Characterization by whole-cell hybridization of bacterial populations associated with shrimp hatchery biofilms

The impact of shrimp larvae development, as well as water and food inputs upon the increase of bacterial populations within the bacterial community of hatchery tank biofilms, was studied. For this study, a total of 68 biofilm samples were collected from concrete tanks at three larvae production times in a commercial shrimp hatchery. Seventeen samples were taken at each larval development stage (Zoea I, Mysis I, postlarvae 1 and postlarvae 16), as well as 37 samples from water, shrimp nauplii and food, introduced into the shrimp hatchery tanks. Culturable and direct bacterial counts were performed and 16S‐rRNA‐targeted oligonucleotide probes were used to quantify the presence of specific bacterial groups. An average of 27–70% of DAPI total cell counts were detected with the EUB338 probe, while the GAM42a probe signal ranged from 1% to 11%. Vibrio‐like bacteria (VLB) counts in TCBS agar ranged from <10 to 10¹ VLB/cm⁻², with a tendency to increase at the last postlarvae stage. The most significant external source of bacteria registered with GAM42a probe and TCBS agar were found in live Artemia nauplii, used as food; nevertheless, biofilms remain with low counts of these groups.     

You cannot conserve a species that has not been found: The case of the marine sponge Axinella polypoides in Liguria,Italy

1. Detailed knowledge about the distribution of species in need of protection is required for the management of Marine Protected Areas, a major tool to reduce marine biodiversity loss. Such knowledge is deficient for most marine invertebrates.
2. Axinella polypoides is a marine sponge included on the list of protected species by the Barcelona Convention (1976) and the Bern Convention (1987). This large and erect species has an important ecological role in habitat forming and benthic–pelagic coupling.
3. Bathymetrical, geographical and ecological data over the last 60 years were collated from publications and reports, together with new surveys to assess the distribution and protection status in Liguria of A. polypoides. It identified a more widespread distribution than previously thought, which points at a general need for dedicated investigations on the occurrence of species that require protection.
4. Bathymetrical distribution was trimodal, with peaks corresponding to different geomorphological settings: coastal cliff bases (around 38 m depth), inner shelf shoals (52 m) and rocks amidst coarse sediment on the outer shelf (79 m). Density was significantly greater at the shallowest depths. The species was mostly found in the coralligenous biocoenosis, in association with other characteristic species or forming a monospecific facies.
5. On (sub)vertical cliffs, A. polypoides often exhibited an unusual cane shape, rather than the typical bushy morphology, thus causing confusion with the congeneric A. cannabina, a more southern species. Records of the latter in the Ligurian Sea therefore need confirmation.
6. Only a minority (22.6%) of A. polypoides records were in Marine Protected Areas, the remainder being located in areas with no current environmental protection plans in place. While the occurrence of this species in MPAs remained stable over the decades, the only quantitative historical data available indicated that populations in non-protected areas were declining owing to anthropogenic impacts (fishing and anchoring).

     

The effects of starving and feeding on Dover sole (Solea solea,Soleidae, Linnaeus, 1758) stress response and early larval development

In the view of an urgent necessity to improve the quantity and the quality of farmed fish species, there is a strong need to improve our basic knowledge on the effects of first feeding during the developmental stages of fish larvae. High mortality, mainly due to food deprivation or inappropriate food quality, has been observed in many larval fish species, but knowledge about the morphological, biochemical and molecular processes related to this topic is still poorly understood. The understanding of the early larval ontogeny as well as the larval nutritional requirements and the molecular and cellular mechanisms elicited by fish larvae during food deprivation and starvation are thus of primary importance. At this regard, this study investigates, in Dover sole larvae, the effects of starvation and starving/re‐feeding procedures at a morphological, histological, biochemical and molecular level. The results evidenced that starved larvae progressively decrease in growth, lipid content, affected their gastrointestinal tract and muscle development and increased cortisol and heat shock protein 70 levels. On the contrary, starved and re‐fed larvae showed, after the restoration of a favourable feeding condition, a compensatory growth. In conclusion, this is the first study analysing through a multidisciplinary approach the effects of food deprivation on the development of an important economic species, the Dover sole.     

Global-scale genetic structure of a cosmopolitan cold-water coral species

• 1. When considering widely distributed marine organisms with low dispersal capabilities, there is often an implication that the distribution of cosmopolitan species is an artefact of taxonomy, constrained by the absence of characters for delimiting either sibling or cryptic species. Few studies have assessed the relationship among populations across the global range of the species' distribution, and the presence of oceanographic barriers that might influence gene flow among populations are underestimated.
• 2. In this study, evolutionary and ecological drivers of connectivity patterns have been inferred among populations of the cold-water coral Desmophyllum dianthus, a common and widespread solitary scleractinian species, whose reproduction strategy and larval dispersal are still poorly unknown.
• 3. The genetic structure of D. dianthus was explored using 30 microsatellites in 347 specimens from 13 localities distributed in the Mediterranean Sea and Atlantic and Pacific Oceans.
• 4. Results clearly reveal genetically differentiated populations in the Northern and Southern Hemispheres (F_ST = 0.16, F_SC = 0.01, F_CT = 0.15, P-values highly significant), and Chilean and New Zealand populations with independent genetic profiles.
• 5. Marine connectivity patterns at different spatial scales are discussed to characterize larval dispersal and gene flow through the Northern and Southern Hemispheres.

     

Sea turtle strandings reveal high anthropogenic mortality in Italian waters

• 1. Spatio‐temporal distribution and anthropogenic mortality factors were investigated in loggerhead turtles (Caretta caretta) found stranded or floating in the waters around Italy. A total of 5938 records for the period 1980–2008 were analysed concerning loggerhead turtles measuring from 3.8 to 97 cm curved carapace length (mean: 48.3 cm).
• 2. Results highlighted the following conservation issues: (i) in the study area, anthropogenic mortality is higher than natural mortality; (ii) interaction with fisheries is by far the most important anthropogenic mortality factor; (iii) longlines are an important mortality factor in the southern areas; (iv) trawlers are the cause of high numbers of dead strandings in the north Adriatic; (v) entanglement in ghost‐gear or in other anthropogenic debris affects high numbers of turtles; and (vi) boat strikes are an important source of mortality in most areas but mostly in the warm seasons.
• 3. Results also indicate that: (vii) the north Adriatic is the area with the highest turtle density; and (viii) the south Adriatic and to a lesser extent the surrounding areas of the north Adriatic and the Ionian, are important developmental areas for loggerhead turtles in the first years of life.
• 4. Italy is in the centre of the Mediterranean Sea and borders major foraging areas for the loggerhead turtles in the region, and these results confirm previous concerns about the level of anthropogenic mortality in Italian waters. Copyright © 2010 John Wiley & Sons, Ltd.

     

Ecological and eco‐social models for the introduction of the abalone Haliotis discus hannai into benthic systems of north‐central Chile: sustainability assessment

• 1. Loop models of ecological and socio‐economic systems were developed to analyse and predict the impact of a possible accidental introduction (escapes) of the abalone Haliotis discus hannai into a benthic community of north‐central Chile.
• 2. Although the ‘new’ ecological system resulting from a successful invasion of abalone would be locally stable, the establishment of a self‐enhanced dynamic of recruits would transform this into an unstable system.
• 3. The harvest of the kelp, Lessonia trabeculata and other macroalgae is not recommended because this destabilizes the system. The harvest of abalone adults is only sustainable if they do not exert a negative effect upon other native invertebrates.
• 4. The eco‐social model showed three important results: (1) if the variables ‘Price’ and ‘Farming’ are in expansion and stationary dynamics, then the models were found unstable; (2) a self‐enhanced dynamic of abalone recruits tends toward instability; and (3) the harvest of the kelp L. trabeculata and other macroalgae would be non‐sustainable.
• 5. Based on our results, the sustainable development of extensive farming of H. discus hannai in the sea would be not reached. If it is done, an intensive monitoring of the community after introduction into the system is strongly recommended. Likewise, the farming of macroalgal species (source of food for abalone) should be promoted in order to avoid harvesting of macroalgae from natural systems.

Copyright © 2006 John Wiley & Sons, Ltd.     

Effect of potato leaf roll virus on autumn potatoes in Israel

Summary In field trials simulating commercial conditions, secondary PLRV infection of autumn-grown potato crops in Israel significantly reduced yield, although symptoms were not perceptible. Plots containing 7.3% PLRV-infected seed showed an increase in yield per plant of 17%, compared with plots with 36.2% infected seed; in plots with only 1.3% infected seed the increase of yield was 21%. In a second experiment, where individual plants were assayed, the yield of PLRV-infected plants of cv. Blanka was only 68.7% of that of PLRV-free plants; corresponding figures for cv. Up-to-Date and Désirée were 79.2 and 58% respectively. PLRV infection was not associated with reduced emergence or with the yield of deformed tubers.

---

Zusammenfassung W?hrend der ersten zwei Monate der im Herbst liegenden Wachstumszeit der Kartoffel (August-Januar) sind in Israel sehr hohe Temperaturen (mittleres Maximum 34,7° C) und hohe Sonneneinstrahlung; anschliessend fallen die Temperaturen und die Lichteinstrahlung stark ab. Unter diesen Bedingungen bleibt die Infektion mit PLRV meist symptomlos und es gibt vom Pflanzenwuchs her keine Anzeichen dafür anzunehmen, dass der Ertrag beeintr?chtigt ist. Imersten Versuch (A) wurden die Ertr?ge von Best?nden verglichen, die die gleiche Pflanzgutgr?sse (Sorte Désirée) hatten, aber von drei Herkünften I, II und III stammten. Der Anteil der PLRV infizierten Knollen in diesen Herkünften betrug 1,3, 7,8 und 32,6% (Abb. 1A). Der durchschnittliche Ertrag pro Parzelle für Herkunft I, II und III lag bei 12,6 kg, 10,0 kg und 7,6 kg (Abb. 1C); die Differenzen zwischen den Herkünften waren signifikant (P<0,05). Der Unterschied zwischen Herkunft I und II gibt vielleicht die unterschiedlichen Auflaufraten wieder (Abb. 1B), aber die Differenz zwischen den Herkünften II und III scheint eine Folge der Virusinfektion zu sein, und ?hnliche Differenzen wurden beim Vergleich des Ertrages pro Pflanze gefunden (Abb. 1D). Diese Annahme wurde im Versuch B best?tigt, in dem der Ertrag PLRV-infizierter Pflanzen mit dem PLRV-freier Pflanzen verglichen wurde. Die Infektion mit PLRV war nicht mit einer verringerten Auflaufrate oder dem Ertrag an deformierten Knollen verbunden, aber infiziertes Pflanzgut der Sorte Blanka ergab nur 68,7% des Ertrages virusfreien Pflanzgutes, Up-to-Date 79,2% und Désirée 58%; die Verluste waren statistisch signifikant (Abb. 3). Diese Ergebnisse lassen annehmen, dass betr?chliche Ertragsverluste durch die Infektion mit PLRV in den im Herbst gepflanzten Kartoffeln eintreten k?nnen, obwohl die Symptome nicht wahrnehmbar sind. Im Hinblick auf den hohen PLRV-Befall in den Herbstbest?nden (Marco, 1981b), kann es von Vorteil sein die im Frühjahr gepflanzten Best?nde vor einer PLRV-Infektion zu schützen, da sie das Pflanzgut für den Herbst stellen.

---

Résumé Pendant les deux premiers mois de végétation des pommes de terre cultivées à l'automne en Israel (Ao?t-Janvier), les températures sont très élevées (moyenne maximale de 34,7°C) et la luminosité très forte. Puis les températures et l'intensité lumineuse diminuent rapidement. Sous de telles conditions, la contamination par le virus de l'enroulement est généralement existante mais sans l'apparition de sympt?mes; rien ne permet donc d'indiquer en végétation que le rendement est affecté. Dans une première expérience (A), le rendement est comparé pour trois cultures obtenues à partir de plants de même calibre (variété Désirée), mais de sources différentes (I, II et III). Suivant l'origine I, II et III les pourcentages de la contamination par le virus de l'enroulement est respectivement 1,3, 7,8 et 32,6% (fig. 1A). Le rendement moyen obtenu par parcelle est respectivement 12,6, 10 et 7,6 kg (fig. 1C), la différence entre les trois origines étant significative (P<0,05). L'écart de rendement entre les plants de source I et II s'explique sans doute par le taux de levée différent (fig. 1B); mais entre les plants de source II et III, la différence semble provenir de la contamination par le virus et ceci est également observé pour le rendement par pied (fig. 1D). Cette hypothèse est confirmée par l'expérience B ou le rendement obtenu à partir de plants contaminés est comparé à celui du témoin planté avec des tubercules indemnes de virus. L'incidence de la contamination n'est pas correlée au manque à la levée et au rendement des tubercules difformes. Les plants contaminés ont donné pour les variétés Blanka, Up-to-Date et Désirée respectivement 68,7%, 79,2% et 58% du rendement obtenu à partir de tubercules sains, la diminution de rendement étant significative (fig. 3). Les résultats montrent qu'il peut y avoir des

     

Clinical comparison of two regimens of lidocaine infusion in horses undergoing laparotomy for colic

ObjectiveTo compare, in horses undergoing laparotomy for colic, the effects of administering or not administering a loading intravenous (IV) bolus of lidocaine prior to its constant rate infusion (CRI). Effects investigated during isoflurane anaesthesia were end-tidal isoflurane concentration (Fe’ISO), cardiovascular function, anaesthetic stability and the quality of recovery.Study designProspective, randomized clinical study.AnimalsThirty-six client-owned horses.MethodsHorses were assigned randomly to receive lidocaine as a CRI (50 μg kg⁻¹ minute⁻¹) either preceded (LB) or not preceded (L) by a loading dose (1.5 mg kg⁻¹ IV over 15 minutes). Lidocaine infusion (LInf) was started (T0) within 20 minutes after induction of general anaesthesia and discontinued approximately 30 minutes before the end of surgery. Anaesthetic depth, Fe’ISO, intra-operative physiological parameters and quality of recovery were assessed or measured. Data were analysed using one-way anova, t-test, Fisher test, Wilcoxon and Kruskal–Wallis tests as appropriate (p < 0.05).ResultsMean ± SD Fe’ISO was 1.21 ± 0.08% in group LB and 1.23 ± 0.06% in group L. Heart rate was significantly higher in group L than in group LB at times T5-T15, T25, T35 and T95. No difference was found between groups in other measured physiological values, nor in any measure taken to improve these parameters. Recovery phase was comparable and satisfactory in all but one full term pregnant horse in group L which fractured a femur during recovery.ConclusionPreloading with a lidocaine bolus prior to a CRI of lidocaine did not influence isoflurane requirements, cardiopulmonary effects (other than a reduction in heart rate at some time points) or recovery compared to no preloading bolus.Clinical relevanceA loading dose of lidocaine prior to CRI does not confer any advantage in horses undergoing laparotomy for colic.     

Studies on the Nutrition of Spotted Sand Bass Paralabrax maculatofasciatus: Effect of the Dietary Protein Level on Growth and Protein Utilization in Juveniles Fed Semipurified Diets

Two feeding trials were conducted to determine the digestibility of a casein-based semi-purified diet and the effects of different protein levels on growth and protein use of spotted sand bass Paralabrax maculatofasciatus juveniles. For trial I, a semipurified diet with vitamin-free casein as the sole source of protein was fed three times a day to apparent satiation, for a period of 20 d. Feces were collected by siphoning each tank. The digestibility of the experimental diet was high: 97% for protein, 89% for lipids, and 84% for gross energy, whereas that of organic matter was 78%. For trial II, seven diets were formulated using vitamin-free casein at graded levels (25, 30, 35, 40, 45, 50, and 55% protein). Triplicate tanks for each dietary treatment were stocked with fish and fed by hand three times a day to apparent satiation for 6 wk. Perfomance of fish fed the different diets was evaluated for survival, percent weight gain, specific growth rate, feed conversion ratio, and protein efficiency ratio. Survival was 100% for all treatments. Growth of spotted sand bass juveniles increased as the dietary protein increased, but no evidence of reaching a plateau was found. The daily feed intake values showed an inverse relation to the protein content of the diets. The feed conversion ratio did not differ among diets containing 40% protein or greater. The results indicate that spotted sand bass juveniles with 2.5-g mean weight need at least 55% dietary protein for best growth when casein is the sole protein source. However, in terms of feed conversion ratio, the requirement apparently could be lower.     

Dorsal midbrain syndrome associated with persistent neck extension: Clinical and diagnostic imaging findings in 2 dogs

Two young dogs were evaluated for an acute onset of abnormal head posture and eye movement. Neurological examination was characterized mostly by permanent neck extension, abnormalities of pupils, and eye movement. A mesencephalic mass lesion was detected on magnetic resonance imaging in both cases. Neurophysiological pathways likely responsible for this peculiar clinical presentation are discussed.