Effects of berry seed residues on ruminal fermentation, methane concentration, milk production, and fatty acid proportions in the rumen and milk of dairy cows

摘要

Strawberry (SB), black currant (BC), and raspberryseed (RB) residues were used in 3 experiments to studytheir effects on ruminal fermentation, methane concentration,and fatty acid (FA) proportions in the ruminalfluid and milk of dairy cows. Initially, a batch fermentationin vitro study (experiment 1) was performed toinvestigate the effects of the 3 berry residues on basicruminal fermentation parameters. Total volatile fattyacid concentrations, including acetate, propionate, andbutyrate, increased in the BC group compared withother treatments. Based on the preliminary in vitro results,2 consecutive in vivo experiments were conductedusing 4 Polish Holstein-Friesian cows fitted with rumencannulas (experiment 2) and 30 lactating Polish Holstein-Friesian dairy cows (experiment 3) in a replicated2 × 2 crossover design. Cows in both experiments receiveda partial mixed ration (PMR) in 2 variants: (1)a control diet of PMR + 2 kg of concentrate (control);(2) PMR + 2 kg of BC seed residues (BC). The BC dietdid not mitigate ruminal methane production. Ruminalfermentation (experiment 2) was not affected by the BCdiet; however, the concentrations of C18:1 trans-11 andC18:2 cis-9,trans-11 increased significantly by 91 and131%, respectively. Likewise, concentrations of totaltrans C18:1 and total monounsaturated FA in ruminalfluid were increased significantly by BC seed residues.In experiment 3, BC significantly increased milk fatC18:1 trans-11, C18:2 cis-9,trans-11, n-3, n-6, and polyunsaturatedFA concentrations without affecting milkproduction performance. In conclusion, the amount(2 kg/d) of BC used in this study did not adverselyaffect ruminal fermentation or milk production andcomposition. However, using BC increased proportionsof unsaturated FA and conjugated linoleic acid in milk.Although dietary BC did not exert a strong methaneinhibition effect, it could represent an inexpensive alternativeconcentrate to improve beneficial FA in milkwithout negative effects on rumen fermentation andproduction parameters in dairy cows. Incorporation ofberry seed residues in diets would be profitable economicallyand nutritionally for dairy cattle production.