Swine_5_Conditions_diseases_in_gilts_sows_boars_Spring_2025

Conditions and Diseases in Swine

Overview

• Presented by Munetsi Tagwireyi and Ailbhe King, Assistant Professors in Large Animal and Production Animal Medicine.

Learning Objectives (Page 2)

• Understand the impact of infectious diseases on reproductive performance and productivity in swine.

• Review the presentation, clinical signs, diagnosis, and treatment of specific diseases:

  • PRRSV (Porcine Reproductive and Respiratory Syndrome Virus)

  • Leptospirosis

  • Parvovirus

  • Brucellosis

  • Rectal prolapse and stricture

  • Vaginal prolapse

  • Porcine Stress Syndrome (PSS)/Malignant Hyperthermia

  • Mycoplasma hyosynoviae

Common Conditions (Page 3)

• A variety of ailments observed in swine that impact health include:

  • Skin issues (abrasions, abscesses, and mange)

  • Gastrointestinal problems (constipation, diarrhea, gastric ulcers)

  • Respiratory diseases (pneumonia, mycoplasma infections)

  • Reproductive issues (mastitis, agalactia)

  • Neurological conditions (meningitis, ataxia)

  • Infectious diseases (swine fever, leptospirosis, enteroviruses)

Porcine Reproductive and Respiratory Syndrome (PRRS) (Pages 4-8)

Introduction

• Infectious virus characterized as an enveloped RNA arterivirus, specifically affecting pigs.

Pathogenesis

• Has a high affinity for pig macrophages leading to significant immune suppression.

Clinical Signs in Naïve Herds (Page 5)

• Late-term abortions, stillbirths, mummies, and weak piglets.

• Respiratory disease evident across all ages, particularly in sows and gilts with signs of fever and coughing.

Clinical Signs in Endemic Herds (Page 6)

• Similar reproductive issues with increased mortality rates in piglets.

Control Measures (Page 7)

• Exposure of gilts to older sows prior to breeding.

• Use of PRRS-free semen and vaccination strategies, with modified-live vaccines reducing fetal losses but not for pregnant sows.

Leptospirosis (Pages 8-12)

Causative Agents

• Multiple serovars of Leptospira species, showing preference for kidneys and genital tract.

Pathogenesis

• Enters through mucous membranes, leads to systemic leptospiremia impacting vital organs and causing capillary damage.

Clinical Signs (Page 10)

• Often mild in mature swine; severe in young piglets (hemolytic anemia, jaundice).

Diagnosis and Control (Pages 11-12)

• Diagnosis through serology and microscopic methods. Prevention via environment management, vaccination, and antibiotic treatment.

Parvovirus (Pages 13-16)

Disease Impact

• Causes reproductive failures in naïve dams, leading to mummified fetuses and decreased litter sizes.

Epidemiology (Page 14)

• Highly prevalent with possible transmission via secretions and transplacental infection.

Pathogenesis and Diagnosis (Pages 15-16)

• Affects fetuses between 35-70 days of gestation; diagnosis via identification of PPV antigen.

Control Measures

• Primarily vaccination strategies to prevent infection.

Brucellosis (Pages 17)

Causative Agent

• Brucella suis, primarily prevented through herd management.

Clinical Signs

• Abortion during any stage of gestation, often without visible illness in sows.

Prevention

• Typically involves depopulation of infected herds and limiting contact with feral swine.

Rectal Prolapse (Pages 18-20)

Causes

• Due to conditions like tenesmus, dysuria, and chronic coughing.

Treatment Protocol

• Involves cleaning, replacing, and using a purse-string suture pattern for fixation.

Stress-Related and Prolapse Conditions (Pages 24-27)

Porcine Stress Syndrome (PSS)

• Genetic predisposition related to calcium channel mutation causing uncontrolled calcium release leading to severe stress reactions.

Clinical Manifestations

• Includes muscle necrosis, pale soft exudative pork, and acute death due to stress or transportation.

Prevention Strategies

• Proper housing, handling, and monitoring practices to reduce stress.

Knowledge Checks (Pages 31, 56)

• Regular assessments of conditions in swine for signs of several infectious diseases, focusing on respective symptoms, and recommending appropriate treatment steps.