Han K J, Pitman W D, Chapple A
Louisiana State University Agricultural Center, Hill Farm Research Station, Homer, LA 71040, USA .
Louisiana State University Agricultural Center, Dept. of Experimental Statistics, Baton Rouge, LA 70803, USA .
Asian-Australas J Anim Sci. 2014 Oct;27(10):1436-42. doi: 10.5713/ajas.2014.14095.
Preservation of forage crops as silage offers opportunity to avoid the high risk of rain-damaged hay in the humid south-central USA. Recent developments with baled silage or baleage make silage a less expensive option than typical chopped silage. Silage has been important in the region primarily for dairy production, but baleage has become an option for the more extensive beef cattle industry in the region. Silage samples submitted to the Louisiana State University Agricultural Center Forage Quality Lab from 2006 through 2013 were assessed for dry matter (DM) and forage nutritive characteristics of chopped silage and baleage of the different forage types from commercial farms primarily in Louisiana and Mississippi. Of the 1,308 silage samples submitted, 1,065 were annual ryegrass (AR) with small grains (SG), the warm-season annual (WA) grasses, sorghums and pearl millet, and the warm-season perennial (WP) grasses, bermudagrass and bahiagrass, providing the remaining samples. Concentration of DM was used to indicate an effective ensiling opportunity, and AR silage was more frequently within the target DM range than was the WA forage group. The AR samples also indicated a high-quality forage with average crude protein (CP) of 130 g/kg and total digestible nutrient (TDN) near 600 g/kg. The cooler winter weather at harvest apparently complicated harvest of SG silage with chopped SG silage lower in both CP and TDN (104 and 553 g/kg, respectively) than either AR silage or baleage of SG (137 and 624 g/kg for CP and TDN, respectively). The hot, humid summer weather along with large stems and large forage quantities of the WA grasses and the inherently higher fiber concentration of WP grasses at harvest stage indicate that preservation of these forage types as silage will be challenging, although successful commercial silage samples of each forage type and preservation approach were included among samples of silages produced in the region.
将饲料作物制成青贮饲料，为美国中南部潮湿地区避免干草遭雨水损坏的高风险提供了契机。近期，打捆青贮饲料（即裹包青贮）的发展使青贮饲料成为比典型的切碎青贮饲料成本更低的选择。青贮饲料在该地区主要对乳制品生产很重要，但裹包青贮已成为该地区更广泛的肉牛产业的一种选择。2006年至2013年提交给路易斯安那州立大学农业中心饲料质量实验室的青贮饲料样本，针对主要来自路易斯安那州和密西西比州商业农场的不同饲料类型的切碎青贮饲料和裹包青贮饲料，评估了干物质（DM）和饲料营养特性。在提交的1308个青贮饲料样本中，1065个是一年生黑麦草（AR）与小粒谷物（SG）、暖季一年生（WA）禾本科植物、高粱和珍珠粟，其余样本为暖季多年生（WP）禾本科植物、狗牙根和巴哈雀稗。干物质浓度用于表明有效的青贮时机，与WA饲料组相比，AR青贮饲料更频繁地处于目标干物质范围内。AR样本还表明是一种优质饲料，平均粗蛋白（CP）为130克/千克，总可消化养分（TDN）接近600克/千克。收获时较凉爽的冬季天气显然使SG青贮饲料的收获变得复杂，切碎的SG青贮饲料的CP和TDN（分别为104克/千克和553克/千克）低于AR青贮饲料或SG的裹包青贮饲料（CP和TDN分别为137克/千克和624克/千克）。收获阶段炎热潮湿的夏季天气，以及WA禾本科植物的大茎和大量饲料，加上WP禾本科植物固有的较高纤维浓度，表明将这些饲料类型制成青贮饲料具有挑战性，尽管该地区生产的青贮饲料样本中包括了每种饲料类型和保存方法的成功商业青贮饲料样本。
