Integrative approach of histopathology and histomorphometry of common carp (Cyprinus carpio L.) organs as a marker of general fish health state in pond culture

The semi‐intensive system of common carp monoculture in earthen ponds is currently the most practiced fish rearing system in several countries in Eastern Europe. This system is based on the addition of supplemented feed to ponds to achieve faster growth. In this study, the general state of the fish health was monitored when three different types of feeds were used: grain cereals (CF), commercial pelleted feed and extruded feed. The markers used were: (i) the histopathological index (HP) of the main organs: gills, liver and kidney; and (ii) the histomorphometric parameters of the hepatocytes and enterocytes to assess the state of the digestive system in fish fed different types of supplemented feed. At the end of the experiment, the fish were in good health, since irreversible lesions were not noticed to a greater extent in any of the fish organs. There were also no other severe lesions present. However, the results showed differences in the HP indices of the liver and gills, as well as the total HP index, indicating a better health status of the fish in the CF group. The histomorphometric results showed larger cytoplasmic areas of hepatocytes in fish fed CF, which is attributed to glycogen accumulation and higher numbers of goblet cells in the distal intestines of fish fed compound feeds. This can be attributed to slight inflammation.     

Impacts of parasites on marine survival of Atlantic salmon: a meta‐analysis

Parasites can, in theory, have large impacts on the survival of fish populations. One method to evaluate such impacts on anadromous species is to apply manipulative field experiments in which parallel groups of antiparasitically treated and non‐treated fish are simultaneously released and then subsequently recaptured as returning adults. A systematic review and meta‐analysis on all such Norwegian studies on Salmo salar provided a data set for the time period 1996 to 2011 on 118 release groups comprising 657 624 fish released and 3989 recaptured. The overall risk ratio (RR) was estimated to be 1.18 (95% CI: 1.07–1.30). The effect varied strongly between groups, (Higgins I² = 40.1%). Over 70% of this heterogeneity could be explained by the release location, time period and baseline survival. The most important predictor variable was baseline survival. In groups with low recapture in the control group (low baseline survival), the effect of treatment was high (RR = 1.7), while in groups with high recapture in the control group (high baseline survival), there was no effect of treatment (RR ~ 1.00). The most prevalent parasite in the region affected by the drugs administered was Lepeophtheirus salmonis. Hence, the meta‐analysis supports the hypothesis that L. salmonis contributes to the mortality of S. salar during outward migration. However, the effect of treatment was not consistent, but was evidently strongly modulated by other risk factors. The results suggest that the population‐level effects of parasites cannot be estimated independently of other factors affecting the marine survival of S. salar.     

Oxygen consumption of the earthworm species Dendrobaena mrazeki

Dendrobaena mrazeki is an endemic earthworm species inhabiting dry habitats such as pine and thermophilous oak forests in Central Europe. Metabolically, D. mrazeki showed some features typical for endogeic species and some of epigeic ones. In comparison with the related Dendrobaena octaedra, D. mrazeki was a larger earthworm with fresh body mass of adult and subadult individuals of W = 0.59 ± 0.05 g. Its body mass-specific oxygen consumption (M/W = 48 ± 5 μl O₂ g^?1 h^?1, at 15 °C) was the lowest of all earthworms studied (Aporrectodea caliginosa, Aporrectodea rosea, D. octaedra, Lumbricus castaneus, Lumbricus rubellus and Octolasion lacteum), being strongly dependent on W (b from the equation M/W = aW^b about ?0.8). D. mrazeki had low relative water content (77.4% of fresh body mass) and small relative amount of dry weight of the intestinal content (20.1% of dry body mass), which is similar to the epigeic D. octaedra. The respiration rate of D. mrazeki remained the lowest even after recalculating M/W to respiration rate per dry mass or per dry mass without the intestine content to correct for the differences among species in body water content and gut content.     

Effects of Fertigation on Pigment Pattern and Fruit Quality of cv. ‘Gala’ Apples

Fruit pigmentation in ripening cv. ‘Gala, Schniga’ apples was monitored under the influence of fertigation weekly during 21 July–31 August 2009, i.e. 34 days before and 7 days after the optimal harvest date in Slovenia. The soil was a heavy loam clay with high humus content (2.8 %) and high acidity (low pH 4.9). The spectral indices NDVI (Normalized Difference Vegetation Index) and NAI (Normalized Anthocyanin Index) were obtained by a PA 1101 on attached fruit on the transition between the ground and blush colour of the fruit surface. NAI increased slowly from 0.25 to 0.6 two weeks prior to optimum maturity. NDVI values fell from 0.9 to 0.2 before and during ripening, with significant changes starting ca. 3 weeks before and during the week after the optimum harvest date. Fertigation delayed fruit ripening viz harvest date by ca. 4 days. Fertigation delayed changes in the intensity of the fruit’s epidermal pigments, expressed as NDVI for 1 week and NAI for 4 weeks, respectively, but had no significant effect on fruit colour or NDVI and NAI values at the optimal harvest date. At this time, those fruits from the fertigated trees were firmer with a lower starch index compared with the un-fertigated control. Statistically, highly significant correlations were found (p?≤?0.01) (r?=?0.35 to r?=?0.91, R²?=?0.11–0.83) between all the studied spectral and standard parameters i.e. fruit fresh firmness, soluble solids content and starch index.     

1-Naphthaleneacetic acid and 6-benzyladenine thinning of a common slender spindle ‘Jonagold’/M.9 apple orchard. II: Partial tree spraying

Summary

Mature slender spindle ‘Jonagold’/M.9 apple (Malus × domestica Borkh.) trees were thinned using 10 mg l^–1 1-naphthaleneacetic acid (NAA) or 100 mg l^?1 6-benzyladenine (BA) and an axial fan sprayer at a spray volume of 1,500 l ha^?1 applied to the whole canopy, or with smaller volumes, where only the upper half of each canopy was sprayed. Partial spray applications of NAA or BA (at 1,000 l ha^?1, 750 l ha^?1, or 500 l ha^?1) to the upper half of the trees did not cause any reduction in final fruit numbers on the upper half, or on the lower half of each tree. When the whole tree was sprayed to run-off with the same thinning agent, or at 1,500 l ha^?1, successful thinning on both the upper and lower parts of the canopy occurred. Good spray coverage (from 51% to 77%) was also observed on leaves at all canopy positions measured, when whole trees were sprayed at 1,500 l ha^?1.The development of an innovative crop load regulation strategy was an objective of the ISAFRUIT Smartfruit Project.     

Regional Contamination of Moravia (South-Eastern Czech Republic): Temporal Shift of Pb and Zn Loading in Fluvial Sediments

Regional contamination by Pb and Zn in southern Moravia (south-east part of the Czech Republic) in the twentieth century was analysed in Brno Dam lake sediments and in floodplain sediments of the Morava River near Strážnice. The age model for the Brno Dam lake sediments has been obtained by ¹³⁷Cs (maxima corresponding to the nuclear tests in atmosphere and the 1986 Chernobyl accident) and the construction of the dam (1940); the time constraints for the Morava River sediments was the erection of flood defences (1930s) and ²¹⁰Pb dating. In the case of floodplain sediments, profiles exhibiting post-depositional mobilisation of heavy metals by pedogenic processes (gleying) must be excluded to reconstruct the history of contamination. There was a relatively fast joint onset of Pb and Zn load since the early stages of industrialisation in the first half of the twentieth century, but then the concentrations of these two metals developed in a different manner. Pb load only slightly increased till its peak in 1960s and 1970s. The increase of Zn load was rather stepwise: Soon before 1930s (Morava River floodplain) and in 1940s and 1950s (in Brno Lake), the relative contamination by Zn was much lower than during its peak in the 1970s to the present days. The offset of Pb and Zn contamination curves could have been caused by three different artificial sources of these heavy metals. The temporal shift of Pb and Zn loads can be used for dating sediments.     

Thin layer-chromatographic separation of fat soluble and water soluble food dyes

Summary The use of fat soluble and water soluble food dyes in food technology requires reliable proofs and precise identification of these substances in foodstuffs. This problematic has been studied more detailed in our Institute. During these studies some suitable procedures for thin layer chromatographic separation of these substances have been developed.For the separation of fat soluble food dyes the chromatography on thin layers of aluminium oxide and the chromatography on thin layers of starch with reversed phases were used. In the first case good separation was achieved with a solvent system containing petroleum ether and carbon tetrachlorid and their mixtures. In the second case the starch plates were impregnated with paraffin or vegetable oil, and as mobile phases a solvent system containing methanol-water-acetic adic (16 : 3 : 1) and others solvent mixtures currently used in paper chromatography were used.Water soluble food dyes were separated on thin layers of polyamide powder, which was used also for their quantitative isolation from foodstuffs. The best results were achieved with basic solvent system, for example, with a mixture containing ammonia-methanol water (5 : 15 : 80).The developed analytical procedures are suitable for the proof and the separation of fat soluble and water soluble food dyes in all foodstuffs.

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Zusammenfassung Die Verwendung von wasser- und fettlöslichen Lebensmittelfarben erfordert verläßlichen Nachweis und genaue Identifikation dieser Stoffe in den Lebensmitteln. Wir haben diese Problematik in unserem Institut eingehend studiert und einige Verfahren der chromatographischen Trennung dieser Stoffe mittels DC erarbeitet.Zur Trennung der fettlöslichen Farbstoffe verwendeten wir einerseits DC-Platten mit Aluminiumoxid, andererseits führten wir die Trennung dieser Stoffe auf einer dünnen Stärkeschicht mit umgekehrter Phase durch. Im ersten Falle wurde eine gute Trennung mit Laufmitteln erreicht, die Petroläther und Tetrachlormethan und deren Gemische enthalten. Im zweiten Falle wurde als stationäre Phase Paraffinöl, als mobile Phase eine Gemisch von Methanol, Wasser und Essigsäure im Verhältnis 16 : 3 : 1 und andere Gemische in gleichen Verhältnissen verwendet, die sich bei der Papier-Verteilungschromatographie bewährt haben.Wasserlösliche Farbstoffe wurden auf einer dünnen Schicht von Polyamidpulver getrennt, das auch zu deren quantitativer Isolation aus den Lebensmitteln verwendet wurde. Die besten Ergebnisse wurden mit alkalischen Laufmitteln erzielt, z.B. mit dem Gemisch von Ammoniak, Methanol und Wasser im Verhältnis 5 : 15 : 80.Die erarbeiteten analytischen Verfahren für Nachweis und Trennung fett- und wasserlöslicher Lebensmittelfarben bewährten sich für alle Lebensmitteltypen.

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Résumé L'utilisation des colorants alimentaires solubles dans l'eau et dans la graisse exige des preuves sûres et l'identification exacte de ces substances dans les aliments. Nous avons étudié ces problèmes en détail à notre institut et élaboré quelques procédés de séparation chromatographique de ces substances par chromatographie sur couche mince.A la séparation des colorants solubles dans la graisse, nous avons utilisé d'une part des couches versées sur l'alumine, d'autre part la séparation de ces substances sur une couche mince de fécule à phase inverse. Au premier cas une bonne séparation fut atteinte aux systèmes comprenant l'éther de pétrole et le tétrachlore carbonique, ou leurs mélanges. A l'autre cas on applique, comme une phase ancrée, de l'huile paraffinique, comme une phase mobile, du mélange de méthanol, d'eau et d'acide acétique en proportion 16 : 3 : 1 et d'autres en mêmes proportions qui avaient fait leurs preuves à la chromatographie de séparation sur le papier.Les colorants solubles dans l'eau furent séparés sur une couche mince de poudre polyamidé qui avait été de même appliqué à leur isolement quantitatif de l'aliment. Les meilleurs résultats furent atteints avec les systèmes alcalins p.e. avec le mélange de méthanol, d'ammoniac et d'eau en proportions 5 : 15 : 80.Les procédés analytiques élaborés pour des preuves et les séparations des colorants solubles dans la graisse et dans l'eau prouvèrent leur attestation avec tous les types de matières alimentaires.

     

Differential effects of treadmill exercise on calretinin immunoreactivity in type 2 diabetic rats in early and chronic diabetic stages

In this study, we investigated the effects of treadmill exercise on calretinin (CR), a marker of early postmitotic neurons, immunoreactivity in the dentate gyrus (DG) of Zucker diabetic fatty (ZDF) rats, before or after diabetes onset, and Zucker lean control (ZLC) rats. For this study, 6-week-old ZLC and prediabetic ZDF rats, and 22-week-old ZLC and ZDF rats were exercised on the treadmill. Sedentary ZLC and ZDF rats of the same age were used as exercise experiment controls. The exercised prediabetic ZDF rats did not show diabetes onset, while the sedentary prediabetic ZDF rats showed significantly increased blood glucose levels. The exercised diabetic ZDF rats exhibited a decrease in their blood glucose levels compared to the sedentary diabetic ZDF rats, but the levels were still above 20 mmol/l. ZLC rats of both ages were in the normoglycemic range. CR immunoreactivity was detected throughout the DG, including the subgranular zone and the polymorphic layer. Diabetic rats exhibited a significant decrease in the number of CR-immunoreactive cells and fibers in the DG. Exercise in the prediabetic ZDF rats significantly increased the number of CR-immunoreactive cells and fibers in the subgranular zone of the DG. In the ZLC and ZDF rats of chronic diabetic phase, exercise increased CR-immunoreactive neurons in the hilar region. These results suggest that diabetes significantly reduces the number of postmitotic CR-immunoreactive neurons and the intensity of immunoreactivity and that exercise increases these CR-related parameters in a diabetic stage-dependent manner.     

Does meatiness of pigs depend on the level of gastro-intestinal parasites infection?

The aim of the present paper was to determine an influence of the presence and a level of intestine parasites infection on the quality of pork carcass expressed by the content of meat in carcass (meatiness) in pigs. The experimental part of the study was conducted on pigs farm produced in a closed cycle. The population in the study included 120 fattening pigs maintained in two keeping systems: group I--60 individuals kept on slatted floor, and group II--60 individuals kept on deep litter. All the experimental animals were treated in the same manner. The analysed fatteners were slaughtered in Meat Processing Plant when their body mass reached 110 kg, and the post-slaughter assessment was conducted according to the EUROP classification of pigs carcass using the Ultra-Fom 300 device. The study concerning the internal parasites were conducted basing on coproscopic quantitative McMaster method. As a results, the eggs of three nematode taxa were isolated and identified: Oesophagostomum spp., Ascaris suum and Strongyloides ransomi. Overall prevalence of infection of fatteners kept on litter was lower (25%±11.2) as compared to those kept on slatted floor (38.3%±12.6), however the differences were not statistically significant (χ(2)=2.465; df=1; P=0.116). The mean value of meatiness for pigs free from parasites was 53.68, while in the case of infected pigs the meatiness was statistically lower and was 52.12 (t=2.35; P=0.02). The analysed pigs were classified into three categories and conducted analysis of an influence of parasites on meatiness demonstrate the relationship that is statistically significant. The analysis of correlation between meatiness and an average number of helminth eggs also demonstrated the negative, statistically significant, relationship (F=5.52; P=0.020), i.e. in fatteners with higher EPG value the meatiness was lower.