Avain Fertility Flashcards
what farm factors affect fertility
breeder nutrition
breeder health
mating activity
flock age
- there are no hatchery factors
how do you calculate fertility
- number of fertile eggs/ number of egg sets X100
farm factors that affect hatchability of total set eggs
farm factors:
- fertility
- egg handling and sanitation
- egg storage
hatchery factors that affect hatchability of total set eggs
- incubator/hatcher management
- egg handling and sanitation
- egg storage
- chick handling
how do you calculate percent hatchability
number hatched/number of egg setX100
how do you calculate hatchability of fertile eggs
% of fertile eggs = number hatched/ number of fertile eggs setX100
fertility assessment of individual bird
- duration of fertility - numbers of days after a single insemination that still results in a fertile egg
- onset of fertility second day after insemination
- species average duration of fertility
chicken 10-14 days (max 20) - turkey 20 days (max 60 )
- ducks and geese ( 10 days )
spiking
- the process of placing younger males in the flock about 38-52 weeks
- carried out to reverse declines in fertility due to a reduction in mating activity by over weight or poor conditions in males
- fertility increases after spiking because
- young males mate frequently and old males are encouraged to start mating again
- a minimum of 20% spiking males should be added to the flock
- some flocks will be spiked more than once
bird weight and condition for fertility
- proper weight gain in the growing period
- avoid overweight hens
health concerns for body weight
- disease
- leg issues
- general stress
sperm movement
- motility required for sperm to:
- pass through the shell gland-vaginal junction (about 15 minutes)
- enter sperm storage tubules
fertilization
- the sperm penetration of ovum and fusion with the female pronucleus within the germinal disc to initiate embryonic development
- vitelline member
- inner perivitelline layer (IPVL)
- deposited in ovary
- zona pellucida in mammals
- outer perivitelline layer ( OPVL)
- deposited in the infundibulum
embryonic development at oviposition
- first cell division starts about 5 hours after fertilization
- at 256 cells 4 hours after entering the shell gland
- embryo contains 30 000 cells at oviposition
- 2 regions present ( inner area pellucida and outer area opaca)
diapause
- the period of time between oviposition and incubation (storage)
embryonic development during diapause
- little if any development is desirable
eggs are stored below “physiological 0” - stored at 10-18C
difference between storage of table eggs and hatching eggs
table eggs:
- max 10 degrees
- max 85% humidity
hatching eggs:
- can be stored up to 2 weeks
- 1 week 16-18 degrees
- 2 weeks 10-15 degrees
70-80% humidity
- best hatchability 3-4 days
with the air cell up!
incubation period chicken
21d
- incubator 37.5C 55-60% RH d1-18
- hatcher 36-37 71-80% RH d19-21
incubation period turkeys
28d
incubation period ducks
28d
incubation period geese
30d
yolk sack membrane
- connected to the embryo midgut
- encases the yolk fully by day 5
- enzymatic capability
- unused yolk absorbed into the hatchlings abdomen
amnion
- provides cushion to prevent damage
- eventually consumed by embryo
chorion
outer membrane in contact with the inner shell membrane
allantois
- forms between the chorion and amnion membranes
- embryonic lungs
chorioallantois
- fusion of chorion and allantois
- storage of waste products
- calcium mobilization
embryonic development
- tissue development
- small blood vessels apparent
- posterior part, neural tube, heart formation, cephalic bud
- allantoic vesicle, posterior limb bud, anterior limb bud, eyeball with lens
5, cephalic bud, eye, lower limbs, upper limbs - beak is visible, some voluntary movements apparent
- beak and egg tooth is visible, some some voluntary movemnts apparent
- feather tracts apparent
- mouth opening apparent
- egg tooth prominent, toe nails appear
- tail feathers apparent
- toes formed, feathers apparent
- scares on legs appear, body covered with feathers
- embryo turns head towards large end
- gut is drawn into heay bpdu cavity
- feathers cover body, albumen mostly used up
- head tucked betweem legs amnionic fluid disappears
- embryo is full sized, head is tucked under right wing, yolk sac is outside of body
- yolk sac is mostly drawn into the body
- yolk sac within body cavity, internal and external piping, lung respiration apparent
- chick emerges from shell
hatching
- embryo draws yolk sac into body cavity
- embryo orientation, head under right wing, lying under air cell
- begin pulmonary respiration
- pipping
- pushes legs to exit shell
eggs transferred to the hatchery
- egg placement on side enables chick movement at hatching
- egg sanitation
- clear eggs can be removed by candling
- moving process allows for in ovo vaccination
in ovo vaccination
- 18.5 days into incubation
- commercially used since 1992
- target is either amnion or embryonic
egg candling
- candling is when you shine a light through an egg to detect for development in the embryo
clear eggs
infertile
blood ring
embryonic mortality
