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The objective of this study was to determine the effect of use of residual feed intake (RFI) and the blood concentration of IGF-I (IGF) as selection criteria for efficiency of gain on profitability of Japanese Black cattle selection strategies with restricted test capacity. A breeding objective that integrated the cow-calf and feedlot segments was considered. Selection strategies were defined that differed in whether information on IGF and RFI during performance testing (RFIpt) was used to make selection decisions and in the number of animals measured for IGF. In all strategies, sires were selected from the proportion chosen during the first selection stage (performance testing), modeling a 2-stage selection process. The effect on genetic gain and profitability of variations in test capacity, of the genetic correlations of IGF with marbling score (MS) and RFIpt, and nonzero economic values for and, hence, inclusion of RFI of the cow and feedlot animals in the breeding objective was examined. Additional genetic gain and profitability were generated when information on IGF concentration and RFIpt in the performance-tested young bulls was included in the selection criteria. Profit per cow was optimal when measurement of IGF and RFIpt were incorporated together in the selection index. Increasing test capacity resulted in an increase in genetic gain in all strategies, and profit per cow was optimal in all strategies when 900 places were available for performance testing. Profit per cow was more sensitive to changes in the genetic correlation between IGF and MS than between IGF and RFIpt, especially when more animals were measured for IGF, or else the favorable relationship between IGF and MS had no significant effect on profit per cow. Additional genetic gain and profitability were generated in each strategy when RFI of the cow and feedlot animals were included in the breeding objective with nonzero economic values. These results may be used to provide guidance to Japanese Black cattle breeders and, in the absence of more breed-specific information, may also have application in other Japanese beef breeds. Key words: breeding program design, carcass trait, insulin-like growth factor I, Japanese Black cattle, residual feed intake, selection strategy

The objectives of this study were 1) to examine the genetic relationship between growth and carcass traits and carcass price (CAP) and profitability in Japanese Brown cattle, 2) to estimate economic values of carcass and growth traits as regression coefficients of price and profit traits on growth and carcass traits using a multiple regression model, and 3) to compare direct and indirect predictions of the genetic merit of profit obtained from multitrait analysis and selection index, respectively. Growth and carcass traits considered in this study were ADG during the feedlot period, CWT, LM area (LMA), rib thickness (RT), subcutaneous fat thickness (SFT), and marbling score (MS). Carcass price was evaluated as a price trait independent of its influence on profit. Profit traits were defined as 1) net income per year (PROF1), 2) net income per year/energy requirement (PROF2), and 3) net income per year minus feed costs (PROF3). Correlations between direct and indirect predictions were estimated based on EBV of sires and dams with progeny records. The heritability estimate for CaP was 0.41. The heritability estimates for profit traits were high and were 0.62, 0.66, and 0.60 for PROF1, PROF2, and PROF3, respectively. The genetic correlations between CaP and ADG, CWT, LMA, RT, SFT, and MS were 0.19, 0.14, 0.30, 0.38, -0.11, and 0.98, respectively. Among the profit traits, PROF1 had the greatest genetic correlations with growth and carcass traits. The correlations with ADG, CWT, LMA, RT, SFT, and MS were 0.30, 0.21, 0.24, 0.39, -0.01, and 0.69, respectively. These estimates indicate that use of profit traits as a selection criterion may promote desirable correlated responses in growth and carcass traits. The economic values for growth and carcass traits estimated relative to CaP and each profit trait differed because of the apparent differences in the description of these traits. The correlations between EBV for the same profit traits from direct and indirect predictions were high and ranged from 0.818 to 0.846 based on EBV of sires and from 0.786 to 0.798 based on EBV of dams. The strong correlations between direct and indirect predictions for profit indicate that there is no advantage to selecting directly for profit compared with an index with all of the component traits. Key words: beef cattle, carcass trait, economic value, Japanese Brown cattle, profit

The objectives of this study were 1) to investigate the effect of changes in carcass market prices due to bovine spongiform encephalopathy (BSE) occurrences on estimates of genetic parameters and economic weights for carcass traits; and 2) to compare direct and indirect approaches for prediction of genetic merit of Japanese Black cattle for profitability of their progeny. The direct approach utilized estimated breeding values of carcass prices, whereas in the indirect approach, selection indices were constructed as products of economic weights and breeding values of component traits. Data were composed of 80,191 carcass records divided into 5 periods based on changes in carcass prices as a result of occurrences of BSE in Japan and the United States. The periods ranged from a period before occurrence of BSE in Japan to a period of beef import restrictions and a rise in prices. Carcass traits analyzed included HCW, LM area, rib thickness, subcutaneous fat thickness, and marbling score (MS). Price traits included carcass unit price and carcass sale price. Estimates of heritability for price traits were moderate (0.32 to 0.46) and slightly sensitive to changes in carcass market prices. Genetic correlations of HCW and LM area with price traits increased and that between MS and carcass sale price decreased with period, whereas estimates of genetic correlation between MS and carcass unit price were high in all periods (0.96 to 0.98). Economic weights for carcass traits varied with periods because carcass prices were highly sensitive to economic importance of traits. Nevertheless, correlations between within-period breeding values for price traits estimated using direct and indirect approaches were high (0.92 to 0.99). This result indicates that selection realized by direct and indirect approaches will provide very similar results. A comparison among within-approach breeding values estimated in different periods showed that the largest differences in breeding values of sires for price traits were between the periods after occurrences of BSE in Japan and in the United States. Economic effects of BSE occurrences influenced the importance of carcass traits and economic merits of price traits through a change of carcass prices from period to period, irrespective of the approach taken in determining the genetic merit of breeding animals for profitability of their progeny. Key words: bovine spongiform encephalopathy, carcass price, economic weight, genetic parameter

A total of 1,628 papers presented at the sixth and seventh World Congresses on Genetics Applied to Livestock Production were categorized into 20 topics according to research subjects. The aim was to determine, in relation to various topics in animal breeding and genetics, the forms of partnerships and the degree of attention given in different continents. North--North partnerships (defined as cooperation between and within developed countries) had a 68.80% representation of research papers presented, whereas North--South partnerships (cooperation between developed and developing countries) had the least representation with only 8.23% of papers. Asia contributed the most research papers in biochemical genetics, whereas Australia lead in research papers on breeding for fiber and fur. Europe contributed the most to the remaining topics, and Africa usually, but not always, contributed the least to most research topics. This study provided a useful indication of the current state of literature in animal breeding and genetics and will be useful to animal breeding and genetics researchers worldwide as they chart the way forward for research and development in the field of genetics applied to livestock production in different continents. Key words: animal breeding, developing country, genetics, livestock production, research partnership

Deterministic simulation was used to evaluate 10 breeding schemes for genetic gain and profitability and in the context of maximizing returns from investment in Japanese Black cattle breeding. A breeding objective that integrated the cow-calf and feedlot segments was considered. Ten breeding schemes that differed in the records available for use as selection criteria were defined. The schemes ranged from one that used carcass traits currently available to Japanese Black cattle breeders (Scheme 1) to one that also included linear measurements and male and female reproduction traits (Scheme 10). The latter scheme represented the highest level of performance recording. In all breeding schemes, sires were chosen from the proportion selected during the first selection stage (performance testing), modeling a two-stage selection process. The effect on genetic gain and profitability of varying test capacity and number of progeny per sire and of ultrasound scanning of live animals was examined for all breeding schemes. Breeding schemes that selected young bulls during performance testing based on additional individual traits and information on carcass traits from their relatives generated additional genetic gain and profitability. Increasing test capacity resulted in an increase in genetic gain in all schemes. Profitability was optimal in Scheme 2 (a scheme similar to Scheme 1, but selection of young bulls also was based on information on carcass traits from their relatives) to 10 when 900 to 1,000 places were available for performance testing. Similarly, as the number of progeny used in the selection of sires increased, genetic gain first increased sharply and then gradually in all schemes. Profit was optimal across all breeding schemes when sires were selected based on information from 150 to 200 progeny. Additional genetic gain and profitability were generated in each breeding scheme with ultrasound scanning of live animals for carcass traits. Ultrasound scanning of live animals was more important than the addition of any other traits in the selection criteria. These results may be used to provide guidance to Japanese Black cattle breeders. Key Words: Beef Cattle, Breeding Program Design, Breeding Schemes, Carcass Traits, Japanese Black Cattle

The importance of genotype x environment (region or management system) interactions for carcass traits in Japanese Black cattle was investigated using both univariate and multivariate animal models. The univariate approach was used mainly to test the significance of interaction effects. The multivariate approach was used to estimate genetic correlations, which indicated the magnitude of genotype x environment (GE) interactions. The more a genetic correlation deviates from 1, the larger the interaction. From the univariate approach, the addition of genotype x environment (region or management system) interaction (co)variance components resulted in an improved fit of the model for all traits in both cases (P < 0.001). However, estimates of genetic correlation between regions obtained from the multivariate approach for hot carcass weight, LM area, rib thickness, s.c. fat thickness, and marbling score were 0.97, 0.95, 0.93, 0.97, and 0.93, respectively. The corresponding estimates between management systems were 0.84, 0.92, 0.84, 0.90, and 0.97, respectively. These results indicate that GE interaction effects on carcass traits of Japanese Black cattle may be biologically unimportant. Therefore, breeding values obtained using the multivariate method would rank sires similarly in all environments. Consequently, carcass traits measured in these two different regions or management systems can be treated as the same traits. Key Words: Carcass Traits, Genotype x Environment Interaction, Japanese Black

Loci affecting coat color in an experimental cross between the Meishan breed and Dutch commercial lines are identified by scanning the porcine genome. The existence of coat color loci on chromosome 8 and chromosome 6 were confirmed.

A whole-genome scan was conducted using 132 microsatellite markers to identify chromosomal regions that have an effect on teat number. For this purpose, an experimental cross between Chinese Meishan pigs and five commercial Dutch pig lines was used. Linkage analyses were performed using interval mapping by regression under line cross models including a test for imprinting effects. The whole-genome scan revealed highly significant evidence for three quantitative trait loci (QTL) affecting teat number, of which two were imprinted. Paternally expressed (i.e., maternally imprinted) QTL were found on chromosomes 2 and 12. A Mendelian expressed QTL was found on chromosome 10. The estimated additive effects showed that, for the QTL on chromosomes 10 and 12, the Meishan allele had a positive effect on teat number, but, for the QTL on chromosome 2, the Meishan allele had a negative effect on teat number. This study shows that imprinting may play an important role in the expression of teat number. Key Words: Genome Analysis, Pigs, Quantitative Trait Loci, Teat Number