Genomics Can Contribute to Selection to Improve Bottle Teats in Tropical Beef Genotypes

Title
Genomics Can Contribute to Selection to Improve Bottle Teats in Tropical Beef Genotypes
Publication Date
2017
Author(s)
Wolcott, Matthew L
( author )
OrcID: https://orcid.org/0000-0001-6786-8742
Email: mwolcott@une.edu.au
UNE Id une-id:mwolcott
Johnston, David
( author )
OrcID: https://orcid.org/0000-0002-4995-8311
Email: djohnsto@une.edu.au
UNE Id une-id:djohnsto
Zhang, Yuandan
( author )
OrcID: https://orcid.org/0000-0002-1998-3313
Email: yzhang4@une.edu.au
UNE Id une-id:yzhang4
Editor
Editor(s): Laercio Porto-Neto
Type of document
Conference Publication
Language
en
Entity Type
Publication
Publisher
Association for the Advancement of Animal Breeding and Genetics (AAABG)
Place of publication
Armidale, Australia
UNE publication id
une:23614
Abstract
Beef CRC research showed that a subjective score of teat size (small (1) to large (5)) was heritable in tropically adapted Brahman (BRAH) and Tropical Composite (TCOMP) cows, and that higher teat scores (bottle teats) were genetically associated with higher calf losses from birth to weaning. Teat traits are only expressed in females, and the research showed that they tended to display more variation in later life; making them ideal candidates for genomic selection. Front and rear teat scores (TSF and TSB respectively) were recorded in cows at calving through up to 6 matings. From these, a trait was created which described a cows maximum lifetime teat score (TSM), as well as a binary trait which distinguished cows that received a teat score of 4 or 5 at any time through their lives (1) from those which did not (0) (MSB). Results confirmed the heritability of TSF and TSB (h² = 0.30 to 0.40), and variation in both TSM and MSB was also shown to have a genetic basis (h² = 0.49 and 0.46 respectively for BRAH, and 0.29 and 0.22 for TCOMP). Genome wide association analyses identified large numbers of significant SNPs but did not suggest a likelihood of identifying a small number of SNPs of large effect. It is unlikely therefore, that a simple diagnostic test (based a small number of SNPs) could be developed for the traits. Conventional genomic selection, however, is likely to present opportunities to improving teat traits by selection in tropically adapted beef genotypes, with accuracies of genomic prediction of 0.23 to 0.35 for TSM and MSB across both genotypes.
Link
Citation
Proceedings of the Association for the Advancement of Animal Breeding and Genetics, v.22, p. 171-174
ISSN
1328-3227
Start page
171
End page
174

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