Association analysis between variants in bovine progesterone receptor gene and superovulation traits in Chinese Holstein cows

The objective of this study was to identify a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism. The PCR-RFLP method was applied to detect two reported single nucleotide polymorphisms (SNPs) of G59752C and T81637C (rs41614030) located in introns 3 and 4 of the bovine progesterone receptor (PGR) gene in 171 Chinese Holstein cows treated for superovulation and evaluate its associations with superovulation traits. In polymorphic locus 81637, all cows without superovulation response were g.81637TC and g.81637TT genotypes. Association analysis showed that these two SNPs had significant effects on the total number of ova (TNO) (p<0.05), and the T81637C polymorphism was significantly associated with the number of transferable embryos (p<0.05). In addition, significant additive effects (p<0.05) on TNO were detected in the polymorphisms of G59752C and T81637C. These results showed for the first time that the G59752C and T81637C polymorphisms in PGR gene were associated with superovulation traits and indicated that PGR gene can be used as a predictor for superovulation in Chinese Holstein cows.

An MspI polymorphism in the inhibin alpha gene and its associations with superovulation traits in Chinese Holstein cows

To identify a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism, the PCR-RFLP method was applied to detect an A>G transition determining an MspI polymorphism at position 192 in the exon I of the bovine inhibin alpha (INHA) gene and evaluate its associations with superovulatory response in 118 Chinese Holstein cows treated for superovulation. Association analysis showed that cows with the GG genotype resulted in a significant increase in the number of ova (TNO) than AG and AA genotypes in the first (P=0.023), second (P=0.004) and third (P=0.002) superovulation treatments and produced more transferable embryos (NTE) than that of AG and AA genotypes in the third (P=0.045) superovulation treatment. Moreover, individuals with GG genotype produced more transferable embryos than AA (P<0.05) genotype in the second superovulation treatment and all cows without superovulation response were mutations with genotypes of AA and AG. These results indicate that INHA gene can be used as a predictor for superovulation in Chinese Holstein cows, and imply that cows with AA genotype should be excluded for superovulation practices.

Polymorphisms in the 5' upstream region of the FSH receptor gene, and their association with superovulation traits in Chinese Holstein cows

To identify a predictor to forecast superovulation response on the basis of associations between superovulation performance and gene polymorphism, variation in the bovine follicle stimulating hormone receptor (FSHR) gene was investigated using PCR-single-strand conformational (PCR-SSCP) and DNA sequencing. One single nucleotide polymorphism (SNP) of G-278A located in the 5' upstream region of bovine FSHR gene was found in 118 Chinese Holstein cows treated for superovulation. Two SNPs of G-278A (GU253337) and A-320T (rs43676359) were analyzed. In polymorphic locus -278, all cows without superovulation response were mutations with genotypes of CD and DD. Cows with CC genotype had a significant increase in the total number of ova (TNO) (P<0.01), and produced more transferable embryos (NTE) than those of the CD and DD genotypes (P<0.01). At this locus, the additive effects seemed to be highly significant (P<0.01) and allele C was associated with an increase in the TNO and NTE. These results indicated that the FSHR is a potential marker for superovulation response and can be used as a predictor for superovulation in Chinese Holstein cows.

[Relationship between genetic diversity of chromosome 6 determined by microsatellite markers and litter size in Hu sheep]

Genetic diversity and relationship with litter size were analyzed in Hu sheep using 6 microsatellite markers LSCV043, BMS2508, GC101, 300U, Bulge5, and 471U, which were closely linked to FecB gene. Thirty-four alleles and 53 genotypes were detected at 6 microsatellite loci, which were all polymorphic. Three markers LSCV043, BMS2508 and 300 U were highly polymorphic loci. The polymorphism information content (PIC) were 0.6674, 0.6035, and 0.5615, respectively. The total mean of litter size of genotype LSCV043 107 bp/123 bp was significantly higher than that of genotype 110 bp/123 bp. The litter size of the first lambing for genotypes BMS2508 154 bp/154 bp, 154 bp/170 bp and 154 bp/200 bp were significantly higher than that of genotype 170 bp/170 bp (P<0.05). Furthermore, total litter size for BMS2508 170 bp/170 bp was the lowest in all the genotypes within this locus (P<0.05). No significant difference was detected in other genotypes.

Polymorphism of FecB gene in nine sheep breeds or strains and its effects on litter size, lamb growth and development

Nine sheep breeds or strains, including 615 individuals were screened with forced PCR RFLP method for the FecB gene to study the polymorphism and its effects on litter size, body weight and body size. Results showed that the polymorphism frequencies of FecB gene were significantly imbalanced in these breeds or strains. The Hu sheep were all homozygous carriers of FecB gene(BB). In the Chinese Merino prolific meat strain, the genotype frequencies of BB, B+ and ++ were 51%, 30% and 19%, respectively, whereas all the other flocks had only the wild-type (++) genotype. Results within the Chinese Merino prolific meat strain showed that the mean litter size of ewes with genotype BB and B+ were 2.8 (+/-0.74) and 2.3 (+/- 0.63) (P < 0.05), whereas ++ genotype ewes had a litter size of only 1.2 (+/-0.68) (P < 0.01). At day 90 after birth, the body weights of BB/B+ genotype lambs were higher than that of ++ genotype lambs (18.6 +/- 3.70 kg, 18.0 +/- 3.71 kg vs 15.6 +/- 2.22 kg, P < 0.05). In addition, the heart girth and chest width of BB/B+ genotype lambs were significantly longer than those of the ++ lambs (P < 0.05). No significant differences were observed in either body weight or body size at day 120. Litter size at first lambing from Hu at Natural Source Conservative Region was found to be significantly higher than that from the other two regions sampled (P < 0.05). In addition to the additive effect on litter size, these findings showed for the first time that the FecB gene had a positive effect on early postnatal body growth.

[Research progress on genetic diversity of sheep PRNP and resistance breeding]

Prion protein (PrP) is a pathogeny identified in recent years, which infects both mankind and other mammals. It has been proved that PrP is a sole protein able to duplicate and propagate with itself. PrP can express in many tissues and has important physiological functions in many species of animals. The conformation change of PrP is the origin of transmissible spongiform encephalopathies (TSEs). It has been proved that the sheep genetic diversity of prion protein gene (PRNP) is significantly associated with the resistance to scrapie. In this review, the evidence of association between polymorphisms of PRNP and resistance or susceptibility to scrapie and its effects on reproduction and performance traits were focused. The aim is to provide theory guidance for sheep breeding resistant to disease.

Polymorphism of the growth hormone gene and its association with growth traits in Boer goat bucks

In the present study, the polymorphism of growth hormone (GH) gene was analyzed as a genetic marker candidate for growth traits in Boer goat bucks. Two single nucleotide polymorphisms (SNPs) - A781G (Ser/Gly35) and A1575G (Leu147), were identified by GH gene sequencing and PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) analysis. AA genotype resulted in a significant decrease in birth chest girth (P=0.03) and weaning weight (P=0.014) comparing to AB genotype, while CC genotype contributed to weaning height (P=0.04) greater than CD genotype. When in combination, AACD genotype was undesired for lower scores in a series of growth traits including body weight, length, height, and chest girth at birth and weaning, as well as the pre-weaning daily gain and body weight at age of 11 months. These results indicate that new molecular markers associated with caprine growth traits can be used in MAS (marker-assisted selection) in Boer goat bucks.

1H and 13C NMR assignments for 6-demethylvermistatin and two penicillide derivatives from the mangrove fungus Guignardia sp. (No. 4382) from the South China Sea

One new compound 6-demethylvermistatin (1), together with two known compounds, the penicillide derivatives (2) and (3) were isolated from the mangrove fungus Guignardia sp. No. 4382 obtained from the South China Sea. Their structures were assigned using high-resolution electron ionization mass spectrometry(HREIMS), (1)H and (13)C NMR spectra, DEPT, and by 2D COSY, HMQC, and HMBC experiments. The absolute configuration of 1 was established by comparison of its CD with that of vermistatin.

Identification of mutations of zona pellucida glycoprotein (ZP3) and its association with pig reproductive traits

Reproduction is a complex trait, controlled by genetic and environmental factors. Genetic improvement of this trait is important for animal breeders to improve the animal's production efficiency. Apart from genetic factors, animal production can be affected by environmental factors, i.e. the nursing ability of the sow, which is in turn affected directly by effective teat number (teats producing milk normally, TN) and number of piglets born alive (NBA). The objective of this study was to find new mutations, such as single nucleotide polymorphisms (SNPs) from the Zona Pellucida glycoprotein gene (ZP3) using Single Strand Chain Polymorphism (SSCP) and nucleotide sequencing and to investigate association between genetic variations and sow reproductive traits. We identified 13 new SNPs from exon 1, two new SNPs from intron 2, one SNP from intron 6 and a 18 bp (GCACGTGGTCCTCCTGG)-deletion/insertion from intron 2 of the ZP3 gene. Five out of these mutations were selected to genotype in five different breeds (Small Meishan, Qingping, Duroc, Landrace and Large White) and association with reproductive traits in European breeds (Duroc, Landrace and Large White). The sows with genotype AA had more 1.11 piglets NBA than of the sows with genotype AB (p < 0.05) in the 18 bp deletion/insertion of intron 2, while non-significant associations between the other mutations and reproductive traits (NBA and TN) were found.

HaeⅡ RFLP of INHA and its relationship to goat litter size

The polymorphism in a fragment within the coding region of the inhibin a subunit ( INHA ) gene was studied in 323 heads of Matou, Nubi, Boar and Haimen goats by PCR-SSCP, PCR-RFLP and sequencing. A new mutation G284A (Accession number: L28815) was identified, which could be detected by Hae digestion of a PCR product spanning this site. Hae PCR-RFLP analysis indicated that allele G was dominant. Association studies indicated that the effect of INHA genotypes on litter size was greatest for GG, followed by AG and AA genotypes. Thus, INHA may be a major gene controlling the prolificacy of goat, and allele G is positively correlated with litter size.

[Association between the canine monoamine oxidase B (MAOB) gene polymorphisms and behavior of puppies in open-field test]

Excitability, activity and exploration behavior of puppies in a novel open-field were tested in a total of 204 two-month-old German shepherd dog, labrador retriever or English springer spaniel puppies. The polymorphisms of monoamine oxidase B gene (MAOB) were detected by PCR-RFLP. Statistics analysis indicated that genotype and allele frequencies of the polymorphisms were significantly different among three breeds (P < 0.01). With GLM analysis of SAS software, association analysis was conducted between MAOB gene polymorphisms and locomotion and vocalization behavior parameters in the open-field test. The results showed that MAOB gene polymorphisms had a significant effect on walking time, squares crossed, lying time, the times of standing up against walls(P < 0.01 or P < 0.05) and were associated with the times of posture change (P=0.064). Walking time and squares crossed were higher in TT genotype puppies than those in TC and CC puppies (P < 0.05) and the times of posture change and standing up against walls were also higher than those in CC (P < 0.05). In addition, lying time in CC genotype puppies were higher than that in TT (P < 0.05). MAOB had a positive effect on walking time, lying time, squares crossed, the times of posture change, the times of standing up against walls in the three dog breeds that was highly statistically significant (P < 0.01 or P < 0.05). Our results imply that MAOB gene significantly affects the excitability, activity and exploration behavior of puppies in open-field test and TT genotype has favorable effects in these behavior traits.

[Polymorphism analysis of genes associated with hindquarters muscular development on chromosome 18 in Xinjiang meat sheep]

Through polymorphism analysis of genes associated with hindquarters development on chromosome 18 in Xinjiang meat sheep, we sought genes that are associated with increased hindquarters musculature in the hope to provide theoretical guidance to molecular marker-assisted selection of meat sheep. The polymorphism of Callipyge (CLPG) gene was analyzed by PCR-SSCP and PCR-RFLP in populations of Dorset and Suffolk breeds and their F1 and F2 crosses with local Xinjiang Fine Wool sheep. Results showed that there was no PCR-RFLP polymorphism at 103849 bp in the region between DLK1 and GTL2 on chromosome 18, which suggested that hindquarters over-development was not controlled by the callipyge gene (CLPG) in Xinjiang meat sheep group. In addition, single nucleotide polymorphisms (SNPs) were detected at the Meg3.9 locus on chromosome 18 by PCR-SSCP. Based on the polymorphism, three genotypes AA, AB and AC could be discerned in this locus, with AA being the major one. The relationship between the genotypes and hindquarters hypertrophy was also investigated in the same group. Results indicated that the AC genotype had a significant impact on the hindquarters hypertrophy while the other two were not related to the muscling trait. In F1 crosses between Dorset and local fine wool sheep breeds, there was a significant difference in carcass weight and slaughter rate between the AC genotype and the other two genotypes (P<0.05), but there was not significant difference in the monthly live weight among the three genotypes (P<0.05). Based on the above, we found the muscling trait did not result from the mutation in at the 9571-268.3 site of the CLPG locus. Thus it may be under the influence of other genes or multiple linked QTL.

Polymorphism of FecB gene in nine sheep breeds or strains and its effects on litter size, lamb growth and development

Nine sheep breeds or strains, including 615 individuals were screened with forced PCR RFLP method for the FecB gene to study the polymorphism and its effects on litter sizes, body weights and body sizes. Results show that the polymorphism frequencies of FecB gene are significantly imbalanced in these breeds or strains. The Hu sheep were all homozygous carriers (BB). In the Chinese Merino prolific meat strain, the genotype frequencies of BB, B+ and ++ are 51%, 30% and 19%, respectively, whereas all the other flocks had only the wild-type (++) genotype. Results within Chinese Merino prolific meat strain showed that mean litter sizes of ewes with genotype BB and B+ are 2.8 (+/-0.74) and 2.3 (+/-0.63) (P > 0.05), whereas ++ ewes had a litter size of only 1.2 (+/-0.68) (P < 0.01). At 90 days after birth, the body weights of BB/B+ lambs were higher than that of ++ lambs (18.6 +/- 3.70 kg, 18.0 +/- 3.71 kg versus 15.6 +/- 2.22 kg, P < 0.05). In addition, the heart girth and chest width of BB/B+ lambs were significantly longer than ++ lambs (P < 0.05). No significant differences were observed in either body weight or body size at day 120. Litter size at first lambing from Hu at Natural Source Conservative Region was found to be significantly higher than that from the other two regions sampled (P < 0.05). In addition to the additive effect on litter size, these findings show for the first time that the FecB gene had a positive effect on early postnatal body growth.

[Development of a rapid mismatch PCR method using tetra-primer ARMS for detection of BMPR-IB gene mutation in sheep]

Tetra-primer ARMS PCR is a rapid, simple and efficient method for the detection of single nucleotide polymorphism (SNP). Bone morphogenetic protein receptor IB (BMPR-IB) gene is a major effect gene that controls prolific trait in Booroola Merino sheep. The aim of this study was to establish a tetra-primer ARMS PCR method for the detection of BMPR-IB genotype. Specific primers around the mutation locus (A746G) were designed according to the principle of tetra-primer amplification refractory mutation system PCR. Furthermore, a pair of primers were designed to amplify the DNA fragment, which contain the mutation locus as positive control, and an individual genotype was directly detected by one round of PCR amplification. The detection efficiency of sheep BMPR-IB genotyping was greatly improved by use of this method.

[The polymorphism distributions of six STR loci in dairy cattle and beef cattle]

The polymorphism distributions of six STR loci, BM2113, BM1862, BMc701, BM2934, TGLA122,and BM720 were detected in cattle by Polymerase Chain Reaction and multiplex gel electrophoresis followed by silver staining. Gene frequency (P(i)),power of discrimination (DP), heterozygosity (H), polymorphism information content (PIC) and probability of paternity exclusion (PE) were calculated. All loci obey Hardy-Weinberg equilibrium. DP, H and PIC of BM2113 locus, and PE of TGLA122 locus are the biggest among six STR loci in Holstein Friesian. Cumulate DP of six STR loci is 0.99997, Cumulate PE of six STR loci is 0.98827. DP, H, PIC and PE of BM1862 loci are the biggest among six STR loci in beef. Cumulate DP of six STR loci is 0.99999, Cumulate PE of six STR loci is 0.99578. These results showed that the six STR loci could be used as linkage analysis, individual identification and paternity test in cattle.

Antimicrobial susceptibility of Neisseria gonorrhoeae strains isolated in Guangzhou, China, 1996-2001

OBJECTIVE

To investigate the in vitro antimicrobial susceptibility and resistant trends of Neisseria gonorrhoeae strains isolated in Guangzhou, from 1996 to 2001.

METHODS

The agar dilution method was used to determine the minimum inhibitory concentrations (MICs) to four antimicrobials, penicillin G, ciprofloxacin, ceftriaxone, and spectinomycin. The resistance of all strains to four antibiotics was interpreted according to criteria used in the project of surveillance of gonococcal antibiotic susceptibility in the WHO Western Pacific Region. Penicillinase producing N gonorrhoeae (PPNG) was analysed by the paper acidometric method.

RESULTS

793 consecutive N gonorrhoeae isolates collected in Guangzhou were studied from 1996 to 2001. A total of 55 strains of PPNG were identified and the prevalence rapidly spread from 2% to 21.8%. Of the four antibiotics examined, ceftriaxone and spectinomycin appeared to be the most effective agents although two spectinomycin resistant strains were isolated in 1996. Their MIC(50), MIC(90), and geometric mean MIC (MICmean) were all between the sensitive ranges of the interpretative criteria and remained stable over the years. However, resistance increased continuously to penicillin G and dramatically to ciprofloxacin. In 1996-2001, MIC(50), MIC(90), and MICmean of penicillin G increased from 1 micro g/ml to 2 micro g/ml, 4 micro g/ml to 32 micro g/ml, and 0.68 micro g/ml to 2.35 micro g/ml, respectively; those of ciprofloxacin steeply increased from 0.12 micro g/ml to 4 micro g/ml, 2 micro g/ml to 32 micro g/ml, and 0.14 micro g/ml to 2.62 micro g/ml in 1996-9, respectively, and then declined slightly in 2000-1. The prevalence of resistant isolates spread from 57.2% to 81.8% for penicillin G and from 17.6% to 72.7% for ciprofloxacin over the 6 years.

CONCLUSION

Resistance to penicillin and ciprofloxacin increased greatly during 1996-2001. Ceftriaxone and spectinomycin should be used as the first line agents in treating gonorrhoea. It is of great importance to continuously survey the susceptibilities of N gonorrhoeae to antibiotics in controlling the spread of gonococcal infections.

[Anatomical study and clinical application of medial femoral condylar bone flap pedicled with the saphenous vessels]

OBJECTIVE

To investigate a new operative method for repairing nonunion and defect of tibia.

METHODS

First, observe the relation between the joint branches of descending genicular artery and the saphenous branch of descending genicular artery in 10 cadevers. Then the medial femoral condylar bone flap pedicled with the saphenous vessels was prepared in 4 cadavers for simulated purpose. Clinically, two patients with tibial nonunion were treated by transplantation of this pedicled bone flap.

RESULTS

In the 4 simulated operations, the ink which was injected into the femoral artery could be released from the joint branches. And in the clinical operation, the area of the pedicled bone flaps were 5.0 cm x 2.0 cm x 1.5 cm and 4.5 cm x 1.5 cm x 1.5 cm respectively. Followed up for 8 to 12 weeks, the fracture unioned well.

CONCLUSION

This operation is simple and reliable, it is characterised by 1. unnecessary to anastomosis the vessels 2. reliable blood supply 3. high quality of bone flap 4. either bone flap or bone-skin flap can be chosen 5. long vessel pedicle.