Comparative inhibition of boll weevil,golden shiner,and white rat cholinesterases by selected photoalteration products of parathion

The effect of seven photoalteration products of parathion and the parent compound itself on fish (golden shiner), mammal (white rat), and insect (boll weevil) cholinesterases are compared. The white rat cholinesterase was found to be more susceptible to inhibition by photoalteration products of parathion than the golden shiner and boll weevil cholinesterases. In every instance in which inhibition occurred, the phosphate analogs were determined to be more potent anticholinesterase agents than the corresponding phosphorothioate analogs.     

Laminar growth of ultrathin metal films on metal oxides: Co on hydroxylated alpha-Al2O3(0001)

Metals deposited in vacuum on metal oxides such as alumina normally grow as three-dimensional clusters because of weak adatom-substrate interactions. This tendency hinders our ability to form interfaces of ultrathin, laminar metal films on oxides for use in microelectronics and other technologies where nanostructural control is desired. We present experimental and theoretical results showing that room temperature Co deposition on fully hydroxylated clean sapphire (alpha-Al2O3) produces a surface chemical reaction that leads to laminar growth, despite a large mismatch in lattice constants. This process should be applicable to a wide range of metals and metal oxides.     

Regional variations in percutaneous absorption of methimazole: an in vitro study on cat skin

The use of transdermal gel medications in cats has become popular in veterinary medicine due to the ease of administration compared to oral medication. The research to support systemic absorption of drugs after transdermal gel administration and the preferred skin region to apply these drugs in cats is limited. The aim of this study was to characterize the effect of different skin regions on the percutaneous absorption pharmacokinetics of a commercially available transdermal methimazole after a finite dose was applied to feline skin in vitro. A commercial formulation of methimazole (10 mg) was applied to four skin regions (the inner stratum corneum of the ear, groin, neck, and thorax regions) from six cats. The receptor medium was sampled up to 36 h postapplication, and methimazole concentrations were measured using high‐performance liquid chromatography. Methimazole was absorbed more completely across the pinnal skin, compared to the groin, neck, and thorax (P < 0.001), which justifies application to the pinna to maximize efficacy and also to minimize the effects of grooming.     

THE EFFECTS OF LEVEL OF NITROGEN FERTILIZER ON BEEF PRODUCTION FROM GRAZED PERENNIAL RYEGRASS/WHITE–CLOVER PASTURES

The treatments in this summer–grazing experiment were designed as a 3X3 factorial; 3 levels of nitrogenous fertilizer, supplying 0, 336 and 672 kg N/ha per annum, and 3 stocking rates. The fertilizer was applied in 6 to 8 dressings at intervals of 3 to 4 weeks. The animals used were fattening Hereford X Friesian steers. The stocking rates were calculated on the basis of data available on herbage production under N and irrigation treatments and varied according to the level of N input. The experiment was laid out in 6 randomized blocks, which were grazed in rotation. Blocks were removed from the grazing cycle in spring and early summer of each of the 3 years (1962—-4) over which the experiment was conducted and cut for conservation: yields were recorded. Details are given of: grazing management; results of studies of soil–N levels; the quantities of herbage removed for conservation: the quantity, chemical and botanical composition of the herbage available for grazing; and herbage consumption.     

Segmental hemiatrophy in a dog

Congenital asymmetric development, resulting in a small right thoracic limb, was diagnosed in a dog. The limb was anatomically normal. The lesion closely resembled hemiatrophy. Congenital asymmetric development should be considered in the differential diagnosis of limb length discrepancies. Treatment is required only in cases of extreme discrepancy between the normal and affected limb.     

Erythropoiesis and erythrocytic survival in dogs with cyclic hematopoiesis.

Erythrocytic survival and ferrokinetic studies were carried out in dogs with cyclic hematopoiesis. The serum iron values varied during different phases of the cycle. The highest values occurred when the bone marrow predominantly contained granulocytic cells. The erythrocytic survival and the remainder of the ferrokinetic variables were comparable to those in normal dogs of a similar age.     

Monitoring of water erosion on arable farms in England and Wales, 1989–90

Abstract. Water erosion was recorded between mid-October and mid-December 1989 in 31 out of 73 erosion-susceptible arable fields being monitored in England and Wales. Most fields were drilled to winter cereals. Tramlines and wheelings were the factors most commonly linked with initiation of erosion, particularly where runoff was concentrated on valley floors or headlands. Lack of crop cover (< 15%) was also an important factor at a number of sites; 25–30% ground cover was generally sufficient to protect the soils from erosion. Erosion was initiated by rainfall events of 15 mm or more in a 24 h period, with a maximum intensity greater than 4 mm/h. A large erosion event in south-west England was associated with 33 mm of rainfall in 4.25 h, with a maximum intensity of 22 mm/h.     

Hip luxation in a woodchuck (Marmota monax): successful treatment by closed reduction and a modified Ehmer sling.

An elastic tape sling successfully maintained reduction of a craniodorsal right coxofemoral luxation in a woodchuck (Marmota monax). No complications were encountered during the 14 days that the sling was in place. The animal remained normal through the following 8 mo.     

A new modified live equine influenza virus vaccine: phenotypic stability, restricted spread and efficacy against heterologous virus challenge.

Flu Avert IN vaccine is a new, live attenuated virus vaccine for equine influenza. We tested this vaccine in vivo to ascertain 1) its safety and stability when subjected to serial horse to horse passage, 2) whether it spread spontaneously from horse to horse and 3) its ability to protect against heterologous equine influenza challenge viruses of epidemiological relevance. For the stability study, the vaccine was administered to 5 ponies. Nasal swabs were collected and pooled fluids administered directly to 4 successive groups of na?ve ponies by intranasal inoculation. Viruses isolated from the last group retained the vaccine's full attenuation phenotype, with no reversion to the wild-type virus phenotype or production of clinical influenza disease. The vaccine virus spread spontaneously to only 1 of 13 nonvaccinated horses/ponies when these were comingled with 39 vaccinates in the same field. For the heterologous protection study, a challenge model system was utilised in which vaccinated or na?ve control horses and ponies were exposed to the challenge virus by inhalation of virus-containing aerosols. Challenge viruses included influenza A/equine-2/Kentucky/98, a recent representative of the 'American' lineage of equine-2 influenza viruses; and A/equine-2/Saskatoon/90, representative of the 'Eurasian' lineage. Clinical signs among challenged animals were recorded daily using a standardised scoring protocol. With both challenge viruses, control animals reliably contracted clinical signs of influenza, whereas vaccinated animals were reliably protected from clinical disease. These results demonstrate that Flu Avert IN vaccine is safe and phenotypically stable, has low spontaneous transmissibility and is effective in protecting horses against challenge viruses representative of those in circulation worldwide.