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991.
992.
Plastic hematocrit tubes (PHTs) are convenient tools for electron microscopy (EM) of peripheral blood buffy coats, and the PHT‐EM technique is expected to be a practical method for veterinary clinical medicine. In this study, fixatives composed of various concentrations of sucrose, glutaraldehyde, and phosphate buffer (PB) were tested for preparing canine and feline buffy coats. The highest quality images were obtained using a fixative consisting of 2.5% glutaraldehyde in 0.1 m PB, and it was concluded that this method allows clinicians who are inexperienced in histological techniques can conveniently transport buffy coat samples to diagnostic laboratories for analysis by EM.  相似文献   
993.
In stallions, impaired acrosome reaction (IAR) may often cause subfertility. Single nucleotide polymorphisms (SNPs) within FK506‐binding protein (FKBP6) seem to be associated with IAR in stallions. However, their effect on stallion fertility has not yet been quantified. Using whole‐genome sequence data of seven stallions, we searched FKBP6 for mutations to perform an association study in Hanoverian stallions with estimated breeding values for the paternal component of the pregnancy rate per oestrus cycle (EBV‐PAT) as target trait. Genotyping five exonic mutations within FKBP6 revealed a significant association of the SNP g.11040379C>A (p.167H>N) with EBV‐PAT in 216 Hanoverian stallions. The difference among the two homozygous genotypes was 7.62% in EBV‐PAT, corresponding to one standard deviation of EBV‐PAT. In conclusion, in Hanoverian stallions, the FKBP6‐associated SNP g.11040379C>A confers higher conception rates in A/A homozygous and lower conception rates in C/C homozygous Hanoverian stallions. Thus, an FKBP6‐associated missense mutation is significantly associated with stallion fertility.  相似文献   
994.
The term functionality in animal breeding is used for traits that increase the efficiency of production by lowering the input cost, such as animal health and leg weakness related to longevity. The main objective of the study was to investigate the impact of genomic information, in a multivariate variance component analysis, on some of these traits. In addition, the effect of the inclusion was studied by testing the model's prediction ability based on best linear unbiased estimates for fixed and random effects. The material in this study consists of phenotypes from 76 683 animals, of which 4933 animals are genotyped. The heritabilities for front leg conformation, stayability, osteochondrosis and arched back, estimated using the traditional pedigree, were found to be between 0.12 and 0.29. When using the combined genomic and pedigree relationship matrix, the heritabilities were between 0.14 and 0.36. The results show that the combined relationship matrix can be used for the estimation of (co)variance components, and that the predictive ability of the model in this study marginally increases with the inclusion of genomic information.  相似文献   
995.
Infections from Campylobacter jejuni pose a serious public health problem and are now considered the leading cause of foodborne bacterial gastroenteritis throughout the world. Sequencing of C. jejuni genomes has previously allowed a number of loci to be identified, which encode virulence factors that aid survival and pathogenicity. Recently, a Type VI secretion system (T6SS) consisting of 13 conserved genes was described in C. jejuni strains and recognised to promote pathogenicity and adaptation to the environment. In this study, we determined the presence of this T6SS in 63 Spanish C. jejuni isolates from the food chain and urban effluents using whole‐genome sequencing. Our findings demonstrated that nine (14%) strains harboured the 13 ORFs found in prototype strain C. jejuni 108. Further studies will be necessary to determine the prevalence and importance of T6SS‐positive C. jejuni strains.  相似文献   
996.
An experiment was conducted to evaluate the effects of different proportions of ‘Au Grazer’ sericea lespedeza [SL, Lespedeza cuneata (Dum. Cours.) G. Don], a legume rich in condensed tannins (CT), on nutrient intake and digestibility, and to estimate methane (CH4) emissions and 13C isotopic composition (δ13CCH4) from beef steers consuming a forage-based diet. Twenty-five Angus-crossbred steers were distributed in a randomized complete block design (344 ± 48 kg initial BW), and randomly assigned to one of five treatments: 0SL, 25SL, 50SL, 75SL, and 100SL, diets containing 0%, 25%, 50%, 75%, and 100% of SL hay, respectively, mixed with ‘Tifton-85’ bermudagrass hay (Cynodon spp.). The study was carried out for two experimental periods of 21-d each. The statistical model included the fixed effect of treatment and random effects of block, experimental period, and their interaction. Apparent total tract digestibility of crude protein, neutral detergent fiber, and acid detergent fiber was linearly decreased (P < 0.001) by the inclusion of SL. No effects were observed for total CH4 emissions per day, nor for CH4 relative to organic matter intake or digestible organic matter with the inclusion of SL. However, emission of CH4 in relation to intake of CT was affected by treatment (P < 0.001). A linear (P < 0.001) decrease and a quadratic effect (P < 0.001) were observed for δ13C of diets and gas, respectively, in which diets and enteric CH4 with greater inclusion of SL were more depleted in 13C. Moreover, the difference in δ13C between diets and gas (Δδ13C) had a linear decrease (P = 0.001) with the inclusion of SL. The model developed to predict the C3 proportions in the enteric CH4 fitted to predicted values (P < 0.0001). Therefore, greater proportions of SL resulted in lesser CH4 emission when CT intake was considered and the isotopic composition from enteric CH4 was able to predict the contribution of SL in the emissions.  相似文献   
997.
In this study, sn-1,2-, sn-2,3-, and sn-1,3-diacylglycerols were isolated from olive oil, and their urethane derivatives (urethanes) were prepared. Normal-phase high-performance liquid chromatography (NP-HPLC) separation of the urethane isomers was performed and the separate classes were studied by nuclear magnetic resonance (NMR). The use of 1H NMR and homo- and heteronuclear 2D techniques provided a great amount of information in a very short time, particularly when a high-field NMR instrument (700 MHz) was used. Particularly diagnostic for this kind of compound was the glyceridic moiety that presents typical chemical shifts both for carbon and hydrogen. These studies show the usefulness of NMR spectroscopy to recognize clearly the sn-1,3- and, moreover, sn-1,2- with respect to sn-2,3-diacylglycerols, although very minor differences occur between them.  相似文献   
998.
The current status and prospects for the development of the Red Data Book of Russian Soils are discussed. It is argued that this book should become a part of a more general document encompassing not only soils but also other natural resources. The work on the Red Data Book of Natural Resources should include biological, soil, hydrological, geological, landscape, and noospheric objects, as all of them are tightly interrelated and have to be taken into account in the elaboration of the environmental conservation strategy. The noospheric direction implies the study and conservation of cultural objects in their integrity with the environment.  相似文献   
999.
Yukhnovskyi  V.  Polishchuk  O.  Lobchenko  G.  Khryk  V.  Levandovska  S. 《Agroforestry Systems》2021,95(5):855-865

In this article, we investigate the regulation of wind regime by windbreaks of different designs formed by thinning. In particular, we look at the effects of thinning in 52–67 years old oak stands. Based on our results, different windbreaks designs of foliage and aphyllous states influence wind regime of adjacent fields. This research shows that windbreaks of sieve-looking and blown designs with an average optical porosity of 20–25% between the trunks and 5–10% in the crowns have better aerodynamic properties than windbreaks of dense design. The uniformity coefficient of reduction in the airflow ranged between 0.42 and 0.76. There is a clear tendency to decrease wind velocity at a distance of 15H in the leeward side, which has a beneficial effect on agronomic productivity of the surrounding areas. With the transition of windbreaks from full foliage to aphyllous state the optical trunk porosity of plantations increases 1.8–3.0 times, and in crowns—2.5–4.0 times. The windbreaks of blown and sieve-looking designs in the aphyllous state with an average porosity between trunks of 40–50% and in the crowns of 20–30%, regulate more effectively the wind regime in comparison with windbreaks of dense design. According to our findings, the windbreaks of blown design with porosity 40–50% between the trunks and 0–10% in crowns and sieve-looking design have the best ameliorative properties in the region.

  相似文献   
1000.
Peng  Guoxiong  Xie  Jiaqin  Guo  Rong  Keyhani  Nemat O.  Zeng  Deyu  Yang  Puyun  Xia  Yuxian 《Journal of pest science》2021,94(3):969-980
Journal of Pest Science - There is increasing concern about the toxic effects of chemical pesticides on human health and the environment. Many alternatives, however, are viewed as impracticable or...  相似文献   
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