Author(s) |
Bunter, K L
Hermesch, S
Luxford, B G
Graser, H -U
Crump, R E
|
Publication Date |
2005-09
|
Abstract |
Insulin-like growth factor-I (IGF-I) is a naturally occurring polypeptide produced in the liver, muscle and fat tissues. It is known to be associated with growth and development during the post-natal growth period. Evidence for strong genetic correlations between juvenile IGF-I and performance traits would suggest this physiological measure would be useful as an early selection criterion. This paper reports estimates of genetic parameters from 9 trials where IGF-I was measured in juvenile pigs. All trials involved populations undergoing active selection for improved performance (e.g. efficient lean meat growth). Juvenile IGF-I was moderately heritable (average h2: 0.31) and influenced by common litter effects (average c2: 0.15). Genetic correlations (rg) between juvenile IGF-I and backfat (BF), feed intake (FI) or feed conversion ratio (FCR) traits were generally large and positive: rg averaged 0.57, 0.41 and 0.65, respectively. Phenotypic correlations (rp) between juvenile IGF-I and BF, FI or FCR were much lower (rp averaged 0.21, 0.09, and 0.15, respectively) as residual correlations between IGF-I and these performance traits were low, consistent with being measured at very different times. Correlations (genetic or phenotypic) between juvenile IGF-I and growth traits (e.g. lifetime daily gain or test daily gain) were relatively low, with average values within ± 0.09 of zero. Results from the trials reported here, and several physiological studies, indicate that information on juvenile IGF-I concentration can be used as an early physiological indicator of performance traits traditionally measured later in life. There is a clear role for juvenile IGF-I to facilitate pre-selection and more accurate selection of livestock for hard to measure traits, such as FCR, in pig breeding programmes.
|
Citation |
Proceedings of the Association for the Advancement of Animal Breeding and Genetics, v.16, p. 90-90
|
ISBN |
0643092331
064309234X
|
ISSN |
1328-3227
|
Link | |
Title |
Insulin-like Growth Factor-I Measured (IGF-I) in Juvenile Pigs is Genetically Correlated with Economically Important Performance Traits
|
Type of document |
Conference Publication
|
Entity Type |
Publication
|
Name | Size | format | Description | Link |
---|