Removal of fungus and prevention of fungal reinfestation in stored dry salted fish

A simple and effective method is described for converting dry fish products infested with fungus and red halophilic bacteria to acceptable ones. Washing, drying and then smearing with a mixture of 3% sodium propionate in dry, refined salt in a ratio of 1 part mixture: 10 parts dry fish resulted in the fish having a shelf life of 5 months.

Elimination of dengue by community programs using Mesocyclops(Copepoda) against Aedes aegypti in central Vietnam

From September 2000 to June 2003, a community-based program for dengue control using local predacious copepods of the genus Mesocyclops was conducted in three rural communes in the central Vietnam provinces of Quang Nam, Quang Ngai, and Khanh Hoa. Post-project, three subsequent entomologic surveys were conducted until March 2004. The number of households and residents in the communes were 5,913 and 27,167, respectively, and dengue notification rates for these communes from 1996 were as high as 2,418.5 per 100,000 persons. Following knowledge, attitude, and practice evaluations, surveys of water storage containers indicated that Mesocyclops spp. already occurred in 3-17% and that large tanks up to 2,000 liters, 130-300-liter jars, wells, and some 220-liter metal drums were the most productive habitats for Aedes aegypti. With technical support, the programs were driven by communal management committees, health collaborators, schoolteachers, and pupils. From quantitative estimates of the standing crop of third and fourth instars from 100 households, Ae. aegypti were reduced by approximately 90% by year 1, 92.3-98.6% by year 2, and Ae. aegypti immature forms had been eliminated from two of three communes by June 2003. Similarly, from resting adult collections from 100 households, densities were reduced to 0-1 per commune. By March 2004, two communes with no larvae had small numbers but the third was negative; one adult was collected in each of two communes while one became negative. Absolute estimates of third and fourth instars at the three intervention communes and one left untreated had significant correlations (P = 0.009-< 0.001) with numbers of adults aspirated from inside houses on each of 15 survey periods. By year 1, the incidence of dengue disease in the treated communes was reduced by 76.7% compared with non-intervention communes within the same districts, and no dengue was evident in 2002 and 2003, compared with 112.8 and 14.4 cases per 100,000 at district level. Since we had similar success in northern Vietnam from 1998 to 2000, this study demonstrates that this control model is broadly acceptable and achievable at community level but vigilance is required post-project to prevent reinfestation.

Evaluation of SP1001 (Pelargonic Acid) in Combination with Glyphosate on Cattail and Alligatorweed

Cattail (Typha latifolia L.) is a common and troublesome weed in shallow, freshwater environments throughout the United States. Alligatorweed (Alternanthera philoxeroides (Mart.)Griseb.), in spite of the introduction and success of several insects as biological controls, remains a troublesome we4ed in a a number of locations in the Southeast where there are frequent human disturbances (e.g., insecticide spraying, mechaniceal removal, etc.) and/or weather conditions that affect the life cycle of the insects (Kay1992, Vogt et al. 1992). Both of these weeds routinely are managed by foliar applications of the herbicide, glyphosate [N-(phosphonomethyl)glycine]. Regrowth and reinfestation of previously treated areas usually necessitates additional herbicide application during subsequent years. A new product that could enhance the activity of glyphosate on these weeds would be useful in their management. In 1997, SePRO Corp. initiated t4esting of an experimental compound, SP1001, to determine its efficacy either as a herbicide or as an adjuvant to boost the activity of glyphosate for use in aquatic sites. The objective of this study was to evaluate the potential for using SP1001 as an adjuvant to replace surfactants customarily used during application of glyphosate for control of cattail and alligatorweed.

Épocas de manejo químico de Brachiaria decumbens antecedendo o plantio direto de soja

O manejo químico da cobertura vegetal e a manutenção da palhada sobre o solo são preocupações comuns para os produtores que adotam o sistema plantio direto na região dos cerrados. Com o objetivo de estudar a influência da época de manejo químico de B. decumbens sobre o desenvolvimento e a produtividade da cultura da soja em sistema plantio direto, foram realizados dois ensaios a campo, respectivamente, com os cultivares BRS 154 e MG/BR 46-Conquista, no ano de 2003. em cada ensaio, testaram-se quatro épocas de manejo de B. decumbens antecedendo a semeadura da soja (28, 14, 7 e 0 dias), utilizando-se o herbicida glifosato. Os ensaios foram conduzidos em delineamento inteiramente casualizado, utilizando-se três repetições no primeiro e quatro no segundo. Determinou-se a matéria seca da cobertura vegetal e avaliou-se a reinfestação de B. decumbens. Na cultura da soja, foram determinados: altura de inserção da primeira vagem, número de vagens por planta, umidade dos grãos, massa de 100 grãos e produtividade. Com base nos resultados obtidos, conclui-se que a época mais adequada para o manejo químico de B. decumbens com glifosato situa-se entre 7 e 14 dias antes da semeadura da cultura da soja e que a escolha da época de manejo químico da cobertura vegetal afeta de forma decisiva o desenvolvimento e a produtividade da cultura.

Formação de palhada por braquiárias para adoção do sistema plantio direto

Com o objetivo de avaliar espécies forrageiras para formação de palhada para adoção do sistema plantio direto, foi pesquisado o potencial de Brachiaria decumbens e B. brizantha, comparadas ao milheto (Pennisetum glaucum). As plantas de cobertura foram semeadas em março e conduzidas até novembro (momento do manejo químico). Aos 50, 110 e 250 dias após a semeadura (DAS) foram avaliadas a composição específica das infestantes na cobertura vegetal, a porcentagem visual de cobertura do solo e o acúmulo de massa vegetal seca das coberturas. As braquiárias foram eficientes na formação de palha (acima de 11 tha-1), sendo promissoras para o sistema plantio direto. Também, observou-se densa cobertura do solo, com supressão do desenvolvimento de plantas daninhas, o que não se percebeu com milheto, cujo maior potencial de cobertura do solo e acúmulo (10,5 t ha-1) de massa ocorreu no fim do seu ciclo (110 DAS) e, 3,2 t ha-1 de massa vegetal seca aos 250 DAS. Devido à rápida decomposição da palha de milheto observou-se, também, reinfestação da área por plantas daninhas.

Eficácia de glyphosate em plantas de cobertura

Objetivou-se comparar a eficácia de três dosagens do herbicida glyphosate para a dessecação de Brachiaria decumbens, B. brizantha cv. Marandu e vegetação espontânea, visando a adoção do sistema plantio direto. Utilizou-se delineamento experimental de blocos ao acaso, num esquema fatorial 3 x 3, com quatro repetições. Testaram-se três tipos de cobertura vegetal e três dosagens de glyphosate (1,44, 2,16 e 2,88 kg ha-1). Aos 7, 14, 21 e 28 dias após a aplicação (DAA), foram feitas avaliações visuais da porcentagem de controle das coberturas vegetais e, aos 45 DAA, avaliações visuais da porcentagem de reinfestação da área. Conclui-se que, para as espécies que compunham a vegetação espontânea, o uso de 1,44 kg ha-1 proporcionou bom controle, sem no entanto evitar rebrotes de Digitaria insularis. Para as braquiárias, a mesma taxa de controle foi observada a partir de 2,16 kg ha-1. A camada de palha das braquiárias sobre o solo não foi capaz de suprimir a emergência de Cyperus rotundus, Alternanthera tenella, Raphanus raphanistrum, Bidens pilosa e Euphorbia heterophylla.

Inflammatory reaction to the human bot-fly, Dermatobia hominis, in infested and reinfested mice

Two groups of mice were infested with first stage larvae of the human bot-fly, Dermatobia hominis (Linnaeus Jr) (Diptera: Oestridae). In the first group, skin biopsies were carried out 1, 3, 5, 7, 10 and 18 days after infestation. The second group was also infested but had all the larvae removed 5 days after infestation. The mice in the latter group were reinfested 4 weeks later and skin biopsies were carried out 1, 3, 5, 7, 10 and 18 days after reinfestation. In the first group, an inflammatory reaction began slowly, the neutrophils being the main inflammatory cells, eosinophils being scarce. The reaction progressed with time, developing a necrotic halo around the larvae containing inflammatory cells surrounded by fibroblasts. The inflammation invaded the adjacent tissue. In the second group, the inflammatory reaction was intense on the day immediately after reinfestation, the pattern being changed by the presence of a large number of eosinophils. Activated fibroblasts surrounding the necrotic area around the larvae appeared 3 days after reinfestation in the second group and 7 days after infestation in the first group. The results demonstrated that the previous contact with the antigens elicited the early arrival of eosinophils, probably through the chemotactic factors liberated by mast cells in the anaphylactic reaction.

Ultrastructure features of the midgut of the female adult Amblyomma cajennense ticks Fabricius, 1787 (Acari: Ixodidae) in several feeding stages and subjected to three infestations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Histopathology and Ultrastructure Features of the Midgut of Adult Females of the Tick Amblyomma cajennense Fabricius, 1787 (Acari: Ixodidae) in Various Feeding Stages and Submitted to Three Infestations

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Variabilidade genética e variação das regiões heterocromáticas em linhagens de Triatoma infestans (Heteroptera : Reduviidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Interação entre Sorgo Sacarino e plantas daninhas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Scabies outbreak in an intensive care unit with 1,659 exposed individuals--key factors for controlling the outbreak

OBJECTIVE: To investigate a large outbreak of scabies in an intensive care unit of a university hospital and an affiliated rehabilitation center, and to establish effective control measures to prevent further transmission. DESIGN: Outbreak investigation. SETTING: The intensive care unit of a 750-bed university hospital and an affiliated 92-bed rehabilitation center. METHODS: All exposed individuals were screened by a senior staff dermatologist. Scabies was diagnosed on the basis of (1) identification of mites by skin scraping, (2) identification of mites by dermoscopy, or (3) clinical examination of patients without history of prior treatment for typical burrows. During a follow-up period of 6 months, the attack rate was calculated as the number of symptomatic individuals divided by the total number of exposed individuals. INTERVENTIONS: All exposed healthcare workers (HCWs) and their household members underwent preemptive treatment. Initially, the most effective registered drug in Switzerland (ie, topical lindane) was prescribed, but this prescription was switched to topical permethrin or systemic ivermectin as a result of the progression of the outbreak. Individuals with any signs or symptoms of scabies underwent dermatological examination. RESULTS: Within 7 months, 19 cases of scabies were diagnosed, 6 in children with a mean age of 3.1 years after exposure to the index patient with HIV and crusted scabies. A total of 1,640 exposed individuals underwent preemptive treatment. The highest attack rate of 26%-32% was observed among HCWs involved in the care of the index patient. A too-restricted definition of individuals at risk, noncompliance with treatment, and the limited effectiveness of lindane likely led to treatment failure, relapse, and reinfestation within families. CONCLUSIONS: Crusted scabies resulted in high attack rates among HCWs and household contacts. Timely institution of hygienic precautions with close monitoring and widespread, simultaneous scabicide treatment of all exposed individuals are essential for control of an outbreak.

Use of sulfuryl fluoride in the management of strongly phosphine-resistant insect pest populations in bulk grain storages in Australia

Sulfuryl fluoride (SF), an effective structural fumigant, is registered recently as Profume™ for controlling insect pests of stored grains and processed commodities. Information on its effectiveness in disinfestation of bulk grain, however, is limited. The ongoing problem with the strong level of resistance to phosphine has been addressed recently through deployment of SF as a ‘resistance breaker’ in bulk storages in Australia. This paper discusses important results on the efficacy of SF against key phosphine- resistant insect pests, lesser grain borer, Rhyzopertha dominca, red flour beetle, Tribolium castaneum, rice weevil, Sitophilus oryzae and the rusty grain beetle, Cryptolestes ferrugineus. We have established CT (g-hm3) profiles for SF against these insect pests at two temperature regimes 25 and 30°C, that showed that both temperature and exposure period (t) has significant influence on the effectiveness of SF than the concentration. Over a seven days fumigation period, CTs of 800 and 400 g-hm3 achieved complete control of all the target pests, including the most strongly phosphine - resistant species, C. ferrugineus at 25 and 30°C, respectively. Results from four industry scale field trials involving currently registered rate of SF (1500 g-hm3) over 2–14 d exposure period, confirmed its effectiveness in achieving complete control of the target pest species. The assessment of postfumigation grain samples across all the test storages indicated that the reinfestation occurs after three months. Monitoring resistance to phosphine in C. ferrugineus over a six year period (2009–2015), showed a significant reduction in resistant populations after the introduction of SF into the fumigation strategy at problematic storage sites. Overall our research concludes that SF is a good candidate to be used as a ‘resistance breaker’ where phosphine resistance is prevalent.