Genetics and Breeding Flashcards
mare effects on phenotype
uterine environment
milk production
temperament
what factors impact phenotype
genetics
environment
T/F genetic progress decreases as selection pressure(# of traits selected for) increases
TRUE
average generation interval of horses
10 years
T/F temperament and conformation have been found to be highly heritable
TRUE
environmental effects
feed and hay
facility/arena
trainer
judges
event cattle
what environmental factor has the biggest impact for growing horses
feed and hay
what sire has a higher correlation of navicular syndrome in his offspring
Zippo Pine Bar
all major sires can be traced back to which top sire
Three Bars
mating systems
inbreeding
inbreeding depression
linebreeding
outcrossing
crossbreeding
what signifies something as inbreeding
inbreeding coefficient > 10%
successful example of inbreeding
wimpy P-1(comes from old sorrel)
inbreeding depression
expression of recessive genes for individual characteristics
major sire of HERDA
Poco Bueno
what is HERDA
recessive genetic disease leading to skin issues that will eventually cause death
goals of linebreeding
-inbreeding coefficient less than 10%
-relationship coefficient greater than 25%
outcrossing
-mating animals in same breed but no close genetic relation
-breeding population isnt closed
-minimize level of inbreeding
goals of crossbreeding
heterosis(hybrid vigor)
T/F heritability estimates for racing decreases as race length increases
TRUE. longer races allow for greater effects of the jockey
racing stakes low to high end
claiming(low)
allowance
stakes(high)
Speed index
measure horses relative speed under certain conditions to compare horses runs at different tracks
genetic change equation
GC= (sire SI-breed avg.) + (dam SI - breed avg.) x speed(h2) + breed avg.
polysaccharide storage myopathy(PSSM)
abnormal accumulation of glycogen as sugar stored in muscle
-autosomal dominant
glycogen branching enzyme deficiency(GBED)
mostly in QH inability to correctly store glycogen, fatal to foals
-autosomal recessive
malignant hyperthermia(MH)
stress/excitement cazn trigger muscle contraction, elevated temp, and irregular heart rhythm
-autosomal dominant
