Pulsipher G D, Galyean M L, Hallford D M, Smith G S, Kiehl D E
Department of Animal and Range Sciences, New Mexico State University, Las Cruces 88003.
J Anim Sci. 1994 Jun;72(6):1561-9. doi: 10.2527/1994.7261561x.
To determine which clay minerals have the potential to bind swainsonine, an in vitro screening procedure was conducted. Twenty compounds were screened in one replicated in vitro trial. A commercially available bentonite bound approximately 10% swainsonine and was chosen for use in a subsequent lamb feeding trial. Twenty fine-wool lambs (30.5 +/- .7 kg) were assigned to one of five treatments (four lambs/treatment). Treatments included 1) positive control, 100% sorghum sudangrass hay, 2) 85% sorghum sudangrass:15% locoweed (Oxytropis sericea, 430 ppm [DM basis] of swainsonine) +0 g of bentonite, 3) Treatment 2 + 14 g of bentonite, 4) Treatment 2 + 28 g of bentonite, and 5) Treatment 2 + 42 g of bentonite. Lambs were fed the experimental diets for 35 d and were then fed the positive control diet for an additional 21 d. Lambs were weighted and blood was collected via jugular venipuncture weekly from d 0 through 56. On d 35, additional blood samples were collected 1, 2, 4, and 8 h after feeding. Weekly blood samples were analyzed for serum clinical chemistry profiles, and additional blood samples collected on d 35 were analyzed for serum metabolic hormones and serum swainsonine concentrations. Within 1 wk, serum alkaline phosphatase and glutamic oxaloacetic transaminase activities increased markedly (P < .05) in lambs fed locoweed. Serum insulin, growth hormone, and prolactin concentrations were not affected by feeding locoweed, but serum triiodothyronine and thyroxine concentrations were decreased by approximately 50% (P < .05) in lambs fed locoweed.(ABSTRACT TRUNCATED AT 250 WORDS)
为了确定哪些粘土矿物有可能结合苦马豆素，进行了一项体外筛选程序。在一次重复的体外试验中对20种化合物进行了筛选。一种市售膨润土结合了约10%的苦马豆素，并被选用于随后的羔羊饲养试验。20只细毛羔羊（30.5±0.7千克）被分配到五种处理之一（每种处理4只羔羊）。处理包括：1）阳性对照，100%苏丹草干草；2）85%苏丹草：15%疯草（绢毛棘豆，苦马豆素含量430 ppm[干物质基础]）+0克膨润土；3）处理2+14克膨润土；4）处理2+28克膨润土；5）处理2+42克膨润土。羔羊饲喂实验日粮35天，然后再饲喂阳性对照日粮21天。从第0天到第56天，每周通过颈静脉穿刺对羔羊称重并采集血液。在第35天，饲喂后1、2、4和8小时采集额外的血样。每周的血样用于分析血清临床化学指标，第35天采集的额外血样用于分析血清代谢激素和血清苦马豆素浓度。在1周内‘，饲喂疯草的羔羊血清碱性磷酸酶和谷草转氨酶活性显著增加（P<0.05）。饲喂疯草对血清胰岛素、生长激素和催乳素浓度没有影响，但饲喂疯草的羔羊血清三碘甲状腺原氨酸和甲状腺素浓度降低了约50%（P<0.05）。（摘要截短至250字）
