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702. Observations on non-random distribution of spores of Henneguya spp. (Cnidaria: Myxosporea: Myxobolidae) within plasmodia
- Creator:
- Eiras, Jorge C. , Cruz, Manuel , Cruz, Cristina , Saraiva, Aurélia , Adriano, Edson A., Székely, Csaba , and Molnár, Kálmán
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Myxozoa, fish, parasites, spores arrangement, and motility
- Language:
- English
- Description:
- Species of the cnidarian genus Henneguya Thélohan, 1892 (Myxosporea: Myxobolidae) are histozoic parasites commonly found in freshwater and, more rarely, in marine fish. The development of these parasites in fish tissues includes the formation of plasmodia within which occurs the sporogony originating spores with two caudal processes, which are usually randomly distributed within the plasmodia. In this report the authors present some cases of non-random distribution of the spores of six species of Henneguya within their plasmodia. Two different patterns of non-random distribution were found based on a literature survey. These patterns and their origin are discussed. Apparently this non-random distribution of the spores is due to both internal and external factors.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
703. Observations on sporulation of Eimeria bovis (Apicomplexa: Eimeriidae) from the European bison Bison bonasus: effect of temperature and potassium dichromate solution
- Creator:
- Pyziel, Anna M and Demiaszkiewicz, Aleksander W
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- kokcidie, coccidia, experimental development of oocysts, wisent, Bialowieza Primeval Forest, 2, and 59
- Language:
- English
- Description:
- The present study was designed to determine the influence of temperature and the addition of potassium dichromate solution (K2Cr2O7) on the efficiency of sporulation of Eimeria bovis (Zublin, 1908), a coccidian species most commonly diagnosed in European bison Bison bonasus (Linnaeus). Sporulation under conventional conditions (2.5% dichromate solution, 23 °C) was completed on the fourth day of incubation (control), whereas the oocyst development took two days more at the temperature of 18 °C, and two days less at 28 °C. Additionally, experimental sporulation of E. bovis at the temperature of 23 °C in the environment of sterilised tap water (without any preservation) took 9 days more compared to control. Finally, oocyst development took 16 weeks when the faces were stored in the refrigerator (3-5 °C) without any special additives. Overall, our results indicate that K2Cr2O7, besides the temperature, plays a crucial role in the process of sporulation of oocysts under laboratory conditions, as the longest delay in sporogony was observed when the faeces were stored without any other additives in the temperature of the refrigerator., Anna M. Pyziel, Aleksander W. Demiaszkiewicz., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
704. Occurrence and diversity of anaerobic gut fungi in wild forest elephants and buffaloes inhabiting two separated forest ecosystems in Central West Africa
- Creator:
- Schulz, Doreen, Pšenková-Profousová, Ilona, Červená, Barbora, Procter, Miranda, Fuh Neba, Terence, Modrý, David, Petrželková, Klára J., and Qablan, Moneeb A.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- gut microbiome, mycobiome, wild herbivores, and Neocallimastigomycetes
- Language:
- English
- Description:
- Anaerobic gut fungi of the class Neocallimastigomycetes are of great importance for herbivorous animals. Their immediate colonization and mechanical breakdown of plant particles pave the way for highly efficient enzymatic fermentation of complex plant polysaccharides. Neocallimastigomycetes are found in a variety of herbivores, yet so far studies almost exclusively investigated domestic or captive animals. Here, the occurrence and diversity of Neocallimastigomycetes in two different populations of sympatric, wild African forest elephants and forest buffaloes were determined. In both hosts together, a total of 16 species-equivalent Operational Taxonomic Units (OTUs) (0.05 cut-off level) were generated. Buffaloes harboured four and elephants five anaerobic fungi genera or genus-equivalent taxa, respectively, with four genera occurring in both hosts. In elephants the majority of gut fungi group within a cluster of yet unknown Neocallimastigomycetes. Similarly, some anaerobic fungi found in buffaloes form a genus-equivalent cluster with likewise undescribed gut fungi. Sequences grouping in these two clusters could potentially qualify as representatives of new anaerobic fungi genera. Further, three sequences have not yet been encountered in any study and cannot be assigned to any genus or genus-equivalent Neocallimastigomycetes taxon. Whether these sequences also represent putative new lineages needs further investigation.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
705. Occurrence and genetic diversity of Cryptosporidium spp. in wild foxes, wolves, jackals, and bears in central Europe
- Creator:
- Kváč, Martin, Myšková, Eva, Holubová, Nikola, Kellnerová, Klára, Kicia, Marta, Rajský, Dušan, McEvoy, John, Feng, Yaoyu, Hanzal, Vladimír, and Sak, Bohumil
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- PCR, carnivores, genotyping, SSU, gp60, microscopy, Czech Republic, Poland, and Slovakia
- Language:
- English
- Description:
- Parasites of the genus Cryptosporidium Tyzzer, 1910 are one of the most common protistan parasites of vertebrates. Faecal samples from 179 red foxes (Vulpes vulpes [Linnaeus]), 100 grey wolves (Canis lupus Linnaeus), 11 golden jackals (Canis aureus Linnaeus), and 63 brown bears (Ursus arctos Linnaeus) were collected in the Czech Republic, Poland and Slovakia. Samples were examined for the presence of Cryptosporidium spp. using microscopy and PCR/sequence analysis. Phylogenetic analysis based on the small subunit ribosomal RNA (SSU), actin and 60-kDa glycoprotein (gp60) genes using the maximum likelihood method revealed the presence of Cryptosporidium tyzzeri Ren, Zhao, Zhang, Ning, Jian et al., 2012 (n = 1) and C. andersoni Lindsay, Upton, Owens, Morgan, Mead et Blackburn, 2000 (n = 2) in red foxes, C. canis Fayer, Trout, Xiao, Morgan, Lai et Dubey, 2001 (n = 2) and C. ubiquitum Fayer, Santín et Macarisin, 2010 (n = 2) in grey wolves, and C. galli Pavlásek, 1999 in brown bears (n = 1) and red foxes (n = 1). Subtyping of isolates of C. ubiquitum and C. tyzzeri based on sequence analysis of gp60 showed that they belong to the XIId and IXa families, respectively. The presence of specific DNA of C. tyzzeri, C. andersoni and C. galli, which primarily infect the prey of carnivores, is probably the result of their passage through the gastrointestinal tract of the carnivores. Finding C. ubiquitum XIId in wolves may mean broadening the host spectrum of this subtype, but it remains possible this is the result of infected prey passing through the wolf - in this case deer, which is a common host of this parasite. The dog genotype of C. canis was reported for the first time in wolves.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
706. On the role of (and threat to) natural history museums in mammal conservation: an African small mammal perspective
- Creator:
- Ferguson, Adam W.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- IUCN Red List, voucher specimen, Africa, next-generation (holistic) collecting, and research ethics
- Language:
- English
- Description:
- The global environment is faced with growing threats from anthropogenic disturbance, propelling the Earth into a 6th mass extinction. For the world's mammals, this is reflected in the fact that 25% of species are threatened with some risk of extinction. During this time of species loss and environmental alteration, the world's natural history museums (NHMs) are uniquely poised to provide novel insight into many aspects of conservation. This review seeks to provide evidence of the importance of NHMs to mammal conservation, how arguments against continued collecting of physical voucher specimens is counterproductive to these efforts, and to identify additional threats to collecting with a particular focus on small mammals across Africa. NHMs contribute unique data for assessing mammal species conservation status through the International Union for Conservation of Nature's (IUCN) Red List of Threatened species. However, NHMs' contributions to mammal conservation go well beyond supporting the IUCN Red List, with studies addressing topics such as human impacts, climate change, genetic diversity, disease, physiology, and biodiversity education. Increasing and diverse challenges, both domestic and international, highlight the growing threats facing NHMs, especially in regards to the issue of lethally sampling individuals for the purpose of creating voucher specimens. Such arguments are counterproductive to conservation efforts and tend to reflect the moral opposition of individual researchers than a true threat to conservation. The need for continued collecting of holistic specimens of all taxa across space and time could not be more urgent, especially for underexplored biodiversity hotspots facing extreme threats such as the Afrotropics.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
707. One step closer to understanding the ecology of Cameraria ohridella (Lepidoptera: Gracillariidae): the effects of light conditions
- Creator:
- Jagiełło, Radosław , Baraniak, Edward , Guzicka, Marzenna , Karolewski, Piotr , Łukowski, Adrian , and Giertych, Marian Jędrzej
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Lepidoptera, Gracillariidae, Cameraria ohridella, Aesculus hippocastanum, light conditions, herbivore, leaf-miner, oocytes, phenolics oxidative capacity, and plant-insect interactions
- Language:
- English
- Description:
- Horse chestnut leaf miner (Cameraria ohridella) has achieved ecological success by colonizing the entire European range of its primary host, horse chestnut (Aesculus hippocastanum). This insect has attracted the attention of scientists, but its ecology is poorly understood. Here, we investigated the effects of varying degrees of light availability on the leaf morphology of horse chestnut saplings and the performance of C. ohridella. A pot experiment under greenhouse conditions was performed in which the photosynthetic photon flux density (PPFD) was reduced from full light by 50% (high light - HL) or 80% (low light - LL). Insect performance parameters were quantified (i.e., pupal mass, efficiency of conversion of utilised leaf tissue (ECU) and potential fecundity). Compared with HL leaflets those from LL were characterised by higher contents of nitrogen and water but lower total phenolics. The oxidative capacity of phenolics (at pH ≈ 10, common in the lepidopteran gut) was low and did not differ in the two treatments. Compared with those collected from HL leaves, the mines of those collected from leaves of plants grown under LL conditions were larger in area but the leaf mass utilized by larvae was similar. Pupae were heavier in LL than in HL conditions, and ECU was higher in LL. The potential fecundity of females was not sensitive for experimental treatment. We conclude that (1) reduced light had a strong beneficial effect on the performance of C. ohridella and (2) phenolics in A. hippocastanum leaf tissues are a poor defence against this herbivore.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
708. Optimal wire myography normalization for the rat dorsal penile, internal pudendal and internal iliac arteries
- Creator:
- Azeez, Tooyib A., Andrade, Manuella R., and La Favor, Justin D.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- normalization procedure, optimal initial tension, myograph, pre-penile arteries, and erectile dysfunction
- Language:
- English
- Description:
- In functional arterial studies using wire myography, the determination of a vessel’s standardized normalization factor (factor k) is an essential step to ensure optimal contraction and relaxation by the arteries when stimulated with their respective vasoactive agents and to obtain reproducible results. The optimal factor k for several arteries have been determined, however, the optimal initial tension and factor k for the arteries involved in erection remains unknown. Hence, in the present study we set out to determine the optimal factor k for the internal iliac artery, proximal and distal internal pudendal artery (IPA), and dorsal penile artery. After isolating, harvesting, and mounting the arteries from male Sprague-Dawley rats on a multi wire myograph, we tested arterial responsivity to high K+-stimulation when the factor k was set at 0.7, 0.8, 0.85, 0.9, 0.95, 1.0, 1.1, and 1.2 to determine the factor k setting that results in the greatest K+-induced active force production for each vessel type. The data showed the optimal factor k is 0.90-0.95 for the dorsal penile, distal internal pudendal and internal iliac arteries while it is 0.85-0.90 for proximal internal pudendal artery. These optimal values corresponded to initial passive tension settings of 1.10±0.16 - 1.46±0.23, 1.28±0.20 - 1.69±0.34, 1.03±0.27 - 1.33±0.31, and 1.33±0.31 - 1.77±0.43 mN/mm for the dorsal penile, distal IP, proximal IP, and internal iliac arteries, respectively.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
709. Order and timing of home ownership and fertility decisions in Australia
- Creator:
- Spallek, Melanie and Haynes, Michele
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- event history analysis, multi-process, life course, home ownership, and fertility.
- Language:
- English
- Description:
- The birth of a child and transition into home ownership are markers of progression along a life course. Research shows that pathways to home ownership have become more diverse and deviate from the traditional pathway which was characterised by marriage followed by the birth of a child before entering home ownership. This study investigates the timing and order of the two interrelated events of birth of a child and the transition to home ownership in Australia. Using the Household, Income and Labour Dynamics in Australia panel survey, we apply a multi-process event history analysis for describing the timing of each event following the formation of a cohabiting relationship. The results suggest that the likelihood of birth increases with prior home ownership attainment but as time passes following the purchase of a home, the likelihood of birth decreases, similarly, the likelihood of home ownership attainment decreased with time following birth.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
710. Osteological description of Indian lepidophagous catfish Pachypterus khavalchor (Siluriformes: Horabagridae) from the Western Ghats of India
- Creator:
- Pise, Manoj, Gosavi, Sachin M., Gorule, Pankaj A., Verma, Chandani R., Kharat, Sanjay S., Kalous, Lukáš, and Kumkar, Pradeep
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- skeletal morphology, lepidophagy, sexual dimorphism, and systematics
- Language:
- English
- Description:
- The present study provides a comprehensive osteological description of Pachypterus khavalchor from the family Horabagridae. Nine individuals of P. khavalchor representing both males and females collected from the type locality were cleared and double-stained to provide a description of osteological characteristics. The presence of an almost straight dorsal roof to the cranium, a long and protruding premaxilla with numerous rows of tiny, villiform teeth, a spoon-like lower jaw with villiform teeth projecting outward, and five long and ossified ceratobranchials, with the 5th ceratobranchial containing a set of 80 to 90 conical teeth, sheds light on the ecomorphological adaptation in P. khavalchor that may have led to the evolution of lepidophagy. Furthermore, a slight difference in the structure of the complex hypurapophysis was observed between males and females. The information on the osteology of the Khavalchor catfish forms a baseline for taxonomic research of the entire Horabagridae family comprising four genera with ten species distributed in Asia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public