Addressing anthelmintic resistance in Haemonchus contortus strains in small ruminants through alternative strategies with a focus on Moringa oleifera extracts

Abstract

Anthelmintic resistance poses a significant threat to small-stock farming worldwide, with Haemonchus contortus being a major contributor to production losses and the deterioration of animal health. This study aimed to evaluate the potential use of Moringa oleifera (M. oleifera) in livestock production systems to combat Haemonchosis and anthelmintic resistance in small stock farms. This growing crisis threatens the sustainability of small-stock production, particularly in tropical regions where parasitic loads are high. One promising alternative to combat Haemonchosis is the use of phytochemical compounds derived from M. oleifera. In vitro inhibitory effects of M. oleifera on Haemonchus contortus larval motility and egg hatchability have been previously reported in literature. In the current study ethanolic extracts from commercially sourced M. oleifera leaf and seed samples were analysed for phytochemical composition through UPLC-UV/QTOF/MS. Previous research reported that terpenoids, cinnamic acids, alkaloids, flavones and saponins are effective biochemical compounds against Haemonchus contortus. The analysis of the crude M. oleifera leaf and seed extracts revealed the presence of potentially bioactive menthane monoterpenoids, secoiridoid monoterpenoids and cinnamic acids like cimicifugic acid. This highlighted the potential for M. oleifera to be included in management strategies against Haemonchosis in livestock. The M. oleifera extracts were further fractionated into seven (leaves) and five fractions (seeds) according to polarity and evaluated for their effects on larval motility and egg hatchability in vitro. For M. oleifera leaves, the average crude extract egg mortalities were recorded as 89.0%, 76.7%, and 100.0% for concentrations of 5, 10, and 15 mg/ml respectively. Similarly, the average crude extract larvae mortalities were 30.1%, 51.8%, and 54.3% for the same concentrations. Regarding M. oleifera seed extracts, the average egg mortalities were 80.7%, 95%, and 76.5% for concentrations of 5, 10, and 15 mg/ml respectively. Correspondingly, the average crude extract larval mortalities were 25.6%, 25.1%, and 28.9% for the same concentrations. Fraction 6 from M. oleifera leaves and fractions 5 and 3 from seeds exhibited the highest mortality percentages for both egg hatch and larval survivability assays, reaching up to 96.9% and 94.5% for leaves, and 94.6% and 71.4% for seeds respectively. By exploring innovative alternative approaches to address the challenge of anthelmintic resistance, this study aimed to potentially enhance the resilience and sustainability of the sheep production sector, concurrently fostering animal health and welfare.