Identification of Streptococcus suis Meningitis by Direct Triplex Real-Time PCR, Burkina Faso.

Meningitis confirmation in Burkina Faso uses PCR for detecting Streptococcus pneumoniae, Neisseria meningitidis, or Hemophilus influenzae. We identified 38 cases of meningitis among 590 that were PCR-positive for 3 nonpneumococcal streptococcal pathogens, including 21 cases of Streptococcus suis. Among the country's 13 regions, 10 had S. suis-positive cases.

Effects of Acacia mearnsii supplementation on nutrition, parasitological, blood parameters and methane emissions in Santa Inês sheep infected with Trichostrongylus colubriformis and Haemonchus contortus.

Gastrointestinal nematodes are a main problem for ruminant production, reducing animal performance and increasing environmental impact per unit of animal product generated. Tannin supplementation may lead to positive results regarding aspects such as parasitic infections and methane (CH4) emissions. Therefore, the objective of this experiment was to evaluate the effects of the condensed tannins (CT) extract made of powdered Acacia mearnsii bark (PAB) on nutrition, parasitic status and CH4 emissions in sheep artificially infected with Trichostrongylus colubriformis and Haemonchus contortus. Twenty 10-month old Santa Inês lambs (24.7 ± 3.14 kg of initial body weight) were used in a 50-day trial. Animals were divided in four treatment groups according to parasitic infection and PAB supplementation: two control groups without infections, one without PAB (C-) (n = 4) and one with PAB (C+) (n = 4); two infected groups, one without PAB (I-) (n = 6) and another receiving PAB (I+) (n = 6). Initially, animals were kept in individual pens where they were fed ad libitum chopped tifton 85 hay (Cynodon spp.) and 210 g/animal/day of concentrate. On the first day of experiment, animals of I- and I+ groups were artificially infected with infective larvae (L3) of T. colubriformis and H. contortus. Lambs were weighed fortnightly to calculate average daily body weight gain (ADG). Blood and faeces samples were also collected in the same moment of weighing for the evaluation of blood parameters and faecal egg count (FEC) respectively. After 40 days of experiment, measurements of CH4 emissions in small chamber system started and following that, apparent total tract digestibility (ATTD) assay was carried out in metabolic cages. In the end of experimental period (50 days), lambs were slaughtered and samples of abomasum and small intestine content were collected for worm count, identification, and eggs/female count. No significant (p > 0.05) treatment effects were verified for ADG, ATTD and worm count. Blood parameters were affected in both infected groups (p < 0.05) from the 28th experimental day onwards, when these animals started to show reduced red blood cells, haemoglobin and packed cell volume when compared to C- and C+. Decreased FEC was verified in I+ when compared to I- and also, H. contortus eggs/female worm for I+ was lower than for I- (p < 0.05). Both infected groups showed higher CH4 emissions than the control groups (p < 0.05). Results highlighted the anthelmintic potential of PAB and indicated methanogenic effect of parasitic nematode infections.

Geographical assessment of body measurements and qualitative traits in West African cattle.

A total of 1015 adult cows belonging to nine West African cattle breeds were assessed for 16 body measurements and 18 qualitative traits to ascertain the existence of geographical patterns of variation. Sampling was carried out in 29 different provinces of Mali, Burkina Faso and Benin. For body measurements, taurine breeds took lower average values than the zebu breeds. Sanga cattle took intermediate values. Qualitative traits did not allow to differentiate among cattle groups (taurine, zebu or sanga) or breeds. Principal component analysis identified two factors explaining 56.4 and 9.2 % of the variance for body measurements, respectively. Two correspondence analysis dimensions computed on qualitative traits explained a small proportion of the variability (20.8 and 13.5 %, respectively). Contour plots were constructed using the eigenvalues computed for each individual and either factor or dimension identified; confidence regions calculated confirmed that body measurements clearly differentiated zebu and taurine cattle breeds while qualitative traits did not. Factor 1 was projected on a geographical map, using provinces as nodes, to assess breed-free variation for body measurements. A pattern of continuous variation from the Sahel area southwards was identified. Probably, breeding decisions promoting the crosses between zebu-like and taurine cattle are underlying this geographical pattern of variation. The implementation of selection strategies aiming at the increase of the productivity of native West African taurine cattle breeds while avoiding looses in trypanotolerant ability would be highly advisable.

In vitro anthelmintic activity of Euphorbia forskalii J. Gay aqueous extracts evaluation on different life stages of Haemonchus contortus.

The use of medicinal plants in the control of gastrointestinal parasitosis is a promising solution for improving the productivity of sheep flocks. In order to evaluate the anthelmintic activity of Euphorbia forskallii, in vitro bioassays were performed on three life stages of Haemonchus contortus. Five aqueous extracts concentrations namely 10 mg/mL; 5 mg/mL; 2.5 mg/mL; 1.25 mg/mL and 0.62 mg/mL were used for adult worm mortality tests. Egg hatch inhibition and L3 larval migration inhibition tests were studied at 5 mg/mL; 2.5 mg/mL; 1.25 mg/mL; 0.62 mg/mL and 0.31 mg/mL. A negative control PBS and a positive control levamisole 2.5 mg/mL were established for each test. A phytochemical screening was performed to determine the presence of some secondary metabolites. The results obtained showed the presence of total polyphenols, total flavonoids and condensed tannins within the aqueous extracts of E. forskalii. A high and significant (P < 0.05) morality rate compared to the negative control with an LC50 of 2.30 mg/mL was obtained. Inhibition of egg hatch and larval migration were high and significant (p < 0.05) compared to the negative control. There was an IC50 of 1.03 mg/mL and 0.92 mg/mL respectively for inhibition of egg hatching and L3 larval migration. The present study revealed the in vitro anthelmintic activity of E. forskalii aqueous extracts and allows us to consider in perspective complementary studies to confirm this activity.

Ascertaining gene flow patterns in livestock populations of developing countries: a case study in Burkina Faso goat.

BACKGROUND: Introgression of Sahel livestock genes southwards in West Africa may be favoured by human activity and the increase of the duration of the dry seasons since the 1970's. The aim of this study is to assess the gene flow patterns in Burkina Faso goat and to ascertain the most likely factors influencing geographic patterns of genetic variation in the Burkina Faso goat population. RESULTS: A total of 520 goat were sampled in 23 different locations of Burkina Faso and genotyped for a set of 19 microsatellites. Data deposited in the Dryad repository: http://dx.doi.org/10.5061/dryad.41h46j37. Although overall differentiation is poor (FST = 0.067 ± 0.003), the goat population of Burkina Faso is far from being homogeneous. Barrier analysis pointed out the existence of: a) genetic discontinuities in the Central and Southeast Burkina Faso; and b) genetic differences within the goat sampled in the Sahel or the Sudan areas of Burkina Faso. Principal component analysis and admixture proportion scores were computed for each population sampled and used to construct interpolation maps. Furthermore, Population Graph analysis revealed that the Sahel and the Sudan environmental areas of Burkina Faso were connected through a significant number of extended edges, which would be consistent with the hypothesis of long-distance dispersal. Genetic variation of Burkina Faso goat followed a geographic-related pattern. This pattern of variation is likely to be related to the presence of vectors of African animal trypanosomosis. Partial Mantel test identified the present Northern limit of trypanosome vectors as the most significant landscape boundary influencing the genetic variability of Burkina Faso goat (p = 0.008). The contribution of Sahel goat genes to the goat populations in the Northern and Eastern parts of the Sudan-Sahel area of Burkina Faso was substantial. The presence of perennial streams explains the existence of trypanosome vectors. The South half of the Nakambé river (Southern Ouagadougou) and the Mouhoun river loop determined, respectively, the Eastern and Northern limits for the expansion of Sahelian goat genes. Furthermore, results from partial Mantel test suggest that the introgression of Sahelian goat genes into Djallonké goat using human-influenced genetic corridors has a limited influence when compared to the biological boundary defined by the northern limits for the distribution of the tsetse fly. However, the genetic differences found between the goat sampled in Bobo Dioulasso and the other populations located in the Sudan area of Burkina Faso may be explained by the broad goat trade favoured by the main road of the country. CONCLUSIONS: The current analysis clearly suggests that genetic variation in Burkina Faso goat: a) follows a North to South clinal; and b) is affected by the distribution of the tsetse fly that imposes a limit to the Sahelian goat expansion due to their trypanosusceptibility. Here we show how extensive surveys on livestock populations can be useful to indirectly assess the consequences of climate change and human action in developing countries.

Prion protein gene polymorphism in four West African sheep populations.

A total of 162 individuals, belonging to three Burkinabé and one Niger sheep populations, were analysed for prion protein (PrP) gene polymorphism at codons 136, 154 and 171. The ARQ allele was the most frequent in both the Burkinabé (86.7%) and the Niger (67.5%) sheep populations. The highly sensitive allele VRQ was not found in the sampled individuals. The highly resistant ARR allele was in very low frequency in the Burkina-Sahel (4.4%) and Mossi (3.2%) populations and was not present in the Djallonké and Touareg populations. Only 4 out of 15 possible PrP genotypes were identified in the sampled individuals. No favourable ARR/ARR genotypes were found in either of the breeds. Sequencing a subgroup of the samples allowed the identification of other five polymorphisms on the PrP gene sequence at codons 116, 138, 151, 237 and 240. The very low frequency of the ARR allele in the West African sheep should dissuade the implementation of a preventive selection programme aimed to increase resistance to scrapie, to avoid an extreme erosion of the genetic stock.

Comparison of the in vitro anthelmintic effects of Acacia nilotica and Acacia raddiana.

Gastrointestinal nematodes are a major threat to small ruminant rearing in the Sahel area, where farmers traditionally use bioactive plants to control these worms, including Acacia nilotica and Acacia raddiana. The main aim of this study was to screen the potential anthelmintic properties of aqueous and acetone extracts of leaves of these two plants based on three in vitro assays: (1) the egg hatch inhibition assay (EHA); (2) the larvae exsheathment inhibition assay (LEIA) using Haemonchus contortus as a model; and (3) an adult mortality test (AMT) applied on Caenorhabditis elegans. For the EHA, only A. raddiana was effective with IC50 = 1.58 mg/mL for aqueous extract, and IC50 = 0.58 mg/mL for acetonic extract. For the LEIA, all extracts inhibited the exsheathment of larvae compared to the controls, and the aqueous extract of A. nilotica was more larvicidal with IC50 = 0.195 mg/mL. In general, all responses to the substances were dose-dependent and were significantly different from the control group (p < 0.05). For the AMT, the extracts of the two Acacia species were effective but A. raddiana showed greater efficacy with 100% mortality at 2.5 mg/mL and LC50 = 0.84 mg/mL (acetonic extract). The addition of polyvinyl polypyrrolidone (PVPP) to the extracts suggested that tannins were responsible for blocking egg eclosion and inducing adult mortality but were not responsible for exsheathment inhibition. These results suggest that the leaves of these Acacia species possess ovicidal and larvicidal activities in vitro against H. contortus, and adulticidal effects against C. elegans.