VM midterm pt3.

Transmissible Cancer: A cancer that spreads between animals through direct transmission of cancerous cells.
Canine Transmissible Venereal Tumor (CTVT): A transmissible tumor in dogs spread mainly through coitus.
CTVT Origin: A single clone has colonized dogs worldwide, existing for over 11,000 years.
CTVT Immune Evasion: Tumor cells downregulate MHC molecules and create an immunosuppressive environment.
CTVT Treatment: Vincristine (chemotherapy) is effective; spontaneous regression can occur.
Devil Facial Tumor Disease (DFTD): A fatal transmissible cancer in Tasmanian devils spread through bite wounds.
DFTD Impact: Estimated 80% of wild Tasmanian devils have died from the disease.
DFTD Immune Evasion: DFTD cells do not express MHC molecules, preventing immune detection.
DFTD Evolution: Some Tasmanian devils show natural resistance due to genetic evolution.

Anthrax: A zoonotic disease caused by Bacillus anthracis, characterized by sudden death and hemorrhagic discharge.
Anthrax Transmission: Ingestion, inhalation, cutaneous exposure, or mechanical vectors.
Anthrax Pathogenesis: Spores survive in soil and activate inside a host, leading to vascular collapse and shock.
Tetanus: A non-contagious intoxication caused by Clostridium tetani, leading to rigid paralysis.
Tetanus Pathogenesis: Neurotoxin blocks neurotransmitter release, causing constant muscle contraction.
Tetanus Clinical Signs: Stiffness, lockjaw, recumbency ("sawhorse stance"), and respiratory failure.
Botulism: A neuroparalytic intoxication caused by Clostridium botulinum, leading to flaccid paralysis.
Botulism Pathogenesis: Toxin prevents nerve synapse function, leading to progressive paralysis and death.

Aerobe: Bacteria that require oxygen to survive.
Anaerobe: Bacteria that thrive without oxygen.
Facultative Anaerobe: Bacteria that can switch between aerobic and anaerobic respiration.
Obligate Intracellular Pathogens: Bacteria that can only survive inside host cells (e.g., Rickettsia, Chlamydia).
Virulence: A pathogen's disease-causing potential.
Exotoxin: A toxin secreted by bacteria that affects host cells.
Endotoxin: A toxin within bacterial cell walls, released upon bacterial death.
Bacterial Structure: Composed of capsule, cell wall, pili, flagella, and plasmids.

Abscess: A localized collection of pus within tissues.
Benign: Non-malignant and not spreading.
Comatose: Unconscious due to severe illness.
Edema: Excess fluid accumulation in body tissues.
Granuloma: A nodular inflammation where the immune system walls off foreign material.
Pathogenesis: The biological process leading to disease.
Morbidity Rate: The ratio of sick individuals to the population at risk.
Mortality Rate: The ratio of deaths to the total population at risk.
Necropsy vs. Autopsy: Necropsy is for animals; autopsy is for humans.
Zoonotic Disease: A disease that transmits between animals and humans.