Department of Animal Sciences, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7602, South Africa.
J Anim Sci. 2011 Jul;89(7):2164-9. doi: 10.2527/jas.2010-3531. Epub 2011 Feb 4.
Eight Döhne Merino rams were used to quantify apparent absorption, distribution to tissues, and excretion of dietary melamine in sheep. Two batches of concentrate pellets were made; one (CON) contained corn gluten meal with no detectable melamine and the other (MEL) contained corn gluten meal that was previously found to be highly contaminated with melamine at 15,117 mg/kg. The MEL pellets contained 1,149 mg/kg of melamine. During a 10-d adaptation period, all the animals received a forage-based diet supplemented with 600 g/d of the CON pellets. This was followed by an 8-d collection period during which 6 of the animals received MEL pellets and 2 received CON pellets. Melamine intake of sheep that received MEL pellets was 0.69 g/d. Blood samples were taken before first ingestion of MEL pellets on d 1 and again on d 3, 6, and 8 of the collection period for melamine and serum creatinine analyses. Feces and urine were collected quantitatively over the 8 d for proximate and melamine analyses. All the animals were slaughtered at the end of the trial, and samples of the LM, liver, kidneys, and abdominal fat were taken for melamine analysis. Data of the 2 sheep that received CON pellets for the duration of the trial confirmed that no melamine was detected in any of the samples, and no statistical analyses were performed on these data. The apparent digestibility or efficiency of absorption of ingested melamine was 76.7%. Melamine was detected in the urine, blood, muscle (LM), and fat tissue of all the sheep that received MEL pellets. Serum melamine concentrations reached 5.4 mg/kg on d 8 of the collection period, and the meat (LM) contained 9.6 mg/kg of melamine. Calculations on the partitioning of ingested melamine suggested that urine is the major excretion route accounting for 53.2%, whereas feces accounted for 23.3% of ingested melamine. Approximately 3.5% of the ingested melamine was detected in muscle. It was concluded that ingested melamine is highly absorbable from the small intestine and that a pathway exists for the distribution of dietary melamine to meat.
八只道恩美利奴公羊被用于量化绵羊对膳食三聚氰胺的表观吸收、组织分布和排泄。制作了两批浓缩颗粒；一批（CON）含有玉米蛋白粉，未检出三聚氰胺，另一批（MEL）含有玉米蛋白粉，此前发现其高度污染三聚氰胺，含量为 15117 毫克/千克。MEL 颗粒含有 1149 毫克/千克三聚氰胺。在 10 天的适应期内，所有动物都接受了基于饲料的饮食，补充了 600 克/天的 CON 颗粒。随后是 8 天的收集期，其中 6 只动物接受了 MEL 颗粒，2 只接受了 CON 颗粒。接受 MEL 颗粒的绵羊的三聚氰胺摄入量为 0.69 克/天。在第 1 天首次摄入 MEL 颗粒前和收集期的第 3、6 和 8 天，采集血液样本进行三聚氰胺和血清肌酐分析。在 8 天内定量收集粪便和尿液，进行粪便和三聚氰胺分析。试验结束时，所有动物都被屠宰，采集 LM、肝脏、肾脏和腹部脂肪样本进行三聚氰胺分析。接受 CON 颗粒进行试验的 2 只绵羊的所有样本均未检测到三聚氰胺，因此对这些数据未进行统计分析。摄入的三聚氰胺的表观消化率或吸收率为 76.7%。接受 MEL 颗粒的所有绵羊的尿液、血液、肌肉（LM）和脂肪组织中均检测到三聚氰胺。收集期第 8 天，血清三聚氰胺浓度达到 5.4 毫克/千克，肌肉（LM）中含有 9.6 毫克/千克三聚氰胺。对摄入的三聚氰胺的分配计算表明，尿液是主要的排泄途径，占 53.2%，而粪便占摄入三聚氰胺的 23.3%。约 3.5%的摄入三聚氰胺在肌肉中被检测到。结论是，摄入的三聚氰胺从小肠高度吸收，并且存在将膳食三聚氰胺分配到肉中的途径。
