Untersuchungen zur Bekämpfung der Kohlschotenrüßler-und Kohlschotenmücken-Larven mit Ester-und Gamma-Hexa-Mitteln

Zusammenfassung Die Vernichtung der Larven von Kohlschotenrüßler und Kohlschotenmücke in den Schoten ist durch Behandlung der Rapspflanzen mit Ester- und Gamma-Hexa-Mitteln grundsätzlich möglich.Ester, insbesondere E 605, sind schon mit niedrigeren Konzentrationen wirksam als Gamma-Hexa-Mittel.Stäubemittel sind wegen der zur Larvenabtötung notwendigen sehr hohen Dosierung für die Praxis weniger zu empfehlen.Für die Larvenbekämpfung im Feldbestand ist das E 605 forte-Spritzmittel und zwar in 1,5%iger Konzentration gut geeignet.     

Comparison of growth,digestive system maturation and skeletal development in sea bass larvae reared in an intensive or a mesocosm system

The quality of development in intensive or mesocosm hatchery‐reared Dicentrarchus labrax larvae was investigated using physiological indicators assessing ontogeny. Larvae were reared in intensive (120 L tanks) and in mesocosm systems (20 m³ enclosures) with the same feeding sequence, excluding the wild zooplankton naturally available in mesocosms. Faster growth was recorded since early development [16 day after hatching (DAH)] in the mesocosm. Maturation of the digestive system also occurred earlier as indicated by the higher amylase secretion ratios, the intestinal maturation index (alkaline phosphatase/leucine–alanine peptidase and aminopeptidase‐N/leucine–alanine peptidase ratios) and the more developed intestinal epithelium at 23 DAH. Nevertheless, the delay in digestive maturation in the intensive system seemed retrieved within few days. In both the groups, the number of vertebrae ranged between 24 and 26, with the dominant class being 25 vertebrae. However, the distributions differed between treatments for meristic characteristics, ossification stages and incidence of malformation types. Loss of a vertebra was more frequent in the intensive system, while the appearance of an additional vertebra was more frequent in the mesocosm. Ossification at 37 DAH was also more advanced in the mesocosm in addition to a lesser rate and severity of skeletal malformations. It is suggested that the early nutritional contribution of mesocosm wild zooplankton, yet at densities of 0.2–0.7 prey mL^?1, had key effects on larvae development since the early stages.     

Mitochondrial genome-knockout cells demonstrate a dual mechanism of action for the electron transport complex I inhibitor mycothiazole

Mycothiazole, a polyketide metabolite isolated from the marine sponge Cacospongia mycofijiensis, is a potent inhibitor of metabolic activity and mitochondrial electron transport chain complex I in sensitive cells, but other cells are relatively insensitive to the drug. Sensitive cell lines (IC(50) 0.36-13.8 nM) include HeLa, P815, RAW 264.7, MDCK, HeLa S3, 143B, 4T1, B16, and CD4/CD8 T cells. Insensitive cell lines (IC(50) 12.2-26.5 μM) include HL-60, LN18, and Jurkat. Thus, there is a 34,000-fold difference in sensitivity between HeLa and HL-60 cells. Some sensitive cell lines show a biphasic response, suggesting more than one mechanism of action. Mitochondrial genome-knockout ρ(0) cell lines are insensitive to mycothiazole, supporting a conditional mitochondrial site of action. Mycothiazole is cytostatic rather than cytotoxic in sensitive cells, has a long lag period of about 12 h, and unlike the complex I inhibitor, rotenone, does not cause G(2)/M cell cycle arrest. Mycothiazole decreases, rather than increases the levels of reactive oxygen species after 24 h. It is concluded that the cytostatic inhibitory effects of mycothiazole on mitochondrial electron transport function in sensitive cell lines may depend on a pre-activation step that is absent in insensitive cell lines with intact mitochondria, and that a second lower-affinity cytotoxic target may also be involved in the metabolic and growth inhibition of cells.     

Does the diet of the Balearic population, a Mediterranean-type diet, ensure compliance with nutritional objectives for the Spanish population?

OBJECTIVES: To assess the dietary habits of Balearic Islands' consumers who are successful in meeting current nutritional recommendations, to find clues for the development of future food-based dietary guidelines (FBDG) that would be relevant to this population. DESIGN: Cross-sectional nutritional survey carried out in the Balearic Islands between 1999 and 2000. SUBJECTS AND METHODS: Dietary habits were assessed by means of 24-hour recall (two non-consecutive days: warm and cold season) and a food-frequency questionnaire in a random sample (n=1200, aged 16-65 years) living in private households. Differences in percentage of compliers with the intermediate nutritional objectives for the Spanish population and differences in food consumption patterns between genders and between high (above the upper quartile of intake) and low (below the lower quartile of intake) consumers of fat, saturated fatty acids (SFA), fibre, and fruit and vegetables were analysed. RESULTS: Gender differences were observed in nutrient and energy intakes, as well as in attainment of the recommendations. Less than 25% of the population reached the intermediate nutritional recommendations for iodine, fruit, carbohydrates, SFA, fibre and vegetables. Low fat/SFA and high fruit and vegetables/fibre consumers kept a diet in line with the traditional Balearic diet and prevailing dietary pyramids, which ensured better compliance with the nutritional goals. CONCLUSIONS: The intermediate nutritional objectives for the Spanish population could be achieved through maintenance of the traditional Balearic diet, a Mediterranean-type diet in the Balearic population. Therefore, this dietary model could be used to develop FBDG relevant to this population.     

The effect of light intensity on first feeding of the spotted sand bass Paralabrax maculatofasciatus (Steindachner) larvae

The effects of light intensity on feeding incidence and prey consumption at first feeding of spotted sand bass larvae (Paralabrax maculatofasciatus Steindachner), using four light intensity treatments (0, 100, 400, and 700 lx) were evaluated. Specimens were fed the rotifer Brachionus plicatilis at a density of 3 rotifers mL^?1. One hour after the addition of prey, 30±3 (mean±SEM) larvae were sampled from each treatment aquarium. Feeding incidence was evaluated as the percentage of larvae with prey in the digestive tract. Feeding intensity was measured as the number of prey in the digestive tract of the larvae. Histological analysis was carried out to describe the eye structure at the time of first feeding. Larvae fed in darkness (0 lx) had a significantly lower (P<0.05) feeding incidence (1.2±2.2%) and intensity (0.4±0.7 rotifers larvae^?1) than those larvae fed at 100 (28±11%, 1.8±0.2 rotifers larvae^?1), 400 (48±10%, 2.4±0.3 rotifers larvae^?1), and 700 lx (52±4%, 2.4±0.1 rotifers larvae^?1). Feeding incidence of the spotted sand bass larvae increased with light intensity while the feeding intensity showed no significant difference (P>0.05) between light treatments. Histological analysis of the eye structure showed that first feeding larvae had well‐formed lens along with a retina composed of pure single cones as photoreceptors.     

Mortality of eggs and third instar larvae of Anastrepha ludens and A. obliqua with insecticidal controlled atmospheres at high temperatures

The in vitro mortality of eggs and third instar larvae of Anastrepha ludens and A. obliqua was determined after exposure to 21 treatments of air or controlled atmospheres (CA) at high temperatures and 50% RH. Air at 44°C for 160 min caused very low mortality, which increased significantly by CA. Higher temperatures caused a more rapid kill. One hundred percent mortality was achieved for third instar larvae of both species in air or CA at 48°C for 220 min. A 100% mortality of eggs of A. ludens was achieved in air at 51°C for 240 min or in CA at 52°C for 240 min, and 100% mortality of eggs of A. obliqua was achieved in air or in CA at 55°C for 240 min. A. obliqua was slightly more tolerant than A. ludens, and eggs were more tolerant than third instar larvae in both species. CA had a synergistic effect at <50°C, but was slightly less effective than air at higher temperatures. Low O₂ concentrations were more effective than high CO₂ levels. The mean estimated temperatures for 50, 99 and 99.9968% mortality (LT₅₀s, LT₉₉s, LT_99.9968s) of eggs of A. obliqua (the most tolerant) exposed to 0 kPa O₂+50 kPa CO₂ for 240 min were 49.4, 54.8 and 60.9°C, respectively. We conclude that dry hot air at ≥44°C and 50% RH in CA (0 kPa O₂+50 kPa CO₂), for 160 min or longer, is effective in increasing mortality of eggs and third instar larvae of A. ludens and A. obliqua.     

Cryopreservation of YamúBrycon siebenthalae Milt

The yamú Brycon siebenthalae is an endemic fish of the Orinoco river basin, but wild stocks are decreasing because of the disruption of their habitat. We evaluated a protocol for the cryopreservation of yamú sperm to contribute to the preservation of this endangered genetic resource. Milt was mixed with a cryoprotectant medium (5.5% glucose, 12% egg yolk, and 5%, 10%, or 15% dimethyl sulfoxide - DMSO) in a ratio 1:4 (milt:medium), stored in 0.5-mL French straws, frozen in nitrogen liquid vapor (-76 C), then immersed and stored in liquid nitrogen for 10 d or 12 mo. Motility of thawed spermatozoa was higher ( P < 0.001) in 10% DMSO medium than 5% DMSO or 15% DMSO mediums; but lower than the control ( P < 0.001). With sperm cryopreserved, the highest level of fertilization was achieved with 10% DMSO ( P < 0.001) after 10 d or 12 mo of cryopreservation. Fertilization of eggs inseminated with 6.4 × 10⁹ spermatozoa per g of eggs was higher ( P <0.05) than with 1.6 × 10⁹ spermatozoa per g of eggs. There was no difference (P > 0.05) in fertilization between insemination doses of 3.2 × 10⁹ and 6.4 × 10⁹ spermatozoa per g of eggs. Cryopreservation of yamu milt can be performed successfully with a simple medium combined with 10% of DMSO as cryoprotectant. The highest level of fertility was achieved using between 3 × 10⁹ and 6 × 10⁹ spermatozoa per g of fresh eggs.     

Effects of culture conditions on feeding response of larval Pacific red snapper ( Lutjanus peru, Nichols & Murphy) at first feeding

Feeding incidence or number of larvae with preys (FIC) and intensity or number of prey per larvae (FIT) at first feeding of Pacific red snapper ( Lutjanus peru) larvae was investigated under different conditions: prey type (rotifer and copepod nauplius) and density, nauplii size, light intensity, water temperature, salinity and microalgae concentration. Rotifers were not consumed at any prey density and FIC increased significantly when a high nauplii density (10 > 1, 0.1 mL^?1) and light intensity (2000 > 1000, 500, 0 lx) were supplied. In a multifactorial experiment where light intensity (2000, 2500, 3000 lx), tank colour (grey and black) and prey type (nauplii and a mixed diet: rotifers and nauplii) were tested, a significant difference was found only for light intensity and prey type with a significant interaction between these factors. FIC was significantly higher with nauplii stage I–III than IV–VI and also at 25 °C than at 28 °C. Green water (0, 0.3 × 10⁶ or 1 × 10⁶ cells mL^?1) and salinity (25, 30, 35 gL^?1) did not affect FIC. FIT was not affected by any variables tested except in the density experiment where it was significantly higher at 10 nauplii mL^?1.     

Allometric growth patterns and development in larvae and juveniles of thick‐lipped grey mullet Chelon labrosus reared in mesocosm conditions

Allometric growth and ontogeny were studied in thick‐lipped grey mullet Chelon labrosus reared in mesocosms from 1 to 71 day post hatching (dph). Multivariate allometric analysis of morphometric growth distinguished three distinct developmental stanzas separated by two morphometric metamorphosis lengths (L_m1 = 4.46 ± 0.06 mm; L_m2 = 28.56 ± 1.04 mm). Body mass growth also showed three distinct episodes separated by two inflections, correlated with morpho‐functional changes. First episode concerned pre‐flexion larvae and ended around 4.5 mm‐L_T (14‐dph), coinciding with estimated L_m1. It was distinguished by reduced growth, but intense morphogenesis and differentiation processes. Organogenesis and allometric changes indicated that development priorities concerned feeding efficiency, by improving detection ability (sensory system development), ingestion capacity (head growth) and assimilation performance (digestive system differentiation), together with respiration efficiency (gill development). Second episode concerned post‐flexion larvae and, ended around 8.6 mm‐L_T (25‐dph). It was distinguished by fast growth of trunk and tail, acquisition of adult axial muscle distribution and completion of gill filament development, improving locomotion and oxygenation performances. It corresponded to transition towards metamorphosing stage as indicated by later isometric growth, musculature maturation and acquisition of juvenile phenotype. Metamorphosis seemed to end at L_m2, suggesting to avoid zootechnic handling before this size.