• Asian-Australasian Journal of Animal Sciences
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• v.17 no.5
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• pp.598-602
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• 2004

The Tongcheng pig breed is a famous Chinese indigenous breed. The Ministry of Agriculture of China has filed it as 1 of 19 national key conservation breeds selected from more than 100 Chinese indigenous pig breeds in 2000. In order to improve the reproductive performance, it has been intensively selected to increase the litter size for about 10 years. The population randomly sampled from conservation nucleus of eight families in the Tongcheng pigs was genotyped for identification of their estrogen receptor locus polymorphisms with the PCR-RFLPs method. Only AB heterozygotes and BB homozygotes were detected, and $X^2$ test demonstrated that the locus was in disequilibrium at a significant level (p<0.05). In the present paper, the litter sizes in different parities were regarded as different traits. Holistic status of other unspecific and unidentified genes was estimated by using the statistical methods. Coefficients of kurtosis and skewness showed that the litter size still presented segregating characteristic in the 2nd, 5th, 7th, 8th and 9th parities. Analysis of homogeneity of variance between families confirmed the results for the 5th, 7th and 8th parities. The heritability of litter size for the 1st to 10th parities was estimated with paternal half-sib model and individual estimated breeding values (EBVs) were evaluated by a single trait animal model as well. We found that the averages of EBVs for litter size in each parity did not differ significantly between genotypes, despite the significant difference for original phenotype records in the 3rd, 4th and 5th parities (p<0.05 or p<0.01). The results may be explained by the deduction that the polymorphisms of ESR locus are no longer the important genetic base of litter size variation when the frequency of allele B accumulated in the experience of selection procedure, and further conferring that there exist special genes associated with litter size in the recent Tongcheng pigs population can be made.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.325-325
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• 2022

In order to developing high-quality rice varieties and processing varieties, systematic and stable evaluation of physicochemical properties is required for breeding lines. In this study, we compared the quality characteristics evaluation results of rice breeding lines for cooked rice, special rice, and whole crop silage rice adapted to central plain region (Suwon) in order to use as basic data for future rice variety development. Brown rice length/width ratio, head rice ratio, protein content, amylose content, alkali digestion value(ADV) and Toyo value were analyzed to evaluate the quality characteristics of yield trial lines cultivated in Suwon for four years (2017-2020). Brown rice length/width ratio, head rice ratio, protein content, ADV and Toyo values showed significant differences by year, but there was no significant difference in amylose content (p<0.05), which showed little environmental variation. The head rice ratio and Toyo value showed an increasing trend, while the protein content showed a decreasing trend. However, the protein content was the highest in 2020, which is thought to be owing to little sunlight hours due to heavy rainfall in 2020. The protein content of whole crop silage rice was 8.1%, which was significantly higher than that of other lines (p<0.05). Toyo value of medium-maturing and early-maturing lines were 67.6 and 73.7%, respectively, and the Toyo value of medium-maturing lines was higher than that of the early-maturing lines (p<0.05). In correlation analysis among the quality characteristics of the rice lines for cooked rice, significant positive correlations were detected between Toyo value and head rice ratio, amylose content, ADV, and a negative correlation was observed between Toyo value and protein content (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.1
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• pp.69-78
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• 2015

A non-traditional forage-based protocol was employed to evaluate replacement heifer growth, fertility, and economics between small frame (SF, 3.50; n = 50) and large frame (LF, 5.56; n = 50) heifers using three increasing gain growth phases. Preceding an 85 d growing-breeding period (Phase 3; P3) the heifers were managed as a common group for Phases 1 and 2 (P1 and P2). During P1, heifers grazed common fields of unharvested corn and corn residue (total digestible nutrients [TDN] 56%) with supplemental hay. For P2, heifers grazed early spring crested wheatgrass pasture (CWG; TDN 62%) that was followed by the final P3 drylot growing and breeding period (TDN 68%). Small frame heifers were lighter at the end of P1 in May and at the start of P3 breeding in August (p = 0.0002). Percent of mature body weight (BW) at the end of P1 (209 d) was 48.7% and 46.8%, respectively, for the SF and LF heifers and the percent pubertal was lower for SF than for LF heifers (18.0% vs 40.0%; p = 0.02). At breeding initiation (P3), the percentage of mature BW was 57.8 and 57.2 and the percentage pubertal was 90.0 and 96.0 (p = 0.07) for the SF and LF heifers, respectively; a 5-fold increase for SF heifers. Breeding cycle pregnancy on days 21, 42, and 63, and total percent pregnant did not differ (p>0.10). In drylot, SF heifer dry matter intake (DMI) was 20.1% less (p = 0.001) and feed cost/d was 20.3% lower (p = 0.001), but feed cost/kg of gain did not differ between SF and LF heifers (p = 0.41). Economically important live animal measurements for muscling were measured in May and at the end of the study in October. SF heifers had greater L. dorsi muscle area per unit of BW than LF heifers (p = 0.03). Small frame heifer value was lower at weaning (p = 0.005) and the non-pregnant ending heifer value was lower for SF heifers than for the LF heifers (p = 0.005). However, the total development cost was lower for SF heifers (p = 0.001) and the net cost per pregnant heifer, after accounting for the sale of non-pregnant heifers, was lower for SF heifers (p = 0.004). These data suggest that high breeding efficiency can be attained among March-April born SF and LF virgin heifers when transitioned to a more favorable May-June calving period through the strategic use of grazed and harvested forages resulting in a lower net cost per pregnant SF heifer.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.5
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• pp.640-645
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• 2016

The objective of this study was to evaluate the present conventional selection program of a swine nucleus farm and compare it with a new selection strategy employing genomic enhanced breeding value (GEBV) as the selection criteria. The ZPLAN+ software was employed to calculate and compare the genetic gain, total cost, return and profit of each selection strategy. The first strategy reflected the current conventional breeding program, which was a progeny test system (CS). The second strategy was a selection scheme based strictly on genomic information (GS1). The third scenario was the same as GS1, but the selection by GEBV was further supplemented by the performance test (GS2). The last scenario was a mixture of genomic information and progeny tests (GS3). The results showed that the accuracy of the selection index of young boars of GS1 was 26% higher than that of CS. On the other hand, both GS2 and GS3 gave 31% higher accuracy than CS for young boars. The annual monetary genetic gain of GS1, GS2 and GS3 was 10%, 12%, and 11% higher, respectively, than that of CS. As expected, the discounted costs of genomic selection strategies were higher than those of CS. The costs of GS1, GS2 and GS3 were 35%, 73%, and 89% higher than those of CS, respectively, assuming a genotyping cost of $120. As a result, the discounted profit per animal of GS1 and GS2 was 8% and 2% higher, respectively, than that of CS while GS3 was 6% lower. Comparison among genomic breeding scenarios revealed that GS1 was more profitable than GS2 and GS3. The genomic selection schemes, especially GS1 and GS2, were clearly superior to the conventional scheme in terms of monetary genetic gain and profit.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.7
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• pp.889-897
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• 2011

Mycoplasma Pneumonia of swine (MPS) decreases the daily growth of pigs, and, co-infection with a virus sometimes causes severe pneumonia. Genetic selection of pigs resistant to the pulmonary MPS lesion might solve the economic loss due to MPS in animal production. Here, we examined the immunophenotype of Landrace line (Miyagino L2), genetically selected to reduce the incidence of pulmonary MPS lesion for 5 generations in Miyagi Prefecture Animal Industry Experiment Station. Although this line is expected to be resistant to the pulmonary MPS lesion, the biological characteristics of its immune function are not clear. We investigated details of the immunorelated phenotype of Miyagino L2 at the hematological and molecular biological level, including cytokine expression, and compared the results with that of non-genetically selected Landrace. Miyagino L2 showed decreased antigen-specific IgG and IgM production and increased CD8-positive T-cell population, and high levels of cortisol concentration, suggesting that the MPS-resistant phenotype is associated these immunological differences. Additionally, T-cell CD4 expression was highly correlated with the MPS expected breeding value. Although the detailed mechanisms underlying this high correlation remain unknown, our result suggested that the genetic selection of the expression level of CD4 might be useful to improve MPS resistance in pig production.

• Molecules and Cells
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• v.37 no.2
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• pp.149-160
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• 2014

Plant breeders have focused on improving plant architecture as an effective means to increase crop yield. Here, we identify the main-effect quantitative trait loci (QTLs) for plant shape-related traits in rice (Oryza sativa) and find candidate genes by applying whole genome re-sequencing of two parental cultivars using next-generation sequencing. To identify QTLs influencing plant shape, we analyzed six traits: plant height, tiller number, panicle diameter, panicle length, flag leaf length, and flag leaf width. We performed QTL analysis with 178 $F_7$ recombinant inbred lines (RILs) from a cross of japonica rice line 'SNU-SG1' and indica rice line 'Milyang23'. Using 131 molecular markers, including 28 insertion/deletion markers, we identified 11 main- and 16 minor-effect QTLs for the six traits with a threshold LOD value > 2.8. Our sequence analysis identified fifty-four candidate genes for the main-effect QTLs. By further comparison of coding sequences and meta-expression profiles between japonica and indica rice varieties, we finally chose 15 strong candidate genes for the 11 main-effect QTLs. Our study shows that the whole-genome sequence data substantially enhanced the efficiency of polymorphic marker development for QTL fine-mapping and the identification of possible candidate genes. This yields useful genetic resources for breeding high-yielding rice cultivars with improved plant architecture.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.2
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• pp.176-182
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• 2019

Objective: This study was conducted to investigate basic information on genetic structure and characteristics of Limousin population in Hungary. Obtained results will be taken into consideration when adopting the new breeding strategy by the Association of Hungarian Limousin and Blonde d'Aquitaine Breeders (AHLBB). Methods: Genetic diversity and phylogenetic relationship of 3,443 Limousin cattle from 16 different herds were investigated by performing genotyping using 18 microsatellite markers. Amplified DNA was genotyped using an automated genetic analyzer. Results: Mean of effective alleles ($n_e$) of the populations was 3.77. Population C had the lowest number of effective alleles (3.01) and the lowest inbreeding coefficient ($F_{IS}$) value (-0.15). Principal component analysis of estimated genetic distance ($F_{ST}$) values (p<0.000) revealed two herds (C and E) distinct from the majority of other Limousin herds. The pairwise $F_{ST}$ values of population C compared to the others (0.066 to 0.120) fell into the range of moderate genetic distance: 0.050 to 0.150, while population E displayed also moderate genetic distance ($F_{ST}$ values in range 0.052 to 0.064) but only to six populations (G, H, J, L, N, and P). $F_{ST(C-E)}$ was 0.148, all other pairs -excluding C and E herds- displayed low genetic distance ($F_{ST}$<0.049). Population D, F, I, J, K, L, N, O, and P carried private alleles, which alleles belonged to 1.1% of the individuals. Most probable number of clusters (K) were 2 and 7 determined by Structure and BAPS software. Conclusion: This study showed useful genetic diversity and phylogenetic relationship data that can be utilized for the development of a new breeding strategy by AHLBB. The results presented could also contribute to the proper selection of animals for further whole genome scan studies of Limousins.

• Asian-Australasian Journal of Animal Sciences
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• v.32 no.3
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• pp.334-340
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• 2019

Objective: The objective of this study was to investigate the genetic components of daily milk yield and to re-rank bulls in South Korea by estimated breeding value (EBV) under heat stress using the temperature-humidity index (THI). Methods: This study was conducted using 125,312 monthly test-day records, collected from January 2000 to February 2017 for 19,889 Holstein cows from 647 farms in South Korea. Milk production data were collected from two agencies, the Dairy Cattle Genetic Improvement Center and the Korea Animal Improvement Association, and meteorological data were obtained from 41 regional weather stations using the Automated Surface Observing System (ASOS) installed throughout South Korea. A random regression model using the THI was applied to estimate genetic parameters of heat tolerance based on the test-day records. The model included herd-year-season, calving age, and days-in-milk as fixed effects, as well as heat tolerance as an additive genetic effect, permanent environmental effect, and direct additive and permanent environmental effect. Results: Below the THI threshold (${\leq}72$; no heat stress), the variance in heat tolerance was zero. However, the heat tolerance variance began to increase as THI exceeded the threshold. The covariance between the genetic additive effect and the heat tolerance effect was -0.33. Heritability estimates of milk yield ranged from 0.111 to 0.176 (average: 0.128). Heritability decreased slightly as THI increased, and began to increase at a THI of 79. The predicted bull EBV ranking varied with THI. Conclusion: We conclude that genetic evaluation using the THI function could be useful for selecting bulls for heat tolerance in South Korea.

• Animal Bioscience
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• v.34 no.4
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• pp.575-583
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• 2021

Objective: The aim of the study was to determine the effect of parity and the stage of lactation on the metabolic profile of cows based on the basic chemical milk components and the blood parameters. Methods: The study material consisted of high-yielding Holstein-Friesian cows. In total, 473 cows were examined. According to the parity, cows were divided into four groups: primiparous (P), and multiparous in the second (M2), in the third (M3), and in subsequent lactations (M4). The feeding of cows was based on total mixed ration (TMR) ad libitum. Milk and blood samples were collected individually from each cow three times per standard lactation period. Results: Greater exacerbation of changes in the dynamics of the blood plasma parameters examined was proved for multiparous cows. The highest value of β-hydroxybutyrate acid (0.946 mmol/L) was found for multiparous cows from group M3 at the beginning of lactation. However, it was still in the normal range. The results showed aspartate aminotransferase, and gamma-glutamyl transferase (GGT) activities in dairy cows during lactation had significant variations taking in to account stage of lactation. The highest activity of GGT was found in the group of the oldest cows and measured from 26.36 U/L at the beginning of lactation to 48.75 U/L at the end of the lactation period. Conclusion: The time-related changes in the concentrations of the biochemical parameters described differ markedly among lactating cows, though the housing conditions on the research dairy farm are highly standardised. This indicates that the ability to cope with metabolic stress is mainly affected by the individual predispositions of cows and feed nutrient supply in different stage of lactation. Especially, the feed nutrient supply (in net energy for lactation), which was the best in TMR 1 in comparison TMR 3.

• ALGAE
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• v.36 no.4
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• pp.231-240
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• 2021

Saccharina sculpera is highly valued for human consumption and value-added products. However, natural resources of this kelp have decreased sharply and it is in danger of extinction. Resources recovery through cultivation is being trialed to enable the sustainable use of this species. In this study, the temperature range for survival and optimal growth of juvenile S. sculpera was identified and applied to field cultivation. This study investigated the survival and growth of juvenile S. sculpera under six temperatures (i.e., 5, 10, 15, 16, 18, and 20℃) and two light intensities (i.e., 20 and 40 µmol photons m^-2 s^-1) in an indoor culture experiment. In these experiments, the blade length decreased at 16℃ under the both light intensities. The thalli died at 20℃ and 20 µmol photons m^-2 s^-1, and at 18-20℃ and 40 µmol photons m^-2 s^-1. During the field cultivation, early growth of S. sculpera was highest at the 5 m depth and growth decreased as the water depth increased. When the initial rearing depth was maintained without adjustment throughout the cultivation period (from December to October), all the cultivated S. sculpera plants died during August and September. However, S. sculpera plants lowered from 5 to 15 m and grew to 90.8 ± 13.1 cm in July. The seawater temperature at 15 m depth was similar to the upper level of thermal tolerance demonstrated by juvenile S. sculpera in the indoor culture experiments (16℃ or lower). The plants were subsequently lowered to 25 m depth in August, which eventually led to their maturation in October. The present study confirmed that improved growth rates and a delay in biomass loss can be achieved by adjusting the depth at which the seaweeds are grown during the cultivation period. These results will contribute to the establishment of sustainable cultivation systems for S. sculpera.