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41.
AIMS: An internal positive control for Cryptosporidium and Giardia monitoring was evaluated for use in routine water monitoring quality control. The control, known as ColorSeed C&G (BTF Pty Ltd, Sydney, Australia), is a suspension containing exactly 100 Cryptosporidium oocysts and 100 Giardia cysts that have been modified by attachment of Texas Red to the cell wall, allowing them to be differentiated from unmodified oocysts and cysts. The control enables recovery efficiencies to be determined for every water sample analysed. METHODS AND RESULTS: A total of 494 water samples were seeded with ColorSeed C&G and with unlabelled Cryptosporidium and Giardia and then analysed. Additionally, the robustness of the ColorSeed labelling was challenged with various chemical treatments. Recoveries were significantly lower for the ColorSeed Texas Red labelled Cryptosporidium and Giardia than recoveries of unlabelled Cryptosporidium and Giardia. However, the differences in recoveries were small. On average ColorSeed Cryptosporidium recoveries were 3.3% lower than unlabelled Cryptosporidium, and ColorSeed Giardia recoveries were 4% lower than unlabelled Giardia. CONCLUSIONS: ColorSeed C&G is suitable for use as an internal positive control for routine monitoring of both treated and raw water samples. SIGNIFICANCE AND IMPACT OF THE STUDY: The small differences in recoveries are unlikely to limit the usefulness of ColorSeed C&G as an internal positive control. The ColorSeed labelling was found to be robust after different treatments. 相似文献
42.
The per capita home range area of Japanese macaques,Macaca fuscata, is significantly smaller in evergreen forest than in deciduous forest, though a corresponding difference in food resource
utilization patterns has never been described. The present study compared the home range utilization pattern of Japanese macaques
living in two habitats: the Yakushima population inhabits an evergreen forest, while the Kinkazan population inhabits a deciduous
forest. We found that in the Yakushima population, (1) food density was higher; (2) inter-feeding bout sites distance was
shorter; (3) daily travel distance was shorter; (4) home range size was smaller; and (5) the unit value of the main home range
was higher, than in the Kinkazan population. Yakushima groups utilized a small home range area intensively, compared to Kinkazan
groups. We also found that a Yakushima group shared 24% of its main home range with neighboring groups, though a Kinkazan
group shared only 10% with other groups. It is supposed that food distribution affects daily ranging pattern, and ultimately
the social relationships between groups in Japanese macaques. 相似文献
43.
Improving Quality Control of Contagious Caprine Pleuropneumonia Vaccine with Tandem Mass Spectrometry 下载免费PDF全文
François Thiaucourt Olivier Pible Guylaine Miotello Nick Nwankpa Jean Armengaud 《Proteomics》2018,18(17)
Vaccines to protect livestock against contagious caprine pleuropneumonia (CCPP) consist of inactivated, adjuvanted antigens. Quality control of these vaccines is challenging as total protein quantification provides no indication of protein identity or purity, and culture is not an option. Here, a tandem mass spectrometry approach is used to identify the mycoplasma antigen contained in reference samples and in commercial CCPP vaccines. By the same approach, the relative amounts of mycoplasma antigen and residual proteins originating from the production medium are determined. Mass spectrometry allows easy and rapid identification of the peptides present in the vaccine samples. Alongside the most probable mycoplasma species effectively present in the vaccines, a very high proportion of peptides from medium constituents are detected in the commercial vaccines tested. 相似文献
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Jianghui Zhang Xueqing Zhang Kexin Zhang Xiaoyan Lu Guojing Yuan Huayu Yang Haiyun Guo Zhihui Zhu Tianli Wang Jiahu Hao Ying Sun Puyu Su Zhihua Zhang 《Polish journal of microbiology》2022,71(2):241
With the development of genome sequencing, many researchers have investigated the mechanism by which the intestinal microbiota influences sleep across the brain-gut axis. However, the relationship between gut microbiota and sleep disorder remains unclear. Thus, we studied the difference in gut microbiota composition between poor sleep quality- and normal populations, which helps set the ground for future research. The recruited college students provided baseline information and stool samples and completed the Pittsburgh Sleep Quality Index (PSQI). We compared the two groups’ gut microbiota composition and functional differentiation by using the 16S rRNA gene sequencing analysis. The main bacterial difference and the most critical effect were mainly concentrated within Tenericutes and Elusimicrobia. Compared with the healthy control group, some functions of the gut microbiota were impaired in the poor sleep quality group, such as butanoate metabolism and propanoate metabolism. Bacterial taxa with significant differences raised the possibility for future diagnosis and treatment of sleep problems. 相似文献
46.
S. Nowaczewski M. Babuszkiewicz T. Szablewski K. Stuper-Szablewska R. Cegielska-Radziejewska Ł. Tomczyk S. Kaczmarek A. Sechman M.W. Lis M. Kwaśniewska P. Racewicz Ł. Jarosz A. Ciszewski T. Nowak M. Hejdysz 《Animal : an international journal of animal bioscience》2022,16(7):100564
The transfer of hatchability results obtained under experimental conditions to the commercial ground with a positive financial effect proves the value and usefulness of these data. On the other hand, finding results on commercial processes of broiler breeders’ egg incubation in the literature is challenging. The presented study aimed to determine the effects of egg weight and storage time on the physical, biochemical characteristics of hatching eggs, embryogenesis and hatchability in Ross 308 broiler breeders. On the laying day, the eggs were divided into four weight groups: S – small eggs (57–61 g), M – medium eggs (62–66 g), L – large eggs (67–71 g), and XL – extra-large eggs (72–76 g). The eggs were then stored for 3, 7, 14, and 21 days under controlled conditions. As the egg storage time increased, a decrease in the yolk quality (lower index) was observed. The highest Haugh units were found in eggs from the S and M groups. The cholesterol content of the M, L, and XL groups was lower on days 7, 14, and 21 as compared to that of eggs only stored for 3 days. Egg weight loss during incubation decreased with an increase in the egg weight. An extension of the egg storage time caused an increase in the loss of egg weight. On the 14th and 18th days of hatching, an increase in the eggshell temperature was noted with an increase in the weight of the egg. The eggs stored for 7 days were characterised by the highest shell temperature on each day. The highest hatchability percentage was recorded for the M group. The hatchability rate decreased with the prolongation of the storage time, while the number of crippled chicks after hatching increased. The results confirmed that the increased weight of the eggs and prolonged storage time (14 and 21 days) increased the weight and decreased the length of the newly hatched chicks, respectively. Chicks from the heaviest eggs and those stored for 14 and 21 days showed poor results on the Pasgar score® test. The observations indicate the need to adopt various (of those available) methods to assess the quality of newly hatched chicks in hatcheries in order to produce high-quality broiler chickens. The results also indicate that prolonged egg storing beyond 14 days may affect the thyroid hormone economy during the hatching of chicks, especially in the XL group. 相似文献
47.
In order to test the response of phytoplankton to anthropogenic pressure, data of chlorophyll a concentration, phytoplankton abundance, and composition are analyzed in relation to anthropogenic pressure gradient and environmental variables such as temperature, salinity and nutrients. Investigated sites encompassed wide tropic range according to a preliminary determination of anthropogenic pressure, quantified through the LUSI index. Statistical analyses indicated nitrates and silicates as proxies of freshwater influence, and phytoplankton single metrics such as concentrations of chlorophyll a and abundances as indicators of anthropogenic pressure. Boundary values for different water quality classes for coastal waters under indirect freshwater influence (Type II) are obtained according to gradient between concentration of chlorophyll a and pressure index (LUSI), which empirically fit to exponential equation. The response of phytoplankton diversity was not linear, as the highest diversity was observed in the area with intermediate disturbance level. CCA analysis identified Skeletonema marinoii, Scrippsiella trochoidea, Guinardia flaccida, Leptocylindrus spp., Prorocentrum spp., Proboscia alata, Eutreptiella spp., and Pseudonitzschia spp. as local eutrophication indicators, whose abundances increased with nutrients loads. 相似文献
48.
49.
A knowledge of the effective size of a population (Ne) is important in understanding its current and future evolutionary potential. Unfortunately, the effective size of a hierarchically structured population is not, in general, equal to the sum of its parts. In particular, the inbreeding structure has a major influence on Ne. Here I link Ne to Wright's hierarchical measures of inbreeding, FIS and FST, for an island-structured population (or metapopulation) of size NT. The influence of FST depends strongly on the degree to which island productivity is regulated. In the absence of local regulation (the interdemic model), interdemic genetic drift reduces Ne. When such drift is combined with local inbreeding under otherwise ideal conditions, the effects of FIS and FST are identical: increasing inbreeding either within or between islands reduces Ne, with Ne = NT/[(1 + FIS)(1 + FST) ? 2FISFST]. However, if islands are all equally productive because of local density regulation (the traditional island model), then Ne = NT/[(1 + FIS)(1 –FST)] and the effect of FST is reversed. Under the interdemic model, random variation in the habitat quality (and hence productivity) of islands act to markedly decrease Ne. This variation has no effect under the island model because, by definition, all islands are equally productive. Even when no permanent island structure exists, spatial differences in habitat quality can significantly increase the overall variance in reproductive success of both males and females and hence lower Ne. Each of these basic results holds when other nonideal factors are added to the model. These factors, deviations from a 1:1 sex ratio, greater than Poisson variance in female reproductive success, and variation in male mating success due to polygynous mating systems, all act to lower Ne. The effects of male and female variance on Ne have important differences because only females affect island productivity. Finally, it is noted that to use these relationships, FIS and FST must be estimated according to Wright's definition (and corrected to have a zero expectation under the null model). A commonly used partitioning (θ, θg) can be biased if either island size or the number of islands is small. 相似文献
50.
An avian equivalent of make-up? 总被引:2,自引:0,他引:2
We report that a long-distance migrating shorebird, the red knot, makes a complete switch from commonly occurring monoester preen waxes to a much rarer class of higher-molecular-weight diester waxes at the time of take-off to the high arctic breeding grounds. The cold arctic climate would have required a lowering of wax-viscosity, and thus, a shift in the reverse direction. We propose that a sexually selected need for a brilliant plumage has lead to this conter-intuitive temporary shift from monoesters to diester waxes. The difficulty of application of the diester preen waxes under cold conditions would ensure the reliability of the quality-signalling function of this most probably sexually selected trait. 相似文献