Open Access. Powered by Scholars. Published by Universities.®

Life Sciences Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Life Sciences

Heritable And Experiential Effects On Boldness In A Tropical Poeciliid, Culum Brown, Fiona Burgess, Victoria Braithwaite Dec 2007

Heritable And Experiential Effects On Boldness In A Tropical Poeciliid, Culum Brown, Fiona Burgess, Victoria Braithwaite

Sentience Collection

Consistent differences in human behaviour are often explained with reference to personality traits. Recent evidence suggests that similar traits are widespread across the entire animal kingdom and that they may have substantial fitness consequences. One of the major components of personality is the shyness–boldness continuum. Little is known about the relative contributions of genes and the environment in the development of boldness in wild animal populations. Here, we bred wild-caught fish (Brachyraphis episcopi) collected from regions of highand low-predation pressure, reared their offspring in the laboratory under varying conditions and tested boldness utilising an open-field paradigm. First-generation laboratory-reared fish showed …


The Influence Of Early Experience On, And Inheritance Of, Cerebral Lateralization, Culum Brown, Jac Western, Victoria A. Braithwaite Aug 2007

The Influence Of Early Experience On, And Inheritance Of, Cerebral Lateralization, Culum Brown, Jac Western, Victoria A. Braithwaite

Veterinary Science and Medicine Collection

Cerebral lateralization refers to the lateralized partitioning of cognitive function in either hemisphere of the brain. Using a standard detour test, we investigated lateralized behaviour in wild-caught, female poeciliid fish, Brachyraphis (=Brachyrhaphis) episcopi, from high- and low-predation areas. Wild fish were bred and their offspring reared under controlled laboratory conditions. These laboratory-reared fish were screened in the same laterality assays as their parents. We observed differences between wild-caught females and their laboratory-reared female offspring in the pattern of lateralization (tendency to use one hemisphere over the other to process information). Conversely, the strength of lateralization (consistency of hemispherical bias) was …


A General Review Of Competition Genetic Effects With An Emphasis On Swine Breeding, C. Y. Chen, Rodger K. Morota, S. Newman, L. D. Van Vleck Jan 2007

A General Review Of Competition Genetic Effects With An Emphasis On Swine Breeding, C. Y. Chen, Rodger K. Morota, S. Newman, L. D. Van Vleck

Department of Animal Science: Faculty Publications

A review of previous studies is presented on estimates of genetic parameters and responses to selection with traditional breeding approaches, on correlations between agonistic behavior and growth performance, and on theoretical frameworks for selection incorporating interactions among individuals and on practical methods for incorporating competition effects in breeding programs.


Estimates Of Genetic Parameters For Racing Times Of Thoroughbred Horses, Bülent Eki̇z, Ömür Koçak Jan 2007

Estimates Of Genetic Parameters For Racing Times Of Thoroughbred Horses, Bülent Eki̇z, Ömür Koçak

Turkish Journal of Veterinary & Animal Sciences

The aim of this study was to estimate the genetic parameters for racing times, which are needed for a selection program of Thoroughbred horses in Turkey. The racing records used in the study were obtained from the Turkish Jockey Club. The trait used in the study was racing time for racing distances of 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, and 2400 m. The data from each racing distance were analyzed separately. Genetic parameters were estimated by REML procedure using the DFREML program. Estimates of heritability ranged from 0.177 to 0.353, depending on the racing distance. …


Environmental And Genetic Effects On Birth Weight And Survival Rate In Holstein Calves, Serdar Koçak, Mustafa Tekerli̇, Ceyhan Özbeyaz, Banu Yüceer Jan 2007

Environmental And Genetic Effects On Birth Weight And Survival Rate In Holstein Calves, Serdar Koçak, Mustafa Tekerli̇, Ceyhan Özbeyaz, Banu Yüceer

Turkish Journal of Veterinary & Animal Sciences

This study was undertaken to investigate the effects of certain factors on birth weight and survival rate, utilizing the records of 8399 Holstein calves maintained at the Ceylanpınar State Farm in southeastern Anatolia. The data were collected from the calf barn sheets, including birth weight, pedigree details, and calf fate. The survival rate was scored as 1 (alive) or 0 (died) in accordance with the records. Analysis of variance indicated that the effects of year, season, parity, and calf sex on birth weight were significant (P < 0.01). Only calf sex had a significant (P < 0.01) influence on survival rate. The least squares means of birth weight for all calves averaged 38.79 ± 0.171 kg. The survival rates were 0.95 ± 0.004, 0.94 ± 0.004, and 0.92 ± 0.005 at 3, 6, and 12 months of life, respectively. Heritabilities were 0.115 ± 0.0023 for birth weight and 0.020 ± 0.009, 0.011 ± 0.008, and 0.011 ± 0.008 for 3-month, 6-month, and 12-month survival rates. Genetic correlations between birth weight and every rate of survival were estimated as -0.113, -0.012, and 0.106. The corresponding phenotypic correlations were 0.022, 0.014, and -0.013. It was concluded that the birth weight and survival rates of Holstein calves reared at Ceylanpınar State Farm were acceptable. However, further improvements can be accomplished by more effective feeding and management based on the low heritabilities.