shahla Nematollahian; Masoud Alipanah
Abstract
Different types of imported and domesticatedhybrids of silkworm are rearing in different climatic conditions in Iran. The purpose of this study was to compare the performance of silkworm hybrids used in two climatic regions ofIran, namely Shaft in Guilan province and Torbat Heydariyeh in Khorasan Razavi ...
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Different types of imported and domesticatedhybrids of silkworm are rearing in different climatic conditions in Iran. The purpose of this study was to compare the performance of silkworm hybrids used in two climatic regions ofIran, namely Shaft in Guilan province and Torbat Heydariyeh in Khorasan Razavi province.For this study, four Iranian hybrids and 14 Chinese imported hybrids were used in a completely randomized block design. For the studied traitsnumber of cocoons per liter, average weight of a cocoon, and weight of cocoon produced from a box, there was a significant difference(P<0.01) between the hybrids as well as the regions. The results of the present study showed that the performance of silkworm hybrids, regardless of their origin, is more affected by the rearing environment and there is a difference between hybrids in the studied climates. Therefore, selecting the most suitable hybrids for different climates of Iran seem to be essential.
masoud alipanah
Abstract
In order to determine the interference of dominant effects on the estimation of genetic parameters, two models including additive and additive-dominance were used for estimation of genetic parameters of carcass traits in 631 hybrid beef bulls. Data analysis was conducted using Plink (V. 1.9) ...
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In order to determine the interference of dominant effects on the estimation of genetic parameters, two models including additive and additive-dominance were used for estimation of genetic parameters of carcass traits in 631 hybrid beef bulls. Data analysis was conducted using Plink (V. 1.9) and GVCBLUP (V. 3.9) softwares. Results of this study showed that most carcass quality traits have high heritability,but two traits namely hot carcass weight and ultrasound ribeye area had low heritability (0.15 and 0.11). Dominance variances have high contribution to the total variation of hot carcass weight, ultrasound ribeye area, ultrasound backfat thickness and ribeye area (0.13, 0.44, 0.89 and 0.33 respectively). However, dominant effect for other traits (lean meat yield, marbling score, backfat thickness, ultrasound ribeye area and grade of carcass) was not observed or was in very low amount. When dominance variance is low, its effect on GBLUP estimates is negligible. The estimates of heritability did not change significantly by the adding dominance effect into the model. The most important genomic regions that affect the carcass quality traits were belong to LAP3, THBS4 and PCDH9 genes. It is suggested that for the better understanding of the genetic structure of traits and better breeding plan, the dominance effects should be added into the model for geneticparameter estimation.