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1.
Anuj Kumar Pavla Ryparovà Bohumil Kasal Stergios Adamopoulos Petr Hajek 《Wood material science & engineering》2020,15(1):57-63
ABSTRACTBamboo scrimber is one of the most emerging structural materials for future building applications and it possesses properties comparable to other natural wood-based engineered materials such as glulam, laminated veneer lumber and cross-laminated timber. The goal of this work was to study the decay resistance of bamboo scrimber against white-rot (Trametes versicolor) and brown-rot fungi (Serpula lacrymans). Bamboo scrimber samples were incubated in petri dishes with the wood-decaying fungi and the weight loss after 12 weeks was measured. The surface morphology of fungal-degraded bamboo scrimber was evaluated using optical microscopy. Based on the percentage weight loss, bamboo scrimber could be classified as highly resistant against bio-deterioration by white and brown-rot fungi. 相似文献
2.
Ji&#;í &#;ehulka Bohumil Mina&#;ík Václav Adamec & Eva &#;ehulková 《Aquaculture Research》2005,36(1):22-32
This study was aimed at construction of reference (physiological) value intervals determined by lower 2.5% and upper 97.5% quantiles for total plasma protein (TPP) in farmed rainbow trout, Oncorhychus mykiss (Kamloops strain), aged 10–12 months (n=755). Total plasma protein in male trout from raceway culture was found to be significantly greater (38–58.3 g L?1) relative to females (31–51.5 g L?1). Total plasma protein in trout from cage culture was significantly greater (32–54 g L?1) compared with the raceway culture (31–49 g L?1). Moderate product–moment correlations between TPP and cholesterol (r=0.8730), TPP and total calcium (r=0.8188), TPP and alanine aminotransferase (r=0.6200) and between TPP and aspartate aminotransferase (r=0.6430) were estimated. Proteinaemia was explained as a metabolic response to feed content, infections of bacterial or viral aetiology or to intoxications. 相似文献
3.
Three strains of mice, BALB/c, IL-12 knock-out (KO) and INF-gamma knock-out, were chosen as an experimental model for the study of intestinal immunity induction against Encephalitozoon cuniculi Levaditi, Nicolau et Schoen, 1923 infection. Mice were infected perorally with 10(7) spores and re-infected with the same dose 70 days after the first infection. The anti-E. cuniculi IgA, IgG and IgM responses in sera and extracts of stool samples were determined by ELISA. Results have shown specific antibody production in the sera and intestinal secretions of all three strains of mice induced orally by E. ciniculi spores. BALB/c mice developed a stronger humoral immune response than IL-12 KO mice. The lowest antibody response developed in INF-gamma KO mice that succumbed to the infection within 28 days post infection. 相似文献
4.
Martin Kváč Michaela Kestřánová Martina Pinková Dana Květoňová Jana Kalinová Pavla Wagnerová Michaela Kotková Jiří Vítovec Oleg Ditrich John McEvoy Brianna Stenger Bohumil Sak 《Veterinary parasitology》2013,191(3-4):218-227
We describe the morphological, biological, and molecular characteristics of Cryptosporidium pig genotype II and propose the species name Cryptosporidium scrofarum n. sp. to reflect its prevalence in adult pigs worldwide. Oocysts of C. scrofarum are morphologically indistinguishable from C. parvum, measuring 4.81–5.96 μm (mean = 5.16) × 4.23–5.29 μm (mean = 4.83) with a length to width ratio of 1.07 ± 0.06 (n = 400). Oocysts of C. scrofarum obtained from a naturally infected pig were infectious for 8-week-old pigs but not 4-week-old pigs. The prepatent period in 8-week-old Cryptosporidium-naive pigs was 4–6 days and the patent period was longer than 30 days. The infection intensity of C. scrofarum in pigs was generally low, in the range 250–4000 oocysts per gram of feces. Infected pigs showed no clinical signs of cryptosporidiosis and no pathology was detected. Cryptosporidium scrofarum was not infectious for adult SCID mice, adult BALB/c mice, Mongolian gerbils (Meriones unguiculatus), southern multimammate mice (Mastomys coucha), yellow-necked mice (Apodemus flavicollis), or guinea pigs (Cavia porcellus). Phylogenetic analyses based on small subunit rRNA, actin, and heat shock protein 70 gene sequences revealed that C. scrofarum is genetically distinct from all known Cryptosporidium species. 相似文献
5.
Martin Kv
Dagmar Hanzlíkov Bohumil Sak Dana Kv to&#x;ov 《Veterinary parasitology》2009,160(3-4):319-322
A total of 413 pig faecal samples were collected from pre-weaners (119), starters (131), pre-growers (123) and sows (40) from a farm with a closed breeding system segmented into two breeding complexes and a growing complex in the region of Vysočina, Czech Republic and screened for the presence of Cryptosporidium using staining methods and genotyping (SSU rRNA). Cryptosporidium oocysts were detected by microscopy in the faeces of 21.1% of the samples (87/413). Sequence analyses and RFLP identified C. suis in 44, Cryptosporidium pig genotype II in 23 and C. muris in 2 samples. No mixed infections were found.Pigs under 7 weeks of age were infected with C. suis only. Cryptosporidium pig genotype II was found in animals from 7 weeks of age. No relationship was found between diarrhoea and any Cryptosporidium infection in any of the different age groups (P < 0.05). The pre-weaned pigs shed significantly more Cryptosporidium oocysts than older pigs and it was associated with C. suis infection. 相似文献
6.
Mass death of farmed brook trout Salvelinus fontinalis reared in raceway culture on a commercial fish farm was recorded in May. The condition was caused by natural infection with external signs of Flavobacterium columnare. Haematological analyses were carried out from peripheral blood from 10 fish from each group. Anaemia was characterized by a reduced erythrocyte count and lower haemoglobin levels; the values of mean corpuscular volume and mean corpuscular haemoglobin were higher and the values of mean corpuscular haemoglobin concentration were decreased. Clinical chemistry analyses in blood plasma indicated decreased levels of total protein, glucose and total calcium and an increase in the urea level. Among the four enzymes analysed, a catalytic activity reaching multiples of the normal level was found in alanine aminotransferase, aspartate aminotransferase and lactate dehydrogenase. The catalytic concentration of alkaline phosphatase was decreased. Electrophoretic analyses of the plasma protein indicated a reduced level of albumin. The moribund fish had a higher hepatosomatic index and their condition coefficient after Fulton and after Clark was also higher. 相似文献
7.
Martin Kvác Bohumil Sak Dana Kvetonová Oleg Ditrich Lada Hofmannová David Modry Jirí Vítovec Lihua Xiao 《Veterinary parasitology》2008,153(3-4):363-367
Farm ruminants were infected experimentally with four mammalian gastric Cryptosporidium, namely Cryptosporidium andersoni LI03 originated from cattle and three isolates of Cryptosporidium muris from brown rat (isolate RN66), Bactrian camel (isolate CB03) and firstly characterized isolate from East African mole rat (isolate TS03). Sequence characterizations of the small-subunit rRNA gene showed that the LI03 isolate was C. andersoni and the other three isolates belonged to C. muris, although the TS03 isolate showed unique sequence variations (one single nucleotide change and four nucleotide insertions). C. andersoni LI03 was infectious for calves only, whereas lambs and kids were susceptible to C. muris CB03. C. muris TS03 and RN66 were not infectious for any farm ruminants. Infection dynamics including prepatent and patent period and infection intensity of the isolates used differed depending on the host species, but no clinical signs of cryptosporidiosis were observed in any of experimentally infected hosts. Cryptosporidium developmental stages were only detected in infected animals in the abomasum region. Histopathological changes were characterized by dilatation and epithelial metaplasia of infected gastric glands with no significant inflammatory responses in the lamina propria. 相似文献
8.
Techakumphu M Promdireg A Phutikanit N Nachiengmai A Thongjan S 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2004,66(8):973-975
The objective of the experiment was to study oocyte recovery by transvaginal, ultrasound-guided, follicle aspiration, from Thai swamp buffalo using different vacuum pressures. Six adult buffalo heifers, aged 2.5-3.0 yrs were treated with a total dose of 280 mg FSH, given twice a day in a divided doses over a three day period (60/60 mg, 50/50 mg, 30/30 mg) at d7 after progesterone implant. Three vacuum pressures were used; 100 (n=12), 80 (n=12) and 60 mmHg (n=12) and all of the pressures were performed in each animal. The animals were treated repeatedly and collection took place using 2 sets of each pressure every 2 months, giving a total of 36 collections from each animal. The oocyte recovery rates from each pressure were 81.2% (69/85) 79.1% (53/67) and 90.3% (93/103) for 100, 80 and 60 mmHg respectively. The number of oocytes collected per donor were 5.33 +/- 3.27, 4.42 +/- 2.71 and 7.75 +/- 4.31 respectively. The quality of the oocytes did not improved with the lower vacuum pressure. In conclusion, the application of FSH pretreatment improves the yield of oocytes from Thai, swamp buffalo heifers after gonadotropin treatment when using the vacuum pressures between 60-100 mmHg. 相似文献
9.
Sak B Kvác M Petrzelková K Kvetonová D Pomajbíková K Mulama M Kiyang J Modrý D 《Folia parasitologica》2011,58(2):81-86
Abstract: Two hundred and seventeen captive great apes (150 chimpanzees, Pan troglodytes; 14 bonobos, Pan paniscus; 53 western gorillas, Gorilla gorilla) and 20 personnel from thirteen European zoos and two African sanctuaries were sampled and examined in order to determine the occurrence ofEnterocytozoon bieneusi and species of Encephalitozoon in faecal specimens and to compare the epidemiological situation between zoos and sanctuaries. Microsporidia were detected at all sampling sites. Sequence analyses of ITS amplicons generated by using microsporidia-specific primers determined the presence ofmicrosporidia in 87 samples including 13 humans; since two cases of simultaneous occurrence of Encephalitozoon cuniculi and Enterocytozoon bieneusi were identified, 89 full-length ITS sequences were obtained, namely 78 Encephalitozoon cuniculi genotype I, five E. cuniculi genotype II, two E. hellem 1A and four Enterocytozoon bieneusi. No Encephalitozoon intestinalis-positive samples were identified. This is the first report of Encephalitozoon species and Enterocytozoon bieneusi genotypes in captive great apes kept under various conditions and the first record of natural infection with E. hellem in great apes. A comparison of zoos and sanctuaries showed a significantly higher prevalence of microsporidia in sanctuaries (P<0.001), raising a question about the factors affecting the occurrence of microsporidia in epidemiologically and sanitarily comparable types of facilities. 相似文献
10.
Two species of Cryptosporidium are commonly identified in pigs: Cryptosporidium suis and Cryptosporidium pig genotype II. Detection of Cryptosporidium spp. is routinely based on molecular methods such as polymerase chain reaction (PCR) and subsequent restriction fragment length polymorphism (RFLP) or gene sequencing. However, most of these methods are hampered by low sensitivity to mixed infections. As a solution of this problem, novel species-specific primers were designed and tested in the present study. Sensitivity of our primers was identical to genus-specific primers, but more (1:48) mixed infections were detected using these species-specific primers on 477 DNA samples originating from naturally infected pigs of different age categories. Our results show differences in age-dependent susceptibility of pigs to the infection. Whereas C. suis was found in all tested categories of pigs (1-12 week of age and sows), Cryptosporidium pig genotype II was recorded only in animals older than 6 week of age. Usage of species-specific primers could help to better the understanding of epidemiology of pig specific Cryptosporidium spp. and its occurrence, which, on the basis of our results, is underestimated. 相似文献