Winter supplemental feeding (SF) is commonly used to improve the survival of captive wildlife. To investigate the impact of winter supplementation on the gut microbiota of wildlife, we assessed changes in the gut microbiota of red deer (Cervus elaphus) during the supplementary and non-supplementary feeding (NSF) groups using 16S rRNA sequencing technology. We found no significant differences in the diversity of the gut microbiota between SF and NSF except for the Simpson’s index. However, the relative abundance of Bacteroidetes, Lentisphaerae, and Proteobacteria in the gut microbiota was significantly higher during SF. Further, genera such as Intestinimonas, Rikenella, Lawsonibacter, Muribaculum, and Papillibacter were more abundant during SF. Beta diversity analysis showed significant differences between SF and NSF. The microbes detected during SF were primarily associated with lipid metabolism, whereas those detected during NSF were linked to fiber catabolism. High-energy feed affects the gut microbial composition and function in red deer. During SF, the gut microbes in red deer were enriched in microorganisms associated with butyrate and lipid metabolism, such as R. microfusus, M. intestinale, and Papillibacter cinnamivorans. These gut microbes may be involved in ameliorating obesity associated with high-energy diets. In summary, SF is a reasonable and effective management strategy.
Seasonal dietary shifts in animals are important strategies for ecological adaptation. An increasing number of studies have shown that seasonal dietary shifts can influence or even determine the composition of gut microbiota. The Turpan wonder gecko, Teratoscincus roborowskii, lives in extreme desert environments and has a flexible dietary shift to fruit‐eating in warm seasons. However, the effect of such shifts on the gut microbiota is poorly understood. In this study, 16S rRNA sequencing and LC–MS metabolomics were used to examine changes in the gut microbiota composition and metabolic patterns of T. roborowskii. The results demonstrated that the gut microbes of T. roborowskii underwent significant seasonal changes, and the abundance of phylum level in autumn was significantly higher than spring, but meanwhile, the diversity was lower. At the family level, the abundance and diversity of the gut microbiota were both higher in autumn. Firmicutes, Bacteroidetes, and Proteobacteria were the dominant gut microbes of T. roborowskii. Verrucomicrobia and Proteobacteria exhibited dynamic ebb and flow patterns between spring and autumn. Metabolomic profiling also revealed differences mainly related to the formation of secondary bile acids. The pantothenate and CoA biosynthesis, and lysine degradation pathways identified by KEGG enrichment symbolize the exuberant metabolic capacity of T. roborowskii. Furthermore, strong correlations were detected between metabolite types and bacteria, and this correlation may be an important adaptation of T. roborowskii to cope with dietary shifts and improve energy acquisition. Our study provides a theoretical basis for exploring the adaptive evolution of the special frugivorous behavior of T. roborowskii, which is an important progress in the study of gut microbes in desert lizards.
Seasonal dietary shifts of animals are important ecological adaptation strategies. An increasing number of studies have shown that seasonal dietary shifts can influence or even determine the composition of gut microbiota. The turpan wonder gecko Teratoscincus roborowskii lives in extreme desert environments, which have flexible dietary shift to fruit-eating in warm seasons. But the impact of such shifts on gut microbiota is poorly understood. Here, 16SrRNA sequencing and LC-MS metabolomics we used to examine the changes of gut microbiota composition and metabolic pattern of T. roborowskii. The results demonstrated that the gut microbes of T. roborowskii had significant seasonal changes, the diversity and abundance of gut microbiota in autumn were higher than those of in spring. Firmicutes, Bacteroidetes and Proteobacteria were the core gut microbes of T. roborowskii. Verrucomicrobia and Proteobacteria exhibit dynamic pattern of ebb and flow between spring and autumn.The composition and structure of gut microbes in different seasons perform specific metabolic functions, and this change may be an important adaptation for T. roborowskii to cope with dietary shifts and improve energy acquisition. Our study will provide a theoretical basis for exploring the adaptive evolution to special frugivorous behavior of the T. roborowskii, which is an important supplement to the study of the gut microbiology of desert lizards.
Accurate age determination is fundamental for investigating fish population dynamics and growth patterns. This study used the lapillus to determine age in Triplophysa strauchii populations from an oxbow lake and a stream. Growth patterns were evaluated using three models (the Von Bertalanffy, Gompertz, and Logistic models). The oxbow lake population showed faster growth and longer lifespan (6 years in Dacao Lake; 5 years in Liutiao Stream). Conversely, the stream population displayed a trend toward smaller size and younger age. Both populations exhibited higher Fulton’s condition factor in juveniles than in adults. The species exhibited a fast-growth type, with similar fitting results across models. These findings reflect subtle differentiation in life history strategies across habitats, likely related to environmental conditions and competitive pressure from invasive species. These insights into T. strauchii life history underscore the importance of further research to support conservation and sustainable management of this endemic species.
This study investigated retinal interspecific differences between two sympatric lizards from the Turpan Basin of Xinjiang that occupy distinct microhabitats. Eremias roborowskii inhabits shrublands, while Phrynocephalus axillaris lives in open sandy areas. We adopted retinal whole-mounting, paraffin sectioning, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to compare retinal structure, oil droplet traits, photoreceptor arrangement, and ultrastructural characteristics between the two species. Both species exhibited five types of colored oil droplets, a temporal fovea, and a highly vascularized conus papillaris, confirming cone-dominant retinas. P. axillaris had larger oil droplets with an average diameter of 3.719 ± 1.100 μm. In contrast, E. roborowskii showed a higher oil droplet density of 1473 ± 1203 ind/mm2. The inner plexiform layer (IPL) was significantly thicker in E. roborowskii (56.01 ± 14.76 μm) relative to P. axillaris (50.76 ± 15.25 μm). The two species also differed markedly in photoreceptor ultrastructure. E. roborowskii contained mitochondria-rich ellipsoids, while P. axillaris possessed glycogen-enriched paraboloids. These structural variations reflect compatibility with local ambient light conditions. E. roborowskii is predisposed to suit diffuse shrubland light through high droplet density and mitochondrial-dominant ellipsoids, whereas P. axillaris tends to accommodate intense open-field sunlight via larger oil droplets and well-developed paraboloids. This study provides key morphological evidence to reveal how microhabitat divergence drives retinal specialization among desert reptiles.
Sexual dimorphism is widespread among fish species, yet the ecological factors shaping this phenomenon remain poorly understood. Using traditional morphometric analyses of 319 specimens together with geometric morphometrics, this study examined sexual dimorphism in Triplophysa strauchii across two basins. The results showed that both the 42 specimens from the oxbow lake habitat in DL and the 34 specimens from the sedimentary‐bottom stream in LS exhibited male‐biased sexual size dimorphism (SSD). Males had larger body size, larger heads, and greater caudal peduncle depth, traits that may enhance locomotor and foraging performance. These findings suggest that sexual selection is an important mechanism underlying sexual dimorphism in T. strauchii across different river basins. The operculum also exhibited sexual differences across basins: females had narrower opercula, whereas males had more rounded and obtuse opercula. Canonical variate analysis (CVA) based on Procrustes distances further indicated that sexual dimorphism in opercular shape was more pronounced in DL than in LS. Differences in eye size were also observed: females from Dacao Lake had larger eyes than males, whereas males from Liutiao Stream had larger eyes than females. Together, these results reveal fine‐scale variation in fish sexual dimorphism in response to diverse selective forces (these inferences are based on habitat differences and previous studies, not direct field measurements).