Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G61 1QH, UK.
Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow G61 1QH, UK.
Animal. 2022 Mar;16(3):100462. doi: 10.1016/j.animal.2022.100462. Epub 2022 Feb 15.
High levels of supplementation with cereal increases production rates in cattle but can increase incidence of disease, ranging from mild indigestion to acute ruminal acidosis and death. Therefore, there is motivation to determine biological markers which can be used to identify whether animals have been, or are being fed, sufficient or excessive cereals. This study aimed to describe light microscopic findings from animals being fed diverse dietary cereal proportions and to test the performance of a novel rumen epithelial scoring system. Rumen wall tissue samples were obtained from the abattoir from 195 cattle from 11 Scottish farms and processed for histological examination. Light microscopic examination was used to characterise ruminal epithelial response to dietary challenge. Secondary objectives included describing the distribution of immune-related cells in bovine ruminal epithelium and assessing the use of a modified Elastin Martius Scarlet Blue stain (EMSB) for histological examination of the rumen epithelium. Cells staining positive for cluster of differentiation 3 were distributed mainly in the lower layers of the stratum basale and were found in higher densities in animals offered lower cereal proportion diets. Cells staining positive for major histocompatibility complex class 2 (MHCII) were most common in perivascular locations and in the junction between the lower stratum basale and the propria-submucosa. The density of MHCII positive staining cells was higher in animals on lower cereal diets. The level of supplementation with cereal was also associated with the thickness of the stratum corneum (SCT) and stratum granulosum (SGT), the integrity of the stratum corneum and sloughing of cornified cells. There were no advantages in using EMSB stain over haematoxylin and eosin (H&E) in this scoring system. We concluded that a scoring system that included only SCT, SGT and a measure of the loss of appearance of intercellular space allowed differentiation of groups of animals according to the level of cereal supplementation.
高比例的谷物补充会提高牛的生产速度，但也会增加疾病的发生率，从轻度消化不良到急性瘤胃酸中毒和死亡不等。因此，有必要确定生物标志物，以确定动物是否已经或正在摄入足够或过量的谷物。本研究旨在描述不同日粮谷物比例喂养动物的光镜下发现，并测试一种新型瘤胃上皮评分系统的性能。从 11 个苏格兰农场的 195 头牛的屠宰场获得瘤胃壁组织样本，并进行组织学检查。光镜检查用于描述瘤胃上皮对饮食挑战的反应。次要目标包括描述牛瘤胃上皮中免疫相关细胞的分布，并评估改良的弹性纤维马蒂斯猩红蓝染色（EMSB）在瘤胃上皮组织学检查中的应用。对分化群 3 染色阳性的细胞主要分布在基底层的较低层，在提供较低谷物比例日粮的动物中发现密度更高。主要组织相容性复合体 2（MHCII）染色阳性的细胞最常见于血管周围位置和基底层下部与固有-粘膜下层之间的交界处。在摄入低谷物日粮的动物中，MHCII 阳性染色细胞的密度更高。谷物补充水平也与角质层（SCT）和颗粒层（SGT）的厚度、角质层的完整性和角化细胞的脱落有关。在这个评分系统中，使用 EMSB 染色并没有优于苏木精和伊红（H&E）的优势。我们得出结论，一个仅包括 SCT、SGT 和细胞间空间外观丧失程度的评分系统，可以根据谷物补充水平对动物群体进行区分。
