Chromosomes of <i>Poecilia mexicana mexicana, </i>one the bisexual species involved in hybrid origin unisexual teleost fish <i>P</i>. <i>formosa, </i>were analyzed by several staining techniques. Sex-specific, differential heterochromatin, found other congeneric species, was not observed <i>m</i>. <i>mexicana</i>. Nucleolar organizer regions were polymorphic among individual specimens within a given population sample. A single...

The anatomy and the histology of digestive tract young adult sea‐bream is described from studies using light scanning electron microscopy. dentition in juvenile (25–30 mm long) comprises all canine‐like teeth, to which plate teeth transition elements are added adult. oesophagus shows a multi‐layered mucosa upper part, single‐layered regions lower part. formed by epithelial cells, mucus‐secreting cells rich with eosinophilic granules. Y‐shaped stomach, clearly distinguishable, has columnar...

We present a database containing cytogenetic data of Neotropical actinopterygian fishes from Venezuela obtained in single laboratory for the first time. The results this study include 103 species belonging to 74 genera assigned 45 families and 17 out 40 teleost orders. In group marine fishes, modal diploid number was 2n=48 represented 60% studied species, while freshwater fish complement 2n=54, 21.21 % species. average chromosomes mean FN were statistically higher than fish. degree...

Brown trout is considered a complex of incipient species, including several phylogenetic lineages, whose natural distribution in the Mediterranean area has been altered, since beginning 1900s, by massive introductions domestic strains Atlantic origin to support fisheries. Introduced naturalize new suitable environments and extensively hybridize with native populations. Here, we characterized putatively neutral adaptive genetic variability population structure brown from six river catchments...

Glass eels (Anguilla anguilla, L. 1758) caught during ascent at the mouth of River Tiber were kept in aquaria with freshwater and full strength salinity (35 %) for four months. Morphological features glass capture after months experimental rearin are described. The structure gut, an important osmoregulatory organ, observed seawater rearing suggests that they undergo irreversible process adaptation to freshwater, despite fact survival seawater.

Abstract An in vitro study assessing the kinetics of drug release from antibiotic–fibrin seal compounds and antibacterial efficacy delivered has been performed. Antibiotic sensitivity amount released was measured by means agar diffusion test. Standard experimental curves were established for each antibiotic bacterial test order to evaluate quantities during 24 h period. The reconstitution lyophilized human fibrin with an aqueous solution containing resulted only minor modification clotting...

Ancistrus Kner, 1854, is the most diverse genus among Ancistrini (Loricariidae) with 70 valid species showing a wide geographic distribution and great taxonomic systematic complexity. To date, about 40 taxa have been karyotyped, all from Brazil Argentina, but statistic uncertain because 30 of these reports deal samples that not yet identified at level. This study provides first cytogenetic description bristlenose catfish, clementinae Rendahl, 1937, endemic to Ecuador, aiming verify whether...

Abstract Franchini, P., Sola, L., Crosetti, D., Milana, V., and Rossi, A. R. 2012. Low levels of population genetic structure in the gilthead sea bream, Sparus aurata, along coast Italy. – ICES Journal Marine Science, 69: 41–50. The is a coastal, commercially important fish. Contrasting results concerning species at different geographic scales have been reported. Here, an investigation made into S. aurata Italy, using samples analysed previously material from new sampling sites (12)...

A rat model of chronic staphylococcal osteomyelitis was developed. Fibrin glue (5 microliters) and Staphylococcus aureus (2 x 10(6) CFU/5 were inoculated into the proximal metaphysis tibia. The rats killed at intervals between 1 6 months, tibias removed. Induced lesions evaluated by radiographic, macroscopic, histological examinations bacterial counts. Roentgenograms revealed in more than 90% tibias. Gross bone pathology skeletal deformation, new formation, abscesses, draining skin fistulas...

Leuciscine fishes represent an important component of freshwater ichthyofauna endemic to northern Mediterranean areas. This lineage shows high intra-specific morphological variability and exhibits levels hybridization, two characteristics that contribute systematic uncertainties, misclassification taxa and, potentially, the mismanagement biodiversity. study focused on brook chub, Squalius lucumonis, taxon Central Italy. The taxonomic status this species has long been questioned, a hybrid...

Abstract The development of the fin skeleton has been studied in both wild and hatchery sea bass, Dicentrarchus labrax L., larvae, order to identify define morphofunctional criteria for larval quality assessments. cartilaginous bony skeletal elements larvae were standard length notochord flexure recorded. Fin anomalies present reared whereas they rare or absent specimens from wild. These recognizable very beginning development, indicating that environmental, genetic broodstock management...

Abstract The gilthead seabream, Sparus aurata, represents an important economic resource for Mediterranean aquaculture. In spite of its wide geographic distribution and importance, only recently studies have been carried out on the genetic composition natural populations, which revealed a picture heterogeneous degree differentiation among S. aurata populations. this study allozyme analysis samples from six different collecting sites along Italian Croatian coasts was out, covering area in...

Recent molecular phylogenetic analyses have shown that the Mugil curema Valenciennes, 1836 species complex includes M. incilis Hancock, 1830, thoburni (Jordan & Starks, 1896) and at least four "M. curema" mitochondrial lineages, considered as cryptic species. The cytogenetic data on some representatives of a high diversity. This research reports results white mullet collected in Ecuador. analyzed specimens were molecularly assigned to sp. O, putative present Pacific Ocean showed 2n = 46...

Abstract The extraordinary polymorphism of major histocompatibility complex (MHC) genes is considered a paradigm pathogen‐mediated balancing selection, although empirical evidence still scarce. Furthermore, the relative contribution selection to shape MHC population structure and diversity, compared that neutral forces, as well its interaction with other evolutionary processes such hybridization, remains largely unclear. To investigate these issues, we analyzed adaptive (MHC‐DAB gene) (11...

This study delves deeper into the impact of environmental temperature variations on nervous system in teleost fish. Previous research has demonstrated that exposing adult zebrafish (Danio rerio) to 18 °C and 34 for 4 or 21 days induces behavioural changes compared fish kept at a control 26 °C, suggesting alterations system. Subsequent studies revealed these conditions also modify brain protein expression, indicating potential neurotoxic effects. The primary aim this work was investigate...

This study presents a cytogenetic analysis of the genus Dicentrarchus , represented by two species, D. labrax and punctatus . The karyotypes are very similar, even after staining with different techniques. Both species show 48 subtelocentric acrocentric chromosomes, gradually decreasing in size. One pair small size chromosomes has heteropycnotic heteromorphtc short arms longer These C‐ Ag‐positive, i.e. nucleolar organizer regions, NORs, located there. Constitutive heterochromatin is also...