Livestock Diseases by Etiology
Bacterial Diseases
- Anthrax (Bacillus anthracis)
- Blackleg (Clostridium chauvoei)
- Botulism (Clostridium botulinum)
- Tetanus (Clostridium tetani)
- Tuberculosis (Mycobacterium bovis)
- Brucellosis (Brucella spp.)
- Salmonellosis (Salmonella spp.)
- Colibacillosis (Escherichia coli)
- Leptospirosis (Leptospira spp.)
- Strangles (horses, Streptococcus equi )
- Johne’s disease (Mycobacterium avium subsp. paratuberculosis)
- Actinomycosis ("lumpy jaw" in cattle, Actinomyces bovis )
Viral Diseases
- Foot-and-Mouth Disease (FMD, Picornavirus)
- Rabies (Rhabdovirus)
- Newcastle Disease (poultry, Paramyxovirus )
- Canine Distemper (Morbillivirus )
- African Swine Fever (Asfarvirus )
- Peste des Petits Ruminants (PPR, Morbillivirus )
- Infectious Bovine Rhinotracheitis (IBR, Bovine Herpesvirus-1 )
- Equine Influenza (Orthomyxovirus )
- Feline Panleukopenia (Parvovirus)
- Avian Influenza (Orthomyxovirus)
- Swine Influenza (Orthomyxovirus)
Chlamydial Diseases
- Enzootic Abortion of Ewes (Chlamydia abortus)
- Psittacosis/Ornithosis (birds, Chlamydia psittaci )
- Feline Pneumonitis (Chlamydia felis)
Prion Diseases
- Bovine Spongiform Encephalopathy (BSE) – “mad cow disease” in cattle
- Scrapie – sheep and goats
- Chronic Wasting Disease (CWD) – deer, elk
- Transmissible Mink Encephalopathy – farmed mink
- Kuru / Creutzfeldt-Jakob Disease (CJD) – humans (zoonotic relevance)
Fungal Diseases (Mycoses)
- Ringworm (Dermatophytes: Microsporum, Trichophyton)
- Aspergillosis (Aspergillus fumigatus)
- Histoplasmosis (Histoplasma capsulatum)
- Blastomycosis (Blastomyces dermatitidis)
- Candidiasis (Candida albicans)
- Cryptococcosis (Cryptococcus neoformans)
Protozoan Diseases
- Coccidiosis (Eimeria spp. , poultry, cattle, small ruminants, rabbits)
- Babesiosis ("redwater," Babesia spp. )
- Trypanosomiasis (Trypanosoma spp.)
- Theileriosis (Theileria parva, T. annulata)
- Trichomoniasis (Tritrichomonas foetus)
- Toxoplasmosis (Toxoplasma gondii)
- Leishmaniasis (Leishmania spp.)
Diseases Associated with Helminth Parasites
- Fasciolosis (liver fluke, Fasciola hepatica )
- Haemonchosis (barber’s pole worm, Haemonchus contortus )
- Ostertagiasis (Ostertagia ostertagi)
- Ascariasis (Ascaris suum , pigs)
- Strongylosis (horses, Strongylus spp.)
- Trichuriasis (whipworm, Trichuris spp. )
- Hydatidosis (Echinococcus granulosus)
- Cysticercosis (Cysticercus bovis, C. cellulosae)
Diseases Associated with Arthropod Parasites
- Mange (mites: Sarcoptes, Demodex, Psoroptes )
- Tick infestation (Rhipicephalus, Ixodes, Boophilus)
- Flea allergy dermatitis (Ctenocephalides felis)
- Lice infestations (Haematopinus, Linognathus, Damalinia)
- Warble fly infestation (Hypoderma bovis)
- Screwworm (Cochliomyia hominivorax)
Metabolic Diseases
- Ketosis (dairy cows, negative energy balance)
- Milk Fever (hypocalcemia, parturient paresis)
- Pregnancy Toxemia (ewes, does)
- Hypomagnesemic Tetany (grass tetany)
- Acidosis (ruminal acidosis)
- Urolithiasis (urinary stones in ruminants)
- Laminitis (linked to carbohydrate overload in horses/cattle)
Nutritional Deficiency Diseases
- Rickets (calcium, phosphorus, or vitamin D deficiency)
- Osteomalacia (adults, similar to rickets)
- White Muscle Disease (selenium/vitamin E deficiency)
- Grass Tetany (magnesium deficiency)
- Anemia (iron deficiency, especially piglets)
- Pica (phosphorus deficiency)
- Goiter (iodine deficiency)
- Night blindness (vitamin A deficiency)
Diseases Caused by Physical Agents
Trauma & Mechanical Injuries
Including Fractures, Wounds, Dislocations, Hematomas and Contusions.
Heat-Related Disorders
Including heat stroke, heat exhaustion, burns and photosensitization.
Cold-Related Disorders
Including frostbite, hupothermia, chilblains
Radiation-Related Conditions
Sunburn (Solar dermatitis), Skin cancer, radiation burns
Pressure & Confinement Injuries
Including Decubital Ulcers (Pressure Sores), Sole Ulcers / Laminitis, Myopathy (“Downer Cow Syndrome”).
Electrical & Lightning Injuries
Electrocution and Lightning Strike Injuries
Drowning & Suffocation
Drowning, Smothering and Aspiration Pneumonia
Other Physical Agents
- Foreign Body Injuries – traumatic reticuloperitonitis (“hardware disease” in cattle)
- Choking – feed obstruction in cattle, dogs, horses
- Noise-Induced Stress/Deafness – dogs (fireworks, gunfire)
- Physical Restraint Injuries – rope burns, neck abrasions, horn damage
Diseases Associated with Inorganic and Farm Chemicals
Heavy Metal Poisoning (Inorganic Compounds)
- Lead Poisoning
- Arsenic Poisoning
- Mercury Poisoning
- Copper Toxicity
- Selenium Toxicity (“Alkali Disease” or “Blind Staggers”)
- Fluorosis
Fertilizers and Soil Chemicals
- Nitrate/Nitrite Poisoning
- Ammonia/Anhydrous Ammonia Toxicity
Pesticides and Herbicides
- Organophosphate Poisoning
- Carbamate Toxicity
- Chlorinated Hydrocarbon Poisoning (e.g., DDT, Lindane)
- Paraquat/Herbicide Poisoning
Rodenticides
- Anticoagulant Rodenticides (Warfarin, Brodifacoum)
- Cholecalciferol (Vitamin D analog rodenticides)
- Zinc Phosphide Poisoning
Disinfectants & Farm Chemicals
- Phenol Poisoning
- Cresol/Creosote Toxicity
- Formalin/Chlorinated Disinfectants
Other Notable Chemical Toxicities
- Salt (Sodium Chloride) Poisoning / Water Deprivation
- Urea Poisoning (Non-Protein Nitrogen Toxicity)
Toxin-Related Diseases
- Botulism (neurotoxin from Clostridium botulinum)
- Mycotoxicosis (aflatoxins, ochratoxins, ergot alkaloids)
- Enterotoxemia (Clostridium perfringens toxins)
- Snake envenomation
- Plant poisonings (e.g., Lantana camara, Crotalaria, oleander, cyanogenic plants)
- Lead, arsenic, and other heavy metal poisoning
Diseases Caused by Allergic Reactions
- Equine Recurrent Airway Obstruction (RAO/Heaves) – dust, moldy hay allergens
- Atopic Dermatitis – dogs and cats (skin allergy due to pollen, dust mites, food allergens)
- Flea Allergy Dermatitis (FAD) – hypersensitivity to flea saliva (dogs, cats)
- Sweet Itch (Insect Bite Hypersensitivity) – horses (reaction to Culicoides bites)
- Milk Allergy in Calves – hypersensitivity to milk proteins
Genetic Diseases in Animals
- Albinism – absence of pigmentation (all domestic species)
- Chondrodysplasia (dwarfism forms) – dogs, cattle, sheep
- Hydrocephalus – multiple species
- Cryptorchidism (retained testes) – horses, dogs, cats, pigs
- Polydactyly (extra digits) – cats, chickens, cattle
Cattle
- Bovine Leukocyte Adhesion Deficiency (BLAD) – Holstein cattle
- Complex Vertebral Malformation (CVM) – Holstein cattle
- Bovine Progressive Degenerative Myeloencephalopathy ("Weaver syndrome") – Brown Swiss cattle
- Deficiency of Uridine Monophosphate Synthase (DUMPS) – Holsteins
- Factor XI Deficiency – Holsteins, Japanese Black cattle
- Arachnomelia (spider calf syndrome) – Brown Swiss, Holstein
Horses
- Hyperkalemic Periodic Paralysis (HYPP) – Quarter Horses, American Paint Horses
- Polysaccharide Storage Myopathy (PSSM) – Quarter Horses, Warmbloods, draft breeds
- Severe Combined Immunodeficiency (SCID) – Arabian horses
- Hereditary Equine Regional Dermal Asthenia (HERDA) – Quarter Horses
- Cerebellar Abiotrophy (CA) – Arabians
- Lethal White Foal Syndrome (Overo lethal white, OLWS) – American Paint Horses
Dogs
- Hip Dysplasia – large breeds (German Shepherds, Labradors, Rottweilers)
- Progressive Retinal Atrophy (PRA) – many breeds (Collies, Irish Setters)
- Collie Eye Anomaly (CEA) – Collies, Shetland Sheepdogs
- Degenerative Myelopathy – German Shepherds, Corgis
- Von Willebrand’s Disease – Dobermans, Shetland Sheepdogs
- Muscular Dystrophy – Golden Retrievers
- Cystinuria – Newfoundlands, Bulldogs
Cats
- Polycystic Kidney Disease (PKD) – Persian cats and related breeds
- Hypertrophic Cardiomyopathy (HCM) – Maine Coon, Ragdoll
- Progressive Retinal Atrophy (PRA) – Abyssinians, Siamese
- Hemophilia B – British Shorthair
- Spinal Muscular Atrophy (SMA) – Maine Coon cats
Sheep & Goats
- Spider Lamb Syndrome (Hereditary Chondrodysplasia) – Suffolk and Hampshire sheep
- Hereditary Splayleg – sheep and goats
- Goat Myotonia Congenita ("Fainting goats") – Tennessee fainting goats
- Entropion (inward eyelids) – hereditary in some sheep breeds
Pigs
- Porcine Stress Syndrome (PSS) – associated with malignant hyperthermia in Landrace, Pietrain
- Rectal/Anal Atresia – hereditary defect
- Congenital Tremors (type AII) – some pig lines
- Scrotal/Ventral Hernias – hereditary predisposition
Poultry
- Tibial Dyschondroplasia – broiler chickens, turkeys
- Crooked Toes – hereditary trait in some chicken lines
- Hypopigmentation ("Albinism") – rare genetic defect in poultry
Diseases of Complex or Unknown Etiology
- Colic in Horses – dietary, management, stress, parasites
- Feline Idiopathic Cystitis (FIC) – stress, diet, genetics, environment
- Lameness in Dairy Cattle – housing, nutrition, infection, conformation
- Bovine Respiratory Disease Complex (BRDC) – viruses, bacteria, stress, environment
- Mastitis (certain chronic or recurrent forms) – pathogens, milking hygiene, cow immunity, environment
- Sudden Infant Piglet Death Syndrome (SIDS-like) – uncertain, multiple factors suspected
- Johne’s Disease (clinical progression) – Mycobacterium avium subsp. paratuberculosis infection influenced by genetics, nutrition, environment
Take Home
Animal diseases can arise from a wide variety of causes, broadly classified into infectious agents such as bacteria, viruses, fungi, protozoa, helminths, arthropods, and prions, as well as non-infectious factors including nutritional deficiencies, metabolic imbalances, toxins, physical agents, and exposure to inorganic or farm chemicals. Infectious diseases often spread rapidly within populations, while parasitic infestations may cause chronic production losses. Nutritional and metabolic disorders usually reflect imbalances in diet or physiology, and toxic diseases result from exposure to poisonous plants, microbial toxins, chemicals, or heavy metals. Physical agents such as trauma, heat, cold, and radiation can also cause significant injury and disease. In addition, some conditions are genetic, allergic, or multifactorial in origin, influenced by complex interactions between the animal, environment, and management. Together, these categories highlight the diverse etiologies of animal diseases and the importance of a comprehensive veterinary approach to diagnosis, prevention, and control.