Vet Parasitol. 2016 Aug 30;227:122-9. doi: 10.1016/j.vetpar.2016.08.002. Epub 2016 Aug 3.
- 1IHAP,
Université de Toulouse, INRA, ENVT, Toulouse, France; MG 2 MIX, La
basse haye, 35220 Châteaubourg, France. Electronic address:
e.gaudin@envt.fr.
- 2IHAP, Université de Toulouse, INRA, ENVT, Toulouse, France.
- 3Toxalim, Université de Toulouse, INRA, ENVT, INP-Purpan, UPS, Toulouse, France.
- 4IHAP, Université de Toulouse, INRA, ENVT, Toulouse, France; MG 2 MIX, La basse haye, 35220 Châteaubourg, France.
Abstract
The
worldwide spread of resistance to anthelmintic (AH) drugs in
gastrointestinal nematodes (GINs) imposes to explore alternative
solutions. Amongst those, the possible use of tannin-containing
nutraceuticals appears as a relevant option to replace (or decrease the
frequency of) chemical-based treatments. Our objectives were to test the
AH efficacy of sainfoin
pellets against a multiresistant strain of Haemonchus contortus in
experimentally infected lambs and to examine possible interaction
between ivermectin (IVM) and condensed tannins (CT)-rich ressource. In
vivo study was performed with twenty-four lambs were inoculated (Day 0)
with multiresistant H. contortus infective larvae. On D21
Post-Infection, the lambs were assigned to two dietary treatments (sainfoin
vs lucerne control pellets). On D39, half of the animals per group
received 0.25ml/kg of an oral ivermectin treatment. On D47, animals were
slaughtered to count worms. The consumption of sainfoin
was associated with higher packed cell volume (PCV) values (P<0.05)
and reduced faecal egg counts (FECs) (P<0.05). For the experimental
feeding period, FECs were overall reduced by 50% in the sainfoin group. The diet did not have significant effect on the worm number but sainfoin significantly reduced female fertility. Decrease in plasma IVM concentrations was observed in the sainfoin-fed
animals and was associated with a decrease of IVM efficiency when
compared with the control group. Incubating tannin in vitro with
ivermectin and rumen fluid showed a blocking of ivermectin by the
tannins. This suggests that tannins lower the IVM intestinal absorption
compromising thereby drug plasma bioavailability and efficacy.
Tannin-containing nutraceuticals alter the biology of multiresistant
nematodes, thus representing an option for their sustainable control. In
vivo and in vitro interactions between nutraceuticals and chemicals
impose caution when both tannin-rich diet and drug-based treatments are
combined. Further studies are required to clarify the mechanisms that
support such interactions.
Copyright © 2016 Elsevier B.V. All rights reserved.
KEYWORDS:
Anthelmintic resistance; Gastrointestinal nematodes; H. contortus; Ivermectin; Sainfoin pellets
