Chicory reduces cyathostomin egg excretion and larval development

The reduction in infective larvae was remarkable, particularly when you look at the effects on larval development. Doing a little research, I was surprised to find that chicory as forage is a growing practice, but when it comes to horses, the jury is still out. Amounts, pasture management and many other questions need to be addressed before this can be recommended. See the brief overview of the potential toxicity of very large amounts of chicory in the horse’s diet below this summary.

Chicory (Cichorium intybus) reduces cyathostomin egg excretion and larval development in grazing horses
Int J Parasitol Drugs Drug Resist. 2024 Feb 9:24:100523. doi: 10.1016/j.ijpddr.2024.100523. Online ahead of print.
Authors
Joshua Malsa 1 , Leslie Boudesocque-Delaye 2 , Laurence Wimel 3 , Juliette Auclair-Ronzaud 3 , Bertrand Dumont 4 , Núria Mach 5 , Fabrice Reigner 6 , Fabrice Guégnard 7 , Angélique Chereau 7 , Delphine Serreaupment 7 , Isabelle Théry-Koné 2 , Guillaume Sallé 7 , Géraldine Fleurance 8
Affiliations

1 INRAE, Université de Tours, UMR 1282 Infectiologie et Santé Publique, Nouzilly, France. Electronic address: joshua.malsa@inrae.fr.
2 Université de Tours, EA 7502 Synthèse et Isolement de Molécules Bioactives, Tours, France.
3 Institut Français Du Cheval et de L’équitation, Plateau Technique de Chamberet, Chamberet, France.
4 INRAE, Université Clermont Auvergne, VetAgro Sup, UMR 1213 Herbivores, Saint-Genès-Champanelle, France.
5 IHAP, Université de Toulouse, INRAE, ENVT, Toulouse, Cedex 3, 31076, France.
6 INRAE, Unité Expérimentale de Physiologie Animale de L’Orfrasière, Nouzilly, France.
7 INRAE, Université de Tours, UMR 1282 Infectiologie et Santé Publique, Nouzilly, France.
8 INRAE, Université Clermont Auvergne, VetAgro Sup, UMR 1213 Herbivores, Saint-Genès-Champanelle, France; Institut Français Du Cheval et de L’équitation, Pôle Développement, Innovation et Recherche, Saint-Genès-Champanelle, France.

PMID: 38368671
DOI: 10.1016/j.ijpddr.2024.100523

Abstract

Cyathostomins are the most prevalent parasitic nematodes of grazing horses. They are responsible for colic and diarrhea in their hosts. After several decades of exposure to synthetic anthelmintics, they have evolved to become resistant to most compounds. In addition, the drug-associated environmental side-effects question their use in the field. Alternative control strategies, like bioactive forages, are needed to face these challenges. Among these, chicory (Cichorium intybus, Puna II cultivar (cv.)) is known to convey anthelmintic compounds and may control cyathostomins in grazing horses. To challenge this hypothesis, we measured fecal egg counts and the rate of larval development in 20 naturally infected young saddle horses (2-year-old) grazing either (i) a pasture sown with chicory (n = 10) or (ii) a mesophile grassland (n = 10) at the same stocking rate (2.4 livestock unit (LU)/ha). The grazing period lasted 45 days to prevent horse reinfection. Horses in the chicory group mostly grazed chicory (89% of the bites), while those of the control group grazed mainly grasses (73%). Cyathostomins egg excretion decreased in both groups throughout the experiment. Accounting for this trajectory, the fecal egg count reduction (FECR) measured in individuals grazing chicory relative to control individuals increased from 72.9% at day 16 to 85.5% at the end of the study. In addition, larval development in feces from horses grazed on chicory was reduced by more than 60% from d31 compared to control individuals. Using a metabarcoding approach, we also evidenced a significant decrease in cyathostomin species abundance in horses grazing chicory. Chicory extract enriched in sesquiterpenes lactones was tested on two cyathostomins isolates. The estimated IC50 was high (1 and 3.4 mg/ml) and varied according to the pyrantel sensitivity status of the worm isolate. We conclude that the grazing of chicory (cv. Puna II) by horses is a promising strategy for reducing cyathostomin egg excretion and larval development that may contribute to lower the reliance on synthetic anthelmintics. The underpinning modes of action remain to be explored further.

Keywords: Health management; ITS-2; Nutraceutical; Strongyles; Terpene.

Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.

Why Fructan Is Not The Issue With Pasture Laminitis

Eds. Note: you see much about the inulin content of chicory. Inulin is a form of fructan and not digestible by the horse. It is fermented by bacteria in the large bowel.

By Eleanor Kellon, VMD presented in the AAEP website
April 2022

In 2006, van Eps and Pollitt reported the induction of laminitis by administering a bolus of pure chicory root oligofructose (a fructan) by stomach tube. The amount required was 7.5 g/kg BW to induce laminitis in one foot; 10 to 12.5 g/kg for a systemic reaction and multifoot laminitis. This is a huge amount. At the lower end it equates to an 8.25 pound bolus of pure fructan for a 500 kg horse. For a horse to take in that much, even over a 24 hour period of grazing, would require a pasture with 37.5% fructan on a dry matter basis. Perennial ryegrass improved varieties growing under extreme conditions in areas of the world that are cool and rainy might have the potential to reach that level, at least transiently, but no grass in North America comes close. The average difference between WSC (sugars + fructans) and ESC (sugars) is only 2% in the Dairy One database. https://dairyone.com/…/forage…/feed-composition-library/ .

Crawford et al., 2007 fed 3 g/kg chickory fructan to ponies with and without a history of pasture laminitis. Despite a moderate drop in fecal pH from 6.89 to 6.18, there was no evidence of illness or laminitis, no increase in blood levels of fecal amines or D-lactate (bacterial) which would indicate a compromised colonic barrier. They concluded there is a threshold for fructan to have negative effects. For a pasture to reach that level of no effect the horse would have to consume a 15% fructan (dry matter basis) pasture for 24 hours. As above, that would be very high and is not the same thing as a pure bolus of chickory root fructan by stomach tube.

In 2006, Trieber et al., reported following a herd of 160 ponies on pasture and found a prelaminitic metabolic profile was defined on the basis of body condition, plasma triglyceride concentration, RISQI, and MIRG. (RISQI and MIRG are proxies for insulin sensitivity.) Meeting > or = 3 of these criteria differentiated prelaminitic from never-laminitic group ponies with a total predictive power of 78%. Onset of spring laminitis in the ponies at risk coincided with a flush of clover and increased pasture starch, not fructan.

Coleman et al., 2018 did a large epidemiological study of horses in North America and identified obesity, regional adiposity, and pre-existing endocrinopathy as risk factors. Menzies-Gow et al., 2017 followed 446 animals for a period of 3 years and monitored multiple factors to identify those which would be predictive of laminitis developing at pasture. They concluded: “Risk factors for future laminitis prior to disease occurrence include low plasma adiponectin and high serum basal insulin or insulin post-dexamethasone concentrations. “

Fructan-induced laminitis is a carbohydrate overload model with SIRS, endotoxemia, fever and diarrhea – none of which are seen with pasture laminitis. There is no question endocrinopathic laminitis is behind pasture laminitis. If fructan was the issue, all horses would be at risk; not only those identified as endocrinopathic.

Borer et al., 2016 demonstrated chicory fructan produces minimal changes in glucose or insulin which is not surprising considering fructan is not a sugar, and not absorbed. It is a storage form of carbohydrate composed of fructose chains but is no more a sugar than cellulose, which is a chain of glucose molecules. Mammalian digestive enzymes cannot break down these compounds, but bacteria in the hind gut can ferment them. They use the sugars they liberate for their own energy systems and produce volatile fatty acids or lactate as the end products.

It has been suggested that warm season grasses or legumes like alfalfa or clover would be safe since they do not contain fructan. This is not correct. In addition to Trieber’s 2006 study documenting the starch in clover pasture as a trigger (not fructan), Kagan et al., 2020 compared red and white clover samples collected in the morning and afternoon and found significant diurnal variation in starch content from morning to afternoon; red clover 13-51 g/kg; white clover 24-52 g/kg freeze-dried weight. At 10 kg/day dry matter intake, this represents a range of 130 to 520 grams of starch intake alone. This, combined with the WSC fraction which, given the lack of fructan, would be comprised of simple sugars, led the authors to conclude that grazing clover is not recommended for horses at risk of endocrinopathic (insulin-induced) laminitis.

For further in-depth discussion of fructan see Dr. Gustafson’s presentation from the 2021 NO Laminitis Conference, available to download free here https://www.e-junkie.com/ecom/gb.php?&i=1740628&cl=276648&c=cart&ejc=2&custom=card .

References

Borer KE, Bailey SR, Menzies-Gow NJ, Harris PA, Elliott J. Effect of feeding glucose, fructose, and inulin on blood glucose and insulin concentrations in normal ponies and those predisposed to laminitis. J Anim Sci. 2012 Sep;90(9):3003-11. doi: 10.2527/jas.2011-4236. PMID: 22966077.

Coleman MC, Belknap JK, Eades SC, Galantino-Homer HL, Hunt RJ, Geor RJ, McCue ME, McIlwraith CW, Moore RM, Peroni JF, Townsend HG, White NA, Cummings KJ, Ivanek-Miojevic R, Cohen ND. Case-control study of risk factors for pasture-and endocrinopathy-associated laminitis in North American horses. J Am Vet Med Assoc. 2018 Aug 15;253(4):470-478. doi:2460/javma.253.4.470. PMID: 30058970.

Crawford C, Sepulveda MF, Elliott J, Harris PA, Bailey SR. Dietary fructan carbohydrate increases amine production in the equine large intestine: implications for pasture-associated laminitis. J Anim Sci. 2007 Nov;85(11):2949-58. doi:10.2527/jas.2006-600. Epub 2007 Jun 25. PMID: 17591708.

Kagan IA, Anderson ML, Kramer KJ, Seman DH, Lawrence LM, Smith SR. Seasonal and Diurnal Variation in Water-Soluble Carbohydrate Concentrations of Repeatedly Defoliated Red and White Clovers in Central Kentucky. J Equine Vet Sci. 2020 Jan;84:102858. doi: 10.1016/j.jevs.2019.102858. Epub 2019 Nov 14. PMID: 31864464.

Menzies-Gow NJ, Harris PA, Elliott J. Prospective cohort study evaluating risk factors for the development of pasture-associated laminitis in the United Kingdom. Equine Vet J. 2017 May;49(3):300-306. doi: 10.1111/evj.12606. Epub 2016 Aug 25. PMID: 27363591.

Treiber KH, Kronfeld DS, Hess TM, Byrd BM, Splan RK, Staniar WB. Evaluation of genetic and metabolic predispositions and nutritional risk factors for pasture-associated laminitis in ponies. J Am Vet Med Assoc. 2006 May 15;228(10):1538-45. doi: 10.2460/javma.228.10.1538. PMID: 16677122.

van Eps AW, Pollitt CC. Equine laminitis induced with oligofructose. Equine Vet J. 2006 May;38(3):203-8. doi:10.2746/042516406776866327. PMID: 16706272