title: Fatty acid composition of ruminal digesta and longissimus muscle from lambs fed silage mixtures including red clover, sainfoin, and timothy.
abstract: This work investigated the effects of feeding silage mixtures of a plant containing polyphenol oxidase (PPO; red clover [; RC]), a plant containing tannins (sainfoin [; SF]), and a grass species not containing these compounds (timothy [; T]) on ruminal and intramuscular (i.m.) fatty acids of lambs. Forty 4-mo-old castrated male Romane lambs, divided into 5 groups, received 1 of the following silages: 1) T (100%), 2) a binary mixture of timothy and tannin-containing sainfoin ( cv. Perly; 50:50 [T-SF]), 3) a binary mixture of timothy and PPO-containing red clover ( cv. Mervius; 50:50 [T-RC]), 4) a ternary mixture of timothy, sainfoin, and red clover containing both tannins and PPO (50:25:25, respectively [T-SF-RC]), and 5) a binary mixture of tannin-containing sainfoin and PPO-containing red clover (50:50 [SF-RC]). In the rumen digesta, the partial or total replacement of T with forage legumes was associated with greater concentrations of PUFA ( < 0.001) and 1esser concentrations of MUFA ( < 0.001). The inclusion of forage legumes in the silage favored the accumulation of 18:3 -3 ( < 0.001), with the greatest concentrations being observed in SF-RC. This latter diet also led to the greatest percentage of 18:2 -6 ( < 0.001). Forage legumes decreased the -11 18:1 to 30% of T in rumen digesta ( < 0.001). Forage legumes decreased the total concentration of branched-chain fatty acids in the rumen digesta (on average, -28%; < 0.001), this effect being less marked (-17%; = 0.014) in T-RC in comparison with T. The dietary treatment tended to affect the proportion of MUFA ( = 0.081) and of PUFA ( = 0.079) in the i.m. fat of the LM, respectively, at the highest and lowest numerical value in the T group. The sum of -3 fatty acids was less in the T and T-SF groups compared with the mixture of legumes without T (SF-RC; < 0.001 and < 0.008, respectively). The latter group had also a lesser -6-to--3 ratio than the T-SF group ( = 0.01). -11 18:1 was greater ( < 0.03) in lambs given T as the sole silage in comparison with lambs given T-RC, T-SF-RC, and SF-RC. Rumenic acid (-9 -11 CLA) was detected at a greater percentage in the LM from the animals fed the T silage compared with animals fed the T-SF-RC treatment ( = 0.004). Contrarily, -9 -12 -15 18:3 was found at a greater concentration in the muscle from lambs in the SF-RC treatment compared with lambs in the other treatments ( < 0.001). Furthermore, the T-RC group showed a greater proportion of α-linolenic acid than the T group ( = 0.03). In conclusion, the effects of the 2 active compounds (PPO and tannins) appear to be similar and additive. Moreover, a silage composed of a mixture of RC and SF is an excellent forage for growing lambs in terms of i.m. fatty acid composition.
authors.forename: L
authors.initials: L
authors.lastname: Campidonico
authors.forename: P G
authors.initials: PG
authors.lastname: Toral
authors.forename: A
authors.initials: A
authors.lastname: Priolo
authors.forename: G
authors.initials: G
authors.lastname: Luciano
authors.forename: B
authors.initials: B
authors.lastname: Valenti
authors.forename: G
authors.initials: G
authors.lastname: Hervás
authors.forename: P
authors.initials: P
authors.lastname: Frutos
authors.forename: G
authors.initials: G
authors.lastname: Copani
authors.forename: C
authors.initials: C
authors.lastname: Ginane
authors.forename: V
authors.initials: V
authors.lastname: Niderkorn
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D004032:Diet / Q000662:veterinary; D007887:Fabaceae / Q000737:chemistry*; D005227:Fatty Acids; D005260:Female; D005766:Gastrointestinal Contents / Q000737:chemistry*; D008297:Male; D018482:Muscle, Skeletal / Q000737:chemistry*; D031784:Phleum; D006109:Poaceae / Q000737:chemistry*; D012417:Rumen; D012756:Sheep; D012820:Silage / Q000032:analysis*; D013634:Tannins / Q000737:chemistry; D017962:alpha-Linolenic Acid
chemical_list: D005227:Fatty Acids; D013634:Tannins; D017962:alpha-Linolenic Acid