In situ caecal degradation of roughages in horses

Abstract

-The present study was carried out to evaluate the in situ degradation of dry matter (DM), neutral detergent fiber (NDF) and crude protein (CP) in roughages by the in situ caecal digestion technique in horses. The roughages evaluated were: Lucerne hay (Medicago sativa), peanut (Arachis pintoi cv. Amarillo), desmodio(Desmodium ovalifolium), stylo (Stylosanthes guianensis cv. Mineirão), pigeon pea (Cajanus cajan), lime-yellow pea (Macrotyloma axillare) and coastcross hay (Cynodon dactylon cv. coastcross). The assay was conducted in a complete randomized design with seven roughages and three replications. One mare with a cannula fitted in the caecum was used, fed diet consisting of coastcross hay (80%) and concentrate (20%) at 2.0% BW, four times a day. Nylon 6.5 × 20 cm bags were used with 45 μ/pore, containing 5. Key Words: cannula, digestion, fiber, forage, legume Degradação cecal in situ de alimentos volumosos em equinos RESUMO -Objetivou-se avaliar a degradação da matéria seca (MS), fibra em detergente neutro (FDN) e proteína bruta de alimentos volumosos pela técnica da digestão cecal in situ em equinos. Avaliaram-se as forrageiras: feno de alfafa (Medicago sativa), amendoim forrageiro (Arachis pintoi cv. Amarillo), desmódio (Desmodium ovalifolium), estilosantes (Stylosanthes guianensis cv. Mineirão), guandu (Cajanus cajan), macrotiloma (Macrotyloma axillare) e feno de coastcross (Cynodon dactylon cv. coastcross). O ensaio teve duração de 35 dias e foi realizado em delineamento inteiramente casualizado com sete alimentos e três repetições. Utilizou-se uma égua fistulada no ceco, alimentada com dieta composta por feno de coastcross (80%) e concentrado (20%), fornecida quatro vezes ao dia em quantidade equivalente a 2% do peso vivo. No ceco, foram inseridos 3 a 4 sacos de náilon de porosidade 45 μ de 6,5 × 20 cm, contendo 5,2 g de MS/saco, nos tempos de 2, 4, 6, 8, 12, 24 e 48 horas de incubação. Os parâmetros de degradação da MS de todos os volumosos foram significativos. Não houve ajuste no modelo de degradação da PB e FDN do guandu. O amendoim, estilosantes e macrotiloma apresentaram maior fração potencialmente degradável da MS, com valores de 53, 46,5 e 40%, respectivamente, e os maiores valores da fração solúvel de 20, 21, 28,6%, além de elevadas taxas de degradação (10,36, 20,26 e 14,8%h -1 ). Nestes alimentos, também foram observadas as maiores taxas de degradação da FDN (9,1 e 11,3, 11,2%h -1 ), das frações potencialmente degradáveis (55, 51,8 e 47,2%) e as mais altas taxas de degradação da PB em 48 horas de incubação (87, 95, 94,8%, respectivamente). O amendoim forrageiro, o estilosantes e o macrotiloma apresentam potencial de uso nas dietas para equinos.Palavras-chave: cânula, digestão, fibra, forrageiras, leguminosa R. Bras.

Perennial peanut hay nutritive value

“…Tropical forages develop more in rainy season; consequently can contain higher concentration of fiber in this period. 5 These results of NDF (Table 2) are close to or lower than those 43.4; 46.8; 51.60; 52.50 and 55.50% achieved in A. pintoi with 60, 70, 100, and 42days, respectively 1,2,7,14,15 and to the 44% obtained in Arachis glabrata. 16 The mean values of ADF (Table 2) were lower than the 33.6, 28.1, 34.8, 35.8 and 30.7 described to forage legumes between 40 to 100days of age.…”

“…16 The mean values of ADF (Table 2) were lower than the 33.6, 28.1, 34.8, 35.8 and 30.7 described to forage legumes between 40 to 100days of age. 1,2,7,14,15 A. pintoi partially dehydrated and as silage presented ADF of 36.4 e 39%, respectively. 17 The ADF of 43.7, 32.9, 33.3 and 28.5% was described in forage legumes Medicago sativa, Desmodium ovalifolium, Stylosanthes guianensis and Cajanus cajan.…”

“…Increased deposition of cell wall also reduces the intake and digestibility of foodstuff, being undesirable. 15,18 So the lower content of ADF ( Table 2) could indicate a good nutritive value, because when the plant accumulates cell wall the cytoplasmic area is reduced. 15 The CP was higher (p≤0.05) in the C1 to C4 of A. pintoi hays ( Table 2).…”

Equine fecal inoculum optimization in in vitro fermentation assays of dehydrated roughage

“…Several studies with equine species were performed using in vivo or in situ methodologies to better understand the digestion process, which invariably involves kinetics of passage and nutrient degradation. Therefore, we have used the kinetic of passage (Van Weyenberg et al, 2006;Silva et al, 2014) and nutrient degradation information (Hyslop, 2006;Silva et al, 2010) to support the interpretations of the present study. Additionally, due to limitation to obtain fistulated animals for in vitro fermentation studies, a limiting factor nowadays, we had to use the information currently existing in the literature.…”

“…According to Silva et al (2010), who evaluated the in situ cecal degradation of nutrients in fistulated horses, a value of 34.3% NDFD of coastcross hay (Cynodon spp. cv coastcross) was observed after 48 h of incubation, which was greater than that observed in vitro in this study.…”