Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning
<p>Abstract</p> <p>Records for birth and subsequent, monthly weights until weaning on beef calves of two breeds in a selection experiment were analysed fitting random regression models. Independent variables were orthogonal (Legendre) polynomials of age at weighing in days. Orders...
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| Format: | Article |
| Language: | deu |
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BMC
2001-09-01
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| Series: | Genetics Selection Evolution |
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| Online Access: | http://www.gsejournal.org/content/33/5/487 |
| _version_ | 1818787666747981824 |
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| author | Meyer Karin |
| author_facet | Meyer Karin |
| author_sort | Meyer Karin |
| collection | DOAJ |
| description | <p>Abstract</p> <p>Records for birth and subsequent, monthly weights until weaning on beef calves of two breeds in a selection experiment were analysed fitting random regression models. Independent variables were orthogonal (Legendre) polynomials of age at weighing in days. Orders of polynomial fit up to 6 were considered. Analyses were carried out fitting sets of random regression coefficients due to animals' direct and maternal, additive genetic and permanent environmental effects, with changes in variances due to temporary environmental effects modelled through a variance function, estimating up to 67 parameters. Results identified similar patterns of variation for both breeds, with maternal effects considerably more important in purebred Polled Herefords than a four-breed synthetic, the so-called Wokalups. Conversely, repeatabilities were higher for the latter. For both breeds, heritabilities decreased after birth, being lowest when maternal effects were most important around 100 days of age. Estimates at birth and weaning were consistent with previous, univariate results.</p> |
| first_indexed | 2024-12-18T14:11:24Z |
| format | Article |
| id | doaj.art-7f18f9db24df485eb9fba9bc55fbb339 |
| institution | Directory Open Access Journal |
| issn | 0999-193X 1297-9686 |
| language | deu |
| last_indexed | 2024-12-18T14:11:24Z |
| publishDate | 2001-09-01 |
| publisher | BMC |
| record_format | Article |
| series | Genetics Selection Evolution |
| spelling | doaj.art-7f18f9db24df485eb9fba9bc55fbb3392022-12-21T21:05:07ZdeuBMCGenetics Selection Evolution0999-193X1297-96862001-09-0133548751410.1186/1297-9686-33-5-487Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaningMeyer Karin<p>Abstract</p> <p>Records for birth and subsequent, monthly weights until weaning on beef calves of two breeds in a selection experiment were analysed fitting random regression models. Independent variables were orthogonal (Legendre) polynomials of age at weighing in days. Orders of polynomial fit up to 6 were considered. Analyses were carried out fitting sets of random regression coefficients due to animals' direct and maternal, additive genetic and permanent environmental effects, with changes in variances due to temporary environmental effects modelled through a variance function, estimating up to 67 parameters. Results identified similar patterns of variation for both breeds, with maternal effects considerably more important in purebred Polled Herefords than a four-breed synthetic, the so-called Wokalups. Conversely, repeatabilities were higher for the latter. For both breeds, heritabilities decreased after birth, being lowest when maternal effects were most important around 100 days of age. Estimates at birth and weaning were consistent with previous, univariate results.</p>http://www.gsejournal.org/content/33/5/487covariance functionsearly growthmodellingbeef cattlematernal effects |
| spellingShingle | Meyer Karin Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning Genetics Selection Evolution covariance functions early growth modelling beef cattle maternal effects |
| title | Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning |
| title_full | Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning |
| title_fullStr | Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning |
| title_full_unstemmed | Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning |
| title_short | Estimates of direct and maternal covariance functions for growth of Australian beef calves from birth to weaning |
| title_sort | estimates of direct and maternal covariance functions for growth of australian beef calves from birth to weaning |
| topic | covariance functions early growth modelling beef cattle maternal effects |
| url | http://www.gsejournal.org/content/33/5/487 |
| work_keys_str_mv | AT meyerkarin estimatesofdirectandmaternalcovariancefunctionsforgrowthofaustralianbeefcalvesfrombirthtoweaning |