본문 바로가기
KERD
논문KCI 등재

Genetic (Co)variance Components for Body Weight and Body Measurements in Makooei Sheep

2

조회

0

다운로드

1

인용

0

참고문헌

키워드

초록

The aim of this paper was to estimate genetic parameters for body weight and five body measurements for an experimental population of Iranian Makooei sheep maintained at the Makooei Sheep Breeding Station at Makoo, Iran. To do this, yearling live weight (YW), and five body measurements, i.e., body length (BL), heart girth (HG), height at withers (HW), height at back (HB) and scrotal circumference (SC), were analyzed in a multi-trait animal model using the DXMUX program of DFREML software package. Heritability estimates were 0.220.08, 0.110.06, 0.210.07, 0.170.06, 0.170.06 and 0.320.10 for YW, BL, HG, HW, HB and SC, respectively. These estimates indicate that selection in Makooei sheep would generate moderate genetic progress in body weight and body measurements. Scrotal circumference, as an indicator of reproductive potential, exhibited the highest heritability. This trait, therefore, could successfully be used to increase productivity of males and, indirectly, female fertility. Genetic correlations between traits studied were all positive and ranged from 0.15 (YW/HB) to 0.99 (HW/HB). Phenotypic correlations were also positive and ranged from moderate (0.32, HW/SC) to high (0.94, HW/HB). Positive genetic and phenotypic correlations indicate that improvement in body measurements both at the genetic and phenotypic levels is expected through selection on body weight and vice versa.

Abstract

The aim of this paper was to estimate genetic parameters for body weight and five body measurements for an experimental population of Iranian Makooei sheep maintained at the Makooei Sheep Breeding Station at Makoo, Iran. To do this, yearling live weight (YW), and five body measurements, i.e., body length (BL), heart girth (HG), height at withers (HW), height at back (HB) and scrotal circumference (SC), were analyzed in a multi-trait animal model using the DXMUX program of DFREML software package. Heritability estimates were 0.220.08, 0.110.06, 0.210.07, 0.170.06, 0.170.06 and 0.320.10 for YW, BL, HG, HW, HB and SC, respectively. These estimates indicate that selection in Makooei sheep would generate moderate genetic progress in body weight and body measurements. Scrotal circumference, as an indicator of reproductive potential, exhibited the highest heritability. This trait, therefore, could successfully be used to increase productivity of males and, indirectly, female fertility. Genetic correlations between traits studied were all positive and ranged from 0.15 (YW/HB) to 0.99 (HW/HB). Phenotypic correlations were also positive and ranged from moderate (0.32, HW/SC) to high (0.94, HW/HB). Positive genetic and phenotypic correlations indicate that improvement in body measurements both at the genetic and phenotypic levels is expected through selection on body weight and vice versa.

참고문헌 (25)

  1. Al-Shorepy, S. A, "Genetic variation and covariation for ewe reproduction, lamb growth and lamb scrotal circumference in a fall-lambing sheep flock", J. Anim. Sci, 74, pp.1490~1498 (1996)
  2. Bathaei, S. S, "Genetic and phenotypic aspects of the growth curve characteristics in Mehraban Iranian fat-tailed sheep", Small Rumin. Res, 29, pp.261~269 (1998)
  3. Blackmore, D. W, "Genetic relationship between body measurements at three ages in Holstein", J. Dairy Sci, 41, pp.1045~1049 (1958)
  4. Bose, S, "Relationship between body measurements and meat production in Beetal goats", Ind. Vet. J, 61, pp.670~673 (1984)
  5. Bourdon, M. R, "Scrotal circumference in yearling Hereford bulls: Adjustment factors, heritabilities and genetic, environmental and phenotypic relationships with growth traits", J. Anim. Sci, 62, pp.958~967 (1986)
  6. Duguma, G., "Genetic parameters of testicular measurements in Merino rams and the influence of scrotal circumference on total flock fertility", S. Afr. J. Anim. Sci, 32, pp.76~80 (2002)
  7. Fogarty, N. M, "Genetic parameters for live weight, fat and muscle measurements, wool production and reproduction in sheep: a review", Anim. Breed. Abs, 63, pp.101~143 (1995)
  8. Fogarty, N. M, "Breed effects and heritability of testis measurements in sheep", J. Anim. Sci, 51(1), pp.117~ (1980)
  9. Fourie, P. J., "Relationship between production performance, visual appraisal and body measurements of young Dorper rams", S. Afr. J. Anim. Sci, 32, pp.256~262 (2002)
  10. Hahn, J., "Testicular growth and related sperm output in dairy bulls", J. Anim. Sci, 29, pp.41~47 (1969)
  11. Horstick, A, "Populationagenetische Untersuchung von Milchleistungs und Exterieurmerkmalen beim ostFriesischen und swarzbraunen Milchschaf", 박사, pp.2001
  12. Janssens, S, "Genetic parameters for body measurements and linear type traits in Belgian Blue du Maine, Suffolk and Texel sheep", Small Rumin. Res, 54, pp.13~24 (2004)
  13. Mandal, A, "Direct and maternal effects for body measurements at birth and weaning in Muzaffarnagari sheep of India", Small Rumin. Res, 75, pp.123~127 (2008)
  14. Matos, C. A. P, "Physiology and genetics of testicular size in sheep: a review", Livest. Prod. Sci, 32, pp.1~30 (1992)
  15. Matos, C. A. P, "Genetic analyses of scrotal circumference, size and growth in Rambouillet lambs", J. Anim. Sci, 70, pp.43~50 (1992)
  16. Meyer, K, "DFREML. Programs to estimate variance components for individual animal models by Restricted Maximum Likelihood (REML). Ver .3.1. Users notes", Animal Genetics and Breeding Unit. University of New England, ~ (2000)
  17. Miraei-Ashtiani, S. R, "Variance components and heritabilities for body weight traits in Sangsari sheep, using univariate and multivariate animal models", Small Rumin. Res, 67, pp.271~278 (2007)
  18. Mohammed, I. D, "Estimating body weight from morphometric measurements of Sahel (Borno White) goats", Small Rumin. Res, 24, pp.1~5 (1996)
  19. Notter, D. R, "Accuracy of estimation of testis weight from in situ testis measures in ram lambs", Theriogenology, 15, pp.227~ (1981)
  20. Salako, A. E, "Application of morphological indices in the assessment of type and Function in sheep", Int. J. Morph, 24, pp.8~13 (2006)
  21. Salako, A. E, "Principal component factor analysis of the morphostructure of immature Uda sheep", Int. J. Morph, 24, pp.571~574 (2006)
  22. STAT User's Guide: Version 9, "SAS", pp.2004, SAS Institute Inc
  23. Smith, B. A, "Relationships of sire scrotal circumference to offspring reproduction and growth", J. Anim. Sci, 67, pp.2881~2885 (1989)
  24. Snyman, M. A, "Direct and maternal (co)variance components and heritability estimates for body weight at different ages and fleece traits in Afrino sheep", Livest. Prod. Sci, 44, pp.229~235 (1995)
  25. Tavakkolian, J, "The genetic resources of native farm animals of Iran" (1999), Animal Science Research Institute of Iran Press

관련 논문AI추천

이 간행물의 다른 논문 (5건)