Cana-de-açúcar em substituição ao feno de capim-tifton 85 em rações para cabras Saanen / Sugar cane replacing grass hay tifton 85 in rations for Saanen goats

Avaliou-se o consumo e digestibilidade dos nutrientes em dietas para cabras da raça Saanen arranjadas em um quadrado latino 5x5, alimentadas com cana-de-açúcar em substituição (0, 25, 50, 75 e 100%) ao feno de capim-tifton 85. O experimento foi constituído de cinco períodos de 15 dias (10 dias para adaptação dos animais às dietas experimentais e 5 dias para coleta de dados e amostras). O consumo voluntário foi calculado pela diferença entre o ofertado e as sobras. Utilizou-se o óxido crômico para estimativa da produção de matéria seca fecal. A digestibilidade aparente da matéria seca, matéria orgânica, extrato etéreo e fibra em detergente neutro foi influenciada negativamente com a substituição, enquanto a digestibilidade da proteína e dos carboidratos não fibrosos não sofreu influência. O baixo consumo de matéria seca de rações com cana-de-açúcar torna-se um fator limitante para cabras de média a alta produção de leite.

The intake and digestibility of nutrients in the diets of Saanen goats arranged in a 5x5 Latin square design, fed with sugar cane replacement (0, 25, 50, 75 and 100%) hay Tifton 85 were evaluated. The experiment consisted of 5 periods of 15 days (10 days for animal adaptation to experimental diets and 5 days for data collection). The voluntary intake was calculated as the difference between the offered and leftovers. Digestibility chromic oxide was used to estimate the fecal dry matter production. The digestibility of dry matter, organic matter, ether extract and neutral detergent fiber was negatively influenced, whereas the digestibility of protein and non-fiber carbohydrates were not affected. The low dry matter intake of diets with sugar cane becomes a limiting factor for goats medium for high milk production.

Effects of Bermudagrass hay and soybean hulls inclusion on performance of sheep fed cactus-based diets.

The objective of this experiment was to determine the effects of replacing corn with soybean hulls (SH) or Bermudagrass tifton hay (TH) on performance of sheep fed cactus-based diets. Three ruminally fistulated sheep were used in a 3 x 3 Latin square experiment with 21-day periods. All diets contained 75% spineless cactus (dry matter basis, DM) and formulated to be isonitrogenous. Fiber source had no influence on nutrient intakes except for the intake of neutral detergent fiber (NDF) which was lower (p<0.05) for animals fed corn relative to those fed SH or TH. Time expended in rumination and total chewing time were higher (p<0.05) for animals fed TH than those fed SH or corn. In vivo nutrient digestibilities were similar for all dietary treatments and averaged 69.6%, 74.8%, 69.9%, and 61.8% for DM, organic matter, crude protein, and NDF, respectively. Feeding SH relative to TH and corn decreased ruminal pH (p<0.05) and increased concentration of total volatile fatty acids (p<0.05). However, ruminal NH3-N concentration was higher (p<0.05) for animal fed TH than for those fed SH or corn. Abdominal distension and ruminal biofilm production were greater (p<0.05) in animals fed corn or SH than in those fed TH. It was concluded that replacing corn with SH or TH up to 15% of the diet DM in a cactus-based diet had no effect on nutrient intakes or total tract nutrient utilization. Changes in ruminal fermentation parameters reflected differences in ruminal degradability between the two fiber sources. Bermudagrass tifton hay was more effective than SH in reducing the risk of bloat associated with feeding high levels of spineless cactus to ruminants.