Are antibodies given for active immunity?
What does PAMP stand for?
Pathogen associated molecular patterns
What is an immune response?
antibodies in colostrum or given infejtion may be highly effective but dont persist more than a few weeks or months
Describe the concept of self versus non self and where failures result in
- recognition and elimination of foreign proteins (antigens) without damaging normal cells and tissues
- Failures result in:
- -tolerance (failure to fight infection) foreign substance was able to invade
- -autoimmune disease (body mounts a reaction against own cells)
- -allergic reaction (exaggertated reaction to non-pathogens), have issues recognising threats and react against non threatening things
How can an animals immune system be compromised?
- Stress- (can be stimulated by drugs ie cortisol injection = "pharmacologicaly stressed it")
- Body Condition (too skinny or fat)
- Parasitism- gives poor body condition
- Nutrition- cant mount good immune response if doesnt have proper nutrition, or if cow gave birth if not good nutrition she cant give good immuniity to calf through milk
What are the trace minerals affecting immunity?
Requirements to get an adequate immune response
- A healthy animal
- effective vaccine given properly
How do trace minearl dificienceies effect immunity?
- decreased disease resistance
- if sick then they are slower to recover or they may relapse more
- poorer response to vaccination
- (certain minerals are necessary to produce proper antibodies- give through feed and salt blocks)
What stresses may be cumulative (and effect welfare)?
weaning, shipping, mixing, diet, weather
What is the difference between vaccinations and immunizations?
- vaccination: the process of giving an injection for the prevention or treatment of infectious diseases
- immunizations: to make the animals immune to something
- difference? vaccination does not guarantee immunity
What is the challenge in analyzing animals immunity in herds?
Looking at different animals its hard to tell which are in health and which have disease because they all develop different immunity
What are some reasons for vaccine failures?
- 1. incubating siease at the time of vaccination (already sick)
- 2. Something happened to the vaccine to make it ineffective
- (ie vaccine not kept in fridge)
- 3. physiologic status of the vaccinated animal may make it less responsive or unresponsive to the vaccine
- 4. The host may be exposed to an overwhelming amount of the infectious agent (too much infection)
What are the vaccine factors?
- antigenic components (modified or partial form of virus)
- homologous antigens (antigen reacting with the antibody it induced)
- heterologous antigens (antigens that look the same) an antigen that reacts with an antibody that is not the one that induced its formation.
- cross protection (protection of a closely related strain)
- adjuvents- a substance that enhances the body's immune response to an antigen
What are some administration factors in vaccinations?
- environmental/ storage stess
- improper injection equipment
- sterilization practices (ie disinfect but dont rinse out)
- mixing products in syringes (may be incompatible)
- route of injection
- aseptic technique
- *Animals have different responses to vaccines
What is the percentage of the herd that needs to be vaccinated so that not everybody is at risk?
- 75-80% of the herd must be vaccinated or everyone is at risk
- if not then even those that are vaccinated need a high dose to fight of infection
What are animal factors in vaccine failures?
- Maternal blockade
- immune suppression
- concurrent diseases
- drugs ie corticosteroids
- nutritional status
- incubation of disease
Define infectious disease
- disease that is caused by a living agent (bacteria, viruses, protozoa, fungi)
- although an infectious disease may or may not be contagious- most are transmissinle (ie tetanus, bladder infection)
- time consuming: 5 yrs and therefore expensive to keep animal, and welfare issue
denotes the disturbances caused by entrance growth and activity of the disease causing agent in the body
How do you prove that a vaccine works?
- vaccine research is complicated
- because the best way to prove it works is to isolate the animals and then expose them to see if they get it
What are the steps to getting an infection (microbrial host interactions)?
- physical encounter between the host and microorganism
- microorganism colonization of host surface (such as internal gut lining, or external skin)
- microorganisms enter, invade, and spread
- outcome: infection vs the hosts defense
What does disease transmission imply? (3 steps)
- presence of a pathogenic organism
- the intervening agents (vector or fomite ie towel or boots)
- a portal of entry into the susceptible animal
For disease transmission what are some types of pathogenic organisms
bacteria, viruses, protozoa, fungi, multicellular parasites
are all microorganisms problematic?
no most are harmless, some are opportunists, while others are quite beneficial or necessary to health maintenance
For disease transmission what are some types of intervening agents?
- -inanimate vectors or fomites: feed & water, transport vehicles, bedding, stalls, troughs, needles and syringes
- -animate vectors: arthropods -flies lice and ticks, mammals- rodents, wild animals, other farm animals, humans
For disease transmission what are some types of portal of entry?
- routes or pathways into the body depends on the enfectious agent and the vector involved
- the most common portals of entry into the body include: into cuts, punctures or abrasions of the skin; through mucus lining, GIT, uro-genital trace
What is disease resistance (normal)
- an animal (host) will inevitably be exposed to pathogenic organisms (agent)
- an animal capable of warding off a particular pathogen are considered "resistant"
- animals in good health normally have primary and secondary defenses that maintain their disease resistance
- collection of statistical tools used to explain the associations of exposures to health outcome
- discover and establish causal (correlation does not mean causation) relationships
What are the three factors said to contibute and interact in all diseases?
Host, agent, environment
Exposure to disease causing organisms does not always mean intection occurs. It depends on what factors?***
- immune status
How does dose determine if the exposure of a disease causing orgnaims causes infection or not?
Dose: number of bacteria (or virus particles) that challenge the animal
How does pathogenicity determine if the exposure of a disease causing orgnaims causes infection or not?
Pathogenicity: organisms's ability to reach the animal, invade and infect, and multiply enough to cause disease (differences in the strains ability to invade)
What does pathogenicity relate to?
- invasiveness: the organism's ability to spread from the initial invasion site or to gain entry to the circulatory system
- production of harmful substances: pathogencity of an organism is often due to toxins or enzymes it produces that interfer with the function or metabolism of the animal
How does immune status determine if the exposure of a disease causing orgnaims causes infection or not?
immune status: the animals ability to fight off the disease organism (includes primary and secondary defenses)