title: Nutritive value and anthelmintic effect of sainfoin pellets fed to experimentally infected growing rabbits.
abstract: Alternative strategies to synthetic chemical drugs are needed in livestock and are a key issue in organic farming today. This study aimed at examining the potentialities of sainfoin, a legume rich in condensed tannins, as a nutraceutical that combines nutritive and antiparasitic effects in rabbits. To test the effect of infection with a helminth (I: infected groups; NI: not infected groups) and the effect of substituting 40% of the alfalfa in a control diet (C) with sainfoin (diet S), four groups of 16 weaned rabbits were arranged according to a 2×2 bifactorial design. The sainfoin diet differed from the control by its tannin concentration (1.8% v. 1.0% tannic acid equivalent) and its ADL concentration (84 v. 43 g/kg). For each diet, 16 rabbits were infected with 2125 third-stage larvae of Trichostrongylus colubriformis. Growth, feed intake, feed conversion ratio and nematode faecal egg counts (FECs) were controlled for 6 weeks. A digestibility trial was performed. After necropsy, adult worms and eggs in utero per female were counted and egg-hatching rate calculated. Growth tended to be lower for S groups than for C groups (38.2 v. 39.5 g/day; P=0.06). Feed intake was higher for S groups compared with C groups (+5.2 g dry matter/day; P<0.01), as was the feed conversion ratio (3.2 v. 2.9; P<0.001), probably in relation to the dietary ADL level. Protein digestibility was reduced in S groups compared with C groups (-6.0 points; P<0.001), probably associated with the effect of the tannin concentration. Digestibility of hemicelluloses was reduced in infected rabbits compared with non-infected ones (-5 points; P=0.01). Using the substitution method, the digestible energy of dehydrated sainfoin pellets used as raw material was calculated at 11.12 MJ/kg and digestible proteins at 110 g/kg. The infection did not produce any clinical signs of digestive disorders. No differences were observed according to the diet, neither in the number of adult worms (972; P=0.50), the number of eggs in utero per female (14; P=0.95), nor FEC (400 eggs/g; P=0.57). In contrast, the rate of faecal egg hatching in the S group tended to be lower than in the control (58.3% v. 85.2%; P=0.08). In conclusion, sainfoin seems to fit nutritive requirements for rabbits, supplies a large quantity of fibre and particularly lignins, and limits the development of nematode eggs in faeces.
authors.affiliation: 1GenPhySE,Université de Toulouse,INRA,INPT,ENVT,31326 Castanet Tolosan,France.
authors.forename: H
authors.initials: H
authors.lastname: Legendre
authors.affiliation: 2UMR 1225 IHAP INRA/ENVT,23 Chemin des Capelles,31076 Toulouse,France.
authors.forename: H
authors.initials: H
authors.lastname: Hoste
authors.affiliation: 1GenPhySE,Université de Toulouse,INRA,INPT,ENVT,31326 Castanet Tolosan,France.
authors.forename: T
authors.initials: T
authors.lastname: Gidenne
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D000871:Anthelmintics / Q000494:pharmacology*; D004032:Diet / Q000662:veterinary; D019587:Dietary Supplements / Q000032:analysis*; D005243:Feces / Q000469:parasitology; D005260:Female; D000455:Medicago sativa / Q000737:chemistry; D009753:Nutritive Value; D010063:Ovum; D044945:Proanthocyanidins / Q000494:pharmacology*; D011817:Rabbits / Q000502:physiology*; D013634:Tannins / Q000494:pharmacology
chemical_list: D000871:Anthelmintics; D044945:Proanthocyanidins; D013634:Tannins
keywords: condensed tannin; nematode; nutraceutical; rabbit; sainfoin