LEAF - Linking Landscape, Environment, Agriculture and Food Research Center, Associate Laboratory TERRA, Instituto Superior de Agronomia, Universidade de Lisboa, Lisboa, Portugal.
CIISA - Centre for Interdisciplinary Research in Animal Health, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisboa, Portugal.
J Anim Physiol Anim Nutr (Berl). 2024 Nov;108(6):1624-1640. doi: 10.1111/jpn.14005. Epub 2024 Jun 18.
Ulva lactuca, a green seaweed, may be an alternative source of nutrients and bioactive compounds for weaned piglets. However, it has a recalcitrant cell wall rich in a sulphated polysaccharide - ulvan - that is indigestible to monogastrics. The objective of this study was to evaluate the effect of dietary incorporation of 7% U. lactuca, combined with carbohydrases supplementation (commercial carbohydrase mixture or recombinant ulvan lyase), on growth performance, nutrient digestibility and gut health parameters (morphology and microbiota) of weaned piglets. The experiment was conducted over 14 days using 40 weaned piglets randomly allocated to one of four experimental diets: a control diet based on wheat-maize-soybean meal, a diet with 7% U. lactuca replacing the control diet (UL), a diet with UL supplemented with 0.005% Rovabio® Excel AP, and a diet with UL supplemented with 0.01% of a recombinant ulvan lyase. The dietary treatments had no major effects on growth performance, nitrogen balance and gut content variables, as well as histological measurements. Contrarily, dry matter and organic matter digestibility decreased with dietary seaweed inclusion, while hemicellulose digestibility increased, suggesting a high fermentability of this cell wall fraction independently of carbohydrases supplementation. Some beneficial microbial populations increased as a consequence of enzymatic supplementation (e.g., Prevotella), while seaweed diets as a whole led to an increased abundance of Shuttleworthia, Anaeroplasma and Lachnospiraceae_NK3A20_group, all related with a healthier gut. It also decreased Lactobacillus when compared to controls, which is possibly related to increased bioavailability of seaweed zinc. This study indicates that, under these experimental conditions, up to 7% dietary U. lactuca has no detrimental effect on piglet growth, despite decreasing acid detergent fibre digestibility. Carbohydrases supplementation of Ulva diets is not required at this incorporation level.
绿藻，一种绿色海藻，可能是断奶仔猪营养和生物活性化合物的替代来源。然而，它的细胞壁富含一种难以消化的硫酸多糖 - 岩藻聚糖 - 这种多糖对于单胃动物是不可消化的。本研究旨在评估日粮中添加 7%的绿藻，结合添加碳水化合物酶（商业碳水化合物酶混合物或重组岩藻聚糖裂解酶）对断奶仔猪生长性能、养分消化率和肠道健康参数（形态和微生物群）的影响。该实验在 14 天内使用 40 头断奶仔猪进行，随机分配到四种实验日粮之一：基于小麦-玉米-豆粕的对照日粮、用对照日粮替代的 7%绿藻日粮（UL）、用 0.005% Rovabio® Excel AP 补充的 UL 日粮和用 0.01%重组岩藻聚糖裂解酶补充的 UL 日粮。日粮处理对生长性能、氮平衡和肠道内容物变量以及组织学测量没有重大影响。相反，随着日粮中海藻的添加，干物质和有机物消化率降低，而半纤维素消化率增加，这表明细胞壁部分具有较高的发酵性，而与碳水化合物酶的添加无关。一些有益的微生物群体因酶的补充而增加（例如，普雷沃氏菌），而海藻日粮整体上导致 Shuttleworthia、Anaeroplasma 和 Lachnospiraceae_NK3A20_group 的丰度增加，所有这些都与更健康的肠道有关。与对照组相比，海藻日粮还降低了乳酸杆菌的丰度，这可能与海藻锌的生物利用度增加有关。本研究表明，在这些实验条件下，日粮中添加高达 7%的绿藻对仔猪生长没有不利影响，尽管降低了酸性洗涤剂纤维的消化率。在这种添加水平下，不需要对 Ulva 日粮进行碳水化合物酶的补充。
