Laya Sawadogo

Comparative pathogenicity of three genetically distinct types of Trypanosoma congolense in cattle : Clinical observations and haematological changes

The pathology of African bovine trypanosomosis was compared in Zebu cattle subcutaneously inoculated with three clones of trypanosomes corresponding to the three genetically distinct types of Trypanosoma congolense; savannah-type, west African riverine/forest-type and kilifi-type. All inoculated animals became parasitaemic between 7 and 11 days post-infection (dpi). The savannah-type showed consistently higher levels of parasitaemia and lower packed red cell volume percentages and leukocyte counts than the other two types. The syndrome was also more severe in the savannah-type and led inexorably to death between 29 and 54 dpi while animals with the forest or the kilifi-types recovered from earlier symptoms and haematological alterations after 3 months of infection. By the end of the experiment, the animals self-cured from the forest-type infection and the kilifi-type passed under control. The results of the present study indicated clear difference in pathogenicity between the three types of T. congolense; the savannah-type was virulent while the forest-type was of low pathogenicity and the kilifi-type was non-pathogenic.

Pregnancy-associated glycoprotein concentrations during pregnancy and the postpartum period in Azawak Zebu cattle

Specific RIA systems were developed and used to measure pregnancy-associated glycoprotein (PAG) concentrations during gestation and the postpartum period in Azawak Zebu cows. Twelve females were palpated per rectum and diagnosed as pregnant. Blood samples were taken at 5-10-day intervals from approximately Week 8 of gestation until Week 10 postpartum (pp). One Zebu cow (Z15) initially diagnosed as pregnant showed PAG concentrations lower than the assay sensitivity (<0.20 ng/ml) and did not calve. Another cow (ZSand) showed abnormally high PAG concentrations during gestation and was excluded from the general PAG profile. The 10 other Zebu cows exhibited a very similar PAG profile. In these animals, concentrations increased progressively from Week 8 to 35 of gestation (from 6.0+/-4.2 to 196.0+/-34.8 ng/ml), remaining relatively constant until Week 39 (210.8+/-74.8 ng/ml), when they increased sharply to reach their highest level (1095.6+/-607.2 ng/ml) at around parturition. After delivery, PAG concentrations declined significantly (P<0.05) until Week 2 postpartum (348.4+/-85.6 ng/ml) and slowly until Week 10 postpartum. Our results revealed that the PAG pattern in Zebu cattle was similar to those of taurine breeds during the first two trimesters of pregnancy, but differed in the peripartum period.

Microsatellite analysis characterizes Burkina Faso as a genetic contact zone between Sahelian and Djallonke sheep.

A total of 123 sheep belonging to the Djallonké, Mossi, and Burkina-Sahel breeds, along with 41 Spanish Xalda sheep were genotyped for 27 microsatellites. The pair Djallonké-Mossi had the highest between breeds molecular coancestry. Admixture analysis informed on the parental role of the Burkina-Sahel and Djallonké breeds. The Mossi breed was a hybrid population nearer to the Djallonké breed. Only half of the Mossi individuals were correctly assigned to their breed. The Burkina-Sahel and Djallonké breeds can be considered ancestrally different genetic entities. Differentiation between the Djallonké and Mossi breeds may be due to introgression of Sahelian sheep.

Comparative pathogenicity of three genetically distinct Trypanosoma congolense-types in inbred Balb/c mice.

Inbred Balb/c mice were infected with three clones of Trypanosoma congolense (Sam.28.1, Dind.3.1 and K60.1A) corresponding, respectively, to the three genetically distinct types (savannah, forest and kilifi) defined within this species, for the purpose of comparing their pathogenicity for a better understanding of the epidemiology of African trypanosomosis. Another clone of savannah type, IL 3000, was also tested simultaneously to study a probable strain variation. Both the clones of savannah type were found of extreme virulence with loss of appetite, rough hair, rapid respiration, lethargy, and all mice died within a week. Parasitaemias evolved rapidly to the first peak by day 3-5 post-inoculation without any remission and the course of disease was correlated positively with the prepatent period. The clones of the forest type and the kilifi type were of low virulence with chronic infection and symptoms progressively less patent throughout the infection; only one mouse died in each experimental group.

Analysis of mitochondrial DNA diversity in Burkina Faso populations confirms the maternal genetic homogeneity of the West African goat.

To date, no comprehensive study has been performed on mitochondrial genetic diversity of the West African goat. Here, we analysed a 481-bp fragment of the HVI region of 111 goats representing four native West African populations, namely the three main Burkina Faso breeds, zoo-farm kept Dwarf goats and endangered Spanish goat breeds used as the outgroup. Analyses gave 83 different haplotypes with 102 variable sites. Most haplotypes (65) were unique. Only three haplotypes were shared between populations. Haplotypes were assigned to cluster A except for H45 (belonging to the Spanish Bermeya goat) which was assigned to cluster C. amova analysis showed that divergence between groups (Phi(CT)) was not statistically significant regardless of whether the partition in two hierarchical levels that was fitted included Spanish samples or not. The West African goat scenario shown here is consistent with that previously reported for the species: haplogroup A is predominant and has a very high haplotype diversity regardless of the geographic area or sampled breed. The large phenotypic differences observable between the West African Dwarf and Sahelian long-legged goat populations are not detectable with mitochondrial markers. Moreover, a previously suggested introgression of Sahelian goat southwards because of desertification could not be assessed using mtDNA information.

Free radical scavenging capacity, anticandicidal effect of bioactive compounds from Sida Cordifolia L., in combination with nystatin and clotrimazole and their effect on specific immune response in rats

BackgroundInfectious diseases caused by fungi are still a major threat to public health, despite numerous efforts by researchers. Use of ethnopharmacological knowledge is one attractive way to reduce empiricism and enhance the probability of success in new drug-finding efforts. In this work, the total alkaloid compounds (AC) from Sida cordifolia L. (Malvaceae) have been investigated for their free radical scavenging capacity, antifungal and immunostimulatory properties.MethodThe antifungal activity was investigated against five candida strains using the microplate dilution method and the Fractional Inhibitory Concentration Index (FICI) of compounds was evaluated. The antioxidant activity of the samples was evaluate using three separate methods, at last, the immunostimulatory effect on immunosuppressed wistar rats was performed.ResultsAs for the antifungal activity, result varied according to microorganism. The results obtained in this antifungal activity were interesting and indicated a synergistic effect between alkaloid compounds and the antifungal references such as Nystatin and Clotrimazole. Antioxidant capacity noticed that the reduction capacity of DPPH radicals obtained the best result comparatively to the others methods of free radical scavenging. Our results showed a low immunostimulatory effect and this result could be explained by the lack of biologically active antioxidants such as polyphenol compounds lowly contained in the alkaloid compounds.ConclusionThe results of this study showed that alkaloid compounds in combination with antifungal references (Nystatin and Clotrimazole) exhibited antimicrobial effects against candida strains tested. The results supported the utilization of these plants in infectious diseases particularly in treatment of candida infections.

Combined effects of testosterone propionate and Leptadenia hastata Pers. (Decne) aqueous extracts on immature castrated male rats

To evaluate the competition between testosterone propionate (TP) and Leptadenia hastata aqueous extracts, immature castrated male Wistar rats were divided into two groups. L. hastata aqueous extracts reduced significantly the weight of androgen-dependant sex glands, the level of phosphatase acid prostatic (PAP) and fructose in seminal vesicles and prostate, and the serum testosterone level. When TP was administered simultaneously with 100, 200 and 400 mg/kg of L. hastata aqueous extracts, a potentiate action was observed with 100 mg/kg of L. hastata by the increase of androgen-dependant sex glands weights, fructose and PAP levels in seminal vesicles and prostate, and the serum testosterone level. The anti-androgenic effect of L. hastata appeared with the doses of 200 and 400 mg/kg which reduced significantly the weight of androgen-dependant sex glands, fructose and PAP levels in seminal vesicles and prostate and serum testosterone level. From these findings, it was concluded that the effect of TP was potentiated with low doses of L. hastata and antagonized with high doses. This study confirmed the anti-androgenic effects of L. hastata aqueous extracts in immature castrated male rats. Key words: Leptadenia hastata , testosterone propionate, anti-androgenic activity, rats. INTRODUCTION The increasing interest in the effects of the components of plant extracts on humans and wildlife has been reflected in the number of recent papers and international conferences devoted to this topic (Weisburger, 1999; Arbonnier, 2000; Vasudeva and Sharma, 2006). Plant-derived chemicals that influence endocrine activities in both humans and animals have received a great deal of attention due to their possible beneficial as well as adverse effects (Gamache and Acworth, 1998). Leptadenia hastata (Pers.) Decne (Asclepediaceae) is an indigenous medicinal plant of West Africa, commonly

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.

Efficacite d’un traitement de maitrise des cycles chez les zebus: oestrus induit et fertilite

L’efficacite d’un traitement de maitrise des cycles oestraux a ete appreciee sur deux races de zebus en elevage semi-intensif du Burkina Faso. L’essai a permis de determiner les proportions d’oestrus induits et de fertilite sur 170 femelles zebus Azawak et zebu Goudali traitees aux implants de norgestomet. Le traitement au norgestomet a consiste a la pose d’un implant a l’oreille pour une duree de 10 jours. Cette pose a ete suivie de deux injections de 2 ml (500 μg) de prostaglandine (Eustrumate) et 2 ml (400 UI) de PMSG (folligon) respectivement aux jours 8 et 10. Le critere majeur de venu en oestrus a ete l’acceptation du chevauchement. Les inseminations ont ete pratiquees en double 48 heures et 72 heures apres la fin du traitement. Le taux moyen d’oestrus induit a ete de 92,9%. Le delai moyen d’apparition de l’oestrus a ete de 33,15 ± 4,35 heures avec des variations entre types raciales. La duree moyenne de l’oestrus a ete de 11,7 ± 1,9 heures. Le taux moyen de fertilite a ete de 31,1%. Mot cles: zebu, oestrus induit, insemination artificielle, norgestomet English Abstract The efficiency of a estrous induced treatments was monitored on two zebu race in semi-intensives farms of Burkina Faso. The assay determined the rate of induced estrus and fertility on 170 zebu Azawak and zebu Goudali cows treated with norgestomet implant. The treatment Azawak zebu cows received Norgestomet ear implant for 10 days associated with estradiol valerate (2ml), and followed with PGF 2α ( 500 μg) and PMSG (400 UI) im injections respectively at days 8 and 10. Inseminations were practiced in double 48 hours and 72 hours after the end of the treatment. The proportion of estrus induced was 92.9% and was significantly affected (P < 0.05) by hormonal treatment. The elapsed time of estrus display was 33.15 ± 4.35 hours with variations between zebu types. The average length of estrus was 11.7 ± 1.9 hours. The average rate of fertility was of 31.1%. Keywords: zebu, estrus induced, artificial insemination, norgestomet