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21.
Recombinant-Feline Interferon-Omega (rFeIFN-ω) is an immune-modulator licensed for use subcutaneously in Feline Immunodeficiency virus (FIV) therapy. Despite oral protocols have been suggested, little is known about such use in FIV-infected cats. This study aimed to evaluate the clinical improvement, laboratory findings, concurrent viral excretion and acute phase proteins (APPs) in naturally FIV-infected cats under oral rFeIFN-ω therapy (0.1 MU/cat rFeIFN-ω PO, SID, 90 days). 11 FIV-positive cats were treated with oral rFeIFN-ω (PO Group). Results were compared to previous data from 7 FIV-positive cats treated with the subcutaneous licensed protocol (SC Group). Initial clinical scores were similar in both groups. Independently of the protocol, rFeIFN-ω induced a significant clinical improvement of treated cats. Concurrent viral excretion and APP’s variation were not significant in the PO Group. Oral rFeIFN-ω can be an effective alternative therapy for FIV-infected cats, being also an option for treatment follow-up in cats submitted to the licensed protocol.  相似文献   
22.
Haemonchus contortus is the most prevalent nematode in Brazil. The objective of this study was to select 6 populations of H. contortus of known or suspected benzimidazole resistance status and characterize these using quantitative real-time polymerase chain reaction (qPCR) for single nucleotide polymorphisms (SNPs) F200Y, F167Y and E198A in the β-tubulin isotype 1 gene. qPCR was performed using DNA from a pool of 10 adult male H. contortus from a single animal per farm. Faecal egg count reduction test (FECRT) and egg hatch test (EHT) were used to determine the resistance status. Samples were obtained from 6 farms located in 5 counties in the Ceará State: Tauá, Boa Viagem, Quixadá, Santa Quitéria and Solonópole. The inbred-susceptible-Edinburgh (ISE) isolate was used as reference for comparative purposes in the qPCR. Benzimidazole resistance was detected by FECRT on all farms with efficacy values ranging from 0 to 51%. EC50 values as determined by EHT were all above 1.49 μg/ml. High frequencies of the resistant SNPs F200Y and F167Y alleles were detected but no resistance was detected at SNP E198A. Our results suggest that the SNPs F167Y and F200Y are both important for benzimidazole resistance in the studied populations.  相似文献   
23.
Choroid plexus papilloma (CPP) is a rare, benign, intracranial neoplasm. The present report described a choroid plexus papilloma of the fourth ventricle with unusual proliferative reaction of ependymal/subependymal cells in a stallion. A single, soft neoformation, red-gray in color, with an irregular surface, resembling a cauliflower, expanding from the fourth ventricle to the cerebellar peduncles was observed. Microscopically, the neoformation was composed of a single layer of simple cuboidal to columnar epithelium with a well-vascularized papillary-arboriform pattern. Multifocal subependymal aggregates forming rosettes were observed near the mesencephalic aqueduct (MA). Glial-fibrillary-acidic-protein (GFAP) was markedly positive only in the neuropil adjacent to the proliferative areas of the MA. Ependymal/subependymal reactions secondary to CPP have never been described in equine or human neuropathology. The capabilities of ependymal cells to regenerate and eventually proliferate are controversial and unclear and, thus, require additional investigation to understand the adaptive mechanisms of this rare pathogenic condition.  相似文献   
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Identifying the action of natural selection from patterns of standing genetic variation has long been of interest to the population genetic community. Thanks to the availability of large single‐nucleotide polymorphism (SNP) data sets for many species and of high‐throughput SNP genotyping methods, whole‐genomic surveys to detect selective sweeps are now possible. Knowing the ancestral allele increases the power to detect selection. We present here a comparative genomic approach to determine the putative ancestral allele of bovine SNPs deposited in public databases. We analysed 19 551 488 SNPs and identified the putative ancestral allele for 14 339 107 SNPs. Our predicted ancestral alleles were in agreement with ancestral alleles detected by genotyping outgroup species for 97% SNPs from the BovineSNP50 BeadChip. This comparison indicates that our comparative genomic‐based approach to identify putative ancestral alleles is reliable.  相似文献   
26.
A possible role of breeding activities in the composition of the microbial population in stallions' external genitalia (EG) and the relationship between micro‐organisms colonizing the skin of the abdomen and the ones colonizing the EG have not been studied. In experiment 1, EG microbiological samples were collected from 41 stallions used for both natural cover and semen collection (BST) and from 18 non‐breeding stallions (NBST). A higher (p < 0.05) frequency of isolation of potentially pathogenic species was found for BST. Age did not influence number of micro‐organism species isolated both in BST and NBST. In experiment 2, the microbial content of the EG and semen was compared in 23 BST. Most micro‐organisms isolated from the EG were present in semen, albeit with a numerically lower prevalence. In 7 stallions, six microbial species isolated from semen were absent from the EG cultures, suggesting contamination by the operator. In experiment 3, a numerically higher number of micro‐organism species was isolated from the EG of 31 stallions, than from their skin of the ventral abdomen in contact with the penis or from the skin of the thorax. With the sole exception of Escherichia coli, potentially pathogenic bacteria were only isolated from the EG but not from the skin. Results suggest that breeding activity increased the number of species colonizing the EG; most species isolated from the EG were also found in semen even if with a lower frequency, and additional semen contamination seemed to occur during its manipulation. Many micro‐organism species of the skin were also isolated from the penis, but independently of being or not in contact with the penis, skin did not seem to provide an adequate environment for the growth of potentially pathogenic bacteria that were isolated from EG, with the sole exception for E. coli.  相似文献   
27.
The presence of the non-indigenous species, the black-pygmy mussel Xenostrobus securis, is reported here for the first time in an intense shellfish farming area off Galicia (NW Spain). Very high concentrations of this mytilid bivalve have colonized estuarine waters located at the inner part of the Ria de Vigo. The invasive role of X. securis is discussed in the context of the wide ecological tolerance of the species and the recent finding of settlements of this species on numerous colonies of the economically-important blue mussel Mytilus galloprovincialis. The mode of introduction of the black-pygmy mussel is also discussed in relation to human management activities.  相似文献   
28.
The molecular cloning of the sea bass FSH receptor gene is reported. Expression analysis revealed that this gene is exclusively expressed in gonadal tissues.  相似文献   
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  • 1 A history of marine research on the Azores is outlined. Until two decades ago most oceanic and littoral marine studies had been carried out by foreign scientists. Studies by Azorean scientists started to increase in the early 1980s when the University of the Azores was created.
  • 2 Ocean circulation in this part of the Atlantic is described as a background for biogeography and diversity. The picture emerges that Azores is a ?meeting point’? for shallow water marine fauna and flora of different origins.
  • 3 The species composition of one of the best studied groups of organisms, the fish, is compared between locations in the northeastern Atlantic. The work on fish is also compared with other well studied groups (algae and hydroids) to highlight the interest of the Azores as a natural biogeographical experiment.
  • 4 Studies of marine resources began less than two decades ago. The development of demersal fisheries is described focusing on the switch from small-scale artisanal fishing to more commercial fisheries.
  • 5 Conservation of species and legislation in force for molluscs, crustaceans, fishes, marine turtles, seabirds and marine mammals are summarized.
  • 6 Protected marine areas already designated are defined, as well as new areas recommended.
  • 7 The paper concludes with a discussion of current threats and future management strategies.
  相似文献   
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