Genotypic characterization of microsatellite markers in broiler and layer selected chicken lines and their reciprocal F1s

Abstract

Chicken experimental populations have been developed worldwide for QTL mapping, but their genotypic characterizations are not usually discussed. The objective of this study was to characterize genotypically two F 1 reciprocal generations and their parental lines based on the estimation of genotypic parameters. These F 1 generations originated two Brazilian reference populations to map QTL. The evaluated parameters were polymorphic information content (PIC), observed and expected heterozygosities and number of alleles at microsatellite loci on chromosomes 1, 3 and 4. All parental and F 1 chickens from both populations were used totalling of 83 chickens: 14 from a broiler (TT) and 14 from a layer line (CC) and 55 from their reciprocal F 1 generations. The chicken lines and the resource populations were developed at the National Research Center for Swine and Poultry (EMBRAPA), Brazil. Genotypes from all animals were obtained from 34 loci on chromosomes 1 (13), 3 (12) and 4 (9). Based on the sampling, we found that the two lines exhibited a total of 163 different alleles, of which 31 (31.1%) and 44 (33.0%) alleles were unique in CC and TT lines, respectively, with allelic frequencies ranging from 0.03 to 0.82. The observed heterozygosity was higher (0.68-0.71) in both F 1 generations than in their founder lines due to linkage disequilibrium. Finally, the two chicken lines used as founders created two F 1 reciprocal generations with high levels of PIC (0.50-0.52) and observed heterozygosity, as well as satisfactory number of alleles per locus (4.06-4.32). Our results will allow to compare and select families with highly informative microsatellite markers for QTL studies, reducing genotyping costs.

Genotypic characterization of ten microsatellite loci in two Brazilian free range (Caipira) chicken lines

“…CLEMENTINO et al (2010) andFONTEQUE et al (2014) found an average number of 9.6 and 12.4 alleles per locus, respectively, in studies with microsatellites in free range chickens from Brazil. Lower values than the results found in this study were also described by AL-QAMASHOUI et al (2014) - 8.4 (VANHALA et al, 1998;KYSER et al, 2000;ZHANG et al, 2002;HILLEL et al, 2003;TADANO et al, 2007;BERTHOULY et al, 2008;ROSÁRIO et al, 2009;CHATTERJEE et al, 2010;TADANO et al, 2012;WILKINSON et al, 2012). Normally, it is expected that the genetic variability of commercial chickens lines had been reduced because they are selected for quantitative traits (HILLEL et al, 2003).…”

“…The Ho values are higher as some commercial populations (ROSÁRIO et al, 2009;CHATTERJEE et al, 2010;TADANO et al, 2012). However, in the commercial chickens the Ho values were often lower than that in the present study.…”

Identification and characterization of microRNAs expressed in chicken skeletal muscle

“…The TT line was selected for body weight, feed conversion, carcass yield, viability, fertility, hatchability, and reduced abdominal fat. The CC line was selected for egg production, egg weight, feed conversion, hatchability, sexual maturity, fertility, viability, egg quality, and reduced body weight (Rosario et al, 2009).…”

Precision of distances and ordering of microsatellite markers in consensus linkage maps of chromosomes 1, 3 and 4 from two reciprocal chicken populations using bootstrap sampling

“…Thus, about 4200 F 2 offspring were obtained from both populations. Details are in Rosário et al (2009).…”

“…DNA extraction, polymerase chain reactions (PCR) and genotyping steps were run as in Rosário et al (2009). A total of 31 (13), 12 (12) and 7 (9) microsatellite markers were used in TCTC (CTCT) populations on GGA1, GGA3 and GGA4, respectively.…”