Diet analysis is a critical content of animal ecology and the diet analysis methods have been constantly improving and updating. Contrary to traditional methods of high labor intensity and low resolution, the next generation sequencing (NGS) approach has been suggested as a promising tool for dietary studies, which greatly improves the efficiency and broadens the application range. Here we present a framework of adopting NGS and DNA metabarcoding into diet analysis, and discuss the application in aspects of prey taxa composition and structure, intra-specific and inter-specific trophic links, and the effects of animal feeding on environmental changes. Yet, the generation of NGS-based diet data and subsequent analyses and interpretations are still challenging with several factors, making it possible still not as widely used as might be expected. We suggest that NGS-based diet methods must be furthered, analytical pipelines should be developed. More application perspectives, including nutrient geometry, metagenomics and nutrigenomics, need to be incorporated to encourage more ecologists to infer novel insights on they work.

Hypoderma diana Brauer, 1858, poses a significant threat to species of deer, yet records of this species in China remain fragmented and lack comprehensive documentation. Following high mortality in wapiti populations in Inner Mongolia during 2023–2024, surveys were conducted in the Gaogesitai Hanwula Nature Reserve in March 2025. Species identity was established through rigorous morphological analysis of third-instar larvae and an emerged adult female using light and scanning electron microscopy, supplemented by a 689 bp COI fragment. Results confirmed H. diana as the causative agent, with larvae localized along the host’s vertebral column. Comparative SEM analysis of the antennomaxillary sensory complex in H. diana, H. bovis (Linnaeus, 1758), and H. lineatum (Villers, 1789) revealed undifferentiated, volcano-like warts, contrasting sharply with the highly differentiated antennae and sensilla of Oestrus ovis Linnaeus, 1758. This study represents an inaugural record of H. diana in the Chifeng region and provides the first atlas of diagnostic features for both third-instar larvae and adults. These findings document H. diana as a critical agent of myiasis in the Manchurian wapiti, refining its known epidemiological profile in China and establishing an essential morphological reference for future wildlife health surveillance.

Given the ongoing global decline in biodiversity, species reintroduction has become an important strategy for the conservation of endangered wildlife. Père David’s deer (Elaphurus davidianus), a historically extinct-in-the-wild species successfully reintroduced in China, represents a useful model for evaluating ecological responses following reintroduction into different habitats. Increasing evidence suggests that fecal microbiota can serve as a non-invasive indicator of host-associated microbial communities and their variation under different conditions. In this study, we investigated the fecal microbiota of a reintroduced population in the Daqingshan National Nature Reserve (Inner Mongolia). A total of 90 fresh fecal samples were collected between December 2021 and October 2023 across different seasonal periods. High-throughput 16S rRNA gene sequencing was used to characterize microbial community structure, and comparative analyses were conducted alongside published datasets from populations in Beijing and Shishou. The results revealed significant seasonal variation in microbial community composition and diversity, with distinct clustering of rainy, dry, and transitional (October) samples. Several taxa exhibited differential enrichment between seasons, suggesting temporal shifts in microbial community structure. A comparative analysis with other populations (Beijing and Shishou) revealed differences in microbial composition at broad taxonomic levels, suggesting potential variations related to regional environmental conditions, diet, and management practices. Overall, the observed patterns are consistent with seasonal variation in plant resource availability and highlight the potential influence of geographic context on microbial community structure. This study provides baseline data on the fecal microbiota of Père David’s deer in a semi-arid steppe environment and the potential indication of host suitability from the perspective of the microbiome.