Choline is an essential nutrient linked to hepatic lipid metabolism in many animal species, including cats. The current study investigated the serum lipid profiles, serum liver enzymes, respiratory quotients and energy expenditures of overweight cats fed maintenance diets, in response to graded doses of supplemental dietary choline. Overweight (body condition score [BCS]:≥6/9) adult male neutered cats (n=14) were supplemented with five choline chloride doses for three-week periods, in a 5 x 5 Latin square design. Doses were based on individual body weight (BW) and the daily recommended allowance (RA) for choline (63mg/kg BW 0.67) according to the National Research Council. Doses were: control (no additional choline: 1.2 x RA, 77 mg/kg BW 0.67), 2 x RA (126mg/kg BW 0.67), 4 x RA (252mg/kg BW 0.67), 6 x RA (378mg/kg BW 0.67), and 8 x RA (504mg/kg BW 0.67). Choline was top-dressed over the commercial extruded cat food (3620mg choline/kg diet), fed once a day at maintenance energy requirements (130kcal/kgBW 0.4). Body weight and BCS were assessed weekly. Fasted blood samples were taken and indirect calorimetry was performed at the end of each three-week period. Serum was analyzed for cholesterol, high-density lipoprotein cholesterol (HDL-C), triglycerides, non-esterified fatty acids, glucose, creatinine, blood urea nitrogen (BUN), alkaline phosphatase (ALP) and alanine aminotransferase. Very low-density lipoprotein cholesterol (VLDL) and low-density lipoprotein cholesterol were calculated. Data was analyzed via SAS using proc GLIMMIX, with group and period as the random effects, and treatment as the fixed effect. Statistical significance was considered at P < 0.05. Body weight and BCS did not change (P > 0.05). Serum cholesterol, HDL-C, triglycerides, and VLDL increased with 6 x RA (P < 0.05). Serum ALP decreased with 8 x RA (P = 0.004). Choline at 4 x and 6 x RA decreased serum BUN (P = 0.006). Fed or fasted respiratory quotient and energy expenditure did not differ among dietary choline doses (P > 0.05). These results suggest that dietary choline supplementation at 6 x RA may increase hepatic fat mobilization through increased lipoprotein transport, and beneficially support hepatic health in overweight cats. Future studies that combine these results with existing knowledge of feline weight loss and hepatic lipidosis are warranted.

中文翻译：

---

维持能量需求喂养的超重成年猫的膳食胆碱与血脂、能量消耗和呼吸商之间的剂量反应关系

胆碱是与许多动物物种（包括猫）的肝脏脂质代谢相关的必需营养素。目前的研究调查了喂食维持饮食的超重猫的血清脂质谱、血清肝酶、呼吸商和能量消耗，以响应分级剂量的补充膳食胆碱。超重（身体状况评分 [BCS]：≥6/9）成年雄性绝育猫（n=14）在 5 x 5 拉丁方设计中补充五剂氯化胆碱，持续三周。根据国家研究委员会，剂量基于个体体重 (BW) 和胆碱的每日推荐摄入量 (RA) (63mg/kg BW 0.67)。剂量为：对照（无额外胆碱：1.2 x RA，77 mg/kg BW 0.67），2 x RA（126mg/kg BW 0.67），4 x RA（252mg/kg BW 0.67），6 x RA（378mg/kg体重 0.67), 和 8 x RA (504mg/kg BW 0.67)。胆碱是在商业挤压猫粮（3620mg 胆碱/kg 饮食）上的追肥，每天喂一次以维持能量需求（130kcal/kgBW 0.4）。每周评估体重和 BCS。采集空腹血样，并在每三周结束时进行间接量热法。分析血清中的胆固醇、高密度脂蛋白胆固醇 (HDL-C)、甘油三酯、非酯化脂肪酸、葡萄糖、肌酐、血尿素氮 (BUN)、碱性磷酸酶 (ALP) 和丙氨酸氨基转移酶。计算极低密度脂蛋白胆固醇（VLDL）和低密度脂蛋白胆固醇。使用proc GLIMMIX通过SAS分析数据，组和时期作为随机效应，治疗作为固定效应。在P＜1时考虑统计学显着性。0。05.体重和BCS没有变化（P＞0.05）。血清胆固醇、HDL-C、甘油三酯和 VLDL 随着 6 x RA 增加（P < 0.05）。血清 ALP 随 8 x RA 降低 (P = 0.004)。4 x 和 6 x RA 的胆碱降低了血清 BUN (P = 0.006)。进食或禁食的呼吸商和能量消耗在膳食胆碱剂量之间没有差异（P > 0.05）。这些结果表明，在 6 x RA 的膳食胆碱补充剂可通过增加脂蛋白转运来增加肝脏脂肪动员，并有益地支持超重猫的肝脏健康。未来的研究将这些结果与猫体重减轻和肝脂肪沉积的现有知识相结合是必要的。血清 ALP 随 8 x RA 降低 (P = 0.004)。4 x 和 6 x RA 的胆碱降低了血清 BUN (P = 0.006)。进食或禁食的呼吸商和能量消耗在膳食胆碱剂量之间没有差异（P > 0.05）。这些结果表明，在 6 x RA 的膳食胆碱补充剂可通过增加脂蛋白转运来增加肝脏脂肪动员，并有益地支持超重猫的肝脏健康。未来的研究将这些结果与猫体重减轻和肝脂肪沉积的现有知识相结合是必要的。血清 ALP 随 8 x RA 降低 (P = 0.004)。4 x 和 6 x RA 的胆碱降低了血清 BUN (P = 0.006)。进食或禁食的呼吸商和能量消耗在膳食胆碱剂量之间没有差异（P > 0.05）。这些结果表明，在 6 x RA 的膳食胆碱补充剂可通过增加脂蛋白转运来增加肝脏脂肪动员，并有益地支持超重猫的肝脏健康。未来的研究将这些结果与猫体重减轻和肝脂肪沉积的现有知识相结合是必要的。这些结果表明，在 6 x RA 的膳食胆碱补充剂可通过增加脂蛋白转运来增加肝脏脂肪动员，并有益地支持超重猫的肝脏健康。未来的研究将这些结果与猫体重减轻和肝脂肪沉积的现有知识相结合是必要的。这些结果表明，在 6 x RA 的膳食胆碱补充剂可通过增加脂蛋白转运来增加肝脏脂肪动员，并有益地支持超重猫的肝脏健康。未来的研究将这些结果与猫体重减轻和肝脂肪沉积的现有知识相结合是必要的。