In an attempt to demonstrate the role of insects as possible carriers of pathogenic bacterial organisms this investigation has been concerned with the determination of the microbial population associated both internally and externally with the common house fly and three species of the cockroach.

In this thesis the expression pattern of five circadian clock genes (cwo, pdp 1{$\varepsilon$}, ck 1{$\varepsilon$}, ck 2{$\beta$} and pdh) was studied in the housefly (Musca domestica). The influence of temperature on the expression pattern of these five genes and of two others genes, per and tim, was examined. The locomotor activity of flies exposed to three different temperature conditions was studied.

Made available in DSpace on 2016-01-26T18:55:44Z (GMT). No. of bitstreams: 1 Dissertacao Leonice.pdf: 133859 bytes, checksum: f76fd4ea314f1866f9aa2bbb11079d19 (MD5) Previous issue date: 2008-04-23 / The study of Calliphoridae and Muscidae biodiversity in the garbage dump of Presidente Prudente, São Paulo, Brazil, was carried out between March, 2006 and March, 2007. To that purpose, six traps made of plastic bottles with 2 L capacity, and containing bovine liver as attractive, were placed around the garbage discarding site. The total of Calliphoridae captured was 44,688. Chrysomya megacephala was the most frequent species (93.61%; n= 41,833) of fly, with significant differences (p<0.05) between C. megacephala and C. albiceps (1.50%; n= 672) and C. putoria (0.79%; n= 352). There was influence of temperature and of rainfall on the C. megacephala population. In the coldest months, the capture of flies, especially C. albiceps e de C. putoria was extremely low. Regarding the Muscidae family, 1307 individuals were captured. Musca domestica was the most frequent species (99.6%; n= 1,302). The other 0.4% (n= 5) corresponded to Ophyra aenescens. The highest number of Muscidae was observed in the summer and in the springer. Thus, it is concluded that the garbage site of Presidente Prudente is an environment that gives conditions to maintenance of Calliphoridae and Muscidae, especially C. megacephala. / Estudou-se a biodiversidade de califorídeos e muscídeos no lixão de Presidente Prudente, São Paulo, Brasil, no período de março de 2006 a março de 2007. Para esse propósito, seis armadilhas com garrafas tipo pet de 2 litros, contendo como atrativo fígado bovino, foram alocadas ao redor do lixão. Foram capturadas 44.688 califorídeos, com maior freqüência das espécies Chrysomya megacephala (93,61%; n= 41.833), seguindo-se de C. albiceps (1,5%; n= 672) e C. putoria (0,79%; n= 352), com diferença significativa entre a primeira e as demais espécies (p<0,05). Houve influência da temperatura e da precipitação pluviométrica na sazonalidade de C. megacephala, com maiores capturas nos meses quentes e chuvosos (p<0,05). Nos meses frios, a captura das moscas, especialmente de C. albiceps e de C. putoria foi praticamente ausente. No caso dos muscídeos, capturou-se 1.307 espécimes, sendo que a espécie Musca domestica representou 99,6% (n= 1.302) e a espécie Ophyra aenescens 0,4% (n= 5), havendo maior incidência no verão, seguido da primavera, outono e inverno. Dessa forma, conclui-se que o depósito de lixo urbano de Presidente Prudente oferece condições para a manutenção de moscas varejeiras, especialmente C. megacephala, e de mosca doméstica.

Made available in DSpace on 2016-07-18T17:53:18Z (GMT). No. of bitstreams: 1 Dissertacao Leonice.pdf: 133859 bytes, checksum: f76fd4ea314f1866f9aa2bbb11079d19 (MD5) Previous issue date: 2008-04-23 / The study of Calliphoridae and Muscidae biodiversity in the garbage dump of Presidente Prudente, São Paulo, Brazil, was carried out between March, 2006 and March, 2007. To that purpose, six traps made of plastic bottles with 2 L capacity, and containing bovine liver as attractive, were placed around the garbage discarding site. The total of Calliphoridae captured was 44,688. Chrysomya megacephala was the most frequent species (93.61%; n= 41,833) of fly, with significant differences (p<0.05) between C. megacephala and C. albiceps (1.50%; n= 672) and C. putoria (0.79%; n= 352). There was influence of temperature and of rainfall on the C. megacephala population. In the coldest months, the capture of flies, especially C. albiceps e de C. putoria was extremely low. Regarding the Muscidae family, 1307 individuals were captured. Musca domestica was the most frequent species (99.6%; n= 1,302). The other 0.4% (n= 5) corresponded to Ophyra aenescens. The highest number of Muscidae was observed in the summer and in the springer. Thus, it is concluded that the garbage site of Presidente Prudente is an environment that gives conditions to maintenance of Calliphoridae and Muscidae, especially C. megacephala. / Estudou-se a biodiversidade de califorídeos e muscídeos no lixão de Presidente Prudente, São Paulo, Brasil, no período de março de 2006 a março de 2007. Para esse propósito, seis armadilhas com garrafas tipo pet de 2 litros, contendo como atrativo fígado bovino, foram alocadas ao redor do lixão. Foram capturadas 44.688 califorídeos, com maior freqüência das espécies Chrysomya megacephala (93,61%; n= 41.833), seguindo-se de C. albiceps (1,5%; n= 672) e C. putoria (0,79%; n= 352), com diferença significativa entre a primeira e as demais espécies (p<0,05). Houve influência da temperatura e da precipitação pluviométrica na sazonalidade de C. megacephala, com maiores capturas nos meses quentes e chuvosos (p<0,05). Nos meses frios, a captura das moscas, especialmente de C. albiceps e de C. putoria foi praticamente ausente. No caso dos muscídeos, capturou-se 1.307 espécimes, sendo que a espécie Musca domestica representou 99,6% (n= 1.302) e a espécie Ophyra aenescens 0,4% (n= 5), havendo maior incidência no verão, seguido da primavera, outono e inverno. Dessa forma, conclui-se que o depósito de lixo urbano de Presidente Prudente oferece condições para a manutenção de moscas varejeiras, especialmente C. megacephala, e de mosca doméstica.

The effect of protein in adult and larval diets for Ophyra aenescens (Wiedemann) (Diptera: Muscidae ), a facultative predator of the house fly, Musca domestica L., was examined. A larval diet of coarse wheat bran, vermiculite and dried meat powder was found adequate for rearing O. aenescens larvae. Protein content was important for maximum larval emergence and for F1 adult longevity and fecundity. Adult diet of powdered milk, sugar and dried meat powder was sufficient for maintenance of adult O. aenescens flies. Protein was needed in adult diet for optimal fecundity. Cyromazine was toxic to O. aenescens at high levels (1.0 ppm), but at 0.75 ppm O. aenescens tolerated cyromazine better than a susceptible strain of house flies. At these cyromazine levels, mass release of O. aenescens into poultry houses is possible one to two days after cyromazine has been removed from the chicken feed. The effect of temperature and manure moisture on O. aenescens was studied. At temperatures of 18°C, emergence of Ophyra aenescens was significantly lower than at temperatures of 21 and 27°C. Predation by O. aenescens at 27°C on house fly larvae was significant at ratios of 3:1, 2:1 and 1:1 (house fly to O. aenescens). A constant manure moisture was important in the development of O. aenescens larvae and its ability to prey on house fly larvae. At constant levels of 50, 60, and 70% manure moisture, O. aenescens substantially reduced house fly larval numbers at ratios of 3:1, 2:1 and 1:1. / Master of Science

Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011. / Includes bibliography. / ENGLISH ABSTRACT: The objective of this study was to evaluate the use of Musca domestica (common house fly) larvae meal, as protein source, for broiler production. This was done by investigating the nutritive value of house fly larvae meal together with its total tract digestibility, potential toxicity and carcass characteristics of the broilers supplemented with house fly larvae meal. The proximate analysis of house fly larvae meal show that it contained, on a dry matter basis, a gross energy value of 20.10 MJ/kg, 60.38% crude protein, 14.08% crude fat and 10.68% ash and that the house fly pupae contained a gross energy of 20.42 MJ/kg, 76.23% crude protein, 14.39% crude fat and 7.73% ash. House fly pupae meal had the closest match of amino acid profile when compared with the ideal amino acid profile required by broilers and it has arginine relative to the lysine content closer to the ideal amino acid profile than the house fly larvae meal. The essential fatty acid, linoleic acid, was found at levels of 26.25 and 36.27% of the total fats for the house fly larvae and pupae meal respectively. House fly larvae meal supplementation did not induce gizzard erosion or showed toxicity (regarding the gastro intestinal tract, immune system and organ stress) in broilers. Results revealed that house fly pupae meal had higher total tract digestibilities for most nutrients than of the house fly larvae meal. House fly larvae meal had a crude protein total tract digestibility of 69% and that of pupae meal was 79%. Both larvae and pupae meal had high amino acid total tract digestibilities of all the amino acids analysed. The house fly larvae and pupae meal had an apparent metabolizable energy (AME) value of 14.23MJ/kg and 15.15MJ/kg respectively. The larvae meal total tract crude fat and crude fibre digestibilities were 94% and 62% respectively. The pupae meal total tract crude fat and crude fibre digestibilities were 98% and 58% respectively. House fly larvae meal supplementation in a three phase feeding system significantly increased average broiler live weights at slaughter, total feed intake, cumulative feed intake as well as average daily gain (ADG) when compared to commercial maize: soya oil cake meal diet. In direct comparison of larvae inclusion levels with fishmeal in isonitrogenous and isoenergetic diet, no significant differences were observed between a 10% house fly larvae and a 10% fish meal diets regarding performance characteristic. The 25% house fly larvae meal diet yielded significantly better average broiler live weights at slaughter, total feed intake, cumulative feed intake (from the second week until slaughter) as well as average daily gain when compared to the 25% fish meal diet in the growth phases. Carcass characteristics of the 10% larvae, 10% fishmeal and commercial diets were compared. Chicks that received either the 10% house fly larvae meal or 10% fish meal supplementation produced significantly heavier carcasses and breast muscle portions than the chicks that received the commercial maize: soya oil cake meal. No treatment differences were found regarding breast and thigh muscle colour or pH. This study showed that house fly larvae meal can be regarded as a safe protein source that can be used to replace other protein sources and that has the ability to promote broiler performance without having any detrimental effects on carcass characteristics. / AFRIKAANSE OPSOMMING: Die doel van die studie was om die effek van Musca domestica (gewone huisvlieg) larwe meel, as ‘n protein bron, in braaikuikens te evalueer. Dit was gedoen deur die nutrient waarde van huisvlieg larwe meel saam met die totale spysvertering verteerbaarheid, moontlike toksiesiteit en karkas-eienskappe van braai kuikens te evalueer. Laboratoruim analiese toon dat huisvlieg larwe meel 20.10 MJ/kg bruto energie, 60.38% ru- protein, 14.08% ru- vet en 10.68% as bevat en huisvlieg papie meel 20.42 MJ/kg bruto energie, 76.23% ru- protein, 14.39% ru- vet en 7.73% as bevat. Huisvlieg papie meel stem die meeste ooreen met die idiale amino suur profiel soos wat benodig word deur braaikuikens en dit het ‘n arginien tot lisien verhouding wat die meeste ooreenstem met die idiale amino suur profiel in vergelyking met huis vlieg larwe meel. Die essensiele vet suur, linolien suur, was geanaliseer teen vlakke van 26.25- en 36.27% van die totale vette onderskeidelik vir huisvlieg larwe- en papie meel. Huisvlieg larwe meel vervanging het nie spiermaag erosie of enige ander toksiese effekte te veroorsaak nie. Resultate het getoon dat huisvlieg papie meel, in vergelyking met larwe meel, het ‘n hoër totale spysvertering verteerbaarheid vir meeste van die nutrient. Die huisvlieg larwe meel het ‘n totale ru- protein spysvertering verteerbaarheid van 69% en die van papie meel van 79%. Beide larwe en papie meel het hoë amino suur spysvertering verteerbaarheid. Larwe meel en papie meel het skynbare metaboliseerbare energie waardes van 14.23MJ/kg en 15.15%MJ/kg onderskeidelik. Die larwe meel het ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van 94% en 62% onderskeidelik, waar die papies ‘n ru-vet en ru- vesel spysvertering verteerbaarheid van onderskeidelik 98% en 58% het. Huisvlieg larwe meel vervanging in ‘n drie fase voer stelsel het getoon om die gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename te verhoog waneer dit vergelyk word met ‘n kommersiele mielie- soya olie koek dieet. Geen mekwaardige verskille was waargeneem toe die 10% larwe meel dieet direk met die 10% vismeel diet vergelyk was rakende enige produksie einskappe gemeet nie. Die 25% larwe meel dieet het merkwaardig beter gemiddelde braaikuiken lewende gewigte by slag, totale voer iname, sowel as die gemiddelde daaglikse toename getoon wanneer vergelyk word met die 25% vismeel dieet gedurende die verskeie groei fases. Karkas eienskappe van die 10% larwe meel, 10% vismeel en die kommersiele diete was gevergelyk. Kuikens wat 10% larwe meel en 10% vismeel in die diete ontvang het, het swaarder karkasse gelewer met swaarder borsie massas wanneer vergelyk word met die kommersiele mielie- soya olie koek dieet. Geen behandelings verskille was gevind rakende die borsie- en dy spier kleure of pH nie. Die studie toon dat huisvlieg larwe meel as ‘n veillige protein bron kan beskou word, wat gebruik kan word om ander protein bronne te vervang. Huisvlieg larwe meel het ook die vermoë om braaikuiken produksie te verhoog sonder om enige negitiewe effekte rakende die karkas eienskappe te toon nie.

House flies (Musca domestica L.) are common pests affecting horses and their owners. Control of house flies in stable yards is currently based on the use of pesticides. However, the development of resistance by these flies to most pesticide groups has motivated horse owners to seek alternative methods of fly control. An entomopathogenic fungus, Beauveria bassiana (Bb) and an entomopathogenic bacterium, Bacillus thuringiensis var. israelensis (Bti) are two biological agents known to have activity against house flies. The broad objective of this study was to evaluate the effect of these two biological control agents on house flies in an equine environment. Using a structured questionnaire, presented in Chapter 2, thirty horse owners in KwaZulu-Natal were asked about the nuisance value of house flies, their current control measures, the potential market for biocontrol agents against house flies, and each owner’s perception of biocontrol methods. The horse owners were using three methods of house fly control namely, physical, chemical and biological. Most horse owners (97%) wanted access to effective biocontrol agents for control of house flies. Most horse owners (80%) stabled their horses at night, some or all of the time. The resultant manure piles in the stable yard were considered to be the primary cause of house fly problems. About 64% of the horse owners were dissatisfied with the currently available methods of controlling house flies in this situation. Chapter 3 covers two observational trials in which varying doses of Bacillus thuringiensis var. israelensis (Bti) were fed to horses, in order to identify a baseline dosage to give to horses in order to adequately control house fly populations growing in horse manure. The bacterium Bti, grown on wheat bran, was fed to six miniature horses at doses of 0, 0.125, 0.25, 0.5, 0.75, and 1.0 g per meal in Trial 3a, and at 0, 0.5, 1, 2, 4 and 8 g per meal in Trial 3b. Faeces were collected three times a week for 11 weeks and placed in incubation trays to allow the number of emerging adult house flies and closed pupae to be counted. In Trial 3a, there was a significant reduction in the number of closed pupae with an increase in Bti in the feed. The regression equation suggests that there will be 3.1 times as many closed pupae in the faeces when horses are fed 1 g of Bti in their feed, than when horses are fed no Bti. This dosage is the minimum baseline dosage for future trials. v Using manure from horses dosed in Trials 3a and 3b, the survival of the bacterium through the gut of horses was evaluated using a standard isolation technique. The growth of Bt colonies on the manure after the Bt isolation technique showed that some of the bacterial cells survived transition through the digestive tract of the horse. This study was qualitative in nature and did not attempt to quantify the level of Bti spore survival. These two observations suggest that Bacillus thuringiensis var. israelensis has the potential to be used as a biocontrol agent, applied via horse feed, for the control of house flies in stable yards. Future clinical trials, with appropriate replication, should be conducted using 1 g Bti/meal as the lowest test dosage. The objective of Chapter 4 was to determine whether spraying Bti or Bb on to horse manure is effective in the control of house flies. Over a six week period, two spraying trials were conducted in which increasing doses of Bb and Bti were sprayed on to 500 g samples of horse manure. Counts of house fly pupae and adults were taken. The doses of Bb and Bti tested were 0, 1, 2, 4 g in Trial 4a, and 0, 4, 8 and 12 g in Trial 4b. The research reported in Chapter 4 was characterized by the unexpectedly high levels of biological variation in egg, larvae and pupae numbers that were found in samples of horse manure, taken from the same skip two days apart. The statistical design of the two trials conducted was inadequate to cope with the high level of variation about treatment means for fly and larval counts. However, despite the lack of significant differences between treatment means, there is observational evidence that suggests that both Bb and Bti do have an effect on house fly survival. A simplified statistical model, which compared the number of hatched house flies on untreated manure, with the number on manure treated with any level of Bb (1 to 4 g /250 ml water), found a significant reduction in the number of hatched flies on treated manure. There was no significant corresponding reduction in the number of closed pupae, which suggests that Bb acts primarily before the larva pupates. The optimal dose of Bb and Bti to be sprayed on to manure could not be determined because of the high variation about treatment means. It is suggested that, in future trials similar dosages for Bb could be tested, but that higher dosages of Bti (starting at 2 g/250 ml water) should be used. Trial periods should be extended and replication increased dramatically to reduce variation about treatment means. Transformation of data before analysis may also be necessary to equalize variation about treatment means. / M.Sc.Agric. University of KwaZulu-Natal, Pietermaritzburg 2013.

Research has been actively looking for alternative feed ingredients to reduce the reliance of the aquafeed industry on marine ingredients, namely fish meal (FM) and fish oil (FO). In this context, insects, in particular housefly (Musca domestica) and black soldier fly (BSF, Hermetia illucens) larvae, have been identified as promising candidates. Although a global insect farming industry is emerging, it is for now constrained by regulatory and technical bottlenecks that raise the question ‘where and how insect-based products could be integrated into aquaculture’. The literature indicated a high interspecies variability of the results when replacing FM with insect meals in fish diets and previous work failed to consider the existing challenges related to the insect production to demonstrate commercial relevance and applicability. In this thesis, maggot meals (MM) and frass (insect digestate) were assessed as strategic feed ingredients for two commercially important farmed species: Atlantic salmon, (Salmo salar) and Nile tilapia (Oreochromis niloticus), in their relevant contexts. Case studies showed that both housefly and BSF MM are high quality feed ingredients and suitable alternative to FM. Specifically, dietary inclusions of up to 200 g/kg of crude or defatted housefly larvae meal did not compromised the feed digestibility and utilisation and the growth performance and body composition of salmon parr (freshwater stage), compared to a FM-based control diet. Hormone (17α-methyltestosterone) treated diets containing between 250 and 1000 g/kg BSF or housefly meal were found as effective as a commonly used pure hormone-treated FM in sex-reversal process leading to 99.8 to 100% males, high survival and evenness of the fish produced. In a commercial diet for advanced nursing of Nile tilapia fingerlings, up to 80 g/kg BSF meal was included without impairing the fish performance and body composition; dietary inclusion was limited by the lipid content of the crude MM. Finally, BSF frass derived from brewery spent grains or processed food wastes were found more effective when used as soil bio-fertilisers with minimum application rate of 10.0 tonnes/ha or 5.0 tonnes/ha, respectively (for a spring onion culture), rather than supplemental feeds for tilapia farmed in semi-intensive conditions (fertilised pond). The study also indicated that site-specific conditions should be accounted to support appropriate and sustainable use of insect-based products but in any case, juvenile fish should be strategically targeted given their requirements. It is expected that this approach, could support the sustainable intensification of aquaculture and contribute more broadly to food security whilst contributing to the development of a circular economy.

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-02-01T11:42:20Z No. of bitstreams: 1 diegorodriguesmelo.pdf: 1192469 bytes, checksum: 7a17e7c77b3319206eae586410dc02e3 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-02-01T15:48:57Z (GMT) No. of bitstreams: 1 diegorodriguesmelo.pdf: 1192469 bytes, checksum: 7a17e7c77b3319206eae586410dc02e3 (MD5) / Made available in DSpace on 2016-02-01T15:48:57Z (GMT). No. of bitstreams: 1 diegorodriguesmelo.pdf: 1192469 bytes, checksum: 7a17e7c77b3319206eae586410dc02e3 (MD5) Previous issue date: 2014-02-18 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Objetivou-se avaliar a atividade inseticida do óleo essencial de Lippia sidoides e dos monoterpenos timol e carvacrol sobre larvas e pupas de Musca domestica através de testes de contato. Para a avaliação da mortalidade larval (ML) foram feitas observações 48h após o tratamento e acompanhamento das larvas sobreviventes até o estágio adulto, e estes índices foram incluídos na eficácia de tratamento larval (ETL). Para a eficácia de tratamento pupal (ETP), foram calculados a mortalidade pupal (MP) após seis dias do tratamento e o percentual de mal desenvolvimento dos adultos (PMD). Foram testadas oito concentrações do óleo essencial e das substâncias puras, variando de 0,625 até 30,0 mg/ml. A análise dos constituintes do óleo essencial mostrou o timol como seu componente majoritário (69,91%). As doses letais (DL50 e DL90) para larvas e pupas foram estimadas e o carvacrol apresentou os menores valores, seguido pelo timol e óleo de L. sidoides. Verificou-se ML de 100% a partir da concentração de 10,0 mg/ml para o carvacrol, 15,0 mg/ml para o óleo de L. sidoides e 30,0 mg/ml para o timol. Já para a ETL foi observada 100% de eficácia a partir da concentração de 5,0 mg/ml para o carvacrol e L. sidoides e 10,0 mg/ml para o timol. Com relação a MP, o óleo essencial de L. sidoides não apresentou atividade pupicida. Entretanto, para as concentrações de 20,0 e 30,0 mg/ml foi observado PMD, o que contribuiu para ETP de 44 e 46%, respectivamente. Já para o carvacrol a maior mortalidade foi alcançada na concentração de 20 mg/ml (58%) e para este terpeno não houve PMD. Para o timol observou-se maior MP (74%) para a concentração de 30,0 mg/ml com PMD de 60%, o que contribuiu para ETP de 84%. Os produtos testados apresentaram elevado potencial larvicida, o que os tornam promissores para o desenvolvimento de formulações ambientalmente seguras e não tóxicas para o controle de larvas de M. domestica e que, apesar de não terem sido totalmente efetivas no controle de pupas, seu uso para esse estágio pode ser indicado em um programa de Manejo Integrado de Pragas. / This study aimed to evaluate the insecticidal activity of the essential oil of Lippia sidoides and thymol and carvacrol monoterpenes against larvae and pupae of Musca domestica by contact tests. For the evaluation of larval mortality (LM) observations were made 48 hours after treatment and follow-up of surviving larvae to the adult stage, and these indices were included in the effectiveness of larval treatment (ELT). For the effectiveness of pupal treatment (EPT) were calculated pupal mortality (PM) after six days of treatment and the percentage of bad development of adults (PBD). Eight concentrations of the essential oil and pure substances, ranging from 0.625 to 30.0 mg/ml were tested. The analysis of the constituents of the essential oil thymol showed as its major component (69.91 %). The lethal dose (LD50 and LD90) for larvae and pupae were estimated and carvacrol showed the lowest values, followed by thymol and L. sidoides oil. It was found LM 100% at concentrations of 10.0 mg/ml for carvacrol, 15.0 mg/ml for L. sidoides oil and 30.0 mg/ml to thymol. As for the ELT 100% efficacy was observed starting at a concentration of 5.0 mg/ml for carvacrol and L. sidoides and 10.0 mg/ml to thymol. With respect to PM, the essential oil of L. sidoides showed no pupicida activity. However, for concentrations of 20.0 and 30.0 mg/ml was observed PBD, which contributed to EPT of 44 and 46%, respectively. As for carvacrol the highest mortality was achieved at a concentration of 20 mg/ml (58%) and to that terpene was not PBD. To thymol observed a higher PM (74%) for the concentration of 30.0 mg/ml with the PBD 60%, which contributed to 84% of EPT. The products tested showed high potential larvicide, which make them promising for the development of formulations environmentally safe and non-toxic for the control of larvae of M. domestica and that although they were not fully effective in the control pupae, their use for this stage can be indicated in a program of Integrated Pest Management.

The entomopathogenic fungus Beauveria bassiana and the bacterium Bacillus thuringiensis var. israelensis (Bti) have been widely studied for their role in biocontrol against many arthropods and extensively exploited for insect pest control. The purpose of this study was to evaluate the effect of four B. bassiana and two Bti formulations and their respective combinations, for the biological control of the common house fly, Musca domestica L., a major pest in poultry facilities. In vitro screening was undertaken to select the best B. bassiana isolates from 34 B. bassiana isolates and two Paecilomyces isolates. All the isolates of B. bassiana were found to be effective against adult house flies, but were marginally effective in controlling fly larvae. The Paecilomyces isolates were non-pathogenic towards both adult house flies and larvae. The best four isolates R444, 7320, 7569 and 7771 caused >90% mortality within 2d and were subjected to dose-mortality bioassays. Microscopic studies using light and scanning electron microscopy indicated the different durations of the lifecycle of B. bassiana development on the house fly. High temperature was found to delay conidial germination. Spore germination and mycelial growth were also inhibited by high adjuvant concentrations. Laboratory baseline bioassay data established, a dose-time response relationship using a waterdispersible granules (WDG) Bti formulation that demonstrated that the susceptibility of M. domestica larvae to a given concentration of Bti increased as the duration of exposure increased. In the laboratory studies, the LC50 and LC90 values of Bti for the larvae ranged between 65 - 77.4 and 185.1 - 225.9?g ml-1, respectively. LT50 and LT90 values were 5.5 and 10.3d respectively. In the field, a concentration of 10g Bti kg-1 (bran formulation) of feed resulted in 90% reduction of larvae for 4wk post-treatment. A higher concentration (2g L-1) of Bti in spray (WDG) applications was not significantly more effective than the lower concentration of 1g L-1. Thus, adding Bti to chicken feed has potential for the management and control of house flies in cagedpoultry facilities. The impact of oral feed applications of a bran formulation of Bti and a commercial chemical larvicide, Larvadex®, were compared with respect to their efficacy on the control of house fly 3 larval populations in poultry manure. The sublethal effects were manifested in terms of decreasing emergence of adult house flies. Although Larvadex® reduced larval density and caused significant reductions in emergence of adult house flies, it generally exhibited weaker lethal effects than Bti. The reduction levels achieved as a result of feeding 250mg Bti kg-1 at 5wk were similar to those achieved as a result of feeding twice the amount of Larvadex® at 4wk to the layers. From both an efficiency and economic perspective, comparisons to assess the impact of combining different concentrations of the two Bti formulations were carried out to evaluate their success in controlling house fly larvae and adults in poultry houses. The percentage mortality of larvae accomplished as a result of using a combination of 250mg kg-1 Bti in feed and 2g L-1 spray applications was equivalent to that obtained as a result of combining 500mg kg-1 Bti in feed and 1g L-1 spray application. The cost-benefit analysis (expressed in terms of mortality of larvae) indicated that the most effective combination for control of house fly larvae and fly emergence was the 500mg kg-1 in feed and 2g L-1 spray application combination that resulted in 67% larval mortality and 74% inhibition of adult house fly emergence. This study presents commercial users with possible combinations of applications of the two Bti formulations. Comparisons of larval mortalities and house fly emergence resulting from the Bti - B. bassiana treatments with those from Larvadex® - B. bassiana treatments, showed better control levels compared to any of the individual agents alone. The Bti treatments were more effective at controlling larval populations and inhibiting the emergence of house flies than Larvadex®, even when Larvadex® was applied together with B. bassiana. The effects of the Bti - B. bassiana and the Larvadex® - B. bassiana interactions were additive. These trials suggest that the efficacy of Bti in the control of house fly larvae may be improved with frequent applications of B. bassiana. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.