Single nucleotide polymorphisms in candidate genes are significantly associated with resistance to Haemonchus contortus infection in goats

Background: Haemonchosis is a major economic problem in goat production in humid, tropical and subtropical regions. The disease is caused by an abomasal nematode, Haemonchus contortus, which is highly pathogenic in small ruminants. The aim of this study was to identifying single-nucleotide polymorphisms(SNP) that were associated with fecal egg counts(FEC) and could be used as markers to identify resistance to H. contortus in goats.Results: Ten novel variants in the CI TA, ATP2 A3, HSPA8, STAT5 B, ESYT1, and SERPING1 genes were associated with FEC in goats with a nominal significance level of P < 0.05. Two missense mutation in the exon region of the caprine CI TA gene resulted in replacement of arginine with cysteine at position 9473550(R9473550 C) and aspartic acid with glutamic acid at position 9473870(D9473870 E). Chinese goat breeds had significantly higher FEC than Bangladeshi goat breeds within their respective genotypes. Polymorphism information content(PIC), effective al ele number(Ne), and heterozygosity(He)were greatest for the STAT5 B197A > G SNP locus in al goat breeds. Pairwise coefficients of linkage disequilibrium(D′, r2)revealed complete LD(r2= 1) between significant SNP polymorphisms in CI TA and SERPING1 and strong LD(r2= 0.93 and0.98) between polymorphisms in HSPA8 and ATP2 A3, respectively. Correlation coefficient(r) between FEC and body weight(BW) was significantly positive(r = 0.56***, P < 0.001) but that between FEC and packed cel volume(PCV) was negatively significant(r =-0.47**, P < 0.01) in the total population of goats. On the other hand, correlation coefficient(r)between BW and PCV was not significant in total population of goats. Association analysis revealed that haplotypes within ATP2 A3, HSPA8, and SERPING1 were significantly associated with FEC. Quantitative real-time PCR revealed that the relative expression of m RNA was higher(P < 0.001) for resistant, compared to susceptible, groups of goats for al candidate genes except CI TA.Conclusions: This study identified SNP markers that can potential y be used in marker-assisted selection programs to develop goat breeds that are resistant to H. contortus.

Pollution and health risk assessment of heavy metals in soils of Guizhou,China

Mining of minerals in Guizhou,China,where it is enriched with reserves,may lead to soil contamination with heavy metals.We assessed the risk of eight typical heavy metals in Guizhou soils by collecting province-wide data available in the literature and using the geo-accumulation index method,the ecological risk assessment method,and the USEPA health risk assessment model.The concentrations of eight heavy metals,except for Pb and Cr,were above the background levels.Soil heavy metal pollution evaluation results showed that As,Cu,Zn,Pb,Cr,Cd,and Ni reached the pollution levels,while Hg fell into the category of moderate contamination.As,Cu,Zn,Pb,Cr,and Ni posed low potential ecological risk,while Cd and Hg demonstrated a considerable or a very high potential ecological risk.Totally,the integrated potential ecological risk was ranked“very high”.Regarding to health risk,the non-carcinogenic risks caused by heavy metals were insignificant,but the carcinogenic risk caused by As was significant.Consequently,there appeared serious soil contamination of Hg and As,with the latter also being the greatest potential risk to human health.Both Hg and As should stay at the highest priory for remediation efforts in Guizhou soils.

青藏高原高寒草地地上生物量对气候变化的响应（英文）

Aboveground biomass in grasslands of the Qinghai-Tibet Plateau has displayed an overall increasing trend during 2003–2016, which is profoundly influenced by climate change. However, the responses of different biomes show large discrepancies, in both size and magnitude. By applying partial least squares regression, we calculated the correlation between peak aboveground biomass and mean monthly temperature and monthly total precipitation in the preceding 12 months for three different grassland types(alpine steppe, alpine meadow, and temperate steppe) on the central and eastern Qinghai-Tibet Plateau. The results showed that mean temperature in most preceding months was positively correlated with peak aboveground biomass of alpine meadow and alpine steppe, while mean temperature in the preceding October and February to June was significantly negatively correlated with peak aboveground biomass of temperate steppe. Precipitation in all months had a promoting effect on biomass of alpine meadow, but its correlations with biomass of alpine steppe and temperate steppe were inconsistent. It is worth noting that, in a warmer, wetter climate, peak aboveground biomass of alpine meadow would increase more than that of alpine steppe, while that of temperate steppe would decrease significantly, providing support for the hypothesis of conservative growth strategies by vegetation in stressed ecosystems.