Hematological and biochemical parameters of lactating goats fed diets containing crude glycerin from biodiesel production from waste frying oil

ABSTRACT The aim of this study was to analyze the effects of the inclusion of crude glycerin (CG) from biodiesel production from waste frying oils on nutrients intake, hematological and biochemical parameters in lactating goats. Eight goats with 42.06±3.5kg of body weight were used, receiving diets containing 0, 7, 14 and 21% of CG based on total dietary DM. The experiment was carried out in a 4×4 double Latin square, with a duration of 80 days, four periods of 20 days, of which 15 days were for adaptation and five days for data collection. Blood samples were collected by puncture of the jugular vein. Dry matter, crude protein, and mineral matter intakes decreased linearly, while intake of ether extract increased quadratically. The concentrations of hematocrit, hemoglobin, red blood cells, and phosphorus reduced linearly. A quadratic tendency for serum calcium concentrations was observed. No effects were observed for concentrations of magnesium, glucose, total cholesterol, triglycerides, total plasmatic protein, albumin, globulins, urea, creatinine, aspartate aminotransferase, and alkaline phosphatase. It can be concluded that CG can be used in up to 7% of total dietary DM without promoting metabolic problems.

摘要
本研究旨在分析以废弃煎炸油为原料制备生物柴油过程中产生的粗甘油（crude glycerin, CG）对泌乳山羊营养物质摄入量、血液学及生化指标的影响。试验选用8只体重为42.06±3.5kg的泌乳山羊，饲喂以日粮干物质（dry matter, DM）占比计分别添加0、7%、14%和21% CG的试验日粮。本试验采用4×4复拉丁方设计，总时长80天，划分为4个周期，每个周期20天，其中前15天为适应期，后5天用于数据采集。通过颈静脉穿刺采集血液样本。结果显示，干物质、粗蛋白质及矿物质摄入量呈线性下降趋势，而乙醚提取物摄入量呈二次曲线变化趋势。红细胞比容（hematocrit）、血红蛋白（hemoglobin）、红细胞计数及磷浓度呈线性降低。血清钙浓度呈现二次曲线变化趋势。镁、葡萄糖、总胆固醇、甘油三酯、血浆总蛋白、白蛋白、球蛋白、尿素、肌酐、天冬氨酸氨基转移酶（aspartate aminotransferase）及碱性磷酸酶浓度未受显著影响。综上，粗甘油可在日粮干物质占比不超过7%的范围内添加，且不会引发代谢相关问题。