The objective of this study was to determine the forage:concentrate ratio that would provide the greatest duodenal flow of @entity1474 in ewes supplemented with @entity1460 oil and to determine how diets differing in forage content affect flow of conjugated @entity4722 (CLA) and @entity26416 (18:1(trans-11)). Five mature ewes (66.5 +/- 12.8 kg) fitted with ruminal and duodenal cannulas were used in a 5 x 5 Latin square experiment. Diets were isonitrogenous and included bromegrass hay, cracked @entity4336 , @entity4336 gluten meal, @entity1133 , and limestone. Dietary fat was adjusted to 6% with @entity1460 oil. Five ratios of forage:concentrate (18.4:81.6, 32.2:67.8, 45.8:54.2, 59.4:40.6, and 72.9:27.1) were fed at 1.3% of BW daily in equal allotments at 0630 and 1830. After 14 d, @entity6214 (2.5 g) was dosed at each feeding for 7 d and ruminal, duodenal, and fecal collections were taken for the next 3 d. Duodenal flow of 18:0 increased linearly (P < 0.01) with dietary forage. Duodenal flow of 18:1(cis-9) and 18:2(cis-9,12) decreased (P < 0.001) but duodenal flow of 18:3(cis-9,12,15) increased (P < 0.01) with increased dietary forage. Biohydrogenation of dietary @entity1474 increased (P < 0.001) as dietary forage increased, which was concomitant with increased ruminal pH. Duodenal flow of 18:2(cis-9,trans-11) increased linearly (P < 0.01) with increased dietary forage but increased abruptly when forage was fed at 45.8%. Duodenal flow of the trans-10, cis-12 and cis-10, cis-12 CLA isomers decreased as dietary forage increased, but flow tended to increase on the highest-forage diet, resulting in both linear (P < 0.01) and quadratic (P < 0.01) effects. Duodenal flow of 18:1(trans-11) decreased from 8.28 g/d on the 18.4% forage diet to 5.47 g/d on the 59.4% forage diet then increased to 7.29 g/d on the highest-forage diet (quadratic, P < 0.1). Duodenal flow of 18:1(trans-11) was 27- to 69-fold greater than flow of CLA. We conclude that when ewes were fed a 6% crude fat diet duodenal flows of dietary @entity1718 changed incrementally as dietary forage was increased, whereas changes in flows of CLA isomers seemed to be more abrupt. Biohydrogenation changes were gradual with diet, suggesting a gradual shift in ruminal microbial populations with increasing forage. Finally, the highest-concentrate diet supported the greatest duodenal flows of dietary @entity1474 , as well as the highest flow of 18:1(trans-11).

Effect of forage:concentrate ratio on ruminal digestion and duodenal flow of XXXX in ewes.

@entity1718 :: ('MESH:D005227', 'Chemical') :: ['fatty acids'] @entity1133 :: ('MESH:D014508', 'Chemical') :: ['urea'] @entity6214 :: ('CHEBI:48242', 'Chemical') :: ['Cr2O3'] @entity4336 :: ('381124', 'Species') :: ['corn'] @entity1474 :: ('MESH:D005231', 'Chemical') :: ['unsaturated fatty acids'] @entity1460 :: ('3847', 'Species') :: ['soybean'] @entity26416 :: ('MESH:C050413', 'Chemical') :: ['trans-vaccenic acid'] @entity4722 :: ('MESH:D019787', 'Chemical') :: ['linoleic acid']
@entity1718 :: (MESH:D005227,Chemical) :: ['fatty acids']
