Treatment with ivermectin of sarcoptic mange in pigs

Ivermectin injectable solution (1% w/v) was highly effective against Sarcoptes scabiei var suis when administered subcutaneously once to swine at 300 mcg/kg body weight. There were significantly (P < 0.05) fewer Sarcoptes mange mites counted on pigs treated with ivermectin than on untreated pigs at each count up to day 56 after treatment. The results indicate ivermectin should provide an efficient, practical means of control of sarcoptic mange in intensive piggeries.     

SENSITIVITY OF RADIOGRAPHIC DETECTION OF LUNG METASTASES IN THE DOG

Thoracic radiographs were taken in right lateral recumbent (RLR), left lateral recumbent (LLR), and ventrodorsal (VD) projections in 80 dogs with known or suspected malignant tumors. Radiographs in each projection were interpreted, independently of those in the other two projections, by four veterinary radiologists, and classified as positive or negative for one or more lung metastases. The four radiologists then met, to agree on a diagnosis for each patient by simultaneously reviewing all three views. This panel diagnosis became the standard for subsequently classifying individual views as either true positive or true negative. As determined by a consensus of the panel, 25 dogs had at least one positive thoracic radiograph.
The three radiographic projections differed in sensitivity for the detection of lung metastases. In this study, the RLR view was the most sensitive, and the VD view the least sensitive. The sensitivity of detection improved significantly with multiple readers. From these data we recommend that, for detection of lung metastases in the dog, the RLR view be included in any diagnostic protocol; a minimum of two readers be used; and a three-view protocol be used if only one reader is available.     

Advances in pasture plant breeding for animal productivity and health

Plant breeding has had a substantial effect on the productivity and health of ruminant animals in New Zealand by improving the quantity, quality and reliability of grazed temperate pastures. Genetic changes have affected annual pasture productivity, seasonal growth, digestibility, protein/energy balance, level of rumen undegradable protein, leaf properties affecting intake, resistance to foliar diseases, and reductions in compounds that have an adverse impact on the health, welfare and reproductive fertility of ruminant animals. Most plant improvement programmes have achieved genetic gains in excess of 1% per year for a variety of target traits, and these gains are likely to continue given the high genetic variation available within forage plants. Significant heritable variation exists to improve forage quality, particularly for soluble carbohydrate and fibre fractions in grasses, and in the rate at which these change during the season. Deleterious animal health and welfare effects can be alleviated through the use of non-toxic endophytes in grasses, that do not produce lolitrem B and ergovaline. Use of improved cultivars, with the appropriate management, can add value to animal products.     

Mars-like soils in the Atacama Desert, Chile, and the dry limit of microbial life

The Viking missions showed the martian soil to be lifeless and depleted in organic material and indicated the presence of one or more reactive oxidants. Here we report the presence of Mars-like soils in the extreme arid region of the Atacama Desert. Samples from this region had organic species only at trace levels and extremely low levels of culturable bacteria. Two samples from the extreme arid region were tested for DNA and none was recovered. Incubation experiments, patterned after the Viking labeled-release experiment but with separate biological and nonbiological isomers, show active decomposition of organic species in these soils by nonbiological processes.     

Correlations between ground and excited state spectra of a quantum Dot

The ground and excited state spectra of a semiconductor quantum dot with successive electron occupancy were studied with linear and nonlinear magnetoconductance measurements. A direct correlation was observed between the mth excited state of the N-electron system and the ground state of the (N + m)-electron system for m up to 4. The results are consistent with a single-particle picture in which a fixed spectrum of energy levels is successively filled, except for a notable absence of spin degeneracy. Further departures from the single-particle picture due to electron-electron interaction were also observed. Magnetoconductance fluctuations of ground states show anticrossings where wave function characteristics are exchanged between adjacent levels.     

A Legume Ethylene-Insensitive Mutant Hyperinfected by Its Rhizobial Symbiont

Development of the Rhizobium-legume symbiosis is controlled by the host plant, although the underlying mechanisms have remained obscure. A mutant in the annual legume Medicago truncatula exhibits an increase of more than an order of magnitude in the number of persistent rhizobial infections. Physiological and genetic analyses indicate that this same mutation confers insensitivity to the plant hormone ethylene for multiple aspects of plant development, including nodulation. These data support the hypothesis that ethylene is a component of the signaling pathway controlling rhizobial infection of legumes.