Han Ge, Yu Jie, He Jun, Zheng Ping, Mao Xiangbing, Yu Bing
Key Laboratory of Animal Disease-Resistant Nutrition and Feed of China Ministry of Agriculture and Rural Affairs, Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu 611130, China.
Animals (Basel). 2024 Mar 30;14(7):1057. doi: 10.3390/ani14071057.
Kitasamycin (KM), a broad-spectrum macrolide antibiotic, has implications for growth performance and residue in animals and humans. This study aimed to explore the effects of different KM doses on intramuscular fat accumulation, cecal microflora, and short-chain fatty acids (SCFAs) using a growing-finishing pig model. Forty-two pigs were divided into three groups: control, subtherapeutic KM (50 mg/kg, KM50), and therapeutic KM (200 mg/kg, KM200) diets over 8 weeks. KM50 led to increased back fat thickness, fat content in the longissimus dorsi muscle (LM), and elevated plasma total cholesterol (TC) levels ( < 0.05), supported by upregulated lipid synthesis gene expression (, , ) ( < 0.05) in the LM. KM50 altered cecal microflora, reducing spp. and spp. abundance, while increasing SCFA concentrations (acetic acid, propionic acid, total SCFAs) ( < 0.05). KM200 had minimal effects on intestinal weight and density, with increased apparent digestibility of nutrients. These findings highlight the dose-dependent impact of KM on intramuscular fat deposition. Subtherapeutic KM induced ectopic fat deposition, emphasizing potential risks in disease treatment for humans and animals.
吉他霉素（KM）是一种广谱大环内酯类抗生素，对动物和人类的生长性能及残留有影响。本研究旨在使用生长育肥猪模型探索不同剂量的KM对肌内脂肪积累、盲肠微生物群和短链脂肪酸（SCFAs）的影响。42头猪被分为三组：对照组、亚治疗剂量的KM（50毫克/千克，KM50）组和治疗剂量的KM（200毫克/千克，KM200）组，为期8周。KM50导致背部脂肪厚度增加、背最长肌（LM）脂肪含量增加以及血浆总胆固醇（TC）水平升高（P<0.05），这得到了LM中脂质合成基因表达上调（SREBP-1c、FAS、ACC）（P<0.05）的支持。KM50改变了盲肠微生物群，降低了大肠杆菌属和沙门氏菌属的丰度，同时增加了SCFA浓度（乙酸、丙酸、总SCFAs）（P<0.05）。KM200对肠道重量和密度影响最小，营养物质的表观消化率增加。这些发现突出了KM对肌内脂肪沉积的剂量依赖性影响。亚治疗剂量的KM诱导异位脂肪沉积，强调了对人类和动物疾病治疗的潜在风险。
