Effects of loosing Aigamo ducks on the growth of rice plants, weeds, and the number of arthropods in paddy fields

Aigamo duck farming has been noticed as one of the techniques of environmental conservation agriculture. This study was carried out to investigate the effects of loosing Aigamo ducks on the growth and production of rice plants, the quantity of weeds and arthropods, and the balance of nitrogen (N) in paddy fields by changing the density of the Aigamo ducks. A paddy field was divided into three test plots: a 10-Aigamo-duck plot, a five-Aigamo-duck plot, and a weeding plot. The results show that the height, number of culms, and yield crops of the rice plants increased more in the 10-Aigamo-duck plot and the five-Aigamo-duck plot than that of the weeding plot. Millet ( Echinochloa oryzicola ) remained in both the Aigamo duck plots. The weeding plot was covered with monochoria ( Monochoria vaginalis ). In both the Aigamo duck plots, the outbreak of total arthropods was lower than that of the weeding plot, but the number of rice plants damaged by grass leaf rollers ( Cnaphalocrocis medinalis ) was increased. The number of spiders, regarded as useful insects, did not differ that much between the experimental plots. The N content of the soil did not differ as an effect of loosing the Aigamo ducks. The rice plants in the 10-Aigamo-duck plot absorbed more N than the rice plants in the other plots.     

Cutaneous reactivity to mosquito bites and its antigens in cats

Abstract This study describes 26 cats with mosquito bite hypersensitivity. Most were short-haired, free-roaming cats. Typical clinical features were seasonal (summer), symmetric miliary dermatitis on the pinnae. Mosquito bite exposure with Aedes albopictus was performed on the pinnae and the lateral thorax in five cases and three healthy cats. All sites showed weals within 20 min. Papules, which revealed eosinophilic dermatitis, were recognized during a 12–48-h period. The control cats showed only slight and transient erythema after being bitten. Intradermal skin tests with an extract of A. albopictus were performed in three cases, and Prausnitz-Küstner tests under A. albopictus bites were performed in three cases. Both tests showed weals in all cases studied, although papules were not observed. Intradermal skin tests with the control cats, and Prausnitz-Küstner tests with saline and healthy cat serum failed to produce any positive reactions. The findings indicate that mosquito bite hypersensitivity in cats is triggered by a type I hypersensitivity reaction to mosquito antigens. Certain other factors may be involved in the formation of delayed papular reactions. Whether this is a normal or abnormal reaction to mosquito bites is also discussed. Résumé— Cette étude a été réalisée sur 26 chats atteints d'hypersensibilité aux piqûres de moustiques. La plupart des chats sont des chats à poils courts vivant à l'extérieur. Les lésions cliniques sont caractérisées par une dermatite miliaire symétrique sur les pavilions auriculaires survenant l'été. Une exposition aux piqûres de moustique (Aedes albopictus) a été réalisée sur les pavilions auriculaires et sur la face latérale du thorax de 5 chats atteints et de 3 chats sains. Tous les sites d'exposition montrent des reactions à 20 minutes. Ces papules qui traduisent une dermite éosinophilique, persistent pendant 12 à 48 heures. Les chats sains ne montrent qu'un érythème transitoire après la piqûre, des tests d'intradermoréaction avec un extrait d'A. albopictus ont été réalisés dans 3 cas, des tests de Prausnitz-Küstner spécifiques dans 3 cas. Les deux tests montrent des reactions dans tous les cas étudiés bien que des papules ne soient pas observées. Ces tests réalisés sur les chats témoins, ne montrent aucune reaction, positive ou significative. Ces résultats suggèrent que l'hypersensibilité aux piqûres de moustiques chez le chat est regie par une hypersensibilité de type I à divers antigènes de moustique. D'autres facteurs doivent intervenir dans la formation des reactions papuleuses retardées. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Réactivité cutanée aux piqûres de moustiques et à leurs antigènes chez le chat.) Veterinary Dermatology 1997; 8 : 19–26.] Résumén Este estudio describe 26 gatos con hipersensibilidad a la picadura de mosquito. La mayoria eran gatos en régimen abierto de pelo corto. Las caracteristicas clinicas tipicas fueron dermatitis miliar simétrica estacional (verano) en pabellones auriculares. Se llevó a cabo una exposición a la picadura del mosquito Aedes albopictus en los pabellones y en el tórax lateral en 5 casos y 3 gatos sanos. Todas las zonas mostraron ronchas a los 20 minutos. Aparecieron pápulas con dermatitis eosinofilica a las 12 a 48 horas. Los gatos control mostraron solamente eritema leve y transitorio tras la picadura. Se realizaron pruebas cutáneas intradérmicas con extracto de A. albopictus en 3 casos y pruebas de Prausnitz-Küstner bajo picaduras de A. albopictus en 3 casos. Ambas pruebas mostraron ronchas en todos los casos estudíados, aunque no se observaron pápulas. Las pruebas intracutáneas con los gatos control y las pruebas de Prausnitz-Küstner con suero salino y suero de gatos sanos no causaron reacción positiva. Estos hallazgos indican que la hipersensibilidad a la picadura de mosquito se inicia por una hipersensibilidad de tipo I a antigenos del mosquito. Otros factores pueden estar implicados en la formación de reacciones papulares retardadas. Se discute si esta es una reacción normal o anormal a la picadura de mosquito. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Reactividad cutanea a las picaduras de mosquito y sus antigenos en el gato.) Veterinary Dermatology 1997; 8 : 19–26.] Zusammenfassung— Diese Studie beschreibt 26 Katzen mit Mückenstichhypersensibilität. Die meisten der Tiere waren kurzhaarig und hatten Freilauf. Die typischen klinischen Bilder bestanden in säsonaler (Sommer), symmetrischer miliarer Dermatitis an den Ohrmuschein. Es wurde eine Exposition auf Mückenstiche mit Aedes albopictus an den Ohrmischein und am lateralen Thorax bei 5 Patienten und 3 gesunden Katzen durchgeführt. Alle Stellen zeigten Quaddeln innerhalb von 20 Minuten. Papeln, die eine eosinophile Dermatitis enthüllten, wurden nach einer Zeitspanne von 12 bis 48 Stunden gesehen. Die Kontrollkatzen zeigten ein nur leichtes und transientes Erythem nach dem Biß. Intradermale Hauttests mit einem Extrakt von A. albopictus wurden in 3 Fallen durchgeführt und Prausnitz-Küstner-Tests unter A. albopictus-Bissen wurden in 3 Fallen durchgeführt. Beide Tests zeigten Quaddeln in alien untersuchten Fallen, obwohl Papeln nicht beobachtet wurden. In den intradermalen Hauttests bei den Kontrollkatzen und Prausnitz-Küstner-Tests mit Kochsalz-Lösung und Serum gesunder Katzen gelang es nicht, irgendweiche positiven Reaktionen zu erzeugen. Diese Befunde zeigen, daß Mückenstichhypersensibilität bei Katzen durch eine Typ 1-Hypersensibilitätsreaktion auf Mückenantigene ausgelöst wird. Bestimmte andere Faktoren können in die Bildung von verzögerten papulären Reaktionen miteinbezogen sein. Ob dies eine normale oder unnormale Reaktion auf Mückenstiche ist, wird ebenfalls diskutiert. [Mashiko N, Takuo I. Cutaneous reactivity to mosquito bites and its antigens in cats. (Hautreaktivität auf Mückenstiche und Antigene bei der Katze.) Veterinary Dermatology 1997; 8 : 19–26.]     

Experimental induction of secretory and purulent otitis media by the surgical obstruction of the eustachian tube in dogs

Secretory and purulent otitis media developed after the surgical obstruction of the eustachian tube in dogs. On 3 days after the obstruction, secretory otitis media alone was induced without regard of presence of aerobes in middle ear fluid. On 10 and 15–20 days, two types of otitis media were induced; in the secretory type aerobes were hardly detected, and in the purulent type a considerable number of various species of aerobes were detected. The present results suggest that the eustachian tube obstruction readily generates secretory otitis media and, when aerobes are present in the middle ear, the otitic condition may develop to purulent otitis media.     

Pigmented Plaques Associated with Papillomavirus Infection in Dogs: Is this Epidermodysplasia Verruciformis?

Abstract— Two Pugs and two Miniature Schnauzers with multiple pigmented epidermal nevi were investigated. The four dogs had pigmented cutaneous maculae and plaques. Histopathological evaluation showed papillated or digitated epidermal hyperplasia with hypermelanosis and giant keratohyalin granules in the stratum granulosum. Immunohistochemical staining revealed papillomavirus group-specific antigen in the skin specimens from all four dogs. Electron microscopic study of the specimens from two dogs revealed numerous round viral particles within the nuclei of the keratinocytes in the upper stratum granulosum. It was suspected that papillomavirus was the etiologic agent of the lesions, and that Pugs and Miniature Schnauzers might be predisposed to infection. These findings indicate this canine dermatosis resembles epidermodysplasia verruciformis (EV) of humans, a rare chronic disease caused by human papillomavirus. The potential for transformation of the lesions to squamous cell carcinoma is also suspected and discussed. Résumé— Deux Carlins et deux Schnauzers nains présentant de multiples naevi épidermiques pigmentés sont examinés. Les quatre chiens présentent des macules et des plaques pigmentées. Les lésions histopathologiques montrent une hyperplasie épidermique papillaire ou digitée avec une hypermélanose et la présence de grains de kératohyaline dans le stratum corneum. Les colorations immunohistochimiques révèlent des antigènes spécifiques du groupe des papillomas virus dans les biopsies des quatre chiens. L'étude ultrastructurale à partir des biopsies de deux chiens montrent de nombreuses particules virales rondes dans les noyaux des kératinocytes des couches supérieures du stratum granulosum. II a été suspecté que le papilloma virus était l'agent causal des lésions et que les Carlins et les Schnauzers nains pouvaient être prédisposés à cette infection. Ces éléments font que cette dermatose observée chez le chien ressemble à l'épidermodysplasie verruciforme de l'homme, une dermatose chronique rare causée par un papilloma virus humain. La potentialité de transformation des lésions en épithélioma spinocellulaire est aussi suspectée et discutée. [Nagata, M., Nanko, H., Moriyama, A., Washizu, T., Ishida, T. Pigmented plaques associated with papilloma virus infection in dogs: Is this epidermodysplasia verruciformis? (Plaques hyperpigmentées associées à une infection à papilloma virus chez le chien: est-ce épidermodysplasie verruciforme?). Resumen— Se investigó dos perros de raza Pug y dos de raza Schnauzer Miniatura con múltiples nevos epidérmicos pigmentados. Los cuatro perros presentaban máculas y placas cutáneas pigmentadas. El estudio histológico mostró hiperplasia epitelial con papilas y digitaciones, así como hipermelanosis y gránules de queratohialina gigantes en el estrato granuloso. Las tinciones immunohistoquimicas detectaron antígeno grupo-específico de papilomavirus en las muestras de los cuatro animales. Mediante estudios de microscopía electrónica en muestras de dos de los perros se observaron numerosas particulas virales redondas en el núcleo de los queratinocitos más superficiales del estrato granuloso. Se sospechó que Papilomavirus era el agente etiológico de estas lesiones y que los Pugs y los Schnauzer Miniatura podrian estar predispuestos a la infección. Estos hallazgos indican que esta dermatosis canina es parecida a la Epidermodisplasia Verruciforme (EV) de la especie humana, una enfermedad crónica rara causada por el Papilomavirus Humano. Se sospecha y discute la posible transformación de estas lesiones a carcinoma de células planas. [Nagata, M., Nanko, H., Moriyama, A., Washizu, T., Ishida, T. Pigmented plaques associated with papilloma virus infection in dogs: Is this epidermodysplasia verruciformis? (Placas pigmentadas asociadas con infección por papillomavirus en el perro: se trata de epidermodisplasia verruciforme?)     

Age‐dependent distribution of juvenile southern bluefin tuna (Thunnus maccoyii) on the continental shelf off southwest Australia determined by acoustic monitoring

Juvenile southern bluefin tuna (Thunnus maccoyii, SBT) were monitored in nearshore waters off southwest Australia using acoustic tagging and monitoring over five austral summers (2002/2003–2006/2007) to determine patterns in age‐based distribution of SBT. A total of 20–70 receivers were deployed in early December along one to three cross‐shelf transects and at three inshore topographic features (lumps) where SBT are known to occur; and a total of 59–84 juvenile SBT (41–90 cm fork length) were tagged and released each year. After several months, receivers were recovered, and data extracted. In 2002/2003 and 2003/2004, 2‐yr‐old SBT were detected more frequently in nearshore areas than did 1‐yr old fish. Similarly in 2004/2005 and 2006/2007, it was the larger 1‐yr‐old SBT that were detected more frequently at inshore lumps (>85% of detections) while small 1‐yr‐old SBT were detected more widely over the study area. In 2005/2006, although large 1‐yr‐old SBT were still detected more frequently at inshore lumps than small 1‐yr old SBT, the percentage of all detections at lumps was lower at 31.5%, indicating wider distribution of both small and large age‐1 fish. The observed age‐dependent distribution pattern may be enhanced by the distribution of prey, which disperse or concentrate depending on the local oceanography.     

Detection of <Emphasis Type="Italic">Pythium aphanidermatum </Emphasis>in Sludge from Drinking-water Plant

Pythium aphanidermatum causing damping off of cucumber seedlings was detected in water clarifier sludge from a drinking-water plant in the Kanto district. During December 1996 to November 1997, the pathogen was consistently isolated from the sludge at <1.9 CFU ml^-1 of the sludge. Received 25 February 2000/ Accepted in revised form 28 April 2000     

The aerobic bacterial flora of the middle and external ears in normal dogs

The aerobic bacterial flora of the middle and external ears was elucidated in 30 normal dogs (60 ears). Bacterial swab samples were obtained by rubbing the surface of the tympanic cavity and external ear canal. In the middle ear, bacteria were cultured from 48 per cent of the total ears and mainly included Escherichia coli (8 per cent), yeasts (8 per cent), staphylococci (7 per cent) and branhamella (7 per cent). In the external ear, bacteria were found in 46 per cent of the total ears and staphylococci (19 per cent) and yeasts (7 per cent) were the main isolates. Mycoplasma was found in one external ear sample, but in no middle ear samples in an examination of 20 ears. The same type of bacterium was hardly ever found in both the middle and external parts of each ear.     

Pharmacological treatments against Ichthyobodo necator (Henneguy, 1883) in rainbow trout, Oncorhynchus mykiss (Walbaum)

Abstract. Various antiparasitic drugs belonging to several pharmacological groups were tested by bath administration for in vivo activity against a natural infestation of rainbow trout. Oncorhynchus mykiss (Walbaum), by he flagellate protozoan Ichthyobodo necator. Fish were also monitored for signs of drug toxicity. Complete elimination of infestation in all fish was achieved only by bithionol (25 mgl^-1 for 3h on two consecutive days). Ketoconazole, toltrazuril, amprolium, sulphaquinoxaline, quinacrine, N-metylglucamine, chloroquine, 1,3-di-6-quinolylurea, diminazene aceturate and paromomycin were not effective. Diminazene aceturate (100 mgl^-1, 3h) was the only drug which was clearly toxic. The comparison of the response of symptomatic and asymptomatic infested fish to a formaldehyde bath indicates that poor health caused by I. necator may greatly increase the susceptibility of fish to the toxic effects of a drug or chemical.