No abstract

Single nucleotide polymorphisms in the coding sequence of melanoeortin-4 receptor (MC4R) gene were detected by PCR-SSCP and DNA sequencing method in Harbin white rabbit, Tianfu black rabbit, Belgian hare, ZIKA rabbit, and California rabbit breeds. A-->G conversion mutation at base position 237 was found with high frequency in Harbin white rabbit, Belgian hare, and Zika rabbit and low frequency in Tianfu black rabbit and California rabbit. The allele A was pre-dominant allele for each of meat rabbit breeds. AA genotype frequency was higher than AG genotype in the five studied rabbit breeds. GLM analysis for the effect of genotypes on performance traits demonstrated that AG genotype was significantly associated with body weight, eviscerated weight and feed conversion efficiency (P<0.05), but not significantly associated with cooking loss (P>0.05). It was concluded from the results that MC4R gene could be a candidate modifier gene that affects or controls body weight and carcass traits of rabbit.

The NLRP12 (NLR family, pyrin domain containing 12) serves as a suppressor factor in the inflammatory response and protects the host against inflammation-induced damage. In the present study, we aimed to study the polymorphisms of NLRP12 gene and its association with susceptibility to non-specific digestive disorder (NSDD) in rabbits. We re-sequenced the entire coding region of the rabbit NLRP12 gene and detected a total of 19 SNPs containing 14 synonymous and five non-synonymous variations. Among them, the coding SNP (c.1682A>G), which would carry a potential functional implication, was subsequently subjected to genotyping for case-control association study (272 cases and 267 controls). The results revealed that allele A was significantly protective against NSDD with an odds ratio value of 0.884 (95% confidence interval, 0.788 to 0.993; p = 0.038). We also experimentally induced NSDD in growing rabbits by feeding a fibre-deficient diet and subsequently investigated NLRP12 mRNA expression. The mRNA expression of NLRP12 in healthy status was significantly higher than that in severe NSDD (p = 0.0016). The highest expression was observed in individuals carrying the protective genotype AA (p = 0.0108). These results suggested that NLRP12 was significantly associated with the NSDD in rabbits. However, the precise molecular mechanism of NLRP12 involving in the development of rabbit NSDD requires further research.

Five rabbit populations (Belgian hare, Tianfu black rabbit, Great line of Zika rabbit, Harbin white rabbit, and California rabbit) were used to analyze the polymorphism of growth hormone receptor (GHR) gene by PCR-SSCP. Results indicated that there were two mutation sites (C705T and C810T) in the 5 populations. The least square analyses showed that the live weight, visceraste weight, and slaughter percentage of AA and MM genotypes were significantly lower than BB and NN genotypes (P<0.05). In contrast, the GHR polymorphism had no significant difference for least squares means of feed transformation efficiency (P>0.05). It suggested that GHR gene may be a candidate gene responsible for butcher trait in rabbit.

Electronic transformer (ET) is wildly used in digital smart substation. However, the actual running time of ETs is generally short, and most of them have higher failure rate than that of traditional transformers. Since the accuracy and stability of ETs data collection affect the safe operation of smart grid, it is necessary to study the fault diagnosis method of ETs. According to the characteristics of ETs, this paper proposes an on-line fault diagnosis method of ET based on wavelet transform theory. After noise reduction the output signal waveform of the transformer, the high frequency decomposition coefficient is obtained by wavelet transform, so as to diagnose and locate the three kinds of faults: drift deviation fault, variable ratio deviation fault, and fixed deviation fault.