Use of essential oil on digestive health and blood parameters of maintenance horses

ABSTRACT Essential oils (EO) such as carvacrol represent a wide range of mainly volatile aromatic plant compounds which hold antioxidant, antibacterial and antifungal potential, in addition to other properties of interest to animal health, such as the ability to modulate the microbiome. Current horse care commonly involves an intensive management system with an excessive use of concentrated feed, which can lead to severe digestive and metabolic disorders. Studies with EO in horses are limited, but the use of carvacrol essential oil (CEO) can promote benefits in microbial fermentation. The objective was to investigate the effect of different quantities of CEO on the apparent total digestibility of nutrients, microbial profile in the feces and postprandial blood glucose and insulin response when added to the equine diet. Eight Mini-Horse geldings were used (42±6 months; 135±15 kg BW) and fed with a proportion of 60% concentrate and 40% grass hay. The treatments were: 0, 100, 200 and 300 ppm of CEO. The addition of CEO up to 300 ppm did not influence the apparent digestibility of nutrients or the postprandial plasma glucose and insulin response. The use of CEO maintained the fermentative digestive health of horses fed with concentrate diets.

摘要：香精油（EO）是一类主要由挥发性芳香植物化合物构成的物质，香芹酚（carvacrol）为其典型代表，该类物质兼具抗氧化、抗菌与抗真菌活性，同时具备动物健康领域备受关注的其他特性，例如调节肠道微生物群的能力。当前马匹饲养普遍采用集约化管理模式，且过度使用浓缩饲料，这极易引发严重的消化及代谢紊乱。目前针对马匹应用香精油的研究较为有限，但香芹酚精油（CEO）可有效改善微生物发酵效果。本研究旨在探究在马匹日粮中添加不同剂量的CEO，对养分表观全肠道消化率、粪便微生物群落组成，以及餐后血糖与胰岛素应答的影响。试验选用8匹阉割迷你马，年龄为42±6月龄，体重135±15 kg（BW），日粮配比为60%浓缩饲料与40%禾本科干草。试验设置4个处理组，分别添加0、100、200及300 ppm的CEO。结果显示，当日粮中CEO添加量不超过300 ppm时，不会对养分表观消化率、餐后血浆血糖及胰岛素应答产生显著影响；添加CEO可维持饲喂浓缩饲料马匹的发酵型消化健康。