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Tsetse flies (Diptera: Glossinidae) are the cyclical vectors of human (HAT) and animal (AAT) trypanosomiasis in sub-Saharan Africa, which constitutes a major constraint for human and animal health. Tsetse populations can be reduced using a variety of techniques. This studies aimed to validate the use of adhesive film as a measurement tool for riverine tsetse flies. For this study, two targets have been used. 1mx1m targets and small 0.25mx0.25m targets with adhesive film were compared using electrocuting sampling methods. Four treatments were compared for 12 days in a 4x4 latin square at Folonzo and Solenzo. Our results showed that the large targets (1mx1m black/blue/black BlkBBlk)) (film or grid) captured significantly more G. tachinoides and G. p. gambiensis than the reduced targets (0.25mx0.25m BlkBBlk) (p ≤0, 001) ..For the large targets (1mx1m) G. tachinoides was significantly attracted on target covered adhesive film (27.91 flies/day) compared to the electric grid (19.65flies/day); p ≤0, 1. The effect of adhesive film on color show also that the blue color of the 1mx1m BlkBBlk film was significantly more attractive than the target (1mx1m BlkBBlk) in the grid for G. tachinoides. No difference was observed between the targets with film and grid for the two colors (blue and black) for G. p. gambiensis in Folonzo and Solenzo. We conclude that adhesive film could be used as a strategic control tool against African Trypanosomiasis vectors.&nbsp

Additional file 1: Figure S1. Map (study area) of the origins of Djallonk�� sheep sub-populations.

Phenotypic characterization is used to identify and document diversity within and between distinct breeds, based on their observable attributes. Study to assess the body characteristics and variability of 204 Djallonke (West African dwarf) ewes was conducted in three agro-ecological zones (central, western and northern) of Cote d’Ivoire, from November 2016 to April 2017. Animals were described using visual appreciation of the body hair coat (colour type and pattern), hair length, ear orientation, tail type and the facial (head) profile. The linear body measurements, such as ear and tail length, muzzle length and width, height at wither, chest depth, and chest girth were also described. The data collected were subjected to principal component (PCA) and discriminant analysis. Results showed that the most common Djallonke ewes had erected ear (87.25%), thin tail and straight face. The dominant colour pattern of the body hair coat was patchy (64.22%) followed by plain (32.84%) and spotted (2.94%). The agro-ecological zone had a significant (pE‚0.01) effect on some linear body measurements (muzzle length, ear length and height wither). Based on PCA performed with all the above morphological variabilities, we were able to segregate the Djallonke ewes’ into three clusters (I, II and III). Discriminant analysis revealed that 76.27% sheep of cluster I, 92.80% sheep of cluster II and 90% sheep of cluster III were correctly classified in their original cluster. This result indicated that Ivorian Djallonke sheep population comprises of three well characterized morphological types of animals. This information could constitute a basis for further characterization and development of conservation strategies for Djallonke sheep breeding in Cote d’Ivoire. Key words: Local, sheep, breed, morphological, variability, West Africa.

Local breeds of Sahelian small-ruminant (SR) in Senegal are highly adapted to extensive farming systems despite feeding and health constraints, especially in a climate change context. As an important source of protein for populations, SR also generate substantial income. Despite this importance, their productivity in rural farming systems is rarely studied. The main objective of this study is to analyze demographic dynamics of SR’s flocks in the Ferlo zone using last twelve months retrospective surveys. The surveys were carried out on 52 flocks belonging to 32 rural households. With a predominance of adult females, a total number of 604 sheep and 450 goats are counted with an average size of 19.48 ± 9.63 and 21.43 ± 11.35 heads per flock respectively for sheep and goat. The annual birth rate was 84.1 ± 5.4 for goats and 85.5 ± 5.3% for sheep. Young animals were particularly affected by mortality with a frequency of 16.8 ± 3.0 and 13.2 ± 3.0% respectively for sheep and goats. Purchase was the main reason for entrance of animals into the flocks. For animal exits, mortalities were the main reason for sheep whereas for goats, sales were the main reasons. The global offtake rate was 23.8 ± 2.1% for sheep and 26.8 ± 2.5% for goats and adult males were mostly concerned. Despite low productivity, SR breeding remains an important economic activity for the rural populations. Les races locales de petits ruminants (PR) saheliens du Senegal sont tres adaptees a l’elevage extensif malgre les contraintes alimentaires et sanitaires surtout dans le contexte actuel de changement climatique. Importante source de proteines pour les populations, les PR leur generent aussi des revenus substantiels. En depit de cette importance socio- economique, peu d’etudes ont porte sur les performances et la gestion des animaux dans leur environnement d’elevage. L’objectif de ce travail est d’etudier la dynamique des troupeaux de PR dans la zone semi-aride du Ferlo. Ainsi, des enquetes retrospectives transversales par la methode des 12 derniers mois ont ete realisees dans 52 troupeaux ruraux durant le mois d‘avril 2017. Sur l’ensemble des troupeaux enquetes 604 ovins et 450 caprins ont ete enregistres avec des tailles moyennes de 19,48±9,63 et 21,43±11,35 tetes par troupeau respectivement pour les ovins et les caprins. Le taux de mises-bas annuel est de 84,1 ± 5,4% pour les chevres et 85,5 ± 5,3% pour les brebis. La mortalite a particulierement touche les jeunes animaux avec des frequences respectives de 16,8 ± 3,0 et 13,2 ± 3,0% pour les ovins et les caprins. L’achat a ete le principal motif d’entree d’animaux dans les exploitations tandis que la mortalite et la vente ont constitue les principaux motifs de sortie respectivement pour les ovins et les caprins. Le taux d’exploitation de 23,8 ± 2,1% pour les ovins contre 26,8 ± 2,5% pour les caprins et les mâles adultes sont principalement les plus exploites. Les contraintes et constats identifies dans cette etude doivent etre pris en compte pour le developpement des filieres ovine et caprine dans la zone semi-aride du Senegal.

International audience; The helmeted guinea fowl Numida meleagris belongs to the order Galliformes. Its natural range includes a large part of sub-Saharan Africa, from Senegal to Eritrea and from Chad to South Africa. Archaeozoological and artistic evidence suggest domestication of this species may have occurred about 2,000 years BP in Mali and Sudan primarily as a food resource, although villagers also benefit from its capacity to give loud alarm calls in case of danger, of its ability to consume parasites such as ticks and to hunt snakes, thus suggesting its domestication may have resulted from a commensal association process. Today, it is still farmed in Africa, mainly as a traditional village poultry, and is also bred more intensively in other countries, mainly France and Italy. The lack of available molecular genetic markers has limited the genetic studies conducted to date on guinea fowl. We present here a first-generation whole-genome sequence draft assembly used as a reference for a study by a Pool-seq approach of wild and domestic populations from Europe and Africa. We show that the domestic populations share a higher genetic similarity between each other than they do to wild populations living in the same geographical area. Several genomic regions showing selection signatures putatively related to domestication or importation to Europe were detected, containing candidate genes, most notably EDNRB2, possibly explaining losses in plumage coloration phenotypes in domesticated populations.

National audience; Animal African Trypanosomosis (AAT) is a vector-borne disease caused by blood protozoan parasites of the Trypanosoma genus. It represents a major constraint to the development of cattle breeding in the humid and sub-humid zones of Africa because of the high morbidity and mortality it causes. Zebu breeds and European taurine breeds are very susceptible to AAT and they usually die in the absence treatment. On the contrary, some taurine breeds in West Africa have the capacity to tolerate the disease and are called trypanotolerant. The trypanotolerant phenotype is known to be polygenic and multifactorial, but up to now, its mechanisms remain unknown. In order to decipher the molecular bases of trypanotolerance, we chose to analyse the genes expression of blood cells of susceptible and tolerant cattle during an experimental infection, performed in Burkina Faso, in 40 cattle from five West African breeds with T. congolense. mRNA were extracted from blood, comprising bovine leukocytes and parasites, before and during the infection and were sequenced using a Illumina highSeq2000. We mapped the reads on the bovine and trypanosome genomes, counted the reads on the annotated genes and performed a differential expression analysis. The genes identified as differentially expressed during the infection were then analysed using the Ingenuity Pathway Analysis software in order to identify enriched functional patterns. The functional analyses highlighted upstream regulators and canonical pathways associated with the immune response, the cell proliferation and signaling. Very fine differences in the modulation of the response between trypanotolerant and susceptible cattle were observed.

The genetic characteristics of cattle breeds of Benin are little known. This study aimed to assess the genetic diversity of major cattle breeds of Benin. For this purpose, blood samples from 179 cattle including 31 Girolando, 30 White Fulani cattle, 31 Borgou, 31 Lagunaire, 43 Somba and 13 crossbreed Azawak x Lagunaire were characterized using 12 microsatellites markers. All used microsatellites were polymorphic within each breed of cattle. The TGLA53 marker presented the highest number of alleles (15) in the Borgou cattle while the lowest number of alleles (2) was found at the INRA 63 locus for crossbreed Azawak x Lagunaire. The observed heterozygosity rates ranged from 0.79 to 0.57 in Girolando and Somba populations respectively. The highest expected heterozygosity rates were observed in the Girolando cattle population (0.79) while the the lowest (0.63) was encountered in Lagunaire and Somba populations. The lowest value of the differentiation indice between population pairs (0.084) was observed between Borgou and White Fulani cattle. Genetic structure analysis clustered Somba and Lagunaire cattle breeds while White Fulani and Borgou cattle breeds were very close. The crossbreed populations (Borgou and Azawak x Lagunaire) were between taurine and zebu. However, taurine were introgressed (20% on average) by the zebu blood. This study is a basic information in undertaking a conservation program and/or for support in the elaboration of a genetic improvement program for local cattle breeds of Benin.

National audience

Information on morphological characteristics is a prerequisite to sustainable breed improvement, utilization, and conservation. In this study, 108 N’Dama cattle cows from 11 farms of central and northwestern regions of Côte d’Ivoire were described using visual appreciation criteria and linear body measurements. The variables were studied using principal component analysis (PCA) and discriminant analysis. Results indicated that the most common N’Dama is fauve (83.33%) and it has straight back profile (69.44%) and lyre horn (74.07%). Agroecological zone has a significant (p˂0.01) effect on linear body measurements of N’Dama. The central region animals had higher head width (18.94 ± 2.18 cm), skull length (22.51 ± 2.18 cm), skull width (16.51 ± 1.72 cm), muzzle circumference (40.83 ± 2.58 cm), distance between horns (15 ± 1.90 cm), ear length (17.46 ± 2.57 cm), chest length (160.11 ± 15.8 cm), chest depth (71.55 ± 7.41 cm), and body length (125.13 ± 12.22cm) than those of northwestern region N’Dama. Thus, their respective values were: 15.41 ± 2.85 cm, 18.62 ± 2.6 cm, 12.44 ± 3.94 cm, 38.8 ± 2.61 cm, 13.72 ± 1.52 cm, 16.41 ± 1.61 cm, 143.84 ± 8.35 cm, 65.25 ± 4.1 cm, and 119.18 ± 12.38 cm. PCA revealed that N’Dama morphometric variability performed from the 9 variables (Lt, lt, Lc, lc, pt, hg, Pth, Lcp and Lf) were more associated with the first two factors. In regards to the discriminant analysis, these 9 variables distinguished the N’Dama significantly (p˂0.05) into two populations that corresponds with the two agroecological zones.

Q fever is a highly infectious disease with a worldwide distribution. Its causative agent, the intracellular bacterium Coxiella burnetii, infects a variety of vertebrate species, including humans. Its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. A few tick species were recently found to harbor maternally-inherited Coxiella-like organisms engaged in symbiotic interactions, but their relationships to the Q fever pathogen remain unclear. Here, we extensively sampled ticks, identifying new and atypical Coxiella strains from 40 of 58 examined species, and used this data to infer the evolutionary processes leading to the emergence of C. burnetii. Phylogenetic analyses of multi-locus typing and whole-genome sequencing data revealed that Coxiella-like organisms represent an ancient and monophyletic group allied to ticks. Remarkably, all known C. burnetii strains originate within this group and are the descendants of a Coxiella-like progenitor hosted by ticks. Using both colony-reared and field-collected gravid females, we further establish the presence of highly efficient maternal transmission of these Coxiella-like organisms in four examined tick species, a pattern coherent with an endosymbiotic lifestyle. Our laboratory culture assays also showed that these Coxiella-like organisms were not amenable to culture in the vertebrate cell environment, suggesting different metabolic requirements compared to C. burnetii. Altogether, this corpus of data demonstrates that C. burnetii recently evolved from an inherited symbiont of ticks which succeeded in infecting vertebrate cells, likely by the acquisition of novel virulence factors.

Q fever is a highly infectious disease with a worldwide distribution. Its causative agent, the intracellular bacterium Coxiella burnetii, infects a variety of vertebrate species, including humans. Its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. A few tick species were recently found to harbor maternally-inherited Coxiella-like organisms engaged in symbiotic interactions, but their relationships to the Q fever pathogen remain unclear. Here, we extensively sampled ticks, identifying new and atypical Coxiella strains from 40 of 58 examined species, and used this data to infer the evolutionary processes leading to the emergence of C. burnetii. Phylogenetic analyses of multi-locus typing and whole-genome sequencing data revealed that Coxiella-like organisms represent an ancient and monophyletic group allied to ticks. Remarkably, all known C. burnetii strains originate within this group and are the descendants of a Coxiella-like progenitor hosted by ticks. Using both colony-reared and field-collected gravid females, we further establish the presence of highly efficient maternal transmission of these Coxiella-like organisms in four examined tick species, a pattern coherent with an endosymbiotic lifestyle. Our laboratory culture assays also showed that these Coxiella-like organisms were not amenable to culture in the vertebrate cell environment, suggesting different metabolic requirements compared to C. burnetii. Altogether, this corpus of data demonstrates that C. burnetii recently evolved from an inherited symbiont of ticks which succeeded in infecting vertebrate cells, likely by the acquisition of novel virulence factors., Author Summary How virulent infectious diseases emerge from non-pathogenic organisms is a challenging question. Here, we address this evolutionary issue in the case of Q fever. Its causative agent, the intracellular bacterium Coxiella burnetii, is extremely infectious to humans and a variety of animals. However, uncertainty persists regarding its evolutionary origin, including the identity and lifestyle of its ancestors. In this article, we show that C. burnetii arose from a rare evolutionary transformation of a maternally-inherited endosymbiont of ticks into a specialized and virulent pathogen of vertebrates. While arthropod symbionts are typically transmitted maternally and thought not to be infectious to vertebrates, we establish here that one Coxiella symbiont has evolved the necessary adaptations to exploit the vertebrate cell, leading to the emergence of Q fever.

Background Continued post-elimination monitoring is required to ensure sustainability of zero transmission of human African trypanosomosis (HAT) and to avoid re-emergence caused by potential remaining Trypanosoma brucei gambiense reservoirs (animal and/or human). Until now, no tool is able to attest or validate elimination. Increasingly, the serological immune trypanolysis test is being implemented in the decision algorithms to characterise parasitological unconfirmed CATT or RDT seropositive subjects. Therefore, we wanted to assess further the high specificity of immune trypanolysis. Methods We first tested samples from domestic animals from a tsetse-infested area in Ethiopia, a country where no T. b. gambiense exists, but where bovine trypanosomosis is prevalent. Then, we tested cattle and human samples from the south-west of Burkina Faso, a historical focus of gambiense HAT that still shelters tsetse flies populations and animal trypanosomosis. Lastly, we were interested in testing human samples from active foci in Cote d9Ivoire and Guinea. Results Our results showed zero trypanolysis-positive animals from Ethiopia while in the historical HAT foci in Burkina Faso, 4.89% (14/286) of cattle were trypanolysis-positive. In humans, zero samples over 729 were trypanolysis-positive in Burkina Faso, while the percentage of positives was 3.77% (44/1166) in Guinea, including 7 new cases diagnosed during the sampling and 1.3% in Cote d9Ivoire (8/598). Conclusions Considering results from this study, we think that trypanolysis test, confirmed to be a very specific test in human, can be a tool able to certify HAT elimination in a given area. It also suggests that the risk of the reintroduction of T. b. gambiense in Burkina Faso is real, especially in the south-west which shelters a high density of tsetse populations, in addition to the possible presence of T. b. gambiens e in domestic animals. However, further studies on the specificity of the trypanolysis test regarding T. b. gambiense in animals should be conducted.