الفهرس 
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Abstract
This study was carried out at Poultry Breeding Farm, Poultry Production Department, Faculty of Agriculture, Cairo University and National Gene Bank, Agricultural Research Center.
The aim of this study was to detect the genetic differences between two lines of Japanese Quail (Beige and Grey color) and also to determine the molecular description for these two lines by using means of molecular genetics under Egyptian conditions. The experiment was started on parent stock (male and female) of two quail lines and distributed in two batteries under the same environmental conditions, number of the bird analyzed. Fertilized eggs were collected during two weeks to be hatched. During the process of hatching, egg production has been recorded for four weeks. The feed and water were provided ad libitum. They were fed a diet containing 20 % crude protein and 2900 kcal ME/kg. All chicks (offspring) were reared under similar environmental, managerial and hygienic conditions. They were divided into two groups, first group (100 quails each line) housed in two batteries to calculated feed consumption and feed conversion ratio , the second group were brooded in electrical brooding batteries up to two weeks of age. At the end of the second week of age, housed on floor to marketing (6 weeks of age).The feed and water were provided ad libitum. To estimate variability between quail lines, six microsatellite markers were used. The markers constructed for 6 autosomal 1, 3, 4, 6, CJA 06 and QL08 chromosomes.
Main results could be summarized as follows:
1. The significantly (P>0.05) of higher mean egg production was recorded to Grey line quail compared to Beige one.
2. Percentage of fertility, hatchability based on fertile egg and hatchability based on total eggs set were higher in Grey line compared to Beige line.
3. Percentages of addled and infertile eggs were higher in Beige line compared to Grey line.
4. The results showed that body weight of Grey line was significantly higher than that of Beige line at 3, 4, 5 and 6 weeks.
5. The results showed significantly higher body weight gain in Grey line compared to Beige line except 3-4 weeks of age.
6. Feed intake was significantly higher in Beige compared to Grey line at 1, 2, 3, 5, 6 and 1-6 weeks of age.
7. The improvement was observed for feed conversion ratio in Grey line compared to Beige line at 3, 5 and 1-6 weeks of age. No significant differences were observed between the two lines in all periods handled in this study except at 3, 5 and 1-6 weeks of age.
8. There were a significant differences in live body and Blood weight between Grey and Beige quail lines. However, non-significant differences occurred for Feather, legs, head and inedible meat parts weight between quail lines.
9. There was a significant difference in carcass, liver, giblets and Edible meat parts weight between Grey and Beige quail lines. However, non-significant differences occurred for gizzard and heart weight between quail lines.
10. The differences between lines were not significant at (P≤0.05) for total protein, albumin and globulin. Albumin / globulin ratio was significantly higher in Grey line compared to Beige line. Cholesterol and total lipids Concentrations were significantly higher in Beige line than Grey line.
11. The percentage of mortality rate was higher in Grey line compared to Beige line.
12. Genetic diversity of Beige and Grey lines showed that the mean number of alleles per line varied from 6.00 in Beige to 6.50 in Grey lines. Total number of alleles were54 based on six microsatellite loci. The number of alleles per locus overall lines ranged from 5 (UBC005) to14 (UBC001) with a mean of 9.00.The genetic diversity within the two lines (Beige and Grey) analyzed were described by the number of alleles per locus.
13. The estimates of observed (Ho) and expected (He) heterozygosity were obtained using the allele frequency data for each locus in each line. The observed heterozygosity values across loci showed large variation ranged between 0.00 for loci GUJ0029, UBC001, UBC002 and UBC004 to 0.40 for loci GUJ0028 and UBC005 with an overall mean of 0.13 for Beige line. Also, the observed heterozygosity values showed large variation ranged between 0.00 for loci UBC001, UBC002 and UBC004 to 0.22 for locus UBC005 with an overall mean of 0.09 for Grey line. Furthermore, the expected heterozygosity across loci showed large differences that ranged between 0.38 for locus UBC005 and 0.86 for locus UBC001, with an overall mean of 0.0.66 for Beige line and 0.11 for locus GUJ0028 to 0.82 for locus UBC001 with the mean 0.0.49 for Grey respectively. Only GUJ0029 and UBC001 loci for Beige and GUJ0028, UBC004 and UBC005 loci for Grey had an expected heterozygosity less than 0.50.
14. These results showed that, the genetic diversity was highest in Beige line as compared to Grey line and reflected the efficiency of used set of microsatellite markers set in studying the genetic variation within and between closely related Japanese quail lines.
15. The mean values of FIS obtained were 0.82 and 0.80 for Beige and Grey lines, respectively, indicating the high level of inbreeding in lines studied confirming by IC which equal to 0.80 and 0.82, respectively.
16. The mean values of FIS, FIT and FST obtained were 0.80, 0.82 and 0.12 per locus, respectively. Wright’s fixation index (Fis) values among loci ranged from -0.158 (for UBC0005) to 1.000 (for UBC0001, UBC0002 and UBC0004). The mean Fis for 6 microsatellite loci was 0.800. The Fis were 0.82 and 0.80 for Beige and Grey lines, respectively. The F-statistics (Fis, Fst, and Fit) for each locus.
17. The majority of the genetic diversity obtained in the current study is presented by within individuals (15.24%) rather than others. Fixation indices give an idea about the population structure in terms of inbreeding coefficient and population differentiation. Population fixation indices traced a 0.848 of variation referring to differences among individuals versus total variance (FIT).
18. Percent of molecular variance among lines varied from 2% with the UBC0005 locus to 25% with the GUJ0028 while, the Percent of molecular variance within lines varied from 75% with the GUJ0028 locus to 98% with the UBC0005 locus these results revealed that, the variance within lines higher than among lines per locus.
19. The highest allele frequency overall loci was 0.68 of allele 060bp at locus UBC0005 in the case of Grey population. Whereas, the lowest one was 0.02 associated with Grey and Beige lines at two loci GUJ0028 (for alleles, 099, 108 and 126bp) and GUJ0029 for allele 116bp with Beige line. The highest average of allele frequency estimated was for Beige line at locus UBC005 (0.33). On the other hand, the lowest one was 0.10 in the case of locus UBC001 for Beige line.
20. The average PIC of six markers was 0.66 and 0.71 with Beige and Grey line, respectively which indicated that the six microsatellite markers contained highly polymorphic loci in both lines of Japanese Quail.
It could be concluded that the phenotypic characters of Grey quail line was better than Beige line in general, genetic differences between Grey and Beige Quail lines were low, the high polymorphism of microsatellite loci suggested that these markers could be utilized in future to assess genetic diversity of Japanese quail lines, the markers GUJ0028, GUJ0029, UBC001 and UBC002 could be attributed as marker assisted selection (MAS) to improve the performance of Japanese quail.