Evaluation of adjustment methods for environmental effects for weaning weight in Suffolk lambs

Yiming Sulaiman; César Flores-Serrano; Antonio Ortiz-Hernįndez; Rosa Berta Angulo-Mejorada; Hugo H. Montaldo

2009, Number 3

Next >>

Vet Mex 2009; 40 (3)

Evaluation of adjustment methods for environmental effects for weaning weight in Suffolk lambs

Sulaiman Y, Flores-Serrano C, Ortiz-Hernįndez A, Angulo-Mejorada RB,Montaldo HH

Full text

How to cite this article

Language: English/Spanish
References: 20
Page: 219-229
PDF size: 376.47 Kb.

ABSTRACT

Data of weaning weights (WW) from 2 172 Suffolk lambs with complete genealogical information, obtained from a flock in central Mexico from 1992 to 2004, were analyzed using mixed linear models with direct and maternal effects, to generate correction factors and to compare different methods for the adjustment of sex, type of birth and age of the mother effects. The methods compared were: analysis of weaning weights with a complete mixed model (PDMOD), analysis of WW preadjusted to 68 days and for sex and age of the mother-type of birth with factors developed from this population (PD68PRE), analysis of WW adjusted to 68 days with a complete model (PD68MOD) and analysis of WW preadjusted to 68 days and for sex, age of the mother and type of birth with factors developed for the Suffolk population of the United States of America (PD68USA). The effects of year of birth, sex, type of birth, age of the mother, year of birth × age of the mother interaction and the linear and quadratic effects of weaning age were all s ignificant (P ‹ 0.01). The inclusion of all the effects in the model gave slightly smaller residual coefficients of variation with reductions ≤ 0.51%, compared to preadjusted data with correction factors generated either in the flock or adapted from those suggested for the Suffolk population of the United States of America. Small differences between methods in the ranking of the animals according to the genetic evaluations based on empirical BLUP“s for direct and maternal genetic effects were found, with Spearman“s correlation values ≥ 0.96.

REFERENCES

1.SAFARI E, FOGARTY NM, GILMOUR AR. A review of genetic parameter estimates for wool, growth, meat and reproduction traits in sheep. Livest Prod Sci 2004;92:271-289.
2.MAXA J, NORBERG E, BERG P, MILERSKI M. Genetic parameters for body weight, longissimus muscle depth and fat depth for Suffolk sheep in the Czech Republic. Small Rumin Res 2006;72:87-91.
3.NOTTER DR. The U.S. National Sheep Improvement Program: across-flock genetic evaluations and new trait development. J Anim Sci 1998;76:2324-2330.
4.CLEMENT V, BIBE B, VERRIER E, ELSEN JM, MANFREDI E, BOUIX J et al. Simulation analysis to test the influence of model adequacy and data structure on the estimation of genetic parameters for traits with direct and maternal effects. Genet Sel Evol 2001;33:369-395.
5.BIJMA P. Estimating maternal genetic effects in livestock. J Anim Sci. 2006;84:800-806.
6.NOTTER DR, SWIGER LA, HARVEY WR. Adjustment factors for 90-day lamb weight. J Anim Sci 1975;40:383-391.
7.LEWIS RM, SHELTON M, SANDERS JO, NOTTERDR, PIRIE WR. Adjustment factors for 120-day weaning weight in Rambouillet range lambs. J Anim Sci 1989;67:1107-1115.
8.BOUNJENANE I, KERFAL M. Estimates of genetic and phenotypic parameters for growth traits of D“man lambs. Anim Prod 1990;51:173-178.
9.BOGGESS MV, WILSON DE, ROTHSCHILD MF, MORRICAL DG. National sheep improvement program: age adjustment of weaning weight. J Anim Sci 1991;69:3190-3201.
10.WILSON DE, ROTHSCHILD MF, BOGGESS MV, MORRICAL DG. Adjustment factors for birth weight and 30-day, 60-day, and 90-day weaning weight in sheep. J Anim Breed Genet 1996;113:29-41.
11.YAZDI MH, EFTEKHARI-SHAHROUDI F, HEJAZI M, LILJEDAHL LE. Environmental effects on growth traits and fleece weights in Baluchi sheep. J Anim Breed Genet 1998;115:445-465.
12.MATIKA O, VAN WYK JB, ERASMUS GJ, BAKER RL. A description of growth, carcass and reproductive traits of Sabi sheep in Zimbabwe. Small Rumin Res 2003;48:119-126.
13.ASSAN N, MAKUZA SM. The effect of non-genetic factors on birth weight and weaning weight in three sheep breeds of Zimbabwe. Asian Australas J Anim Sci 2005;18:151-157.
14.NOTTER DR, BORG RC, KUEHN LA. Adjustment of lamb birth and weaning weights for continuous effects of ewe age. Anim Sci 2005;80:241-248.
15.RANSOM KP, MULLANEY PD. Effects of sex and someenvironmental factors on weaning weight in sheep. Aust J Exp Agric Anim Husb 1976;16:1923.
16.POWELL RL, NORMAN HD. Major Advances in Genetic Evaluation Techniques. J Dairy Sci 2006;89:1337-1348.
17.AMERICAN SHEEP INDUSTRY ASSOCIATION INC. Sheep production handbook. Denver USA; ADS/ Nightwing Publishing, 2003.
18.RUMPH JM, VAN VLECK LD. Age-of-dam adjustment factors for birth and weaning weight records of beef cattle: a review. Genet Mol Res 2004;3:1-17.
19.GILMOUR AR, GOGEL BJ, CULLIS BR, WELHAM SJ, THOMPSON R. ASReml User Guide. Release 1.0. Hemel Hempstead, HP11ES, UK: VSN International Ltd, 2002.
20.THOMPSON R, BROTHERSTONE S, WHITE IMS. Estimation of quantitative genetic parameters. Philos Trans R Soc Lond B Biol Sci 2005;360:14691477.