Agriculture and Agri-Food Canada, Sherbrooke Research and Development Centre, 2000 College, Sherbrooke, QC, Canada, J1M 0C8; Département des Sciences Animales, Université Laval, 2425 rue de l'Agriculture, Québec, QC, Canada, G1V 0A6.
Department of Animal Science, Michigan State University, East Lansing 48824-1225.
J Dairy Sci. 2017 Oct;100(10):8165-8169. doi: 10.3168/jds.2017-13087. Epub 2017 Aug 2.
The effect of fat supplements (FS) providing different proportions of saturated (SFA) and unsaturated (UFA) fatty acids on supply, apparent ruminal synthesis (ARS), and duodenal flow (DF) of some B vitamins (thiamine, riboflavin, niacin, vitamin B, folates, and vitamin B) were evaluated in an experiment using 8 ruminally and duodenally cannulated lactating Holstein cows. The experiment was a replicated 4 × 4 Latin square design with 21-d treatment periods. The 4 treatments were a control diet without fatty acid supplement and 3 diets with 2.5% additional fatty acids from supplements containing (1) SFA, (2) an intermediate mixture of SFA and UFA, or (3) UFA. All diets were served as a total mixed ration once daily at 115% of the expected intake. B-vitamin concentrations were analyzed in feed and duodenal digesta. Apparent ruminal synthesis of each B vitamin was calculated as the DF minus the intake. B-vitamin concentrations were similar among the 4 treatments; consequently, daily intake of the vitamins followed the same pattern as dry matter intake. Adding FS decreased B-vitamin intakes (except vitamin B), as did increasing the proportion of UFA. Riboflavin and niacin DF and ARS, expressed as total daily amount or per unit of dry matter intake, were not affected by FS, but increasing the proportion of UFA decreased riboflavin and niacin DF and ARS. Fat supplements decreased DF of vitamin B, expressed either as total daily amount or per unit of dry matter intake. No treatment effects were observed on total daily folate DF and ARS. However, when expressed per unit of dry matter intake, folate DF and ARS were greater when cows were fed FS and they increased linearly with the proportion of UFA in the supplement. Inclusion of fat supplements into the dairy cow diet had a limited effect on the fate of most B vitamins in the rumen although increasing the proportion of UFA in the FS linearly decreased apparent synthesis of riboflavin and niacin in the rumen and the amounts of these vitamins reaching the small intestine.
在一项使用 8 头瘤胃和十二指肠瘘管泌乳荷斯坦奶牛的试验中，评估了脂肪补充剂（FS）提供不同比例饱和（SFA）和不饱和（UFA）脂肪酸对供应、表观瘤胃合成（ARS）和十二指肠流量（DF）的一些 B 族维生素（硫胺素、核黄素、烟酸、维生素 B、叶酸和维生素 B）的影响。该试验采用重复 4×4 拉丁方设计，处理期为 21 天。4 种处理分别为不含脂肪酸补充剂的对照日粮和 3 种日粮，添加 2.5%脂肪酸补充剂，补充剂中含有（1）SFA、（2）SFA 和 UFA 的中间混合物或（3）UFA。所有日粮均作为全混合日粮，每日喂给预计采食量的 115%。B 族维生素浓度在饲料和十二指肠食糜中进行分析。每种 B 维生素的表观瘤胃合成量均计算为 DF 减去摄入量。4 种处理间 B 族维生素浓度相似；因此，维生素的日摄入量与干物质摄入量呈相同模式。添加 FS 会降低 B 族维生素的摄入量（维生素 B 除外），增加 UFA 的比例也会降低 B 族维生素的摄入量。以总日量或单位干物质摄入量表示，FS 对核黄素和烟酸的 DF 和 ARS 没有影响，但增加 UFA 的比例会降低核黄素和烟酸的 DF 和 ARS。脂肪补充剂降低了维生素 B 的 DF，无论是以总日量还是单位干物质摄入量表示。FS 对总日叶酸 DF 和 ARS 没有影响。然而，当以单位干物质摄入量表示时，添加 FS 可使奶牛的叶酸 DF 和 ARS 增加，并且随着补充剂中 UFA 的比例线性增加。尽管增加 FS 中 UFA 的比例会使瘤胃中核黄素和烟酸的表观合成量线性降低，到达小肠的这些维生素量也会减少，但在奶牛日粮中添加脂肪补充剂对大多数 B 族维生素在瘤胃中的命运影响有限。
Zotero 插件