• Asian-Australasian Journal of Animal Sciences
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• v.9 no.5
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• pp.591-595
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• 1996

This paper presents results from a study of the age and weight at puberty of Thai does. A randomized block $3{\times}3$ factorial design was used. Factors were genotype (Thai Native; TN, 75% TN $\times$ 25% Anglo-Nubian; AN and 50 TN $\times$ 50% AN does), year of kidding (1989, 1990 and 1991) and birth type (single or twin) as a block. It was shown that there were no significant (p > 0.05) difference in age at puberty among genotypes ($167.6{\pm}6.0$, $157.6{\pm}7.0$ and 160.0 = 4.7 days for TN, 75% TN $\times$ 25% AN and 50% TN $\times$ 50% AN does, respectively) and between birth types. However, does kidded in 1991 had significantly (p < 0.01) longer age at puberty ($194.0{\pm}7.4$ days) than did does kidded in 1989 ($143.0{\pm}4.5$ days) or in 1990 ($148.1{\pm}5.7$ days). There was an interaction effect between genotype and year. Fifty % TN $\times$ 50% AN does had significantly (p < 0.05) higher weights at pubery ($17.2{\pm}0.4kg$) than those of TN($14.3{\pm}0.5kg$ and 75% TN $\times$ 25% AN ($14.4{\pm}0.6kg$) does. There was no significant difference in weights at puberty between TN and 75% TN $\times$ 25% AN does. There was no effect of birth type on weight at puberty. There was an interaction effect between genotype and year of kidding on age and weight at puberty and on growth rate from birth to weaning.

• Clinical and Experimental Pediatrics
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• v.49 no.7
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• pp.718-725
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• 2006

The pubertal activation of gonadotrophin releasing hormone(GnRH) requires coordinated changes in excitatory or inhibitory amino acids, growth factors, and a group of transcriptional regulators. The age of onset of puberty is progressing to younger age. Factors affecting early puberty include genetic traits, nutrition(body fat) and exposure to endocrine disrupting chemicals. In rapidly progressing central precocious puberty, gonadotrophin releasing hormone(GnRH) agonists(GnRHa) appear to increase final height if treated early stage. Further large scaled long-term follow-up study of the effects of GnRHa on final height is needed.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.2
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• pp.182-187
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• 2010

The aim of this experiment was to evaluate the levels of hormones (progesterone, IGF-I and IGFBP-3) in blood plasma, growth, carcass traits and their interactions of sexually immature (n = 18) and sexually mature (n = 17) gilts. To calculate average daily weight gain (ADG), gilts were individually weighed at the beginning of the trial and at slaughter (110${\pm}$10 days old). Blood concentrations of progesterone, IGF-I and IGFBP-3 were determined by RIA. The right hot carcass sides were dissected and the individual basic parts from carcasses were weighed to record the carcass traits. IGFBP-3, ADG and carcass traits were not affected by pubertal maturation. Compared to sexually immature gilts, mature gilts had higher blood concentrations of progesterone and IGF-I. High correlations were noted between levels of some hormonal substances, productive performance and carcass traits of sexually immature and mature gilts.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.8
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• pp.1109-1115
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• 2008

The reproduction component traits are important components of sow efficiency. The objective of this study was to evaluate the phenotypic and genetic parameters of four reproduction component traits (age at puberty (AP), preweaning number dead (PND), weaning to service interval (WSI), and intra-individual SD in litter size (IISDLS)) of sows in two Chinese indigenous pig breeds. Available reproductive records including 22,591 piglets born from 2,054 litters by 574 Jiangquhai sows and 464 Meishan sows were used in this investigation. A set of mixed models and restricted maximum likelihood methodology were used for the multiple trait analyses of these traits. The results showed that the estimates of heritabilities (${\pm}$standard error) for AP, PND, WSI and IISDLS were $0.40{\pm}0.05$, $0.06{\pm}0.03$, $0.20{\pm}0.02$ and 0.09{\pm}0.03 in Jiangquhai sows, and $0.35{\pm}0.06$, $0.05{\pm}0.03$, $0.18{\pm}0.03$ and $0.10{\pm}0.04$ in Meishan sows, respectively. There was moderate genetic correlation between AP and WSI, while there were low genetic correlations between the other pairwise traits. The genetic correlations were positive for most of the pairwise traits, except for the one between AP and IISDLS. The results indicated that all traits except for AP were difficult to make genetic improvement by traditional selection methods due to low heritabilities and the favorable improvement of AP might result in unfavorable changes of IISDLS due to the trend of genetic antagonism.

• Journal of Agricultural Extension & Community Development
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• v.14 no.2
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• pp.471-491
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• 2007

The purpose of this study were (1) to thumbnail sketch of present general condition of foreigners and international marriage in Korea, (2) to study special trend of international marriage in rural Korea, particularly immigration connected with poverty, and (3) to focus on prospect of the problem of mixed-bloods, especially half blood children in rural Korea. Many of foreigners were treated discriminatingly, for example racial discrimination and wage discrimination. And discrimination to mixed-blood children will be happen in future. They are in a disadvantageous position because of economic status and appearances. Half blood children have korean nationality because one of his parent is korean. When they grow up and reach their the age of puberty and the age of working, they will resist to discrimination in working and marriage. I had examined precedent studies, and class theory in general, and to suggest it is time to looking for way of reduce social cost and way of coexistence.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.4
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• pp.462-469
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• 2017

Objective: The aim of this study is to identify genomic regions or genes controlling growth traits in pigs. Methods: Using a panel of 54,148 single nucleotide polymorphisms (SNPs), we performed a genome-wide Association (GWA) study in 562 pure Yorshire pigs with four growth traits: average daily gain from 30 kg to 100 kg or 115 kg, and days to 100 kg or 115 kg. Fixed and random model Circulating Probability Unification method was used to identify the associations between 54,148 SNPs and these four traits. SNP annotations were performed through the Sus scrofa data set from Ensembl. Bioinformatics analysis, including gene ontology analysis, pathway analysis and network analysis, was used to identify the candidate genes. Results: We detected 6 significant and 12 suggestive SNPs, and identified 9 candidate genes in close proximity to them (suppressor of glucose by autophagy [SOGA1], R-Spondin 2 [RSPO2], mitogen activated protein kinase kinase 6 [MAP2K6], phospholipase C beta 1 [PLCB1], rho GTPASE activating protein 24 [ARHGAP24], cytoplasmic polyadenylation element binding protein 4 [CPEB4], GLI family zinc finger 2 [GLI2], neuronal tyrosine-phosphorylated phosphoinositide-3-kinase adaptor 2 [NYAP2], and zinc finger protein multitype 2 [ZFPM2]). Gene ontology analysis and literature mining indicated that the candidate genes are involved in bone, muscle, fat, and lung development. Pathway analysis revealed that PLCB1 and MAP2K6 participate in the gonadotropin signaling pathway and suggests that these two genes contribute to growth at the onset of puberty. Conclusion: Our results provide new clues for understanding the genetic mechanisms underlying growth traits, and may help improve these traits in future breeding programs.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.6
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• pp.581-586
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• 1997

The present study analysed the various productive and reproductive characteristics of 1/2 Pabna Milking Cows (PMC)-1/2 Sahiwal (S) and 1/4 PMC-3/4 S collected from the Pabna milkshed area at Baghabarighat, Sirajgonj, Bangladesh. The studied traits were birth weight (BWT), age at puberty (AP), number of services per conception (NSC), post partum heat period (PPHP), gestation period (GP), daily milk yield (DMY), lactational production (LP), lactation length (LL), fat percentage and solids-not-fat percentage (SNFP). Five individual Sahiwal sires were used for the upgrading of Pabna Milking Cows. The used data covered from 1987 to 1994. Least-squares analysis of variance showed that genetic group had a significant effect on BWT (P < 0.05), AP (p < 0.01), DMY (p < 0.01), LP (p < 0.001), LL (p < 0.05), FP (p < 0.05) and SNFP (p < 0.01). Genetic group had non-significant effect on NSC, GP and PPHP. The effect of sire was significant on BWT (p < 0.01), NSC (p < 0.01), LP (p < 0.05) and LL (p < 0.05). The AP, NSC, DMY, LP, LL and SNFP were higher in 1/2 PMC-1/2S cows; BWT and PPHP were higher in 1/4 PMC-3/4S but GP and FP were almost same in both genetic groups. From this study it may be concluded that production and use of 1/2 PMC-1/2S would seem more profitable for commercial milk production in the Bangladesh Milk Producers' Cooperative Union Limited (BMPCUL) area and at the same time emphasis should be given on rigorous sire selection.

• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.55-61
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• 1985

This study was carried out to investigate reproductive traits and sex hormone levels by growth in Korean native goats. Serum levels of FSH, LH, prolactin, estradiol-$17{\beta}$ and progesterone were determined every 15 days from the 70 days of age to 190 days by radioimmunoassay. The age and weight at sexual maturity were 183.6 days and 14.3 kg; the length of estrous cycle and estrus period were 20.3 days and 36.7 hours, respectively. The gestation period, litter size and body weight at birth were 148.4 days, 1.4 head and 1.8 kg, respectively. The levels of serum LH were highest with 3.93 mIU/ml at 70 days of age, thereafter decreased gradually to 1.21 mIU/ml at 190 days of age. The concentrations of FSH in serum were below 1.25 mIU/ml throughout the experimental period. The levels of prolactin were lowest with 3.09ng/ml at 85 days of age and highest with 4.65 ng/ml at 175 days of age. The serum levels of estradiol-$17{\beta}$ were increased with age, thus highest with 7.95 pg/ml at 190 days of age. The serum progesterone concentrations were maintained low levels (below 1.0 ng/ml) throughout the experimental period.