• Title/Summary/Keyword: Basic Reproduction Number

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Effect of different parities on reproductive performance, birth intervals, and tail behavior in sows

  • Yang, Ka Young;Jeon, Jung Hwan;Kwon, Kyeong Seok;Choi, Hee Chul;Kim, Jong Bok;Lee, Jun Yeob
    • Journal of Animal Science and Technology
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    • v.61 no.3
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    • pp.147-153
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    • 2019
  • A goal for swine farming is the improvement in the number of live-born and weaned piglets per sow. Hence, the effect of parities should consider the correlation between the component traits of reproductive performance, weaning, and duration. Sows were housed in farrowing pens (W 2.2 ${\times}$ D 1.8 ${\times}$ H 1.2 m) on a partially slatted plastic floor. Twenty sows used in this study were between the first and sixth parity in gilts (P1), parity 2-5 (P3), and parity 6-9 (P6). Data collection by parity was classified into three categories: (1) reproduction performance (gestation length, total number of piglets born, number of piglets live born, number of piglets stillborn, total piglet birth weight; (2) weaning traits (weaning period, number of piglets weaning, total piglets weaning weight); (3) duration traits (farrowing duration, placenta expulsion duration, time from last piglet to first placenta, average birth interval, and tail wagging behavior). Gestation length was higher in P6 than P1 and P3 of different parity sows. The maximum value in P1 and P3 was 117 days, but the median value in P6 was 117 days (p < 0.05). The total number of piglets born (p = 0.113), number of piglets live born (p = 0.118), number of still piglets born (p = 0.151), and total piglet birth weight (p = 0.117) were not affected by parity. The number of live piglets was higher than the other parities by an average of $15.6{\pm}2.1$ in P1. The duration of farrowing was the lowest at 22.2 min in P6, but the maximum value was 42.2 min more than other parities (p = 0.355). Weaning traits of sows also did not differ significantly (p > 0.05), but the weaning period from P1 was lower than that of the other parities (p = 0.170). The number of piglets weaned was 10 heads on average in P1, P3, and P6 (p < 0.05). However, the mean values of the total piglet weaning weight (p = 0.377) of P6 (62.0 10.4 kg) were higher than those of P1 (54.9 10.2 kg) and P3 (58.4 13.6 kg). The placenta expulsion duration was higher in P6 than that in P1 and P3 (p = 0.447). The time from the last piglet to first placenta was be lower in P3 than that of the other parities (p = 0.206). The average birth interval was higher in P3 than that of the other parities (p = 0.156). Tail wagging (count) behavior was higher in P6 than in the other parities (p = 0.065). The data showed that the reproduction performance, total piglets born, and weight were higher in the gilts group, and higher in the weaning trait than that in the P6 group. This study examined the relationship between reproductive performance, birth interval and tail motion according to sow parity. Regarding duration, farrowing duration was lower in P6 than that in the other parities, but placenta expulsion and tail wagging were higher in P6 than in the other parities. Therefore, it is possible that the results from these sows could be used as basic data for effective farm management.

Swell Correction of Shallow Marine Seismic Reflection Data Using Genetic Algorithms

  • park, Sung-Hoon;Kong, Young-Sae;Kim, Hee-Joon;Lee, Byung-Gul
    • Journal of the korean society of oceanography
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    • v.32 no.4
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    • pp.163-170
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    • 1997
  • Some CMP gathers acquired from shallow marine seismic reflection survey in offshore Korea do not show the hyperbolic trend of moveout. It originated from so-called swell effect of source and streamer, which are towed under rough sea surface during the data acquisition. The observed time deviations of NMO-corrected traces can be entirely ascribed to the swell effect. To correct these time deviations, a residual statics is introduced using Genetic Algorithms (GA) into the swell correction. A new class of global optimization methods known as GA has recently been developed in the field of Artificial Intelligence and has a resemblance with the genetic evolution of biological systems. The basic idea in using GA as an optimization method is to represent a population of possible solutions or models in a chromosome-type encoding and manipulate these encoded models through simulated reproduction, crossover and mutation. GA parameters used in this paper are as follows: population size Q=40, probability of multiple-point crossover P$_c$=0.6, linear relationship of mutation probability P$_m$ from 0.002 to 0.004, and gray code representation are adopted. The number of the model participating in tournament selection (nt) is 3, and the number of expected copies desired for the best population member in the scaling of fitness is 1.5. With above parameters, an optimization run was iterated for 101 generations. The combination of above parameters are found to be optimal for the convergence of the algorithm. The resulting reflection events in every NMO-corrected CMP gather show good alignment and enhanced quality stack section.

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Population Characteristics of Echinosophora koreensis (Nakai) Nakai, a Endemic Plants in Korea (한반도 특산식물 개느삼의 개체군 특성)

  • Kim, Sodam;Moon, Ae-Ra;An, Jong-Bin;Jung, Ji-Young;Park, Wan-Geun;Son, Sungwon
    • Korean Journal of Environment and Ecology
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    • v.34 no.1
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    • pp.18-26
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    • 2020
  • Echinosophora koreensis (Nakai) Nakai an endemic plant with limited distribution in some parts of the Korean Peninsula, is designated as "Endangered" species on the IUCN Red List. The species is under the threat of deterioration in nature due to various environmental changes causing loss of natural habitats. We investigated the distribution pattern and population structure of E. koreensis to serve as a basic reference for identifying the dynamics and persistence of natural populations of this species in the future. To determine the characteristics of the E. koreensis population, we laid two to three large plots sized 20m×30m on the ridgeline as the reference in Yanggu, Chuncheon, and Hongcheon and laid four to seven small quadrats sized 1m×1m on the transect. A total of 530 plots were laid, 10 each at 2m interval, to measure the number of the stems, the number of fruiting, height, and other factors. The collected distribution information was compared with the existing IUCN assessed categories by applying IUCN Red List ver 3.1 Criteria B. The average population density of the three surveyed areas was 3.47 stem/㎡; the density of each area was 3.95 stems/㎡ in Yanggu, 3.37 stems/㎡ in Chuncheon, and 2.87 stems/㎡ in Hongcheon. The number of fruiting per stem was 0.0038, indicating only 7 fruits out of 1,837 stems and that vegetative reproduction is likely to be more dominant than sexual reproduction. The distribution tendency of population density in the small plots in three surveyed areas showed that the density of E. koreensis tended to decrease toward the center of the forest with low crown openness and around the mountain ridge with high crown openness. It indicated that the quantity of light could be a very important factor for the growth of individuals of this species. The analysis of the heights of individuals present in the surveyed plots showed a range of 2.3 ~ 68.5cm and an average of 20.1cm. An analysis on the stage-structure of the E. koreensis population based on the sieve height found that the appearance frequency decreased with increasing height above 15 ~ 20cm and that the percentage of individuals lower than 10cm, which were presumed to be seedlings, was severely low, indicating a necessity of study on the population sustainability based on the monitored data. The occupied area calculated with the collected species distribution information was 200㎢, indicating the EN category according to the IUCN Red List Reference B.

Implementation of Phenotype Trait Management System using OpenCV (OpenCV를 이용한 표현체 특성관리 시스템 구현)

  • Choi, Seung Ho;Park, Geon Ha;Yang, Oh Seok;Lee, Chang Woo;Kim, Young Uk;Lee, Eun Gyeong;Baek, Jeong Ho;Kim, Kyung Hwan;Lee, Hong Ro
    • Journal of Korea Society of Industrial Information Systems
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    • v.25 no.6
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    • pp.25-32
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    • 2020
  • The seed, the most basic component, is an important factor in increasing production and efficiency in agriculture. Seeds with superior genes can be expected to improve agricultural productivity, crop survival, and reproduction. Currently, however, screening of superior seeds depends mostly on manual work, which requires a lot of time and manpower. In this paper, we propose a system that can extract the characteristics of seed phenotypes by using computer image processing technology, so that even a small number of people and a short period of time are needed to extract the characteristics of seeds. The proposed system detects individual seeds from images containing large quantities of seeds, and extracts and stores various characteristics such as representative colors, area, perimeter and roundness for each individual seed. Due to the regularity of input images, the accuracy of individual seed extraction in the proposed system is 99.12% for soybean seeds and 99.76% for rice seeds. The extracted data will be used as basic data for various data analyses that reflect the opinions of experts in the future, and will be used as basic data to determine the expressive nature of each seed.

Egg Development and Larvae and Juveniles Morphology of Carp, Cyprinus carpio in Korean

  • Park, Jae Min;Mun, Seong Jun;Yim, Hu Sun;Han, Kyeong Ho
    • Development and Reproduction
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    • v.21 no.3
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    • pp.287-295
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    • 2017
  • This study was conducted to observe egg and larvae morphological development of carp to obtain basic data for resource conservation and taxonomic research. Brood carp used in the research (total length 67.3-75.5 cm, average $71.0{\pm}3.45cm$) were bred in a circular rearing aquarium ($600{\times}300{\times}100cm$) using a running water system from January to July, 2015. Breeding water temperature was maintained at $23.0-25.0^{\circ}C$(average $24.0^{\circ}C$). Fertilized carp eggs were translucent and globular, and their size was 1.75-1.89 mm (average $1.82{\pm}0.06mm$). Blastoderms formed 10 min after fertilization and reached the two-cell stage 30 min after fertilization. Then, the embryo turned dark and exhibited melanophores, and blood started flowing from the heart across the egg yolk at 42 hrs and 50 min after fertilization. Hatching began 70 hrs and 26 min after fertilization larvae emerged through the egg membrane, starting from the head. The length of prelarvae immediately after hatching was 5.23-5.38 mm (average $5.31{\pm}0.11mm$) the mouth and anus were closed, and the pectoral fin was formed. Postlarvae at 18 days after hatching had a total length of 11.9-13.9 mm (average $12.9{\pm}1.40mm$), separate anal fin and back membranes, and fin ray. Juveniles fish at 35 days after hatching had a total length of 29.9-30.2 mm (average $30.1{\pm}0.13mm$), with the body covered with scales, and the same number of fin rays, color, and shape as their broodstork.

An Integrated Epidemiological and Economic Analysis of Vaccination against Highly Pathogenic Porcine Reproductive and Respiratory Syndrome (PRRS) in Thua Thien Hue Province, Vietnam

  • Zhang, Haifeng;Kono, Hiroichi;Kubota, Satoko
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.10
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    • pp.1499-1512
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    • 2014
  • The purposes of this study are to assess pig farmers' preference for highly pathogenic porcine reproductive and respiratory syndrome (PRRS) vaccine, and estimate the cost and benefit of PRRS vaccination in Vietnam. This study employed an integrated epidemiological and economic analysis which combined susceptible-infectious-recovered (SIR) model, choice experiment (CE) and cost-benefit analysis (CBA) together. The result of SIR model showed the basic reproduction number ($R_0$) of PRRS transmission in this study is 1.3, consequently, the optimal vaccination percentage is 26%. The results of CE in this study indicate that Vietnam pig farmers are showing a high preference for the PRRS vaccine. However, their mean willingness to pay is lower than the potential cost of PRRS vaccine. It can be considered to be one of the reasons that the PRRS vaccination ratio is still low in Vietnam. The results of CBA specified from the whole society's point of view (Social perspective), the benefits of PRRS vaccination are 2.3 to 4.5 times larger than the costs. To support policy making for increasing the PRRS vaccination proportion, this study indicates two ways to increase the vaccination proportion: i) decrease vaccine price by providing a subsidy, ii) provide compensation of culling only for PRRS vaccinated pigs.

Osteological Development of the Larvae and Juvenile of Bullhead torrent catfish, Liobagrus obesus

  • Seo, Won-Il;Park, Jae-Min;Lee, Sung-Hun;Yoon, Seong Min;Hwang, Seon-Yeong;Han, Kyeong-Ho
    • Development and Reproduction
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    • v.22 no.1
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    • pp.9-18
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    • 2018
  • This study was conducted to investigate the skeletal development of bullhead torrent catfish, Liobagrus obesus larvae and to utilize them as basic data for the taxonomic study of Liobagrus larvae. Skeletal development was observed by being divided into cranium, visceral skeleton, shoulder girdle bone, pelvic girdle bone and vertebra. On the first day after hatching, the pre-larvae had an average total length of 7.92 mm, and a line-shaped parasphenoid ossified in the cranium. In the jaw bone, the dentary supporting the lower jaw and the maxillary supporting the upper jaw were ossified. In the anterior abdominal vertebrae of the vertebra, seven centrums began to ossify and five neural spines ossified simultaneously. On the 3 day after hatching, pre-larvae had an average total length of 8.95 mm, and the prefrontal ossified in cranium. The number of abdominal vertebrae was increased to 14, and three parapophysis developed from the front side. On the 24th day after hatching, post-larvae had an average total length of 15.2 mm and the epural bone ossified in coccyx. The parhypural bone was ossified, and ossification of coccyx and pelvic girdle bone was completed. On the 30th day after hatching, the average total length of the juvenile was 17.8 mm, and the ossification of cranium and visceral skeleton was all completed while the preorbital and three suborbitals were ossified in the orbital region of the cranium.

Genome-wide association study for intramuscular fat content in Chinese Lulai black pigs

  • Wang, Yanping;Ning, Chao;Wang, Cheng;Guo, Jianfeng;Wang, Jiying;Wu, Ying
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.5
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    • pp.607-613
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    • 2019
  • Objective: Intramuscular fat (IMF) content plays an important role in meat quality. Identification of single nucleotide polymorphisms (SNPs) and genes related to pig IMF, especially using pig populations with high IMF content variation, can help to establish novel molecular breeding tools for optimizing IMF in pork and unveil the mechanisms that underlie fat metabolism. Methods: We collected muscle samples of 453 Chinese Lulai black pigs, measured IMF content by Soxhlet petroleum-ether extraction method, and genotyped genome-wide SNPs using GeneSeek Genomic Profiler Porcine HD BeadChip. Then a genome-wide association study was performed using a linear mixed model implemented in the GEMMA software. Results: A total of 43 SNPs were identified to be significantly associated with IMF content by the cutoff p<0.001. Among these significant SNPs, the greatest number of SNPs (n = 19) were detected on Chr.9, and two linkage disequilibrium blocks were formed among them. Additionally, 17 significant SNPs are mapped to previously reported quantitative trait loci (QTLs) of IMF and confirmed previous QTLs studies. Forty-two annotated genes centering these significant SNPs were obtained from Ensembl database. Overrepresentation test of pathways and gene ontology (GO) terms revealed some enriched reactome pathways and GO terms, which mainly involved regulation of basic material transport, energy metabolic process and signaling pathway. Conclusion: These findings improve our understanding of the genetic architecture of IMF content in pork and facilitate the follow-up study of fine-mapping genes that influence fat deposition in muscle.

Ginsenosides Rb1 and Rg1 Decrease Proliferation but Increase Neuronal Differentiation of Hippocampal Neural Progenitor Cells (진세노사이드 Rb1과 Rg1에 의한 해마 신경전구세포의 분화 증가)

  • Yoon, Young-Ju;Lee, Jun-Seok;Kim, Young-Sook;Yang, Byung-Hwan;Son, Hyeon
    • Development and Reproduction
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    • v.10 no.3
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    • pp.169-175
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    • 2006
  • Ginseng is the best known and most popular herbal medicine used worldwide. In spite of reported beneficial effects of ginseng on the CNS, there is few scientific evidences established at the cellular level. Among more than 30 ginsenosides, Rb1 and Rg1, the active ingredients of ginseng, are regarded as the main compounds responsible for many pharmaceutical actions of ginseng. Daily treatment with Rb1 or Rg1 for 3 d significantly decreased the number of bromodeoxyuridine(BrdU)(+) cells in primary neural progenitor cells(NPCs) isolated from hippocampi at embryonic day 16.5(E16.5). In contrast, treatment with Rb1 or Rg1 greatly increased the number of microtubule associated protein(MAP2) (+) cells. In addition, the transcription factors, Ngn1 and Hes1, proneural members of the basic helix-loop-helix(bHLH) family, significantly increased in Rb1 or Rg1 treated-NPCs. Based on these results, we suggest for the first time that ginsenosides Rb1 and Rg1 decrease proliferation but promote neuronal differentiation of hippocampal NPCs.

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Effects of Raising System on the Reproductive and Weaning Performances in Replacing Gilts (후보모돈의 실내.외 사육방식이 번식 및 이유성적에 미치는 영향)

  • Kim, G.W.;Ok, Y.S.;Kim, S.E.
    • Journal of Animal Environmental Science
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    • v.15 no.1
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    • pp.1-8
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    • 2009
  • This study was conducted to analyze the effects of sow breeding environment on the reproduction in the first litter in a large-sized hog farm, located in Dangjin-gun, Chungnam from July 1st, 2007 to June 30th, 2008 and provide basic information to improve the sow productivity in a family farming sows. The results obtained were as follows; 1. The gestation periods were proved to be similar without significant differences between indoor and outdoor breeding grounds, The average of farrowing rate was 91.91%, and 92.54% farrowing rate of out-door ground breeding sows was slightly greater than 91.57% of group-housed sows, but there was no significance between two groups. 2. The average of total litter size and the number of born alive per litter were 9.81 and 9.02, respectively. The number of total number was 0.98 and the number of born alive per litter was 1.18 in the outdoor-ground breeding sows, which was significantly greater than group-housed sows(p<0.001). 3. The number(rate) of piglets stillborn was 0.22(2.10%) from the outdoor-ground breeding sows was significantly greater, compared with 0.33(3.53%) from group-housed sows(p<0.01). The number of piglets culled was 0.23(2.27%) and 0.26(2.77%), in the out-door ground breeding sows and in group-housed sows, respectively and it was not significantly similar between two groups. And, the number of mummies was 0.21(2.1%) and 0.28(2.29%), in the out-door ground breeding sows and in group-housed sows, respectively, which showed no significance. 4. The weaning number in the playground breeding sows was 9.48 and it was significantly greater than that in the group-housed sows(p<0.001). The average of weaned age was observed to be 22.91 days. The weaned age in the out-door ground breeding sows was 22.39 days, and it was significantly smaller than that in group-housed sows(p<0.001). The breeding rate for the weaning of pigs was satisfactory as 96.82%, but there was no significant difference between two groups.

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