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1.
Jamie K. Norris Paul Slusarewicz Martin K. Nielsen 《International journal for parasitology》2019,49(11):885-892
The efficacy of anthelmintic treatments against populations of endoparasites infecting livestock throughout the world is decreasing. To mitigate this, the use of fecal egg counts is recommended to determine both the necessity, and to ensure the appropriate choice, of anthelmintic treatment. Traditionally, and in order to facilitate easier identification and/or enumeration, samples are analysed after separating eggs from other fecal particulates by exposing them to a solution with a density higher than that of the eggs, but lower than the remaining fecal contents. While many parasite egg flotation protocols exist, little is known about the characteristics of these eggs with respect to their movement through a flotation solution. In this study, we have demonstrated a novel method for the observation and quantification of microscopic (65–100 µm) objects as they experience unassisted flotation. This also represents, to our knowledge for the first time, that the flotation of parasite eggs has been observed and their movement characteristics quantified as they float through solution. Particle tracking and video analysis software were utilised to automatically detect and track the movement of individual eggs as they floated. Three 30 s videos and one 2 min video of each egg type were analysed. If the first 30 s of video were discounted, the differences in mean flotation speed among all videos was statistically significant between egg types (P = 0.0004). Strongyle type eggs (n = 201) moved the fastest with a mean 51.08 µm/s (95% confidence interval: 47.54–54.62). This was followed by Parascaris spp. (n = 131) and Anoplocephala perfoliata eggs (n = 322), with mean speeds of 44.43 µm/s (95% confidence interval: 39.47–49.4) and 31.11 µm/s (95% confidence interval: 29.6–32.61), respectively. This method for evaluating the mean speed of passive flotation may represent a first step towards further optimizing fecal egg flotation and be of interest to parasitologists and veterinary practitioners. 相似文献
2.
Denaturing gradient gel electrophoresis (DGGE) was applied to the 16S-23S rRNA intergenic spacer region (ISR) as a means to evaluate strain level differences in Escherichia coli. The ISRs of 81 environmental E. coli isolates obtained from bovine, poultry, and human sources yielded a total of 41 unique DGGE banding patterns, with identical patterns and common bands within each source and no overlapping patterns among sources. An additional 51 isolates from two nearby streams yielded 45 unique banding patterns with no overlap between sites. However, two of the isolates from the streams had identical banding patterns to those from two of the source isolates, resulting in a total of 84 unique DGGE banding patterns out of 132 isolates identified in this study. These results revealed high diversity among environmental E. coli isolates, which made it difficult to unambiguously ascribe strains found in water samples to specific host organisms. 相似文献
3.
Although the Tsushima leopard cat (Prionailurus bengalensis euptilurus) is one of the most endangered mammals in Japan, its reproductive physiology and endocrinology have been not elucidated. The objective was to establish the non-invasive monitoring of reproductive endocrinology in a female Tsushima leopard cat and to identify the types of fecal reproductive steroid metabolites in this species. Fecal concentrations of estrogen and progestin were determined by enzyme immunoassays, from 60 d before to 60 d after the last copulation, during three pregnancies. Fecal estrogen metabolite concentrations were increased before/around the mating period and after mid-pregnancy. Fecal progestin metabolite concentrations increased after the last copulation and remained high during pregnancy. The gestation period was 65.0 ± 0.6 d (mean ± SD). Fecal extracts were separated by high-performance liquid chromatography for identification of fecal metabolites. Fecal estrogens were identified as estradiol-17β and estrone. Fecal progestins during pregnancy contained 5α-reduced pregnanes: 5α-pregnan-3α-ol-20-one, 5α-pregnan-3β-ol-20-one and 5α-pregnan-3,20-dione, and nonmetabolized progesterone was barely detected in feces. In conclusion, measurement of fecal estrogen and progestin metabolites was effective for noninvasive reproductive monitoring in the Tsushima leopard cat. An immunoassay for fecal estradiol-17β concentrations seemed useful to monitor follicular activity, whereas an immunoassay with high cross reactivity for 5α-reduced pregnanes was useful to monitor ovarian luteal activity and pregnancy. 相似文献
4.
5.
观察粪菌移植(FMT)对难治性肠易激综合征的治疗效果, 为该病的治疗提供参考。
招募我院32例难治性肠易激综合征患者并分为治疗组(
治疗组患者FMT治疗前、治疗1个月和治疗3个月时IBS-SSS评分和粪便分型逐渐降低(均
FMT对难治性肠易激综合征有一定的临床疗效, 且安全可靠。
6.
The aim of the present study was to investigate the safety and efficacy of deslorelin, a GnRH agonist, implants in suppressing estrus behavior and matings in a controlled ambient environment in feline queens in the presence of a tomcat. Local and utero-ovarian side effects of deslorelin implants were also investigated. The queens were housed in groups and assigned to one of three treatments: group 1 received 9.5 mg deslorelin implants (N = 14), group 2 received 5 mg megestrol acetate tablets and 9.5 mg deslorelin implants (N = 7), and group 3 were given placebo implants (N = 7). All implants were placed subcutaneously cranial to the interscapular region under xylazine hydrochloride sedation. Ovarian activity was monitored by fecal estradiol (E2) analyses. The animals were observed daily and checked individually at three-day intervals for behavioral signs of estrus. After 18.5 mo of trial, queens were ovariohysterectomized, and ovaries and uteri were weighed and evaluated histologically. E2 levels were significantly lower in group 1 and 2 than in group 3 with an average of 128.48 ± 19.97 ng/g, 90.44 ± 7.16 ng/g and 283.26 ± 39.21 ng/g, respectively, excepting the first week of treatment. After inserting implants an initial estrus-like increase in fecal E2 concentrations occurred in all treated queens except one female in group 2. Ovarian and uterine weights were significantly different among the groups (P < 0.01), and were lowest in groups 1 and 2. Primordial and primary follicle numbers were significantly higher in groups 1 and 2 than in group 3 (P < 0.001). Endometrial gland, antral follicle, and corpus luteum (CL) numbers were highest in group 3 (P < 0.01, 0.001, and 0.001, respectively) compared with groups 1 and 2. Deslorelin implants successfully suppressed estrus behavior and E2 secretion in queens for 18.5 mo of the study period. Further investigations are needed to demonstrate the effects of GnRH agonists on ovarian interstitial tissue. 相似文献
7.
Rodolfo Martínez-Mota Carolina Valdespino Juan Arturo Rivera Rebolledo Rupert Palme 《International journal of primatology》2008,29(5):1365-1373
Measuring fecal glucocorticoid metabolites is now a common practice to assess the stress response in primates. Nevertheless,
it is important to validate the utilized immunoassay for each primate species before the technique is applied to populations
in the wild. We determined the stress response of black howlers (Alouatta pigra) via 2 different group-specific enzyme immunoassays (EIAs). 11-oxoetiocholanolone EIAs are suited to assess the stress response
of black howlers via fecal glucocorticoid metabolites. Levels of fecal glucocorticoid metabolites increased after we applied
a stressor, i.e. anesthesia, reaching peak concentrations 24–96 h poststressor. Both basal and stress-induced fecal glucocorticoid
metabolite levels showed individual variations. The increase of fecal glucocorticoid metabolites after the stressor (paralleling
increases in serum) indicates that one can effectively measure adrenocortical activity in Alouatta pigra via these 2 enzyme immunoassays. However, it is important to consider individual variations in the excretion of fecal glucocorticoid
metabolites when planning field endocrinological research on Alouatta pigra. Fecal glucocorticoid metabolite excretion takes 1–3 d poststressor depending on the individual. Further, there is an important
individual variability in the concentrations of glucocorticoid metabolites, which might reflect differences in stress reactivity
or fecal glucocorticoid metabolite metabolism and excretion. 相似文献
8.
Elisabet Börjesson Annika Sundin Rhys Leeming Lennart Torstensson 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1998,713(2):62
A new method has been developed to determine a number of sterols in urine using non-chlorinated solvents, namely methyl tert.-butyl ether and methanol (the MTB method). The method involves liquid–liquid extraction, saponification, reextraction, silylation and final identification and quantification by GC–FID. The sterols determined were coprostanol, epicoprostanol, cholesterol and dihydrocholesterol. 5α-Cholestane was used as internal standard. The limit of detection for the sterols in this experiment was 2 μg l−1 urine. Recovery of coprostanol over the range 5–100 μg l−1 urine by this method was between 80 and 92%. 相似文献
9.
10.
A.C. Cockcroft H.H. Du Preez 《Journal of experimental marine biology and ecology》1990,140(3):159-171
Nitrogen excretion and assimilation efficiencies in Lithognathus mormyrus (Linnaeus), a marine teleost present in high-energy surf zones in Algoa Bay, South Africa, were determined under controlled laboratory conditions at 15, 20 and 25 °C. Ammonia was the major form of nonfaecal nitrogen excreted by starved and fed L. mormyrus. Urea and amino acids were secondary excretory products. Ammonia excretion rates were temperature independent and the excretion rates of fed fish were significantly higher than starved fish at 20 and 25 °C but not at 15 °C. The mass component (b) of the mass/ammonia excretion equation was temperature independent and ranged from 0.590 to 0.669 and from 0.670 to 0.767 for starved and fed fish, respectively. The mean percentage of food energy lost via the dissolved nonfaecal excretory products (exogenous plus endogenous) was 4.12%. Assimilation efficiencies ranged from 71.89 to 98.78% for dry matter and from 96.89 to 99.88% on an energy basis. The combined nonfaecal and faecal energy loss was calculated at 10.11% of the ingested energy. The omnivorous ichthyofauna present in the surf zone ecosystem recycle 33 g N · m strip · yr−1. This constitutes < 1 % of total phytoplankton nitrogen requirements. 相似文献