Barnacle culture: background,potential and challenges

There are approximately a dozen species of commercially interesting barnacles worldwide, some of which have been cultured on a semi‐industrial scale. These species are listed and information is provided with regard to geographical distribution, landings and prices. Traditionally, ‘goose’ barnacles (four species) are considered to be the most important for consumption. World production already stands at 500 tonnes year^?1, but this species has not been cultured to date. Some ‘acorn’ barnacles are also consumed (seven species), with harvest levels per species that do not exceed 200 tonnes year^?1 and selling prices that can reach US$17/kg. ‘Acorn’ barnacle culture on a world scale is still developing. Nevertheless, production has occurred on a semi‐industrial scale; specifically, spat have been collected from the wild and grown in suspended systems. Farming trials have focused on two species of acorn barnacles: Austromegabalanus psittacus (Molina 1782) ‘picoroco’ in Chile and Megabalanus azoricus (Pilsbry 1916) ‘craca’ in Portugal. The large‐scale production of these crustaceans will depend on the optimization of spat collection from the wild and/or the parallel development of mass production technologies for larvae (hatcheries). In addition, further development will be achieved by opening up new markets for commercialization.     

Influence of lignification and feruloylation of maize cell walls on the adsorption of heterocyclic aromatic amines

Both epidemiological and experimental data indicate that a diet rich in fiber may reduce cancer risk. One possible mechanism is by adsorbing carcinogens and transporting them out of the body without metabolic activation. We investigated the role of fiber lignification and feruloylation on the adsorption of four of the most relevant heterocyclic aromatic amines in food: 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), and 2-amino-9H-pyrido[2,3-b]indole (AalphaC). Adsorption experiments, under conditions mimicking the small intestine, were carried out using nonlignified and artificially lignified primary maize walls with defined lignin and ferulate/diferulate concentrations and defined lignin compositions. Lignin concentration and composition both influenced the adsorption of heterocyclic aromatic amines, especially the more hydrophobic types. Heterocyclic aromatic amine adsorption increased with lignin concentration. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine and 2-amino-9H-pyrido[2,3-b]indole were better adsorbed by guaiacyl-rich lignins, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline by syringyl-rich lignins, whereas the adsorption of 2-amino-3-methylimidazo[4,5-f]quinoline was not clearly influenced by lignin composition. Nonlignified cell walls adsorbed lesser amounts of heterocyclic aromatic amines. Variations in cell wall feruloylation had no effect on heterocyclic aromatic amine adsorption.     

Overstory-specific effects of litter fall on the microbial carbon turnover in a mature deciduous forest

Mature deciduous forests can serve as important carbon (C) sinks, but the C storage differs significantly in dependency on the tree species. To specify the significance of overstory-specific effects of litter fall on the soil microbial C turnover, we have investigated the ¹³C isotopic signature of microbial biomarker phospholipid fatty acids (PLFAs). Samples were taken under pure Fagus sylvatica and mixed overstory (F. sylvatica and Fraxinus excelsior or F. excelsior, Acer spp. and F. sylvatica) in a mature temperate deciduous forest in Central Germany 4 weeks prior to and 3 weeks after litter fall. Accordingly, the CO₂ emission from soil was measured before, during and after the litter fall to investigate the response of decomposition. At all sites and at both sampling dates the fungal biomarker PLFA 18:2ω6,9 had predominantly lower δ¹³C values (from −32 to −43‰) than the bacterial biomarker PLFAs (δ¹³C values from −23 to −39‰). This difference indicated that fungi generally used preferentially plant derived C, whereas the bacterial populations include groups which used SOM derived C, independent on the overstory trees. Under pure F. sylvatica overstory the δ¹³C values of microbial biomarker PLFAs were slightly decreased (up to 2‰ for 17:0br) or unchanged after litter fall. By contrast, under both variants of mixed overstory the δ¹³C values of biomarker PLFAs of fungi (18:2ω6,9) were increased after litter fall (+3.5 and +3.8‰). This might be explained partly by a faster initial decomposition of foliar litter from mixed overstory already during litter fall as confirmed by higher CO₂ emission under mixed F. excelsior, Acer spp. and F. sylvatica than under pure F. sylvatica in this period. However, the involved microbial populations differed overstory-specific. Bacterial biomarker PLFAs with strongest overstory-specific differences in the response on litter fall were 17:0br (Gram-positive bacteria), 18:1 and 19:0cy (Gram-negative bacteria). The present results indicate that a tree species conversion even exclusively between deciduous tree species might alter the soil microbial C turnover during litter decomposition and suggest that it would in the long-term change the SOM stability and C storage.     

Hormonal changes and follicular activity after treatment with intravaginal progesterone‐releasing devices in llamas

Plasma progesterone (P₄) concentrations and follicular activity after administration of different P₄ doses were evaluated in 33 adult female llamas treated with intravaginal devices. In Study 1, a group of llamas (n = 10) was treated with an intravaginal device (IVD) containing 160 (n = 5) or 780 mg of P₄ (n = 5). Based on the results from the first study, in Study 2, females with follicles at different stages of development were treated with the IVD containing 780 mg of P₄ (n = 21) or remain untreated (control; n = 12) to evaluate the effect of P₄ on follicular activity. In Study 1, the IVD containing 160 mg of P₄ induced follicular turnover in 60% of females while the remaining 40% of llamas developed persistent follicles. Thus, this device controlled follicular activity in llamas, although it promotes the persistence of follicles present at start of treatment. Conversely, in both studies, the IVD containing 780 mg of P₄ suppressed follicular development and hasten the emergence of a new follicular wave in all females regardless of the follicular phase at insertion. Additionally, in Study 2, this device effectively concentrated the appearance of follicles with ovulatory diameter at a definite time after treatment in comparison with control animals. In conclusion, treatment with an IVD containing 780 mg of P₄ would be considered for the control of follicular activity in llamas as it ensures the presence of a young follicle with ovulatory diameter by day 6 after the end of treatment in all females.     

Evaluation of Efficacy and Safety of Zinc Gluconate Associated with Dimethyl Sulphoxide for Sexually Mature Canine Males Chemical Neutering

The aim of this research was to evaluate the efficacy of zinc gluconate associated with dimethyl sulphoxide (DMSO) for chemical neutering in canine males. Fifteen sexually mature male dogs were divided in two groups, named control and treated. An injection was administered to both testicles, at a concentration of 26.2 mg zinc gluconate per ml and 0.5% DMSO in the treated group (11 dogs). The control group was given injections of saline solution (four dogs). Clinical examination and blood collection for a haemogram were done both before and after drug injection. There were 12 spermograms performed to analyse sperm motility, sperm vigour, ejaculate volume, testicle size, pathology and sperm concentrations. Libido was also measured. An ultrasound examination and histopathology were performed at the end of the experiment. Dogs’ libido after chemical injection was reduced by over 50%. The spermogram analysis showed final mean results of 14.54% for sperm motility, 0.72 of sperm vigour and 37 150 per million spermatozoa per millilitre, values considered below the necessary levels at which fertilization can occur. Ultrasound and histopathology analyses of testicles for the treated group revealed more intense injuries when compared with the control group, with compromised testicular parenchyma and a decrease of germ cell number leading to total atrophy, indicating that the treatment reduced the fertilizing potential of male dogs, promoting a possible subfertile status.     

Zygomatic gland adenoma in a dog: histochemical and immunohistochemical evaluation

Orbital epithelial tumors in dogs are rare and most frequently malignant. Distinguishing their origin from the lacrimal or zygomatic gland is often challenging and is based mostly on tumor location. A case of adenoma involving the orbit in a 13-year-old, female, standard Schnauzer is reported. Histologically, the neoplasm was characterized by nests and cords of epithelial cells mostly forming small glandular structures. The origin of the tumor from the zygomatic gland was determined by histochemical characteristics (alcian blue pH 1 positive staining) of a small remnant of normal gland included within the tumor capsule. The benign nature of our finding was confirmed by follow-up information: 2 years after complete surgical removal of the mass no tumor recurrence or metastases was recorded.     

Bestimmung der S-Allele in Brennkirschensorten (Prunus avium L.)

Zusammenfassung Brennkirschen sind Süßkirschensorten, welche spezielle Eigenschaften für die Branntweinproduktion und die industrielle Verarbeitung besitzen. Ihr Hauptanbaugebiet in Deutschland befindet sich in Baden-Württemberg und in Teilen Bayerns. In den letzten Jahren wurde über einen geringen Fruchtbehang in neu gepflanzten Brennkirschenanlagen berichtet. Süßkirschen sind selbstinkompatibel und benötigen deshalb eine Bestäubersorte. Ursache ist ein gametophytischer Selbstinkompatibilitätsmechanismus, bedingt durch einen S-Lokus. Mit Hilfe molekularer Marker wurden deshalb Untersuchungen zu den S-Allel-Kombinationen in 62 Brennkirschensorten bzw. -herkünften aus dem Raum Oberkirch, Mittelbaden, durchgeführt. Im Ergebnis konnten zwei bisher noch nicht beschriebene S-Allele und 14 neue Inkompatibilitätsgruppen ermittelt werden. Ursache für den schlechten Fruchtansatz in neuen Kirschenanlagen mit den Hauptsorten Dolleseppler und Benjaminer sind die gleichen S-Allel-Kombinationen (S₁S₇) in beiden Sorten. Als mögliche Befruchtersorten werden die Sorten Schwarze Schüttler (S₆S₇), Hartwälder (S₄S₇), Feuerkirsche (S₄S₁₄) und die ehemalige Sorte Dolleseppler der Baumschule Kiefer (S₁S₄) empfohlen.     

Glycoside Hydrolase Family 51 α‐l‐Arabinofuranosidases from Clostridium thermocellum and Cellvibrio japonicus Release O–5‐Feruloylated Arabinose

Arabinofuranosidases act synergistically with other enzymes to depolymerize arabinoxylans by cleaving arabinofuranose substituents from the β‐(1→4)‐linked d ‐xylopyranose backbone. Because arabinose feruloylation is a barrier to some, but not all, arabinofuranosidases, we investigated the actions of three α‐l ‐arabinofuranosidases from the glycoside hydrolase (GH) family 51 on feruloylated arabinoxylan‐oligosaccharide standard compounds with and without feruloyl esterase. GH51 α‐l ‐arabinofuranosidases from Clostridium thermocellum and Cellvibrio japonicus both partially released feruloylated arabinose (up to 59% for C. thermocellum). Simultaneous incubation with arabinofuranosidases and feruloyl esterase quantitatively released arabinose from feruloylated standard compounds. Therefore, although feruloylation does not completely obstruct GH51 arabinofuranosidases, synergistic approaches utilizing multiple enzymes remain the most effective tactic for enzymatic breakdown of feruloylated compounds.