The aim of this study was to investigate the effects of the inclusion of chopped straw into a diet with pelleted starter feed on starter intake, growth performance, fermentation and blood metabolites of dairy calves during the pre- and post-weaning periods. Forty-four Holstein-Friesian female dairy calves were randomly assigned to four treatments: control (CON, starter without straw; n = 11), low straw (LS, starter feed containing 10% dry matter basis straw; n = 11), medium straw (MS, starter feed containing 15% dry matter basis straw; n = 11) and high straw (HS, starter feed containing 20% dry matter basis straw; n = 11). Starter intake and total dry matter intake were recorded daily, and bodyweight weekly until 84 days of age. The highest starter intake and total dry matter intake were noted in the LS and MS treatments during the post-weaning, and overall experiment periods. Also, the average daily gain was greater during the pre-weaning period for LS and MS than HS. Increasing chopped straw content in the starter feeds from 0% to 15% increased ruminal pH, especially at day 28, and molar concentration of acetate, and decreased concentrations of total volatile fatty acids and propionate throughout the trial. Concentrations of butyrate in the rumen were lower at day 28, and higher at day 56 and 84 in straw-supplemented calves compared to the CON treatment. Increasing chopped straw content in the starters feeds from 0% to 15% increased the total counts of bacteria and protozoa, but then this counts decreased with the content of 20% chopped straw. In conclusion, the inclusion of chopped triticale straw from 10% to 15% in the diet with pelleted starter feed can improve performance, and rumen fermentation in calves; however, increasing the dietary inclusion of straw to 20% can negatively affect growth performance.

中文翻译：

---

奶牛日粮中添加秸秆对断奶前后生长性能、瘤胃发酵和血液代谢物的影响

本研究的目的是研究在断奶前和断奶后将切碎的秸秆加入到含有颗粒状开食料的日粮中对奶牛的开食料摄入、生长性能、发酵和血液代谢物的影响。将 44 头荷斯坦-弗里斯兰雌性奶牛犊随机分配到四种处理组：对照（CON，不带稻草的起子；n  = 11）、低稻草（LS，含 10% 干物质基础稻草的起子饲料；n  = 11）、中等秸秆（MS，起始饲料含有 15% 干物质基础秸秆；n  = 11）和高秸秆（HS，起始饲料含有 20% 干物质基础秸秆；n 将起始饲料中的切碎秸秆含量从 0% 增加到 15% 会增加细菌和原生动物的总计数，但随后随着 20% 切碎秸秆的含量而减少。总之，在颗粒状发酵饲料的日粮中添加 10% 至 15% 的碎黑小麦秸秆可以提高小牛的生产性能和瘤胃发酵；然而，将秸秆的日粮添加量增加到 20% 会对生长性能产生负面影响。