Chapter 2 Flashcards
It is a segment of DNA (Deoxyribonucleic Acid)
Gene
is a biochemical compound consisting of a chain of nucleotides called polynucleotide.
DNA or Deoxyribonucleic Acid
Store and transmit information from cell to cell (mitosis) and from parent to offspring (meiosis)
Gene
Copy or replicate itself with great consistency and precision
Gene
•Undergo mutation or error in copying which would subsequently copied and replicated
Gene
Number of chromosomes in Chicken
78
Number of chromosomes in Duck
80
Number of chromosomes of turkey
82
This inheritance level is expressed by the so-called _______.
heritability
Pure lines are primarily developed by use of _____ _____ _____
Closed Flock Selection
Examples of Physical characteristics with high heritability
Comb type
Body shape
Plumage color and pattern
Shank
Skin color
Examples of productive traits with high heritability
Body weight
Growth rate
Feed consumption
Dressing percentage
Egg size and egg quality
Example of Biological fitness with low heritability
Livability
Morbidity
Examples of reproduction with low heritability
Egg production
Fertility
Embryonic livability
Hatchability
a selection procedure to find the lines with the best combining ability
Reciprocal recurrent selection program
The end products are generally originating from 4 different lines. This is called a _ ___ ____
4-way-crossing
Majority of breeds used today by commercial poultry keepers are _____ that have been bred by the large-scale international poultry breeding corporations and fertile eggs, DOC, or parental breeding stock are usually imported to tropical countries.
hybrids
can be classified depending on whether it is aimed to increase homozygosity or heterozygosity.
Breeding System
what are the 3 types of breeding system
Random Mating
Inbreeding
Outbreeding
Normally used in breeding experiments to minimize genetic changes in a control population wherein selected populations are controlled.
Random Mating
- this means each possible mating in a population has the same probability or occurrence.
Random Mating
- mating between individuals which are more closely related to each other than the average relationship between all individuals in a population. It can be consistently carried out for several generations.
Inbreeding
- Mating between sibs and parents and progeny. Full sib mating and backcrossing of the progeny to the younger of the parents are often practiced.
Close inbreeding
Types of Inbreeding
Close Breeding
Strain Breeding
Line Breeding
- Developing a small group of animals within a breed and variety with a special character in view. This is a mild form of inbreeding.
Strain Breeding
- inbreeding with an ancestral line and is the most intensive form of back-crossing, where backcrossing to the same parent for several generations in succession.
Line breeding
- opposite of inbreeding. Mating of animals that are less closely related.
Outbreeding
Mating between strains or inbred lines are the forms of ________.
outbreeding
Two different populations are crossed to produce a first filial (F1) generation.
Single or 2-way cross
- In this method, F1 crossbred females (AB) are mated to males of a third line (C), to obtain a F2 progeny (ABC)
Three-way cross
is defined as the pairing of a male and a female for the purpose of reproduction or production of young ones.
Mating
4 Methods of Mating
Pen Mating
Flock Mating
Stud Mating
Artificial Insemination (AI)
– the usual method of pedigree breeding of chicken to segregate a single male with a group of females for the period of breeding season.
Pen mating
– several males to females ; system by which two or more roosters go with the hens in the pen.
Flock mating
– males are penned and females are brought to them after every 3 eggs lay; usual procedure to have a male confined at all times to individual pens and female will be introduced,
Stud mating
- is the technique by which seminal fluid (semen) of male is introduced or deposited into the female reproductive tract by a pipette.
Artificial Insemination (AI)
It is a red wild chicken that is widely spread in the East-Java, Burma, Thailand and Sumatra
Red Jungle Fowl (Labuyo)
Gallus gallus or Gallus bankiva
it is pale gray wild chicken that is widely spread in South and West India.
Gray Jungle Fowl
Gallus sonnerati
It is a wild chicken found in Sri lanka.
Ceylon Jungle Fowl
Gallus lafayeti
It is a Javanese wild chicken that is widely spread on the Island of Java and lesser Sunda Island.
Java or Green Jungle Fowl
Gallus varius
– widely believed to be the most probable ancestor of the modern chicken.
Red jungle fowl
Factors in the Development of Modern Breeds
- Genetic Mutation
- Selection
2 Types of Selection
Natural selection
Artificial selection
– the interference of man in achieving certain goals and personal ideals in improving the chicken for meat, for eggs, for fighting cocks, for fancy feathers
Artificial selection
– a group of chicken that were developed in common area
Class
– a group of chickens (fowls) possessing certain conformation or shape of body that distinguishes them from other chickens.
Breed
– a group of chickens within a breed that have the same plumage color and type of comb.
Variety
– a group of chickens within a variety of a breed which has undergone constant specific selection for certain traits by a specified breeder for periods of about 5 to 8 years.
Strain
The existing breeds of poultry are classified into 2 ways:
- Economic/ Utility Classification
- Standard Classification
Types in Economic/ Utility Classification
1, Egg type
2. Meat type
3. Dual Purpose type
4. Fancy class
5. Fighting class
Different Standard Classification
American Class
Asiatic class
English class
Mediterranean class
Chicks should have uniform size and color and in case of broiler chicks should not be less than ___ grams at day-old.
33 grams
