• 농업과학연구
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• 제45권2호
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• pp.238-247
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• 2018

The overall consumption of meat is increasing as the level of national income increases. The end weight is a trait closely associated with dressed meat. Genome-wide association study (GWAS) is an effective method of analyzing genetic variation and gene identification associated with a number of natural alternative traits because it can detect variations. So this paper did a GWAS analysis to identity the location on the genome related to the end weight in purebred landrace pigs and to explore the relevant candidate gene. This study identified a significant single nucleotide poly morphism (SNP) marker in chromosome 6 (ASGA0029422, $p=1.22{\times}10^{-6}$). Adhesion G protein-coupled receptor L2 (ADGRL2) was found to be the candidate gene at the identified SNP marker location. ADGRL2 genes have been found to be associated with cell development in relation to the external and internal environment of a cell. In addition, genotype and statistical analyses were done on nine variations on the exon of ADGRL2. The results show that the SNP marker (ASGA0029422, $p=1.32{\times}10^{-6}$) was significant, but the significance of the nine variations on the ADGRL2 exon was not verified. However, by performing further experiments and functional studies on other SNPs showing possible genetic ADGRL-Exon mutations, objects with high associations of high-end weights can be selected.

• 한국축산식품학회지
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• 제42권3호
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• pp.398-410
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• 2022

We studied effects of aging methods and temperature on the physical, chemical, and amino acid composition of pork belly from Berkshire and Landrace×Yorkshire×Duroc (LYD) swine. Pork belly samples were assigned randomly to breed groups (Berkshire and LYD), aging temperature groups (0℃ and 9℃), and aging method groups. One samples of vacuum-packaged hanging pork bellies were hung in a refrigerated cooler with 83±2.0% humidity, while the other samples were immersed in a 3.5% salt solution in a vacuum package and subsequently stored in the same cooler for 2 weeks. LYD pork had lower pH and purge loss and higher lightness values than those of Berkshire pork (p<0.05). Moreover, thiobarbituric acid reactive substances and hardness values of LYD pork were lower than those of Berkshire pork after aging (p<0.05). Berkshire pork had a higher level of flavorful amino acids than LYD pork did during aging (p<0.05). Bellies aged at elevated temperatures for two weeks had higher volatile basic nitrogen. However, significantly higher percentages of flavorful and sweet taste amino acids were observed in bellies aged at 9℃ compared to those aged at 0℃ for 2 weeks. Moisture content was higher in immersed samples than hanging samples after two weeks of aging (p<0.05). Hanging pork bellies exhibited higher texture profiles than immersed pork bellies at two weeks (p<0.05). We concluded that breeds, aging temperature, and methods affected most quality attributes of pork belly.

• 농업과학연구
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• 제43권4호
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• pp.612-622
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• 2016

The purpose of this study was to evaluate the effects of sex, birth year, birth season, and parity of sows on their progeny using the following on-farm test records: Backfat Thickness (BF), Fresh Meat Percent (FMP), Loin depth (LD), Age at 90kg (90D), and Average Daily Gain (ADG). Statistical analysis was performed using data collected from 1,178 Yorkshire and 13,395 Landrace progenies, which were born from 119 Yorkshire and 1,191 Landrace sows, respectively between 2011 and 2015. All results of the analysis were statistically significant (P < 0.05) except the birth season effect on LD. For Landrace, the highest ratings were found to be at the $5^{th}$ parity (BF), at the $3^{rd}$ parity (FMP and LD), at the $2^{nd}$ parity (90D and ADG). For Yorkshire, the highest ratings were at the $2^{nd}$ parity (BF and FMP), at the $3^{rd}$ parity (LD), and at the $4^{th}$ parity (90D and ADG). Although the ratings of carcass traits of progeny appear to be higher between the maternal sow's $2^{nd}$ and $4^{th}$ progenitor, no significant relations to parity were found. Based on these results, we concluded that maternal parity is not significantly affect carcass traits of progeny and thus that the best slaughtering age of sows should not be determined solely based on maternal parity but also in consideration of other factors such as unit costs of production. The results of this study would provide fundamental information to future studies on the effect of economical parity on sows and swine breeding.

• 한국수정란이식학회지
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• 제28권4호
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• pp.315-318
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• 2013

This study was conducted to investigate the changes of hormone levels of serum progesterone (P4) and estradiol-$17{\beta}$ (E2) in sows of Landrace (L), Yorkshire (Y) and F1 (L ${\times}$ Y) (respectively n=3) with excellent ability, and to provide a baseline data for improving reproductive performance. In this experiment, the sows at the age of 12 months or more were used. The sows were fed by two way methods, one is conventional methods and the other is 3 days-flushing feed before estrus. Each pig's blood was collected in 3, 6, 9, 12, 15 and 18 days after the estrus for the analyses of P4 and E2. Serum was separated by centrifugation for 15 min. with 3,000 rpm. Progesterone and estradiol-$17{\beta}$ were measured by immunochemical assay (ELIZA test). In conventional feeding, serum progesterone levels were significantly (p<0.01) higher in F1 than in L and Y. No significant differences in P4 concentrations were seen between the L and Y of sows. Serum E2 levels were similar the serum progesterone levels. In the case of flushing feed, the tendency of hormonal changes were similar to conventional methods. But almost of hormonal levels were a little higher than that of conventional methods. P4 level of L and Y in flushing feed were significantly different (p<0.01). Serum E2 level of Y in flushing feed was significantly different among the breeds (p<0.01). These results were similar to the tendency of hormonal changes in general sows and moreover, flushing feed is known to develop the swine production, these results proved the fact of the methods. And these results suggested that more studies about hormonal changes in sows according to seasonal and nutritional factors should be needed.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.196-196
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• 2022

• Parasites, Hosts and Diseases
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• 제30권4호
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• pp.269-276
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• 1992

• Journal of Animal Science and Technology
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• 제61권2호
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• pp.109-109
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• 2019

• 한국가축번식학회지
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• 제27권4호
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• pp.281-285
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• 2003

This study was carried out to find out the changes on serum concentrations of estradiol-17$\beta$, progesterone in primiparous Duroc, Landrace and Yorkshire sows weaned at 7 or 21 days. Also, we compared the litter size at birth and weaning among the breeds weaned after lactation for 7 or 21 days. The estradiol-17$\beta$ concentrations among the breeds were 6.9∼8.8 pg/ml and 6.4∼8.8 pg/ml after lactation for 7 or 21 days, respectively. The progesterone concentrations ranged from 0.3 ng/ml to 1.6 ng/ml. Duroc sow showed higher progesterone concentration compared with Landrace and Yorkshire sows weaned after lactation for 7 or 21 days. Also, we found out that litter size at birth and weaning, respectively, did not show any differences between day 7 and day 21 of lactation. From the facts mentioned above, it was suggested that very early weaning systems could work with no apparent adverse effect on prolificacy.

• 한국가축번식학회지
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• 제8권2호
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• pp.92-96
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• 1984

This study was carried out ot examine the sex ratios of offspring in swine. The sex ratios were obtained on the basis of the data from 15,892 pigs produced by 1,728 litters of Landrace, Large Yorkshire, Hampshire and Duroc breeds at National Animal Breeding Institute from 1975 to 1980. The results obtained are summarized as follows: 1. The sex ratio of total offspring was 51.47% for male and significant at 5% level, and Landrace and Duroc breeds were 51.46% and 52.27% for male and significant at 5% level, respectively, but no significant difference between the breeds. 2. The sex ratio of offspring by years was 52.74% for male and significant at 5% level in 1979, but no significant difference for other years and between years. 3. The sex ratio of offspring by seasons were a little highly 51.65% and 51.25%, for male in spring and autumn, but no significant difference, respectively. 4. The sex ratio of offspring by parities were 52.65% and 55.81% for male in groups of the 3rd to 4th and the 5th to 6th parity, and significant difference at 5% and 1% level, respectively. 5. The sex ratio of offspring by groups of litter size was 52.65% for male in 1 to 6 heads group, and significant difference at 5% level, but no significant difference between groups of litter size.

• Animal Bioscience
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• 제37권5호
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• pp.807-816
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• 2024

Objective: This study aims to identify the significant regions and candidate genes of growth-related traits (adjusted backfat thickness [ABF], average daily gain [ADG], and days to 90 kg [DAYS90]) in Korean commercial GGP pig (Duroc, Landrace, and Yorkshire) populations. Methods: A genome-wide association study (GWAS) was performed using single-nucleotide polymorphism (SNP) markers for imputation to Illumina PorcineSNP60. The BayesB method was applied to calculate thresholds for the significance of SNP markers. The identified windows were considered significant if they explained ≥1% genetic variance. Results: A total of 28 window regions were related to genetic growth effects. Bayesian GWAS revealed 28 significant genetic regions including 52 informative SNPs associated with growth traits (ABF, ADG, DAYS90) in Duroc, Landrace, and Yorkshire pigs, with genetic variance ranging from 1.00% to 5.46%. Additionally, 14 candidate genes with previous functional validation were identified for these traits. Conclusion: The identified SNPs within these regions hold potential value for future marker-assisted or genomic selection in pig breeding programs. Consequently, they contribute to an improved understanding of genetic architecture and our ability to genetically enhance pigs. SNPs within the identified regions could prove valuable for future marker-assisted or genomic selection in pig breeding programs.