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61.
Chemical Characterization of Rain and Fog Water in the Cervenohorske Sedlo (Hruby Jesenik Mountains, Czech Republic) 总被引:1,自引:0,他引:1
Field study at the Cervenohorske sedlo (1,013 m a.s.l.) (Hruby Jesenik Mountains, the Czech Republic, Central Europe) during 1999–2002 has been conducted in order to analyse the chemistry of rain/snow water using bulk and throughfall collector and fog/cloud water using modified passive Grunow collector. Fog water input to coniferous forest (Picea abies) was quantified using canopy balance method. For all samples pH, and the concentrations of $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ , Ca2+, K+, Mg2+, Na+, Cl?, $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ , and $ {\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}} $ were measured. The volume-weighted mean pH value varied from 4.92 to 5.43 in open bulk precipitation, from 4.30 to 4.71 in throughfall and from 4.66 to 5.23 in fog water. The fog droplets generally contain higher ion concentrations than rainwater. The related enrichment factors lie between 1.1 and 10.7 for the relevant species. The fog samples exhibit higher concentrations of $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ and $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ as compared to the bulk samples during 2000–2002. $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ are 5.7–10.7 times more concentrated in fog water and $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ are 3.4–7.2 times more concentrated in fog water. These differences may result from the height and characteristics of formation of the droplets. Based on canopy balance method, the annual fog water inputs were estimated to be 22 and 19% of rain and snow annual amounts in 1999 and 2000, respectively. For $ {\text{NO}}^{{\text{ - }}}_{{\text{3}}} $ , $ {\text{NH}}^{{\text{ + }}}_{{\text{4}}} $ , and $ {\text{SO}}^{{{\text{2 - }}}}_{{\text{4}}} $ , the contribution of fog deposition in total (bulk + fog) deposition is estimated as 54, 47, and 42%, respectively. 相似文献
62.
63.
Elbieta Brzuska 《Aquaculture Research》2004,35(14):1318-1327
The investigation concerned the reproduction effects in carp females of the Hungarian strain 8, Polish strain 2 and French strain F of ovulation stimulation with carp pituitary homogenate (0.3 mg kg?1 and after 12 h 2.7 mg kg?1) or [D‐Tle6, ProNHEt9]GnRH (Lecirelin) with metoclopramide (15 μg kg?1 and 10 mg kg?1 respectively). The ovulation stimulators did not affect the weight of eggs (expressed in g and as the percentage of female body weight). However, in the group treated with pituitary homogenate (I) the least‐square means estimated for these parameters were higher than in the group treated with Lecirelin (II). A statistically significant (P≤0.05) difference in the mean percentage of living embryos after 48‐h incubation was observed between groups I and II, with the eggs obtained from females of group I being of better quality. The origin of females significantly (P≤0.05) affected the weight of eggs. The weight of eggs from females of Hungarian strain 8 was higher (P≤0.05) than the weight of eggs of the other two lines. With respect to parameters for egg quality (percentage of fertilized eggs and percentage of living embryos after 24‐, 36‐ and 48‐h incubation), no effect of the origin of females was observed. The interaction between the spawning agent and the origin of the females was not statistically significant with respect to the two parameters for the weight of the eggs. The least‐square means test for the investigated interaction showed that after the application of pituitary homogenate, the weight of eggs obtained from strains 8 and F was similar (respectively 711.2 g and 665.0 g). However, after the application of Lecirelin the females of strain 8 yielded eggs of a high weight (934.3 g) and those of strain F of a very low weight (373.2 g). A statistically significant (P≤0.05) interaction between ovulation stimulator and origin of females was recorded for the percentage of living embryos after 24‐ and 36‐h incubation. A dependence was found between the latency time and the reproduction effects. 相似文献
64.
Cryptosporidium in farm rabbits is not often recognised due to a low prevalence and asymptomatic course of infection. Nonetheless, incidences of fatal diarrhoeic diseases are frequently noticed in the rabbitries. In this article, we report an outbreak where there was massive mortality among farm rabbits associated with Cryptosporidium infection. The disease was characterised by profuse diarrhoea resulting in the death of rabbits. A pooled faecal sample was screened for a presence of parasites using microscopy methods. In the tested sample no other parasites other than Cryptosporidium oocysts were found. Further identification of the parasite species was performed at a molecular level, using the 18 SSU rRNA, COWP and LIB13 PCR followed by a subtyping at the GP60 gene locus. Sequence analysis of GP60 gene fragment revealed the presence of a novel subtype VbA24 of Cryptosporidium cuniculus. In this outbreak a Cryptosporidium protozoan parasite played a major role in the etiology of the gastrointestinal disorders in rabbits resulting in massive mortality of the infected animals. 相似文献
65.
Sana Hireche Omar Bouaziz Djahida Djenna Sabrina Boussena Rachida Aimeur Rachid Kabouia El Hacène Bererhi 《Tropical animal health and production》2014,46(2):467-473
A cross-sectional study was carried out to estimate prevalence of Chlamydophila spp. antibodies and to investigate risk factors associated with chlamydial infection in 552 ewes between March 2011 and January 2012 in the province of Constantine. Anti-Chlamydophila antibodies were detected using an indirect enzyme-linked immunosorbent assay kit in 24.5 % of examined sera. Of the herds, 70.4 % had at least one seropositive animal. A pretested structured questionnaire was administered in order to collect information on individual animal health and herd management practices. Chi-square analysis and multivariable logistic regression model were used to identify risk factors related to Chlamydophila seropositivity. Univariable analysis revealed 17 variables with p?<?0.25 that were offered to the multivariable logistic regression model which in turn identified 12–23 months age group (OR?=?5.903, 95 % CI (OR)?=?1.690; 20.618) and not using disinfectants (OR?=?2.099, 95 % CI (OR)?=?1.314; 8.065) as risk factors for Chlamydophila spp. seropositivity. Moreover, occurrence of stillbirth problem (OR?=?3.682, 95 % CI (OR)?=?1.825; 7.430) and 5–10 % mortality rate in young lambs (OR?=?2.584, 95 % CI (OR)?=?1.058; 6.310) were significantly associated with seropositivity to Chlamydophila spp. On the other hand, availability of veterinary service was identified as a protective factor (OR?=?0.161, 95 % CI (OR)?=?0.051; 0.511). 相似文献
66.
Stéphane Kroemer Farid El Garch Delphine Galland Jean-Luc Petit Frédérique Woehrle Henri-Jean Boulouis 《Comparative immunology, microbiology and infectious diseases》2014
A monitoring program of the pre-treatment susceptibility of clinical isolates of bacteria from diseased dogs and cats was active between the years 2002 and 2009. Susceptibility of each isolated strain to a panel of nine antibiotics (amoxicillin/clavulanic acid, ampicillin, penicillin, clindamycin, doxycycline, enrofloxacin, marbofloxacin, trimethoprim and trimethoprim/sulfamethoxazole) was assessed. The Minimum Inhibitory Concentration (MIC) of marbofloxacin was also determined by a standardized microdilution technique following CLSI recommendations. In total, 1857 bacterial strains were collected throughout Europe from cases of otitis, respiratory, urinary and dermatological infections. Although bacterial susceptibility varied for each of the antibiotics within the panel, patterns of susceptibility were similar to those described in the literature for comparable time periods and geographical areas. With a clinical resistance varying from 0 to 14.48% against the isolated strains, marbofloxacin susceptibility was very high and remains an effective antibiotic for the treatment of otitis, urinary, respiratory and dermatological infections in companion animals. 相似文献
67.
This study was designed to study the effect of short‐term supplementation with rumen‐protected fat during the late luteal phase on reproduction and metabolism of sheep during breeding season. Seventy‐six ewes (Rahmani, Barki and Awassi × Barki) were allocated to two groups considering genotype: the control ewes (C‐group) received a maintenance diet, and the fat‐supplemented ewes (F‐group) received the maintenance diet plus 50 g/head/day of rumen‐ protected fat (Megalac) for 9 days during which oestrus was synchronized. The latter had been accomplished using double intramuscular injection of prostaglandin F2α (PGF2α) 11 days apart. Ovarian activity, serum concentration of cholesterol, glucose, insulin and reproductive performance variables were recorded. Data were analysed considering treatment (group) and genotype. Supplementation had positive effects on the overall mean serum concentrations of cholesterol (p < 0.05), glucose (p < 0.05) on day 6 of nutritional treatment and insulin (p = 0.07) on day 8. Fat supplementation did not affect the total number of follicles, follicle populations and ovulation rate. However, fat‐supplemented Rahmani ewes tended to have higher ovulation rate compared with other breeds (treatment × breed interaction, p = 0.06). Treatment also did not affect the mean concentration of serum estradiol or progesterone. Supplemented ewes had higher conception (p = 0.06) and lambing rates (p < 0.05) compared with control. In conclusion, short‐term supplementation with rumen‐protected fat as a source of energy around breeding time improved metabolism, conception and lambing rates of ewes without effects on steroidogenic capacity and ovarian activity being apparent. 相似文献
68.
Rafał Ważny 《Annals of Forest Science》2014,71(7):801-810
Context
The requirement for rebuilding forecrop stands besides replacement of meadow vegetation with forest plants and formation of soil humus is the presence of a compatible ectomycorrhizal (ECM) fungal community.Aims
This study aims to assess ectomycorrhizal fungi diversity associated with silver fir (Abies alba Mill.) seedlings regenerating in silver fir stands and Scots pine forecrops.Methods
One-year-old seedlings were sampled in six study sites: three mature fir forests and three pine forests. ECM fungi were identified by polymerase chain reaction amplification and sequencing of the internal transcribed spacer of rDNA.Results
The mean mycorrhizal colonization exceeded 90 %. Thirty-six ectomycorrhizal taxa were identified in fir stands and 23 in pine forecrops; ten out of these species were common to both stands. The fungal communities were different between study sites (R?=?0.1721, p?=?0.0001). Tomentella stuposa was the only species present at all sites.Conclusion
Silver fir seedlings in Scots pine forecrops supported smaller ECM fungal communities than communities identified in mature silver fir stands. Nevertheless, fungal colonization of seedling roots was similar in both cases. This suggests that pine stands afforested on formerly arable land bear enough ECM species to allow survival and growth of silver fir seedlings. 相似文献69.
Andrzej K Siwicki Zdzisaw Zak John C Fuller Jr Steven Nissen Sylwia Trapkowska Edward Gbski Agata Kowalska Krzytof Kazu & Elbieta Terech-Majewska 《Aquaculture Research》2006,37(2):127-131
Studies have shown that in both in vitro and in vivo tests, β‐hydroxy‐β‐methylbutyrate (HMB) increases the nonspecific cellular and humoral immune response and protection against diseases in animals. The present study examines the influence of HMB on nonspecific humoral defense mechanisms and protection against furunculosis in pikeperch (Sander lucioperca). β‐hydroxy‐β‐methylbutyrate was fed in a pelleted ration of 50 mg kg?1 feed day?1 for 4 weeks. Blood was drawn from 12 HMB‐fed and control‐fed pikeperch. The lysozyme and ceruloplasmin activities in the plasma, total immunoglobulin (Ig) levels, and total serum protein were analysed prior to and then after 2 and 4 weeks of HMB ingestion. After 4 weeks of HMB ingestion, a challenge test was performed by injecting the fish with live pathogenic Aeromonas salmonicida bacteria. β‐hydroxy‐β‐methylbutyrate at a dose of 50 mg kg?1 feed resulted in a statistically significant (P<0.05) increase in the lysozyme activity of the plasma, total Ig, and serum protein levels. Additionally, reduced mortality (40%) after the in vivo challenge with pathogenic A. salmonicida suggested that HMB‐activated nonspecific protection against furunculosis in pikeperch. 相似文献
70.
Gamal O. El Naggar George John Mahmoud A. Rezk Waheed Elwan Mohammed Yehia 《Aquaculture (Amsterdam, Netherlands)》2006,261(3):904-907
The development of a reliable methodology for spawning of African catfish, Clarias gariepinus without the use of hormone injections would greatly improve the prospects of aquaculture in Africa. Earlier work has shown that it is possible to produce C. gariepinus fingerlings by subjecting the broodfish to a physical stress of reduced water depth and/or increased temperature. The hypothesis that C. gariepinus could be induced to spawn through a combined physical stress of lowered water level and increased stocking density was tested in concrete tanks. Three water levels (25, 50 and 75 cm) and three stocking densities (2, 4 and 6 pairs of broodfish at a 1:1 sex ratio in each hapa) were tested. Water depth in the tanks and brood fish density in the hapas affected spawning success. The percentage of spawning females was significantly higher when broodfish were stocked at 2 and 4 pairs in each hapa at water levels of 25 cm or 50 cm. There was no significant difference in spawning response between the 25 and 50 cm depths while a significant difference was seen between the 75 cm and both 25 and 50 cm depths. The results indicate optimum levels and densities for enhancing spawning success in C. gariepinus. 相似文献