ANSCI 1100

• Animal Health


  A state of physical and physiological well-being of the animal
• Disease (negative ease)


  Any deviation from normal health in which there is marked physiological, anatomical or chemical changes in the animal's body
• Types of Disease


  • Infectious - caused by microorganisms
  • Non-infectious - caused by other factors aside from microorganisms (environment, hereditary)
• Causative Agents of Disease

  • Bacteria
  • Fungi
  • Virus
  • Rickettsia
  • Protozoa
  • Metazoan (Internal) Parasites
  • Arthropods (External Parasites)
• Bacteria


  • Could either be gram positive or gram negative
  • Can live within living or non-living organisms
• Morphology of Bacteria


  • Coccus - round shape
  • Bacillus - spiral shape
  • Spirochetes - round oblong shape
• Fungi


  • Eukaryotic
  • Non-photosynthetic, filamentous or unicellular organisms
  • Reproduces asexually or sexually
• Virus


  • Submicroscopic organisms that can be grown using living tissue
• Rickettsia


  • True bacteria but non-filterable and are gram-negative
  • Cultivated outside the host only in living tissues
  • Associated with the tissues of some arthropods
• Protozoa


  • Single-celled and eukaryotic
  • Intracellular parasites (lives inside the cell)
• Metazoan (Internal) Parasites


  • Flatworms/tapeworms - elongated and flat; considered as hermaphrodite: they can reproduce on their own
  • Flukes - also hermaphrodites (liver flukes in ruminants)
  • Roundworms - there are male and female but are not hermaphrodites
• Arthropods (External Parasites)


  • Mites
  • Ticks
  • Flies
  • Lice
  • Fleas
  • Mosquitos
• Classification of Disease According to Duration

  • Acute - Starts quickly and runs a short course
  • Chronic - Runs for a long period of time
  • Subacute - Clinical signs are shown to develop
  • Peracure - Destroys the animal before the clinical signs are signs
• Morbidity


  Number of animals affected by the diseases but not to die
• Mortality


  Number of animals dying from the disease
• Immunity


  • Natural
  • Artificial
• Active Immunity


  Antigen being given to the animal and the body produced antibodies<|>Recovering from a disease (natural) or infection of biological agent or vaccine (artificial) and has a longer duration
• Passive Immunity


  Animal's body given antibodies<|>Sucking of colostrum and placental transfer (natural) and injection of antiserum (artificial)<|>Duration is usually relatively short
• Prevention


  • Disinfection - process of converting a place or object from a potentially infective state into one which is free from infection
  • Quarantine - isolation or restriction on movement of animals to a certain designated area
• Anthrax


  Zoonotic disease - animal diseases can be passed onto humans<|>Caused by the spore forming bacterium Bacillus anthracis and most common in wild and domestic herbivores and in humans exposed to tissue from infected animals, contaminated animal products, or directly to spores<|>Incubation period is 3-7 days (ranges to 1-14)<|>There may be bloody discharges from the natural body openings<|>Absence of rigor mortis
• Anthrax in Humans


  • Cutaneous
  • GI anthrax following consumption of contaminated raw or undercooked meat
  • Inhalational anthrax or woolsorter's disease
• Prevention of Anthrax


  • Vaccination programs
  • Rapid detection and reporting
  • Quarantine
  • Treatment of asymptomatic animals
  • Burning or burial of suspected and confirmed cases
• Pullorum Disease


  Synonyms: bacillary white diarrhea, BWD<|>Etiology: salmonella pullorum<|>Clinical Signs: huddling, droopiness, diarrhea, weakness, pasted vent, gasping, and chalk-white feces, sometimes stained with green bile. Survivors become asymptomatic carriers with localized infection in the ovary<|>Transmission: spread primarily through the egg, from hen to chick, contaminated equipment, poultry by-product, feedstuffs, and carrier birds<|>Treatment: several sulfonamides, antibiotics are effective in reducing mortality<|>Prevention: breeder replacement flocks are tested before onset of production to assure pullorum-free status
• Tetanus


  Caused by a specific neurotoxin produced by Clostridium tetani in necrotic tissue<|>Can survive without oxygen<|>Birds are resistant while horses are most sensitive<|>The organism is found in soil and intestinal tract<|>Introduced into the tissues through wounds, particularly deep puncture wounds or wounds that are minor or healed<|>Localized stiffness, often involving the masseter muscles and muscles of the neck, the hindlimbs, and the region of the infected wound<|>Spasms of head muscles cause difficulty in prehension of food (lockjaw)
• Prevention and Treatment of Tetanus

  • Prevention: Vaccination with tetanus toxoid
  • Treatment: Antitoxin (tetanus AntiToxin), Drain and clean the wounds and administer penicillin or broad-spectrum antibiotics
• Brucellosis "Bang's Disease (in ruminants)"


  Contagious abortion, undulant fever in man<|>Caused by Brucella abortus (cattle), Brucella melitensis (goat and sheep), Brucella suis (swine), Brucella canis (dogs)<|>Organisms are shed in mild and uterine discharges, and the cow may become temporarily infertile<|>Natural transmission occurs by ingestion of organisms from aborted fetuses, fetal membranes, and uterine discharges<|>Brucellae may enter the body through mucous membranes, conjunctivae, wounds, or intact skin<|>Abortion is the most obvious manifestation and usually occurs on the last 3 months of pregnancy<|>Stillborn or weak calves, retained placenta, and reduced milk yield<|>Infected seminal vesicles, ampulla, testicles, and epididymis<|>Testicular abscesses may occur<|>Longstanding infections may result in arthritic joints in some cattle
• Control of Brucellosis


  • Testing and eliminating reactors using the screening test
  • Use replacement stocks from brucellosis-free areas or herds
  • Vaccination
• Infectious Coryza


  Causative Agent: haemophilus paragallinarum (gallinarum) - seen in chickens only<|>Clinical signs: swelling around the face, foul smelling, thick, sticky, discharge from the nostrils and eyes, labored breathing, and rales. The eyelids are irritated and may stick together<|>Transmission: direct bird-to-bird contant, inhalation of airborne respiratory droplets, and contaminated feed and/or water<|>Signs: copious, grayish, semifluid exudate on the infraorbital sinuses, caseous plugs may be found in the trachea of young birds, thickened air sacks<|>Treatment: water soluble antibiotics or antibacterials can be used like sulfa drugs,erythromycin, or tetracycline<|>Prevention: good management and sanitation along with vaccination (usually the layers are given coryza since they are taken care of longer
• Hemorrhagic Septicemia


  Caused by Pasteurella multocida and manifested by an acute and highly fatal septicemia in cattle and water buffaloes<|>Animals are infected by the direct or indirect contact<|>The source of the infective bacteria is thought to be the nasopharynx of bovine or buffalo carriers<|>Natural infection is acquired by ingestion or inhalation<|>The heaviest losses occur during the monsoon rains in southeast asia<|>Animals first show dullness, then reluctance to move, fever, salivation, and serous nasal discharge<|>Edematous swelling in the throat region and spreading to the parotid region, neck, and brisket<|>There is respiratory distress and usually the animal goes down and dies within hours
• Treatment and Prevention of Hemorrhagic Septicemia

  • Treatment: Sulfonamides, tetracyclines, penicillin, and chloramphenicol
  • Prevention: Vaccination using bacteria
• Hog Cholera or Swine Fever


  Viral diseases affecting only pigs and caused by pestivirus<|>Transmission: Direct contact between animals and indirect contact<|>Fever, cyanosis of the skin especially of extremities (ears, limbs, tail, snout)<|>Multifocal hyperaemia and haemorrhagic lesions of the skin, conjunctivitis<|>Dyspnoea, coughing<|>Ataxia, paresis, and convulsion<|>Mortality in young pics can approach 100%
• Prevention and Control of Hog Cholera


  • No treatment is possible
  • Affected pigs must be slaughtered and the carcasses buried or incinerated
  • Vaccination
• Transmissible Gastroenteritis


  Very important and highly infectious disease in the piglet caused by a coronavirus<|>The virus enters the pig by mouth and multiplies in the villi and destroys them<|>The virus multiplies in the intestine and is shed in large numbers in the feces<|>Signs: vomiting and acute watery diarrhea
• Treatment and Prevention of Transmissible Gastroenteritis

  • Treatment: No specific treatment
  • Prevention and Control: Follow strict treatment, Vaccination
• Foot and Mouth Disease (Aphthous Fever)

  It is a highly infectious viral disease of cattle, pigs, sheeps, goats, buffalo, and artiodactyl wildlife species<|>Characterized by fever and vesicles in the mouth and on the muzzle, teats, and feet<|>It is caused by an aphthovirus (Picornavirus)<|>Transmitted by contact between susceptible and infected animals<|>Can be transmitted respiratory or oral routes<|>All excretions and secretions from the infected animal contain virus<|>The incubation period for FMD is 2-14 days<|>Cattle salivate and stamp their feet as vesicles develop on the tongue, dental pad, gums, lips, and on the coronary band and interdigital cleft of the feet<|>Vesicles may also appear on the teats and udder<|>Lesions on the mammary gland and feet are frequently develop secondary infections
• Control of Foot and Mouth Disease

  • Vaccination and quarantine and restriction on the movement of animals
• Fowl Pox


  Synonyms: chicken pox, sore head, avian diphtheria, bird pox<|>Etiology: avipoxvirus (pox virus)<|>Transmission: Direct contact by mosquitoes<|>Clinical signs: 2 forms: Dry from (cutaneous form) and Wet form (diphtheric form)<|>Treatment: no treatment is available<|>Prevention: vaccination, control mosquitos
• Infectious Bursal Disease


  Synonyms: gumboro, IBD, infectious bursitis, infectious avian nephrosis<|>Causative agent: birnavirus (IBDV), Shed in feces, stable and difficult to eradicate, target the Bursa of Fabricius<|>Clinical signs: Chickens greater than 3 weeks of age — watery dropping, soiled vent and vent pecking, ruffled feathers. Chicks are listless and sit in a hunched position and become severely and permanently immunosuppressed (immune system will not respond and is weak)<|>Transmission: Bird to bird contact contaminated people and equipment<|>Lesions: Cloacal bursa is swollen, edematous, yellowish and occasionally hemorrhagic. Congestion and hemorrhage of the pectoral, thigh and leg muscles<|>Treatment: No specific treatment<|>Prevention: Vaccination
• Avian Influenza


  Synonyms: AI, flu, influenza, fowl plague<|>Etiology: type A influenza virus<|>Transmission: infected carcasses and manure, contaminated clothing and equipment, mechanical transmission<|>Clinical signs: Mild form — listlessness, respiratory distress, greenish diarrhea, transient drops in egg production, and low mortality. Highly pathogenic form — facial swelling, blue comb and white wattles, and respiratory distress dark red/white spots develop in the legs and combs of chicken, blood-tinged discharge from nostrils<|>Treatment: no effective treatment<|>Prevention: vaccination for milf form, but for lethal form, strict quarantine and rapid destruction of all infected flocks
• Newcastle Disease


  Synonyms: pneumoencephalitis<|>Etiology: paramyxovirus<|>Transmission: airborne, contaminated feed and equipment, through the egg<|>Clinical Signs: hoarse chirps in chicks, watery discharge from nostrils, labored breathing, facial swelling, paralysis, trembling, and twisting of the neck, mortality ranges from 10-80%, and laying birds decreased feed and water consumption and drop in egg production<|>Treatment: no specific treatment<|>Prevention: vaccination, good sanitation, and implementation of a comprehensive biosecurity program