Integrating multiple techniques to identify stock boundaries of common bottlenose dolphins (Tursiops truncatus)

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Status and the potential for extinction of the largetooth sawfish Pristis pristis in the Atlantic Ocean

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Complex dynamics may limit prediction in marine fisheries

Complex nonlinear dynamics in marine fisheries create challenges for prediction and management, yet the extent to which they occur in fisheries is not well known. Using nonlinear forecasting models, we analysed over 200 time series of survey abundance and landings from two distinct ecosystems for patterns of dynamic complexity (dimensionality and nonlinear dynamics) and predictability. Differences in system dimensionality and nonlinear dynamics were associated with time series that reflected human intervention via fishing effort, implying the coupling between human and natural systems generated dynamics distinct from those detected in the natural resource subsystem alone. Estimated dimensionality was highest for landings and higher in abundance indices of unfished species than fished species. Fished species were more likely to display nonlinear dynamics than unfished species, and landings were significantly less predictable than abundance indices. Results were robust to variation in life history characteristics. Dynamics were predictable over a 1‐year time horizon in seventy percent of time series, but predictability declined exponentially over a 5‐year horizon. The ability to make predictions in fisheries systems is therefore extremely limited. To our knowledge, this is the first cross‐system comparative study, and the first at the scale of individual species, to analyse empirically the dynamic complexity observed in fisheries data and to quantify predictability broadly. We outline one application of short‐term forecasts to a precautionary approach to fisheries management that could improve how uncertainty and forecast error are incorporated into assessment through catch limit buffers.     

Formation of strecker aldehydes from polyphenol-derived quinones and alpha-amino acids in a nonenzymic model system

Fruits and vegetables contain naturally occurring polyphenolic compounds that can undergo enzyme-catalyzed oxidation during food preparation. Many of these compounds contain catechol (1,2-dihydroxybenzene) moieties that may be transformed into o-quinone derivatives by polyphenoloxidases and molecular oxygen. Secondary reactions of the o-quinones include the Strecker degradation of ambient amino acids to form flavor-important volatile aldehydes. The purpose of this work was to investigate the mechanism of the polyphenol/o-quinone/Strecker degradation sequence in a nonenzymic model system. By using ferricyanide ion as the oxidant in pH 7.17 phosphate buffer at 22 degrees C, caffeic acid, chlorogenic acid, (+) catechin, and (-) epicatechin were caused to react with methionine and phenylalanine to produce Strecker aldehydes methional and phenylacetaldehyde in 0.032-0.42% molar yields (0.7-10 ppm in reaction mixtures). Also, by employing l-proline methyl ester in a reaction with 4-methylcatechol, a key reaction intermediate, 4-(2'-carbomethoxy-1'-pyrrolidinyl)-5-methyl-1,2-benzoquinone (7), was isolated and tentatively identified.     

Rapid detection of Arthroderma vanbreuseghemii in rabbit skin specimens by PCR-RFLP

Three commercial rabbit farms independently reported suspected dermatophyte infections during 2004. Cultures confirmed that the infection was caused by the zoophilic Tricophyton mentagrophytes, while mating studies and sequencing of the internal transcribed spacer (ITS)1/4 polymerase chain reaction products, directly amplified from skin lesions and from pure culture isolates, established its Arthroderma vanbreuseghemii lineage. Subsequently, the corresponding DdeI restriction profiles of the ITS1/4 PCR products matched one of the two published T. mentagrophytes complex profiles. Sequence analysis of the published ITS sequences predicted distinct DdeI restriction sites for Arthroderma benhamiae and A. vanbreuseghemii, while all DdeI-generated restriction fragment length polymorphisms of the rabbit isolates were identical to those of A. vanbreuseghemii. The proposed procedure can be used for rapid dermatophyte detection and presumptive T. mentagrophytes identification.     

Effects of oxymorphone and hydromorphone on the minimum alveolar concentration of isoflurane in dogs

OBJECTIVES: To quantify the change in the minimum alveolar concentration (MAC) of isoflurane (ISO) associated with oxymorphone (OXY) or hydromorphone (HYDRO) in dogs. DESIGN: Randomized crossover study with at least 1 week between assessments. ANIMALS: Six young, healthy, mixed-breed dogs (1-3 years old), weighing 24.7 +/- 4.70 kg. METHODS: Following mask induction, anesthesia was maintained with ISO in 100% O(2) using mechanical ventilation. The dogs received 0.05 mg kg(-1) OXY, 0.1 mg kg(-1) HYDRO, or 1 mL saline (control) IV. Following equilibration (15 minutes) at each percentage ISO tested, a supramaximal electrical stimulus was applied to the toe web and the response was assessed. Two separate MAC determinations were carried out during 4.5 hours of anesthesia, with completion of the evaluations at 1.5-2 and 4-4.5 hours after drug administration. A two-factor anova was used to determine whether there was a time or treatment effect on MAC and a Tukey test compared the drug effects at each time. Significance is reported at p < 0.05. RESULTS: The mean MAC values (+/-SD) were 1.2 +/- 0.18 and 1.2 +/- 0.16% for control, 0.7 +/-0.15 and 1.0 +/- 0.15% for OXY, and 0.6 +/- 0.14 and 0.8 +/- 0.17% for HYDRO. The initial MAC with OXY and the MAC determined at both times with HYDRO were significantly different from the control MAC values. CONCLUSIONS: Both OXY and HYDRO significantly reduced the MAC of ISO in dogs at 2 hours. At approximately 4.5 hours, HYDRO had a significant MAC-sparing effect, whereas OXY did not. CLINICAL RELEVANCE: Although both OXY and HYDRO resulted in a significant reduction in the MAC of ISO at approximately 2 hours, HYDRO may be preferred for procedures of long duration and rarely needs repeated dosing before 4.5 hours.     

Fungal osteomyelitis of the axial border of the proximal sesamoid bones in a horse

CASE DESCRIPTION: A 12-year-old Standardbred gelding was referred for swelling of the right metacarpophalangeal joint. CLINICAL FINDINGS: Ultrasonography of the right metacarpal area revealed hypoechoic areas in the right digital sheath and metacarpophalangeal joint consistent with synovial effusion. Radiography of the right metacarpophalangeal joint revealed lysis of the axial border of the proximal sesamoid bones. Aspergillus fumigatus was detected on fungal culture of synovial fluid. TREATMENT AND OUTCOME: Regional limb perfusion (150 mg of amikacin in 60 mL of saline [0.9% NaCl] solution perfused for 30 minutes) was performed 2 and 4 days after admission. Itraconazole (5 mg/kg [2.27 mg/lb], PO, q 24 h) was administered for approximately 9 weeks. Joint lavage with amikacin (500 mg) in 1 L of saline solution was performed 4 times. Three months after discharge, the owner reported that the horse was mildly lame during trotting but was moving freely and comfortably during all gaits and had gained a considerable amount of weight. Because the osteoarthritis was not expected to improve and because it was recommended that the horse not return to purposeful exercise, the owner decided to retire the horse from racing. CLINICAL RELEVANCE: Various diagnostic imaging methods and fungal cultures are useful for diagnosing fungal osteomyelitis of the axial borders of the proximal sesamoid bones in horses. Fungal osteomyelitis of the sesamoid bones and erosive arthritis should be considered as a differential diagnosis for horses in which corticosteroids have been administered intra-articularly.     

Agreement between computed tomography, magnetic resonance imaging, and surgical findings in dogs with degenerative lumbosacral stenosis

OBJECTIVE: To assess the extent of agreement between computed tomography (CT), magnetic resonance imaging (MRI), and surgical findings in dogs with degenerative lumbosacral stenosis. DESIGN: Observational study. ANIMALS: 35 dogs with degenerative lumbosacral stenosis. PROCEDURES: Results of preoperative CT and MRI were compared with surgical findings with respect to degree and location of disk protrusion, position of the dural sac, amount of epidural fat, and swelling of spinal nerve roots. RESULTS: A lumbosacral step was seen on radiographic images from 22 of 32 (69%) dogs, on CT images from 23 of 35 (66%) dogs, and on MR images from 21 of 35 (60%) dogs. Most dogs had slight or moderate disk protrusion that was centrally located. There was substantial or near perfect agreement between CT and MRI findings in regard to degree of disk protrusion (kappa, 0.88), location of disk protrusion (0.63), position of the dural sac (0.89), amount of epidural fat (0.72), and swelling of spinal nerve roots (0.60). The degree of agreement between CT and surgical findings and between MRI and surgical findings was moderate in regard to degree and location of disk protrusion (kappa, 0.44 to 0.56) and swelling of spinal nerve roots (0.40 and 0.50). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicate that there is a high degree of agreement between CT and MRI findings in dogs with degenerative lumbosacral stenosis but that the degree of agreement between diagnostic imaging findings and surgical findings is lower.     

Streptococcus equi meningoencephalomyelitis in a foal

CASE DESCRIPTION: A 4-month-old American Paint Horse colt was evaluated because of acute onset of ataxia, left-sided head tilt, and fever and a recently noticed heart murmur. Upper respiratory tract infection caused by Streptococcus equi subsp equi had been diagnosed at 3 months of age. CLINICAL FINDINGS: Hematologic abnormalities included leukocytosis, mature neutrophilia, monocytosis, and mild anemia. Analysis of a CSF sample revealed high total protein concentration and total nucleated cell count; nucleated cells consisted mainly of degenerate neutrophils. Results of a real-time PCR assay were positive for S equi subsp equi, and a diagnosis of S equi subsp equi meningoencephalomyelitis was made. TREATMENT AND OUTCOME: Treatment included administration of potassium penicillin and fluids, but the foal developed uroperitoneum and was subsequently euthanized. Postmortem examination revealed meningoencephalomyelitis, and S equi subsp equi was cultured from a brain aspirate. Additional findings included suppurative cystitis with rupture and neutrophilic myocarditis. CLINICAL RELEVANCE: Findings suggest that S equi subsp equi meningoencephalomyelitis should be considered in the differential diagnosis for foals with neurologic signs that have a history of strangles or exposure to affected horses.     

Effects of dietary vitamin E and fat supplementation on pork quality

The effects of dietary vitamin E (VE, alpha-tocopherol acetate) and fat supplementation on growth and carcass quality characteristics, oxidative stability of fresh and cooked pork patty in storage, fatty acid profiles of muscle and adipose tissue, and VE concentrations of plasma, muscle, and adipose tissue were studied. Six hundred pigs were allocated to 1 of 6 diets and fed for 63 d in a 3 x 2 factorial design. The dietary treatments included 3 fat levels (normal corn, high oil corn, high oil corn plus added beef tallow) and 2 levels of VE supplementation (40 IU/kg, normal VE supplementation; and 200 IU/kg, high VE supplementation). At 113 kg of BW, 54 pigs were slaughtered as a subsample to evaluate dietary effects on pork quality. Growth performance and meat quality characteristics did not differ (P > 0.05) among treatment groups. The high level of VE supplementation had a beneficial effect on the oxidative stability of pork as indicated by thiobarbituric acid reactive substance (TBARS) values. Lean tissue had lower (P < 0.05) TBARS in the group fed the high VE than in those fed the normal VE level. The TBARS values differed among storage periods (0 to 6 d) and also between fresh and cooked ground ham. Fat type did not significantly affect total saturated and unsaturated fatty acids proportions in the neutral and polar fraction of muscle. Adding VE acetate led to greater (P < 0.05) monounsaturated and total unsaturated fatty acid proportions in neutral lipids of muscle and adipose tissues. Increasing dietary levels of VE acetate increased the concentration of VE in plasma and muscle. These results indicate that dietary VE acetate supplementation increased (P < 0.05) lipid stability and the VE concentration of muscle.