptible to pulmonary infection. In sheep and goats, Aspergillus spp.
May cause a primary Disseminated aspergillosis may occur in conjunction with Primary pulmonary infections are rare in sheep and goats. Pulmonary and disseminated aspergrllosis have also been reported in llamas and alpacas, camels, American bison and cervidae. SIGNS Pubnanary - May cause few clinical signs. Mild respiratory disease andior weight loss may be the only symptoms. Other respiratory signs may include fever, anorexia, cough, nasal discharge, tachypnea dyspnea and recumbency. Development of pneumonia may be acute.
Jlastitis. ASPIRA T I ON PNE UM ONIA LE ’. BASICS DEFINITION Inhalation or accidental administration of large volumes of foreign liquids, aspiration of solids (foreign bodies, plant debris, d'n’t) resulting in gangrenous pneumonia, or, in the case of oils, lipid pneumonia PATHOPHYSIOLOGY Gangrenous pneumonia develops due to either infectious or chemical irritants damagng the airways and lung parenchyma SYSTEIVIS AFFECTED Primarily the respiratory system; secondarily, multiple organ system dysfunctionffailure GENETIC S N.' A INCIDENCE/ PREVALENCE Uncommon, usually accidental or due to inadvertent exposure to risk factors GEOGRAPHIC DISTRIBUTION Potentially worldwide, depending on species and environment SIGNALlIENT - Calves, lambs, and kids receive accidental orotracheal intubation when feeding colosmm or inhalation of meconium containing fetal fluids during diflicult parturition.
Blackwell’s Five-Minute Veterinary Consult: Avian presents complete information on diseases and conditions seen in birds in a quick-reference format ideal for clinical practice. Offers fast access to essential information on 128 avian diseases and syndromes. Written by leading experts in avian medicine. Uses the trusted Five-Minute Veterinary Consult format. Focuses on practical clinical knowledge. Includes access to a companion website offering algorithms, procedure guides, and client education handouts to download, edit, and use in practice.
Trusted by Physicians. 'Best medical website on the internet. Perfect balance between brevity and detail!' - Lori Fewin, MD, FAAP. 'The entire site is the best thing I have ever seen. Top notch great information.
Don't know how I ever lived without it!' - Melanie Denny-Schiltz, NP, CEN. '5MinuteConsult.com is a perfect extension of Dr. Domino's 5 Minute Clinical Consult book. This site gives me the added confidence in my clinical decision making process that no other resource has been able to provide.' - Mitchell Dunbar, MD.
How to create a virus using notepad harmful pdf downloads. The most trusted and well-known quick-reference resource available to veterinarians, Blackwell’s Five-Minute Veterinary Consult series includes this volume on ruminants. Hundreds of top specialists provide coverage of 420 topics arranged alphabetically from A-Z for efficient searching, with each topic indicating the species affected.
(PDF); 4426 p. Series: Blackwell's Five-Minute Veterinary Consult Note: This document is available in PDF and ePuB formats.
Haskell, ed., DVM, MPVM, PhD. University of California, Davis, CA (USA), Graduate Group in Comparative Pathology. Publisher: Wiley-Blackwell Publication date (print): 2009-03 ISBN (print): 978-0-7817-5325-8 ISBN (ebook): 978-0-470-96118-6.
Blackwell s Five-Minute Veterinary Consult Clinical Companion: Small Animal Endocrinology and Reproduction is a highly practical, clinically oriented guide to endocrine and reproductive disorders in small animals, ideally formatted for fast access in the veterinary practice. Provides a complete yet practical clinical manual on endocrine and reproductive problems in small animals Draws on the endocrinology and theriogenology sections of Blackwell s Five-Minute Veterinary Consult: Canine and Feline, supplying a greater depth of information in a similar quick-reference format Presents expanded information, additional topics, and color images throughout Arranged alphabetically for easy searching and reference Includes access to a companion website with client handouts in Word, which can be downloaded, edited, and used in practice.
Comments are closed.
|
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |