Blood lead levels of wild Steller's eiders (Polysticta stelleri) and black scoters (Melanitta nigra) in Alaska using a portable blood lead analyzer.

Sea duck populations are declining in Alaska. The reasons for the decline are not known; environmental lead exposure is one suspected cause. Thirty wild Steller's eider ducks (Polysticta stelleri) and 40 wild black scoter ducks (Melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (LeadCare; ESA, Inc., Chelmsford, Massachusetts 01824, USA). Sixty-seven and one-tenth percent of the sea ducks had undetectable blood lead levels, 30.0% had values indicating normal or background lead exposure, and 2.9% had values indicating lead exposure. None of the birds had values indicating lead toxicity, and no birds demonstrated clinical signs of toxicity. Birds in areas with higher human population density had higher blood lead levels than those in less densely populated areas. This is the first time a portable blood lead analyzer has been utilized with sea ducks in a field setting. Because it provides immediate results, it is valuable as a screening tool for investigators carrying out surgical procedures on birds in the field as well as establishing baseline blood lead data on sea ducks. Lead exposure does occur in wild sea ducks, and the study indicates that additional research is needed in order to determine the role environmental lead plays in declining sea duck populations.     

Resting heart rate and tympanic temperature in operant conditioned western lowland gorillas (Gorilla gorilla gorilla).

The conscious, resting heart rate and body temperature of healthy western lowland gorillas (Gorilla gorilla gorilla) is not reported in the literature. To obtain this information, two clinically healthy adult male western lowland gorillas in a training program were conditioned to allow auscultation and obtain tympanic temperatures. The mean heart rate was 73.8 +/- 8.96 beats per minute (n = 176), and it was lower than mean heart rate reported in studies on anesthetized gorillas. The mean tympanic temperature was 35.5 +/- 0.7 degrees C (95.9 +/- 1.23 degrees F) (n = 209). The right tympanic temperature (rtt) and left tympanic temperature (ltt) were recorded separately for one gorilla. A small but statistically significant difference was present between the mean rtt of 35.8 +/- 0.7 degrees C (96.5 +/- 1.2 degrees F) (n = 137) and the mean ltt of 35.7 +/- 0.8 degrees C (96.2 +/- 1.3 degrees F) (n = 121).     

Density estimates of rural dog populations and an assessment of marking methods during a rabies vaccination campaign in the Philippines

We estimated the population density of dogs by distance sampling and assessed the potential utility of two marking methods for capture-mark-recapture applications following a mass canine rabies-vaccination campaign in Sorsogon Province, the Republic of the Philippines. Thirty villages selected to assess vaccine coverage and for dog surveys were visited 1 to 11 days after the vaccinating team. Measurements of the distance of dogs or groups of dogs from transect lines were obtained in 1088 instances (N = 1278 dogs; mean group SIZE = 1.2). Various functions modelling the probability of detection were fitted to a truncated distribution of distances of dogs from transect lines. A hazard rate model provided the best fit and an overall estimate of dog-population density of 468/km² (95% confidence interval, 359 to 611). At vaccination, most dogs were marked with either a paint stick or a black plastic collar. Overall, 34.8% of 2167 and 28.5% of 2115 dogs could be accurately identified as wearing a collar or showing a paint mark; 49.1% of the dogs had either mark. Increasing time interval between vaccination-team visit and dog survey and increasing distance from transect line were inversely associated with the probability of observing a paint mark. Probability of observing a collar was positively associated with increasing estimated density of the dog population in a given village and with animals not associated with a house. The data indicate that distance sampling is a relatively simple and adaptable method for estimating dog-population density and is not prone to problems associated with meeting some model assumptions inherent to mark-recapture estimators.     

Phase II Clinical Trial of Carboplatin in Canine Transitional Cell Carcinoma of the Urinary Bladder

Fourteen dogs with histologically-confirmed transitional cell carcinoma (TCC) of the urinary bladder were treated with 300 mg/m² carboplatin every 3 weeks. Response to therapy was assessed with abdominal radiography, double contrast cystography, urinary bladder ultrasonography and thoracic radiography before therapy and at 6–week intervals during therapy. Dogs were monitored for hematologic toxicity with a CBC and platelet count performed immediately before and 10 to 14 days after carboplatin treatment. Tumor responses included progressive disease in 11 dogs and stable disease in 1 dog. Two dogs were euthanized due to carboplatin toxicity before assessment of tumor response. Toxicity included thrombocytopenia with or without neutropenia in 7 dogs and gastrointestinal toxicity in 6 dogs. Carboplatin therapy was not beneficial in the treatment of TCC in the 14 dogs in this study.     

Water sensitivity, antimicrobial, and physicochemical analyses of edible films based on HPMC and/or chitosan

Several properties of chitosan films associated or not with hydroxypropylmethylcellulose polymer (HPMC) and HPMC films incorporating or not nisin and/or milk fat were studied. Nisin addition at a level of 250 microg mL-1 and likewise chitosan at 1% (w/v) concentration were efficient for total inhibiting Aspergillus niger and Kocuria rhizophila food deterioration microorganisms. HPMC and chitosan films were transparent, whereas nisin and/or fat incorporation induced a 2-fold lightness parameter increase and, consequently, involved more white films. Measurements of tensile strength, as well as ultimate elongation, showed that chitosan and HPMC initial films were elastic and flexible. High thermal treatments and additive incorporation induced less elastic and more plastic films. Water vapor transmission as far as total water desorption rates suggested that chitosan films were slightly sensitive to water. Water transfer was decreased by <60% as compared with other biopolymer films. Regarding its hydrophobic property, the capacity of fat to improve film water barrier was very limited.     

Leaf physiology and morphology of Castanea dentata (Marsh.) Borkh., Castanea mollissima Blume,and three backcross breeding generations planted in the southern Appalachians,USA

Backcross breeding programs have been used to transfer disease resistance and other traits from one forest tree species to another in order to meet restoration objectives. Evaluating the field performance of such material is critical for determining the success of breeding programs. In eastern North America, The American Chestnut Foundation has a backcross breeding program that uses Chinese chestnut (Castanea mollissima Blume) to introduce resistance of the fungal pathogen chestnut blight [Cryphonectria parasitica (Murr.) Barr.] to the native American chestnut [Castanea dentata (Marsh.) Borkh.]. We compared physiological and morphological characteristics among seedlings of American chestnut, Chinese chestnut, and BC₁F₃, BC₂F₃, and BC₃F₃ hybrid chestnuts during their fourth growing season after field-planting. American chestnut and the BC₃F₃ breeding generation displayed photosynthetic light-response curves that were similar to each other but different from Chinese chestnut. Rates of photosynthesis were higher for American chestnut and the BC₃F₃ breeding generation when compared to Chinese chestnut for light levels ≥800 μmol m^?2 s^?1 photosynthetic photon flux density and for maximum photosynthetic capacity. Leaf morphology variables were not different between American chestnut and any of the breeding generations, but leaf area (on a per leaf basis) of Chinese chestnut was lower than that of any other chestnut type. Our results suggest that backcross breeding can be used to transfer desirable traits for restoration of native species threatened by non-native pathogens.     

Conservation status of the world's hagfish species and the loss of phylogenetic diversity and ecosystem function

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Hybridization in Australian Freshwater Crayfish—Production of All-Male Progeny

Abstract.— In freshwater crayfish aquaculture high densities can result from uncontrolled reproduction. Hence some farmers manually sex yabbies Cherax albidus and stock only mate crayfish in farm dams or ponds. Although male-only yabby populations produce an estimated 70% increase in gross income, hand sexing is time consuming and prone to error. A hybridization experiment using freshwater crayfish from the yabby species complex, collected from geographically isolated regions throughout Australia, revealed a hybrid between Cherax rotundus females and C. albidus males which consistently produces only male progeny. This has been confirmed in nine crosses of the same two species. The reciprocal cross of C. albidus females × C. rotundus males produces both male and female progeny. The consistent production of only male progeny by hybridization has not been recorded previously for a crustacean.     

The dissipation of tebuconazole and propiconazole in boronia (Boronia megastigma Nees)

The broad spectrum, systemic fungicides tebuconazole and propiconazole are used to control rust in boronia (Boronia megastigma Nees). Gas chromatography combined with either a benchtop quadrupole mass spectrometer or a high-resolution mass spectrometer allowed for the monitoring of both pesticides in boronia leaves, flowers, and concrete. Field trials were established at two sites to determine the rate of dissipation of tebuconazole and propiconazole in boronia. At site 1, two application rates of 125 and 250 g active ingredient/hectare (ai/ha) tebuconazole were employed. Treatments were repeated 17 days later. At harvest, 286 days after the final application, tebuconazole was detected at levels of 0.06 +/- 0.05 and 0.5 +/- 0.1 [mg/kg +/- standard error, on a dry matter basis (DMB)] in the leaves collected from plots treated with 125 and 250 g ai/ha of tebuconazole, respectively. The oil produced from the flowers collected at the final harvest had residues of tebuconazole at levels of 0.06 +/- 0.03 and 0.10 +/- 0.08 mg/kg for the 125 and 250 g ai/ha application rates, respectively. Two repeat applications of 125 g ai/ha propiconazole were also used at site 1. Residues of propiconazole were detected at 0.09 +/- 0.03 mg/kg (DMB) 286 days after the final application. At site 2, treatments of 125 g ai/ha of tebuconazole were applied twice. At harvest, 279 days after the final application of tebuconazole, residues were recorded at 0.30 +/- 0.09 mg/kg in the leaves (DMB) while the oil produced had 0.20 +/- 0.07 mg/kg.