Anti-Trypanosomal Activity of Guiera senegalensis on Trypanosoma brucei Infected Mice

Aqueous decoction of Guiera senegalensis leaves was studied orally and intraperitoneally for its antitrypanosomal activity on mice infected experimentally with Trypanosoma brucei brucei. After a phytochemical screening followed by an acute toxicity study on mice, the extract of plant was administered once daily for 2 days at doses of 60, 120 and 240 mg / kg orally and 15, 30 and 60 mg / kg intraperitoneally after infection. Then, parameters of parasitaemia, packed cell volume (PCV), mean survival time and body weight of the mice treated with the extract were measured and compared with positive (diminazene aceturate) and negative (distilled water) controls for 7 days in a row. Results indicate that the aqueous extract of G. senegalensis leaves contains tannins, flavonoids, saponosides, reducing compounds and anthocyanosides, alkaloids and coumarins. LD50 of the extract are 1264.49 mg / kg by oral route and 316.22 mg / kg by intraperitoneal route. The doses of 240 mg / kg by oral route and 15 and 60 mg / kg by intraperitoneal route of aqueous extract showed a mean survival time (5 days) comparable to the positive control. Parasitaemia level increased in all mice tested except in mice treated with diminazene aceturate during the post-infestation period. During this period, PCV and body weight of all mice decreased by both routes of administration. These results of the study show the pharmacological utility of G. senegalensis leaves in the control of TAA by herders / pastoralists and suggest continuing further bio-guided studies to isolate the active components of the plant in order to improve their efficiency. Keywords: In vivo test; Trypanosoma brucei brucei; Guiera senegalensis leaves; phytochemical screening; acute toxicity

Impact des Déchets Plastiques sur les Pâturages Urbains et Péri-urbains de la Ville de Dori, Région du Sahel : cas des Ruminants Domestiques

Les pâturages naturels constituent la principale ressource alimentaire des ruminants dans la zone urbaine et péri-urbaine de Dori. Ces pâturages naturels sont non seulement insuffisants pour les animaux mais aussi pollués par les sachets plastiques. Cette insuffisance alimentaire (quantitative et qualitative) amène les ruminants à ingérer des sachets plastiques. Notre étude avait pour objectif général d’étudier la prévalence de l’ingestion des sachets plastiques chez les ruminants (bovins, caprins et ovins). Elle s’est déroulée de février à juin 2021 par une collecte aléatoire de données à l’abattoir sur 600 échantillons de ruminants domestiques : 200 bovins, 200 caprins et 200 ovins. Nos résultats ont révélé que la prévalence de l’ingestion des sachets n’est pas liée à l’espèce: 31,5% chez les ovins, 30% chez les bovins et 23% chez les caprins (p = 0,131). Cette prévalence n’est pas également liée au sexe: 30% chez les femelles contre 26% chez les mâles (p = 0,379). Par ailleurs, les poids des sachets ingérés variaient significativement d’une espèce à l’autre (p < 0,001). Ainsi les bovins et ovins avaient tendance à en consommer plus que les caprins (p < 0,05). Les poids vifs et carcasses des animaux ayant ingérés des sachets plastiques sont sensiblement égaux à ceux qui n’en ont pas ingérés. Notre étude suggère que des dispositions particulières soient prises, notamment l’élevage en stabulation et la sensibilisation à l’usage et gestion des sachets dans les villes.   Natural pastures are the main alimentary resource for ruminants in the urban and peri-urban area of Dori. These natural pastures are not only insufficient for the animals but also polluted by plastic bags. This food insufficiency (quantitative and qualitative) leads ruminants to ingest plastic bags. The general objective of our study was to investigate the prevalence of plastic bag ingestion in ruminants (cattle, goats and sheep). It was conducted from February to June 2021 through random data collection at the abattoir on 600 samples of domestic ruminants: 200 cattle, 200 goats and 200 sheep. Our results revealed that the prevalence of plastic ingestion is not related to species: 31.5% in sheep, 30% in cattle and 23% in goats (p = 0.131). This prevalence was also not linked to sex: 30% in females versus 26% in males (p = 0.379). Furthermore, the weights of the plastic bags ingested varied significantly between species (p < 0.001). Cattle and sheep tended to consume more than goats (p < 0.05). The live and carcass weights of animals that ingested plastic bags were approximately equal to those that did not. Our study suggests that special measures should be taken, including stall breeding and sensitisation on the use and management of bags in cities

Impact des Déchets Plastiques sur les Pâturages Urbains et Péri-urbains de la Ville de Dori, Région du Sahel : cas des Ruminants Domestiques

Les pâturages naturels constituent la principale ressource alimentaire des ruminants dans la zone urbaine et péri-urbaine de Dori. Ces pâturages naturels sont non seulement insuffisants pour les animaux mais aussi pollués par les sachets plastiques. Cette insuffisance alimentaire (quantitative et qualitative) amène les ruminants à ingérer des sachets plastiques. Notre étude avait pour objectif général d’étudier la prévalence de l’ingestion des sachets plastiques chez les ruminants (bovins, caprins et ovins). Elle s’est déroulée de février à juin 2021 par une collecte aléatoire de données à l’abattoir sur 600 échantillons de ruminants domestiques : 200 bovins, 200 caprins et 200 ovins. Nos résultats ont révélé que la prévalence de l’ingestion des sachets n’est pas liée à l’espèce: 31,5% chez les ovins, 30% chez les bovins et 23% chez les caprins (p = 0,131). Cette prévalence n’est pas également liée au sexe: 30% chez les femelles contre 26% chez les mâles (p = 0,379). Par ailleurs, les poids des sachets ingérés variaient significativement d’une espèce à l’autre (p < 0,001). Ainsi les bovins et ovins avaient tendance à en consommer plus que les caprins (p < 0,05). Les poids vifs et carcasses des animaux ayant ingérés des sachets plastiques sont sensiblement égaux à ceux qui n’en ont pas ingérés. Notre étude suggère que des dispositions particulières soient prises, notamment l’élevage en stabulation et la sensibilisation à l’usage et gestion des sachets dans les villes.   Natural pastures are the main alimentary resource for ruminants in the urban and peri-urban area of Dori. These natural pastures are not only insufficient for the animals but also polluted by plastic bags. This food insufficiency (quantitative and qualitative) leads ruminants to ingest plastic bags. The general objective of our study was to investigate the prevalence of plastic bag ingestion in ruminants (cattle, goats and sheep). It was conducted from February to June 2021 through random data collection at the abattoir on 600 samples of domestic ruminants: 200 cattle, 200 goats and 200 sheep. Our results revealed that the prevalence of plastic ingestion is not related to species: 31.5% in sheep, 30% in cattle and 23% in goats (p = 0.131). This prevalence was also not linked to sex: 30% in females versus 26% in males (p = 0.379). Furthermore, the weights of the plastic bags ingested varied significantly between species (p < 0.001). Cattle and sheep tended to consume more than goats (p < 0.05). The live and carcass weights of animals that ingested plastic bags were approximately equal to those that did not. Our study suggests that special measures should be taken, including stall breeding and sensitisation on the use and management of bags in cities

Impact des Déchets Plastiques dans l’Alimentation des Ruminants Domestiques: cas de l’Élevage Urbain et Périurbain de la Ville de Dori, Région du Sahel

Les pâturages naturels constituent la principale ressource alimentaire des ruminants dans la zone urbaine et péri-urbaine de Dori. Ces pâturages naturels sont non seulement insuffisants pour les animaux mais aussi pollués par les sachets plastiques. Cette insuffisance alimentaire quantitative et qualitative amène les ruminants à ingérer des sachets plastiques. La presente étude avait pour objectif général d’étudier la prévalence de l’ingestion des sachets plastiques chez les ruminants, notamment des bovins, caprins et ovins. Elle s’est déroulée de février à juin 2021 par une collecte aléatoire de données à l’abattoir de Dori lors d’une étude tranversale sur un échantillon de 600 ruminants domestiques : 200 bovins, 200 caprins et 200 ovins. Les résultats ont révélé que la prévalence de l’ingestion des sachets n’est pas liée à l’espèce: 31,5% chez les ovins, 30% chez les bovins et 23% chez les caprins (p = 0,131). Cette prévalence n’est pas également liée au sexe: 30% chez les femelles contre 26% chez les mâles (p = 0,379). Par ailleurs, les poids des sachets ingérés variaient significativement d’une espèce à l’autre (p < 0,001). Ainsi les bovins et ovins avaient tendance à en consommer plus que les caprins (p < 0,05). Les animaux qui ingéraient une quantité de sachets inférieure à 100 g étaient plus nombeux que ceux en consommaient plus (p < 0,001). Ainsi, l’ingestion n’a pas eu d’effet sur les poids vifs et carcasses des animaux ayant ingérés des sachets plastiques. L’étude suggère que des dispositions particulières soient prises, notamment l’élevage en stabulation et la sensibilisation à l’usage et à une meilleure gestion des sachets plastiques dans la commune de Dori.   Natural pastures are the main alimentary resource for ruminants in the urban and peri-urban area of Dori. These natural pastures are not only insufficient for the animals but also polluted by plastic bags. This quantitative and qualitative food insufficiency leads ruminants to ingest plastic bags. The general objective of this study was to investigate the prevalence of plastic bag ingestion in ruminants, including cattle, goats and sheep. It was conducted from February to June 2021 through random data collection at the Dori abattoir during a cross-sectional study on a sample of 600 domestic ruminants: 200 cattle, 200 goats and 200 sheep. The results revealed that the prevalence of plastic ingestion is not related to species: 31.5% in sheep, 30% in cattle and 23% in goats (p = 0.131). This prevalence was also not linked to sex: 30% in females versus 26% in males (p = 0.379). Furthermore, the weights of the plastic bags ingested varied significantly between species (p < 0.001). Cattle and sheep tended to consume more than goats (p < 0.05). Animals that consumed less than 100 g of plastic wastes were more numerous than those that consumed more (p < 0.001). Thus, ingestion had no effect on the live and carcass weights of animals that ingested plastic bags. The study suggests that special measures should be taken, including stall breeding and sensitisation on the use and better management of bags in the Dori commune

Differences in pathogenicity and virulence of Trypanosoma brucei gambiense field isolates in experimentally infected Balb/C mice

Trypanosoma brucei gambiense (T. b. gambiense) is the major causative agent of human African trypanosomiasis (HAT). A great variety of clinical outcomes have been observed in West African foci, probably due to complex host-parasite interactions. In order to separate the roles of parasite genetic diversity and host variability, we have chosen to precisely characterize the pathogenicity and virulence of T. b. gambiense field isolates in a mouse model. Thirteen T. b. gambiense strains were studied in experimental infections, with 20 Balb/C infected mice per isolate. Mice were monitored for 30 days, in which mortality, parasitemia, anemia, and weight were recorded. Mortality rate, prepatent period, and maximum parasitemia were estimated, and a survival analysis was performed to compare strain pathogenicity. Mixed models were used to assess parasitemia dynamics, weight, and changes in Packed Cell Volume (PCV). Finally, a multivariate analysis was performed to infer relationships between all variables. A large phenotypic diversity was observed. Pathogenicity was highly variable, ranging from strains that kill their host within 9 days to a non-pathogenic strain (no deaths during the experiment). Virulence was also variable, with maximum parasitemia values ranging from 42 million to 1 billion trypanosomes/ml. Reduced PCV and weight occurred in the first two weeks of the infection, with the exception of two strains. Finally, the global analysis highlighted three groups of strains: a first group with highly pathogenic strains showing an early mortality associated with a short prepatent period; a second group of highly virulent strains with intermediate pathogenicity; and a third group of isolates characterized by low pathogenicity and virulence patterns. Such biological differences could be related to the observed clinical diversity in HAT. A better understanding of the biological pathways underlying the observed phenotypic diversity could thus help to clarify the complex nature of the host-parasite interactions that determine the resistance/susceptibility status to T. brucei gambiense

Cross border transhumance involvement in ticks and tick-borne pathogens dissemination and first evidence of Anaplasma centrale in Burkina Faso

In West Africa, cross-border transhumance, also called seasonal migration, is known to be a very important animal production strategy, as it involves about 70 to 90% of cattle. In spite of the cattle movements, some strategic areas of transhumance remain poorly explored regarding ticks and their associated pathogens investigations. The purpose of this study is to evaluate the involvement of transhumance in the spread of cattle ticks and associated pathogens in Burkina Faso (BF) and Benin (BN), in a context of speedy invasion of West African livestock by Rhipicephalus microplus. A longitudinal survey was performed on 210 cattle from BF, monitored for ticks and tick-borne pathogens (TBP) during one seasonal transhumance. The first sampling coded “T0BF” took place in eastern BF, at the transhumance departure. A second sampling “T1BN” was carried out in northern BN, the transhumance arrival zone. A third sampling “T2BF” was done at the return of cattle in eastern BF. Ticks were morphologically identified and TBP detected with reverse line blot hybridization (RLB) assay. A total of 1027 ticks (7 species), 1006 ticks (11 species) and 1211 ticks (9 species) were respectively found at T0BF, T1BN and T2BF. Some species were collected at the three times of sampling without any significant difference in their relative abundances. However, other tick species appeared only at T1BN and/or T2BF. The TBP species found at the three points surveyed were Theileria annulata, Theileria mutans, Theileria velifera, Babesia bigemina and Anaplasma marginale. The most prevalent was T. mutans with 166/210 (79%), 159/210 (75.7%) and 78/210 (37%) cattle positive respectively at T0BF, T1BN and T2BF. Anaplasma centrale was evidenced with 0.5% and 0.9% respectively at T0BF and T2BF. To our knowledge, this represents its first report in the study area. Overall, the TBP prevalences were significantly lower at T2BF, highlighting the effect of tick populations changes induced by transhumance combined with the seasonal variation influence.The Academy of Research and Higher Education (ARES-CCD) [RPD Transticks].https://www.elsevier.com/locate/ttbdishj2022Veterinary Tropical Disease

Candidate gene polymorphisms study between human African trypanosomiasis clinical phenotypes in Guinea

Human African trypanosomiasis (HAT), a lethal disease induced by Trypanosoma brucei gambiense, has a range of clinical outcomes in its human host in West Africa: an acute form progressing rapidly to second stage, spontaneous self-cure and individuals able to regulate parasitaemia at very low levels, have all been reported from endemic foci. In order to test if this clinical diversity is influenced by host genetic determinants, the association between candidate gene polymorphisms and HAT outcome was investigated in populations from HAT active foci in Guinea.Samples were collected from 425 individuals; comprising of 232 HAT cases, 79 subjects with long lasting positive and specific serology but negative parasitology and 114 endemic controls. Genotypes of 28 SNPs in eight genes passed quality control and were used for an association analysis. IL6 rs1818879 allele A (p = 0.0001, OR = 0.39, CI95 = [0.24-0.63], BONF = 0.0034) was associated with a lower risk of progressing from latent infection to active disease. MIF rs36086171 allele G seemed to be associated with an increased risk (p = 0.0239, OR = 1.65, CI95 = [1.07-2.53], BONF = 0.6697) but did not remain significant after Bonferroni correction. Similarly MIF rs12483859 C allele seems be associated with latent infections (p = 0.0077, OR = 1.86, CI95 = [1.18-2.95], BONF = 0.2157). We confirmed earlier observations that APOL1 G2 allele (DEL) (p = 0.0011, OR = 2.70, CI95 = [1.49-4.91], BONF = 0.0301) is associated with a higher risk and APOL1 G1 polymorphism (p = 0.0005, OR = 0.45, CI95 = [0.29-0.70], BONF = 0.0129) with a lower risk of developing HAT. No associations were found with other candidate genes.Our data show that host genes are involved in modulating Trypanosoma brucei gambiense infection outcome in infected individuals from Guinea with IL6 rs1818879 being associated with a lower risk of progressing to active HAT. These results enhance our understanding of host-parasite interactions and, ultimately, may lead to the development of new control tools

Macrophage migrating inhibitory factor expression is associated with Trypanosoma brucei gambiense infection and is controlled by trans-acting expression quantitative trait loci in the Guinean population

Infection by Trypanosoma brucei gambiense is characterized by a wide array of clinical outcomes, ranging from asymptomatic to acute disease and even spontaneous cure. In this study, we investigated the association between macrophage migrating inhibitory factor (MIF), an important pro-inflammatory cytokine that plays a central role in both innate and acquired immunity, and disease outcome during T. b. gambiense infection. A comparative expression analysis of patients, individuals with latent infection and controls found that MIF had significantly higher expression in patients (n=141; 1.25 +/- 0.07; p<.0001) and latent infections (n=25; 1.23 +/- 0.13; p=.0005) relative to controls (n=46; 0.94 +/- 0.11). Furthermore, expression decreased significantly after treatment (patients before treatment n=33; 1.40 +/- 0.18 versus patients after treatment n=33; 0.99 +/- 0.10, p=.0001). We conducted a genome wide eQTL analysis on 29 controls, 128 cases and 15 latently infected individuals for whom expression and genotype data were both available. Four loci, including one containing the chemokine CXCL13, were found to associate with MIF expression. Genes at these loci are candidate regulators of increased expression of MIF after infection. Our study is the first data demonstrating that MIF expression is elevated in T. b. gambiense-infected human hosts but does not appear to contribute to pathology