In vitro AND in vivo ANTHELMINTIC EFFECT OF Coffea arabica RESIDUES AGAINTS AN Haemonchus contortus ISOLATE WITH LOW SUSCEPTIBILITY TO TANNINS

Abstract

The present study evaluated in vitro and in vivo anthelmintic (AH) effect of the percolated by-product of Coffea arabica against a Haemonchus contortus isolate with low susceptibility to tannins. Firstly, the susceptibility to tannins of Paraíso H. contortus isolate was evaluated with the in vitro larval exsheathment inhibition assay (LEIA) using an acetone:water (70:30) extract of Acacia pennatula. Afterwards, the in vitro AH effect of acetone:water extracts of percolated C. arabica by-products (Clean and Smooth (CS) and Shade Grown (SG) Starbucks®) were evaluated. Then, the in vivo AH effect was determined in growing sheep (4 months old and 15.2 kg bodyweight), infected with H. contortus (Paraiso isolate) and fed with a diet containing the percolated by-product of C. arabica. Three experimental groups were formed (n = 6 lambs): GC Group (control diet without C. arabica), GCA Group (feed containing 10% C. arabica) and, GCA+PEG (polyethilenglycol) Group (feed with 10% C. arabica + PEG as a tannin inhibitor). Fecal samples were obtained daily from the rectum of lambs (days 1 to 20 of the study). The H. contortus isolate tolerated the A. pennatula extract at concentrations of 150 and 300 μg extract/ml PBS (P > 0.05), which confirmed its low susceptibility to tannins. The C. arabica CS extract reduced the exsheatment from 150 μg of extract/ml PBS and the SG variety from 1200 μg of extract/ml PBS (P<0.05). The consumption of the C. arabica percolated by-product did not reduce the egg excretion of H. contortus (either per gram of feces or total eggs in feces) (P>0.05). In conclusion, the C. arabica percolated by-product extracts showed in vitro AH effect against exsheathment. However, the consumption of feed containing 10% of the percolated by-product did not show an in vivo AH effect in sheep infected with the Paraiso H. contortus isolate. The latter could be due to the low susceptibility towards the secondary compounds of tannin rich plants of the H. contortus isolate used in this study.