This study was conducted to ascertain the negative effects of dietary low-density polyethylene microplastics (LDPE-MPs) exposure on growth, nutrient digestibility, body composition and gut histology of Nile tilapia (Oreochromis niloticus). Six sunflower meal-based diets (protein 30.95%; fat 8.04%) were prepared; one was the control (0%) and five were incorporated with LDPE-MPs at levels of 2, 4, 6, 8 and 10% in sunflower meal-based diets. A total of eighteen experimental tanks, each with 15 fingerlings, were used in triplicates. Fish were fed at the rate of 5% biomass twice a day for 60 days. Results revealed that best values of growth, nutrient digestibility, body composition and gut histology were observed by control diet, while 10% exposure to LDPE-MPs significantly (P < 0.05) reduced weight gain (WG%, 85.04%), specific growth rate (SGR%, 0.68%), and increased FCR (3.92%). The findings showed that higher level of LDPE-MPs (10%) exposure in the diet of O. niloticus negatively affects nutrient digestibility. Furthermore, the results revealed that the higher concentration of LDPE-MPs (10%) had a detrimental impact on crude protein (11.92%) and crude fat (8.04%). A high number of histological lesions were seen in gut of fingerlings exposed to LDPE-MPs. Hence, LDPE-MPs potentially harm the aquatic health.

Graphical Abstract

中文翻译：

---

膳食暴露聚乙烯微塑料对尼罗罗非鱼 (Oreochromis niloticus) 鱼种生长、营养物质消化率、屠体和肠道组织学的毒理学评估

本研究旨在确定膳食低密度聚乙烯微塑料 (LDPE-MP) 暴露对尼罗罗非鱼 ( Oreochromis niloticus ) 生长、营养消化率、身体成分和肠道组织学的负面影响。准备了六种以葵花籽粕为主的日粮（蛋白质30.95%；脂肪8.04%）；一种是对照 (0%)，五种是在以葵花粉为基础的日粮中添加了 2%、4%、6%、8% 和 10% 的 LDPE-MP。总共使用了 18 个实验池，每个池有 15 条鱼种，一式三份。以5%生物量的比例每天喂鱼两次，持续60天。结果显示，通过对照饮食观察到生长、营养消化率、身体成分和肠道组织学的最佳值，而 10% 的 LDPE-MP 暴露显着 ( P  < 0.05) 降低了体重增加 (WG%, 85.04%)、特定生长率（SGR%，0.68%），并且 FCR 增加（3.92%）。研究结果表明，尼罗罗非鱼饮食中较高水平的 LDPE-MP（10%）暴露会对营养物质的消化率产生负面影响。此外，结果表明，较高浓度的 LDPE-MP（10%）对粗蛋白（11.92%）和粗脂肪（8.04%）产生不利影响。在暴露于 LDPE-MP 的鱼种肠道中发现大量组织学损伤。因此，LDPE-MP 可能危害水生健康。

图形概要