נגישות
menu      
Advanced Search
Syntax
Search...
Volcani treasures
About
Terms of use
Manage
Community:
אסיף מאגר המחקר החקלאי
Powered by ClearMash Solutions Ltd -
Segregation among test-cross progeny suggests that two complementary dominant genes explain the difference between ascites-resistant and ascites-susceptible broiler lines
Year:
2007
Source of publication :
Poultry Science
Authors :
Druyan, Shelly
;
.
Volume :
86
Co-Authors:
Druyan, S., Hebrew University, Faculty of Agricultural, Food and Environmental Quality Sciences, PO Box 12, Rehovot 76100, Israel
Cahaner, A., Hebrew University, Faculty of Agricultural, Food and Environmental Quality Sciences, PO Box 12, Rehovot 76100, Israel
Facilitators :
From page:
2295
To page:
2300
(
Total pages:
6
)
Abstract:
Ascites syndrome (AS) is a major cause of economic losses to the broiler industry. The tendency of broilers to develop AS was found to be heritable, suggesting that selective breeding could provide a solution to this problem. To further elucidate the genetic control of AS, AS-susceptible (AS-S) and AS-resistant (AS-R) lines were established by 3 cycles of divergent selection on pedigree data of AS mortality under AS-inducing conditions. The rapid divergence between the lines suggested the involvement of a major gene with dominance for AS resistance. It was hypothesized that the difference between the lines is controlled by a single dominant gene, denoted A, with AA (and some Aa) individuals in the ASR line, and aa individuals in the AS-S line. The current study was designed to test this hypothesis by test-crossing heterozygous (Aa) sires from the AS-R line and F1 from the AS-R x AS-S cross, with recessive homozygous (aa) dams from the AS-S line. A ratio of 1:1 was expected between progeny with AS vs. healthy progeny when reared under AS-inducing conditions. Test-cross progeny of 5 sires from the AS-R line segregated 1:1, indicating that these sires were heterozygous (Aa) in the suggested major gene and thus supporting the hypothesis of a single major gene with dominance of AS resistance. There was segregation among test-cross progeny of 8 F1 sires, but with a 3:1 ratio of AS progeny to healthy progeny. The 3:1 ratio is expected if the F1 sires are heterozygous (AaBb) with complementary interaction between the dominant alleles in 2 unlinked major genes. The segregation among test-cross progeny of the 9 heterozygous AS-R sires could also be explained by the same model. These results suggested that 2 major genes are responsible for the difference between the AS-R and AS-S lines. Resource populations derived from these lines will facilitate an efficient genomic search for these 2 genes. Once the alleles of these genes are identified and genotyping tests are developed, breeders will easily be able to select against AS susceptibility. ©2007 Poultry Science Association Inc.
Note:
Related Files :
Animal
animal disease
Animals
Chickens
Female
Genetics
Male
Poultry Diseases
Test cross
Show More
Related Content
More details
DOI :
10.3382/ps.2007-00018
Article number:
Affiliations:
Database:
Scopus
Publication Type:
article
;
.
Language:
English
Editors' remarks:
ID:
21315
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:43
You may also be interested in
Scientific Publication
Segregation among test-cross progeny suggests that two complementary dominant genes explain the difference between ascites-resistant and ascites-susceptible broiler lines
86
Druyan, S., Hebrew University, Faculty of Agricultural, Food and Environmental Quality Sciences, PO Box 12, Rehovot 76100, Israel
Cahaner, A., Hebrew University, Faculty of Agricultural, Food and Environmental Quality Sciences, PO Box 12, Rehovot 76100, Israel
Segregation among test-cross progeny suggests that two complementary dominant genes explain the difference between ascites-resistant and ascites-susceptible broiler lines
Ascites syndrome (AS) is a major cause of economic losses to the broiler industry. The tendency of broilers to develop AS was found to be heritable, suggesting that selective breeding could provide a solution to this problem. To further elucidate the genetic control of AS, AS-susceptible (AS-S) and AS-resistant (AS-R) lines were established by 3 cycles of divergent selection on pedigree data of AS mortality under AS-inducing conditions. The rapid divergence between the lines suggested the involvement of a major gene with dominance for AS resistance. It was hypothesized that the difference between the lines is controlled by a single dominant gene, denoted A, with AA (and some Aa) individuals in the ASR line, and aa individuals in the AS-S line. The current study was designed to test this hypothesis by test-crossing heterozygous (Aa) sires from the AS-R line and F1 from the AS-R x AS-S cross, with recessive homozygous (aa) dams from the AS-S line. A ratio of 1:1 was expected between progeny with AS vs. healthy progeny when reared under AS-inducing conditions. Test-cross progeny of 5 sires from the AS-R line segregated 1:1, indicating that these sires were heterozygous (Aa) in the suggested major gene and thus supporting the hypothesis of a single major gene with dominance of AS resistance. There was segregation among test-cross progeny of 8 F1 sires, but with a 3:1 ratio of AS progeny to healthy progeny. The 3:1 ratio is expected if the F1 sires are heterozygous (AaBb) with complementary interaction between the dominant alleles in 2 unlinked major genes. The segregation among test-cross progeny of the 9 heterozygous AS-R sires could also be explained by the same model. These results suggested that 2 major genes are responsible for the difference between the AS-R and AS-S lines. Resource populations derived from these lines will facilitate an efficient genomic search for these 2 genes. Once the alleles of these genes are identified and genotyping tests are developed, breeders will easily be able to select against AS susceptibility. ©2007 Poultry Science Association Inc.
Scientific Publication
You may also be interested in