+ Site Statistics
+ Search Articles
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ PDF Full Text
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Translate
+ Recently Requested

Genetic and phenotypic parameter estimates for selection to improve lamb carcass traits

Genetic and phenotypic parameter estimates for selection to improve lamb carcass traits

New Zealand Journal of Agricultural Research 35(3): 287-298

The variance components needed to calculate genetic and phenotypic parameters for selection to improve carcass composition in white-faced sheep were estimated from a sire model using REML on data from 1602 Romney and Romney-cross lambs. The sires were either Romney (n = 60), Border Leicester (n = 18), Poll Dorset (n = 14), or Coopworth (n = 10) with approximately 16 progeny per sire and all dams were Romney. Lambs had an average liveweight of 31.0 kg at an average age of 205 days. Carcasses were dissected into lean, subcutaneous fat, intermuscular fat, bone, and waste. The multivariate mixed linear model included birth date of the lamb as a linear covariate, year-rearing group, breed of sire, sex of lamb, birth rank, and slaughter group as fixed effects, and sire as a random effect. Traits were categorised as either lean, fat, or skeletal dimension indicators. Heritability estimates for lean indicator traits obtained by dissection averaged 0.36. The lean indicator trait with the highest heritability was longissimus muscle width (h-2 = 0.63). Heritability estimates for fat depth measurements averaged 0.23. Heritability of skeletal dimension traits averaged 0.43. Expected responses in a selection objective, comprising increased lean weight and decreased fat weight, were compared for selection indices consisting of hot-carcass weight and one of 26 carcass measurements. In general, both lean and fat indicator traits contributed to a reduction in fat response. The index comprising hot-carcass weight and weight of lean tissue, obtained by dissection, from the leg joint, produced the greatest economic response in the selection objective. The economic response from a nondissection trait was from selection on the index which comprised hot-carcass weight and logissimus muscle width, A. The increase in lean tissue response over that predicted from single trait selection on HCW was small (0.04 kg) relative to the decrease in FAT (0.20 kg). None of the dimension traits produced a negative predicted response in fat. In the range of predicted responses from the two trait indices, there was greater variation in the fat responses than in the lean responses.

(PDF emailed within 0-6 h: $19.90)

Accession: 002390372

Download citation: RISBibTeXText

DOI: 10.1080/00288233.1992.10427506

Related references

Genetic and phenotypic parameter estimates for growth and carcass value traits of sheep. Archiv fuer Tierzucht 41(5): 463-472, 1998

Genetic and phenotypic parameter estimates for feed intake and other traits in growing beef cattle, and opportunities for selection. Journal of Animal Science 89(11): 3452-3459, 2012

The value of selection for carcass traits to improve lamb carcass yield and quality. Journal of Animal Science 96: 192-193, 2018

Selection for components of efficient lean growth rate in pigs: 4. Genetic and phenotypic parameter estimates and correlated responses in performance test traits with ad-libitum feeding. Animal Production 59(2): 281-291, 1994

Genetic parameter estimates of carcass traits in Charolais cattle. Journal of Animal Science 75(SUPPL 1): 149, 1997

Genetic parameters for swine carcass traits 2: Estimates of genetic and phenotypic correlations. Revista Brasileira de Zootecnia 26(1): 61-65, 1997

Genetic and phenotypic parameter estimates for reproduction traits in the Boer dam. Livestock Science 125(1): 0-65, 2009

Genetic and phenotypic analysis of meat quality traits in lamb and correlations to carcass composition. Livestock Science 143(2-3): 201-209, 2012

Analyses of published genetic parameter estimates for beef production traits. 2. Phenotypic and genetic correlations. Animal Breeding Abstracts 62(11): 825-853, 1994

Genetic and phenotypic parameter estimates for growth and conformation traits in guineafowl. Indian Journal of Animal Sciences 63(4): 445-450, 1993

Genetic and phenotypic parameter estimates for growth traits in awassi sheep. Journal of Animal Science 55(SUPPL 1): 135, 1982

Genetic and phenotypic parameter estimates for growth traits in Moghani sheep. Iranian Journal of Agricultural Sciences 29(2): 227-235, 1998

Genetic and phenotypic parameter estimates for growth traits in Boer goat. Livestock Science 124(1-3): 0-71, 2009

Phenotypic and genetic parameter estimates for reproductive traits in Zandi sheep. Tropical Animal Health and Production 45(2): 671-677, 2013

Parameter estimates for genetic effects on carcass traits of Korean native cattle. Journal of Animal Science 78(5): 1181-1190, 2000