Godfrey Hannah, Ribeiro Érico de Mello, Verton-Shaw Shoshana, Shoveller Anna Kate, Kostiuk Darcia, Kelly Janelle, Saunders Blades Jennifer, Verbrugghe Adronie
Department of Biomedical Sciences, University of Guelph, Guelph, ON, Canada.
Department of Clinical Studies, University of Guelph, Guelph, ON, Canada.
Front Vet Sci. 2025 May 19;12:1588330. doi: 10.3389/fvets.2025.1588330. eCollection 2025.
High consumption of dietary carbohydrates (nitrogen-free extract, NFE) in extruded dry foods is postulated as a risk factor for feline obesity, though evidence is limited. This study utilized a three-test diet approach to isolate the effect of each macronutrient on body composition, voluntary physical activity, and serum satiety hormone response in lean and obese cats.
A pairwise isoenergetic reduction as % metabolizable energy (ME, using modified Atwater) of dietary macronutrients created a low-protein (LP; protein = 28%, fat = 40%, NFE = 32%ME), low-fat (LF; protein = 40%, fat = 30%, NFE = 30%ME), and low-carbohydrate (LC; protein = 36%, fat = 41%, NFE = 23%ME) diet. Cats (lean = 9; obese = 9) were fed the LP, LF, or LC diet to maintain body weight for 4-weeks in a 3 × 3 Latin square design. Voluntary physical activity was measured from day 15-21. On day 23, body composition was assessed by dual energy x-ray absorptiometry. On day 24, blood was collected for fasted and 6-h post-prandial serum satiety hormones. Data were analysed using SAS Studio via proc. GLIMMIX with significance set at < 0.05.
Greater lean soft tissue mass was observed for LF compared to LP and LC ( = 0.0101) though no other changes in body composition were observed. Daily food intake (g/d) differed among diets (LP: 56.14 ± 0.56; LF: 59.52 ± 0.59; LC: 56.50 ± 0.56; = 0.0003) though energy intake (kcal/d) was similar (LP: 218.47 ± 2.32; LF: 220.42 ± 2.34; LC: 225.37 ± 2.39; = 0.1076). Voluntary physical activity was similar for lean and obese cats ( = 0.4025). LP cats exhibited less physical activity during dark hours compared to LF and LC ( = 0.0155). No body condition effect was observed for serum leptin or ghrelin ( = 0.6243 and = 0.6747). Obese cats on LP exhibited a lower serum leptin iAUC compared to obese cats on LC (P = 0.0093). Post-prandial serum ghrelin decreased in all cats whereas serum peptide YY (PYY) increased at 1-, 2-, and 3-h post-prandial (P = 0.0094 and P = 0.0050). Serum ghrelin was lower at 6-h post-prandial (P = 0.0030) and serum PYY was greater at 1-h post-prandial (P = 0.0086) for LC.
Overall, the LP, LF, and LC diets were not associated with differences in most parameters, supporting that cats are metabolically flexible if nutrient requirements are met. There may be benefits regarding satiety hormone responses to a LC diet in cats though more research is required.
尽管证据有限，但推测挤压干燥食品中高碳水化合物（无氮浸出物，NFE）的摄入是猫肥胖的一个风险因素。本研究采用三种试验饮食方法，以分离每种宏量营养素对瘦猫和肥胖猫身体成分、自主身体活动及血清饱腹感激素反应的影响。
通过按膳食宏量营养素占可代谢能量（ME，使用改良阿特沃特法）的百分比进行成对等能量减少，配制出低蛋白（LP；蛋白质=28%，脂肪=40%，NFE=32%ME）、低脂肪（LF；蛋白质=40%，脂肪=30%，NFE=30%ME）和低碳水化合物（LC；蛋白质=36%，脂肪=41%，NFE=23%ME）饮食。猫（瘦猫=9只；肥胖猫=9只）采用3×3拉丁方设计，分别喂食LP、LF或LC饮食以维持体重4周。从第天15至21天测量自主身体活动。在第23天，通过双能X线吸收法评估身体成分。在第24天，采集血液以检测空腹和餐后6小时的血清饱腹感激素。数据使用SAS Studio通过proc. GLIMMIX进行分析，显著性设定为<0.05。
与LP和LC相比，LF组的瘦软组织质量更高（=0.0101），但未观察到身体成分的其他变化。不同饮食组的每日食物摄入量（克/天）存在差异（LP：56.14±0.56；LF：59.52±0.59；LC：56.50±0.56；=0.0003），但能量摄入量（千卡/天）相似（LP：218.47±2.32；LF：220.42±2.34；LC：225.37±2.39；=0.1076）。瘦猫和肥胖猫的自主身体活动相似（=0.4025）。与LF和LC相比，LP组猫在黑暗时段的身体活动较少（=0.0155）。未观察到血清瘦素或胃饥饿素的身体状况效应（=0.6243和=0.6747）。与LC组肥胖猫相比，LP组肥胖猫的血清瘦素iAUC较低（P=0.0093）。所有猫餐后血清胃饥饿素均下降，而餐后1小时、2小时和3小时血清肽YY（PYY）升高（P=0.0094和P=0.0050）。LC组猫餐后6小时血清胃饥饿素较低（P=0.0030），餐后1小时血清PYY较高（P=0.0086）。
总体而言，LP、LF和LC饮食在大多数参数上未显示出差异，这表明如果满足营养需求，猫在代谢上具有灵活性。尽管需要更多研究，但猫对LC饮食的饱腹感激素反应可能存在益处。
