Linkages between seagrass,mangrove and saltmarsh as fish habitat in the Botany Bay estuary,New South Wales

Shallow-water vegetated estuarine habitats, notably seagrass, mangrove and saltmarsh, are known to be important habitats for many species of small or juvenile fish in temperate Australia. However, the movement of fish between these habitats is poorly understood, and yet critical to the management of the estuarine fisheries resource. We installed a series of buoyant pop nets in adjacent stands of seagrass, mangrove and saltmarsh in order to determine how relative abundance of fishes varied through lunar cycles. Nets were released in all habitats at the peak of the monthly spring tide for 12 months, and in the seagrass habitat at the peak of the neap tide also. The assemblage of fish in each habitat differed during the spring tides. The seagrass assemblage differed between spring and neap tide, with the neap tide assemblage showing greater abundances of fish, particularly those species which visited the adjacent habitats when inundated during spring tides. The result supports the hypothesis that fish move from the seagrass to the adjacent mangrove and saltmarsh during spring tides, taking advantage of high abundances of zooplankton, and use seagrass as a refuge during lower tides. The restoration and preservation of mangrove and saltmarsh utility as fish habitat may in some situations be linked to the proximity of available seagrass.     

Directly observed 15N NMR spectra of uniformly enriched proteins

The proteins cytochrome c2, cytochrome c', and ribulosebisphosphate carboxylase/oxygenase from Rhodospirillum rubrum were enriched in 15N by growth of the organism on 15NH4Cl. The proteins were purified to homogeneity and studied by 15N NMR. Longitudinal and transverse relaxation times as well as the nuclear Overhauser effects were determined for various groups of the proteins which vary in molecular weight from 13,000 to 114,000. The values of these parameters for the amide resonances or for groups thought to be rigid were consistent with the molecular weights of the proteins. Relaxation times of the amino-terminal alpha-amino groups and the side chain nitrogen atoms of arginine and lysine were consistent with much more rapid motion. Nitrogen atoms having bound protons were generally found to be decoupled from the protons by chemical exchange. Demonstrable 1H-15N coupling was taken as an indication that exchange was hindered, either by hydrogen bonding interactions or by inaccessibility of the group to solvent. Histidine side chain nitrogen atoms, which experience a large chemical shift upon protonation/deprotonation, were often found to be broadened beyond detectability by chemical exchange and tautomerization. Strategies for improving sensitivity and for obtaining specific peak assignments are also discussed.     

Viral and Bacterial Pathogens in Bovine Respiratory Disease in Finland

Pathogens causing bovine respiratory tract disease in Finland were investigated. Eighteen cattle herds with bovine respiratory disease were included. Five diseased calves from each farm were chosen for closer examination and tracheobronchial lavage. Blood samples were taken from the calves at the time of the investigation and from 86 calves 3–4 weeks later. In addition, 6–10 blood samples from animals of different ages were collected from each herd, resulting in 169 samples. Serum samples were tested for antibodies to bovine parainfluenza virus-3 (PIV-3), bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCV), bovine adenovirus-3 (BAV-3) and bovine adenovirus-7 (BAV-7). About one third of the samples were also tested for antibodies to bovine virus diarrhoea virus (BVDV) with negative results. Bacteria were cultured from lavage fluid and in vitro susceptibility to selected antimicrobials was tested. According to serological findings, PIV-3, BAV-7, BAV-3, BCV and BRSV are common pathogens in Finnish cattle with respiratory problems. A titre rise especially for BAV-7 and BAV-3, the dual growth of Mycoplasma dispar and Pasteurella multocida, were typical findings in diseased calves. Pasteurella sp. strains showed no resistance to tested antimicrobials. Mycoplasma bovis and Mannheimia haemolytica were not found.     

Habitat characteristics contributing to local occupancy and habitat use in rock pool <Emphasis Type="Italic">Daphnia</Emphasis> metapopulations

The effects of invasive macrophytes, water level fluctuations and predation on freshwater unionids Pyganodon grandis and Utterbackia imbecillis were studied in three small impoundments in Northeastern Texas in 2003–2005. Mussel density was sampled with quadrats. Mortality, associated with the water level fluctuations and predation, was estimated by collecting dead shells on the shore at about two month intervals. In two ponds, horizontal distribution of unionids was limited by dense beds of invasive and noxious macrophytes (mainly Eurasian watermilfoil Myriophyllum spicatum and American lotus Nelumbo lutea): mussel densities were significantly lower in these macrophyte beds (P < 0.001). In the third pond with the lowest density of macrophytes (stonewort Chara sp.), unionids were distributed more evenly, and the average unionid biomass was the highest among all ponds studied. Vertical distribution of unionids in all ponds was likely limited by low oxygen at depth >2 m. The total amount of shells found on the shore per year varied from 0.1% to 28% of the total population in the pond and was negatively correlated with water level (r = −0.72 to −0.81, P < 0.005). Mammalian predators consumed up to 19% of the total unionid population and predation was facilitated by water level fluctuations. Handling editor: K. Martens     

Ecological description of ground beetle communities (Coleoptera, Carabidae) in northern taiga meadows of Arkhangelsk Region

Species composition and ecological structure of ground beetle population was studied in northern taiga meadows of the Arkhangelsk Region. Meadows in the northern forest zone proved to harbor 91 ground beetle species. Carabid complexes formed in the intrazonal biocenoses of the northern forest zone can be as rich as the family topical groups in the southern forest zone by the number of species and ecological diversity. Ecological properties of the fauna and ground beetle population proved similar in different parts of the forest zone. The proportion of stenobiotic meadow species proved to decrease while that of ecologically plastic ones increased from south to north. The proportion of the genus Harpalus decreased in the ground beetle population while the number of Amara species remained unaltered and their abundance increased. The changes in the species composition caused no transformation of the ecological structure of ground beetle population since they were limited to a single life form or guild.     

Antidiabetic and Anticoagulant Properties of Heparin–Glutamic Acid Complex

Natural heparin complexes proved to activate the anticoagulation system. The obtained experimental data convincingly confirm that glutamic acid alone, and particularly in a complex with heparin, has a considerable preventive potential and efficiently protects experimental animals with induced diabetes mellitus.