animal genetics Flashcards
P= G+E
phenotype = genotype + environment
goals of animal genetics
increase profit, efficiency of production, quality of production
dna
adenosine, thymine, guanine, cytosine
gene
basic unit of inheritance consisting of a DNA sequence at a specific location on a chromosome
chromosome
one of a number of long strands of DNA and associated proteins present in the nucleus of every cell
how are chromosomes assorted
independently
definition of an allele
alternate forms of a gene
what is meiosis
cell division used in the production of gametes
what are the types of simple inherited gene expression
dominance, recessive, codominance, incomplete dominance
types of polygenic gene expression
additive gene action
horned vs polled
polled gene is dominant
how does codominance show in shorthorn cattle
roan, white, and red
what is an example of incomplete dominance
labradoodle hair
what is additive gene action
many genes are involved in the expression of a trait (quantitative traits)
differences in selection
natural selection is survival of the fittest vs artificial selection is only by human influence
what is a qualitative trait?
has discrete classes and is simply inherited
what is a quantitative trait
expression over a range of genes
inbreeding
mating of animals more closely related than the rest of the population
inbreeding depression
where recessive genes become dominant allowing for “hidden” genes to come out
outbreeding
mating less closely related individuals when compared to the average of the population
heterosis
new genes that help increase the gene pool and create more genetically fit offspring
purpose of purebreeding
concentrate genes of an outstanding ancestor in the linebred individuals
what is crossbreeding
breeding of animals of different breeds or species
what is complimentarity of traits
brangus –> heat and disease resistance of brahman and carcass quality of Angus
what is a terminal cross
crosses that are sent to market, don’t want that line to keep producing
what is feed efficiency
how many pounds of food it takes to produce 1 pound of meat
what is cloning
exact copy of desired individual
what is gene insertion
insert gene for desired trait
what is gene editing
changing an animals genes to the desired trait
where is gene insertion used
mouse + bST gene (bovine growth hormone)
examples of gene editing
hornless dairy cows or all male offspring
benefits of genetic engineering
increases yield and can decrease pesticide use and can help increase availability of medical drugs
