An in vitro approach to evaluate the nutraceutical value of plant foliage against Haemonchus contortus

Nutraceutical plants provide nutrients for the animal as well as secondary compounds that can affect the biology and survival of gastrointestinal nematodes (GIN). Current screening of nutraceutical plants is based on in vitro evidence of anthelmintic (AH) activity against different life stages of GIN, but nutritional information is omitted or scarce. This study proposes an integral in vitro screening protocol to identify the nutraceutical value of the foliage from plant species consumed by small ruminants, using Haemonchus contortus as a biological model. The leaves from Acacia collinsii, A. pennatula, Bunchosia swartziana, Gymnopodium floribundum, Havardia albicans, Leucaena leucocephala, Lysiloma latisiliquum, Mimosa bahamensis, Piscidia piscipula, and Senegalia gaumeri were evaluated for their chemical composition and in vitro digestibility. Acetone:water extracts (70:30) from leaves of each plant were evaluated using the egg hatch assay and larval exsheathment inhibition assay. Respective effective concentrations 50% (EC50) were determined for each assay. The ten plant species showed good nutritional value for ruminants, including crude protein (> 10%), metabolizable energy (> 2.9 MJ/kg DM), and varied CT content (from 1.0 to 37.6%). The best AH activity against H. contortus eggs (EC50 = 401.8 μg/mL) and L3 (EC50 = 83.1 μg/mL) was observed for S. gaumeri extract. Although all the plant species showed in vitro nutraceutical potential, the leaves of S. gaumeri had the best values. The proposed in vitro protocol showed to be useful for the integral assessment of the nutraceutical potential of different plant species as it included the nutritional value and the AH activity against eggs and L3 in the selected plant species

In vitro ASSESSMENT OF EDIBLE MUSHROOM EXTRACTS IN THE LARVAL EXSHEATHMENT TEST AGAINST Haemonchus contortus

Background. Worldwide, gastrointestinal nematodes (GIN) cause losses in livestock production, because in some animals they can cause weight loss or death. Combating these GIN has been based on the use of anthelmintics. However, the misuse of these treatments has caused anthelmintic resistance. Therefore, there is currently a search for new biological alternatives for the control of gastrointestinal nematodes. One of these alternatives is the use of fungal extracts for nematode control. Objectives. To utilize the in vitro larval exsheathment inhibition test to evaluate organic extracts of edible fungi Pleurotus eryngii, P. djamor and Lentinula edodes, against Haemonchus contortus (L3). Methodology. Extracts were prepared from the basidiomes of the fungal species mentioned. In the case of P. eryngii and P. djamor, they were placed in a hydroalcoholic mixture (methanol/water 70:30). On the other hand, L. edodes basidiomes were macerated with distilled water for 24 hours. The extracts were filtered with a cotton/gauze system and through Whatman paper (#4) and were concentrated using a rotary evaporator until the liquid residue was removed and kept at -4 °C until use. To determine the percentage of larval exsheathment inhibition, larvae were exposed to different concentrations (156.25, 312.5, 625, 1250, and 2500 µg/mL) with their respective negative controls (PBS) for 60 minutes. The effective concentration 50% (EC50) was calculated by means of probit analysis. Results. The extracts with the best activity were P. djamor and L. edodes with an effective concentration (EC50) of 533.3 and 558.5 µg/mL, respectively. Implications. This in vitro evaluation provides results that suggest the need for further in vitro studies with more fungi species and other types of extraction procedures. Conclusion. The present study demonstrated that the use of extracts of P. eryngii, P. djamor and L. edodes was shown to have in vitro anthelmintic activity against the larval exsheathment of H. contortus