ABSTRACT The effects of treating sunflower seed (SS) and meal (SM), as well as of a mixture of both feeds (SSM; 45:55) with a solution of malic acid (1 M; 400 ml/kg feed) and heating for protection against ruminal degradation were studied. Four rumen-fistulated sheep were fed two mixed diets composed of oat hay and concentrate (40:60) and differing only in the concentrate, that contained either a mixture of untreated SS and SM (control diet) or treated SS and SM (MAH diet). A crossover design with two 24-d experimental periods was used, and each period included 10 d of diet adaptation, 9 d for in situ incubations of SS, SM and SSM, and 5 d for measuring ruminal fermentation characteristics and rumen emptying. From day 6 onwards a solution of (15NH4)2SO4 was continuously infused into the rumen of each sheep to label ruminal bacteria. Feeding the MAH diet did not affect either ruminal pH or concentrations of total volatile fatty acids and NH3-N, but decreased (p ≤ 0.01) the molar proportions of acetate and propionate and increased those of butyrate (p< 0.001). Organic matter and lipid contents of ruminal bacteria were lower whereas both N content and 15N enrichment were greater (p ≤ 0.05) in MAH-fed sheep. The in situ effective degradability (ED) of different fractions of SS, SM and SSM were calculated from the ruminal rates of particle comminution and passage, and values were corrected for microbial contamination. The MAH treatment decreased the ED of most fractions for all feeds and increased the supply of by-pass crude protein (CP) by 19.1% and 120% for SS and SM, respectively, and that of fat by 34% for SS. The MAH treatment also increased the in vitro intestinal digestibility of the by-pass CP for both SS (from 60.1% to 75.4%) and SM (from 83.2% to 91.0%). The simultaneous heating of both feeds (SSM) reinforced the protective effect of the MAH treatment and increased the by-pass CP without altering its intestinal digestibility, increasing the intestinally digested CP content by 16.8% compared with the value estimated from the results obtained for MAH-treated SS and SM incubated independently. These results indicate that the MAH treatment was effective to protect sunflower protein against rumen degradation and increased its intestinal digestibility.

中文翻译：

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饲喂葵花籽和抗瘤胃发酵粉对羊瘤胃发酵、细菌组成和原位降解的影响

摘要 用苹果酸溶液（1 M；400 ml/kg 饲料）和加热处理葵花籽 (SS) 和膳食 (SM) 以及两种饲料的混合物 (SSM；45:55) 的效果对防止瘤胃退化的保护进行了研究。四只瘤胃瘘的羊被喂食两种由燕麦干草和浓缩物（40:60）组成的混合饮食，不同之处仅在于浓缩物，其中包含未经处理的 SS 和 SM（对照饮食）或处理过的 SS 和 SM（MAH 饮食） ）。采用交叉设计，有两个 24 天的实验期，每个时期包括 10 天的饮食适应，9 天的 SS、SM 和 SSM 原位孵化，以及 5 天的瘤胃发酵特性和瘤胃排空测量。从第 6 天起，将 (15NH4)2SO4 溶液连续注入每只羊的瘤胃以标记瘤胃细菌。饲喂 MAH 日粮不影响瘤胃 pH 值或总挥发性脂肪酸和 NH3-N 的浓度，但会降低（p ≤ 0.01）乙酸盐和丙酸盐的摩尔比例并增加丁酸盐的摩尔比例（p < 0.001）。MAH 喂养的羊的瘤胃细菌的有机质和脂质含量较低，而 N 含量和 15N 富集均较高（p ≤ 0.05）。SS、SM 和 SSM 不同部分的原位有效降解率 (ED) 由瘤胃颗粒粉碎率和通过率计算，并针对微生物污染校正值。MAH 处理降低了所有饲料中大多数部分的 ED，并使 SS 和 SM 的旁路粗蛋白 (CP) 供应分别增加了 19.1% 和 120%，SS 的脂肪供应增加了 34%。MAH 处理还增加了 SS（从 60.1% 到 75.4%）和 SM（从 83.2% 到 91.0%）的旁路 CP 的体外肠道消化率。两种饲料的同时加热 (SSM) 增强了 MAH 处理的保护作用，并在不改变其肠道消化率的情况下增加了旁路 CP，与根据 MA​​H 结果估计的值相比，肠道消化的 CP 含量增加了 16.8% - 处理的 SS 和 SM 独立温育。这些结果表明，MAH 处理可有效保护向日葵蛋白免受瘤胃降解并增加其肠道消化率。两种饲料的同时加热 (SSM) 增强了 MAH 处理的保护作用，并在不改变其肠道消化率的情况下增加了旁路 CP，与根据 MA​​H 结果估计的值相比，肠道消化的 CP 含量增加了 16.8% - 处理的 SS 和 SM 独立温育。这些结果表明，MAH 处理可有效保护向日葵蛋白免受瘤胃降解并增加其肠道消化率。两种饲料的同时加热 (SSM) 加强了 MAH 处理的保护作用，并在不改变其肠道消化率的情况下增加了旁路 CP，与根据 MA​​H 结果估计的值相比，肠道消化的 CP 含量增加了 16.8% - 处理的 SS 和 SM 独立温育。这些结果表明，MAH 处理可有效保护向日葵蛋白免受瘤胃降解并增加其肠道消化率。