Effects of replacing fishmeal with black soldier fly larval meal in the diets of grower-finishing guinea fowls reared under tropical conditions

The study was conducted with the view to determine the impact of replacing fishmeal with black soldier fly larval meal (BSFLM) on growing guinea fowls. BSFLM replaced fishmeal (3% in the control diet) in the ratios of 0, 20, 40, 60, 80, and 100% to produce six dietary treatments, which were iso-caloric and iso-nitrogenous. Two hundred and forty-eight-week old guinea fowls with mean live weight of 273.2 ± 10.9 g were tagged, weighted, and randomly assigned to 24 (6 × 4) floor pens; each pen was treated as a replicate. Feed and water were provided ad libitum during the entire period, which lasted 10 weeks. Feed consumption differed among the treatment groups (P = 0.0072) with the 100% fishmeal diets recording the lowest. Daily gain was significantly (P = 0.009) higher for birds fed high BSFLM diets compared to the control (100% fishmeal diet). The inclusion of BSFLM in the diets elicited positive linear effect on weight gains of the guinea fowls (R2 = 0.91) with increasing concentration resulting in higher live weight gains. The feed conversion ratio (FCR) also differed between treatments (P < 0.05) but similar for the 100% fishmeal (control) and 100% BSFLM diets. Organ and haematopoitic integrity were equally assured regardless of levels of the protein sources fed to the birds. Generally, meats from birds fed 60 to 100% BSFLM and from hens were more acceptable. A study to evaluate the economics of utilising BSFLM in guinea fowl production is recommended

From waste to feed: the Black Soldier fly (Hermetia illucens) as a novel feed source for monosex tilapia (Oreochromis niloticus)

The aquafeed industry is highly dependent on fishmeal (FM) and high-protein plant substitutes. Rising costs and sustainability concerns are fueling the search for novel alternatives. Black Soldier Fly (BSF) larvae (Hermetia illucens) have been demonstrated to be a potential new source of sustainable protein. While they can be grown on a wide range of waste-substrates, have a short life-cycle, and a favourable nutritional profile, they can be seen as a credible candidate. In this thesis, we focused on the selection of a potential substrate in a local context, and the type of larval stage to harvest in order to optimise both production and quality of the maggot meal (MM). From these preliminary studies fruit waste were selected to grow the larvae, harvested at the “white larvae” stage to produce the MM. As the availability of MM is yet –far- from being sufficient to cover the ever-growing demand for aquafeed, a strategic use was decided in contextualised and commercially-relevant researches. In large-scale tilapia farm, all-male production is desired to optimise the production as they grow bigger and faster than females. To do so 17α-methyltestosterone is added to the feed during the first 21 days of the fry. To maximize the ingestion, low quantities but high quality feed are required. In this context, the MM was used as a feed-hormone carrier for tilapia fry (Oreochromis niloticus) in two experiments. Whereby the first was based on simple substitution of fish meal (FM) and commercial feed with MM (Chapter 5), the second compared 12 isoenergetic and isoproteic formulated feeds based on a prior MM digestibility analysis (Chapter 6). Results indicated that different dietary inclusions of MM did not significantly affect sex reversal rates nor fish production performance, suggesting that MM offers potential as a locally sourced feed ingredient for tilapia hatchery. This strategic application is further enhanced by the potential to co-located MM and fry-production offering producers’ greater ability to manage quality assurance

A review of Capezoum Adlbauer, 2003 (Coleoptera: Cerambycidae) with the description of two new species from the Succulent Karoo ecosystem in South- Africa

Maquart, Pierre-Olivier, Vitali, Francesco, Bate, Riana (2021): A review of Capezoum Adlbauer, 2003 (Coleoptera: Cerambycidae) with the description of two new species from the Succulent Karoo ecosystem in South- Africa. Zootaxa 4915 (4): 559-566, DOI: https://doi.org/10.11646/zootaxa.4915.4.

Description of two new Obriini Mulsant, 1839 (Coleoptera: Cerambycidae) from the Tankwa Karoo biome in South Africa and Namibia

Maquart, Pierre-Olivier, Richard, Denis, Vitali, Francesco (2018): Description of two new Obriini Mulsant, 1839 (Coleoptera: Cerambycidae) from the Tankwa Karoo biome in South Africa and Namibia. Zootaxa 4521 (2): 183-190, DOI: https://doi.org/10.11646/zootaxa.4521.2.

Mosquito Vector Competence for Japanese Encephalitis Virus

International audienceJapanese encephalitis virus (JEV) is a zoonotic pathogen mainly found in East and Southeast Asia and transmitted by mosquitoes. The objective of this review is to summarize the knowledge on the diversity of JEV mosquito vector species. Therefore, we systematically analyzed reports of JEV found in field-caught mosquitoes as well as experimental vector competence studies. Based on the investigated publications, we classified 14 species as confirmed vectors for JEV due to their documented experimental vector competence and evidence of JEV found in wild mosquitoes. Additionally, we identified 11 mosquito species, belonging to five genera, with an experimentally confirmed vector competence for JEV but lacking evidence on their JEV transmission capacity from field-caught mosquitoes. Our study highlights the diversity of confirmed and potential JEV vector species. We also emphasize the variety in the study design of vector competence investigations. To account for the diversity of the vector species and regional circumstances, JEV vector competence should be studied in the local context, using local mosquitoes with local virus strains under local climate conditions to achieve reliable data. In addition, harmonization of the design of vector competence experiments would lead to better comparable data, informing vector and disease control measures

Mosquito diversity (Diptera: Culicidae) and medical importance in four Cambodian forests

International audienceBackgroundA total of 290 mosquito species are recorded in Cambodia among which 43 are known vectors of pathogens. As Cambodia is heavily affected by deforestation, a potential change in the dynamic of vector-borne diseases (VDBs) could occur through alteration of the diversity and density of sylvatic vector mosquitoes and induce an increase in their interactions with humans. Understanding mosquito diversity is therefore critical, providing valuable data for risk assessments concerning the (re)emergence of local VBDs. Consequently, this study mainly aimed to understand the spatial and temporal distribution of sylvatic mosquito populations of Cambodia by determining which factors impact on their relative abundance and presence.MethodsA study was conducted in 12 sites from four forests in Cambodia. All mosquitoes, collected during the dry and rainy seasons, were morphologically identified. The diversity and relative density of mosquito species in each site were calculated along with the influence of meteorological and geographical factors using a quasi-Poisson generalized linear model.ResultsA total of 9392 mosquitoes were collected belonging to 13 genera and 85 species. The most represented genera were Culex, accounting for 46% of collected mosquitoes, and Aedes (42%). Besides being the most abundant species, Culex pseudovishnui and Aedes albopictus, which are known vectors of numerous arboviruses, were present in all sites during both dry and rainy seasons. The presence of mosquito species reported to be zoo-anthropophilic feeders was also observed in both forested and urban areas. Finally, this study demonstrated that altitude, temperature and precipitation impacted the abundance of mosquitoes but also influenced species community composition.ConclusionThe results indicate an important diversity of mosquitoes in the four forests and an influence of meteorological and geographical factors on their community. Additionally, this work highlights in parallel the abundance of species considered to be of medical importance and therefore underlines the high risk of pathogen emergence/re-emergence in the region

Variations in the carapace shape of whip spiders (Arachnida: Amblypygi).

12 pagesInternational audienceMorphological studies often need to reference body size to correctly characterise the shape of organisms. In arthropods, the most commonly used reference for this is the length or width of the carapace, thorax, or the prosoma in the case of chelicerates. However, in the case of animals with unlimited growth, such as whip spiders, this measure could be irrelevant if growth is allometric. In this study, we analyse the ontogenetic modifications in prosoma outline shape in whip spiders during growth and compare the differences in shape between species. Differences are important for the relative prosoma width between species and, in the case of Damon medius, during growth in the juvenile stages, whereas the shape remains stable in mature stages. We conclude that a one-dimensional measure (i.e., length or width) suffices for mature specimens of a single species or family, but for larger studies, or when including immature specimens, at least the prosoma area (within the outline shape) should be used as a size estimator

Checklist of the mosquito fauna (Diptera, Culicidae) of Cambodia

Between 2016 and 2020, the Medical and Veterinary Entomology unit of the Institut Pasteur du Cambodge collected over 230,000 mosquitoes. Based on this sampling effort, a checklist of 290 mosquito species in Cambodia is presented. This is the first attempt to list the Culicidae fauna of the country. We report 49 species for the first time in Cambodia. The 290 species belong to 20 genera: Aedeomyia (1 sp.), Aedes (55 spp.), Anopheles (53 spp.), Armigeres (26 spp.), Coquillettidia (3 spp.), Culex (57 spp.), Culiseta (1 sp.), Ficalbia (1 sp.), Heizmannia (10 spp.), Hodgesia (3 spp.), Lutzia (3 spp.), Malaya (2 spp.), Mansonia (5 spp.), Mimomyia (7 spp.), Orthopodomyia (3 spp.), Topomyia (4 spp.), Toxorhynchites (4 spp.), Tripteroides (6 spp.), Uranotaenia (27 spp.), and Verrallina (19 spp.). The Cambodian Culicidae fauna is discussed in its Southeast Asian context. Forty-three species are reported to be of medical importance, and are involved in the transmission of pathogens

Host-Feeding Preference and Diel Activity of Mosquito Vectors of the Japanese Encephalitis Virus in Rural Cambodia

International audienceJapanese Encephalitis (JE) is the most important cause of human encephalitis in Southeast Asia, and this zoonosis is mainly transmitted from pigs to human by mosquitoes. A better understanding of the host-feeding preference of Japanese encephalitis virus (JEV) major vectors is crucial for identifying risk areas, defining bridge vector species and targeting adapted vector control strategies. To assess host-feeding preference of JE vectors in a rural Cambodian area where JE is known to circulate, in 2017, we implemented four sessions of mosquito trapping (March, June, September, December), during five consecutive nights, collecting four times a night (6 p.m. to 6 a.m.), and using five baited traps simultaneously, i.e., cow, chicken, pig, human, and a blank one for control. In addition, blood meals of 157 engorged females trapped at the same location were opportunistically analyzed with polymerase chain reaction (PCR), using cow, pig, human, and dog blood primers. More than 95% of the 36,709 trapped mosquitoes were potential JE vectors. These vectors were trapped in large numbers throughout the year, including during the dry season, and from 6 p.m. to 6 a.m. Despite the apparent host-feeding preference of Culex vishnui, Cx. gelidus, and Cx. tritaenhyorhincus for cows, statistical analysis suggested that the primary target of these three mosquito species were pigs. Dog blood was detected in eight mosquitoes of the 157 tested, showing that mosquitoes also bite dogs, and suggesting that dogs may be used as proxy of the risk for human to get infected by JE virus