A high-resolution radiation hybrid map of the human genome draft sequence

We have constructed a physical map of the human genome by using a panel of 90 whole-genome radiation hybrids (the TNG panel) in conjunction with 40,322 sequence-tagged sites (STSs) derived from random genomic sequences as well as expressed sequences. Of 36,678 STSs on the TNG radiation hybrid map, only 3604 (9.8%) were absent from the unassembled draft sequence of the human genome. Of 20,030 STSs ordered on the TNG map as well as the assembled human genome draft sequence and the Celera assembled human genome sequence, 36% of the STSs had a discrepant order between the working draft sequence and the Celera sequence. The TNG map order was identical to one of the two sequence orders in 60% of these discrepant cases.     

Behavioural interactions of seabirds with suspended mussel longlines

Increased abundances of a number of seabird species have been found in areas of mussel longline aquaculture (compared to control sites) in a recent study at Bantry Bay, southwest Ireland. The aim of this study was to investigate whether this form of mussel aquaculture also affects the activity budgets and foraging behaviour of these seabirds. Scan-sampling was used to compare seabird activity budgets between three areas of mussel longline aquaculture and three control sites. Foraging activities of Great-Northern Divers Gavia immer, an Annex 1 species under the Euopean Union's Birds Directive, were also compared between sites using focal sampling. The behaviour of gulls (Larus sp.), Cormorants Phalacrocorax carbo, Shags Phalacrocorax aristotelis and Great-Northern Divers (but not auks, Alcidae) differed significantly between areas of mussel aquaculture and control sites in this study. Mussel suspension buoys were heavily utilized by gulls, cormorants and shags as safe perching platforms for preening activities. Gulls also fed extensively on epifauna attached to the buoys. Great-Northern Divers spent more time snorkelling (head submerged in search of food) in mussel sites than in the control sites, however dive duration and visible foraging success rates did not differ significantly between sites. Overall, the environmental impact of mussel suspension culture appears to be positive or neutral on marine bird species occurring at this study site.     

Effects of cryptic mortality and the hidden costs of using length limits in fishery management

Fishery collapses cause substantial economic and ecological harm, but common management actions often fail to prevent overfishing. Minimum length limits are perhaps the most common fishing regulation used in both commercial and recreational fisheries, but their conservation benefits can be influenced by discard mortality of fish caught and released below the legal length. We constructed a computer model to evaluate how discard mortality could influence the conservation utility of minimum length regulations. We evaluated policy performance across two disparate fish life‐history types: short‐lived high‐productivity (SLHP) and long‐lived low‐productivity (LLLP) species. For the life‐history types, fishing mortality rates and minimum length limits that we examined, length limits alone generally failed to achieve sustainability when discard mortality rate exceeded about 0.2 for SLHP species and 0.05 for LLLP species. At these levels of discard mortality, reductions in overall fishing mortality (e.g. lower fishing effort) were required to prevent recruitment overfishing if fishing mortality was high. Similarly, relatively low discard mortality rates (>0.05) rendered maximum yield unobtainable and caused a substantial shift in the shape of the yield response surfaces. An analysis of fishery efficiency showed that length limits caused the simulated fisheries to be much less efficient, potentially exposing the target species and ecosystem to increased negative effects of the fishing process. Our findings suggest that for overexploited fisheries with moderate‐to‐high discard mortality rates, reductions in fishing mortality will be required to meet management goals. Resource managers should carefully consider impacts of cryptic mortality sources (e.g. discard mortality) on fishery sustainability, especially in recreational fisheries where release rates are high and effort is increasing in many areas of the world.     

Designing the ideal habitat for entomopathogen use in nursery production

BACKGROUND: Greenhouse and nursery producers use entomopathogens (nematodes and fungi) to control soil pests. Although it is known that the physical and chemical properties of mineral soil significantly impact upon soil pathogens, the influence of soilless media used for plant production on entomopathogen performance is poorly understood. RESULTS: Survival and foraging distance were differently affected by sand:peat, bark and sawdust media for entomopathogenic nematodes, but not for the immobile fungus Metarhizium anisopliae. Redwood sawdust medium consistently had a negative impact upon entomopathogenic nematodes. Dividing media into individual components supported the hypothesis that redwood sawdust reduced foraging and infection abilities of S. riobrave and H. bacteriophora. Physically altering the components by adding sand significantly improved foraging and infection success for S. riobrave in media not optimum for foraging. CONCLUSION: This study is the first to highlight the importance of selecting the appropriate soilless media and pathogen species combinations to increase efficacy of biological control. H. bacteriophora was able to find hosts in a wider diversity of medium components than S. riobrave, although both nematode species performed well in peat moss and recycled plant material. These results suggest that peat moss, recycled plant material and hardwood bark are components amenable to EPN biological control programs. Copyright © 2012 Society of Chemical Industry     

Site fidelity,survival and conservation options for the threatened flapper skate (Dipturus cf. intermedia)

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Urban Influences on Stream Chemistry and Biology in the Big Brushy Creek Watershed, South Carolina

Naturally high total dissolved solids and upstream agricultural runoff often mask the influence of urban land cover on stream chemistry and biology. We examined the influence of headwater urbanization on the water chemistry, microbiology, and fish communities of the Big Brushy Creek watershed, a 96 km² drainage basin in the piedmont of South Carolina, USA. Concentrations of most major anions and cations (especially nitrate, sulfate, chloride, sodium, potassium, and calcium) were highest in the urban headwaters and decreased downstream. Generally, the highest concentrations of suspended coliform bacteria occurred in the urban headwaters. In contrast, stream habitat quality and the abundance, species richness, and species diversity of fishes did not differ significantly between urban and rural sites. Discharge of wastewater treatment plant effluent at one rural location caused an increase in concentrations of many solutes and possibly the abundance of benthic algae. We hypothesize that atmospheric dry deposition and domestic animal wastes are important sources of stream solutes and of coliform bacteria, respectively, in the urban headwaters. The lack of significant differences in fish abundance and diversity between urban and rural sites may indicate that urban development in the Big Brushy Creek watershed has not yet degraded habitat conditions greatly for stream fishes. Alternatively, agriculture or other land uses may have degraded stream habitat quality throughout the watershed prior to urbanization.     

Canine Idiopathic Thrombocytopenic Purpura

Canine idiopathic thrombocytopenic purpura (ITP) is a disease in which antibodies bound to the surface of platelets mediate premature platelet destruction by macrophages. ITP in dogs and chronic ITP in humans are analogous diseases. This article draws on information from the literature on ITP in dogs and in humans, and reviews the pathogenesis, diagnosis, and treatment of ITP in dogs. J Vet Intern Med 1996;207–218. Copyright © 1996 by the American College of Veterinary Internal Medicine .     

Intervals from norgestomet withdrawal and injection of equine chorionic gonadotropin or P.G. 600 to estrus and ovulation in ewes

Synchronization of estrus and ovulation is essential for AI of ewes during a predetermined time frame, and progestogen-eCG treatments are typically used to prepare the ewes. However, eCG is not readily available in the United States, but P.G. 600 (400 IU of eCG and 200 IU of hCG) is available. Thus, we conducted a study to determine the effects of eCG and P.G. 600 on the timing of estrus and ovulation after progestogen withdrawal. Ewes were assigned to two replicates of an experiment with the following treatments: 1) 3-mg norgestomet implant (i.e., one-half of a Syncro-Mate-B [SMB] implant) for 10 d, plus 2 mL of saline i.m. at SMB removal (n = 11); 2) 3-mg SMB implant for 10 d, plus 400 IU of eCG i.m. at SMB removal (n = 13); and 3) 3-mg SMB implant for 10 d, plus P.G. 600 i.m. at implant removal (n = 9). On d 6 after SMB insertion, PGF2alpha was used to induce luteolysis. Beginning 12 h after implant removal, vasectomized rams were used at 12-h intervals to check for estrus. When a ewe was detected in estrus, each ovary was evaluated ultrasonically. Ovaries were evaluated again 16 h later and then at 8-h intervals until ovulation. Treatment altered the interval from implant removal to estrus (less [P < 0.05] in SMB + eCG than in the other two groups) and to ovulation (greatest [P < 0.05] in SMB). However, the treatment x replicate interaction was significant for the intervals from implant removal to estrus (P < 0.03) and from implant removal to ovulation (P < 0.05). An inconsistent response in the SMB-treated ewes seemed to be primarily responsible for the interaction. The intervals to estrus and to ovulation for the SMB-treated ewes were shorter (P < 0.05) in Replicate 1 than in Replicate 2. Also, both intervals seemed to be less consistent between replicates for the SMB + P.G. 600- than for the SMB + eCG-treated ewes; that is, eCG seemed to increase the predictability of the intervals to estrus and to ovulation. Neither the main effects of treatment and replicate nor their interaction were significant for the interval from estrus to ovulation (38.4 /- 3.3 h), size of the ovulatory follicle (7.7 +/- 0.8 mm), or ovulation rate (1.6 +/- 0.2). We concluded from this experiment that eCG is a better choice than P.G. 600 as the gonadotropin to use at the time of progestogen withdrawal to prepare ewes for AI during a predetermined interval.