In vitro anthelmintic effects of Bridelia ferruginea, Combretum glutinosum, and Mitragyna inermis leaf extracts on Haemonchus contortus, an abomasal nematode of small ruminants.

Gastrointestinal nematodes remain a major constraint on the health, welfare, and production of small ruminants. This study was conducted to evaluate three plant extracts (from Bridelia ferruginea, Combretum glutinosum, and Mitragyna inermis) as effective remedies against gastrointestinal parasites of small ruminants. Phytochemical screening was conducted on the plant leaves, and the potential anthelmintic properties of these plants were tested in vitro on Haemonchus contortus using the egg hatch, larval migration, and adult worm motility assays. The phytochemical screening of the leaves revealed the presence of several bioactive components in all the plants. The number of eggs that hatched was reduced in a concentration-dependent manner (p < 0.01) upon treatment with the methanol extract of B. ferruginea and the acetone extracts of C. glutinosum and M. inermis. The inhibitory effect of the acetone extract of B. ferruginea and the methanol extracts of C. glutinosum and M. inermis was not concentration-dependent (p > 0.05). There was a significant difference (p < 0.05) in the reduction in larval migration between the lowest concentrations (75 to 150 µg/mL) and the highest concentrations (300 to 1200 µg/mL) of plant extracts. The ability of plant extracts to affect the mobility of the adult worms was not concentration-dependent (p > 0.05); however, it was dependent on the time of incubation (p < 0.01). At the highest concentration (2400 µg/mL), all adult worms were motionless after 24 h of exposure, while at the lowest concentration (< 150 µg/mL), this occurred after 48 h of exposure. M. inermis and C. glutinosum extracts were more effective than B. ferruginea extracts (p < 0.05). Overall, these results suggest that these plants used by small-scale farmers possess antiparasitic properties useful for helminthiasis control. However, the effects of the plants remain to be confirmed via in vivo assays and toxicity tests in further studies.

Differences in genetic structure assessed using Y-chromosome and mitochondrial DNA markers do not shape the contributions to diversity in African sires.

Up to 173 African sires belonging to 11 different subpopulations representative of four cattle groups were analysed for six Y-specific microsatellite loci and a mitochondrial DNA fragment. Differences in Y-chromosome and mtDNA haplotype structuring were assessed. In addition, the effect of such structuring on contributions to total genetic diversity was assessed. Thirty-five Y-chromosome and 71 mtDNA haplotypes were identified. Most Y-chromosomes analysed (73.4%) were of zebu origin (11 haplotypes). Twenty-two Y-haplotypes (44 samples) belonged to the African taurine subfamily Y2a. All mtDNA haplotypes belonged to the "African" taurine T1 haplogroup with 16 samples and nine haplotypes belonging to a recently identified subhaplogroup (T1e). Median-joining networks showed that Y-chromosome phylogenies were highly reticulated with clear separation between zebu and taurine clusters. Mitochondrial haplotypes showed a clear star-like shape with small number of mutations separating haplotypes. Mitochondrial-based FST -statistics computed between cattle groups tended to be statistically non-significant (p > .05). Most FST values computed among groups and subpopulations using Y-chromosome markers were statistically significant. AMOVA confirmed that divergence between cattle groups was only significant for Y-chromosome markers (ΦCT  = 0.209). At the mitochondrial level, African sires resembled an undifferentiated population with individuals explaining 94.3% of the total variance. Whatever the markers considered, the highest contributions to total Nei's gene diversity and allelic richness were found in West African cattle. Genetic structuring had no effect on patterns of contributions to diversity.

A review on aflatoxin contamination and its implications in the developing world: a sub-Saharan African perspective.

Mycotoxins contamination in some agricultural food commodities seriously impact human and animal health and reduce the commercial value of crops. Mycotoxins are toxic secondary metabolites produced by fungi that contaminate agricultural commodities pre- or postharvest. Africa is one of the continents where environmental, agricultural and storage conditions of food commodities are conducive of Aspergillus fungi infection and aflatoxin biosynthesis. This paper reviews the commodity-wise aetiology and contamination process of aflatoxins and evaluates the potential risk of exposure from common African foods. Possible ways of reducing risk for fungal infection and aflatoxin development that are relevant to the African context. The presented database would be useful as benchmark information for development and prioritization of future research. There is need for more investigations on food quality and safety by making available advanced advanced equipments and analytical methods as well as surveillance and awareness creation in the region.