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1.
Reprod Domest Anim ; 47 Suppl 1: 2-6, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22212203

RESUMO

Bali cattle still represents 27% of the total cattle population in Indonesia, and it is considered the pillar breed for small farmers. Moreover, it is a breed of evolutionary importance regarding its direct ancestry from Banteng. However, there is a need for the establishment of a rational system for the evaluation of breeding soundness for indigenous Bali bulls to be used as sires for artificial insemination breeding programmes. Moreover, there is a need for cryobanking of well-identified genetic resources pertaining their use in evolutionary research and application as essential germplasm in breeding programmes.


Assuntos
Agricultura/economia , Bovinos/classificação , Conservação dos Recursos Naturais , Animais , Cruzamento , Criopreservação/veterinária , Feminino , Variação Genética , Indonésia , Masculino , Preservação do Sêmen/veterinária
2.
Reprod Domest Anim ; 47 Suppl 1: 15-7, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22212206

RESUMO

The present study reports the phenotypic variation of body weight and body size, the genetic variation of D-loop of mtDNA and microsatellite DNA allele in Aceh cattle in Indonesia within the frame of the design of a conservation programme for this indigenous species. Aceh cattle differ from Bali, Madura, Java-Ongole and Pesisir cattle, but its ancestry relates it closest to Pesisir, thus adding more information to its entry from the Indian sub-continent.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Repetições de Microssatélites/genética , Animais , Bovinos , Demografia , Feminino , Indonésia , Masculino , Filogenia
3.
J Anim Breed Genet ; 110(1-6): 41-56, 1993 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-21395702

RESUMO

SUMMARY: The stability of phenotypic, additive genetic and environmental variances of thorax length of Drosophila melanogaster in pure and synthetic strains was examined in two different environments. Two pure strains from different geographic locations (Melbourne and Townsville) were used, together with three synthetic populations formed from them. The existence of differences in thorax length between the Melbourne and Townsville populations, genotype by environment interaction, and heterosis in crosses between these populations indicate that they are genetically different. Thus geographic separation can cause differences in mean thorax length of flies from different populations. Both the difference in selection histories between the two localities and drift could lead to these differences. Up to the thirty fifth generation there was no evidence of any reduction in the difference between the Melbourne and Townsville populations, in either laboratory environment. The genetic differentiation of strains therefore may be maintained over many generations under new environmental conditions. The fluctuation over generations of heterosis of thorax length is possibly caused by the fluctuation of the rate of loss of favourable epistatic interaction in crossbred genotypes in combination with natural selection effects. V(p) was significantly higher in poor than in the good environment. This higher V(p) in the poor environment is most likly due to higher non additive genetic variance. V(p) was also significantly influenced by strain. In general, V(p) values of synthetic strains were higher than those of pure strains in both environments. Finally, the additive and environmental variances of thorax length were relatively stable across strains, generations and environments. ZUSAMMENFASSUNG: Wirkung von Herkünften, Kreuzungen und Umwelten auf additiv-genetische und phänotypische Varianzen in Drosophila melanogaster Die Stabilität phänotypischer, additiv-genetischer und umweltbedingter Varianzen der Thoraxlänge von Drosophila melanogaster in reinen und synthetischen Herkünften wurde in zwei verschiedenen Umwelten überprüft. Zwei reine Herkünfte von verschiedenen Gegenden (Melboune und Townsville) wurden zusammen mit drei zwischen ihnen gebildeten synthetischen Populationen untersucht. Unterschiede in Thoraxlänge zwischen Melbourne- und Townsvilleherkünften, Genotypumweltinteraktionen und Heterosis in Kreuzungen zwischen diesen Populationen zeigen, daß sie sich genetisch unterscheiden. Die geographische Trennung kann also Unterschiede in der mittleren Thoraxlänge zur Folge haben, wobei unterschiedliche Selektionsgeschichte in beiden Gegenden und Drift dies verursachen können. Bis zur 35. Generation gab es in keinem Labormilieu einen Hinweis auf eine Reduktion der Unterschiede zwischen den beiden Populationen. Die genetische Differenz der Herkünfte erhält sich daher auch unter neuen Umweltverhältnissen über viele Generationen. Die Schwankung in Heterosis für Thoraxlänge ist möglicherweise durch Schwankungen in der Verlustrate günstiger epistatischer Interaktionswirkungen in Kreuzungsgenotypen zusammen mit natürlichen Selektionswirkungen verursacht. V(p) war durch Umweltbedingungen signifikant beeinflußt und höher in schlechtem als in gutem Milieu. Der hohe Wert in schlechtem Milieu ist wahrscheinlich auf nicht-additiv-genetische Varianz zurückzuführen. V(p) wurde auch signifikant durch Herkunft beeinflußt und Werte in synthetischen Linien waren höher Linien in beiden Milieus. Additive und umweltbedingte Varianzen waren über Linie, Generationen und Umwelt relativ stabil.

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