Total and Cecal Digestion of Roughages in Horses. / Digestão Total e Cecal de Alimentos Volumosos em Eqüinos.

AUTOR(ES)
DATA DE PUBLICAÇÃO

2007

RESUMO

This work aimed to evaluate digestibility and degradability of nutrients, and kinetics of passage in horses fed with forages using mobile bag and in situ cecal digestion. Two digestion trials were carried out and seven forages were used, lucerne (Medicago sativa), peanut (Arachis pintoi), Desmodium ovalifolium, Stylosanthes guianensis, Cajanus cajan, Macroptyloma axilares and coastcross (Cynodon dactylon cv. coastcross). Basal diet were composed by 80% hay and 20% concentrate. In first assay with mobile bags, five crossbreed horses were used with age varying from 17 to 27 years and average weight of 350 kg. A nylon cloth were used with 45μ pore size, and bags with dimensions of 7,5 x 2 cm, containing 510mg DM of sample/bag. These assay had 12 days of duration, and three for adaptation, five days for naso-gastric insertion of bags and four days for bags collection in feces. Randomized block design were used with seven treatments and five repetitions. Naso-gastric insertion of bags were made twice a day, at morning and afternoon, inserting 29 bags, and four bags of each feed and one blank. Transit time and excretion of bags were evaluated until 96h from insertion. Nutrients digestibility of forages were calculated through residues inside the bags. In situ assay was conducted with caecum fistulated horse, weight 210Kg. Bags with 20x 6,5cm were used with 5,2g of sample incubated inside caecum along times 0, 2, 4, 6, 8, 12, 24, and 48 hours. A randomized design was used with seven treatments and three repetitions during 30 days. Orskov &McDonald degradation model was used to fit the nutrients degradation curves. Nutrients digestibility of peanut, Desmodium and Macroptiloma were high than others roughages (P<0.05). Any difference were observed (P>0.05) among transit time, mediun retention time and passage rate, average values were 23.34, 48.63 and 2.07, respectively. Degradation rate were high to peanut, Desmodium and Macroptyloma. Peanut fiber and protein degradability is superior to others tropical legumes, and peanut presented high protein contents. Tropically forages peanut, Stylosanthes guianensis and Macroptyloma axilares presented potential to be use in horse diets.

ASSUNTO(S)

degradação sacos móveis. fibra in situ degradation zootecnia mobile bag. fiber

Documentos Relacionados