DIAGNOSTIC SENSITIVITY OF BONE SCINTIGRAPHY FOR EQUINE STIFLE DISORDERS

Disorders of the stifle are a common cause of lameness in horses yet the accuracy of scintigraphy for diagnosis of stifle conditions is controversial. The aim of retrospective cross‐sectional study was to determine the diagnostic sensitivity (Se) of bone scintigraphy in detecting stifle disease and to determine if two orthogonal scintigraphic images improve diagnostic Se. Horses that underwent scintigraphic examination during a two‐year period were included. Horses were divided into two groups: group 1 (N = 23) had lameness that was localized to the stifle by intra‐articular analgesia and group 2 (N = 182) had lameness that was localized to a different location. Scintigraphic studies (one image or two images) were independently and retrospectively analyzed by two radiologists (R1 and R2). Sensitivity, specificity (Sp) and predictive values (PV), and were calculated for each type of study (one image or two images) and for each radiologist (R1 or R2). The Se to detect stifle disorders varied between radiologists (29.2% and 20.8%). The Sp was 84.5% and 88.3%. When two images were evaluated a decrease in the positive PV for both readers occurred. The Cohen kappa coefficient (κ) between readers was poor when one image (0.084) or two images (0.117) were evaluated. Findings from this study indicated that bone‐phase nuclear scintigraphy is reasonably specific but highly insensitive for detecting lameness originating from the stifle in a diverse population of both normal and affected horses. The addition of a caudal scintigraphic image acquisition did not improve diagnostic sensitivity.     

Assessment of field responses of potato cultivars and breeder seedlings to potato late blight epidemics

The response to potato late blight of 116 potato cultivars and breeding lines was determined in replicated trials conducted between 1980 and 1988. The index of area under the standardized disease progress curve (ASDPC), based on the cultivar Sebago, was used to rank the cultivars and to identify cultivars that had inconsistent disease responses over years. Most of the cultivars were susceptible to late blight; only 10 cultivars out of 66 currently available (including breeding lines) were judged more resistant than Sebago. Nine cultivars were identified as having inconsistent resistance over years. The index ASDPC was less variable than the relative area under the disease progress curve when the yearly disease conditions differed from the normal.     

Historical development and past ecological state of two danish shallow lakes

Background and Scope  

Lake sediment contains information on the historical development and former conditions of lakes, which is very useful when information about the undisturbed (reference) conditions of a lake is needed. Phytoplankton contains a range of different pigments, some of which are specific for individual algal groups and can be used as diagnostic markers. Phytoplankton pigments in lake sediments are indicators of prototrophic changes in lakes, since the pigments document changes in algae biomass and the composition of phytoplankton communities. Lake sediments can be dated along with pigment analysis by use of the naturally occurring radioactive isotope²¹⁰Pb.     

Comparison of the interactions ofErwinia carotovora ssp.atroseptica withPhytophthora infestans, Phoma foveata andFusarium coeruleum in rotting potato tubers

Summary An interaction betweenP. infestans andE. carotovora subsp.atroseptica (Eca) in rotting tubers was confirmed and the biochemical basis for its occurrence investigated. The pH of tissue infected withP. foveata became alkaline whereas tissue infected withP. infestans orF. coeruleum did not rise above neutrality, which could promote pathogenicity of Eca by maintaining pH closer to the optimum for polygalacturonase activity. Polygalacturonase, pectate lyase and galactanase were detected in cultures of all three fungi grown on media containing cell wall material or pectin from tubers. AsP. infestans produced more polygalacturonase than the other two fungal tuber rot pathogens the possibility was investigated that oligogalacturonide products of enzymatic degradation of pectin byP. infestans stimulates pathogenicity of Eca. However, while tubers soft-rotted after infiltration with supernatant from fungal cultures grown on tuber cell wall material, controls showed that rotting resulted from infiltration rather than the products contained in the infiltrated water.     

Size grading methods and their relationship to the dimensions,mass and volume characteristics of potato cultivars

Summary The mass, length, breadth and depth were measured for each of 6000 potatoes. Samples of approximately 200 tubers of each of the 10 most commonly grown UK maincrop cultivars from three locations in UK were use. Multivariate log-normal distributions fitted the data well. This result has been used to assess grading methods based on mass, one-dimensional measurements of size, or estimates of riddle size. Prediction of mass using the product of the three principal tuber dimensions shows an error of 10 % or less, against 30 % forthe current riddle method of sizing.

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Zusammenfassung Es wurden die Ziele und die Leistungsf?higkeit von Methoden betrachtet, die zum Kartoffelvermessen angewandt worden sind. Die Tabelle 1 zeigt die Leistung der einfachsten Eindimensional-Messeinrichtung. Es wird ein Bezug hergestelt zum Gewicht und zu optischen Klassierungskriterien. Mit 6000 Knollen wurde eine Untersuchung der Beziehungen zwischen Knollenmass, Gewicht, Volumen und Siebungsgr?sse durchgeführt. Die Knollen stammten aus Proben der zehn wichtigsten UK Sorten, von denen jede in 3 Gebieten des Landes angebaut worden war. Die in den Versuchen verwendete Messeinrichtung wird in Abb. 1 gezeigt. Die Analyse der Ergebnisse (dargestellt in Tab. 2) weist darauf hin, dass sich die Verteilung von Gewicht, L?nge, Breite und Tiefe gut einer mehrdimensionalen log. Normalverteilung n?hert, unabh?ngig von Sorte oder Anbaugebiet. Die aus den Messdaten erhaltenen Werte k?nnen verwendet werden, um Kassifizierungssysteme zu vergleichen, die auf Gewicht und lineare Gr?ssenmessungen basieren. Man kann zum Sch?tzen des Fehlers Pr?diktoren erhalten, wenn zu Gewichtsvoraussage Einzel- oder Mehrfachmasse verwendet werden, die als zuverl?ssigste Kriterien zur Gr?ssenbestimmung gelten. Die Tabelle 3 zeigt die Werte der Pr?diktoren bei der Sch?tzung des Gewichtes. Die Ergebnisse zeigen, dass die Breite ein besserer Pr?diktor für das Gewicht ist als L?nge oder Tiefe, und das Siebungsmass ist jedem Einzelmasskriterium überlegen. Das Siebungsmass ist dem Produkt ausden Massen L?nge Breite und Tiefe unterlegen in Beziehung zum Knollengewicht miteinem Fehler von 30 % gegenüber einem von 10% beim Letzteren. Bei Berücksichtigung des gesch?tzten Gewichtes verringert sich der Fehler auf 9 %, hingegen bei Anrechnung der Sorte und Herkunft auf 8 %. Die Tabelle 4 zeigt die Verteilung der über alle Sorten gemittelten Gewichte für Knollen in den bezeichneten Bereichen des Siebungsmasses für 1983. Die Abbildung 2 ziegt für eine Sorte die Beziehungen zwischen log. Gewicht und log. L?nge und Abbildung 3 die viel engeren Beziehungen zwischen dem log. Gewicht und dem log. Produkt aus L?nge, Breite und Tiefe. Im Hinblick auf den beim Sieben entstehenden viel gr?sseren Fehler erscheint es gleichermassen m?glich, dass optische Klassifizierungssysteme, die die drei wichtigsten Knollenmasse oder eines von diesen benutzen, ebenso erfolgreich sein werden, ohne dass Angaben über Sorte und Herkunft gemacht werden müssen.

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Résumé L'objectif et l'efficaité des méthodes utilisées pour le calibrage des pommes de terre sont examinés. Le tableau 1 montre la performance du plus simple calibreur à unr seule dimension. Les critères pour un calibrage au poids ou optique sont mentionnés. Une étude sur les relations entre les dimensions, le poids le volume et le calibrage a été réalisée sur 6000 tubercules des dix principales variétés de pommes de terre cultivées en Grande Bretagne, chancune issue de trois localités. Les matérielde mesure utilisé est présenté (figure 1). L'analyse des résultats (tableau2) montre que la distribution du poids, de la longueur, de la largeur et de la hauteur des tubercules se rapproche assez bien d'une distribution log-normale à variables multiples, indépendamment du lieu et de la variété. Les valeurs issues de ces résultats peuvent être utilisées pur comparer les systèmes de calibrage basés sur le poids ou les mesures linéaires de calibrage. Des veriables prédicatives peuvent être données pour estimer l'erreur de poids à partir d'une ou plusieurs dimensions en considérant les critères de calibrage les plus fiables. Le tableau 3 regroupe les variables pour l'estimation du poids. Les résultats montrent que la largeur est un meilleur indicatuer de poids que la longuer ou la hauteur et le calibrage est supérieur à tout critère dimensionnel pris séparément. Le calibrage est inférieur au produit des dimensions longueur, largeur et hauteur pour la détermination du poids avec une erreur de 30% au lieu de 10 %, dans le deuxième cas. Sila variété est prise en comple, l'erreur n'est plus que de 9 % et elle est réduite à 8 % en considérant la variété et le lieu. Le tableau 4 montre la distribution des poids moyens de toutes les variétés pour fiddérents calibres en 1983. La figure 2 présente pour une variété le poids-log centre la longuers-log et la figure 3 indique que la relation entre le poids-log et le produit-log de la longuer, largeur et hauteur est nettement plus proche. Etant donné l'erreur plus grande par le calibrage, il semble que les systèmes optiques, à partir des trois dimensions principales du tubercule ou d'une certaine mesure de cellesci puissent être utilisées avec succès sans tenir compte de la variété ou de l'origine.

     

AgEcon Search: History and Future of a Collaborative Subject Repository

ABSTRACT

AgEcon Search is a free-to-user subject repository containing the full text of the grey literature and small press journals of agricultural and applied economics. It has developed over the last 14 years, through a close relationship between librarians and economists. Growth in international documents is in the future plan for AgEcon Search, and the developers hope it will serve as a prototype for subject repositories in other disciplines.     

Standard area diagram set for assessment of severity and temporal progress of apple blotch

Apple blotch (Marssonina coronaria) is a foliar disease of increasing importance globally. Methods to quantify the disease and knowledge about epidemiology are required for new studies on the disease. The objectives of this study were to develop a standard area diagram set (SADs) to assess apple blotch severity and to describe the temporal progress of the disease under field conditions on older and younger leaves of two apple cultivars. For the development of SADs, symptomatic leaves were collected and scanned to obtain the actual severity. Based on the pattern of the disease, a SADs was elaborated and validated. Leaf severities were estimated without and with SADs by 12 raters to validate the tool. After validation, the SADs was used to assess apple blotch in older and younger leaves of selected shoots during the vegetative cycle of cvs. Eva and Gala. SADs severities ranged from 0.2 to 96%. Accuracy, precision, and reliability of the estimates were significantly improved when the SADs was used. In the field, the onset of apple blotch was in late spring and greater increases in severity occurred during summer. Rates of disease progress ranged from 0.09 to 0.13. Epidemics were different in older and younger leaves at the end of the apple vegetative cycle for both cultivars tested. Our work provided a tool for apple blotch quantification and described the disease progress curve under subtropical conditions, which can contribute as basis for future studies.

     

Postoperative management of the large colon volvulus patient.

Horses with large colon volvulus (LCV) often require intensive postoperative medical management. Although early referral and surgical intervention are critical for minimal postoperative complications and a successful outcome, this is often not possible for many reasons. Endotoxemia, extensive mucosal damage with subsequent severe hypoproteinemia, and focal ischemic necrosis are the major causes of postoperative morbidity and mortality.Although fluid therapy, flunixin meglumine, and antimicrobials are still the mainstay of perioperative management, synthetic colloids are being used to maintain plasma oncotic pressure, hyperimmune antiendotoxic plasma and polymixin B are being used for management of endotoxemia, and lidocaine and constant rate infusion of butorphanol can be used for postoperative analgesia. The use of heparin, dimethyl sulfoxide, and corticosteroids for management of LCV are still controversial. Future studies are required to investigate nutritional improvement and methods to manage cases after surgery to prevent recurrence.