No abstract

population 9. The meioses numbers submitted by each laboratory were 627, 2343, 972, 4577 and 1149, respectively. The number of marker loci submitted by each laboratory were 3, 5, 8, 23 and 10, respectively. A total of 9668 informative meioses from 30 microsatellite loci were represented in the combined data containing a total of 15 757 marker genotypes. Each data set was analysed independently using the TWOPOINT, FLIPS and CHROMPIC options. Genotypic data were then combined into a single data set using the MERGE option. The consensus linkage group was constructed using the BUILD option (LOD 3.0) followed by FLIPS5 analysis to test alternative marker orders. For the comprehensive map, markers were added using the BUILD option (LOD 1.0) again followed by FLIPS5 analysis. Markers not positioned by this criteria were added to the linkage group using the ALL option. The FLIPS5 was repeated until the best marker order was obtained. Map ®gures, number of meioses per marker (*.loc ®les), TWOPOINT and FIXED output ®les can be accessed at the http://aipl. arsusda.gov/maps. Consensus map: Twelve markers typed by more than one laboratory were used to produce a sex-average consensus map spanning 69.9 cM (Fig. 1). The female map was 63.8 cM in length and the male map was 71.8 cM (data not shown). Comprehensive map: Marker genotypes from 30 loci were analysed to produce a comprehensive map of BTA25 (Fig. 1). The length of the sex-averaged was 73.3 cM (Fig. 1), while the female and male maps were 64.0 and 75.4 cM, respectively (Data not shown). The average interval was 2.44 cM, and the largest intermarker interval of 8.4 cM was found between RM134 and ETH153. The order producing the highest loglikelihood is presented.

The report of the bovine chromosome 4 (BTA4) workshop is presented. Six laboratories contributed a total of 30,168 informative meioses from 62 loci. Twenty-two loci were typed by at least two independent laboratories and were used to construct a consensus linkage map of BTA4. The remaining 40 loci were subsequently incorporated into a comprehensive map. The sex-averaged consensus map covered 131.4 cM. The female map was 124.3 cM in length, while the male map was 134.3 cM. The comprehensive sex-averaged map spanned 141.6 cM. The length of the female and male comprehensive maps were 123.1 cM and 156.4 cM, respectively. Average genetic distance between loci was 6 and 2.3 cM for the consensus and comprehensive linkage maps, respectively.