Midterm Flashcards
mental health
state of well-being where an indiv realizes own capabilities, can cope with w/ normal stressors, work productively, & contribute to commun
animal health
absence of disease
normal physiological functioning
normal behavior
productivity (prod an)
healthy living envir
good welfare
3 circles of an welfare
physical ⟶ health & functioning
mental ⟶ affective states
natural state ⟶ nat behav
5 domains of an welfare
- nutrition ⟶ water & food access & quality
- envir ⟶ temp, confinement, shelter
- health ⟶ disease, injury
- behav ⟶ choices/limitations
all above affect
# 5. mental state: pain, thermal comfort, boredom, frustration, happiness
disease
disorder of structure or function, esp one prod specific sympt/affects specific location
- includes physc injury
envir health management
external factors impacting an health/welfare
- preventative
- human controlled
- human decisions
areas of envir health management
- general husbandry
- biosecurity
- nutrition
- housing, ventilation, & shade
- behavior needs
general husbandry practices for best envir health management
ways prod/facility staff can ↓risk of dis for indiv/group
a) avoid/minimize mixing social groups
b) ↓ stocking density
c) good access to reliable food/water
d) climate/weather control
- ex: phys changes from heat stress ↓ immune
e) preventative & reg vet exams/tx
f) waste removal
g) handling/procedures
- well-trained handlers able to identify disease sympt/behav
- poor handling ⟶ stress ⟶ phys changes
⟶ ex: pinning cats for BG test
⟶ ex: lab animals ⟶ phys changes skew data
biosecurity practices for best envir health management
protocols to prevent/minimize intro/spread pathogens
1. people:
- PPE
- facility clothes/scrubs/boots
- footbath
- showers in/out
- disinfect new equipment
2. fomites: frequently sanitize all surfaces/equipment (new & old)
3. animals:
- new ⟶ isolation & vet exam
- vx
- routine exams & dx testing
4. contaminated feed/water:
- know source
- closed/safe storage
- reg path testing
5. envir exposure:
- ecosystems an exposed to
- types of chem/phys/bio ways required of envir
- managing wildlife
nutrition practices for best envir health management
key to ensuring health/prod
- good nutr can improv health, ↓ risk dis, improv immune,
- poor nut = poor phsy cond, immune, GI, ↓ prod, welfare
housing, ventilation, & shade practices for best envir health management
- animals confined indoors need:
- reliable source of ↑quality food/water
- good waste management ⟶ breeding ground for dis/vectors
- adequate vent/humid control:
- ex: chx: >80% hum ⟶ excess
moisture ⟶ wet litter ⟶ skin
infx/lesions = foot pad
dermatitis
- ex: chx: >80% hum ⟶ excess
soln: ↓ stocking density, improve vent/hum control, litter material, ↓water = ↓ urine
- animals liv outdoors/outdoor access:
- ↑ risk accidents, predation, dis, death
- protection from envir/ elements necessary ⟶ partial/full shelter
- ex: heat stress in cattle
- adequate access to food/water
behavioral needs practices for best envir health management
behavior changes/stereotypies indicative of poor health/welfare
- behav manifestations
- important for identifying
- ex: parasitic eye fluke & rainbow trout
solution:
- add behavioral assessment to clinical exams
- limit handler influence
- assess animal under natural housing conditions: O vid of natural vs concerning behaviors
housing influences on health
species & indiv-specific housing necessary ⟶ chronic stress & ↓ immune fx ⟶ ↑ risk of dis
ways of improving envir
envir enrichment provides captive anim an opportunity to perform highly motivated species-specific behaviors
- supervised testing necessary
- ex: FB
genome to phenome
genetic-phenotypic connection
humans select traits for:
a) food: ↑ prod an mass/output helps global food security
b) ag sustainability: ↓ land/water use, ↓ GG
c)↑ fitness ⟶ more resilient to CC, dis, pests
d) consumer/O needs
- lean/healthier meats
- pet breeds
AMR
antimicrobial resistance: one of biggests threat to global health
pathogens mutate & no longer respond to meds ⟶ infx hard to treat ⟶ ↑ risk dis spread, severe I’llness, death
antimicrobial
antibiotic
med inhibits growth/destroys microbe
antimicrobial for bacteria
major uses of animal abx
- growth promotion:
- indoor intensive livestock facilities
⟶ ex: pigs & poultry
- low sub-therapeutic dose
- in feed/water
- thought to decrease GI bac ⟶ more food = more energy to grow - prophylactic
- reg therapudic dose
- preop: injury ⟶ 2h prior to op
- periop: 2h prior surg ⟶ completion (best)
- postop: completion ⟶ recovery
- all species: companion, lab, livestock, aquaculture - treatment for clinically diagnosed
- clinical signs: observable symptoms
- DVM dx
- control infx & ↓spread
economic goal of food prod
large farms w/ max livestock best for feeding huge pop w/ minimal effort & cost
food prod styles
intensive
- ↑ farms/barns
- ↑crowding = ↓space
- no outdoor access = ↑ risk & spread
semi-intensive
- smaller farms/barns
- ↓ crowding = ↑ space
- some outdoor access
6 degrees of one health
all living org are ≤6 steps from eachother
systems approach
non-traditional proactive approach to complex world health issues
- no boundaries
- often uncertainty
- transdisciplinary
1) focus: understand dis/health = comlpex
2) cause: complex interactions; mult factors
3) treatment: multifactoral, multimodal
4) approach: holistic, broad
challenges to a systems approach
- diff to solve specific problems alone
- costly & time-consuming
- relies on new treatments/philosophies
traditional approach to health
biomedical
1) focus: physical aspects of illness
2) cause: external factors ⟶ disease beyond indiv control
3) treatment: healthcare providers ⟶ diagnostics ⟶ meds & surgery
4) approach:
- reductionist
- examine indiv parts, not whole
- mechanistic
- inflexible
- body ⟶ organs ⟶ cells
challenges to traditional approach
- costly
- does not always address cause
- ignores external factors
- rewards procedures over process
consequences of abx overuse
AMR
1) abx ⟶ expensive ⟶ raise $$ an prod
2) AMR ↓ avail abx treatments for infxt prod an ⟶ ↑ death/$$
3) poor welfare
4) zoonotic transfer
ex of AMR
1) cattle fed chlortetracycline ⟶ salmonella
2) swine dysentery from Brachyspira hyodysenteriae in pigs
- esp intensive farms
alternative approaches ↓ AMR
management strategies:
1) ↑ biosecurity measures
- isolation & vet exams for new arrivals
- isolation for infxt indiv
- regular health checks for livestock
- PPE
- ↓ stocking density ↓ transmission
2) ↓ stress
- transporting
- overcrowding: ↓ stocking density
- sudden changes: diet, temp, abrupt weaning
- mixing social groups
- poor stockmanship/rough handling
**for lab: physiological effects skew data ⟶ incorrect results for scientific research = potentially harmful for humans
⟶ soln: cup method
- painful procedures w/ no anesthetic/analgesic
3) waste management, hygiene, & sanitation
4) health plan ⟶ vx program
5) improve detection
- better training on clinical symptoms of dis & reg behaviors & subtle changes
- early detection ↓ transmission & dis easier to treat/cure/manage
- precision livestock farming
- definitive diagnosis
ex: culture & sensitivity: swan infx area
⟶ culture: lab analyze to identify path
⟶ sensitivity: test existing abx in lab to see affects path
⟶ for aggressive, lasting infx or no tx effective or new infx
⟶ ↓ use of broad-spectrum and & focus on best/most effective one that treats faster
⟶ con: results take a couple days ⟶ ↑ transmission time
strategies must be shaped around indiv, facility, species, circumstances
- limitations can arise, ex: uncooperative O/O willingness, finances
abx should not be used to compensate for poor management
treatment > cure
WHO
World Health Organization: United Nations agency to promote health, keep world safe, & serve the vulnerable
- highest policy-setting/governing body
- 194 member-states
- create recomm/guidelines/policies that MD/DVM must follow
- report abx use
- surveillance of use & monitoring prescribing
FAO
UN Food & Agriculture Org: leads international efforts to defeat hunger
goal: achieve food security for all & ensure people have reg access to enough high-quality food to lead active, healthy lives
Global Action Plan
↓ abx use in prod an (affects humans most) ⟶ ↓ AMR
1) ↓ use in all classes of med important antimicrobials in prod an
2) complete restriction of med imp antimicrobials in prod an for growth
3) complete restriction of med important antimicrobials in prod an for prevention
4) conditional recommendation: critically imp antimicrobials or highest-priority critically important should not be used to treat prod an
exception: DVM provides evidence that drug is only tx option
OIE
World Org for An Health: monitor an dis emergence & development of animal diseases
- collaboration
- shared resources
- codes of practice
- guaranteed transparency
- WAHIS: Wold Animal Health Information Systems ⟶ portal
1. early warning system: immed management of alerts
2. monitoring syst: manage 6-monthly info updates
3. further info
medically imp antimicrobials
critically imp antimicrobials
highest priority critically imp antimicrobials
all antimicrobials used in humans
sole/limited therapy options
sole therapy for serious infx in humans
best practice statements
1) antimicrobials or combination developed for humans = critically important unless categorized otherwise by WHO
2) med important antimicrobials not currently used in prod an should not be used in future
exception: DVM gives evidence that only tx option
veterinary epidemiology
study of frequency, distribution, & determinants of health/dis in pop
applications prevent, manage, & eradicate dis
concepts applied to many fields of study ⟶ broad
multidisciplinary
“study of health/dis in animal pop”
disciplinary
multidisciplinary
interdisciplinary
transdisciplinary
disciplinary: branch of knowledge
multidisciplinary: diff disciplines work together with own knowledge
- additive
- stays within boundaries
- use existing knowledge to solve problems
- ex: applying existing human med knowledge in vet med & vice versa
interdisciplinary: integrating/combining existing knowledge from diff disciplines
- integrative
- boundaries removed
transdisciplinary: creating new intellectual frameworks/way of thinking to create new fields of study
ex: one health
Edward Jenner
- father of immunology
- first vaccine ⟶ smallpox
- variolation: infecting indiv w/ smallpox ⟶ died, infxt, 2° infx
James Lindt
- father of nautical med
- scurvy
- 1st randomized controlled trial ⟶ citrus tx
- black box epidemiology:
— unknown cause
— investigate/observe
— creative thinking
— trial/error
— research
John Snow
- doctor/anesthesiologist
- father of modern epidemiology
- epidemiology of cholera
- first to stud epid in hum/an
- specific appropriate doses
— ether/chloroform
1st Century
- ↑ dom of an ⟶ ↑ dis
- egyptian healers ⟶ vet hosp
- quarantine
- slaughter
1700s-1800s
- animal plagues
- techniques to improve an health
- farm hygiene
- improved slaughter techniques
late 1800s-1900s
- lab dx
- mass immuniz
- scient study ⟶ improved underst of path/transmission
- evidence-based med
contemporary vet med
evidence-based med
major techniques:
1. structured recording of an health/dis
2. improved analysis of dis in pop
- surveillance
- monitoring
- National/international dis reporting (OIE)
epidemiological investigation
tools/methods for invest, prevent, dx, ↓ transmission, tx an dis to understand:
- occurrence: where, when, who
- cause
- screening/dx
- assess effective tx
- prevention & prolongation of healthy life
epidemiology objectives
- investigation & control
- understanding nat hx
- creating dis-control programs
- assess impacts of dis on society
epid objective 1: invest & control dis examples
foot & mouth dis in sheep
- highly contagious virus
- divided-hooved an
- transmitted through direct contact & inanimate vectors
- spread hundreds of miles
- invest: tracing an movement & control
Contagious Bovine Pleuropneumonia: resp dis in cattle
- mycoplasma bac
- endemic in sub-saharan africa
epid objective 2: underst nat hx of a dis
- how host/agent interact/coexist w/in a comm w/ other org in an envir
- why some an get infx & others don’t
factors impacting agen: climar, envir, geo distribution - life hx cycle
epid objective 3: dis-control programs
based on knowledge about:
- prevalence
- factors associate w/ occurrence
- resources required to control
epid techniques required:
- direct action: strategies for prevention, control, & eradication
- monitoring: routine assessment in a pop
- surveillance: program effectiveness
epid objective 4: assessment of impacts on society
costs/benefits of control:
- economic loss
- imp of health to industry
- an welfare
- ex: mastitis cattle: inflammatory infx of udder & teet
⟶ control prog for 15% not 1%
vet epid in practice: bats
- Bats harbor more viruses lethal to humans than any other mammal
- Expanding agriculture to accommodate the land and resources required for increasing human populations is bringing humans into close contact with the animals, and this shrinking of distance is increasing the risk of spillover from bats to the villagers
path agents
- org that impairs norm fx
- manifests in distinguising signs/symp
- microscopic
prions: proteins causing fatal neurogenative dis
- ex: bovine spongiform encephalopathy aka Mad Cow
virus: core genetic material can only replicate inside living host
- ex: avian influenza ⟶ resp dis affecting poultry
bac: single-celled microbes
- can help/harm
- large variety
- ex: mastitis ⟶ tx abx
fungus: multicellular microbes ⟶ parasitic or symbiotic
- ex: ringworm: skin fungle infx in cattle, sheep, dogs, cats
protozoa: single-celled microbe
- free-living or parasitic
- potentially fatal
- ex: coccidiosis in chx ⟶ parasite damages intestine sys
multicellular parasites:
- helminths = worms
- arthropods attach to skin: ticks, fleas, lice
- ex: roundworms in beed/dairy cattle, sheep, goats, dogs, cats
path agent characteristics
infectivity: ability to infxt host ⟶ how good are they are
- how easy is it for them
- how long does it take
pathogeny: ability to cause dis
- not all hosts show clinical signs
- disease = path cause enough damage to show clinical signs ⟶ otherwise just carriers
virulence: degree of severity
a) low:
- longer to infxt & show clinical signs
- ↑ risk of transmission
b) high:
- kills host quickly
- severe
- ↓ chance of transmit ⟶ less time to spread
pathogens want to survive ⟶ killing host quickly ↓ their lifespan
epidemiological triad
goal: to understand, interconnect, & distrupt ≥ 1 corner
host: what types are targets
- species: not all pathogens infxt all species
- immune fx: ↓ = ↓ risk
- age: young & old most susceptible
sex, breed, lifecycle stage, nutritional status
envir: where is dis occurring
- external factors
- facility
- biosecurity
- water source
- system management
- contact w/ wildlife
- climate
- seasonality
agent: characteristics
- ideal host targets
- speed of infx
- transmission methods
- survival needs
- vulnerability
transmission
movement of path from 1 infxt an ⟶ 1 or group of susceptible in an infxt pop
modes of pathological transmission
1) direct:
- horizontal: direct contact w/ infxt
- vertical: offspring
- prevention: isolation & health checks
2) indirect
a) vehicle
- water & food
- airborne ⟶ dust, fine droplets (sneeze, cough)
- ex: Porcine reproductive & resp syndrome (PRRS)
- prevention: vx, biosec, management
b) mechanical vector: vector NOT infxt ⟶ carry agent btwn hosts
- arthropods
- ex: pinkeye (moraxella bovis)
- prevention: vx, management, bio
c) biological vector: vector is infxt, not necessarily harmed ⟶ carry agent btwn hosts
- arthropods
- ex: heartworm (dirofilaria immitus)
- prevention: vx, biosec, management
d) fomite
- ex: avian influenza
- prevention: biosec
Porcine reproductive & resp syndrome (PRRS)
- mode of transmission: indirect vehicle
- airborne
- virus
- nasal secretions, urine, feces, & other bodily fluids
- can travel up to 2 miles
- common in US & all age groups
prevention: biosec, management, vx
Pinkeye (Moraxella bovis)
- mode of transmission: indirect mechanical vector
- by flies
- common & diff to control
- painful ⟶ ulcers & blindness
prevention: vx, fly pop control
heartworm (dirofilaria immitus)
- mode of transmission: indirect biological vector
- mosquitos pick up blood infxt w/ larvae (microfilia) ⟶ larvae develops ⟶ mosquito infxts new dog
- adult worms live in heard, lungs, & blood vessels
treatment & prevention: anti-parasitic mx
avian influenza Type A virus
- mode of transmision: indirect fomite
- viruses shed in bird droppings
- veterinarians transfer virus to new farms by stepping in droppings & wearing same boots
prevention: biosecurity measures
nat hx of a dis
- stage of susceptibility: prior to exposure influenced by:
- immune fx
- age
- envir
- primary prevention
- stage of pre-symptomatic dis: after to exposure
- infxt but sub-clinical
- pathologic changes
- may always stay subclinical
- routine screening = important
- secondary prevention
- stage of clinical dis: from subclinical to clinical
- onset of symptoms
- observable changes in physiology/behavior
- tertiary prevention
- stage of disibility or recovery
prevention = best
incubation period
exposure to pathogen ⟶ evident clinical dis
latent period
exposure to pathogen ⟶ pathological changes
clinical signs vs symptoms
clinical signs: observable changes
symptoms: subjective
- assessing behavior
- interactions: avoidance/approach
- diff responses to pain
screenings vs dx testing
screenings:
- detect dis during subclinical stage
- more effecting in ↓ transmission
dx testing:
- during clinical stage
- confirming diagnoses or figuring out
levels of prevention
primary: avoiding dis development ⟶ ↑ host resistance/↑ susceptibility
- health promotion/detection
- prophylactics
- ex:
— vx
— routine screenings/exams
— biosec (PPE, hygiene)
secondary: early detection, ↓ transmission, ↑ chance of recovery/tx success
- early detection
- before clinical signs
- better economically & for ani health/wellness
- ex: yearly fecal tests
tertiary: stop/↓ dis progression & minimize risk of transmission
- avoid getting to this point
- dis established ⟶ clinical signs/symptoms
- tx & rehab
- $$ & resource intensive
- an health/welfare compromised
- ex: mastitis tx abx
temporal patterns
sporadic: occurs occasionally in population
- prevalence is 0
- mad cow dis
endemic: habitually present at expected level
- giardia
epidemic: ↑ level not predicted/expected
- avian flu
pandemic: widespread/international
- swine flu
- covid
vaccine vs vaccination
vaccine: prepared immunogenic material to induce immunity against path organism
vaccination: intentional administration of (semi-)harmless forms of path to induce specific immune response to protect against later exposure
how we take advantage of our body’s normal immune response
inside vaccines:
- micro-org ⟶ live, attenuated, inactivated, or parts
- adjuvant
- mostly in inactivated vx - preservatives: formaldehyde, gentamycin, dyes
biologic: regulated by USDA not FDA ⟶ okay for organic
types of vx
- live/modified
- killed/inactivated
- recombinant
live/modified vx
attenuated: ↓ virulence/weakened
- replicate in animal & shed to others
benefits:
- full immune response
- stimulate cell-mediated & humoral immune response ⟶ B & T cells
- memory from 1 dose = ↓ frequency
- long-lasting
safety:
- can induce dis ⟶ reversion to virulence
- may cause abortion
killed/inactivated vx
stimulate humoral immunity (antibodies)
- don’t replicate in animal
benefits:
- safer ⟶ no reversion to virulence
cons:
- require priming w/ live vx
- require refrigeration
- adjuvant irritating (granuloma formula)
- difficult to apply ⟶ must injxt every indiv parenteral
- expensive (encapsulation)
- shorter immunity ⟶ 1-2 yrs ⟶ require multiple doses for memory
recombinant vx
live vector carries gene from pathogen encoding protein of immunogenic interest ⟶ generates immunity to gene of interest (GOI) & vector
benefits:
- long-lived immunity
- very safe
- minimal/negligible secondary effects
cons:
- require liquid N storage
- must not have previous immunity ⟶ neutralizes vector immediately
- applied in-ovo, I’m, SQ (poultry)
- expensive
routes of vx administration
- parenteral: IM, SQ, ID ⟶ dip into vx ⟶ w/in skin
- mucosal: oral, nasal, rectal, ocular, vaginal
ex: spray, drinking water, gel - epidermal & transcutaneous: first layer of skin vs through skin
ex: wing web - in-ovo (chickens)
- fetal (mammals) ⟶ unheard of
vx immune system timeline
innate response ⟶ immediate
humoral response: 10-14 das after 1°
- max immune response
boosters: stimulate max response
vaccination vs immunization
vaccination ≠ immunization
- act of vaccinating does to lead to immunity
key to immunologic memory
re-vaccinate
bacterin
killed bacteria
ex:
- leptospirosis
- salmonella
toxoid
inactivated bac toxin
- requires 10-14d to develop acquired immunity
- acts as antigen
ex:
- clostridium perfrigens
- tetanus
antitoxins
horse/sheep-derived serum antibodies
- not technically vx
- passive immunization
- immediate protection
ex:
- clostridium perfrigens
- tetanus
attenuated or modified live examples
whole org ⟶ virulence is ↓ by adaptation to other host/org/envir
- bac: Brucella abortus
- virus: IBR, BVD, BRSV, PI-3
recombinants examples
live vector + insert
ex:
- HVT + VP2
- immunity against Marek’s & Bursal dis
vx failure causes
- an already infxt & incubating dis
- 10-14d
- stress/immunosuppression
- existing infx accelerated by vx
- ineffective: denatured by heat, UV, lack of cold-chain storage
- animal state at time:
- maternal antibody interference ⟶ neutralizes vx
- stress/immunosuppression makes infx easier to overcome
⟶ BDV virus
⟶ Se & Cu deficiency - pregnant ↓ t-cell fx
4. too high dose can overcome immune response
- application failure
- vx didn’t stimulate correct type of response
- antibodies (B cell response) = extracellular org ⟶ killed products
- cytotoxic cells (Tc cells) = intracellular agents
- antibodies (B cell response) = extracellular org ⟶ killed products
- new strain ⟶ vx not cross-protective ⟶ ineffective
- path stereotype diversity ⟶ wrong choice ⟶ ineffective
passive immunity
transfer of antibodies from resistant (immune) ⟶ susceptible (non-immune)
ex:
- colostral antibodies & lactogenic immunity
- antiserum
- plasma transfusion
- yolk sac
advantages of passive immunity
advantages: immediate protection
disadvantages:
- short-lived (～3w)
- expensive
- only involves 1/2 the immune response (humoral)
- interacts w/ early vx
adjuvants
immunological agent that increases antigenic response
- enhances inflammation
- prolongs antigen persistence
- delivers co-stimulatory signals
- activates cells of immune system
- steers response to Th2 or Th1
- delivers antigens to MHC classes I or II
vx strategies
exotic:
- rapid dx
- eradication
- quarantine
- compensation, stamp out, disposal
- surveillance
- biosecurity
- prevention
endemic:
- rapid dx
- control
- quarantine
- vx
- surveillance
- biosecurity
- prevention
BIOSECURITY MANAGEMENT = BEST STRATEGY
- vx comes 2nd ⟶ management tool
innate immunity
- initial discrimination between self/non-self
- non-specific
- from birth
- fast
- mediated by cells, barriers, chemicals, proteins
- pattern recognition
- no specificity
- no memory
ex:
- temp/pH ⟶ hostile envir
- barriers:
- skin
- feathers
- cilia
- mucosa
-microflora: biological metabolites that make physical layers of hostile envir
- neutrophils & macrophages
- encounter, activation, attack, & memory
adaptive immunity
- acquired
- specific
- 2nd line of defense
- slow ⟶ 4d+
- mediated by lymphocytes: B & T
- memory
- specialization
ex: - cell-mediated: T cells ⟶ thymus derived
- B cells ⟶ bursa (chx) or bone marrow derived
- antibodies IgM, IgG, IgA, IgE
immune response timeline
immediate innate: 0-4h
induced innate: 4h-4d
adaptive response: 4d+
mechanisms of innate immunity
1) barriers
- physical: skin & mucosa
- chemical: anti-microbes in skin/mucosa secretion
- biotic: normal flora on surface of skin/mucosa
- anatomic:
- BBB
- blood-placenta barrier
- blood-thymus barrier
2) humoral response: mediated by antibodies secreted by plasma cells
3) cells
- Natural killer cells
- dendritic cells
- mast cells
- phagocytes: endocytosis & phagocytosis ⟶ identify, engulf, & destroy
a) monocytes ⟶ blood
b) neutrophils ⟶ white blood cells
c) macrophages ⟶ tissue
process of adaptive immune response
1) antigen recognition
2) induction of response
3) regulation of response
- over-response can kill/damage org
