The document summarizes key aspects of the female reproductive system in birds. It discusses how birds reproduce through eggs, which develop and are laid after passing through two main parts - the ovary and oviduct. The left ovary and oviduct are functional in most bird species. Eggs develop from the ovary where follicles containing yolks mature, before being released and passing through the various sections of the long and coiled oviduct over 24-26 hours to complete formation.
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Female Reproductive System: Ovary and Oviduct
1.
2. FEMALE REPRODUCTIVE SYSTEM
Birds are unique among animals as they reproduce
through an egg .
Two parts
1)Ovary
2)Oviduct
At the time of early embryonic development, two
ovaries and two oviducts are present.
left pair develops and functional in all species of birds
Kiwis - both the left and right ovaries develop and
only the left oviduct develops
4. Ovary
The left ovary is situated at dorsal part of abdominal
cavity and the fore end of kidneys
is attached to the abdominal cavity wall by the meso-
ovarian ligament
ovary is a cluster of developing yolks or ova
At hatch, pullet chicks have tens of thousands of
potential eggs. Most of these, however, never develop
to the point of ovulation.
Each ovum surrounded by a vitelline membrane. As
the ovum develops, yolk is added.
5. The color of the yolk comes from fat soluble pigments
called xanthophylls contained in the hen’s diet.
Hens fed diets with yellow maize, or allowed to range
on grass, typically have dark yellow yolks.
Hens fed diets with white maize, sorghum, millet or
wheat typically have pale yolks.
The color of the yolks improved by marigold petals
(xanthophylls ).
6. Ovary/yolk
The liberation of ovum from graffian follicle is called
Ovulation
Ovulation occurs normally 14 to 75 minutes after
oviposition (the laying of the fully formed egg).
yolk size in the egg - up to 40 millimetres in diameter .
on the distal surface of mature follicle have a elongated
area which is free of blood vessels called as stigma, is
where the follicle normally splits to release the yolk
into the oviduct.
If the follicle splits at other than the stigma, the
numerous blood vessels will rupture and result in
blood spot in egg.
7. Occasionally the vitelline membrane is damaged and
pale spots develop on the yolk called as mottling
A high incidence of yolk mottling
use of Nicarbazin & Piperazine and dibutylin
dialaurate
cottonseed meal (gossypol) and sorghum (tannin)
A calcium deficient diet.
8. Photograph of the ovary of female
chicken, indicating the location of the
stigma on an ovum
stigma
10. Meat spots in egg white.
They are formed when small pieces of the wall of the
oviduct are sloughed off when the egg is passing
through oviduct (candling)
12. oviduct
The oviduct is a long zig zag tube (25-27 inches long)
consisting of glandular and muscular parts .
Oviduct extends from the ovary to the cloaca.
It has 5 distinct parts, viz.
1) infundibulum (9cm),
2) magnum (33cm),
3)isthmus (10cm),
4)uterus (10-12cm)/shell gland
5)vagina (12cm)
13. S.No Part Length Time spent Function
1 Infundibulum 9 cm 18 mins 1)Engulfs yolk
2)Reservoir for
spermatozoa, 3)Fertilization
2 Magnum 33 cm
(largest
portion)
2 hr 54 mins Thick white or albumen (40
%) added
3 Isthmus 10 cm 1 hr 15 mins Some albumen and inner
and outer shell membranes
are added
4 Uterus/shell
gland
10-12 cm 20 hrs 40 mins Shell (CaCo3) over the egg
(47%calcium from her
bones), pigment deposition
(Porphrin- brown color)
5 Vagina
(Muscular
portion)
12 cm Cuticle is added,
helps in expelling the egg
during oviposition
Total 74 cm 25-26 hours
15. PROCESS OF EGG FORMATION
The yolk is not the true reproductive cell
When the female attains sexual maturity (FSH)-
mature ovum inside the graffian follicle grows rapidly.
The yolk weight also increases 7 days prior to ovulation
due to the deposition of yolk material over the ovum in
(alternate layers of white and yellow)
white layer -night time
yellow layer - day time
due to the deposition of yolk, the nucleus migrates
from the centre of the ovum to the periphery and lies
underneath the vitelline membrane
16. The nucleus of the infertile egg is called 'germ
spot' and that of fertile egg 'germ disc'
The anterior pituitary - FSH - that regulates the
growth and maturity of graffian follicle
Luteinising hormone (LH) that helps to release
the ovum by rupture of graffian follicle
Ovulation
oviposition (laying of egg)
17. Albumin - Magnum
Inner and outer shell membranes & water – Isthmus
Egg shell (CaCo3)and cuticle – uterus/shell gland
The tubular and unicellular glands present in uterus
which secrete a watery fluid and added to the
albumen through the shell membranes
5 hours before the oviposition shell pigments are
added.(brown colour –Porphyrin)
laying of egg, is through the contraction of uterus.
oxytocin and vasotocin responsible for uterine
contraction and Oviposition.
22. EGG SHELL
Cuticle
Spongy or calcarious layer
Mammillary layer or matrix and pores
Microscopic Pores- 8,000-10000 per egg, distributed
unevenly over the shell surface (more at broad end
than narrow end).
Exchange of volatile compounds between the shell
membrane and cuticle.
CaCo3
23. SHELL (10 %)
calcium carbonate (CaCO3) 94-97 %,
3-6 % Organic material and Pigment
Shell strength is depend on the
content of CaCO3, Mg, P, dan vit D
Thickness: 0.2-0.4 mm
Pores: 700 pores/cm2 = 17,000 tiny
pores
Semipermeable membrane: air and
moisture can pass through that
helps keep out bacteria and dust.
Mucin : covered shell and pores
23
24. SHELL MEMBRANE
Air cell
Outer shell membrane
Inner shell membrane
Air cell is situated in between the two membranes at the
broad end
Air cell - formed as a result of contraction of the egg
contents, soon after oviposition, due to differences in the
temperatures exposed to by the egg prior to and after
oviposition
The outer shell membrane is attached to the shell.
The inner shell membrane closely surrounds the albumen
25. ALBUMEN
consists of 4 layers
Chalaziferous or inner thick white, which forms (3%)
Inner thin albumen (17%)
Outer thick firm or dense albumen (57%)
Outer thin albumen (23%) of total albumen
The chalaziferous layer -very close to the yolk
immediately surrounding the vitelline membrane
of the yolk –
This layer twists into two chords on either sides of
the yolk called chalazae, which are formed due to
rotational movement of the egg in the oviduct
26. ALBUMEN (60 %)
contain approximately 40
different proteins:
OVALBUMIN,
CANALBUMIN,
OVOTRANSFERIN,
LYSOZYM, OVOMUCIN,
AVIDIN, ETC
26
27. Consist of 4 parts: inner
thick, inner thin white,
outer thick white dan outer
thin white.
cloudy appearance due to
CO2 content.
ALBUMEN
27
28. Functions of chalazae
Chalazae - hold the yolk central position and thus
serves as an anchor for yolk
Chalazae - contain a protein called lysozyme, which
is possessing antimicrobial properties and helps to
prevent the microbial spoilage of the egg
Ageing, improper storage and microbial
spoilage makes thick albumen watery
29. YOLK
Latebra is the centre of the yolk, which is a small,
nearly circular core of light coloured fluid, which does
not completely harden on boiling
Nucleus of Pander is a cup-shaped structure, which is
an extension of the neck of latebra, connecting the
base of the germinal disc
Germinal disc located on the surface of yolk, from here
Embryo formation begins.
"Vitelline membrane" is a semi-permeable elastic
membrane, surrounding the yolk, separating the yolk
material from the albumen
31. In an infertile egg it is unicellular (ovum) and contains
haploid number of chromosomes, called
"Blastodisc". It is circular in shape, with a diameter of
about 3.5 mm and with vacuoles in it.
Where as in a fertile egg, it is a multicellular structure
having diploid number of chromosomes, called
"Blastoderm". It is oval in shape, with an average
diameter of about 4.5 mm and with no vacuoles in
it.
32. Clutches
Birds lay eggs in clutches
Eggs laid on successive days are called a clutch.
Clutch size is an individual characteristic and may vary
from 2 up to 100 eggs.
However, the normal clutch size is from 3-8 eggs.
The larger the clutch size – good layers
Small clutch size indicates an inferior layer.
33. ovulation usually occurs in the morning and almost never
after 3:00 PM.
Ovulation of a yolk for the next egg in a clutch occurs
within an hour of laying the previous egg.
and so that each day the hen gets later and later in her
timing.
Since hens do not typically ovulate after 3:00 PM, the next
ovulation is delayed until at least the next day and egg
laying is interrupted.
This delay results in the break between clutches and the
cycle repeats itself a day or so later. PHUSE
34. double-yolked eggs
This phenomenon can be related to hen age but
genetic factors are also involved.
Young hens sometimes release two follicles from the
ovary in quick succession.
36. 1. As egg cools, contents contract and air cell
formed.
2. Cuticle or bloom begin to dry.
3. Size of the pores increase.
4. Albumen gives off carbon dioxide, and carbonic
acid breaks down.
5. The white changes from almost neutral (pH 7.6)
to alkaline (pH 9.7).
6. The mucin fibers becomes watery.
Physical-Chemical Breakdown of
Egg Quality - I
37. Yolk absorbs water from albumen, swells and
become a round flabby mass.
The egg becomes an inedible product when the
yolk settles to shell and becomes attached (stuck
yolk).
Vitelline membrane brakes (mixed rot)
38. Nutrient Composition of An Egg
* Protein – 6-7 g, highest quality.
* Fat – 5-6 g, readily digestible.
* Carbohydrate – low in calories.
* Vitamins – generous quantities
except Vitamin C.
* Yolk is high in cholesterol
39. %
PERCE
NTAGE
WATER PROTEIN FAT ASH
WHOLE
EGG
100 65.6 11.8 11 11.7
WHITE 58 88 11.0 0.2 0.8
YOLK 31 48 17.5 32.5 2.0
Chemical Composition of Egg
43. Ovalbumin 54%
Conalbumin 13%
Ovomucoid 11%
Lysozyme 3.5%
Globulins (G2, G3) 8.0 %
Ovomucin 1.5%
Other protein components include, flavoprotein
(0.8%), ovoglycoprotein (0.5%), ovomacroglobulin
(0.5%), ovoinhibitor (0.l%) and avidin (0.05%).
MAJOR PROTEINS IN ALBUMEN OF TOTAL
PROTEINS (Powrie 1973)
43
Egg white contains approximately 40 different
proteins:
45. VITAMINS
Component Amount per 100 g egg
Vitamin A 190 µg
Vitamin D 1,8 µg
Vitamin E 1,1 mg
Vitamin C none
Thiamin (B1) 0,09 mg
Riboflavin (B2) 0,47 mg
Niacin 0.1 mg
Vitamin B6 0.12 mg
Folate 50 µg
Vitamin B12 2,5 µg
Biotin 20 µg
Panthotenic acid 1.77 µg
45
46. Minerals
• Iodine thyroid hormone
• Phosphorus for bone health.
• Zinc for wound healing, growth and fighting
infection
• Selenium an important antioxidant
• Calcium for bone and growth structure and
nervous function.
• also contain significant amounts of iron, the
vital ingredient of red blood cells.
46
47. Lipids in Yolk
Egg lipids are found mostly in yolk, only 0,05% is
contained in albumen.
Fatty acid content:
monounsaturated (46.5%) > saturated (37.5%) >
polyunsaturated (16.5%)
Highest fatty acid content:
monounsaturated: oleic acid (18:1) approximately
40% from lipid total.
47
48. 48
1. One medium egg contains between 4-5
grams of fat
2. High cholesterol
• ~200 mg/egg
3. High in Complete Protein (EPR=93.7%); >
milk (84.5%), fish (76%), beef meat (74.3%),
soy bean (72.8%), corn (60%)
4. Little to no CHO
5. High in vitamins & minerals
• Vitamins ADEK, some B vitamins, selenium,
iodine, zinc, iron, copper
49. Energy value of eggs
• 78 kilocalories (324 kilojoules)
Protein
• Egg protein is of high biological value as it
contains all the essential amino acids needed
by the human body.
49
50. Functional Properties of Egg
50
1. Flavor, color, nutrition
2. Foaming agent
3. Emulsifying agent
4. Aids in thickening/structure
5. Binding/coating agent
6. Leavening agent
51. FOAMING PROPERTIES
51
1. Air trapped in a liquid
2. In egg foam, air trapped
by protein.
3. Denatured and then
coagulates
4. Heat expands protein/air
• Important to souffles,
meringues, omelet, and
sponge cake.
52. EMULSIFIER CAPACITY
Egg yolk is a source of lecithin, an emulsifier and
surfactant.
Lechitin is a substance that helps an emulsion
form, or helps keep an emulsion from separating
Aplication :
• Mayonnaise
• butter sauces
• salad dressing
• Stabilizer of bakery products
• Whipped egg
52
53. Properties Application
Thickening Eggs thicken foods like custards puddings, sauces,
and creamy fillings
Leavening Souffles, sponge & butter cakes, quick breads, and
puffy omelets are leavened by eggs
Coating Meat dishes, breads, and cookies are some foods
with egg components as the base ingredients for
coatings
Binding Eggs bind other ingredients for making meat loaves,
casseroles, and croquettes
Emulsifying Eggs prevent mixture separation in mayonnaise,
salad dressing, and cream puff filling
Clarifying Tiny particles are coagulated in soups and coffee to
create a clear solution
Retarding
Crystallization
Crystallization of sugar is slowed in cake icings and
candies
53
54. ANTIMICROBIAL AND ALERGEN ON
ALBUMIN
LYSOZYME
Immunoglobulin E (IgE)
OVOMUCIN (hambat enzim tripsin)
AVIDIN:
54
55. Benefit of Egg Components
Sialic acid could prevent infection
Immunoglobulin in yolk can play a role as
antibody.
PHOSVITIN has a function as food antioxidant.
Choline: aids brain function and enhances
thinking capacity and memory. It is an important
part of a neurotransmitter that helps preserve the
integrity of the electrical transmission across the
gaps between nerves.
Lutein and zeaxanthin: contribute to improving
eye health and protecting eyes from ultraviolet
rays
55
56. Allergen in Egg
There are 4 proteins in egg white may provoque
an allergy:
- ovomucoid (11%)
- ovalbumin (54%)
- ovotransferrin (12%)
- lysozyme (3.5%)
56
57. Egg Allergy Symptoms
Egg allergy is like most food allergy reactions: It usually
happens within minutes to hours after eating eggs.
the skin - in the form of red, bumpy rashes (hives),
eczema, or redness and swelling around the mouth
the gastrointestinal tract - in the form of belly cramps,
diarrhea, nausea, or vomiting
the respiratory tract - symptoms can range from a runny
nose, itchy, watery eyes, and sneezing to the triggering of
asthma with coughing and wheezing
57
58.
59. Misconceptions About Nutritive
Value of Eggs
1. Pay more with the desired shell color for
nutrient.
2. Deep yellow yolk are higher in nutritive
value.
3. Fertile eggs are more nutritive than non-
fertile eggs.
4. Organic eggs are safer and more nutritious.
5. Raw eggs are more digestible than cooked.