Variation in moth occurrence and implications for foraging habitat of Ozark big-eared bats

We investigated patterns of moth occurrence among habitats in two different landscapes surrounding roosts of the endangered Ozark big-eared bat (Corynorhinus townsendii ingens) from May to August 2005, and compared these data with published results on the diet of this subspecies. Landscapes were situated in the Ozark Mountains, USA, and consisted of a fragmented, agricultural landscape and a contiguous national forest. We captured 8720 moths constituting ≥314 species and 22 families. Pastures demonstrated a lower abundance and richness of moths than other habitats in the fragmented landscape (p < 0.05). Neither abundance nor richness of moths varied by habitat in the forested landscape, but we did observe variation among roost locations (p < 0.05). Abundant families of moths (n ≥ 100 specimens captured) did vary in abundance among habitats in both landscapes (p < 0.05), with poletimber stands, riparian forest and upland forest selected, and pasture, forest edge, sawtimber and sapling stands avoided by at least one family of moths. Density and richness of woody plant species were correlated with the occurrence of moths at sampling sites. We recommend maintaining habitat heterogeneity around roosts of the Ozark big-eared bat to encourage an abundance and richness of moth prey, and suggest that forested riparian corridors are important habitat elements for Ozark big-eared bats foraging in fragmented landscapes.     

Impact of deliquescence on the chemical stability of vitamins B1, B6, and C in powder blends

Single vitamin ingredients and blends in premixes are widely used in the food and supplement industries and are predominantly in powder form. To meet label claims and/or determine appropriate overages, it is important to characterize the stability of these ingredients. Although moisture is a known promoter of instability in powder blends, the combined effects of storage relative humidity (RH), formulation, and deliquescence on the stability of these systems are not well-characterized. The objective of this study was to determine the effect of deliquescence on the stability of vitamins B 1, B 6, and C and their mixtures. Deliquescence points (RH 0s) for all formulations were determined by moisture sorption analysis. Single, binary, ternary, and quaternary mixtures of thiamin HCl, pyridoxine HCl, sodium ascorbate, and fructose were stored in RH-controlled environmental chambers between 43 and 98% RH at 22 degrees C for up to 12 weeks. Vitamin stability was determined by high-performance liquid chromatography (HPLC). Formulation and storage RH significantly affected vitamin stability. Thiamin and ascorbate degradation were significantly promoted above the RH 0, while pyridoxine was least affected by storage RH. The deliquescence lowering phenomenon enhanced moisture sorption of blends at RHs below the RH 0s. Ascorbate enhanced thiamin degradation. Therefore, formulation, storage conditions, and the relation of these to deliquescence points may affect the shelf life, quality, and functionality of vitamin blends and should be considered in product development, processing, storage, and use.     

Phacoemulsification and intraocular lens implantation in a Canada lynx with phacoclastic uveitis

A 4-year-old male Canada lynx (Lynx canadensis) was referred to the ophthalmology service at the University of Saskatchewan with a 7-month history of cataract and chronic phacoclastic uveitis secondary to penetrating trauma from a lynx claw. Ophthalmic examination of the right eye revealed a corneal scar, marked aqueous flare, extensive fibrovascular membranes extending from the iris to the lens, anterior and posterior synechiae, immature cataract, and anterior vitritis; the fundus was not visible. Phacoemulsification surgery and intraocular lens implantation using a custom lens of D+46 and 14 mm (An-vision, West Jordan, Utah, USA) was performed. Post-operative medications included sub-conjunctival injections of atropine, cefazolin, and triamcinolone, and oral doxycycline and prednisolone. At the 5-month follow-up, the uveitis was controlled, and a normal fundus was visualized; at 21 mo, the eye remained comfortable and visual. This is the first case report to describe phacoemulsification in a wild felid as a treatment for a traumatic cataract and severe phacoclastic uveitis.Key clinical message:Despite chronic phacoclastic uveitis, phacoemulsification surgery can provide a positive outcome for mature wild felids with traumatic lens rupture, even when topical treatment cannot be administered.     

Perceptions and priorities of owners of dogs with heart disease regarding quality versus quantity of life for their pets

OBJECTIVE: To describe the relative importance of pets' quality versus quantity of life among owners of dogs with heart disease. DESIGN: Prospective questionnaire-based clinical study. SAMPLE POPULATION: Owners of 201 dogs with heart disease. PROCEDURES: Owners each completed a questionnaire that was designed to ascertain the relative importance of quality versus quantity of life for their pet and to assess the owners' willingness to trade survival time for quality of life, if that were possible. Analyses were performed to evaluate factors associated with owner willingness to trade time for quality of life. RESULTS: Most owners (170/197 [86%]) were willing to trade survival time for quality of life for their heart disease-affected dogs; of those owners, 88 (52%) were willing to trade 6 months. Owners were highly concerned with detection of perceived pet suffering and their pet's ability to interact with them. Owners whose pets had respiratory difficulty or fainting episodes and were treated on an outpatient basis had a greater willingness to trade survival time than owners of dogs that were treated on an emergency basis. Among owners willing to trade time for quality of life, younger owners and those whose pets had fainting episodes were willing to trade the most amount of time. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that quality of life is highly important to owners of dogs with heart disease. Owners' priorities partly depend on owner age and the pet's clinical circumstances; ongoing client-veterinarian communication is important to optimize treatment success as perceived by owners.     

Kinetics of moisture-induced hydrolysis in powder blends stored at and below the deliquescence relative humidity: investigation of sucrose-citric acid mixtures

Previous studies have shown that deliquescent organic compounds frequently exhibit chemical instability when stored in environmental conditions above their deliquescence relative humidity (RH). The goal of the current study was to investigate the effect of atmospheric moisture on the long-term chemical stability of crystalline sucrose-citric acid mixtures following storage at RHs at and below the mutual deliquescence relative humidity (MDRH). Interestingly, it was found that sucrose hydrolysis can occur below the MDRH of 64% and was observed for samples stored at 54% RH. However, hydrolysis was not seen for samples stored at 33 or 43% RH. The rate of sucrose hydrolysis could be modeled by taking into account the rate and extent of moisture uptake, which in turn was dependent on the composition of the powder and the storage RH. A reaction mechanism initiated by capillary condensation and involving additional deliquescence lowering by the degradation products formed as a result of sucrose hydrolysis (glucose and fructose) was proposed.     

Evaluation of Different Extraction Methods for the Assessment of Heavy Metal Bioavailability in Various Soils

The main objective of this study was to compare the effectiveness of different methods (heavy metals in pore water (PW), diffusive gradients in thin films (DGT), diethylene triamine pentaacetic acid (DTPA) extraction, and total heavy metals (THM) in soil) for the assessment of heavy metal bioavailability from soils having various properties and heavy metal contents. The effect of soil heavy metal pollution on shoot yield and sulfatase enzyme activity was also studied. Wheat (Triticum aestivum) was grown in different soils from Spain (n?=?10) and New Zealand (n?=?20) in a constant environment room for 25 days. The bioavailabilities of Cd, Cr, Cu, Ni, Pb, and Zn were assessed by comparing the metal contents extracted by the different methods with those found in the roots. The most widely applicable method was DGT, as satisfactory Cu, Ni, Pb, and Zn root concentrations were obtained, and it was able to distinguish between low and high Cr values. The analysis of the metal concentrations in PW was effective for the determination of Cr, Ni, and Zn content in root. Copper and Pb root concentrations were satisfactorily assessed by DTPA extraction, but the method was less successful with determining the Ni and Cr contents and suitable just to distinguish between high and low concentrations of Zn. The THM in soil method satisfactorily predicted Cu and Pb root concentrations but could only be used to distinguish between low and high Cr and Zn values. The Cd root concentration was not successfully predicted for any of the used methods. Neither shoot yield nor sulfatase enzyme activity was affected by the metal concentrations.     

The impact of introduced signal crayfish Pacifastacus leniusculus on stream invertebrate communities

• 1. The effect of a newly introduced population of signal crayfish (Pacifastacus leniusculus) on a riverine invertebrate community in the River Clyde, Scotland, is examined. Five hypotheses related to crayfish impact on the invertebrate community are tested by comparing sites containing signal crayfish with similar sites in the same river which have not yet been colonized.
• 2. The hypothesis that crayfish significantly reduce the total numbers of invertebrates in the community was supported by this study, with invertebrate density in areas containing signal crayfish around 60% of that with no observed crayfish.
• 3. The hypothesis that crayfish presence affects some groups more than others was also supported. Plecoptera, Chironomidae, Diptera and Hirudinea, in particular, showed evidence of reduced species numbers in areas containing crayfish, and Plecoptera, Hirudinea, Tricladida and Hydracarina showed evidence of reduced densities. Community diversity and richness was also lower at sites containing crayfish.
• 4. Neither the hypothesis that overall invertebrate biomass would be lower at sites with crayfish present nor the hypothesis that individual invertebrate size would be lower at sites with crayfish was supported.
• 5. Overall the study indicates that introduced signal crayfish can significantly and fundamentally modify fluvial macroinvertebrate community structure.

Copyright © 2006 John Wiley & Sons, Ltd.