Genome-wide association analysis reveals genomic regions on Chromosome 13 affecting litter size and candidate genes for uterine horn length in Erhualian pigs.

Litter size has a great impact on the profit of swine producers. Uterine development is an important determinant of reproduction efficiency and could hence affect litter size. Chinese Erhualian pig is one of the most prolific breeds in the world, even though large phenotypic variation in litter size was observed within Erhualian sows. To dissect the genetic basis of the phenotypic variation, we herein conducted genome-wide association studies for total number born and number born alive (NBA) of Erhualian sows. In total, one significant single nucleotide polymorphism (SNP) (P<1.78e-06) and 11 suggestive SNPs (P<3.57e-05) were identified on 10 chromosomes, confirming seven previously reported quantitative trait loci (QTL) and uncovering six QTL for litter size or uterus length. One locus on Sus scrofa chromosome (SSC) 13 (79.28 to 90.43 Mb) harbored a cluster of suggestive SNPs associated with multiparous NBA. The SNP (rs81447100) within this region was confirmed to be significantly (P<0.05) associated with litter size in Erhualian (n=313), Sutai (n=173) and Yorkshire (n=488) populations. Retinol binding protein 2 and retinol binding protein 1 functionally related to the development of uterus were located in a region of 2 Mb around rs81447100. Moreover, four genes related to embryo implantation and development were also detected around other significant SNPs. Taken together, our findings provide a potential marker (rs81447100) for the genetic improvement of litter size not only in Chinese Erhualian pigs but also in European commercial pig breeds like Yorkshire, and would facilitate the final identification of causative variant(s) underlying the effect of SSC13 QTL on litter size.

Identification of new single nucleotide polymorphisms affecting total number born and candidate genes related to ovulation rate in Chinese Erhualian pigs.

The Chinese Erhualian pig has the highest record for litter size in the world. However, the genetic mechanism of its high prolificacy remains poorly understood. In our study, large phenotypic variations in litter size were found among Erhualian sows. Significant differences in total number born (TNB) and corpora lutea numbers were observed between sows with high and low estimated breeding values (EBVs) for TNB. To identify single nucleotide polymorphisms (SNPs) associated with TNB, a selective genomic scan was conducted on 18 sows representing the top 10% and 18 sows representing the bottom 10% of EBVs of 177 sows using Illumina Porcine SNP60 genotype data. Genome-wide fixation coefficient (FST ) values were calculated for each SNP between the high- and low-EBV groups. A total of 154 SNPs were significantly differentiated loci between the two groups. Of the top 10 highest FST SNPs, rs81399474, rs81400131 and rs81405013 on SSC8 and rs81434499 and rs81434489 on SSC 12 corresponded to previously reported QTL for litter size. The other five SNPs, rs81367039 on SSC2, rs80891106 on SSC7, rs81477883 on SSC12 and rs80938898 and rs80971725 on SSC14, appeared to be novel QTL for TNB. Significant associations between rs81399474 on SSC8 and TNB were confirmed in 313 Erhualian sows. Forty genes were identified around the top 10 highest FST SNPs, of which UCHL1, adjacent to rs81399474, and RPS6KB1 and CLTC, adjacent to rs81434499, have been reported to affect the ovulation rate in pig. The findings can advance understanding of the genetic variations in litter size of pigs.

[The thickness change and clinical significance of tunica intima and smooth muscle in artery after hydrolic dilation].

OBJECTIVE: To study the proliferation change of tunica intima and smooth muscle in artery after hydrolic dilation for potential clinical use. METHODS: Sixten adult New Zealand rabbits were randomly divided into 4 groups, named group A, B, C and D. Right carotid arteries of rabbits of those 4 groups were dilated by hydrolic dilation with different pressures with 0 kPa, 40 kPa, 80 kPa, and 120 kPa respectively. The arterial calibers, thickness of tunica intima and smooth muscle were analyzed by automatic medical photograph analyzer immediately, 1 week and 2 weeks later respectively. RESULTS: The arterial calibers in the experimental group were larger than those in control group after immediate hydrolic dilation and 1 week later (P < 0.01). At 2 weeks, the arterial calibers in group B and D has no significant difference compared to group A (P > 0.05), and those in group C were larger than that of group A (P < 0.01). There were no significant difference in thickness of tunica intima and smooth muscle between the experimental group and control group (P > 0.05) after immediate hydrolic dilation. At 1 and 2 weeks after dilation, there were no significant difference between group A and group B (P > 0.05), and those in group C and D were all larger than those in group A (P < 0.01). No obvious proliferation of tunica intima were observed in group B at 2 weeks after hydrolic dialation, but the proliferation of tunica intima could be observed in group C and D, especially in group D. CONCLUSION: Caliber of artery can be expanded by hydrolic dilation with higher pressure, but the proliferation of tunica intima and smooth muscle may be occurred in hydrolic dilation with higher pressure over 80 kPa, therefore it is safe to use hydrolic dilation with pressure no more than 40 kPa.

Thumb reconstruction in a bilateral upper extremity amputee: an alternative to the Krukenburg procedure.

A 23-year-old man sustained traumatic loss of both hands. His left defective forearm underwent lengthening with a 3-cm segment of the ipsilateral radius; this was immediately followed by an ipsilateral second toe microvascular transfer to the stump of the radius to provide pinch. Two years after the procedure the reconstructed hand had recovery of both motion and sensibility.