Experimental production of dermatitis in sheep with Pseudomonas aeruginosa

SUMMARY The attachment, to sheep skin, for 4 days, of control wool pads saturated with sterile culture medium which contained a bacteriostat, induced only a mild dermatitis, whereas wool pads saturated with Pseudomonas aeruginosa culture induced a subacute dermatitis characterised by scaling, microabscess formation and seropurulent exudate. Changes similar to the latter were observed in skin affected by natural fleece-rot which developed spontaneously after 7 days of artificial wetting and in which P. aeruginosa was the predominant species of bacteria. An exacerbatory, if not causal, role for this organism is suggested in the development of the dermatitis associated with fleece-rot and in the exudation of seropurulent material, a step essential in the development of body strike.     

DIFFUSION COEFFICIENTS FOR TWO TRIAZINE HERBICIDES IN SIX SOILS

Summary. Diffusion of the triazine herbicides propazine and prometryne was studied in six soils. Apparent diffusion coefficients were calculated from the distribution of herbicide in a column of soil after diffusion from one half of the column for a known time. The magnitude of the diffusion coefficients varied from 1·5 × 10^?9 cm² sec^?1 for propazine in a sandy soil to 3·1 × 10^?9 cm² sec^?1 for prometryne in an organic soil. Under the conditions of measurement, the diffusion coefficients decreased in proportion to the extent of adsorption. Calculations were made to determine over what distances diffusion could be of importance in the movement of these herbicides. Coefficients de diffusion de deux triazines herbicides dans six sols Résumé. La diffusion de deux triazines herbicides, la propazine et la prometryne a étéétudiée dans six sols. Les coefficients de diffusion apparente furent calculés selon la distribution de I'herbicide dans une colonne de sol, aprés diffusion à partir de la moitié de la colonne pendant un temps connu. Les coefficients de diffusion variérent de 1,5 × 10^?7cm² see^?1 pour la propazine dans un sol sableux, á 3,1 × 10^?9 cm² sec^?2 pour la prométryne dans un sol organique. Dans les conditions oú les mesures furent effectuées, les coefficients de diffusion diminuérent en proportion de 1′étendue de l'adsorption. Des calculs ont été effectués pour detérminer au-delá de quelles distances la diffusion pouvait presenter une importance dans le mouvement de ces herbicides. Difftisions-KoeffizienUnfur zwei Trtazin-Deriaate in sechs Böden Zusammenfassung. Die Diffusion der beiden Triazin-Derivate Propazin und Prometryn wurde in sechs Böden untersucht. Die Diffusions-Koeffizienten wurden aus der Verteilung des Herbizids in einer Bodensaule nach Diffusion aus der einen Säulenhalfte in einer bestimmten Zeit errechnet. Die Grösse der Diffusions-Koeffizienten variierte von 1,5 × 10^?7 cm²× sec^?1 bei Propazin in einem Sandboden bis 3,1 × 10^?9 cm²× sec^?1 bei Prometryn in einem Humus-Boden. Unter den gegebenen Versuchsbedingungen nahmen die Diffusions-Koeffizienten in Abhángigkeit von der Stärke der Adsorption ab, Es wurden Berechnungen darüber angestellt, über welche Entfernungcn die Diffusion dieser Herbizide im Boden eine Rolle spielen könnte.     

Weed control in conventional and herbicide tolerant winter oilseed rape (Brassica napus) grown in rotations with winter cereals in the UK

Two winter oilseed rape (Brassica napus) cultivars, tolerant to glyphosate and glufosinate, were compared with a conventional cultivar at three sites over 4 years, in 3‐year crop rotations in the UK. The winter oilseed rape was grown in Years 1 and 4, with winter cereals, which received uniform herbicide treatments, in the intervening years. The second winter oilseed rape treatments were applied to randomised sub‐plots of the original plots. Weed densities were recorded in autumn and spring and weed biomass was measured in summer. At most sites, there was only one application of glufosinate or glyphosate, whereas two products were often used on the conventional variety. The timing of glyphosate and glufosinate application was, on average, 34 days later than that of the conventional broad‐leaved weed control treatments. Overall weed control, across all sites and years, was not statistically different between the conventional, glyphosate and glufosinate treatments. However, glyphosate achieved higher control of individual weed species more frequently than the other treatments. Glufosinate and the conventional treatments were similar in performance. The treatments in Year 1 sometimes affected weed populations in the subsequent cereal crops and, in rare instances, those in the rape in Year 4. Carry‐over effects were small after most treatments. In general, weed survival was greater in the oilseed rape crops, irrespective of the treatment, than it was in the intervening cereal crops.     

Traumatic Coxofemoral Luxation In Dogs Results of Repair

The medical records of 171 dogs with traumatic hip luxations were examined. German shepherds, mixed breeds, and poodles were significantly overrepresented. The mean age of the patients at the time of diagnosis was 4.4 years (range 5 months to 14 years). Vehicular trauma caused 83% of the 133 luxations where the etiology was known; 53% had at least one other diagnosed traumatic injury. Long-term results were obtained from owner questionnaires (25 dogs) or clinical and radiographic examinations (11 hip joints). The short-term recurrence rate after closed reduction (47.3%) was higher than that after surgical reduction using any of the three surgical techniques most frequently used here (9.5, 12.5, and 14.3%), even when the operation was performed after failure of a closed reduction (11.8%). Excluding dogs that had a femoral head ostectomy, 68% (17 of 25) of the dogs had a normal gait, 16% had only a mild lameness, and 16% had more severe lameness when evaluated on an average of 31 months after repair. Of 11 hip joints radiographed on an average of 25 months following repair, five had no radio-graphic abnormalities related to the luxation and six showed one or more of the following: periosteal new bone formation, femoral head subluxation, partial resorption of the femoral head, periarticular osteophytes, and subchondral bone erosion. Closed reduction should be the initial treatment of choice in uncomplicated luxations even though the rate of reluxation is high, because it avoids the need for surgery in approximately one half of affected dogs and does not increase the recurrence rate following subsequent surgical reduction.     

Standard Methods for the Assessment of Sunn Pests of Wheat and for Crop Losses caused by them

In an attempt to standardize methods of assessment of Eurygaster spp. and Aelia spp., some methods published in USSR, Romania and Turkey are reviewed and details given. These are: 1) counting overwintering adults in quadrats or along a line; 2) counting old adults in quadrats or by sweep net after migration; 3) counting nymphs in quadrats. Methods of assessing crop loss caused are: 1) counting attacked stems of young wheat; 2) counting attacked ears; 3) identification and counting of attacked grain at harvest; 4) caging different numbers of nymphs and adults, and taking yields, grain weight, germination etc.; 5) assessing the effect on baking quality of flour etc. The effects of different numbers of insects per m² on yield are given. It is suggested that standardization of such methods would lead to improved cooperative studies between different countries.