• Title/Summary/Keyword: Body size trait

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A Study on the Body Type of Hanwoo(Korean Cattle) Steer by Using Principal Components Analysis (주성분 분석을 이용한 거세한우의 체형분류에 관한 연구)

  • Ha, D.W.;Kim, H.C.;Kim, B.W.;Lee, M.Y.;Lee, J.H.;Shin, C.K.;Do, C.H.;Lee, J.G.
    • Journal of Animal Science and Technology
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    • v.44 no.6
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    • pp.643-652
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    • 2002
  • Data were consisted of the ten body measurements (withers height, rump height, body length, chest depth, chest width, rump width, rump length, thurls width, hipbone width and chest girth) of 642 steers (Korean cattle), which was entered in the National Beef Quality Contest hosted by the Korea Animal Improvement Association from 1997 to 2001. A principal components analysis was used to classify the body types of the steers, and estimate the correlations between carcass traits and principal components for the body measurements of the first, second, third and fourth period, respectively. The first principal component of body measurements at the first, second, third and fourth period accounted for 76.0%, 83.0%, 72.7% and 57.4% of the total variance, respectively. The sum of first, second and third principal component at each period accounted for 86.69%, 90.49%, 84.62% and 77.26% of the total variance, respectively. At each period, all the first principal component of the body measurements were positive and it generally showed large framed body shape. The size of body was influenced mostly by chest depth(0.328${\sim}$0.339) and rump length(0.325${\sim}$0.341). The second, third and fourth principal component at the each period were various. There were positive correlations between principal components index of each period and carcass traits such as carcass weight(0.539${\sim}$0.755), average daily gain(0.256${\sim}$0.564), backfat thickness(0.227${\sim}$0.280), and eye muscle area(0.187${\sim}$0.344). The correlation with yield grade index(-0.246${\sim}$-0.110), however, was negative. The correlation with marbling score(0.066${\sim}$0.099) was low or statistically insignificant. According to principal component indexes of the second, third, and fourth components, the correlations with the carcass traits were various. There were no large differences between the correlations of the single body measurement trait with the carcass traits and the correlations of the first principal component indexes with the carcass traits.

Characteristics of External and Cranial Morphological Characters of Asian Lesser White-Toothed Shrew (Crocidura shantungensis) (작은땃쥐 (Crocidura shantungensis)의 외부 형태 및 두개골 형질의 특성)

  • Kim, Tae-Wook;Park, Su-Gon;Kim, Yoo-Kyung;Park, Jun-Ho;Adhikari, Pradeep;Kim, Ga-Ram;Park, Seon-Mi;Lee, Jun-Won;Han, Sang-Hyun;Oh, Hong-Shik
    • Korean Journal of Environmental Biology
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    • v.33 no.4
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    • pp.441-449
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    • 2015
  • This study was conducted to screen the characteristics of external and cranial characters of Crocidura shantungensis collected from Korean Peninsula, Ulleung Island and Jeju Island. There were significant differences in head-body length (HBL), tail length (TL), ear length (EL), and hind foot length (HFL) in males and HBL, TL, and HFL in females among three populations (p<0.05). The HBL and TL in the Jeju Island population were larger (8.0 mm and 4.0 mm in lengths, respectively) than those of the Korean Peninsula population. Based on skull analysis, a total of thirteen traits showed significant differences among the three populations (p<0.05). The condylo-insicive length (CIL), maximum width of brain case (MWB), mandibular length (ML), and mandibular height (MH) in the Jeju Island population were significantly larger than those of Korean Peninsula population (p<0.05). Principle component analysis (PCA) showed that two principle components (PC) identified from the PCA affected on the body size and width of the skull, respectively. Discriminant analysis revealed that these populations could be discriminated through skull traits. These findings concluded that the Jeju Island population was greater in the size than the Korean Peninsula, suggesting that the Jeju Island shrews have successfully adapted to the island environments and they had morphologically differentiated during glacial period after natural immigration into that Island. Thus, this study supports the 'Island Rule', showing that the population is well adapted to the island environments. This may provide important information for biogeographical and ecological studies on insular animals.

Study on Genetic Evaluation for Linear Type Traits in Holstein Cows

  • Lee, Deukhwan;Oh, Sang;Whitley, Niki C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.23 no.1
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    • pp.1-6
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    • 2010
  • The objectives of this study were to i) investigate genetic performance for linear type traits of individual Holstein dairy cows, especially focusing on comparative traits, and to estimate genetic variances for these traits using actual data, and ii) compare genetic performance and improvement of progeny by birth country of the cows. Linear type traits defined with five comparative traits on this study were general stature composite (GSC), dairy capacity composite (DCC), body size composite (BSC), foot and leg composite (FLC), and udder composite (UDC). These traits were scored from 1 to 6 with 1 = poor, 2 = fair, 3 = good, 4 = good plus, 5 = very good and 6 = excellent. Final scores (FS) were also included in this study. Data used was collected from the years 2000 to 2004 by the Korea Animal Improvement Association (KAIA). Only data of more than five tested cows by herd appraisal date and by sires having more than ten daughters were included to increase the reliability of the data analyses. A total of 30,204 records of the selected traits, which was collected from 26,701 individuals having pedigree information were used. Herd appraisal date, year of age, lactation stage (grouped by month), and time lagged for milking (in hours) were assumed as fixed effects on the model. Animal additive genetic effects considering pedigree relationship and residual errors were assumed with random effects. Year of age at appraisal date was classified from one to nine years of age, assigning the value of nine years of age for animals that were greater than or equal to nine years of age. From our results, the estimate for heritability was 0.463, 0.346, 0.473, 0.290, and 0.430 on GSC, DCC, BSC, FLC and UDC, respectively. The estimate for FS heritability was 0.539. The greatest breeding values for GSC were estimated for Canada, with the breeding values for American lines increasing for 10 years starting in 1989 but tending to decrease after that until 2004. For DCC, the breeding values for American and Canadian lines showed similar patterns until 1999, after which the breeding values for the American lines declined sharply. For BSC, data from Korea, Canada and the USA followed similar trends overall except when the breeding values of the American lines decreased starting in 1999. Overall, the methods used to evaluate genetic performance in this study were acceptable and allowed for the discovery of differences by country of genetic origin, likely due in part to the American use of selection indexes based primarily on milk yield traits until methods for evaluating other traits began to emerge.

An Analysis on the Factors Affecting University Startups (대학 창업 성과에 미치는 영향 요인)

  • Kim, Jongwoon
    • Korean small business review
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    • v.42 no.4
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    • pp.285-308
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    • 2020
  • This paper analyzes the factors which affect University professors and students on their startup activities, such as (a) University factors: their industrial cooperation organization and systems, their resources for startup support, their knowledge assets, and (b) socioeconomic characteristics in which Universities are located. We used the data and information from the University Information System and the National Statistical Office Publication to analyze 157 4-year Universities in Korea who uploaded their startup-related information on the system. Our analysis shows that Universities' systems, such as the term for Professors' leave of absence for startup activities, and their amount of knowledge assets affect the number of Professor startups significantly positively, while there is no significant effect on their performance, in terms of sales, from those factors, except for the amount of patents that the University has. In the meantime, the number of practical startup courses, the number of startup clubs, and the number of professor startups in the University affect the number of student startups, while the size of industrial cooperation body, the amount of knowledge asset, the area's socioeconomic characteristics didn't affect their performance. The result implies that we need to take different approaches to boost University professor startups and their student startups: better system and more knowledge for the former, more practical courses and programs for the latter. Further study is needed to get a more robust result because this analysis used only one year data, and personal trait data was not included in the analysis. A panel data analysis for several years is recommended for further research.

Parameter estimation and assessment of bias in genetic evaluation of carcass traits in Hanwoo cattle using real and simulated data

  • Mohammed Bedhane;Julius van der Werf;Sara de las Heras-Saldana;Leland Ackerson IV;Dajeong Lim;Byoungho Park;Mi Na Park;Seunghee Roh;Samuel Clark
    • Journal of Animal Science and Technology
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    • v.65 no.6
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    • pp.1180-1193
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    • 2023
  • Most carcass and meat quality traits are moderate to highly heritable, indicating that they can be improved through selection. Genetic evaluation for these types of traits is performed using performance data obtained from commercial and progeny testing evaluation. The performance data from commercial farms are available in large volume, however, some drawbacks have been observed. The drawback of the commercial data is mainly due to sorting of animals based on live weight prior to slaughter, and this could lead to bias in the genetic evaluation of later measured traits such as carcass traits. The current study has two components to address the drawback of the commercial data. The first component of the study aimed to estimate genetic parameters for carcass and meat quality traits in Korean Hanwoo cattle using a large sample size of industry-based carcass performance records (n = 469,002). The second component of the study aimed to describe the impact of sorting animals into different contemporary groups based on an early measured trait and then examine the effect on the genetic evaluation of subsequently measured traits. To demonstrate our objectives, we used real performance data to estimate genetic parameters and simulated data was used to assess the bias in genetic evaluation. The results of our first study showed that commercial data obtained from slaughterhouses is a potential source of carcass performance data and useful for genetic evaluation of carcass traits to improve beef cattle performance. However, we observed some harvesting effect which leads to bias in genetic evaluation of carcass traits. This is mainly due to the selection of animal based on their body weight before arrival to slaughterhouse. Overall, the non-random allocation of animals into a contemporary group leads to a biased estimated breeding value in genetic evaluation, the severity of which increases when the evaluation traits are highly correlated.

External and Cranial Characters of the Tscherskia triton in Jeju Island, Korea (제주도에 서식하는 비단털쥐 (Tscherskia triton)의 외부형태 및 두개골 특징)

  • Park, Jun-Ho;Oh, Hong-Shik
    • Korean Journal of Environmental Biology
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    • v.35 no.3
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    • pp.389-397
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    • 2017
  • The purpose of this study was to investigate the characteristics of species by comparing the external shape traits and skull size of Tscherskia triton in Jeju Island from May 2014 to November 2016. Body weight, head-body length, ear length, and hind-foot length were not statistically significant (p>0.05), but tail length was statistically significant in females compared to males (p=0.003). To examine the secondary sexual dimorphism characteristics of the collected T. triton, B_HR, T_HR, E_HR, and H_HR were calculated based on the head-body length, and only T_HR was statistically significant (p=0.003). Because of comparing male and female averages, among the 21 traits, the greatest length of skull (GLS; p=0.020) and occipitonasal length (ONL; p=0.014) were statistically significant and length of incisive foramen (LIF) was statistically significant, when the significance level was 90%. However, the other 18 traits did not show statistically significant differences between males and females (p>0.05). Other than GLS, ONL, interorbital breadth (IB), and breadth of occipital foramen (BOF), there was female-biased SSD. The results of this study are the analysis of external morphology and skull characteristics of T. triton in Jeju Island and will be used as basic data to understand the morphological characteristics of T. triton. In addition, the data can be used as a basic information to compare characteristics of T. triton, which is known as a single species, inhabited in China and Russia. The data will play an important role in biogeography and ecology research of T. triton, based on geographical conditions, climate effects, and habitat environment.