Técnicas moleculares integradas a la vigilancia entomológica de vectores de la enfermedad de Chagas: Estudio del vector secundario Triatoma sordida en la Región Oriental del Paraguay / Molecular techniques integrated to the entomological surveillance of Chagas disease vectors: Study of the secondary vector Triatoma sordida in the Eastern Region of Paraguay

Las técnicas moleculares para la detección de infección natural y fuente de alimentación en vectores secundarios de la enfermedad de Chagas cuando son aplicadas a ejemplares capturados en áreas endémicas, históricamente ocupadas por Triatoma infestans, proporcionan a las investigaciones epidemiológicas respuestas más exactas con relación a la transmisibilidad de la enfermedad. El presente estudio tiene como objetivo emplear biomarcadores moleculares para evaluar el impacto de la infestación intra y peridomicilar de Triatoma sordida en viviendas bajo vigilancia entomológica de departamentos de la Región Oriental del Paraguay en el período 2007 al 2015. Un total de 559 ejemplares de T. sordida capturados en 253, 91 y 52 viviendas de los departamentos Paraguarí, San Pedro y Cordillera, respectivamente fueron analizados. La infestación detectada fue del 24% al 48% así como una elevada colonización intradomiciliar del 5% al 36% en los tres departamentos. La detección molecular de infección natural osciló entre el 14% y 44%; y en 111 ejemplares se determinó la fuente de alimentación. El marcador molecular citocromo b permitió demostrar por vez primera un elevado porcentaje de triatominos con sangre humana como fuente de alimentación, principalmente en Cordillera con un 82% (28/34 T. sordida capturados). Estos hallazgos dejan en evidencia el avance del T. sordida en la ocupación del nicho ecológico de T. cruzi y la capacidad de esta especie secundaria como vector en la transmisión de T. cruzi en comunidades de la Región Oriental

When molecular techniques for the detection of natural infection and blood meal source in secondary vectors of Chagas disease are applied to specimens captured in endemic areas, historically occupied by Triatoma infestans, provide more accurate answers to questions about transmissibility of the illness and further contribute to the epidemiological studies. The aim of this study was to evaluate the impact of intra and peridomiciliary infestation of Triatoma sordida in households from the departments of the Eastern Region of Paraguay, under entomological surveillance during the period 2007 to 2015, by using the molecular biomarkers technology. A total of 559 specimens of T. sordida captured in 253, 91 and 52 households from Paraguarí, San Pedro and Cordillera departments, respectively, were analyzed. The infestation detected was from 24% to 48% as well as a high intradomicialiary colonization from 5% to 36% in the three departments. The molecular detection of natural infections ranged from 14% to 44% and in 111 specimens the meal source was identified. The molecular marker cytochrome b allowed to demonstrate, for the first time, high frequency of triatomines with human blood as a food source, mainly in Cordillera as it was determined in 82% (28/34) of the T. sordida captured. These findings demonstrate a progress of T. sordida into the ecological niche of T. cruzi and the abillity of this secondary species as a vector of the transmission of T. cruzi in communities from the Eastern Region of Paraguay

An overview of the sandfly fauna (Diptera: Psychodidae) followed by the detection of Leishmania DNA and blood meal identification in the state of Acre, Amazonian Brazil

BACKGROUND In Acre state, Brazil, the dissemination of cutaneous leishmaniasis has increased in recent years, with limited knowledge of the potential Leishmania spp. vectors involved. OBJECTIVES Here, data concerning the sandfly fauna of Brasiléia municipality, Leishmania DNA-detection rates and the identification of blood meal sources of insects captured in 2013-2015 are presented. METHODS Parasite detection in female sandflies was performed individually by multiplex polymerase chain reaction (PCR) (Leishmania kDNA/sandfly cacophony-gene), with the identification of Leishmania spp. by hsp70-PCR and sequencing. The identification of blood gut-content from fed females was performed by cyt b-PCR and sequencing. FINDINGS A total of 4,473 sandflies were captured. A subgroup of 864 non-blood-fed females evaluated for the presence of Leishmania DNA showed 2.9% positivity for Leishmania (Viannia) braziliensis and L. (V.) guyanensis. The identification of blood meal sources was performed in 96 blood-fed females, allowing the identification of 13 vertebrate species. In nine/96 fed females, DNA from L. (V.) shawi, L. (V.) guyanensis, L. (V.) braziliensis and Endotrypanum sp. was detected. MAIN CONCLUSIONS In Brumptomyia sp. and Evandromyia termitophila, the first report of Leishmania DNA-detection is provided in Acre; Nyssomyia shawi is implicated as potential vector of L. (V.) braziliensis and L. (V.) guyanensis for the first time in Brazil.

Identification of sandflies (Diptera: Psychodidae: Phlebotominae) blood meals in an endemic Leishmaniasis area in Brazil / Identificação do repasto sanguíneo de flebotomíneos (Diptera: Psychodidae: Phlebotominae) provenientes de área endêmica de Leishmaniose no Brasil

SUMMARYThe aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis(82.1%) and Lutzomyia cortelezzii(17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission.

RESUMOO objetivo deste estudo foi identificar o repasto sanguíneo de fêmeas de flebotomíneos capturadas no município de Governador Valadares, área endêmica de leishmaniose visceral e tegumentar no Estado de Minas Gerais, Brasil. Entre maio de 2011 e janeiro 2012 foram realizadas capturas com armadilhas luminosas HP em quatro bairros. Foram capturados 2.614 exemplares (2.090 machos e 524 fêmeas). Noventa e sete fêmeas ingurgitadas foram identificadas como pertencentes às espécies Lutzomyia longipalpis(82,1%) e Lutzomyia cortelezzii(17,9%). Considerando a alimentação simples e a mista, o ensaio imunoenzimático revelou em Lutzomyia longipalpisuma predominância de sangue de galinhas (43,6%), mostrando o importante papel que galinhas podem exercer no peridomicílio, aumentando a chance de contato dos flebotomíneos com outros vertebrados e, consequentemente, o risco de transmissão da leishmaniose.

Analysing Host Preference Behavior of Phlebotomus argentipes (Diptera: Psychodidae) Under the Impact of Indoor Residual Spray.

Background: Present scenario of Bihar and neighboring Indian states reveals dichlorodiphenyltrichloroethane (DDT) being an insecticide of choice for controlling the vector of Indian Visceral Leishmaniasis (VL) i.e., Phlebotomus argentipes, that had reported to attain resistance/tolerance against it, leading to the behavioral transition including host preference and selection by them. The relationship between insecticidal resistance and host preference/ selection is not yet well understood. Objective: Exploring the host preference/selection behavior under the influence of insecticidal pressure in different biotopes of VL endemic regions in India Methods: For this, the engorged sand flies that were collected before and after Indoor Residual Spray (IRS) were subjected for feeding behavior analysis. The parameter studied were Host Feeding Index (HFI) and Forage Ratio (FR) by analyzing Blood Meal Identification (BMI). Results: The higher percentage of sand flies were recorded to be fed on cattle host (56.05%) with respect to the human host (30.35%) before IRS while a significant increase in cattle blood index (79.17%) in contrast to significant drop in human blood index (9.43%) was recorded during post IRS session at the study site. It establishes, cattle being potentially served as a preferred host for sand flies in contrast to other available hosts. The lowered value of FR during pre- and post-IRS respectively for human (0.77 and 0.24) as compared to the cattle (1.89 and 2.67) indicates cattle host being selectively preferred by the P. argentipes also corroborate with the results of BMI. Conclusion: Through the study we can conclude that instead of being killed by IRS, P. argentipes has attained resistance against DDT. Under the insecticidal pressure the host preference as well as selection tendency of P. argentipes for cattle host gets enhanced under the influence of IRS, as abrupt increment was observed in the FR’s post-IRS. While, the avoidance tendency of insects from the human hosts in favor of other available hosts’ viz., cattle, goat, pigs, etc. with slight decrement in the forage ratios for the human hosts during the IRS was also observed. Thus, under the impact of IRS, P. argentipes has changed its behavior from endophilic to exophilic and migrated from the human hosts at the periphery area of sprayed houses towards much safer zone, i.e., deserted houses, nearby gardens, bushes, etc for their survival for feeding cattle i.e., preferred host, lying in unsprayed horizon. Therefore, change in control strategy involving the proper management of insecticide resistance is very much needed to tackle the vector outbreak and hence menace caused by them.

Identification of blood meal sources of Lutzomyia longipalpis using polymerase chain reaction-restriction fragment length polymorphism analysis of the cytochrome B gene

An analysis of the dietary content of haematophagous insects can provide important information about the transmission networks of certain zoonoses. The present study evaluated the potential of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of the mitochondrial cytochrome B (cytb) gene to differentiate between vertebrate species that were identified as possible sources of sandfly meals. The complete cytb gene sequences of 11 vertebrate species available in the National Center for Biotechnology Information database were digested with Aci I, Alu I, Hae III and Rsa I restriction enzymes in silico using Restriction Mapper software. The cytb gene fragment (358 bp) was amplified from tissue samples of vertebrate species and the dietary contents of sandflies and digested with restriction enzymes. Vertebrate species presented a restriction fragment profile that differed from that of other species, with the exception of Canis familiaris and Cerdocyon thous. The 358 bp fragment was identified in 76 sandflies. Of these, 10 were evaluated using the restriction enzymes and the food sources were predicted for four: Homo sapiens (1), Bos taurus (1) and Equus caballus (2). Thus, the PCR-RFLP technique could be a potential method for identifying the food sources of arthropods. However, some points must be clarified regarding the applicability of the method, such as the extent of DNA degradation through intestinal digestion, the potential for multiple sources of blood meals and the need for greater knowledge regarding intraspecific variations in mtDNA.

Kazal-type serine proteinase inhibitors in the midgut of Phlebotomus papatasi

Sandflies (Diptera: Psychodidae) are important disease vectors of parasites of the genus Leishmania, as well as bacteria and viruses. Following studies of the midgut transcriptome of Phlebotomus papatasi, the principal vector of Leishmania major, two non-classical Kazal-type serine proteinase inhibitors were identified (PpKzl1 and PpKzl2). Analyses of expression profiles indicated that PpKzl1 and PpKzl2 transcripts are both regulated by blood-feeding in the midgut of P. papatasi and are also expressed in males, larva and pupa. We expressed a recombinant PpKzl2 in a mammalian expression system (CHO-S free style cells) that was applied to in vitro studies to assess serine proteinase inhibition. Recombinant PpKzl2 inhibited α-chymotrypsin to 9.4% residual activity and also inhibited α-thrombin and trypsin to 33.5% and 63.9% residual activity, suggesting that native PpKzl2 is an active serine proteinase inhibitor and likely involved in regulating digestive enzymes in the midgut. Early stages of Leishmania are susceptible to killing by digestive proteinases in the sandfly midgut. Thus, characterising serine proteinase inhibitors may provide new targets and strategies to prevent transmission of Leishmania.

Leishmania infection and host-blood feeding preferences of phlebotomine sandflies and canine leishmaniasis in an endemic European area, the Algarve Region in Portugal

The Algarve Region (AR) in southern Portugal, which is an international tourist destination, has been considered an endemic region of zoonotic leishmaniasis caused by Leishmania infantum since the 1980s. In the present study, phlebotomine and canine surveys were conducted to identify sandfly blood meal sources and to update the occurrence of Leishmania infection in vectors and dogs. Four sandfly species were captured: Phlebotomus perniciosus, Phlebotomus ariasi, Phlebotomus sergenti and Sergentomyia minuta. In one P. perniciosus female, L. infantum DNA was detected. Blood meal tests showed that this species had no host preferences and was an opportunistic feeder. An overall canine leishmaniasis (CanL) seroprevalence of 16.06% was found; the seroprevalence was 3.88% in dogs housed in kennels and 40.63% in dogs that attended veterinary clinics. The simultaneous occurrence of dogs and P. perniciosus infected with L. infantum in the AR indicates that the region continues to be an endemic area for CanL. Our results reinforce the need for the systematic spatial distribution of phlebotomine populations and their Leishmania infection rates and the need to simultaneously perform pathogen monitoring in both invertebrate and vertebrate hosts to investigate the transmission, distribution and spreading of Leishmania infection.

Blood meal analysis of tabanid fly after it biting the rare Sumatran rhinoceros

<p><b>OBJECTIVE</b>To demonstrate a noninvasive large mammalian genetic sampling method using blood meal obtained from a tabanid fly.</p><p><b>METHODS</b>Blood meal was recovered from the abdomen of an engorged tabanid fly (Haematopota sp.) which was captured immediately after biting a Sumatran rhino in captivity. The blood was applied on to a Whatman FTA(®) blood card. Subsequent laboratory work was conducted to extract, amplify and sequence the DNA from the sample. Validation was done by sampling the hair follicles and blood samples from the rhinoceros and subjecting it to the same laboratory process.</p><p><b>RESULTS</b>BLAST search and constructed phylogenetic trees confirmed the blood meal samples were indeed from the rhino.</p><p><b>CONCLUSIONS</b>This method could be used in the field application to noninvasively collect genetic samples. Collection of tabanids and other haematophagous arthropods (e.g. mosquitoes and ticks) and other blood-sucking parasites (e.g. leeches and worms) could also provide information on vector-borne diseases.</p>

Suplementação de glutamina em dietas elaboradas com ingredientes de origem vegetal e animal para pintos de corte / Supplementation of glutamine in diets with ingredients from animal and vegetable sources for broiler chicks

Foi avaliado o efeito da suplementação da glutamina em dietas contendo ingredientes de origem animal sobre o desempenho e a integridade intestinal de pintos de corte, criados até 21 dias de idade. Os tratamentos constituíram-se de combinações entre tipos de dieta, com ingredientes de origem vegetal ou vegetal+animal e suplementação de glutamina (0,0; 0,5; 1,0 e 2,0%). O delineamento foi em blocos ao acaso em arranjo fatorial 2x4, tipos de ração x percentagem de glutamina, com cinco repetições e 12 pintos por unidade experimental. Não houve efeito da interação tipo de dieta versus suplementação de glutamina sobre o desempenho, e os tratamentos não influenciaram o desempenho de pintos de corte. Houve efeito quadrático da suplementação de glutamina sobre o coeficiente de digestibilidade da proteína bruta. A suplementação com glutamina aumentou altura de vilos e profundidade de cripta no duodeno. A utilização de produtos de origem animal em dietas para pintos na fase inicial não prejudica o desempenho, e a inclusão de glutamina melhora a integridade intestinal.

The effect of glutamine supplementation in diets formulated with animal by-products on the performance and integrity of the small intestine of broiler chicks up to 21 days of age was evaluated. The treatments were the combination of types of diets (only with ingredients from a vegetal source or vegetal plus animal source) and levels of glutamine (0.0; 0.5; 1.0 and 2.0%). The experimental design was randomized blocks in a 2x4 factorial scheme (kinds of diets x levels of glutamine), with five replicates and 12 birds per experimental unit. No interaction between diets and glutamine supplementation and treatment effects on the performance traits were observed during the chick starter phase. There was a quadratic effect of glutamine on the crude protein digestibility coefficient. Birds supplemented with glutamine diets showed higher villus height and crypt depth in the duodenum. Broiler diets formulated with animal ingredients have no effect on chick performance during the initial phase, and glutamine supplementation improved the small intestine integrity.

Temporal differences in blood meal detection from the midguts of Triatoma infestans / Diferencias temporales en la detección de fuentes de alimentación en el contenido intestinal de Triatoma infestans

We used genus/species specific PCRs to determine the temporal persistence of host DNA in Triatoma infestans experimentally fed on blood from six common vertebrate species: humans, domestic dogs, guinea pigs, chickens, mice, and pigs. Twenty third or fourth instar nymphs per animal group were allowed to feed to engorgement, followed by fasting-maintenance in the insectary. At 7, 14, 21, or 28 days post-feeding, the midgut contents from five triatomines per group were tested with the respective PCR assay. DNA from all vertebrate species was detected in at least four of five study nymphs at seven and 14 days post-feeding. DNA of humans, domestic dogs, guinea pigs, pigs, and chickens were more successfully detected (80-100%) through day 21, and less successfully (20-100%) at day 28. Findings demonstrate that species-specific PCRs can consistently identify feeding sources of T. infestans within two weeks, a biologically relevant time interval.

Se utilizó pruebas PCR género o especie específicas para determinar la persistencia temporal de ADN del hospedero en el contenido intestinal de Triatoma infestans que fueron alimentados experimentalmente con sangre de seis vertebrados muy frecuentemente asociados a enfermedad de Chagas: humano, perro, cobayo, pollo, ratón, y cerdo. Se emplearon 20 ninfas de tercer y cuarto estadio por cada especie de hospedero. Fueron alimentados a saciedad y mantenidas en el insectario sin alimentación posterior. Se obtuvo el contenido intestinal de cinco triatominos por cada grupo a los 7, 14, 21 y 28 días post - alimentación, que fueron evaluados con los respectivos PCRs específicos. El ADN de todos los vertebrados fue detectado en al menos 4 de 5 ninfas evaluadas a los 7 y 14 días post - alimentación. El ADN de humano, perro, cobayo, cerdo y pollo fue detectado exitosamente (80-100%) hasta el día 21 y con menos éxito (20-100%) en el día 28. Estos resultados demuestran que PCRs específicos para cada especie de hospedero pueden identificar consistentemente la fuente de alimentación de T. infestans dentro de las dos semanas post - alimentación, siendo un intervalo de tiempo biológicamente relevante.

Establishment of a molecular tool for blood meal identification in Malaysia

Objective: To establish a polymerase chain reaction (PCR) technique based on cytochrome b (cytb) gene of mitochondria DNA (mtDNA) for blood meal identification. Methods: The PCR technique was established based on published information and validated using blood sample of laboratory animals of which their whole gene sequences are available in GenBank. PCR was next performed to compile gene sequences of different species of wild rodents. The primers used were complementary to the conserved region of the cytb gene of vertebrate’s mtDNA. A total of 100 blood samples, both from laboratory animals and wild rodents were collected and analyzed. The obtained unknown sequences were compared with those in the GenBank database using BLAST program to identify the vertebrate animal species. Results: Gene sequences of 11 species of wild animals caught in 9 localities of Peninsular Malaysia were compiled using the established PCR. The animals involved were Rattus (rattus) tanezumi, Rattus tiomanicus, Leopoldamys sabanus,Tupaia glis, Tupaia minor, Niviventor cremoriventor, Rhinosciurus laticaudatus, Callosciurus caniseps, Sundamys muelleri, Rattus rajah and Maxomys whiteheadi. The BLAST results confirmed the host with exact or nearly exact matches (>89% identity). Ten new gene sequences have been deposited in GenBank database since September 2010. Conclusions: This study indicates that the PCR direct sequencing system using universal primer sets for vertebrate cytb gene is a promising technique for blood meal identification.

Elaboración de un concentrado de uso avícola a partir de residuos revalorizados de la industria alimentaria / Prodction of birrd feed concentrate from revalued residues of the food iduustry

La industria alimentaria genera residuos de contenido nutricional potencialmente utilizable. Sin embargo, los desechos producidos en los centros de sacrificio, por la carencia de posibilidades de aprovechamiento, se vierten al alcantarillado. No obstante, el hollejo generado en la industria procesadora de la papa se usa como abono. Por otra parte, el residuo cachaza de la industria panelera en La Paz (Santander) se convierte en el subproducto melote, con un contenido de carbohidratos de 3%. En este proyecto se revalorizaron tanto la sangre vacuna para obtener la harina de sangre que contiene proteína al 25% como el contenido ruminal que presenta el 3% de grasa y 2% de fibra. Este último se mezcló con melote y hollejo de papa que contiene 3% de fibra y 10% de proteína o con harina de sangre en proporción 3:3:4 para elaborar un subproducto revalorizado. La sangre vacuna se procesó a harina de sangre mediante deshidratación y cocción y el contenido ruminal se integró mediante fermentación anóxica con el melote y la harina (hollejo de papa) (relaciones 3:3:4/4:3:3). Este subproducto, denominado ruminasa, se ensayará como alimento para pollo criollo en un estudio que integra la agroindustria panelera, dos centros de sacrificio y una industria de papa. Los resultados ofrecerán una alternativa de trabajo para el personal de la industria cárnica, quienes quedarán cesantes cuando se cumpla la ley 1122 de 2007 y posibilitará la elaboración de un alimento para aves accesible técnica y económicamente a los campesinos de la región mediante el aprovechamiento de residuos regionales revalorizados.

The food industry produces waste with potentially useful nutritional content, but the debris produced in the slaughterhouses, due to the lack of ability to benefit from it, is discarded. However, the residues generated from the potato processing industry are used as fertilizer. Moreover, the sugarcane residue in La Paz (Santander) becomes treacle which has a carbohydrate content of 3%. This project revalued the cattle blood to obtain blood meal with a protein content of 25%, the ruminal content presents 3% fat and 2% fiber. The latter was mixed with treacle and potato skins containing 3% fiber and 10% protein or with blood meal to produce a 3:3:4 ratio revalorized subproduct. The cattle blood was processed into blood meal by means of dehydration and cooking; the rumen content was integrated by means of anoxic fermentation with treacle and flour (potato skin) (ratio 3:3:4 / 4:3:3). This subproduct, called ruminasa, will be tested as feed for creole chickens in a study that integrates the sugarcane agro-industry, two slaughterhouses and a potato industry. The results will offer a work alternative for the meat industry personnel who will become unemployed once the law 1122 of 2007 is applied. It will also allow the preparation of bird feed technically and economically accessible to farmers in the region by means of regional revalued residues.

Biotin/avidin sandwich enzyme-linked immunosorbent assay for Culicidae mosquito blood meal identification

The knowledge of mosquitoes Culicidae host feeding patterns is basic to understand the roles of different species and to indicate their importance in the epidemiology of arthropod-borne diseases. A laboratory assay was developed aiming at standardizing the biotin-avidin sandwich enzyme-linked immunosorbent assay, which was unprecedented for mosquito blood meal identification. The enzyme-linked immunosorbent assay (ELISA) activity was evaluated by the detection of titers on each sample of the 28 blood-fed Culex quinquefasciatus. In light of the high sensitivity that the technique permits, by means of small quantities of specific antibodies commercially provided and phosphatase substrate which reinforces additional dilutions, human and rat blood meals were readily identified in all laboratory-raised Culex quinquefasciatus tested. The assay was effective to detect human blood meal dilutions up to 1:4,096, which enables the technique to be applied in field studies. Additionally, the present results indicate a significant difference between the detection patterns recorded from human blood meal which corroborate the results of host feeding patterns.

Haematophagic behavior in laboratory of Lutzomyia cruzi (Mangabeira) (Diptera: Psychodidae) in relation to three mammalian blood sources in Manaus, Brazil

The sand fly Lutzomyia cruzi is considered as one of vectors of visceral leishmaniasis in Brazil. This work examined optimum feeding age, feeding time, host preference, fecundity rates, and female blood meal volume taken by single females from a closed colony of L. cruzi. Mean feeding time was longer on hamsters, 6.6 minutes, than on humans, 5.7 minutes. 49.1 percent of the 48h-old flies fed on humans and 43.3 percent of 72h-old flies fed on hamsters. Of a total of 120 females, 61 percent fed on humans and 25 percent fed on hamsters. Total fecundity was significantly higher in females fed on hamster than on human or opossum. Laboratory-reared L. cruzi females fed earlier, more promptly, and preferably on humans than on hamsters when offered these blood-meal sources simultaneously. The blood-meal volume is higher in females fed on hamsters than other hosts (human and opossum).

O flebotomíneo Lutzomyia cruzi é incriminado como um dos vetores de leishmaniose visceral no Brasil. Foram estudados: a idade ótima, a preferência alimentar, os índices de fecundidade e o volume de alimentação sanguínea realizado com fêmeas de L. cruzi colonizadas em laboratório. O tempo médio de alimentação foi maior em hamster, seguido de humano. Verificou-se que 49,1 por cento das fêmeas alimentaram-se em humano com 48h enquanto em hamster, 43,3 por cento alimentaram-se com 72h. Das 120 fêmeas observadas, 61 por cento realizaram a alimentação em humanos e 25 por cento em hamster. A fecundidade total foi maior nas fêmeas alimentadas em hamster, humano e mucura, respectivamente. Observou-se que fêmeas de L. cruzi colonizadas alimentam-se mais facilmente e preferencialmente em humanos do que em hamster quando ambas as fontes de alimentação são oferecidas simultaneamente. O volume da alimentação sanguínea foi maior nas fêmeas alimentadas em hamster.

STUDY ON CONDITIONS OF SWINE BLOOD MEAL FERMENTATION WITH COMPOUND STRAINS / 微生物学通报

Two high protease producing strains, whic h are desi gnated Aspergillus oryzae AS100 and AS102, were screened and applied as main fermentation strains of swine blood meal. A Saccharomyces cerevisiae Y113 and a Bacillus Asp007 were also used as assistant fermentation strains. The enzyme production abilities we re studied,and a series of parameters of the fermentation technology were deter mined. Through swine blood meal fermentation, a high-protein fermented feed wa s produced, which is strong soy flavor and was rich in protein(69%), free amino acid, vitamin such as VitD 3 and niacin and organic elements such as Fe. It is a kind of high-protein feed for animals and it could be used as feedstuff addi tive.

Variáveis relacionadas ao desenvolvimento de Triatoma infestans Klug, 1834 em condições de laboratório. 1. Relação entre o repasto sanguíneo e o desenvolvimento / Variables influencing the growth of Triatoma infestans Klug, 1834 in the laboratory: 1. Relation between blood meal and growth

Em continuação a estudos iniciados anteriormente, visando padronização de parâmetros envolvidos na realização de xenodiagnóstico, procurou-se observar neste experimento as relações existentes entre as manipulações em laboratório, a quantidade de sangue ingerido no repasto sanguíneo e o desenvolvimento ninfal de Triatoma infestans. Foram utilizados dois grupos, formados por 180 ninfas de 1.0 estádio cada um. Um destes grupos constituiu a amostra testada para as manipulações diárias de pesagem, enquanto o outro grupo foi mantido sem manipulação, servindo como controle. A manipulação interferiu na quantidade de sangue sugado, tendo o grupo manipulado sugado cerca de 35% menos sangue do que o controle. A quantidade de sangue sugado pelas ninfas, no estádio em que morreram, correspondeu a valor sensivelmente menor do que O observado para a média do volume de sangue sugado pelos demais insetos de mesmo estádio, que sobreviveram à muda seguinte. A medida que os reduvídeos avançaram em seus estádios evolutivos, necessitaram mais repastos; assim, no 1.0 estádio 82,43% das ninfas precisaram um único repasto, enquanto no 5.° estádio 77,39% tiveram que se alimentar duas ou mais vezes. Nos estádios mais jovens, quando ocorreu necessidade de mais de um repasto, dentro do mesmo estádio, observou-se que a quase totalidade das ninfas sugaram quantidade de sangue maior do que em repasto anterior. Tais informações permitem que os autores discutam sobre as formas e condições de criação de triatomíneos em laboratório e sobre as ninfas adequadas ao xenodiagnóstico (AU).