Module 6- poultry Flashcards
1
Q
photoperiod
A
period of time when a bird receives illumination = daylength
2
Q
what type of breeders are most type of birds
A
seasonal, long day
3
Q
long day breeders
A
become reproductively active as days are getting longer
4
Q
when is molt triggered?why
A
fall, they replace their plate feathers so they are ready for a fall migration
5
Q
longer vs shorter wavelength colours
A
longer-red/orange
shorter-blues/greens
6
Q
do longer or shorter wavelengths have better egg production?why?
A
longer b/c it stimulates the extra retinal receptors
7
Q
why can birds see extra colours
A
they have 1 extra cone in their eye
8
Q
light perception pathway
A
light hits photoreceptors (pineal, eye, or hypothalamus) -> takes energy from photons to convert it into a neural signal -> sent to hypothalamus -> stimulates GnRH -> releases LH & FSH from pituitary gland
9
Q
how does melatonin work in photoperiods
A
produced by pineal gland & eye which acts like a time signal to the body to help regulate the circadian rhythm
10
Q
when & where is melatonin produced
A
pineal gland & eye, synthesized at night
11
Q
T or F: melatonin is not required for birds to respond to photoperiod
A
T
12
Q
how many locations does the hypothalamus have for photoreceptors
A
3
13
Q
critical daylength in chickens
A
when photosensitivity starts & triggers bird to become reproductively active
- 11-12 hours
14
Q
commerical photoperiod
A
14-16 hours
15
Q
internal circadian rhythm occurs on a ( ) time frame
A
24 hour
16
Q
what is released when birds are photostimulated
A
LH
17
Q
what occurs if birds fail to continue to be stimulated by increasing day length?
A
GnRH is not released & birds come out of lay
18
Q
when can birds be photostimulated again after photorefractory period
A
next spring b/c need period of days to be photostimulated
19
Q
what age are birds photostimulated in commerical laying hens?
A
18/19 weeks
20
Q
T or F: turkeys have much steeper refractory period
A
T
21
Q
what age does force moulting occur
A
70-80 weeks
22
Q
why is molting birds illegal in canada
A
b/c of animal welfare concerns b/c need to take food & water away
23
Q
molting process
A
deprive feed & water, use 6 hours of light / day = stresses birds = come out of lay = can photostimulate after 2 weeks of no eggs
24
Q
what ovary is the rudimentary vs function
A
left= functional
right=rudimentary
25
what occurs if left ovary is damaged
right ovary can develop into ovotestis = cannot produce fertilized egg
26
when do oocytes begin to develop
at sexual maturity when bird is photostimulated
27
T or F: birds produce tons of follicles but only a small fraction will be ovulated
T
28
what occurs as follicles begin to mature
rich white yolk becomes incorporated = allows formation of small white follicles that develop into small yellow follicles
29
what is rich white yolk high in
protein
30
how many grams of VLDL are incorporated every day into follicles
19g
31
what happens to the remaining follicles that are not ovulated
undergo atresia
32
what type of yolks are selected to enter the follicular hierarchy
yellow, 1 per day, 5-7 total
33
what occurs when follicles are developing in follicular hierarchy
estrogen is produced = production of VLDL & vitellogenin
34
vitellogenin
transports nutrients from bird into egg
35
how many mm are follicles in diameter at ovulation
30-40mm
36
what is follicular hierarchy determined by? F1 vs F5
size, F1= biggest & next to be ovulated, F5 was smallest & last to be recruited
37
what is recruited from small yellow
large white follicles
38
T or F: large white & yellow are similar in composition
T
39
granulosis cell layer
large rectangular cells in follicles
40
what prevents materials from passing through cell layer
tight junctions
41
occludin
regulator of cell junctions
more occludin = stronger barrier = less gets through
42
effects of high activin A vs high inhibin A
activin-upregulates occludin
inhibin=downregulates occludin = less responsiveness to FSH
43
what is the key component to recruitment of follicles into hierarchy? why?
FSH, b/c primordial follicles become responsive to FSH & start to get recruited into follicle hierarchy = reduce sensitivity to FSH & switch to LH sensitivity
44
what does a defective follicular hierarchy mean? what causes it?
less organized
more than one follicle released at a time
cause- overweight in boiler breeder hens
45
T or F: twins cannot occur b/c not enough room in egg
T
46
testosterone function
stimulate comb growth & female specific plumage
47
estrogen function
stimulate separation of pubic bones & development of medullary bone
48
what can be used to indicate how close a pullet is to onset of lay
comb development
49
what is the production of the medullary bone stimulated by
estrogen
50
medullary bone
reserve of calcium
51
what 2 things can occur if a bird does not have enough calcium
osteoporosis & cage layer fatigue
52
cage layer fatigue
will not stand & will be culled
53
skeletal changes as bird becomes sexually mature
widening of pubic bones for egg to pass through
54
what bone drops down as bird approaches lay
cleal bone
55
what 2 changes in hormones occur as the follicles grow?
1) oestrogen declines
2) progesterone increases (F1 has the most)
56
what does the follicle rupture at ovulation to release the ovum into oviduct?
stigma- non-vascularized tissue
57
post-ovulatory follicle
produce prostaglandins, P1 is most recently ovulated
58
what are 3 possible functions of post-ovulatory follicles
1) recruitment of small yellow follicle into follicular hierarchy
2) triggers smooth muscle contractions for oviposition
3) nesting behaviour
59
infundibulum functions (2)
1) site of fertilization & sperm storage tubules
2) secrete vitelline membrane
60
internal infundibulum layer
malfunctioned follicles are released into abdomen instead of infundibulum
61
vitelline
outer layer of yolk, surrounds yolk to keep it separate from the rest
62
magnum function
deposits first 3 layers of albumen
- inner thick
-inner thin
-outer thick
63
chalazae cord function
helps with placement inside the egg
64
isthmus function
2 shell membranes placed
- air cell forms
65
how can old egg be indicated by air cell
more evaporated = larger air cells
66
shell gland
puts final layer of albumen down
- outer thin layer= pumps egg into outer shell egg shape
67
where does the egg spend most of its time
shell gland
68
what % of egg weight is from the shell
12%
69
what is 98% of the egg made of
calcium carbonate
70
how many grams of calcium in a 60 gram egg
7 grams
71
what do pores in the egg do
allow for gas exchange so embryo is not suffocated
72
2 layers of shell gland
1) mammillary layer: knob structures
2) spongy layer: column formation
73
T or F: shell pigment is a heritable trait & you can select for it
T
74
porphyrins
derived from haemoglobin metabolism = brown egg shell
75
oocyanin
product of bile formation = blue/green eggs
76
bird that lays blue/green eggs
araucana
77
physical vs chemical barriers of shell cuticle
physical- plugs pores to avoid contamination
chemical-proteins with antimicrobial factors
77
cuticle purpose & function
final layer that gets put into egg before oviposition- acts as a protective layer to reduce evaporation & contamination of the egg by partially blocking pores
78
T or F: older birds have less protection of their egg cuticles
T
79
CFIA egg wash instructions
pre-rinse 30 degrees C & detergent wash of 45 degrees C
80
should egg wash detergent have high or low pH
high
81
do eggs need to be washed?
yes, and need to be placed into fridge to prevent bacterial growth
82
germinal disk
part of ovum that will be fertilized
83
shell gland vagina function
similar to cervix
1) sphincter like muscle
2) major sperm storage tubules
84
after insemination, approx. 75% will contain an average of ( ) sperm per tubule
400
85
sperm host glands
folding of epithelium to form pocket to store sperm
86
where do sperm get energy from
granules cells
87
what is the function of tubules controlled by
estrogen & progesterone
- increase in progesterone = release sperm when oviduct is clear so sperm can move up to oviduct before ovulated egg moves into it
88
chickens, turkeys & quail- how long do sperm stay healthy in sperm host glands for?
chicken-2 weeks
turkey-up to 10 weeks
quail-10 days
89
cloaca
common exit for digestive, urinary & reproductive tract
90
where is the site of semen deposition
vagina
91
how does semen get deposited into vagina
vagina everts during mating to avoid it touching cloaca for sanitary purposes
92
what % of sperm deposited into cloaca will move into storage tubules
1-2%
93
what time of day does LH peak
at night = ovulation occurs following morning
94
how long does it take an egg to move down oviduct
24-26 hours
95
release of prostaglandin & progesterone during oviposition are released from
F1
96
what will occur if there if no F1 follicle to release prostaglandin & progesterone during oviposition
delayed oviposition for 1-7 days
97
male reproductive tract function
produce healthy sperm & semen and mate female birds
98
where are testes found
abdominal cavity, tucked against back
99
what temp is sperm produced
41-42 degrees (higher than body temp)- opposite to mammals
100
seminiferous tubules
store undifferentiated germ cells
101
where are the seminiferous tubules found
capsule
102
3 parts of the capsule
1) tunica albuginea
2) tunica serosa
3) tunica vasculosa
103
sertoli & leydig cells
sertoli-increase testosterone production
leydig-produce androgens
104
where do seminiferous tubules empty into
rete testis
105
rete testis
sperm maturation
106
epididymis
fertility of sperm (13%)
107
2 functions of vas deferens
1) major sperm maturation & storage
2) expels semen into cloaca through papilla
108
rete testis is ( ) in chickens and efferent ductal is ( ) in quail & fowl
higher, larger
109
T or F: birds do not have seminal vesicles, prostate gland or bulbourethral glands
T
110
paracloacal vascular bodies
forms lymph fluid so copulatory organ can work
111
semen composition
seminal plasma & lymph fluid
112
copulatory organ function & location
on floor of cloaca, tissue that gets engorged with lymph fluid to provide a path for the semen to move through
113
coprodeum
where digestive dumps into
114
proctodeum
tissue caudal to other parts
115
urodeum
where urinary dumps into
116
anseriformes
birds that mate in water so they have external copulatory organs
- have corkscrew Pisces that fit together
117
t or F; males take longer to become sexually mature
T
118
FSH vs LH in males
FSH- growth, differentiation & spermatogenic activity
LH-testosterone production
119
when males are photostimulated, testes grew ( ) & ( ) after peaking
quickly, decreased
120
T or F: migratory birds fully regress testes for most of year b/c they did not reduce weight for migration
T
121
semen characteristics
viscous & milk white
122
T or F: chickens produce more & less concentrated sperm than turkeys
T
123
sperm morphology
long & cylindrical, tapered at both ends
124
T or F: no sperm capacitation is required in birds
T
125
what influences sperm shape
b/c of sperm storage tubules- to move through oviduct
126
clutch
a period of 1 or more days of consecutive egg laying
127
prime sequence
the longest laying sequence, occurs during peak lay
128
lag
difference (hours) between laying of eggs in a laying sequence
129
longer lay times = (longer/shorter) sequences in general
shorter
130
longer lay times are the result of
slow follicular maturation
131
broodiness
evolved behaviour where hen will incubate her eggs
132
broodiness hormonal factors
plasma LH= triggers post ovulatory follicles to produce estrogen
progesterone - produced by F1
prolactin increases
133
effects of prolactin on broodiness
increase = hens cease lay & enter broody behaviour
134
how can prolactin levels increase in relation to broodiness
low photostimulation = prolactin suppresses LH, estorgen & progesterone = hen enters nest
135
T or F: follicles suppress & ovary shrinks during broodiness
T
136
environmental factors that effect broodiness
1) high temp = increases VIP
2) low light
3) isolation
4) physical contact of brood patch on breast
137
brood patch
feathers on chest disappear = allows contact with eggs or floor = stimulates broody behaviour
138
VIP
vasoactive intestinal peptide
139
why do we not want broodiness in commerical barns
b/c we want them to keep their lay as long as possible- incubators will incubate their eggs
140
how to avoid broodiness in commerical barns
1) no dark spots
2) keeping right density
3) match temp wth metabolic
4) genetic selection
141
T or F: turkeys are still a problem in commerical barns for broodiness
T
142
what medical approach can stop broody behaviour
VIP vaccination
143
effects of VIP vaccination on egg production
more eggs per hen in VIP vaccinated birds - peak in egg production was maintained (did not drop after)
144
natural mating ratio of hens to roosters
1 rooster : 10 hens
145
when does natural mating occur? why?
afternoon-based on hormones & timing of egg lay
146
cloaca kiss
rooster touches cloaca to hens everted vagina
147
how does a female display receptive behaviour
rooster hops on top, grabs feathers at neck & treads = squats & pushes wings out = tail raises = vagina everts
148
when would AI be used in the poultry industry?
turkeys & zoos to produce rare birds
149
semen collection technique
massage back of rooster in vent area to stimulate copulatory organ & ejaculation
150
why is a pooled semen sample used in AI?
prevents using 1 possible weak source to a number of hens = produce low fertility rates
151
semen extenders purpose
helps with reducing changes in pH due to bacteria
152
what does it mean if there is pink or yellow semen?
collected something else with the semen- fecal matter, blood, or other bodily fluids
153
how much semen should be collected by 1 bird?
0.5mL - of more = collected something else with it
154
how can identify sperm motility
live dead stains under a microscope- any cells that become dyed are dead cells
155
what can occur if AI is done too close to oviposition
up to 40% less fertilized eggs
156
when should AI be done
afternoon b/c hens lay in morning
157
frequency of insemination for chicken vs turkeys for peak fertility
chickens-every 5-7 days
turkeys- every 7+ days
158
can avian semen be stored & used later?
no it does not freeze well = poor fertility
159
fertility equation
(# of fertile eggs / # eggs set ) x 100
160
farm factors of poor fertility
1) overweight hen
2) diseases & leg issues
3) flock age
161
do any hatchery factors effect fertility
no
162
T or F: males reproductive activity declines as flock ages
T
163
hatchability equation
= number of saleable eggs / number of eggs set x 100%
164
farm factors of hatchability
1) egg handling & sanitization
2) egg storage
165
hatch of fertile equation
= number of saleable eggs / number of fertile eggs set x 100%
166
individual bird fertility assessment
1) duration of fertility
2) onset of fertility after insemination
167
T or F: the 1st egg after insemination will not be fertile b/c it was already in oviduct when hen was inseminated
T
168
what species has the longest average duration of fertility
turkey (20-60 days)
169
stale sperm effect
want to catch early before hens hit fertility
170
T or F: fertility drops after insemination b/c of stale sperm effect
T
171
what % of fertility is aimed with insemination
90%
172
combination of fertility & hatchafertile effects
stays more plateaued for a long time before slowly decreases
173
effect of broiler breeder flock age on fertility
24 weeks - slowly increasing in fertility b/c not all birds have become reproductively active at same time
174
spiking
process of placing 20% younger males in the flock at about 38-52 week
175
2 benefits & 2 concerns of spiking
benefits:
1) young males mate regularly & have high sperm quality
2) older males will see competition & start mating more bc of this
concerns:
1) biosecurity
2) aggression
176
how long do sperm have to make it up to infundibulum for fertilization
15 mins
177
fertilization definition
sperm penetration of ovum with female pronucleus & initiates pro-embryonic development
178
inner vs outer pervitelline layer- where are each deposited
inner (IPVL)- deposited in ovary
outer (OPVL)- deposited in infundibulum
179
T or F: more than 1 sperm can enter IPVL but only 1 sperm can fuse with female nucleus
T
180
T or F: freshly ovulated follicles only have IPVL
T
181
stage x cells at oviposition
30,00 - 60,00 cells at oviposition
182
2 regions of embryonic development at oviposition-what do they form
blastocyst has developed into 2 regions
1) inner area pellucida - embryo develops out of this
2) outer area opaca- forms yolk sac
183
diapause
period between oviposition & incubation
184
what temp should eggs be stored at during diapause
physiological zero
- 10-18 degrees C
185
humidity balance of egg storage
not too much for bacterial growth & can suffocate eggs but not too less that eggs cannot evaporate moisture
186
T or F: chickens have the lowest incubation period
T
187
humidity % for incubator vs hatcher
incubator-55-60%
hatcher-71-80%
188
why should air cell be placed upwards
for proper embryo formation
189
5 extraembryonic membranes
1) yolk sac membrane
2) amnion
3) chorion
4) allantois
5) chorioallantois
190
yolk sac membrane function
provides enzymes to break down nutrients in yolk, any remaining yolk goes into abdomen to provide nutrients after hatch
191
amnion function
holds amnionic fluid = cushion
192
chorion function
no apparent function
193
allantois function
gas exchange, acts as embryonic lung
194
chorioallantois function
chorion & allantois fusion
- forms allanoic sac for waste storage & gets calcium out of shell
195
embryonic tissues day 5, 10, 15 & 20
5- albumen & yolk
10-yolk sac starts to disappear, allantois starts to fuses with chorion
15-yolk sac 1/2 full, chorioallantois formed
20-albumen is gone, yolk sac in abdomen
196
T or F: infertile eggs have a darker coloured center
T
197
what forms first & last during embryonic development
heart & neural tube first, moves head to big end of egg, yolk sac is pulled into abdomen, internal piping then hatching
198
what occurs if yolk sac is outside of embryo body during development
prone to infection = culled
199
internal piping
pip into air cell & begin breathing with lungs
200
external piping
break into hard shell, push legs & pop out of shell
201
what day do chicks hatch
day 21
202
embryo orientation
head under right wing, lying under air cell
203
what occurs if there is no internal piping by day 19
high CO2 in egg = suffocation b/c not gas exchange
204
what day to transfer egg from incubator to hatcher
day 18
205
incubator function/orientation vs nature
egg trays move continuously on a 45 degree angle to prevent embryo from sticking to 1 side & maintaining gas exchange
nature- hens spin their eggs
206
candle eggs
take out eggs & shine light through egg & can see whats inside egg- take out any dead embyros or infertile
207
why transfer eggs to hatcher
1) enclosed trays
2) egg sanitation
208
in-ovo vaccination
give a vaccine through shell of egg at 18.5 days incubation
209
T or F: embryonic location for the in-ovo vaccine has best efficiency
T
210
what 2 diseases does an in-ovo vaccine protect against
mareks & newcastle
211
where is an in-obo vaccine injected
below air cells, perpendicular delivery
212
blood ring around egg
broken blood vessels = dead embryo
213
day 5 egg candling
distinct blood vessels are apparent
214
T or F: a mostly shadowed egg during candling means a healthy embryo
T
215
hen oviduct pathway
1) infundibulum
2) magnum
3) isthmus
4) shell gland
5) shell cuticle
