Health
What is health as normality
This is used by the food and agriculture organization of the united nations
A healthy animal is defined as having a normal appearance and behaviour
What is positive health
The provision of a complete diet, and environment that is optimal for the animals physiological needs, comfortable to the animals sense, in which the animal is secure and free from fear with no undue challenge by parthenogenic micro-organisms or predators
What are viruses
Ultramicroscopic - pass through bacterial filters
Obligate intracellular parasites
Contain only one nucleic acid
May also predispose animals to bacterial infections
What are mycotic organisms - fungi and yeast
Plant like organisms responsible for mycotic infections or mycoses - ringworm, mycotoxins
What is neoplasia
Not very common in ruminants except for cancer eye and bovine leukosis
- malignant = characterized by rapid, uncrontrollable growth
-bengin
What is health as a biological function
Disease can be seen as a manifestation of malfunctioning physiology - structural or functional alteration in the cells
What factors are considered when classifying diseases
Species affected
Age
Body system
Cause
Timing and severity
What is bacteria
Another category of infectious disease of major importance to livestock
Microscopic, walled, unicellular organisms which multiply asexually
Large heterogenous group
What are parasitic dieases
Often a more serious problem in warmer wetter climates but there are some of economic concern in western Canada
Development of resistance to parasiticides over the last 15 years has become an important consideration
Generalized adverse reaction to prior sensitization by an allergen
What is health as homeostasis
The concept of homeostasis is related to the maintenance of a delicate balance within the organism or within the processes in the organism
this concept is firmly established in the discipline of psychology and is almost considered a law of nature
What is the difference between acute, chronic and peracute severity
Acute - severe signs and a short course of 12-24 hours
Chronic - persisting for a long time, usually more than a week
Peracute - very acute, a duration of a few hours only
What is chlamydiae?
Another group of obligate intracellular organism
Formerly thought to be large viruses, now are classified with bacteria
Recognized as a distinct group mostly because of their unique and complex method of reproduction
Possess both DNA and RNA
Affected by some antibiotics
Associated with airborne infections of the respiratory system
What are the classifications of parasitic diseases
Ectoparasites - live on the host
Endoparasites - live within the host
Family - Arthropods, and helminths
Chemical - toxicological diseases, non-plant poisoning such as lead toxicity, plant poisonings \
Physical - often traumatic accidents, can be physical characteristic of feed, smoke exposure, uterine prolapse
What is health as a physical and psychological well being
Related to animal welfare
WHO defines health as a state of complete physical, mental and spiritual well being
productivity in farm animals might be considered as a complement of health in farm animals
What are the type of infectious disease agents
Prions
Viruses
Bacteria
Fungal organisms
Protozoan parasites
Helminth worms
Arthropod parasites
What is Rickettsia
Appear to be closely associated with gram negative bacteria
Smaller than most bacteria
Obligate intracellular parasites
Multiply by binary fission
Susceptible to some antibiotics
usually spread by arthropod vectors
What are inherited defects
Passed down genetically from one generation to another
Over 100 genetic diseases have been identified
What are nutritional diseases
Caused by deficiencies or excess of various nutrients
More common in high production settings
Can often affect a large proportion of population
diet may be deficient in a nutrient
Nutrient may not be biologically available or bound by another substance
The animal has an increased requirement
Reduced absorption through GI tract
What is health as productivity including reproduction
This is probably the only definition that cannot be applied to humans or companion animals
This concept of health is much less common in literature, however some definitions would state that a healthy animal grows, reproduces, and behaves in a manner which has come to be regarded as normal for its species and type
What are prions
Novel infectious entities that differ from viruses
An "infectious" proteins
PrP which exists in normal nervous tissue
The infectious form of the protein changes shape and causes pathology in the brain
What is mycoplasmopsis
The smallest organism known that is capable of growth and repro outside of living cells
Have some properties in common with gram positive bacteria
Contain both DNA and RNA
Lack a cell wall but have limiting membrane
Extremely variable in shape
difficult to grow
What are the types of non-infectious diseases
Inherited defects
Metabolic diseases
Nutritional diseases
Physical and chemical agents
Allergies
Neoplasia
What are metabolic diseases
Abnormalities of metabolism that are neither induced by or related to other diseases
Two components - anabolism or catabolism
Usually associated with high production