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Migration dynamics of incoming eels in Belgium via Lixhe in the Meuse River were investigated using two fish passes with different configurations—net traps and automatic detection stations—as tools to distinguish resident and migrating eels. From April to September 2013, 435 eels (P50 length, 403 mm; range, 196–836 mm) were caught (daily maxima catch, 90 eels per day), 90% between 13 June and 1 August (50 days) and P50 on 19 July. Eels migrated mostly at 19–26 °C (P50, 24.4 °C), river discharge 65–314 m3 s−1 (P50, 84 m3 s−1), during the dark at 00:00–05:00 h and during both the waxing and waning phases of moonlight. From 396 eels tagged and released 0.3 km downstream of the Lixhe dam, 6.8% of them were recaptured, and 37.4% were detected. Migration flux was estimated at 7184 eels (0.863 t) using the mark-recapture method and decreased to 1156 eels (0.139 t) using automatic transponder detection. Most eels probably migrated through a sluice located downstream of Lixhe to reach the upper Meuse via the Albert Canal. Eels moved almost independently to the configuration of the fish passes and their location, but most eels displayed fidelity to the fish pass where they were captured. Migrant eels showed a wide range of size and life stages, with a higher proportion of eels (80%) belonging to the yellow eel stage. A lower proportion of eels (6%) had a larger size and presented an advanced continental silvering process corresponding to the migrating stage before their transatlantic migration. Copyright © 2016 John Wiley & Sons, Ltd.

The egg-release, mating, courting and aggressive acts for the spawning behaviour as well as the survival rates after spawning at stages of eyed embryos, viable hatchlings, and larvae to dry food consumption for the mating success were studied in cultured silver bream Blicca bjoerkna × rudd Scardinius erythrophthalmus hybrids at their first sexual maturity. Experiments were conducted in experimental environments simulating natural reproductive conditions of the parental species. Spawning behaviour was analysed over 1 day from 8.00 to 18.00 hours using a remote-controlled video. Mating success was assessed from eggs and hatched embryos collected on the spawning ground. The results showed that these hybrids exhibited all the reproductive behaviours of the parental species with significantly more courtship than mating. Each egg-release act was accompanied by mating behaviour, involving all the experimental males. A surprising aggressive behaviour was observed in one male which attacked all other experimental fish. Successful mating resulted in the presence of fertilized eggs, the production of hatched embryos in experiments, and the survival of larvae at the dry food consumption stage. However, the low viable hatchling rate observed could indicate a very low chance of survival for these hybrids in rivers in which the occurrence of post-F1 individuals may be more possible by backcrossing.

Aspects of the reproductive biology and population structure of Labeo senegalensis were investigated in the Ouémé River between April 2005 and March 2006. Reproductive strategy was investigated using gonadosomatic index, ovarian structure and fecundity. Average size-at-first-maturity (L50) was estimated at 29 cm TL for females and 25.7 cm TL for males. The average sex ratio (1:0.96) was not significantly different from unity. Oocyte diameter frequency distribution suggests synchronous development with a single total spawning. Absolute fecundity ranged between 12 948 and 74 832 eggs. Labeo senegalensis is a highly fecund fish that presents a seasonal cycle of reproduction from May to October during the rainy season.African Journal of Aquatic Science 2010, 35(1): 81–85

Hybridization success at early developmental stages and larval resistance to osmotic, thermal and fasting tests in roach Rutilus rutilus, silver bream Blicca bjoerkna, common bream Abramis brama and their F1 hybrids were investigated. Results revealed that hybrid survival rates were similar to parents. At the eyed embryo stage, however, a maternal effect was observed as a general trend during hatchling and larval stages. After these stages, hybrids displayed a higher survival rate than their parents. Under stress tests, no survival was observed after 40 min for osmotic and thermal shocks and after 24 days for the prolonged fasting test in these species and their F1 hybrids. The median survivals of hybrids were intermediate between the two parents. For total mortality, hybrids were also affected by a maternal effect but to the advantage of the hybrids.

Mating patterns among first-generation hybrids of the roach, Rutilus rutilus, and the silver bream, Blicca bjoerkna, between hybrids or with parent-species males, have been investigated under experimental reproduction conditions. The results reveal that the level of sexual activity of these hybrids is high. Hybrid females mated simultaneously and successively with all types of male, resulting in fertilised eggs. Individual participation of roach males in mating was never observed, however.

Artisanal fishery gill-net catches of the catfish Schilbe intermedius were studied in the Okpara and Zou tributaries of the Oueme River, Benin in 1999 and 2000. The largest fish caught at the Toue and Kpassa stations measured 26.2cm and 24.5cm (TL) respectively. The success of artisanal fishing for schilbeids varied during the day, with the highest fish catches being recorded at approximately 22h00 and at 07h00 and the lowest between 13h15 and 16h15. The monthly production at Kpassa varied between 9.0g and 900.0g (average 206.3g) and between 3.3g and 17 320g (average 2 603.4g) at Toue. The monthly production fluctuated considerably. At the two stations, fewer fish were caught each month in the second year than in the same months in the first year. Nets of between 10 and 15mm stretch mesh were the most efficient. Above 15mm, gill-net fishing became less effective. Large fish were often taken with gill-nets of 20–30mm stretch mesh. Beyond these mesh sizes, the gill-net yield and catch decreased.

To evaluate the impact of PCBs on a wild population of a regressing fish species, we have measured the levels of these toxicants in common barbel (Barbus barbus) from the Belgian part of the river Meuse. We have expressed these levels in terms of the most suitable composition of commercial PCB mixture (Aroclor 1254 and 1260 20/80; v/v), and related them to hepatic xenobiotic-metabolising enzyme activities and to hepatocyte ultrastructure.

Captive breeding and the release of captive-bred individuals into the wild are among the techniques used for the conservation of rare and endangered fish species. After a brief description of the methods of captive breeding and the establishment of breeding stocks, this paper provides examples of the application of these techniques to endemic fish species of arid regions in south-western USA and examines some current cases and the future possibilities for their use in the Mediterranean region. Special attention is given to the analysis of the strict constraints imposed on fish breeding for conservation purposes, in which the aim is to produce fish with all the morphological, behavioural and genetic characteristics of the taxa to be conserved, and which are capable of effectively adapting to the natural environment when introduced. In terms of genetic management of captive populations, the fundamental problems which are faced involve the categorization of the species-resources to be conserved (identification of cases of inter- and intra-specific introgression), the establishment of founder stocks that contain the maximum genetic diversity depending on the genetic structure of the species (strong intra- or interpopulation variability), and the retention of genetic variability during captive breeding (the need to reduce to the minimum the phenomena of genetic drift, inbreeding and unintentional selection of non-adapted genotypes). Because of these difficulties and risks in terms of genetic conservation, captive breeding should remain a temporary safeguard measure, while awaiting the implementation of measures for protecting species in their restored original habitat or translocation to strictly protected substitute habitats. With this aim in view and in conclusion, the paper suggests methods for organizing a critical plan to safeguard the most endangered species or subspecies in the Mediterranean region by captive breeding.

Dans le moyen delta de l’Ouémé au Bénin, les tailles de première maturité et de capture des populations de six espèces de poisson-chat ont été étudiées. Il s’agit de Clarias gariepinus, de C. ebriensis, de Schilbe intermedius, de S. mystus, de Synodontis schall et de S. nigrita. La relation de type sigmoïde entre le pourcentage de maturité sexuelle (P) et la taille (Lt) des poissons a été déterminée d’après le modèle logistique de Dagnelie (1973). L’équation générale de Von Bertalanffy (1938) incorporée au logiciel FISAT II a permis de déterminer les tailles de première capture (Lc50). En général, les mâles maturent à une taille inférieure à celle des femelles. Les tailles à la première maturité (L50) sont supérieures aux tailles de première capture (Lc50). On en déduit une surexploitation des six populations de poissons étudiées qui sont en général pêchées avant la première reproduction. Il serait intéressant que les poissons soient capturés à une plus grande taille (Lc50 > L50)Keywords: Poissons-chats, maturité sexuelle, exploitation, delta de l’Ouém&eacute

Postischaemic reperfusion injury is often attributed to the generation of oxygenated free radicals which may subsequently promote lipid peroxidation in cell membranes. Electron paramagnetic resonance spectroscopy in association with the spin trap molecule α-phenyl- N-tert-butyl-nitrone allowed direct confirmation of lipid free radical production after renal ischaemia-reperfusion in an in vivo rabbit model. A 60-min period of ischaemia followed by reperfusion caused free radical production twofold greater than after 15min of ischaemia. Glutathione and a-tocopherol have been measured in renal tissue, as indirect markers of lipid peroxidation. After 15min of ischaemia followed by 10min of reperfusion, the mean(s.e.m.) glutathione content of the ischaemic kidney was slightly but significantly reduced by 11.9(2.5)% ( P < 0.003). The content of α-tocopherol was unchanged. However, 10min of reperfusion following 60 min of ischaemia led to significant decrease in mean(s.e.m.) content of both glutathione (30.4(3.7)%) (2.23(0.2) versus 3.14(0.18) μmol/g wet tissue, ( P < 0.001) and α-tocopherol (46.1(7.8)%) (0.57(0.10) versus 1.09(0.14) μg/g wet tissue. P < 0.001) when compared to the control kidney. Under these experimental conditions, desferrioxamine (15mg/kg administered intravenously before inducing ischaemia), a drug known to limit free radical production, significantly limited the decrease of α-tocopherol to 20.8(6.4)% (0.83(0.08) versus 1.05(0.04) μg/g wet tissue. P < 0.05), but did not prevent glutathione consumption in the reperfused kidney.

The cardiovascular and respiratory parameters of eight laboratory beagles were measured before and after the simultaneous injection of medetomidine (40 micrograms/kg bw) and ketamine (5 mg/bg bw). This combination produced a significant alteration in cardiovascular function. The heart rate, the stroke volume and cardiac output decreased while the systemic vascular resistance increased. These effects were attributed principally to the alpha 2 agonist compound combined with the moderate stimulatory effect of ketamine. The respiratory parameters were little affected by this protocol.

In this study, relationships between circulating androgens, aggressive behaviour and breeding tubercles in males of common bream Abramis brama were examined in an aquarium environment. The breeding tubercles of fish were counted, the number of attacks was quantified by male status and circulating rates of testosterone and 11-ketotestosterone from blood plasma were analysed using radioimmunoassay procedures. The results revealed that no significant differences were found between circulating testosterone and 11-ketotestosterone in territorial and nonterritorial males. Furthermore, no significant correlations were found between circulating androgens, androgens and aggression, androgens and tubercles and breeding tubercles and aggression in common bream by male status. However, territorial fish displayed a significantly higher level of aggressive behaviour and breeding tubercles than nonterritorial fish. In natural environments, the occurrence of breeding tubercles during the spawning season could contribute to identifying the behavioural status of common bream males.

L\'etude de l\'âge et de la croissance chez Clarias gariepinus a ete realisee dans le delta de l\'Oueme par l\'analyse des structures par tailles et l\'examen de coupes minces dans l\'epine de la nageoire pectorale droite. Les tailles obtenues par retrocalcul aux differents âges ont ete comparees a celles des structures par tailles. La taille moyenne modale chez C. gariepinus se situe entre 25 et 30 cm Lt a la fin de la premiere annee de vie. Les resultats obtenus, couples a une analyse des caracteristiques physico-chimiques et biologiques du milieu, nous revelent l\'apparition de marques d\'arret et/ou de ralentissement de croissance sur les pieces osseuses de l\'espece aux mois de juillet-aout. Les facteurs responsables de l\'inscription des marques sur les pieces sont la diminution du niveau de l\'eau dans le fleuve a l\'etiage (fevrier, mars, avril), le confinement des poissons dans un petit volume d\'eau et la rarete des ressources alimentaires dans le milieu. Keywords : Clarias gariepinus , squelettochronologie, marques de croissance, fleuve Oueme. International Journal of Biological and Chemical Sciences Vol. 2 (2) 2008: pp.157-167

By using alpha-phenyl N-tert-butyl nitrone (PBN) as spin trap molecule and the electron paramagnetic resonance (EPR) technique, we obtained the first direct evidence of in vivo intervention of free radicals during an ischemia (50 minutes) reperfusion phenomenon in kidney of an intact rabbit. An EPR signal (triplet of doublets) characterized by coupling constants aN = 14.75-15 G and aH beta = 2.5-3 G was detected in blood samples. The signal was consistent with a nitroxyl-radical adduct resulting from the spin trapping by PBN of either oxygen-or carbon-centered radicals. Control experiments indicated that the EPR signal was not due to a toxic effect of the spin trap molecule.

In control rabbits, a renal ischemia of 60 min followed by 10 min of reperfusion resulted in an enhanced free radical production in cortical tissue, as assessed by a significant decrease of free glutathione (42%), protein-bound GSH (17%), and vitamin E (49%). In contrast, catalase or glutathione peroxidase activities were not affected by these experimental conditions. Free radical production in this model was also measured directly using electron spin resonance (ESR) spectroscopy associated with a PBN (alpha-phenyl N-tert-butyl-nitrone) spin trap agent in the venous blood arising from the ischemic kidney. The signal consisted of a triplet of doublets. In contrast, no signal could be detected in control blood samples taken prior to inducing ischemia. The burst of free radical production occurred in the early phase after restoration of flow in the kidneys rendered ischemic, as evidenced by a signal of weak intensity which generally appeared within the third minute after reperfusion and progressively increased to form a well-defined asymmetric signal following 10 min of reperfusion. The precise nature of free radicals trapped by the PBN agent remains, however, to be elucidated, but analysis of the coupling constants (aN = 14.5-15 G; a beta H = 2.5-3 G) and asymmetry of the central doublets suggests that the ESR signal may arise from a nitorxy-radical adduct resulting from the spin trapping by PBN of both oxygen- or carbon-centered radicals of lipid origin. As evidenced by both direct and indirect measurements, exchange of rabbit blood immediately after inducing renal ischemia with 30 ml/kg of Diaspirin Crosslinked Hemoglobin (7.5 g/dl in lactated electrolyte) or human serum albumin (7.5 g/dl in lactated electrolyte) did not exacerbate free radical production mediated by an ischemia reperfusion phenomenon, a typical situation found in a resuscitation setting.

The thymi of op/op rats were investigated before and after bone marrow graft. Normal littermates were used as controls. The thymic involution and atrophy in non-treated op/op rats was characterized by the presence of pyknotic thymocytes (apoptosis) and numerous lipid-laden macrophages containing pleiomorphic lysosomes. This thymic atrophy is histologically very similar to the thymic involution induced by glucocorticoids or by stress in normal rats. In treated new born op/op rats, the osteopetrotic process began to be reversed 2 weeks after the graft. The thymus of treated op/op recovered a normal weight and its histology and ultrastructure were quite similar to that of normal littermates. These findings are discussed in relation to the defective macrophage function and cellular immunity impairment reported in osteopetrosis.

Cardiomyoplasty is a wrapping of an electrostimulated latissimus dorsi muscle flap around the heart for substitution and/or reinforcement. The surgical technique for reproducible cardiomyoplasties in the goat model is presented. The methods combine the direction of wrapping (clockwise, counter-clockwise) and the orientation of muscle fibers. A cardiomyoplasty model using right and left latissimus dorsi or left latissimus dorsi and pectoralis major as well as a split muscle technique are illustrated.

Cardiomyoplasty is a new surgical procedure using transformed skeletal muscle to reinforce or substitute for the myocardium. For the purpose of studying surgical technique and investigating basic questions, we have developed a model of reinforcement cardiomyoplasty. Herein, we describe anesthetic management, surgical technique, and the technique for iterative transthoracic biopsies. This model has proven to be valuable in several long-term studies involving more than 30 goats. Preliminary data to ascertain the efficacy of the proposed technique are provided.

7301 Background: Surgery with complete resection of disease remains the optimal treatment for non-small cell lung cancer. We initiated a Phase II study to determine if patients with marginally rese...

A 60 year old woman was referred to our hospital complaining of swelling of the face. Seven years before admission she underwent a thoracotomy for thymoma. The resection of the tumour seemed to be complete, and no adjuvant treatment was given. Five months before admission …

Muscular microcirculation was studied in seven halothane anaesthetised horses in lateral recumbency using a laser Doppler flowmeter. A significant difference between the dependent and the uppermost triceps brachii was recorded. In the dependent muscles, microflow at first decreased and then increased up to the starting value. In the uppermost muscles, a significant rise of the microflow was measured.

Lors d'une etude quantitative des populations de poissons dans un troncon de 9,6 km de l'Ourthe en Belgique, nous avons fait des observations methodologiques concernant l'efficacite de la peche a l'electricite dans une riviere de la Zone a Barbeau (largeur 25-30 m). Nous avons specialement etudie la selectivite en fonction de la taille et de l'espece et l'influence des facteurs habitat (profondeur de l'eau) et debit et de quelques autres facteurs. Les resultats presentes dans cette etude permettent de mieux cerner les problemes poses par le denombrement des populations et communautes de poissons dans les rivieres de moyenne importance.

The cardiovascular function of horses was less depressed during anaesthesia with isoflurane than during anaesthesia with halothane. Muscular microcirculation measured by laser Doppler flowmetry was significantly greater in horses anaesthetised with isoflurane.

Measurements of muscular microcirculation in horses anaesthetised with halothane were performed by laser Doppler flowmetry. Variations of microcirculation in the compressed and uncompressed triceps brachii were measured when horses were positioned in dorsal recumbency after a prolonged period in lateral recumbency. A significant post ischaemic hyperaemia was recorded in horses which developed a post anaesthetic myositis.

The case of a patient with non-obstructive apical hypertrophic cardiomyopathy diagnosed on criteria that are now conventional is reported. This case exhibited two special features: the apical hypertrophic cardiomyopathy was bilateral (i.e. the two ventricles were simultaneously involved) and it was associated with massive mitral and tricuspid valve regurgitation. These two features are frequent in other types of hypertrophic cardiomyopathy, but they have not yet been described in apical hypertrophic cardiomyopathy. They support the concept that there is no definite border between the different types of hypertrophic cardiomyopathy.

The authors report 2 clinical cases of ventricular aneurysm associated with a false tendon attached to the neck of the aneurysm. The first patient had no signs of false tendon before myocardial infarction. When the aneurysm developed, a false tendon was observed at its neck; a second false tendon attached to the first was also seen and appeared to have ruptured. The second patient had a right ventricular aneurysm with the same appearances of false tendon. These two cases suggested that the formation of an aneurysm might project a common muscular band into the ventricular cavity giving electrocardiographic appearances of a false tendon. We observed this association in 6 out of 23 cases of ventricular aneurysms in a prospective study. It is important to recognise this phenomenon and to differentiate it from other echogenic structures (thrombus).

Scanning electron microscopic observations of pulp calcifications in deciduous molars were correlated with microradiographic findings. Numerous spherical calcifications were found in appearance similar to those in the permanent dentition. In a second type, mineralization took the form of diffuse deposits of calcium. The discrete diffuse foci coalesced into large islands of mineralized connective tissue. A third type of calcification was observed in which rhombic crystals were associated in a spherulitic pattern. The exact cause of the crystal formation is unknown. Moreover, as we are aware, the spherulitic calcifications have never been previously reported in this location. The preliminary results indicated that mineralization in the pulp of deciduous molars, takes a variety of forms, suggesting that calcium deposition can occur by different processes.

The authors report the occurrence of an incident during the use of the Servo-ventilator 900 for paediatric anesthesia; it consisted in self-oscillation of the gas column contained in the patient respiratory circuit. After having analysed the incident and outlined the various ways of avoiding it, attention is drawn to the importance of the total circuit volume of the respirator. The respiratory circuit chosen for ventilating children, has a compliance of 1.3 ml/cm H2O.

Arachidonic acid cyclooxygenase metabolites, thromboxane B2 (TXB2), prostaglandin E2 (PGE2) and 6-keto-prostaglandin F1 (6-keto-PGF1) were measured in horses where anaesthesia was maintained with halothane. Two horses suffering from postanaesthetic myositis were compared with four normal horses. TXB2 and PGE2 levels were higher in mixed venous blood drawn from the myopathic horses. An increase of TXB2 and PGE2 levels appeared when myopathic horses were rolled into dorsal recumbency after a prolonged period of lateral recumbency. One hour after the end of anaesthesia, TXB2 had continued to increase whereas PGE2 decreased. By measurements on blood samples drawn from the brachial vein, we have shown that the rising level of TXB2 in mixed venous blood is mainly due to the increase of TXB2 in blood draining the dependent leg. The origin of the rise in PGE2 is not demonstrated in this study. 6-keto-PGF1 did not change during anaesthesia. An explanation of this imbalance between TXB2 and 6-keto-PGF1 production is considered.