Hatchery management Flashcards
Keys to poultry success
-most concentrated bird population- huge impact of their management practices
-quality of chicks
-disease status
-Where eggs come from? Will get eggs from a few farms that will be delivered to large number of farms
What is selected for when breeding?
-Environment
-animal welfare
-economy
What birds are selected for?
- Boiler breeders (parents of meat birds)
- Turkey breeders (parents of meat birds)
- Laying hen breeders (parents of egg layers)
Egg transmitted Flock diseases
- Salmonella pullorum
- avian encephalomyelitis
- mycoplasmas
Salmonella pullorum
very high mortality particularly in young chickens and turkeys (almost 100%)
Avian encephalomyelitis
-viral disease that causes ataxia and leg weakness
-sudden 5-10% drop in egg production and 5% decrease in hatchability
Hyperimmunization of breeder hens
*provides maternal transfer of antibodies
Induction of heightened state of immunity by admin of repeated doses of antigen
-used against infectious bursal disease (B cells affected) and chick anemia virus (T cells affected)
Breeding flock nutrition
-breeder diet is slightly higher in vitamins and protein to help fortify the egg for chick development
*infertility associated with deficiency in vit A, E, selenium
*excess crude proteins might reduce fertility
*deficiencies in vitamins and minerals may reduce hatchability
Egg temperature prior to incubation
-physiological zero from 10-18 degrees within 4hrs
-collect eggs 2-4x a day
Shell quality before incubation
-examine for cracks which will result in microbial contamination (disease associated with egg shell bacteria is not egg transmitted)
Egg storage prior to incubation
-primarily on the breeder farm OR at the hatchery
Egg cleanliness prior to incubation
Dispose of excessively dirty or cracked eggs
>dirty eggs often infected
>egg explosions during incubation or hatching
>Floor eggs- hen laid them on floor
Egg storage
Relative humidity= 70-80%
Location: best at breeder’s house
Temperature: physiological zero (10-18degrees)
Duration: shorter the better; longer storage affects total hatch uniformity and performance
*1wk-14days
Recommended storage temperatures
1-3 days: 18-21degrees
4-7d: 15-18 degrees
More than a week:10-12 degrees
Egg cleaning?
Often eggs are not washed because cuticle surrrounding egg is natural way to protect it
**Cleaning in hatching= microbe destruction through spraying or washing in disinfectant
Washing turkey eggs
Often wash turkey eggs because they are often dirtier
Natural incubation
Involves brooding
**we naturally select against broodiness because when they are brooding they are not laying eggs and therefore production decreases
Mechanical incubation set up
- Setting (setter/incubator)
- Hatching machines
**Different machines separated in hatchery. Allows for reduced contamination and staggering of hatch to allow for different hatching days
Incubator temperature
37.2-37.7 degrees
Hatcher temperature
36.1-37.2 degrees
Relative humidity of incubator
55-60% RH
28-31 degree wet bulb is set
=will result in higher actual temperature
Relative humidity of hatcher
71-80% RH
32-35 degree wet bulb is set
=will result in higher actual temperature
**will reduce the RH during the last several hours
Turning Eggs during Incubation
-min 8 times per day
-maintain central location of yolk in egg to prevent adhesion to shell membrane
-keep even heat distribution
Ventilation of incubator
-individual machines and rooms are used to minimize risk of bacterial contamination
-remove CO2 and provide O2
-maintain temperature
Egg orientation in incubator
-small end down
*natural incubation=on side
Egg orientation in hatcher
Eggs are placed on their sides
Malpositions of eggs
Proper position is head and beak tucked under the right wing. Typical location allows for the beak tooth to peck out of air cell at large end of egg and break shell
Malpositions:
Eg. head between thighs
Eg. head in small end of egg
What happens in between the incubator and the hatcher?
-in vivo vaccinations
When are eggs placed in hatcher?
Days 19-21
-placed in baskets which allow them to hatch and move around freely
Hatch removal
-2% of chicks should be damp
-don’t want them to be dry because they may overheat, and be exposed to bacteria
Incubator and hatching length for chickens
Incubator: 18 days
Hatcher: 3+
Total: 21 days
Incubator and hatching length for turkeys
Incubator: 25 days
Hatcher: 3+ days
Total: 28 days
Incubator and hatching length for duck
Incubation: 25 days
Hatcher: 3+
Total: 28 days
Incubator and hatching length for geese
Incubator: 25 days
Hatcher: 5+
Total: 30+
Broiler chick grading system
-check for beak defects, bloodied beak, poor feathering, mechanical pinch, large button naval/open navel (yolk is absorbed into abdomen and then should seal), open cuts on feet (meaning they sat in baskets too long)
Sanitation and disease control
-isolation
-one way flow of eggs and other materials
-hatchery design and construction
-ventilation: independent rooms, and static pressure differences to influence air flow
-egg supply quality and cleanliness is critical
Omphalitis in hatchlings
=mushy chick disease, navel infection, yolk sac infection
May be caused by egg source or poor hatchery sanitation
How can you evaluate hatchery sanitation?
-culture
-sanitation monitoring
Where is the site of fertilization?
At infundibulum
Oviposition
Expulsion of the egg from the oviduct to the external environment
How many cells does the ovary have?
30,000-60,000 cells
Fertilization
**Right ovary functional
1.Infundibulum
2. Magnum
3. Isthmus
4.Shell gland
5. Vagina
6. Cloaca
Ways to determine fertility
- Macroscopic- Open up egg to determine if it was fertilized. No incubation yet
- Microscopic- examination of fertility under microscope before incubation.
**Will see blastoderm if fertilization occurred!
Incubation test
Can test fertility.
-if it fails to differentiate= early embryonic death from infertility
**most common way to test in industry. New research for microscopic test during early incubation
% hatchability of total egg sets
-Does not indicate the reason for low hatchability (embryonic mortality or infertility)
**used in industry
Pattern of embryonic mortality
Embryonic mortality follows a pattern. Peaks at early stages of incubation, then levels, and then peaks again at end of incubation
Early: embryo development, vessels end up collapsing= blood ring
Late: high energy needed to crack open the egg or malpositioned birds. Results in late mortality
Expected hatchability
Egg/Layer breeders: 80-90%
-higher because selected for fertility traits
Broilers: 82-85%
-selected for production traits
Turkeys: 75-80%
**variability due to season, strain or bird
Reproductive performance of breeder flock
reproductive performance will decrease with flock age
Define hatching problem
- Establishing a fertility level or stage of embryonic mortality
- Hatch removal
3.Examine chicks
**all steps only conducted on a sample of eggs, either to examine a problem or as a routine method of monitoring breeder flocks
Establishing a fertility level or stage of embryonic mortality
-Candle eggs at 5-10days of incubation
-Check egg classifications: clear, dead embryo/blood ring, live embryo
Clear Egg
-infertile or early embryonic mortality (0-3days of incubation)
>differentiate infertility from early embryonic mortality
>define stage of early embryonic mortality
Hatch removal
-break out eggs that have not hatched
>define stage of mid or late embryonic mortality
Examine chicks
-note early brooding mortality of chicks on the farm
Causes of low hatchability
- Fertility
-nutrition, male to female ratio, disease, parasites, AI problem - Embryonic mortality
-egg handling and storage, improper setter and hatcher settings, disease, breeder age, nutrition, genetic factors (inbreeding) - Common incubation problems
Causes for losses in hatchability in broiler breeders
- Infertility 42%
- Early embryonic mortality 28%
- Mid term mortality 6%
- Late mortality and pips 24%
