This study aimed to determine the importance of adding organic acids in mulard ducks feeding programs. Hence, the quality of anaerobically fermented high-moisture feed, in addition to, performance, carcass traits, intestinal histology and the most common gastrointestinal pathogens were evaluated in response to different levels of organic acids (OAs). Mulard ducklings (n = 400) were randomly allocated into four groups (10 replicates each), and four fermented diets were provided randomly as follows: control fermented diet (without OAs) or fermented diets supplemented with 0.5, 1 or 2% OAs blend during the starter and finisher periods. Also, different fermentation periods were tested (7, 14, 21 and 28 days). The results showed that, OAs addition to fermented diets decreased fermentation-related nutrient loss and significantly decreased population counts of studied microorganisms. Moreover, the concentrations of lactic and propionic acids were significantly increased, and butyric acid was decreased with increasing OAs levels. The highest body weight gain was observed in the 2% OAs group. Feed utilization was improved in the groups fed on 1% and 2% OAs, when compared to the control group. In addition, OAs supplementation to the fermented diets showed a significant positive outcome on carcass weight, breast and thigh yield. Crude protein content was also increased in breast and thigh, while, fat was decreased in breast meat. Increasing OAs level showed an inhibitory effect on cecal pathogenic microbes (E. coli, Salmonella, Campylobacter and Clostridium perfringens), and increased the beneficial bacteria population (Lactobacilli and Bifidobacterium). Intestinal length and intestinal villi height seen by light and electron microscopy (both account for the area for absorption) were increased by OAs in a dose dependent manner, leading to improved nutrient digestibility (also, the best results in this study were obtained in the 2% OAs group). Accordingly, our results demonstrated that addition of OAs to high-moisture fermented feed led to improving its quality, also, it improved intestinal histology (on the villus and cellular levels) and decreased enteric pathogenic microbes and increased beneficial bacteria, all of which were positively reflected in duckling's performance and meat quality

这项研究旨在确定在mul鸭饲养计划中添加有机酸的重要性。因此，除了对性能，car体性状，肠道组织学和最常见的胃肠道病原体进行响应以外，还对厌氧发酵的高水分饲料的质量进行了评估，以应对不同水平的有机酸（OAs）。穆拉德小鸭（n = 400）被随机分为四组（每组10个重复），并按以下方式随机提供四种发酵饮食：对照发酵饮食（无OAs）或在开始和结束过程中添加0.5％，1％或2％OAs混合的发酵饮食期。同样，测试了不同的发酵期（7、14、21和28天）。结果表明，在发酵饮食中添加OA可以减少与发酵有关的营养损失，并显着减少所研究微生物的种群数量。此外，随着OAs水平的增加，乳酸和丙酸的浓度显着增加，而丁酸则降低。在2％OAs组中观察到最高的体重增加。与对照组相比，以1％和2％OA喂养的组的饲料利用率有所提高。此外，在发酵饮食中添加OAs对car体重量，乳房和大腿产量显示出显着的积极结果。乳房和大腿中的粗蛋白质含量也增加，而乳房肉中的脂肪减少。OAs水平升高显示对盲肠病原微生物具有抑制作用（大肠杆菌，沙门氏菌，弯曲杆菌和产气荚膜梭状芽胞杆菌），并增加了有益细菌的数量（乳酸杆菌和双歧杆菌））。光和电子显微镜观察到的肠长和肠绒毛高度（均考虑了吸收面积）被OAs以剂量依赖的方式增加，从而提高了养分的消化率（同样，在本研究中获得了最好的结果2 ％OAs组）。因此，我们的结果表明，在高水分发酵饲料中添加OA不仅可以提高其质量，而且还可以改善肠道组织学（在绒毛和细胞水平上），并减少肠道病原微生物和增加有益细菌，所有这些都是积极的反映在小鸭的性能和肉质上