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In the livestock industry, meat color has become important because consumer acceptance is subject to the appearance of the product in the marketplace. Our previous analyses of a whole genome QTL scan for various meat qualities using 2 [F.sub.2] families from Japanese wild boar (known as a red meat) x Large White and from Duroc x Chinese Jinhua suggested that a meat color (heine content) QTL is located on SSC6. The objective of this study was to fine-map this SSC6 meat color QTL and subsequently investigate positional candidate genes for polymorphisms that may cause changes in meat color. Therefore, we conducted interval mapping on SSC6 using an additional 9 gene markers through combined analyses of the 2 [F.sub.2] families of Japanese wild boar x Large White (353 progeny) and Duroc x Chinese Jinhua (204 progeny). Comparative analysis with humans, mice, and cattle suggested that there were 10 functional genes in the region. Among these genes, we suggested that a novel pig gene encoding a nudix (nucleoside diphosphate linked moiety X)-type motif 7 (NUDTT, a member of the nudix hydrolases) is a strong candidate for the QTL because the mouse Nudt7 is reported to hydrolyze succinyl-CoA, a substrate of the reaction limiting the rate of heme biosynthesis. We therefore determined the pig NUDT7 gene sequence including the 5' promoter region and explored genetic polymorphisms between Japanese wild boar and Large White. We identified 116 polymorphisms within the NUDT7 CDS or in the 5' region. None of the AA substitutions were associated with the meat color QTL; however, 3 polymorphisms were found in putative transcription factor recognition sites. We then investigated the differential expression of NUDT7 in Japanese wild boar and Large White by allele-specific quantitative real-time PCR. The expression level of the Large White type allele was greater than that of the Japanese wild-boar-type allele. Consequently, we speculated that the difference in meat color between Japanese wild boar and Large White is caused partly by differential expression of this candidate gene. Upregulation of NUDT7 expression in muscle may reduce succinyl-CoA content and thus reduce the level of heme biosynthesis. Key words: gene expression, meat color, meat quality, quantitative trait loci, swine doi: 10.2527/jas.2009-1814

The objective of the research was to identify QTL affecting the number of vertebrae in swine, one of the major determining factors of growth and body composition. Previously, we reported a QTL for the number of vertebrae located on SSC1qter (terminal band of the q arm of SSC 1) in an F2 family produced by crossing a Gottingen miniature male with two Meishan females. Eight other swine families were subsequently produced by crosses between different breeds of European, Asian, and miniature pigs. In these families, the QTL on SSC1qter for the number of vertebrae was detected. Unlike the Asian alleles, all European alleles in this study had the effect of increasing the number of vertebrae by 0.44 to 0.69 and acted additively without dominance. The G6ttingen miniature sire, for which we previously reported a smaller additive effect, seemed to be heterozygous at the QTL. In the present study, another QTL was found for the number of vertebrae on SSC7. This QTL was not fixed in the European pigs used as parents in our experimental families, and some of the European alleles increased the number of vertebrae. A half-sib analysis confirmed that this QTL was segregating in a commercial Large White population. Analysis in an F2 family in which the parental pigs were fixed for alternative alleles revealed that the effects of the QTL on SSC1 and on SSC7 were additive and similar in size. The two QTL acted independently without epistatic effects and explained an increase of more than two vertebrae. Key Words: Pigs, Quantitative Trait Loci, Swine, Vertebrae

Three generations of a swine family produced by crossing a Japanese wild boar and three Large White female pigs were used to map QTL for various production traits. Here we report the results of QTL analyses for skeletal muscle fiber composition and meat quality traits based on phenotypic data of 353 [F.sub.2] animals and genotypic data of 225 markers covering almost the entire pig genome for all of the [F.sub.2] animals as well as their [F.sub.1] parents and [F.sub.0] grandparents. The results of a genome scan using least squares regression interval mapping provided evidence that QTL ( Key Words: Linkage Analysis, Meat Quality, Muscle Fiber, Pigs, Quantitative Trait Loci

Contents: This study was conducted to determine suitable conditions for an experimental method in which the CRISPR/Cas9 system is introduced into in vitro‐produced porcine zygotes by electroporation. In the first experiment, when putative zygotes derived from in vitro fertilization (IVF) were electroporated by either unipolar or bipolar pulses, keeping the voltage, pulse duration and pulse number fixed at 30 V/mm, 1 msec and five repeats, respectively, the rate of blastocyst formation from zygotes electroporated by bipolar pulses decreased compared to zygotes electroporated by unipolar pulses. In the second experiment, the putative zygotes were electroporated by electroporation voltages ranging from 20 V/mm–40 V/mm with five 1‐msec unipolar pulses. The rate of cleavage and blastocyst formation of zygotes electroporated at 40 V/mm was significantly lower (p < .05) than that of zygotes electroporated at less than 30 V/mm. Moreover, the apoptotic nuclei indices of blastocysts derived from zygotes electroporated by voltages greater than 30 V/mm significantly increased compared with those from zygotes electroporated by voltages less than 25 V/mm (p < .05). When zygotes were electroporated with Cas9 mRNA and single‐guide RNA (sgRNA) targeting site in the FGF10 exon 3, the proportions of blastocysts with targeted genomic sequences were 7.7% (2/26) and 3.6% (1/28) in the embryos derived from zygotes electroporated at 25 V/mm and 30 V/mm, respectively. Our results indicate that electroporation at 25 V/mm may be an acceptable condition for introducing Cas9 mRNA and sgRNA into pig IVF zygotes under which the viability of the embryos is not significantly affected. [ABSTRACT FROM AUTHOR]

Contents Melatonin has been reported to improve the in vitro development of embryos in some species. This study was conducted to investigate the effect of melatonin supplementation during in vitro maturation ( IVM) and development culture on the development and quality of porcine embryos. In the first experiment, when the in vitro fertilized embryos were cultured with different concentrations of melatonin (0, 10, 25 and 50 ng/ml) for 8 days, the blastocyst formation rate of embryos cultured with 25 ng/ml melatonin (10.7%) was significantly increased (p < 0.05) compared to the control embryos cultured without melatonin (4.2%). The proportion of DNA-fragmented nuclei in blastocysts derived from embryos cultured with 50 ng/ml melatonin was significantly lower (p < 0.05) than that of embryos cultured without melatonin (2.1% vs 7.2%). In the second experiment, when oocytes were cultured in the maturation medium supplemented with different concentrations of melatonin (0, 10, 25 and 50 ng/ml), fertilized and then cultured with 25 ng/ml melatonin for 8 days, there were no significant differences in the rates of cleavage and blastocyst formation among the groups. However, the proportions (2.7-5.4%) of DNA-fragmented nuclei in blastocysts derived from oocytes matured with melatonin were significantly decreased (p < 0.05) compared to those (8.9%) from oocytes matured without melatonin, irrespective of the concentration of melatonin. Our results suggest that supplementation of the culture media with melatonin (25 ng/ml) during IVM and development has beneficial effects on the developmental competence and quality of porcine embryos. [ABSTRACT FROM AUTHOR]

Unlabelled: Retrograde holodiastolic flow in the abdominal aorta (retrograde flow) detected by pulsed Doppler echocardiography is usually noted in patients with aortic regurgitation or patent ductus arteriosus. Similar abnormal flow often is present in patients with acute phase Kawasaki Disease (KD). In 21 patients with acute phase KD, 15 had a retrograde flow. Retrograde flow was recognised in only 3 of patients with acute infection (n = 31) and in no healthy controls (n = 10). The ratio of the time velocity integral for diastolic retrograde flow to that for antegrade flow (regurgitant fraction) was significantly greater in patients with KD (median value 23%) than in patients with acute infection (1%) or healthy individuals (1%) (P < 0.001 for both). Four patients with coronary arterial involvement (one with an aneurysm and three with transient dilation of the coronary arteries) had a greater regurgitant fraction than the 17 patients without coronary arterial involvement (median values: 31% versus 18%, P < 0.05). The C-reactive protein was increased for a longer period of time in patients with KD with a greater regurgitant fraction (P < 0.01). Plasma nitric oxide (NO) metabolite concentrations were significantly greater in patients with KD than in those with acute infection or in healthy controls (P < 0.001 for both). There was a positive correlation between plasma NO metabolite concentrations and the regurgitant fraction in patients with KD (r = 0.69).Conclusion: Retrograde flow in the abdominal aorta is increased in patients with Kawasaki disease. Further studies are needed to clarify the causal relationship between the abnormal flow and the overproduction of nitric oxide. [ABSTRACT FROM AUTHOR]