Lecture 8: Study Guide

Uterine Prolapse

• Most Common In: Dairy & beef cows, ewes; less frequent in sows

• Pathophysiology: Tip of uterine horn invaginates

• Predisposing Factors:

  • Excessive traction (dystocia, retained fetal membranes)

  • Uterine atony, hypocalcemia, lack of exercise

  • Grazing estrogenic pastures

  • Occurs immediately postpartum (cervix open, uterus lacks tone)

• Treatment:

  • Remove placenta, clean endometrial surface

  • Reduce edema: apply sugar, rinse with hypertonic saline

  • Administer epidural anesthetic

  • Replace uterus carefully (recumbent or standing positions)

  • Apply steady pressure from cervix toward uterine horns (avoid fingertips)

• Complications:

  • Laceration, necrosis, infection

  • Delayed treatment → shock, hemorrhage, uterine artery rupture

  • Prolapsed bladder/intestines must be repositioned

Vaginal Prolapse

• Most Common In: Cattle & sheep

• Occurs: Last trimester of pregnancy

• Predisposing Factors:

  • Increased intra-abdominal pressure (gravid uterus, fat, rumen distension)

  • Recumbency, lack of exercise, estrogenic exposure (plants, drugs)

  • Breed predisposition (Brahman, Hereford, Kerry Hill, Romney Marsh)

• Grades:

  • Grade I: Intermittent prolapse (visible when recumbent)

  • Grade II: Continuous prolapse

  • Grade III: Prolapse with bladder/cervix involvement

  • Grade IV: Chronic prolapse with necrosis/infection

• Treatment:

  • Epidural anesthetic, lavage, lubricate, reposition

  • Buhner suture to secure (leave space for urination)

  • Retention devices may cause discomfort

Abortion

• Definition: Termination of pregnancy after organogenesis, before fetal viability

• Types:

  • Early Embryonic Death: Pre-organogenesis loss

  • Stillbirth: Full-term, non-viable fetus

• Causes:

  • Non-Infectious: Genetic, twinning, heat stress, toxins (Ponderosa pine, moldy sweet clover), vitamin deficiencies, MLV vaccines

  • Infectious: BVD-V, Brucellosis, Campylobacter, Leptospirosis, Neosporosis, Q-Fever, Toxoplasmosis, Trichomoniasis

• Diagnostics:

  • Fetus & placenta (fresh condition, histopathology, PCR, cultures)

  • Maternal serum (paired samples to detect seroconversion)

Specific Infectious Causes of Abortion

• Brucellosis: Brucella abortus, zoonotic, 80% abortion rate, 7-month gestation

  • Prevention: Calfhood RB-51 vaccine, avoid raw milk

• Vibrio (Campylobacteriosis): Campylobacter fetus venerealis, venereal, causes infertility & late-term abortion

  • Prevention: AI, vaccination

• Leptospirosis: Various serovars, lifelong renal/repro infections, zoonotic

  • Prevention: Vaccination, elimination of infection sources

• Neosporosis: Neospora caninum, protozoan, common in cattle, transmitted by canines

  • No Treatment, control via biosecurity

• Q-Fever: Coxiella burnetii, zoonotic, causes stillbirths/abortion

  • Prevention: Hygiene, PPE, vaccination

• Toxoplasmosis: Toxoplasma gondii, cat-ovine cycle, late-term abortion in sheep/goats

• Trichomoniasis: Tritrichomonas foetus, protozoan, venereal, infertility, abortion, bulls asymptomatic

  • Prevention: Biosecurity, vaccination, remove infected bulls

Mycotoxins & Reproductive Issues

• Zearalenone: Estrogenic mycotoxin from Fusarium spp.

  • Effects: Infertility, embryonic death, reduced litter size

  • Sources: Contaminated corn, wheat, barley, silage

• Prevention: Feed management, toxin testing

Prolonged Gestation

• Causes: Defective hypothalamic-pituitary-adrenal (HPA) axis, genetics, toxins, infections

• Diagnosis: Fetal necropsy, gestation length deviation

• Treatment: Induction (corticosteroids, prostaglandins), C-section if necessary

Retained Fetal Membranes (RFM)

• Failure to expel placenta:

  • Horses: Within 3 hours

  • Cattle: Within 24 hours

• Complications: Metritis, systemic illness (mastitis, pneumonia, ketosis)

• Treatment:

  • No manual removal

  • Trim excess tissue, monitor for systemic disease

  • Prevention: Proper dry cow diet management

Metritis, Endometritis & Pyometra

• Metritis: Postpartum bacterial infection

  • Treatment: Antibiotics, supportive care

• Endometritis: Chronic uterine inflammation, infertility

  • Causes: Poor conformation, repeated breedings, infections

  • Diagnosis: Culture, ultrasound

• Pyometra: Accumulation of pus in the uterus

  • Treatment: Uterine lavage, antibiotics, prostaglandins

Contagious Equine Metritis (CEM)

• Highly Contagious: Causes infertility, mucopurulent discharge

• Diagnosis: Bacterial culture

• Treatment: Ineffective, requires rigorous hygiene and control measures

Key Takeaways:

• Prevention is crucial (hygiene, biosecurity, vaccination)

• Timely diagnosis & treatment reduce complications

Many reproductive diseases are zoonotic, posing human health risks