Use of sugar cane to feed lactating dairy goats

ABSTRACT The aim of the present study was to assess the effects of replacing corn silage with sugarcane in the diet of lactating Saanen goats and to determine their intake and digestibility of nutrients, ingestive behavior, milk yield and composition. The experimental diets were composed of increasing levels (0, 33, 66 and 100%) of substitution in dry matter (DM). Twelve multiparous Saanen goats, with an average body weight of 45.2kg, average milk yield of 3.0kg day-1, distributed in a triple latin square experimental design (4 × 4) were used. The dry matter intake (DMI) and other nutrients were estimated through the difference between the total nutrient in the food offered and its total in the leftovers. The DMI, crude protein, neutral detergent fiber (NDF) and total digestible nutrients were not influenced, but the apparent digestibility of DM and NDF decreased. Feeding time and feeding efficiency were not influenced, the rumination and total chewing times increased, and the leisure time decreased, both linearly. Milk yield was not influenced by substitution levels, but corrected milk yield to 3.5% fat decreased. Sugar cane represents a dietary alternative for goats with medium milk yield in critical periods of forage, since it does not change the consumption of DM and milk yield, even with the apparent declining digestibility of some nutrients, influencing the ingestive behavior of the animals.

摘要 本研究旨在评估日粮中以甘蔗替代玉米青贮对泌乳期萨能奶山羊的影响，并测定其养分采食与消化率、采食行为、产奶量及乳成分。试验日粮以干物质（DM）为基准设置梯度替代水平（0%、33%、66%和100%）。选用12头经产萨能奶山羊，平均体重45.2kg，平均日产奶量3.0kg，采用4×4三重拉丁方试验设计开展研究。干物质采食量（DMI）及其他养分摄入量通过饲粮总养分与剩余饲料总养分的差值估算。结果显示，干物质采食量、粗蛋白、中性洗涤纤维（NDF）及总可消化养分均未受替代水平的显著影响，但干物质与中性洗涤纤维的表观消化率显著降低。采食时长与采食效率无显著变化，反刍时长及总咀嚼时长呈线性增加，而休闲时长呈线性减少。产奶量未受替代水平影响，但乳脂率校正为3.5%的校正奶产量有所下降。在饲草供应紧张的关键时期，甘蔗可作为中等产奶量奶山羊的日粮替代原料，尽管部分养分的表观消化率有所下降，但该替代方式不会改变干物质采食量与产奶量，仅会对动物的采食行为产生影响。