Summary Linkage maps of Sus scrofa chromosome 4 (SSC4) based on 19 markers were similar in lengths for three F2‐families [Wild Boar (W), Meishan (M) and Pietrain (P) crosses] and in agreement with the previously published maps. Quantitative trait loci (QTLs) on SSC4 affect mainly muscle and fat mass. Compared with others, Pietrain alleles were associated with longer carcass, higher body weight and higher meat content. In all three families, the profiles of F ratio values for these traits showed peaks close to the positions of candidate genes V‐ATPase, ATP1A2 and ATP1B1. Additional more proximally mapped QTLs, significant at the p < 0.05 chromosome‐wide level, were found in the M × P and W × P families. The W × M family revealed highly significant QTLs located in the vicinity of AMPD1 and NGFB. The SSC4 QTLs explained up to 12% of F2 phenotypic variance.
Summary Linkage maps have been constructed for Sus scrofa chromosome 6 (SSC6) based on 17 markers, of which 10 were used in all three F2 families of Wild Boar (W), Meishan (M) and Pietrain (P) crosses. The coverage of the linkage maps of SSC6 was almost complete. All loci were ordered identically in the families, but two intervals (RYR1‐A1BG‐EAH, S0146‐S0003‐SW824) differed from published maps. Major quantitative trait loci (QTLs) for meat quality, stress resistance and carcass composition explaining up to 59% of F2 phenotypic variance have been mapped in the M × P and W × P families centred on the segregating RYR1 T and C alleles. In the W × M family, which was homozygous for the RYR1 C allele, no QTL effects for meat quality and stress‐resistance, but moderate effects for carcass composition have been observed in this region. These findings indicate further loci closely linked with the RYR1 or/and further alleles at the RYR1 locus, involved in the variation of carcass and growth traits.
Summary Linkage maps of Sus scrofa chromosome 7 (SSC7) for three informative F2 families, based on Wild Boar (W), Meishan (M) and Pietrain (P) crosses, were constructed using 16 marker loci. Maps were consistent for the families, except the order of the markers PI2‐PO1A‐S0212 in the W × M family which was inverted in the M × P and W × P families. Important quantitative trait loci (QTLs) were localized in the region of the SLA complex in the M × P and W × M families. These explained up to 16% of F2 phenotypic variance for body conformation, fat deposition and muscling. In the W × P family, minor QTLs were mapped outside the SLA region. The highly significant QTL alleles were mainly additive (a > d). The Meishan alleles for QTL located in the SLA region were associated with higher head weights and carcass lengths, but with lower carcass fat contents than those from Wild Boar and Pietrain. The cryptic Meishan QTL allele, which reduces carcass fat, provides one of the first examples of transgressive segregation in animals and emphasizes that useful genetic variation can be hidden in the genetic background of a breed.
Summary Linkage maps of Sus scrofa chromosome 1 (SSC1) have been produced using 10 markers in three different F2 families based on crosses of Meishan (M), Pietrain (P) and Wild Boar (W). The maps were similar for the different families and show higher paternal recombination, especially in the interval SW2130–SW803. Quantitative trait loci (QTLs) affecting body conformation, carcass composition, fat deposition and numbers of teats were identified in all three families. Major QTLs were mapped in chromosomal intervals centred at approximately 60, 120 and 170 cM. The QTLs explain up to 8.4% of phenotypic variance in the F2 generation. Pietrain QTL alleles were superior in comparison with Wild Boar and Meishan alleles for most of the trait values. Meishan alleles were associated with highest fat deposition. Additive gene effects were generally larger than dominance effects. QTL profiles on SSC1 differed between families, with the W × P family being most distinct.
By means of quantitative studies of the J activity of bovine intact erythrocytes and of erythrocyte lipids it is concluded that all of the J activity of J-containing cells is due t o a lipid and that all J substance is present on the erythrocyte surface and thus available for J antibody. No J substance seems to be buried in the depth of the membrane.During the process of hemolysis and subsequent washings bovine erythrocytes release a considerable portion of their membrane constituents in a "soluble" form. I n order to prevent a disruption of ghosts a small amount of MgCl, must be added to the hemolyzing mixture. We observed a loss of more than 30°/, of the original J activity along with about 150/, of various stroma constituents unless MgCl, had been added to the hemolyzing mixture.By treatment of bovine stroma (prepared in the presence of added MgC1,) with organic solvents of increasing polarity two lipid fractions, "loosely" and "strongly" bound lipids, can be obtained. The J activity was found only in the "strongly" bound fraction along with the majority of glycolipids.By treatment of bovine J-cell ghosts with hypertonic saline part of the stroma constituents, including the J substance, is solubilized. It is concluded that the J substance, though secondarily absorbed from the serum onto the erythrocyte surface, is fully integrated to the other membrane constituents.The bovine J blood-group substance is primarily dissolved in the blood plasma [l] and is absorbed from there onto the erythrocytes during a postnatal period. Previous reports from these laboratories [2]have shown that the J substance of serum is a lipoprotein and that its determinant is a glycosphingolipid. The goal of further studies has been to investigate how the J substance is attcahed to the erythrocyte membrane. This paper described the &st results of such investigations. Some of the following results have already been presented at the XIIthInternational Conference on Animal Blood Groups (Budapest, July 1970). MATERIALS AND METHODSBlood was drawn from cattle which were classed as being with or without the J substance. As the anticoagulant one part by volume of a solution containing 2 0 g sodium citrate and 5 g sodium chloride per 1000 ml water was used for 4 parts of blood.I n order to obtain erythrocytes containing J substance for the hemolysis-inhibition tests one part by volume ofa solution containing 32 g sodium citrate,Enzyme. Acetylcholinesterase (EC 3.1.1.7). 10 g glucose, 5 g sulfanilamide, 0.04 g RivanolQ and 0.2g sodium cyanide per 1000ml water was used for about 4 parts of blood. This mixture was stored a t 4 "C for up to 6 weeks. From this mixture small samples of erythrocyte suspensions were freshly prepared by centrifugation and sufficient washing with an excess of isotonic (0.15M) saline a t room temperature.Serum was obtained from freshly drawn blood by allowing it to stand a t room temperature overnight.For serological tests anti-J serum was used which had been checked in international comparison tests. I n addition, an anti...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.