RESUMEN
This study aimed to compare the digestibility of tropical grasses by horses by the in vivo method using mobile nylon bags with the in vitro digestibility method using horse feces as a source of inoculum. Five horses were used in a 2 × 5 factorial design with randomized blocks featuring two methods (in vivo and in vitro) and five grasses: Tifton 85 hay (Cynodon spp.), sixweeks threeawn grass (Aristida adsencionis, Linn), Alexandergrass (Brachiaria plantaginea (Link) Hitchc.), capim-de-raiz (Chloris orthonoton, Doell), and Sabi grass (Urochloa mosambicensis). No difference (P>0.05) was found between the in vivo and in vitro methods regarding nutrient digestibility of Sabi grass and sixweeks threeawn. Tifton 85 was the only grass that showed differences (P<0.05) between the two methods concerning the apparent digestibility of all nutrients. Alexandergrass, Tifton 85, and capim-de-raiz exhibited the best digestibility of dry matter, neutral detergent fiber, acid detergent fiber, and organic matter by the mobile bag method compared to the in vitro method. Tifton 85 and capim-de-raiz had higher crude protein digestibility by the mobile bag method than by the in vitro method. The mean retention time of the mobile bags in the digestive tract of the horses was 43.69 h. The bags with samples of sixweeks threeawn and Sabi grass had shorter retention times than capim-de-raiz and Alexandergrass (P<0.0001). It is concluded that, for sixweeks threeawn and Sabi grass, digestibility in horses can be assessed using the in vitro method in place of the mobile nylon bag method.
RESUMEN
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.(AU)
Os óleos essenciais (EO), como o carvacrol, são descritos por representarem ampla gama de compostos principalmente voláteis de plantas aromáticas, com potencial antioxidante, antibacteriano, antifúngico, entre outras propriedades de interesse para a saúde animal, como a modulação do microbioma. Atualmente, os cavalos são submetidos a manejo intensivo, com uso excessivo de ração concentrada, o que pode causar graves distúrbios digestivos e metabólicos. Em cavalos, estudos com EO são limitados, mas o uso de óleo essencial de carvacrol (CEO) poderia promover benefícios na fermentação microbiana. O objetivo da presente pesquisa foi investigar o efeito de diferentes quantidades de óleo essencial de carvacrol, adicionadas à dieta de equinos, sobre a digestibilidade aparente total de nutrientes, o perfil microbiano por meio das fezes e a resposta sanguínea pós-prandial de glicose e insulina. Foram utilizados oito cavalos castrados, da raça Mini-Horse (42±6 meses), 135±15kg PV, alimentados na proporção de 60% concentrado e 40% feno de capim. Os tratamentos foram: 0, 100, 200 e 300ppm de CEO. A adição de CEO até 300ppm não influencia a digestibilidade aparente dos nutrientes e a resposta de glicose e insulina plasmática pós-prandial. O uso de EO demonstra manter a saúde digestiva fermentativa quando os cavalos são alimentados com dieta rica em concentrado.(AU)
