How absolute biomass intake can alter nutrient profile interpretation in free-ranging species: The case of protein intake in brown bears

If an animal eats a large amount of a diet of a low content of a macronutrient, it can still ingest a considerable amount of that macronutrient. Various animals have been shown to balance nutrient content with intake in this way. We use the brown bear (Ursus arctos) as a model species, given their recent classification as ‘low protein omnivores’, to show how taking biomass intake into account can affect macronutrient intake interpretation. We 1) calculated absolute protein intake from published results of self-selection diet studies with bears in captivity and 2) modelled absolute protein intake of Swedish brown bears in autumn while binging on a berry diet of low protein concentrations. In feeding experiments in captivity, the self-selected macronutrient composition of brown bear diets are characterized by protein percentages (both on a dry matter and metabolizable energy basis) that appear low when compared to diets of carnivores. However, when taking into account absolute food intake..., , # How absolute biomass intake can alter nutrient profile interpretation in free-ranging species: The case of protein intake in brown bears Dataset DOI: [10.5061/dryad.bnzs7h4nk](10.5061/dryad.bnzs7h4nk) ## Description of the data and file structure The datafile represents the calculations explained in the manuscript. All the original data is either from the cited sources, or are assumed based on assumptions explained in the manuscript. ### Files and variables #### File: ADC\_DataCalculationsAll\_250324.xlsx **Description:** The datafile contains four spreadsheets that explain the calculations made for the manuscript. The first spreadsheet is for all calculations relating to brown bears, the second spreadsheet for calculations relating to sloth bears, the third spreadsheet for calculations related to Giant pandas, and the fourth spreadsheet for calculations related to the remaining carnivores of the manuscript, including domestic dogs, wolves, domestic cats and feral cats. The cal...,若动物大量进食某宏量营养素（macronutrient）含量较低的日粮，仍可摄入相当数量的该宏量营养素。已有研究表明，多种动物均可通过此种方式实现营养素摄入与日粮营养含量的平衡。本研究以棕熊（Ursus arctos）作为模式物种——因其近期被归类为“低蛋白杂食动物”——用以阐释生物量摄入如何影响宏量营养素摄入的解读逻辑。我们通过两项工作展开研究：1）基于圈养熊的日粮自主选择研究的已发表结果，计算其绝对蛋白质摄入量；2）针对秋季以低蛋白浆果日粮为食的瑞典棕熊，构建其绝对蛋白质摄入模型。在圈养饲喂实验中，棕熊自主选择的日粮宏量营养素组成以蛋白质占比（基于干物质与可代谢能两种基准）为特征，相较于食肉动物日粮，其蛋白质占比看似较低。但当考虑绝对食物摄入量时…… # 绝对生物量摄入如何改变野生种群的营养特征解读：以棕熊的蛋白质摄入为例 数据集DOI：10.5061/dryad.bnzs7h4nk ## 数据与文件结构说明 本数据文件对应论文中阐述的各项计算过程。所有原始数据要么来自已引用的文献来源，要么基于论文中说明的假设进行估算。 ### 文件与变量 #### 文件：ADC_DataCalculationsAll_250324.xlsx **文件说明：** 本数据文件包含四个工作表，用于呈现论文中的各项计算过程。第一个工作表涵盖所有与棕熊相关的计算，第二个对应树懒熊的相关计算，第三个用于大熊猫的相关计算，第四个则用于论文中提及的其余食肉动物（包括家犬、灰狼、家猫与野猫）的相关计算。后续内容……