Evaluation of ionized and total serum magnesium concentrations in hyperthyroid cats

Hyperthyroidism can increase the renal excretion of magnesium and thus cause hypomagnesemia in various species. Anaerobically collected blood samples from 15 hyperthyroid and 40 normal, healthy cats were analyzed with an ion-selective electrode analyzer and a serum biochemical analyzer. There was no significant difference in ionized or total serum magnesium concentration between the 2 groups, but there was a significant difference (P = 0.004) in the ratio of ionized to total serum magnesium concentrations between the healthy cats and the hyperthyroid cats with thyroxine (T4) concentrations at or above the median. There was a significant correlation (r = 0.894, P = 0.000) between the ionized and total magnesium concentrations in the hyperthyroid cats. The hyperthyroid cats had a significantly lower (P = 0.003) total serum protein concentration than the healthy cats. A significant negative correlation (r = -0.670, P = 0.006) was detected between the ionized magnesium and logarithmically transformed total T4 concentrations in the hyperthyroid cats, which suggests that the severity of hyperthyroidism may contribute to a decrease in the ionized magnesium concentration.     

You can swim but you can't hide: the global status and conservation of oceanic pelagic sharks and rays

• 1. Fishing spans all oceans and the impact on ocean predators such as sharks and rays is largely unknown. A lack of data and complicated jurisdictional issues present particular challenges for assessing and conserving high seas biodiversity. It is clear, however, that pelagic sharks and rays of the open ocean are subject to high and often unrestricted levels of mortality from bycatch and targeted fisheries for their meat and valuable fins.
• 2. These species exhibit a wide range of life‐history characteristics, but many have relatively low productivity and consequently relatively high intrinsic vulnerability to over‐exploitation. The IUCN — World Conservation Union Red List criteria were used to assess the global status of 21 oceanic pelagic shark and ray species.
• 3. Three‐quarters (16) of these species are classified as Threatened or Near Threatened. Eleven species are globally threatened with higher risk of extinction: the giant devilray is Endangered, ten sharks are Vulnerable and a further five species are Near Threatened. Threat status depends on the interaction between the demographic resilience of the species and intensity of fisheries exploitation.
• 4. 4. Most threatened species, like the shortfin mako shark, have low population increase rates and suffer high fishing mortality throughout their range. Species with a lower risk of extinction have either fast, resilient life histories (e.g. pelagic stingray) or are species with slow, less resilient life histories but subject to fisheries management (e.g. salmon shark).
• 5. 5. Recommendations, including implementing and enforcing finning bans and catch limits, are made to guide effective conservation and management of these sharks and rays.

Copyright © 2008 John Wiley & Sons, Ltd.     

Potato Stem Cuttings to Study <Emphasis Type="Italic">Verticillium dahliae</Emphasis> Infection for Resistance Breeding and ‘omics’ Studies

Consistent and effective methods for early discrimination of pathogen resistance, and selection of times for tissue sampling, are important for experiments using global gene expression and metabolomics. Assays for resistance to the vascular pathogen Verticillium dahliae (Vd), the causal agent of Verticillium wilt (VW), are particularly difficult because escapes are common in field assays. Seedling dip assays offer a potential solution, but homogeneous populations are not typically available. As an alternative strategy, we have developed a protocol for studying spatiotemporal infection dynamics of Vd using potato stem cuttings. The protocol was validated using genotypes varying in resistance/susceptibility to Vd. Although there were no visual symptoms in the plants, stem sections were infested with Vd as early as 7 dpi. Symptoms were first observed in the most susceptible genotype at 10 dpi and became apparent on all test subjects at 14 dpi. The protocol has potential applications in resistance breeding and ‘omics’ studies where populations derived from true seeds are not available.     

The costs of multiple patch use by birds

Birds living in fragmented habitat may occupy territories comprising more than one patch. This paper uses a theoretical model to investigate the costs (in terms of time and energy) of crossing gaps between patches for birds feeding young in the nest, using the great tit (Parus major) as an example. When the proportion of foraging trips involving gap-crossing was small (25%), gaps of about 300–550 m (depending on body mass and flight speed) could be crossed without exceeding likely maximum sustainable daily energy expenditure (DEE_max). However, a penalty of time lost in crossing gaps of about one hour was incurred. For more gap-crossing (due to larger brood size and/or a greater proportion of gap-crossing trips), distances that could be crossed decreased rapidly to about 50–100 m and time lost increased to more than six hours. Crossing gaps at maximum range speed, rather than at the slower minimum power speed, reduced flight times by 42% and slightly reduced overall daily energy expenditure because the higher flight costs per minute were more than off-set by the shorter flight times. Smaller body mass (17 g versus 19 g) was advantageous for gap-crossing, the distances which could be crossed without exceeding DEE_max being almost doubled for the smaller mass. The influence of changes in wing morphology, fat load and prey load size on the energetics of gap-crossing were also considered. Although the model was constructed for a woodland bird, problems of time and energy expenditure associated with gap-crossing will affect many species which exploit patchy resources, especially when the spacing of the patches increases, for example due to habitat loss and modification. In landscapes where semi-natural habitat is highly fragmented and most surviving patches are small (e.g., many farming landscapes) the costs of multiple patch use may represent another mechanism by which habitat fragmentation reduces the reproductive potential of the inhabitants of habitat patches which are of acceptable or even good quality, but are small.     

Apparent digestibility of some nutrient sources by juvenile mud crab, Scylla serrata (Forskal 1775)

As part of preliminary work aimed at the development of a formulated diet for the mud crab, Scylla serrata, an experiment was conducted with juvenile mud crabs (95.65±2.17 g) to determine apparent digestibility coefficients (ADC) for cellulose, fish meal, shrimp meal, blood meal, soybean meal, wheat flour and cod liver oil. Apparent digestibility coefficients for dry matter (ADC_dm), energy (ADC_energy) and protein (ADC_protein) were in the ranges 70.0–95.7%, 77.4–97.1% and 57.7–97.9% respectively. Soybean meal had the highest ADC_dm and wheat flour had the lowest value (P<0.05), while the ADC_dm for fish meal, blood meal and shrimp meal were not different (P≥0.05). Similarly, soybean meal had the same ADC_energy as that of fish meal, but higher than those of cod liver oil, blood meal and shrimp meal (P<0.05). Moreover, the ADC_protein for blood meal or shrimp meal were not significantly different from fish meal (P≥0.05); nevertheless, they were lower than that of soybean meal and higher than that of wheat flour (P<0.05). Of significant interest was the ADC_dm (78.0%) and ADC_energy (77.4%) for cellulose, which indicates that plant‐based nutrient sources may well be a useful component of formulated diets for mud crabs.     

Clinical resolution of nasal aspergillosis following therapy with a homeopathic remedy in a dog

A 6 yr old, male, neutered Weimaraner was treated homeopathically for nasal aspergillosis after failing to respond to two treatments of topical (intranasal) clotrimazole and oral amoxicillin trihydrate/clavulanate potassium. Computed tomography, rhinoscopy, fungal culture, and cytology previously confirmed the diagnosis. At presentation for homeopathic treatment, the dog had aggressive left-sided sinusitis and rhinitis with destruction of nasal turbinates and severe bouts of epistaxis. Erosion and depigmentation of the nasal planum were evident. After two treatments with homeopathic aurum metallicum, resolution of clinical signs occurred and clearance of the aspergillosis organisms was documented by computed tomographic scan, rhinoscopy, and histopathology. Homeopathic aurum metallicum may be beneficial in treating cases of canine nasal aspergillosis.     

Comparative study of IFNγ and antibody tests for feline tuberculosis

This study describes the comparison of the cell-based interferon-gamma (IFNγ) test with serological rapid antibody tests (STAT-PAK and DPP VetTB) for the ante mortem testing of tuberculosis in domestic cats. The antibody specificities of rapid antibody test-positive cats were further discerned using multi-antigen print immunoassay. A total of 62 cats with culture-confirmed Mycobacterium bovis, Mycobacterium microti, Mycobacterium avium and Mycobacterium malmoense, as well as negative controls and dangerous-contact cats were tested. Tests were also applied longitudinally to one further cat undergoing TB chemotherapy for suspected M. bovis infection. Our data from this small study show excellent test specificity (100% for all tests) and encouraging levels of test sensitivity for M. bovis and TB Complex infections (IFNγ 70-100% depending upon test interpretation criteria; rapid tests both 90% for M. bovis infection and up to 46.2% for M. microti infection). The differential diagnosis of very pathogenic TB Complex (M. bovis, Mycobacterium tuberculosis), as opposed to less-pathogenic TB Complex (M. microti) was possible where positive responses to the protein cocktail ESAT6/CFP10 were observed (80% of M. bovis-infected cats in this study showed positive IFNγ responses to ESAT6/CFP10, while 20% had antibody responses to ESAT6/CFP10 using MAPIA). Finally, preliminary data from a longitudinal study of one M. bovis-exposed cat with a positive IFNγ test pre-treatment suggest that a decrease in bacterial burden may be reflected in the IFNγ response, and thus the IFNγ test may provide a monitor for TB chemotherapy.     

Functional analysis of a complementary DNA for the 50-kilodalton subunit of calmodulin kinase II

The calcium-calmodulin-dependent protein kinase II is a major component of brain synaptic junctions and has been proposed to play a variety of important roles in brain function. A complementary DNA representing a portion of the smaller 50-kilodalton subunit of the rat brain enzyme has been cloned and sequenced. The calmodulin-binding region has been identified and a synthetic analog prepared that binds calmodulin with high affinity in the presence of calcium. Like the 50-kilodalton kinase polypeptide, the concentration of the messenger RNA varies both neuroanatomically and during postnatal development of the brain. The broad tissue and species cross-reactivity of the complementary DNA suggests that the 50-kilodalton subunit found in rat brain is evolutionarily conserved and is the product of a single gene.     

Economic development and biotechnology: Public policy response to the farm crisis in Iowa

In periods of social crisis, policymakers become particularly vulnerable to interest groups mobilizing to compete for scarce funds. At this point, legislators are no longer able to address the specific needs of their primary constituency directly, but rather are forced to do so in pretext only. New, unfamiliar technologies provide ample ammunition for astute interest groups to take advantage of times of economic turmoil and maneuver for policy support through dramatic campaigns of “salesmanship.” By publicizing a crisis situation, dramatizing it effectively, and advertising an innovation as the solution to the crisis, legislators may be effectively persuaded to give priority to interest group pressures above and beyond those of the local constituency. Iowa's attempts to address the farm crisis through economic development strategies relying on biotechnology is examined in this paper. The results of extensive surveys of Iowa's legislators and farmers are examined and the consequences for Iowa's policy process of using biotechnology under the auspices of economic development are discussed.