Practical 4 - Eggs and newly hatched birds Flashcards
1
Q
What are the normal parameters of an egg:
A
– Shape and size of the egg
– Color of the eggshell
– The yolk material
– Layers of the albumen
– Shell membranes and egg shell
2
Q
What are the different layers of an egg, from outer to inner.
A
Shell
Outer membrane
Air cell
Inner membrane
Albumin (the egg whites)
Yolk (which is held in place by the Chalaza)
3
Q
Why is there a difference in the shape gos size of eggs?
A
Due to different species and the size caries by age, pullets age are smaller.
4
Q
Why do we examine the shape and size of the egg?
A
It influences hatchability and only standard egg can be hatched
5
Q
Often on a egg, we can see a needle point, why is that?
A
due to vaccination
6
Q
Why is the colour of the eggs sometimes different?
A
The colour varies between species.
the uterus plays a role, it is genetically determined and it varies by breeds.
7
Q
How can the uterus play a role in the colour of the egg shell?
A
The pigmentation of the shell
8
Q
What is the pigmentation of the egg called?
A
protoporfirin
9
Q
What causes the egg to be white?
A
Decreased production of protoporfirin
10
Q
What causes the egg to be green?
A
Biliverdin
11
Q
Why do we examine the colour of the egg?
A
Severe deviation from the standard color usually
results in bad hatchability
12
Q
What to examine of a yolk?
A
Colour and localization of it
13
Q
What colour is the yolk?
A
Yellow to orange
14
Q
What determines the colour of the yolk?
A
The colour depends on the feed, high fat and protein content and high IgY contents
15
Q
Where should the yolk be located?
A
In the centre
16
Q
What is the albumen?
A
the white part inside the shell
17
Q
Name the different layers of the albumen
A
Outer layer and Inner layer
18
Q
what does the outer layer of the albumin contain?
A
Thin protein
19
Q
What does the inner layer of albumin contain?
A
High viscosity protein
20
Q
What does the outer layer of albumin look like?
A
Transparent, glass-like
21
Q
What does the inner layer of albumin look like, and why?
A
Yellowish-white due to aminoacid, water and
mineral store
22
Q
What holds the yolk in the centre?
A
Chalaza
It is formed in the infundibulum
23
Q
What can a rupture of the chalaza cause?
A
Lead to embryonic death
24
Q
What is the shell membrane?
A
The layers between the albumen and the shell
25
How many layers does the shell membrane have?
Two, with air cell between them
26
What is the name of the two layers in the shell membrane?
Outer and inner shell membrane
27
When does the air cell develop?
During laying of the egg
28
Can the air cell change size?
Yes, it changes according to the age of the egg. It becomes bigger
29
What makes the egg shell hard?
Calcium salt particles
30
How many different layers does the egg shell have?
3.
Mamillary layer
Spongy layer
Outer cuticle layer
31
What is the mamillary layer of the egg shell?
Formed from calcit crystals
32
What is the spongy layer of the egg shell?
contains 94% calcium-carbonate
It determines the thickness and weight of the shell, and contain pores
33
what is the outer layer of the egg shell?
Contans glycoprotein
34
When do we examine the egg by candling and what does it mean?
Before and during hatching.
We hold the egg up to a light, so we can see through.
35
Why do we examine the egg before hatching?
To determine hatchability
36
Why do we examine the egg during hatching?
To determine the fertility
At the end of the hatching period, we remove the eggs that contain dead chick embryos
37
Outer paramteres to be examined before hatching:
– Shape
– Size
– Color
– Incidental deformities
– Contaminations
– Injuries
– Size of air cell
38
Name some abnormal shapes of an egg:
– Spherical
– Extremely elongated
– spindle-like
39
What can cause an egg to have an abnormal shape?
- Inbreeding
- Too early breeding
- Infectious disease such as egg drop syndrome and Infectious Bronchitis
40
What can cause an egg to have a smaller size than normal?
The layers are too young or too old, there could also be a severe dietic problem.
41
What can cause an egg to have a larger size than normal?
Too much protein can cause very big egg, it its only relative big it can indicate the geese has been taken in to breeding at a too young age.
42
If there is blood on the egg shell, what can that indicate?
Rupture of the vaginal mucosa
43
What kind of alterations of the colour in egg can we see?
Pigmented egg or alteration in colour pattern or missing pattern
44
what is hypopigmentation?
Hypopigmentation is caused by an infectious disease, and occurs at the ned of the hatching period.
45
How many incidental deformities of an egg do we know?
Maldevelopment of the eggshell
Irregular eggshell
46
Maldevelopment of the eggshell, name examples:
skin-shelled egg
irregular and roughened eggshells
47
What causes skin-shelled egg?
EDS (Egg drop syndrome) and inadequate mineral supplementation
48
what causes irregular and roughened eggshells?
Called "wrinkeled" eggs.
Caused by a a coronaviral infection
49
What causes irregular eggshell?
Chronic inflammation in the uterus
50
Name inappropriate nestes:
Too small, too few, high salt content in the feed, low quality litter
51
Why are duck egg always dirty and can cause contamination?
the ground of the yard + water = „mud” and the mud is spread with the legs.
52
What can cause injuries to the egg?
– Nest problems / the slope of the cage floor
– Dietetic problems – vitamin D, calcium supplementation
53
What type of injuries to the egg is often seen?
Fissures or depression.
54
What is important to prevent injuries?
Thickness of the shell
55
How can we examine the size of the air cell?
With candling.
56
If the size of the air cell is increased, what does it indicate?
the air cell refers to the age of the egg, if it is increased, it could be a result of storage problem such as humidity.
57
What can cause embryonic death in the first trimester?
- Problems related to the parent flock
- Problems during egg building
- Problems during storage
- Technical problems during hatching
- Diseases
58
What type of Problems related to the parent flock can cause embryonic death?
Genetic defects
59
What type of Problems during egg building can cause embryonic death?
– Vitamin deficiency
– Inadequate calcium supply
– Mycotoxins
60
What type of Problems during storage can cause embryonic death?
– Temperature
– Humidity
– Turning during storage
61
What type of Technical problems during hatching can cause embryonic death?
62
What type of diseases can cause embryonic death?
Mycoplasma iowae
Viruses, bacteria (fungi)
63
What will cause a mixed rottening of a dead embryo?
– Effect of mycotoxins
– Thin content in the egg
– Rupture of the yolk membrane
– Mixed content
- Overgrowth of bacteria
64
If there is an overgrowth of bacteria, what is produced and what happens to the egg?
hydrogen sulfide is produced
We can see:
» Color change
» Odor
65
How do we examine a dud egg?
- External examination
- Open at the air cell; Where the beak is
- Opening the membranes
- Examination of the egg content
66
What is a dud egg?
Egg that hasn't been hatched due to dead chick or it was simply not fertilized.
67
During the external examination, what do we look for around hathicng?
We look for any opening on the shell as sign of hatching
68
When examining the content, what do we do?
Examine the membranes, the yolk and we dissect the embryo
69
During examination of membranes, what do we check for?
Presence of faeces and the state of blood vessles
70
During examination of yolk, what do we check for?
If it is absorbed or not, and the change in quality
71
what type of pathological lesions can we see on the emrbyo?
- Edema and hemorrhage on the neck
- Shortening and deformation of the leg bones
- Beak problems
72
What can be a cause of Edema and hemorrhage on the neck?
* Low temperature in the hatchery
* Mycotoxins (in the feed of the layer)
73
What can be a cause of Shortening and deformation of the leg bones?
Lack of biotin
74
What can be a cause of beak problems?
Genetic factors and mycotoxins
75
How old is the bird if we say newly hatched bird?
Hatching-10 day old
76
How can we recognize the different species?
Weight
Constitution
Shape of the head, the beak and special structures on the head such as comb or wattles
77
How do we examine the newly hatched birds?
– Bodyweight, state of development
– Skin, orifices, beak
– check the navel
– Dissection
78
Name diseases that is commonly seen in newly hatched birds:
- „Mushy chick” disease
- Starving/thirsting
- Spread leg syndrome
- Respiration exsiccosis
- „Gout” in day-old birds
- Bezoar in the gizzard
- Technopathies
- Ulcer in the proventriculus
- Rickets
- Salt poisoning
- Carbon monoxide/dioxide poisoning
- Duck viral hepatitis
- Bacterial enteritides
- Air sac and pneumomycosis
79
What is another name for muschy chich disease?
Omphalitis
80
What is Omphalitis?
It is a noncontagious infection of the navel and/or yolk sac in young poultry
81
what causes omphalitis?
Non-infectious causes could be due to inadequate nutrition of the layer flock, bad egg handling or errors during hatching
82
Pathological findings of mushy chick disease?
– Bodyweight, fat depots
– Unhealed (open) navel
– Inflammation of the yolk sac
83
What is the spread leg syndrome?
One or both legs slip out to the sides making them unable to stand or walk
84
What is the cause of Spread leg syndrome?
It is not known, could be due to slippery floor, humidity.
85
Clinical symptoms of Spread leg syndrome:
Unsteady chicks and the legs are spread.
86
Pathological finding of Spread leg syndrome:
No pathological lesions seen, but in histopathology we see dystrophy of the leg muscles
87
Name Technopathies of newly hatched birds
Wet feathers
Cooling off
Causing no thermoregulation
88
What is respiration exsiccosis?
Insufficient intake of air
89
Who is more prone to develop Respiration exsiccosis?
Pheasant and tyrkeys, on day 1-4
90
What cause Respiration exsiccosis?
High temperature and low humidity
91
Pathological findings of Respiration exsiccosis:
* Decreased bodyweight
* Sunken eyes
* Dry, sticky subcutaneous connective tissue
* Less blood
* No time for kidney lesions
92
Pathological findings if the bird was starving:
No food in the crop and/or gizzard
93
Pathological findings if the bird was thirsting:
* Sunken eyes
* Wrinkled skin on the legs
* Dark brownred skeletal muscles
94
What causes "gout" in newly hatched birds?
- Degeneration in the kidney during hatching
- Cold during transport
- thirsting that wasn't lethal
- Viruses
95
What causes Degeneration in the kidney
during hatching?
Vitamin A deficiency and mycotoxins
96
Pathological findings in case of "gout" in newly hatched birds:
Urate deposition and kidney lesions
97
What is Bezoar in the gizzard?
It is a tightly packed collection of partially digested or undigested materia
98
What causes Bezoar in the gizzard?
If there is no fibres in the feed and they start to eat the litter straw
99
Pathological findings of Bezoar in the gizzard:
* Pseudoconcretion in the gizzard
* Exsiccosis
* Starving, emaciation
100
Who is more prone to develop Ulcer in the proventriculus?
Species that are more stress sensitive
101
What causes Ulcer in the proventriculus?
– Stress
– Does not eat
– Bleeding
– Hydrochloric acid causes erosions n the border of the proventriculus and gizzard
102
Pathological findings of Ulcer in the proventriculus:
* Anemia
* Blood in the lumen of the stomachs
* Melena, black content in the colorectum
103
How can stress cause Ulcer in the proventriculus?
Histamine is increased, causing erosion/ulcer. If they erupt they will cause bleeding and we have Posthemorrhagic anemia
104
What is salt poisoning in newly hatched birds?
caused by ingestion of excessive amounts of salt
105
What is the cause of salt poisoning in newly hatched birds?
Too big salt crystals
106
Clinical symptoms of salt poisoning:
central nervous symptoms
107
Pathological findings of salt posoning
– Necrosis in the cerebellum, malatia
– Edema of the meninges
108
What is Carbon monoxide/dioxide poisoning?
induces breathlessness – a subjective distress in breathing known as dyspnea
109
What causes Carbon monoxide/dioxide
poisoning?
* Malfunctioning heating system
* Inappropriate exhaust
110
Pathological findings of Carbon monoxide/dioxide
poisoning:
* High mortality
* Hyperemia-edema in the lung ONLY
111
What is the duck viral hepatitis?
It is an acute infectious disease affecting young ducklings. It is associated with high mortality and characteristic liver lesions
112
What causes Duck viral hepatitis?
- Picornaviridae
– Astroviridae
– Hepadnaviridae
113
How is the bird infected with Duck viral hepatitis?
Excreated via faeces, infected orally.
114
Clinical signs of Duck viral hepatitis?
Ataxy, opisthotonus (central nervous symptoms)
115
Pathological findings of Duck viral hepatitis?
yellow liver with hemorrhages
Cholangiohepatitis, liver dystrophy
116
What is Bacterial enteritides?
Bacterial infection of the GI-tract
117
What causes Bacterial enteritides?
Proliferation of coliform bacteria in the water
118
How does the bacterual enteritides occur?
It is rarely independent, its often due to inadequate hygiene of the drinker and too high temperature
in the stable.
119
Pathological findings of Bacterial enteritides:
Acute mucoid enteritis
120
What causes pneumomycosis?
Mouldy litter
121
The pathogenesis of pneumomycosis:
We have mouldy litter and the bird inhales the dust through the spores causing a serous inflammation. After some days we have granuloma formation.
