Mycotoxin production by some wood-associated Penicillium spp.

Twenty-five strains of Penicillium spp. isolated from mould-infected discoloured outdoor softwood were analysed for mycotoxin production. Patulin was found to be produced by Penicillium expansion at 4° and 20°C incubation when cultured on wood blocks and wood chips. One strain of P. nordicum (not wood-associated) produced ochratoxin A when cultured on wood chips.     

Impact of habitat fragmentation on the genetics of populations in dendritic landscapes

1. The effect of habitat fragmentation on freshwater species has been addressed using brown trout Salmo trutta L. as a model species with a dendritic population structure. 2. Microsatellite loci were employed as molecular markers. Levels of gene flow and population subdivision were determined in more than 1200 brown trout individuals inhabiting four south European rivers with contrasting patterns of fragmentation, defined by the presence of barriers. 3. The genetic units in the four rivers were restricted by artificial barriers, and gene flow among samples within each river was associated with the level of fragmentation of the river. 4. Loss of genetic diversity and dislocation of the dendritic model have been detected in fragmented rivers. These results emphasise the importance of mitigating the impact of dams by constructing passages to restore gene flow along the river, for fish and other migratory species, as well as the need for caution in relation to stocking in isolated areas to avoid problems of inbreeding.     

The fast phase of optokinetic nystagmus in the locust

ABSTRACT. When their visual environment is rotated about them, freely moving locusts make the typical slow (following) and fast (flick back) phases of optokinetic nystagmus. The fast phase was examined and is compared with that of Crustacea and vertebrates. It is unusual in the locust in that it is symmetrical about the body midline. Mechanoreceptors play a significant role in maintaining the fast phase reset function.     

Surface-bound Immunoglobulin as a Marker of B Lymphocytes in Man

IMMUNOLOGICAL reactions in many species depend on two functionally different types of small lymphocytes, thymus-derived T lymphocytes and bone marrow-derived B lymphocytes¹. In the mouse, the θ antigen is a marker for T lymphocytes, while membrane-bound Ig is found on θ-negative lymphocytes². This has raised the question whether the presence of surface-bound Ig³ may be regarded as a marker for B lymphocytes. We have obtained data indicating that this is the case with human lymphocytes.     

Florida Panther Habitat Selection Analysis of Concurrent GPS and VHF Telemetry Data

Abstract: Florida panthers (Puma concolor coryi) are listed as an endangered subspecies in the United States and they exist in a single Florida population with <100 individuals; all known reproduction occurs south of Lake Okeechobee. Habitat loss is the biggest threat to this small population and previous studies of habitat selection have relied on very high frequency (VHF) telemetry data collected almost exclusively during diurnal periods. We investigated habitat selection of 12 panthers in the northern portion of the breeding range using 1) Global Positioning System (GPS) telemetry data collected during nocturnal and diurnal periods and 2) VHF telemetry data collected only during diurnal periods. Analysis of both types of telemetry data yielded similar results as panthers selected upland (P < 0.001) and wetland (P < 0.001) forested habitat types. Our results indicated that forests are the habitats selected by panthers and generally support the current United States Fish and Wildlife Service panther habitat ranking system. We suggest that future studies with greater numbers of panthers should investigate panther habitat selection using GPS telemetry data collected throughout the range of the Florida panther and with location attempts scheduled more evenly across the diel period. Global Positioning System radiocollars were effective at obtaining previously unavailable nocturnal telemetry data on panthers; however, we recommend that panther researchers continue to collect VHF telemetry data until acquisition rates and durability of GPS collars improve. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):633–639; 2008)