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Author Graham, M.; Letz, R.
Title Within-species variation in the development of ultrasonic signaling of preweanling rats Type Journal Article
Year 1979 Publication Developmental Psychobiology Abbreviated Journal Dev Psychobiol
Volume 12 Issue 2 Pages 129-136
Keywords Animals; *Animals, Newborn; Animals, Suckling; Body Weight; Cold/adverse effects; Environment; Genotype; Individuality; Object Attachment; Rats; Stress/*physiopathology; Ultrasonics; *Vocalization, Animal
Abstract The development of litter and individual differences in the rate of ultrasonic signaling of neonatal rats was studied. Systematic variations among litters and individuals emerged, without differential treatment. These differences were not correlated with variations in general development as indexed by body weight. Two experiments using a cross-fostering design showed that litter differences developed independently of variations in postnatal environment. These results indicate that the variations among litters in ultrasound rate have a prenatal, possibly genetic, etiology and may represent reliable indicants of response to environmental stress.
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Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-1630 ISBN Medium
Area Expedition Conference
Notes PMID:456751 Approved no
Call Number Equine Behaviour @ team @ Serial 4172
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Author Kristjansson, T.; Bjornsdottir, S.; Sigurdsson, A.; Andersson, L.S.; Lindgren, G.; Helyar, S.J.; Klonowski, A.M.; Arnason, T.
Title The effect of the ‘Gait keeper’ mutation in the DMRT3 gene on gaiting ability in Icelandic horses Type Journal Article
Year 2014 Publication Journal of Animal Breeding and Genetics Abbreviated Journal J. Anim. Breed. Genet.
Volume Issue Pages n/a-n/a
Keywords Gaiting ability; genotype effect; genotype probability
Abstract A nonsense mutation in DMRT3 (‘Gait keeper’ mutation) has a predominant effect on gaiting ability in horses, being permissive for the ability to perform lateral gaits and having a favourable effect on speed capacity in trot. The DMRT3 mutant allele (A) has been found in high frequency in gaited breeds and breeds bred for harness racing, while other horse breeds were homozygous for the wild-type allele (C). The aim of this study was to evaluate further the effect of the DMRT3 nonsense mutation on the gait quality and speed capacity in the multigaited Icelandic horse and demonstrate how the frequencies of the A- and C- alleles have changed in the Icelandic horse population in recent decades. It was confirmed that homozygosity for the DMRT3 nonsense mutation relates to the ability to pace. It further had a favourable effect on scores in breeding field tests for the lateral gait tölt, demonstrated by better beat quality, speed capacity and suppleness. Horses with the CA genotype had on the other hand significantly higher scores for walk, trot, canter and gallop, and they performed better beat and suspension in trot and gallop. These results indicate that the AA genotype reinforces the coordination of ipsilateral legs, with the subsequent negative effect on the synchronized movement of diagonal legs compared with the CA genotype. The frequency of the A-allele has increased in recent decades with a corresponding decrease in the frequency of the C-allele. The estimated frequency of the A-allele in the Icelandic horse population in 2012 was 0.94. Selective breeding for lateral gaits in the Icelandic horse population has apparently altered the frequency of DMRT3 genotypes with a predicted loss of the C-allele in relatively few years. The results have practical implications for breeding and training of Icelandic horses and other gaited horse breeds.
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Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1439-0388 ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number Equine Behaviour @ team @ Serial 5831
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Author Ricard, A.; Chanu, I.
Title Genetic parameters of eventing horse competition in France Type Journal Article
Year 2001 Publication Genetics, Selection, Evolution. : GSE Abbreviated Journal Genet Sel Evol
Volume 33 Issue 2 Pages 175-190
Keywords Animals; Behavior, Animal; Female; France; Genotype; Horses/*genetics; Male; Physical Conditioning, Animal; Selection (Genetics); *Sports; Stereotyped Behavior
Abstract Genetic parameters of eventing horse competitions were estimated. About 13 000 horses, 30 000 annual results during 17 years and 110 000 starts in eventing competitions during 8 years were recorded. The measures of performance were logarithmic transformations of annual earnings, annual earnings per start, and annual earnings per place, and underlying variables responsible for ranks in each competition. Heritabilities were low (0.11 / 0.17 for annual results, 0.07 for ranks). Genetic correlations between criteria were high (greater than 0.90) except between ranks and earnings per place (0.58) or per start (0.67). Genetic correlations between ages (from 5 to 10 years old) were also high (more than 0.85) and allow selection on early performances. The genetic correlation between the results in different levels of competition (high/international and low/amateur) was near 1. Genetic correlations of eventing with other disciplines, which included partial aptitude needed for eventing, were very low for steeplechase races (0.18) and moderate with sport: jumping (0.45), dressage (0.58). The results suggest that selection on jumping performance will lead to some positive correlated response for eventing performance, but much more response could be obtained if a specific breeding objective and selection criteria were developed for eventing.
Address Institut national de la recherche agronomique, Station de genetique quantitative et appliquee, 78352 Jouy-en-Josas Cedex, France. ugenata@dga.inra.fr
Corporate Author Thesis
Publisher Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0999-193X ISBN Medium
Area Expedition Conference
Notes PMID:11333833 Approved no
Call Number Equine Behaviour @ team @ Serial 3728
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