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Studies under constant temperatures are the most common to estimate the Postmortem Interval (PMI). It is imperative that forensic sciences have data from studies carried out in the field. Therefore, this work aims to: (1) evaluate the parameters (weight, length, development time) associated with the life cycles of Lucilia ochricornis (Wiedemann) (Diptera: Calliphoridae) and Lucilia purpurascens (Walker) under experimental conditions in the field considering fluctuating temperatures, and (2) compare these results with those known and published by the same authors for cultures realized in the laboratory under constant temperatures; which will permit us to contrast the most widely used existing methodologies for forensic application in estimating the minimum postmortem interval (PMImin). For each season of the year, cultures of both species were made in the field, collecting information on temperature, humidity, and photoperiod to perform laboratory cultures, later comparing: development time, length, weight, and Accumulated Degree-Hours (ADH) in both types of cultures. Methods for estimating the PMI were obtained and validated with the information of the cultures grown in the field. The two types of cultures showed differences between each other for both species. The forensic use methods to estimate PMI were enhanced and their precision increased when maximum larval length data were used, and it was also concluded that feeding larval stages are the most accurate to be used in making estimates because the larva is growing. The estimation of the PMI through the use of necrophagous flies development remains reliable for obtaining the PMImin.

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Predation is a major process in determining the composition and dynamics of necrophagous dipteran assemblages and has implications for the colonization of cadavers. This work describes behavioural interactions between necrophagous larvae under a predator-prey perspective, using as a model the predatory species Chrysomya albiceps (Wiedemann) (Diptera: Calliphoridae) and three species of prey: Lucilia eximia (Wiedemann) (Calliphoridae), Synthesiomyia nudiseta (Wulp) (Muscidae) and Peckia (Peckia) chrysostoma (Wiedemann) (Sarcophagidae). Using experimental arenas, we observed behavioural acts, such as escape, avoidance and prey discrimination in three experiments, which also incorporated predator density. We demonstrate that the number of escapes, avoidance and predation varies according to the type of prey. Lucilia eximia and P. chrysostoma are able to avoid and/or escape the predator more frequently when compared to S. nudiseta. At least 70% of larvae of both species successfully evaded from C. albiceps attack. Low frequency of escape, associated with strong ability to counterattack, was observed for S. nudiseta. Peckia chrysostoma and L. eximia were the preferred items in the experiment of prey discrimination in both 2- and 3-choice tests. Predation occurs quickly, and the minimum predation time varied according to the prey species and predator density. Remarkably, prey handling varied with the species: whilst individual larvae chased and killed L. eximia, 75% of predation of P. chrysostoma occurred in groups of two or more C. albiceps larvae. Differential intraguild predation has implications for reducing populations of carrion insects-consequently affecting the likelihood of sampling necrophagous larvae in human cadavers.

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Fournier's Gangrene is a fulminating necrotizing fasciitis of the perineum and genitalia. Standard treatment involves immediate excision of all necrotic tissue, aggressive antibiotic coverage, and supportive medical care. Still, the infection is commonly fatal or disfiguring. Wound treatment with disinfected blowfly larvae (maggot debridement therapy or MDT) has been shown to be highly effective, with multiple studies demonstrating effective debridement, disinfection, and promotion of granulation tissue. MDT also has been associated with preservation of viable tissue and minimised blood loss. This report describes a prospective clinical study of MDT for Fournier's gangrene aimed to test the hypothesis that early use of maggots could decrease the number of surgical treatments required to treat Fournier's gangrene. Subjects were provided with one initial surgical excision, followed by debridement using only medical grade Lucilia sericata larvae. Only two subjects were enrolled, both diabetic men. Intensive care and culture-directed antimicrobial coverage were administered as usual. Maggot debridement was associated with the disappearance of necrotic tissue, control of infection and granulation tissue growth. In both subjects, wounds healed without requiring further surgical resection or anatomical reconstruction. Maggot therapy decreased the number of surgical procedures that otherwise would have been necessary, and led to favourable outcomes.

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One of the most important contributions of forensic entomology is to assist criminal expertise to determine the postmortem interval, which depends on the duration of the immature stages of insects of forensic interest. On the other hand, the time of development of the different stages varies according to the species; therefore, its identification is essential. Currently, few studies have investigated the use of cuticular hydrocarbons, and none regarding fatty acids, as complementary taxonomic tools to expedite species identification. Therefore, we evaluated whether cuticular hydrocarbons together with fatty acids of eggs of flies of the family Calliphoridae, main group of forensic interest, can be used to distinguish species. The analyses were performed by chromatographic techniques. The results show that there are significant differences between the composition of cuticular hydrocarbons and fatty acids between species and, therefore, they can be used to provide a complementary taxonomic tool to expedite the forensic expertise.

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RESUMEN Introducción: L. eximia es una especie de amplia distribución geográfica en Costa Rica, cuyas poblaciones son estables durante todo el año. Las características biológicas de ésta permiten concebirla como un potencial indicador forense para el cálculo del intervalo post mortem mínimo (IPM). Objetivo: Comparar el IPM calculado mediante un modelo de acumulación térmica con L. eximia (Diptera: Calliphoridae), con el IPM real en cadáveres de cerdos domésticos (Sus scrofa). Material y Métodos: Dos cadáveres de cerdo fueron expuestos en un bosque premontano húmedo tropical. A partir de dichos cadáveres se colectaron larvas de L. eximia a las 78, 144 y 192 horas posteriores al momento de muerte y se propició su desarrollo en condiciones controladas. Con los datos generados, se realizaron retroproyecciones térmicas para efectuar el cálculo del IPM. Resultados: L. eximia requirió en total 7 236,50 grados- hora acumulados (ADH) para culminar su desarrollo. Los IPM calculados mediante el modelo de acumulación térmica para los tres momentos de colecta fueron 112,56; 153,60 y 104,64 horas. Únicamente el valor intermedio no presentó diferencias estadísticamente significativas con el tiempo de muerte conocido (p>0.05). Conclusiones: El modelo de acumulación térmica en que se utilizó L. eximia brindó información precisa sobre el IPM sólo cuando se tomaron las muestras en el campo a las 144 horas, lo que perfila su utilidad para las primeras etapas de la descomposición cadavérica.

ABSTRACT Introduction: L. eximia is a species that shows a wide geographical distribution in Costa Rica, whose populations are stable throughout the year. The biological characteristics of L. eximia allow it to be considered as a potential forensic indicator for the calculation of the minimum post mortem interval (PMI). Objective: To compare the PMI calculated by a thermal accumulation model with L. eximia (Diptera: Calliphoridae), with the PMI in corpses of pigs (Sus scrofa). Methods: Two pig corpses were exposed in a tropical premontane moist forest. Larvae of L. eximia were collected from the pig carcasses at 78, 144 and 192 hours after the moment of death, and their development was promoted under controlled conditions. With the data generated, thermal back-projections were made to calculate the PMI. Results: L. eximia required a total of 7 236.50 accumulated degree hours (ADH) to complete its life cycle. The IPMs calculated by the thermal accumulation model were 112.56, 153.60, and 104.64 hours, respectively. Only the intermediate value did not present statistically significant differences with the known time of death (p>0.05). Conclusions: The thermal accumulation model using L. eximia as a forensic indicator provided accurate information about the PMI only when samples were collected at 144 hours, which indicates that this method may be accurate and useful during the first stages of cadaveric decomposition.

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Flies are the main competitors of dung beetles for oviposition sites and rolling dung beetles relocate their food to reduce interspecific competition. Furthermore, dung beetles deposit chemical substances on the food ball that may repel fly larvae and certain predators. In the present study, using Deltochilum furcatum, a dung beetle that does not exhibit parental care and the blow-fly, Lucilia cuprina, we tested the hypothesis that pygidial secretions deposited on the food ball could also make it less attractive as an oviposition site for flies. Food balls rolled by either D. furcatum males or females received significantly fewer eggs that balls that had not been rolled by beetles. Also, flies laid significantly fewer eggs on food balls treated with secretions collected from male pygidial glands. Reduced fly oviposition may be a direct effect of compounds the beetles deposited, acting as an allomone, and/or an indirect negative effect on the microbial community that stimulates fly oviposition. A model of the reproductive biology of this species is proposed.

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Resumen Las miasis son infestaciones parasitarias en humanos y animales causadas por estadios larvarios de moscas; son de distribución mundial y son una enfermedad frecuente en nuestro medio. En la literatura solo existen algunos casos reportados; por lo cual, su verdadera incidencia es difícil de establecer debido al sub-registro y ausencia de tipificación de larvas. Objetivo. Identificar, clasificar y caracterizar morfológicamente las larvas causantes de miasis como base para futuras aplicaciones e intervenciones en salud pública. Materiales y métodos. Se analizaron 262 larvas obtenidas del cepario de la Universidad Colegio Mayor de Cundinamarca que se encontraban almacenadas sin ningún tipo de identificación, organización e historia. Resultados. Se realizó la identificación con estereoscopio y claves dicotómicas de las familias Cuterebridae, Oestridae y Calliphoridae. Las especies encontradas son asociadas a diferentes tipos de miasis humana y animal, entre ellas; Dermatobia hominis, Dermatobia cyaniventris, Oestrus ovis, Cochliomyia hominivorax y Lucilia sp. Discusión. Las formas más comunes de este parasitismo son cavitarias y forunculares; causadas por Dermatobia hominis y Cochliomyia hominivorax, sin embargo, éstas no son de reporte obligatorio ante los servicios médicos humanos. Por lo tanto, es indispensable la información y capacitación de profesionales de la salud para la correcta conservación, identificación y reporte de las larvas extirpadas en pacientes con miasis, hasta el punto de ser considerada una práctica de rutina en el diagnóstico clínico.

Abstract Myiasis is the parasitic infestation of the body in humans and animals caused by larval stages of flies; such diseases are worldwide distributed and they are frequent in our environment. In the literature, there are only a few reports; therefore, its real incidence is difficult to be established due to sub-recorded cases and absence of larval typing. Objective. To identify, classify and morphologically characterize myasis-producing larvae of importance in public health. Material and methods. 262 larvae were analysed, obtained from the Universidad Colegio Mayor de Cundinamarca that were stored without any identification, organization and history. Results. Larvae were identified using a stereomicroscope and morphology was based on dichotomous keys of the Cuterebridae, Oestridae and Calliphoridae families. The species found are associated with different types of myiasis, including; Dermatobia hominis, D. cyaniventris, Oestrus ovis, Cochliomyia hominivorax, C. macellaria and Lucilia spp. Discussion. As a conclusion, we found that cavitary and foruncular were the most common forms of this parasitism in the collection from the Universidad Colegio Mayor de Cundinamarca. and that Dermatobia hominis and Cochliomyia hominivorax were the main involved species; however, these are not mandatory reporting species for medical services. Therefore, generating information about preservation, identification and recording of myasis-producing larvae, as well as training of professionals in public health might be considered as a routine practice for an accurate clinical diagnosis.

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This study's main objective was to evaluate the action of larval therapy derived from Lucilia sericata and Sarconesiopsis magellanica (blowflies) regarding Leishmania panamensis using an in vivo model. Eighteen golden hamsters (Mesocricetus auratus) were used; they were divided into 6 groups. The first three groups consisted of 4 animals each; these, in turn, were internally distributed into subgroups consisting of 2 hamsters to be used separately in treatments derived from each blowfly species. Group 1 was used in treating leishmanial lesions with larval therapy (LT), whilst the other two groups were used for evaluating the used of larval excretions and secretions (ES) after the ulcers had formed (group 2) and before they appeared (group 3). The three remaining groups (4, 5 and 6), consisting of two animals, were used as controls in the experiments. Biopsies were taken for histopathological and molecular analysis before, during and after the treatments; biopsies and smears were taken for assessing parasite presence and bacterial co-infection. LT and larval ES proved effective in treating the ulcers caused by the parasite. There were no statistically significant differences between the blowfly species regarding the ulcer cicatrisation parameters. There were granulomas in samples taken from lesions at the end of the treatments. The antibacterial action of larval treatment regarding co-infection in lesions caused by the parasite was also verified. These results potentially validate effective LT treatment against cutaneous leishmaniasis aimed at using it with humans in the future.

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El uso de moscas y otros artrópodos como evidencia para calcular la data de muerte de un cuerpo en estado avanzado de putrefacción, se conoce como entomología forense, una disciplina auxiliar de las ciencias forenses. La presencia de larvas sobre el cuerpo humano sin vida, permite al entomólogo forense apoyar al patólogo, estableciendo los márgenes mínimo de tiempo de muerte transcurridos desde la llegada de los insectos al cuerpo hasta el momento del hallazgo. En este estudio, se presenta un listado de dípteros de importancia médico legal colectadas en las adyacencias de la morgue del Hospital Adolfo Prince Lara, municipio Puerto Cabello. En los meses enero-marzo 2012 se realizaron tres colectas, una por mes. Las moscas se capturaron con el uso de una malla entomológica utilizando como cebo 500 g de hígado de res en estado cromático de descomposición. En cada colecta se tomaron datos de temperatura y humedad relativa (promedio = 30ºC y 48%, respectivamente). Se recolectaron un total de 257 individuos correspondientes a las familias Piophilidae (1,1%), Sarcophagidae (4,1%), Phoridae (10,2%), Muscidae (32,3%) y Calliphoridae (52,3%).Sin embargo, la especie más representativa durante el muestreo en las adyacencias del hospital fue L. cuprina, seguida de C. megacephala.

The use of flies and other arthropods as evidence to estimate the time of death of a body in an advanced state of putrefaction, known as forensic entomology, an auxiliary discipline of forensic science. The presence of larvae on the human body lifeless, allows the forensic entomologist support the pathologist, establishing minimum time frames death since the arrival of the insects to the body until the moment of discovery. In this study, a list of Diptera of forensic importance collected in the vicinity of the hospital Adolfo Prince Lara, Puerto Cabello morgue are presented. In the months January to March 2012 were made three collections, one per month. Using 500 g of beef liver decomposed (in chromatics stage) the flies were taken temperature and relative humidity (mean = 30 and 48%, respectively). A total of 257 individuals corresponding to families Piophilidae (1.1%), Sarcophagidae (4.1%), Phoridae (10.2%), Muscidae (32.3%) and Calliphoridae (52.3%). However, the most representative species during sampling in the vicinity of the was L. cuprina, followed by C. megacephala.

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Larval therapy is used as alternative treatment for hard-to-heal chronic and infected wounds. Lucilia sericata is the most used blowfly species. However, it has been shown recently that Sarconesiopsis magellanica larval excretions and secretions have potent antibacterial activity; this blowfly belongs to the Calliphoridae family. The present work has dealt with evaluating larval therapy using S. magellanica on wounds induced in diabetic rabbits and its action was compared to the effect induced by L. sericata. Twelve New Zealand White rabbits (Oryctolagus cuniculus) were used; they were divided into 4 groups, the first two being treated with larval therapy derived from both aforementioned necrophagous blowflies, an antibiotic was used in the third and the fourth was used as control. All the animals were wounded on the back and infected with Pseudomonas aeruginosa and Staphylococcus aureus. Samples of the secretion from each animal's infected wound were taken and sown on blood agar. The colony forming units were then counted. The PUSH scale was used for the macroscopic evaluation of the wounds. Bacterial control was encountered 48 h post-treatment in the treatments involving larval therapy and to a lesser extent with the antibiotic. Likewise, wound debridement was quicker and more efficient with larval therapy compared to the antibiotic group; however, wound closing time was 23 days in all treatments. The group treated with S. magellanica larvae had relatively quicker evolution until the proliferation phase and the start of maturation, even though there were no significant differences between both blowfly species evaluated here regarding treatments by the end of the treatment period. The present study has validated the diabetic rabbit model for inducing chronic wounds regarding larval therapy and has likewise confirmed the effectiveness of S. magellanica-derived larval therapy as an alternative for curing and healing wounds.

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The blowfly Lucilia cuprina is an economically important livestock pest that is also associated with human myiasis. To date, methods including the application of chemical pesticides, plant extracts, insect growth regulators and a range of Bacillus thuringiensis strains have been used, with varying degrees of success, to control this pest. The present study evaluated the larvicidal activity and the induction of sub lethal effects upon post embrionary development following ingestion of 12 strains of Brevibacillus laterosporus, presented individually in the diet as spores. All strains were shown to be larvicidal, with corrected mortality levels of 29 to 54%. No significant differences were observed, in terms of larval weight at the time of abandoning the diet, in the time taken for the initiation of the pupation process, in the duration of the pupation process, the period of adult emergence or cumulative mortality during the transition from larvae to adult. However, an influence upon sex ratio was observed. This study suggests that strains of B. laterosporus hold potential for development as a tool in the biological control of L. cuprina.

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Objetivo: Evaluar, en condiciones in vitro , la actividad antibacterial de los extractos de cuerpos grasos y de la hemolinfa de larvas de tercer estadio de Sarconesiopsis magellanica , la cual se comparó con los efectos obtenidos de las mismas sustancias derivadas de Lucilia sericata . S. magellanica (Diptera: Calliphoridae) es una mosca de importancia principalmente forense, utilizada en la determinación del intervalo post mortem . Por sus hábitos necrófagos, es considerada un modelo potencialmente útil en terapia larval. Material y métodos: Se extrajeron los cuerpos grasos de las larvas mediante la técnica de disección corporal y la hemolinfa se obtuvo mediante decapitación y centrifugación de los especímenes larvales. Las bacterias evaluadas fueron Staphylococcus aureus y Pseudomonas aeruginosa . Los métodos utilizados para evaluar la actividad antibacterial fueron difusión en agar y unidades formadoras de colonias (UFC/ml). Resultados: Después de la correspondiente incubación, los resultados generales mostraron que la actividad antibacterial de la hemolinfa y de los cuerpos grasos, tanto de L. sericata como de S. magellanica , fueron efectivos contra S. aureus y P. aeruginosa sin diferencias significativas entre las especies de moscas, aunque con algunas diferencias entre las cepas bacterianas. Conclusiones: Los resultados obtenidos sugieren que estas sustancias podrían tener un efecto similar en el tratamiento de heridas infectadas contra los microorganismos evaluados.

Objective: This study aimed to evaluate the in vitro antibacterial activity of fat body and hemolymph extracts from Sarconesiopsis magellanica (Diptera: Calliphoridae) third-instar larvae, compared to the effect obtained using the same extracts but derived from Lucilia sericata . S. magellanica blowflies are considered important in forensic sciences due to their usefulness in determining the post mortem interval. This blowfly could be useful in larval therapy due to its necrophagous habits. Materials and methods: Fat body from larvae was removed by dissection, and hemolymph via decapitation and centrifugation of larval specimens. The antibacterial effect was tested against Staphylococcus aureus and Pseudomonas aeruginosa using two methods: agar diffusion and colony forming units (CFU/mL). Results: Hemolymph and fat body extracts derived from both L. sericata and S. magellanica were effective against S. aureus and P. aeruginosa , with no significant differences between blowfly species, although with some differences between the bacterial strains. Conclusions: The results obtained suggest that S. magellanica and L. sericata fat body and hemolymph extracts might have a similar antimicrobial activity against these microorganisms when used to treat infected wounds.

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Objetivo: desarrollar un método de tratamiento de huevos de Lucilia eximia para la obtención de larvas estériles y evaluar la capacidad de supervivencia de dichas larvas en condiciones de refrigeración a 4°C. Métodos: se estableció un sistema de crianza para L. eximia. Los huevos fueron colectados en el sustrato de oviposición, se lavaron con solución salina estéril (0,85%), se trataron con hipoclorito de sodio (0,5%) y finalmente se esterilizaron con formalina, evaluando tres diferentes concentraciones (2,5%; 5,0% y 10,0%). Se verificó la esterilidad de los huevos empleando medios de cultivo bacteriológicos y la eclosión de los huevos esterilizados fue expresada mediante el cálculo de un índice de eclosión (IE). Además, se evaluó la supervivencia de las larvas de segundo y tercer estadio temprano (L2 y L3, respectivamente) en condiciones de refrigeración, durante las 4 primeras horas y luego a las 24 y 48 horas. Resultados: todas las concentraciones de formalina evaluadas fueron capaces de esterilizar los huevos. No se encontró una correlación entre el IE y las concentraciones de formalina utilizadas (R Spearman = -0,030, p = 0,848). Durante las primeras 4 horas a 4°C, un 100% de las L2 y las L3 sobrevivieron. Sin embargo, en ambos estadios larvales hubo un marcado descenso de la supervivencia a las 24 y 48 horas, siendo las L2 las más sensibles a las condiciones de refrigeración. Conclusiones: los resultados mostraron que la obtención de larvas estériles de L. eximia con el método utilizado es un proceso sencillo, pero la supervivencia de las larvas en condiciones de refrigeración es limitada.

Objective: develop a method to treat eggs of Lucilia eximia to obtain sterile larvae and evaluate the survival capacity of those larvae under refrigeration at 4°C. Methods: a rearing system was set up for L. eximia. The eggs were collected from the oviposition substrate, washed with sterile saline solution (0.85%), treated with sodium hypochlorite (0.5%), and sterilized with formalin. Three concentrations were evaluated: 2.5%; 5.0% and 10.0%. Egg sterility was verified by bacteriological culture. Eclosion of sterilized eggs was expressed by estimation of an eclosion rate (ER). An evaluation was conducted of the survival of larvae from the second and third early stages (L2 and L3, respectively) under refrigeration during the first 4 hours and then at 24 and 48 hours. Results: all the formalin concentrations evaluated were capable of sterilizing the eggs. No correlation was found between the ER and the formalin concentrations used (Spearman's Rho = -0.030, p = 0.848). During the first 4 hours at 4°C, 100% L2 and L3 survived. However, both larval stages showed a marked decrease in survival at 24 and 48 hours, L2 being the most sensitive to refrigeration. Conclusions: results show that obtaining sterile L. eximia larvae by this method is a simple process. However, larval survival under refrigeration is limited.

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Larval interactions of dipteran species, blow flies in particular, were observed and documented daily over time and location on five black bear carcasses in Gainesville, FL, USA, from June 2002 - September 2004. Cochliomyia macellaria (Fabricius) or Chrysomya megacephala (Fabricius) larvae were collected first, after which Chrysomya rufifacies (Macquart) oviposited on the carcasses in multiple locations (i.e., neck, anus, and exposed flesh) not inhabited already by the other blow fly larvae. Within the first week of decomposition, C. rufifacies larvae grew to ≥12 mm, filling the carcasses with thousands of larvae and replacing the other calliphorid larvae either through successful food source competition or by predation. As a result, C. macellaria and C. megacephala were not collected past their third instar feeding stage. The blow fly species, C. megacephala, C. macellaria, Lucilia caeruleiviridis (Macquart), Phormia regina (Meigen), Lucilia sericata (Meigen), and C. rufifacies, completed two developmental cycles in the 88.5-kg carcass. This phenomenon might serve to complicate or prevent the calculation of an accurate postmortem interval.

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Introducción: Lucilia sericata es una especie de importancia médica y forense, utilizada en terapia larval para curar heridas crónicas y en estudios médico-legales empleada en la estimación del intervalo post mórtem y el traslado de cadáveres. No existen registros de las características citogenéticas de esta mosca en el neotrópico. El objetivo principal de este trabajo fue identificar las características morfométricas cromosómicas y las estructuras primarias del cariotipo, a partir de especímenes de L. sericata de la cepa Bogotá, Colombia. Materiales y métodos: Se tomaron huevos embrionados, que fueron previamente esterilizados en su superficie, se maceraron y luego fueron sembrados en el medio de cultivo L-15, suplementado con 20% de SFB, e incubados a una temperatura de 28 °C, sin atmosfera de C0(2). La preparación de los cromosomas se obtuvo de monocapas celulares semiconfluentes, empleando diversas soluciones: antimitótica (Colchicina), hipotónica (KCl 0,075 M) y fijadora (Carnoy: metanol y ácido acético; 3:1). Se llevó a cabo la técnica de bandeo C para la identificación de regiones cromosómicas de heterocromatina constitutiva. Resultados: Se obtuvieron parámetros morfométricos de cada par cromosómico. El número diploide del cariotipo obtenido de los cultivos celulares fue 2n = 12; éstos se clasificaron morfológicamente, de acuerdo con patrones previamente establecidos, así: los pares I, II, IV y V fueron metacéntricos, y el par III fue submetacéntrico. A su vez, el par sexual fue heteromórfico, siendo el cromosoma X metacéntrico y el cromosoma Y submetacéntrico. El bandeo C fue positivo para todos los pares cromosómicos. Conclusiones: Se establecieron las características citogenéticas de L. sericata, cepa Bogotá, Colombia, relacionadas con número, forma, tamaño, posición del centrómero y regiones heterocromáticas de los cromosomas.

Objective: Lucilia sericata is an important species for medical and forensic purposes, it is used in maggot therapy in the treatment of chronic wounds and in medical-legal studies for establishing the post-mortem interval and the transfer of corpses. Currently there are no records of the cytogenetic characteristics of this fly in Neotropical region. The main objective of this study was to identify morphometric characteristics and primary structures from karyotype of L. sericata strain Bogota, Colombia. Methods and materials: Embryonated eggs were taken, which were previously surface sterilized, macerated and then seeded in L-15 medium culture, supplemented with 20% FBS and incubated at 28 °C, without C0(2) atmosphere. The preparation of chromosomes was obtained from semiconfluent monolayers, pretreated with various solutions: antimitotic (Colchicine), hypotonic (KCl 0.075 M) and fixative (Carnoy, methanol and acetic acid, 3:1). C-banding technique was carried out to identify chromosomal regions of constitutive heterochromatin. Results: Morphometric parameters were obtained from each pair of chromosomes. The diploid karyotype number obtained from cell cultures was 2n = 12; they were classified morphologically, according to patterns established previously, as follows: pairs I, II, IV and V were metacentric and pair III was submetacentric. On the other hand, the sexual pair was heteromorphic, being X chromosome metacentric and Y chromosome submetacentric. C banding was positive for all chromosome pairs. Conclusions: The cytogenetic characteristics of L. sericata, strain Bogotá, were established according to number, shape, centromer position and heterochromatic regions.

Introdução: Lucilia sericata é uma espécie de importência médica e forense, utilizada em terapia larval para curar feridas crônicas e em estudos médico-legais empregada na estimação do intervalo post morteme o traslado de cadáveres. Não existem registros das características citogéneticas desta mosca no neotrópico. O objetivo principal deste trabalho foi identificar as características morfométricas cromossômicas e as estruturas primárias do cariótipo, a partir de especímenes de L. sericata da cepa Bogotá, Colômbia. Materiais e métodos: Tomaram-se ovos embrionados, que foram previamente esterilizados em sua superfície, se maceraram e depois foram semeados no médio de cultivo L-15, suplementado com 20% de SFB, e incubados a uma temperatura de 28 °C, sem atmosfera de C02. A preparação dos cromossomas obteve-se de monocamadas celulares semiconfluentes, utilizando diversas soluções: antimitótica (Colchicina), hipotônica (KCl 0,075 M) e fixadora (Carnoy: metanol y ácido acético; 3:1). Levou-se a cabo a técnica de bandas C para a identificação de regiões cromossômicas de heterocromatina constitutiva. Resultados: Se obtiveram parâmetros morfométricos de cada par cromossômico. O número diplóide do cariótipo obtido dos cultivos celulares foi 2n = 12; estes se classificaram morfologicamente, de acordo com patrões previamente estabelecidos, assim: os pares I, II, IV e V foram metacêntricos, e o par III foi submetacéntrico. Por sua vez, o par sexual foi heteromórfico, sendo o cromossoma X me-tacêntrico e o cromossoma Y submetacêntrico. As bandas C foram positivas para todos os pares cromossômicos. Conclusões: Se estabeleceram as características citogenéticas de L. sericata, cepa Bogotá, Colômbia, relacionadas com número, forma, tamanho, posição do centrômero e regiões heterocromáticas dos cromossomas.

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Background: Myiasis is one of the main causes of infestation by Diptera larvae in animals and human beings. This parasitic disease is frequently diagnosed at veterinary and medical practices. It is classified according to its anatomical location in the host or to its dependency relations and parasitic occurrence. In Brazil, the two diptera species with the highest myiasis incidence in domestic animals are Cochliomyia hominivorax (Calliphoridae) and Dermatobia hominis (Oestridae). These ectoparasites are primarily found in dogs and secondarily in cats, and they are often associated with omission or mistreatment by the owner. This study describes myiasis cases and the main predisposing factors in domestic animals that occurred in 2009 in the Federal District, Brazil. Materials, Methods & Results: Between January and December 2009, veterinary practitioners from 90 small animal practices were requested to supply the larvae collected from clinical myiasis cases. The larvae were kept alive inside biological containers containing vermiculite to preserve their integrity during transportation. Data on the collection month, age, gender, breed, color and type of coat, as well as lesion site, myiasis type and dwelling type were obtained. The larvae were identified in laboratory and then kept inside incubators, fed on rotten bovine meat during 24h. The resulting flies were again identified and sexed. Then the absolute and relative proportions of the clinical cases were obtained, based on the epidemiological factors and respective parasites. Forty cases were recorded (39 of which were dogs and one was a cat). Cochliomyia hominivorax was the most abundant parasite, with 37 cases observed in dogs and only one in a cat. The other two myiasis cases were caused by Lucilia eximia and Musca domestica. In dogs, the highest occurrence of myiasis was observed in males, especially in German Sheepdogs and Cocker Spaniels. The predominant anatomical sites of the disease in dogs were the front limbs and tail. The period in which the disease occurred most frequently was between March and May, period which corresponds to the rainy season in the Brazilian Cerrado. Dogs living in houses within urban areas had the highest parasitism occurrence. Discussion: Myiasis in companion animals is a common finding throughout practices in Brazil and around the world. However, this situation has been under control in North American countries, especially after erradication of myiases caused by C. hominivorax in bovines, which represented great economic losses. Therefore, the incidence of the parasitism in dogs and cats was reduced. In Brazil, obligatory and facultative cutaneous myiases in dogs and cats are caused by omission and mistreatment by the owner. The results presented in this study corroborate the characteristics of neotropical myiases in the Southeast and South region of Brazil in relation to the incidence period and preferential host characteristics, except that the disease has a preference for male light-colored animals, being predominantly observed on the hind limbs. New cases were observed in dogs, particularly in Central Brazil, such as the facultative cutaneous myiasis cases caused by Lucilia eximia and Musca domestica.

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Background: Myiasis is one of the main causes of infestation by Diptera larvae in animals and human beings. This parasitic disease is frequently diagnosed at veterinary and medical practices. It is classified according to its anatomical location in the host or to its dependency relations and parasitic occurrence. In Brazil, the two diptera species with the highest myiasis incidence in domestic animals are Cochliomyia hominivorax (Calliphoridae) and Dermatobia hominis (Oestridae). These ectoparasites are primarily found in dogs and secondarily in cats, and they are often associated with omission or mistreatment by the owner. This study describes myiasis cases and the main predisposing factors in domestic animals that occurred in 2009 in the Federal District, Brazil. Materials, Methods & Results: Between January and December 2009, veterinary practitioners from 90 small animal practices were requested to supply the larvae collected from clinical myiasis cases. The larvae were kept alive inside biological containers containing vermiculite to preserve their integrity during transportation. Data on the collection month, age, gender, breed, color and type of coat, as well as lesion site, myiasis type and dwelling type were obtained. The larvae were identified in laboratory and then kept inside incubators, fed on rotten bovine meat during 24h. The resulting flies were again identified and sexed. Then the absolute and relative proportions of the clinical cases were obtained, based on the epidemiological factors and respective parasites. Forty cases were recorded (39 of which were dogs and one was a cat). Cochliomyia hominivorax was the most abundant parasite, with 37 cases observed in dogs and only one in a cat. The other two myiasis cases were caused by Lucilia eximia and Musca domestica. In dogs, the highest occurrence of myiasis was observed in males, especially in German Sheepdogs and Cocker Spaniels. The predominant anatomical sites of the disease in dogs were the front limbs and tail. The period in which the disease occurred most frequently was between March and May, period which corresponds to the rainy season in the Brazilian Cerrado. Dogs living in houses within urban areas had the highest parasitism occurrence. Discussion: Myiasis in companion animals is a common finding throughout practices in Brazil and around the world. However, this situation has been under control in North American countries, especially after erradication of myiases caused by C. hominivorax in bovines, which represented great economic losses. Therefore, the incidence of the parasitism in dogs and cats was reduced. In Brazil, obligatory and facultative cutaneous myiases in dogs and cats are caused by omission and mistreatment by the owner. The results presented in this study corroborate the characteristics of neotropical myiases in the Southeast and South region of Brazil in relation to the incidence period and preferential host characteristics, except that the disease has a preference for male light-colored animals, being predominantly observed on the hind limbs. New cases were observed in dogs, particularly in Central Brazil, such as the facultative cutaneous myiasis cases caused by Lucilia eximia and Musca domestica.(AU)

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La terapia larval es utilizada desde los años 30 del siglo pasado para la remoción del tejido necrótico en el tratamiento de úlceras crónicas infectadas logrando con ello promover la formación de tejido granuloso para el crecimiento de piel sana; especialmente a partir de la aparición de la resistencia a los antibióticos se la reconoce como una alternativa eficaz. Se presentan los resultados de la aplicación de la terapia larval en 42 pacientes con úlceras de diferentes orígenes, utilizando, como una nueva alternativa en larviterapia, la especie Lucilia eximia. Se presenta documentación fotográfica de la aplicación de esta terapia en cuatro casos.

Larval therapy is used in the treatment of infected chronic wounds by allowing the removal ofnecrotic tissue, which induces the formation of granular tissue and the growth of healthy skin.Considering the increasing prevalence of antibiotic resistance, this type of therapy may be an effectivealternative in the management of infected chronic wounds. In this article we report the use ofmaggot therapy using the Lucilia eximia species in 42 patients with chronic skin wounds associatedto different pathologies including: venous and arterial ulcers, diabetic foot, sickle cell disease,vasculopathy, elephantiasis, Berger disease, pyoderma gangrenosum (PG), traumatic wounds, erysipelas, and hospital acquired infections. Four cases are depicted photographically.

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The objective of this work was to establish, under experimental laboratory conditions, a colony of Lucilia sericata, Bogotá-Colombia strain, to build life tables and evaluate two artifcial diets. This blowfy is frequently used in postmortem interval studies and in injury treatment. The parental adult insects collected in Bogotá were maintained in cages at 22°C±1 average temperature, 60 percent±5 relative humidity and 12 h photoperiodicity. The blowfies were fed on two artifcial diets that were evaluated over seven continuous generations. Reproductive and population parameters were assessed. The life cycle of the species was expressed in the number of days of the different stages: egg = 0.8±0.1, larvae I = 1.1±0.02, larvae II = 1.94±0.16, larvae III = 3.5±0.54, pupae = 6.55±0.47, male adult = 28.7±0.83 and female adult = 33.5±1.0. Total survival from egg stage to adult stage was 91.2 percent for diet 1, while for diet 2 this parameter was 40.5 percent. The lifetime reproductive output was 184.51±11.2 eggs per female. The population parameters, as well as the reproductive output of the blowfies that were assessed, showed relatively high values, giving evidence of the continuous increase of the strain over the different generations and making possible its maintenance as a stable colony that has lasted for more than two years.

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El propósito principal de la investigación aquí presentada fue obtener cultivos celulares primarios derivados de Lucilia sericata (Diptera: Calliphoridae). Esta mosca necrófaga es utilizada para determinar el intervalo post-mortem y en terapia larval. A partir de huevos embrionados, se realizaron explantes en diversos medios de cultivo (Grace, Schneider, MM/VP12, DMEM, Grace/L-15 y L-15), suplementados con 20% de suero fetal bovino. La esterilización del material biológico se efectuó mediante la aplicación de soluciones de formaldehido e hipoclorito de sodio. El crecimiento celular se inicio en los medios L-15, MM/VP12, Grace/L-15 y Schneider, en un tiempo promedio de 10 días después de efectuadas las siembras de tejidos embrionarios, mediante la proliferación de grupos de colonias dispersas en la superficies de los frascos de cultivo y a partir de las terminaciones de los fragmentos larvales. La evolución del crecimiento celular hasta la formación de la monocapa semiconfluente fue relativamente rápida, se alcanzo a las tres semanas post-explantes. La morfología de las células en los cultivos fue heterogénea, se destacaron formas epitelioides, similares a nerviosas, gigantes e irregulares. La comparación de las características de crecimiento de los cultivos celulares de L. sericata con los obtenidos de otras especies de dípteros mostro mayor favorabilidad en la evolución, en razón a que las células se adaptaron mejor a las condiciones fisico-quimicas de varios medios de cultivo. Este es el primer informe de cultivos celulares de una mosca de la familia Calliphoridae.

The main purpose of this study was to obtain primary cell cultures derived from Lucilia sericata (Diptera: Calliphoridae). Necrophagous this fly is used for determination of post-mortem interval and larval therapy. Since explants embryonated eggs were performed in various culture media (Grace Schneider, MM/VP12, DMEM, Grace/L-15 and L-15), supplemented with 20% fetal serum. Sterilization of the biological material was carried out by immersing it in formaldehyde and sodium hypochlorite solutions. The cell growth was initiated in the L-15, MM/VP12, and Schneider Grace/L-15 in an average time of 10 days after completion of planting by the proliferation of groups of colonies scattered on the surface of the boxes crops and also from the endings of larval fragments. The evolution of cell growth to the formation of monolayer semi-confluent was relatively fast, reaching at 3 weeks post-explant. Cellular morphology in cultured cells was heterogeneous, especially epithelioid forms, similar to nerve, giant and irregular. Comparison of the growth characteristics of these cell cultures with those obtained from other species of flies was more favorable in the evolution of those obtained from L. sericata, on the grounds that the cells are better adapted to the physical-chemical conditions of several culture media. This is the first report of a cell culture-fly family Calliphoridae.

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