LECTURE 1: Evaluating a Sick Flock Flashcards
* study ammonia cycle (slide 18)
Half of the time what is the major cause of disease?
Management
What are the 3 points of the epidemiological triad?
- Agent
- Host
- Enviornment
For poultry how does the epidemiological triad really look?
The environment acts as a fulcrum in which the agent and host sit and balance on
What are the top 3 reasons the poultry vet is called?
- Elevated mortality
- Decreased feed/water intake**
- Low fertility
What disease is driven by a loss of feed/water intake?
AI
There is an ______ level of mortality in any form of animal production.
Expected
What are 3 factors that effects the levels of “accepted mortality” in birds?
- Breed/Strain (Genetics)
- Housing Type
- Age of the Animal
What housing system is the mortality the highest for layers?
Cage-Free
Each poultry sector has ______ causes of normal mortality? What does this mean?
Typical
You have normal expected causes of mortality, it is expected.
Mortality is generally counted in…..
Why is this used?
Birds/1000/Day
Give a threshold as to when you should investigate for a disease.
For layers how is mortality generally accounted for different from broilers and turkeys?
%/1000/Day
Why do you need to know a history about the farm that you know?
You need to know what you are working with, you need to know what the “normal” looks like or if the flock has a history of disease.
What are 3 key factors that effect what is normal physiology wise?
- Body Condition
- Feather Quality/Quantity/Staining
- Comb
What are 2 key factors that effect what is normal behavior wise?
- Scratching
- Vocalizing
What is formalin for?
Fix the tissues to the point where they can be trimmed, cut thin, and put under a slide to look at under a microscope
Tissue microscope analysis is called what…..
Histopathology
What is special about formalin?
Does not work well when its cold.
Why is an ammonia meter important?
Because you eventually become nose blind to ammonia and by the time you notice it, it is already above the levels it should be
What is the use for an infra-red temperature gun?
Looking at litter temperature and evaluating chick, duck, poult placement
Why would you use pH indicator strip?
People use water line sanitizers that work only at certain pH levels, you can use pH indicator strips to test if its working
Birds maintain drinking until what pH?
4
What does F.L.A.W.S stand for?
- Feed
- Lighting and Litter
- Air Quality
- Water
- Sanitation/Staff/Biosecurity
What are the top 3 things to look for in feed?
- Formulation Type
- Quality (moisture, evidence of fungus/mold, rodent contamination)
- Quantity
Why are recent feed changes important to know when you are working up the flock?
Feed intake can be reduced when the feed is switched. Anytime you change the amount of fat/protein you are altering the gut microbiome
Pellets are ideal for what birds?
Broilers, turkeys, and ducks
Crumbles are ideal for what birds?
Young broilers and turkeys and +/- layer chicks
Mash is ideal for what birds?
Layers
What happens if feeders are too low?
Feed spillage, attracts unwanted critters
Where should the lip of the feeder fall?
Crop height
What is the purpose of “skip a day feeding” in broiler breeders?
(Fish tank analogy)
You don’t want them getting too big or too fat quick and helps majority with flock uniformity. Bottom end feeders get the feed they need.
What is the downside of skip a day feeding?
Walking the barns pulling birds out of the pans.
What is the importance of light in poultry?
- Regulation/modulation of reproduction
- Aggression
- Activity levels (birds only eat when the lights are on)
What is GAP?
Global Animal Partnership (3rd party auditing group)
Plays are role in labeling for marketing
Why is it important to measure light at bird height?
You wont get an accurate reading for the lighting of the birds if you aren’t recording lighting down or up by the birds (same goes for ammonia)
What is the importance of litter? (top 3)
- Moisture absorbency**
- Foot pad health
- Coccidia cycling
What does ammonia do to the birds?
Damages cilia (finger like projections) makes birds more prone to respiratory infections
Why can new concrete be an issue in barns and with the birds?
Concrete sweats, increased ammonia levels, burns the cornea of the birds eye and induces blindness
What is special about turkey water systems?
They will NOT drink from nipple drinkers will only drink from cups
What happens if the water lines are set too low?
Trigger nipple drinkers with body when going under then and then you get leaks
Why should you trigger the nipple drinkers when walking through the barns?
Make sure they are working and make sure the water pressure is right
How can you test for litter moisture?
“snow ball test”
Why is air quality important? (top 3)
- Thermoneutral zone (75 degrees Fahrenheit)
- Birds are dusty
- Predispose to respiratory conditions**
What is the thermoneutral zone for ducks?
55 degrees Fahrenheit
What are poultry house controllers, what are they used for?
Control housing temps and lighting
KNOW HOW TO USE BRAND
Important for accessing data
Why is water important?
- Water consumption and feed consumption
- Hydration
- Thermoregulation
What are the 3 pts of the biofilm cycle?
- Attachment
- Growth
- Detachment
Why are biofilms important to keep in mind?
Contribute vastly to disease and can be difficult to get rid of
What are 3 water sanitizers?
- Chlorine
- Chlorine Dioxide
- Peroxide Compounds
What is another S term to use in describing flaws and why is it important?
Space
Decreased space means increased disease transmission, overcrowding leads to higher stress levels, more birds more feces
What are methods to identify a disease or problem flock? (top 3)
- Monitoring and surveillance
- Performance measures (ELIZA)
- Field or lab necropsy and associated diagnostics
What is the purpose of a convalescent titer?
You get a baseline of antibodies and then measure again in 2 weeks. Second peak in anti-bodies suggesting disease challenge.
For serology what is a general guideline of how many samples needed?
20 samples
What are 3 factors that effect when to sample?
- Age of the birds
- Disease characteristics/corresponding titers
- Established regulations
What does the word “titer” mean?
Amount of antibodies/unit of blood
What is important to keep in mind when taking diagnostic samples?
Get a representative sample of the entire flock (you sometimes only measure birds easy to catch, ect.)
What is the diagonal method of sampling?
Walking diagonal and selecting birds for sampling that way, good for getting a representative sample of the entire flock.
What are 3 pros in doing necropsies?
- Fastest way to identify lesions and sample a flock
- Allows for multiple different sample types to be acquired
- More sensitive as you can direct your sampling based on lesions present
What are some cons to doing necropsies?
- If you do not know what you are doing then what was the purpose of that necropsy
- Might not represent the whole flock
- Can get contaminated samples
How many birds should you necropsy?
As many as you can
What is a good clue to the cause of death for poultry?
Distribution of mortality
Why should you not just rely on the farm team to collect deads for necropsy?
They don’t know what samples are needed for a good necropsy. If they euthanize, they will get rid of the worst birds, not a good representative of the whole flock
Why should you resubmit samples if you see differing signs?
Because birds are capable of developing multiple infections or issues unrelated to one another
