Horse Breeding: Terminology & Concepts - Crossbreeding, Hybrid Vigor, Inbreeding, Quizzes of Agricultural engineering

Download Horse Breeding: Terminology & Concepts - Crossbreeding, Hybrid Vigor, Inbreeding and more Quizzes Agricultural engineering in PDF only on Docsity! TERM 1 closed breed DEFINITION 1 pure TERM 2 register with jockey club DEFINITION 2 must cross registered TB with registered TBlive cover only! TERM 3 sport horse in 1600/1700s DEFINITION 3 cart horseswar horses TERM 4 sport horse purpose 1800s DEFINITION 4 improved roadsfancier carriagemilitary tool TERM 5 saddle horses 1900s DEFINITION 5 jumpingdressageshow driving(war motorized at this point) TERM 6 sport horse inspections DEFINITION 6 sucklingsat 3 yrs100 day test for stallionperformance and reproduction requirements for maresscore of 95 good enough TERM 7 acceptance into breed registry DEFINITION 7 conformationmovementperformance(not just on pedigree) TERM 8 composite breed DEFINITION 8 hybrid with at least two and typically more breeds in its backgroundmated intersestill retain a level of HV generated in crossbreeding systemsdo so without crossbreeding TERM 9 morab DEFINITION 9 can be up to 75% or down to 25% of morgan or arabiancan be F1 cross TERM 10 hybridization DEFINITION 10 donkey crossed with horse = mule or hinny TERM 21 simplicity DEFINITION 21 crossbreeding systems should be kept relatively simpleexpensive systems often fail TERM 22 crossbreeding systems DEFINITION 22 specific/terminal sirerotational TERM 23 rotational crossbreeding system DEFINITION 23 spatial rotation: same time diff placesrotations in time: diff timesfemale replacements produced within systemfemales rotated among males TERM 24 specific/terminal sire system DEFINITION 24 maternal-breed bred to paternal-breedoffspring well suited for market, sold as slaughter animalsnot retainedoften retain 100% HVvery effective choice and use of sire and dam breedsoffspring consistentneed to raise/purchase replacement females= difficultyneed replacement males for first crossless simple if replacements raised TERM 25 spatial rotations DEFINITION 25 reatain reasonable amnt HV but some lost to backcrossinglittle use of breed complementarityproportion of ancestral breed variesperformance inconsistentreplacement females within systemmore complex with more breeds TERM 26 rotation in time DEFINITION 26 sires used in sequence or temporallylose HV using same breeds (backcrossing)breed complementarity not well usedvariation in offspring, not very consistentsimple to use bc only one flock/herdsimpler than spatial rotation TERM 27 hybrid vigor DEFINITION 27 difference between the average performance of crossbreds and the average performance of their purebred parent lines or breedsunits = trait measurement TERM 28 percent HV DEFINITION 28 use percentage TERM 29 individual HV DEFINITION 29 directeffect of gene combination value in an individual itself TERM 30 maternal and paternal HV DEFINITION 30 effect of GCV in a dam or sire on performance of its offspring TERM 31 retained HV DEFINITION 31 HV remaining in later generations of hybrids that is in generations subsequent to the first cross F1usually expressed as proportion of the max HV (from F1) TERM 32 predicting HV DEFINITION 32 populationexpected from particular cross/matingcalc based on breed composition of the sires and dams mated and an estimate of HV in the F1 TERM 33 total HV DEFINITION 33 individual, maternal, and paternal HV are additive TERM 34 degree of backcrossing DEFINITION 34 the proportion of an offspring's loci at which both alleles of a pair trace to the same ancestral breed or line TERM 35 inbreeding DEFINITION 35 mating of relatives (more closely than average)increases homozygosity TERM 46 negative assortative mating DEFINITION 46 produce intermediate individualsdecrease genetic variation (bad)increase phenotypic variation (good) TERM 47 corrective mating DEFINITION 47 breed undesirable trait to exceptionally good trait TERM 48 mating to produce particular gene combinations DEFINITION 48 choices who to mate to whomcreate homozygous genotypescreate heterozygous genotypesepistatic combinations TERM 49 net merit/ aggregate breeding value DEFINITION 49 BV of an individual for a combination of traits TERM 50 multi trait selection approaches DEFINITION 50 tandem selectionindependent cullingeconomic selection indexes TERM 51 tandem (serial) selection DEFINITION 51 select for one trait until desired change is achieved (over yrs or generations) then select for another traitsimple strategycorrelation btwn diff traints is not being used to advantage, traits are unfavorable correlated progress achieved in one will be lost once selection begins for another TERM 52 independent culling levels DEFINITION 52 select for more than one trait simultaneouslymin standard set for each traitdone in same generationstandards must be set low enough that htere are sufficient numbers of replacementssuperiority in one trait not allowed to offset lower merit in another trait TERM 53 economic selection indexes DEFINITION 53 combine info on several traitsoptimizing profitdefine traits to improve (breeding objective)choose traits to measure (selection criteria)determine relationship btwn criteria and traits (heritabilities, correlations)decide economic importance of each trait in the breeding objective (economic weights)single index value (good and bad) TERM 54 pleiotropy DEFINITION 54 phenomenon of a single gene affecting more than one traitHYPPhalothane in swinepermanent TERM 55 linkage DEFINITION 55 temporaryoccurrence of two or more loci of interest on the same chromosomenot separated in crossing over if closegenerally passed to offspring togethercan concievably be separated TERM 56 genetic correlation DEFINITION 56 measure of strength of relationship btwn BV for one trait and BV for another traitmeasure relative importance of pleiotropic effects TERM 57 phenotypic correlation DEFINITION 57 measure performanceoften similar in size to genetic correlation TERM 58 environmental correlation DEFINITION 58 strength btwn environmental effectsgenerally much lower than other 2 TERM 59 correlated response DEFINITION 59 key equationused for traits difficult or expensive to measureunwanted or unforseen consequence if use direct