The document provides information on the chicken industry and egg production. It discusses: 1) The domestication of chickens beginning around 3200 BC initially for cockfighting, and the modern egg industry's consolidation into a few large producers. 2) The breeding and genetics of egg-laying chickens, including the dominance of the White Leghorn breed. 3) The stages of commercial egg production from breeding to hatcheries, pullet rearing, layer housing, and egg collection and distribution. 4) Issues facing the industry like animal welfare concerns regarding cage housing and alternatives like cage-free and pasture systems.

1. Introduction to Animal Science
POULTRY
Lecture 2
Dr. Jacquie Jacob
Modified by Tony Seykora

2. CHICKENS
(Gallus domesticus)

3. Red Jungle Fowl
(Gallus gallus spadiceus)
Domestication of chickens is
believed to have occurred as early
as 3200 B.C.

4. Chickens were first domesticated
for cockfighting

5. COCKFIGHTING
It is legal to raise fighting
birds in all states, but as
of 2008 illegal to fight in
all of them.
The last three states to
allow cockfighting were:
Louisiana, Oklahoma,
and New Mexico
Trio of fighting chickens
Old English Game Chickens

6. COCKFIGHTING
If May 2010, a cocking fighting ring was
broken up in Lino Lakes, Minnesota.

7. Weight = 2 lb
Eggs/yr = 10-12
JUNGLE FOWL
MEAT PRODUCTION PUREBRED
EGG PRODUCTION

8. EGG INDUSTRY
Egyptian and Chinese records show that
fowl were laying eggs for man in 1400 B.C.

12. Ranking of States for eggs in
2008
Billion of eggs
4.Iowa 14.4
5.Ohio 7.1
6.Pennsylvania 6.5
7.Indiana 6.5
8.California 5.2
11. Minnesota 2.8

13. TABLE EGG INDUSTRY
• Industry is consolidating into a few
players:
– 1987 there were 2500 Commercial egg
producers
– In 2003, 260 companies represented 95% of
all the layers in the U.S.
• 65 companies with 1 million plus layers
– 9 companies with >5 million layers

14. Yet many people have a few
chickens in the backyard!

15. Quite the chicken coop!!

17. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY FEED MANUFACTURING
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

18. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY FEED MANUFACTURING
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

19. EGG STRAINS

20. BREEDERS
• The commercial egg industry in the U.S. is
dominated by the Single Comb White Leghorn
– High rate of lay
– Early maturity
– Good feed efficiency
– Relatively small body size
– Adaptability to diverse climates
– Lay white-shelled eggs
• The most widely demanded shell color among
consumers

21. Single Comb White Leghorn
SCWL
Single Comb
White ear lobes
Yellow skin and shanks

22. BREEDERS
• In some areas of the U.S. (e.g., New
England) brown eggs are more popular
– Rhode Island Red, New Hampshire, and
Plymouth Rock based lines

23. BREEDERS
• Following WWII some breeders turned to
methods similar to those used so successfully in
producing hybrid seed corn
– Selected inbred lines of chickens, developed by
generations of mating closely related birds, were
crossed
– The very uniform progeny were called ‘inbred
hybrids’
– System still used today

24. SEX DETERMINATION
• Sex-linked characteristics associated with
feather growth
– Slow feathering (K) is dominant to rapid
feather (k) and is sex-linked
• Example of an undesirable dominant
characteristics that has been used to advantage by
the breeder

25. SEX DETERMINATION
• Rapid feathering – • Slow feathering –
Primary and secondary Primaries and coverts are
wing feathers are longer about the same length
than the coverts

26. Parents
(Genotype) (ZkZk) (ZKW)
Phenotype - feathering Rapid Slow
Sex Male Female
Zk Zk
ZK ZKZk ZKZk Slow feathering males
W ZkW ZkW Rapid feathering females

27. FEMALE MALE
Rapid feathering Slow feathering

28. MALE

29. FEMALE

30. FEMALE

31. MALE

32. MALE

33. FEMALE

34. MALE

35. Pedigree flocks (Pure lines) Male Line Female Line
#1 #2 #3 #4
Great-Grandparents ♂ x ♀ ♂ x ♀ ♂ x ♀ ♂ x ♀
Grandparents ♂ +♀ ♂ +♀ ♂ +♀ ♂ +♀
Expansion flocks (Inbreeding) ♂ x ♀ ♂ x ♀
♂ +♀ ♂ +♀
Parents ♂ x ♀
♂ +♀
Commercial egg-laying pullet

36. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY FEED MANUFACTURING
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

38. HATCHERY
• Incubation period is 21 days
• 100 degrees F is forced air, 102 degrees F if
a still-air incubator is used
• Humidity at 58-60%. Raise to 65% as eggs
start to hatch
• Turn eggs ½ turn 4-6 times per day. Do not
turn within 3 days of hatching
• Do not help chicks out of shells

40. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY FEED MANUFACTURING
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

41. REPLACEMENT PULLETS
• Temperature at 90-95 degrees for day old
chicks and decreased 5 degrees per week.

42. • Chicks are placed on 3-4” of litter.
• Hoovers guards keep chicks close to
heat source so that they do not get
chilled.

43. • Light is controlled from 12 to 20 weeks of
age – preferred: decreasing day length
• At 20 weeks of age pullets moved to laying
house with increasing day length to
promote laying eggs.

44. BEAK TRIMMING
Beak trimming prevents canibolism later on.

45. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY FEED MANUFACTURING
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

46. Raising poultry was
labor intensive

47. Free
Range
Chicken

48. Egg production is now highly mechanized

49. Typical production curve
Lighting is increased at 20 weeks of age to 12 hours and
then increased 15-20 minutes per week to a maximum of
17 hours to promote egg production.

50. U.S. EGG INDUSTRY
BREEDERS
Hatching eggs
HATCHERY
Pullet chicks
REPLACEMENT PULLETS
Laying hens
LAYING FLOCKS
Eggs
WHOLESALERS / RETAILERS

51. Aerial view: Sparboe complex
Litchfield, MN
1
2
3
4
5 Laying houses
6
7
8
9
10
11
In-line processing
facility

52. In-line processing

53. Egg Quality
• Interior quality determined by freshness
and free from blood spots.

55. Air Cell Gauge

56. Air cell depth

57. Measuring Air Cell

58. Air Cell Measurement
Air cell gauge

59. Candled appearance of a blood spot

60. Egg Quality
• Interior quality
• Exterior quality

61. Exterior egg quality
• Cleanliness
• Egg shape
• Shell texture
• Shell thickness

62. Cleanliness
Grade A eggs must be clean

63. Cleanliness
Grade A: Clean Grade B: Moderate Grade B: Moderate
localized stain scattered stain but
covering less than covering less than
1/32 of the shell 1/16 of the shell

64. Cleanliness
1/4 1/4
1/16 1/16
1/8 1/8
1/32
1/32
Grade A: Clean Grade B: Moderate Grade B: Moderate
localized stain scattered stain but
covering less than covering less than
1/32 of the shell 1/16 of the shell

65. Cleanliness
Dirty: Scattered Dirty: Localized Dirty: Prominent
moderate stains moderate stain stain
covering more than covering more than
1/16 of the shell 1/32 of the shell

66. Cleanliness – adhering material

67. Egg shape

68. Egg shape

69. Egg shape

70. Shell texture – calcium deposits

71. Shell texture – ridges

72. Shell texture – roughness

73. Shell texture – body checks

74. Shell thickness

75. TABLE EGG INDUSTRY
• Designer eggs
– Increased omega-3 fatty acids
– Increased vitamin E
• Specialty eggs
– Cage-free
– Free-range
– Pasture-fed
– Fed vegetarian diets
– Organic

76. Egg
Innovations

78. Gold Circle

79. EGG PRODUCTS
Which egg is fresher?

80. EGG PRODUCTS
• Commercial egg drying began in St. Louis,
MO about 1880
• The first commercial production of frozen
whole eggs began in 1903
• Separated eggs were available in 1912
• The first commercial egg breaking
machines were available in 1951

81. Egg breaking equipment:
For further processing

82. EGG PRODUCTS
• Processing of egg products includes breaking
eggs, filtering, mixing, stabilizing, blending,
pasteurizing, cooling, freezing, or drying and
packaging
• Egg products include whole eggs, whites, yolks
and various blends with and without non-egg
ingredients that are processed and pasteurized
and may be available in liquid, frozen and dried
forms

83. LIQUID EGG INDUSTRY
• Beside dinner and restaurant tables, eggs
are finding their way into 50+ processed
products as ingredients.
• In 2003, 206.9 million cases:
– 60.9 million cases were further processed
– 125.8 million cases (60.87%) for retail
– 18.6 million cases (9.4%) for foodservice use
– 1.6 million cases (0.8%) were exported

84. ISSUES
AFFECTING the
EGG INDUSTRY

85. ISSUES AFFECTING EGG INDUSTRY
• Cholesterol
– Technology for measuring cholesterol content
in egg improved
• Cholesterol not as high as first believed
– Understanding of cholesterol and heart
disease improved
• It is the HDL and LDL that are important NOT
cholesterol

86. ISSUES AFFECTING EGG INDUSTRY
• Animal rights/animal welfare
– Activists groups started attacking food outlets

90. REAL WELFARE CONCERNS
• Hatchery
– Chick processing: sexing, vaccinations -
handled gently?
– Disposal of males - humane?
– Transport to farms
- time, temperature,
RH, ventilation, space,
handled gently?

91. REAL WELFARE CONCERNS
• Brooding and rearing
– Delivery and placing in cages - handled gently?
– Beak trimming - necessary?
– Space allotment - too crowded?
– Cages - too barren?
– Catching for transport - handled gently?
– Transportation to layer houses - time, temperature,
RH, ventilation, space, handled gently?

92. REAL WELFARE CONCERNS
• Layer houses
– Delivery and placing in cages - handled gently?
– Space allotment - too crowded?
– Forced molting - starvation?
– Cages - too barren?
– No nests - behavioral deprivation?
– Catching for slaughter - broken bones?
– Transportation for slaughter - time, temperature, RH,
ventilation, space, handled gently?
– Slaughter - humane?

93. ALTERNATIVE HOUSING
Conventional housing Alternative housing

94. ALTERNATIVE HOUSING
Conventional housing Alternative housing

95. Cage-free systems
Supply area Resting area
Laying area Scratch area

96. Free Range
Big Dutchman

97. Pasture poultry

98. Pasture poultry

99. ISSUES AFFECTING EGG INDUSTRY
• Environmental pollution
• Manure is typically spread on land as a
fertilizer
• High in P which can lead to pollution
of surface waters

100. QUESTIONS?