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The quality and completeness of the reference database have a direct impact on the accuracy of forage plant identification, thereby influencing the level of conservation and management of wildlife resources. In our research, target amplification was subjected to first-generation sequencing to assemble a local reference database using chloroplast trnL metabarcoding. We found that the primers c-h outperformed g-h as a universal DNA metabarcoding and 162 valid choloroplast trnL sequences were submitted (GenBank ID: PP081756 - PP081917), which exhibited an obvious preference for A and T nucleotides (60.49%). The haplotype diversity (Hd), nucleotide diversity (Pi) and average number of nucleotide differences (K) of these trnL sequences were 0.978, 0.0484 and 4.743, respectively. To assess the availability of the local database in identifying the diet of South China sika deer (Cervus nippon kopschi), high-throughput metabarcoding sequencing and BLAST analysis were performed. Ultimately, 25 forage plant species were identified, belonging to 19 families and 25 genera. Shrubs and herbaceous plants, such as Potentilla freyniana, Persicaria perfoliata, Rosa laevigata and Ardisia japonica etc, dominated the forage plants. This study established a local trnL reference database that holds immense value for the forage plant identification and nutritional evaluation for sika deer and other sympatric herbivores, as well as the conservation and management of biodiversity. [ABSTRACT FROM AUTHOR]

Background: Food provides essential nutrients and energy necessary for animals to sustain life activities. Accordingly, dietary niche analysis facilitates the exploration of foraging strategies and interspecific relationships among wildlife. The vegetation succession has reduced understory forage resources ( i.e ., shrubs and herbs) available to sika deer ( Cervus nippon kopschi ). Little is known about the summer foraging strategies or the interspecific relationship between sika deer and Reeves' muntjac ( Muntiacus reevesi )., Methods: The present study used high-throughput sequencing and DNA metabarcoding techniques to investigate the feeding habits and interspecific relationships between sika deer and Reeves' muntjac in our study., Results: A total of 458 amplicon sequence variants (ASVs) were identified from fecal samples, with 88 ASVs (~19.21%) unique to sika deer and 52 ASVs (~11.35%) unique to Reeves' muntjac, suggesting the consumption and utilization of specific food items for the two species. The family Rosaceae was the most abundant for both species, especially Rubus spp. and Smilax china . Alpha diversity (local species richness) indicated that the dietary species richness of sika deer was higher than that of Reeves' muntjac, but the difference was not statistically significant. Sika deer also exhibited a higher evenness index ( J' = 0.514) than Reeves' muntjac ( J' = 0.442). Linear discriminant effect size analysis revealed significant differences in forage plants between the two herbivores. The niche breadths of sika deer and Reeves' muntjac were 11.36 and 14.06, respectively, and the dietary niche overlap index was 0.44. Our findings indicate the diet partitioning primarily manifested in the differentiation of food items and the proportion, which ultimately reduces the overlap of nutritional niches and helps avoid conflicts resulting from resource utilization. This study provides a deeper insight into the diversity of foraging strategies and the interspecific relationship of herbivores from the food dimension., Competing Interests: The authors declare that they have no competing interests., (© 2024 Li et al.)

The quality and completeness of the reference database have a direct impact on the accuracy of forage plant identification, thereby influencing the level of conservation and management of wildlife resources. In our research, target amplification was subjected to first-generation sequencing to assemble a local reference database using chloroplast trnL metabarcoding. We found that the primers c-h outperformed g-h as a universal DNA metabarcoding and 162 valid choloroplast trnL sequences were submitted (GenBank ID: PP081756 - PP081917), which exhibited an obvious preference for A and T nucleotides (60.49%). The haplotype diversity ( Hd ), nucleotide diversity ( Pi ) and average number of nucleotide differences ( K ) of these trnL sequences were 0.978, 0.0484 and 4.743, respectively. To assess the availability of the local database in identifying the diet of South China sika deer ( Cervusnipponkopschi ), high-throughput metabarcoding sequencing and BLAST analysis were performed. Ultimately, 25 forage plant species were identified, belonging to 19 families and 25 genera. Shrubs and herbaceous plants, such as Potentillafreyniana , Persicariaperfoliata , Rosalaevigata and Ardisiajaponica etc, dominated the forage plants. This study established a local trnL reference database that holds immense value for the forage plant identification and nutritional evaluation for sika deer and other sympatric herbivores, as well as the conservation and management of biodiversity., Competing Interests: No conflict of interest to declare Disclaimer: This article is (co-)authored by any of the Editors-in-Chief, Managing Editors or their deputies in this journal., (Yuqin Liu, Dandan Wang, Zhiming Cao, Wuhua Liu, Zechun Bao, Weiwei Zhang, Yongtao Xu.)

Species co-existence depends on how organisms utilize their environment and resources. Little is known about the winter diet composition and sympatric co-existence of South China sika deer and its companion species in Taohongling. In this study, high-throughput sequencing and metabarcoding trnL were used to study the diet composition and interspecific relationship including sika deer, Reeve's muntjac, and Chinese hare. Our results show that 203 genera in 90 families are contained in the diet of sika deer, 203 genera in 95 families for Reeve's muntjac, and 163 genera in 75 families for Chinese hare. Sika deer fed on Rubuschingii , Loropetalumchinense , and Euryajaponica in winter, accounting for 75.30%; Reeve's muntjac consumed mainly R.chingii , E.japonica , and Euonymusgrandiflorus , accounting for 68.80%, and Chinese hare mainly fed on R.chingii , Smilaxchina , and Rhuschinensis , accounting for 41.98%. The Shannon index showed no significant difference between groups ( p > 0.05). The NMDS analysis found considerable overlap among three species. Sika deer and Reeve's muntjac consumed similar forage plants but varied greatly in Chinese hare, which occupied the widest choice in winter, resulting in higher diet breadth and increased dietary divergence, thereby reducing competition and facilitating coexistence. The diet niche overlap index among them, as represented by Pianka's index, ranging from 0.62 between sika deer and Chinese hare to 0.83 between sika deer and Reeve's muntjac, which indicated a more similar niche and potential competition in closely related species. Our findings provide a new diet perspective of three herbivores, leading to a more comprehensive understanding of resource partitioning and species coexistence., (Dandan Wang, Xiaolong Hu, Minling Li, Jie Liu, Ming Tang, Wuhua Liu, Jianwen Zhan, Yongtao Xu, Weiwei Zhang.)

Background: The size and versatility of anterolateral thigh (ALT) flap enables a bi-paddle flap to cover complex and extensive defects optimally. However, it is characterized by variations in the sources of blood vessels and in the number of perforators, which increases the chances of failure of harvesting a bi-paddle flap. We present our method to overcome such failure. This is the first study exploring the optimal salvaging algorithm to overcome harvesting failure with the bi-paddle ALT flap., Methods: From January 2014 to December 2020, in 9 patients to be treated with bi-paddle ALT flap for soft-tissue defects (range, 48-288 cm 2 ), there was failure of flap harvest because of perforator variations. We redesigned and converted the flaps to other forms for harvest intraoperatively, based on the characteristics of the defect, and the number and sources of perforators., Results: Salvage of flap harvest was successfully performed in all 9 cases. In 4 cases the flap with a single perforator was converted to widened-single-perforator flaps; in 2 cases, a single perforator was converted to a de-epithelialized flap; in 2 cases of 2 perforators from different main branches, conversion was to sequential chimeric flaps; in the remaining case of 2 perforators from the descending branch and transverse branch, conversion was to a combined transverse-and-descending branches flap. Venous compromise occurred in only 1 case, and the patient survived after revised surgery. Local infection in the receiving area occurred in 3 cases, and was cured by wound dressing. All flaps survived (follow-up 5-24 months)., Conclusions: Despite preoperative preparation, anatomic variations resulted in failure of bi-paddle ALT flap harvesting. As shown by our results, it is feasible to redesign and convert the bi-paddle flap to other forms based on the defect characteristics, and the number and sources of perforators., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://atm.amegroups.com/article/view/10.21037/atm-22-1118/coif). The authors have no conflicts of interest to declare., (2022 Annals of Translational Medicine. All rights reserved.)

Objective: To investigate the effectiveness of perforator propeller flap of lower limb in the treatment of foot and ankle defect in children., Methods: The clinical data of 28 children with foot and ankle defect treated with perforator propeller flap of lower limb between January 2018 and January 2021 were retrospectively analyzed. There were 18 boys and 10 girls with an average age of 7.3 years (range, 6-14 years). There were 8 cases of traffic accident injury and 20 cases of chronic infection wound. The disease duration was 2-4 months, with an average of 2.8 months. After thorough debridement, the residual wound size ranged from 5 cm×4 cm to 9 cm×5 cm. Repairing was performed after 7-28 days of the infection in control. According to the location, size, and shape of the wound, the perforating vessels were located by ultrasonic Doppler, and the perforator propeller flap (area ranged from 6 cm×5 cm to 11 cm×6 cm) was designed and harvested to repair the wound. Flap transfer combined with free split-thickness skin graft covered the wound in 2 cases. The donor site was sutured directly (22 cases) or repaired with skin graft (6 cases)., Results: Twenty-six flaps survived, of which 20 cases were in primary healing, and 6 cases had epidermal necrosis at the end of small paddle, which healed after dressing change. Necrosis occurred in 2 cases due to venous crisis which healed after anterolateral femoral flap free transplantation. Primary wound healing was achieved in donor site. All 28 children were followed up 6-24 months (mean, 10.5 months). The texture, shape, and motor function of the lower limb was satisfactory. At last follow-up, the American Orthopaedic Foot and Ankle Association (AOFAS) score was 89.8±8.0, which was significantly different from the preoperative score (79.6±10.4) ( t =-11.205, P <0.001); 20 cases were excellent, 6 cases were good, and 2 cases were poor, and the excellent and good rate was 92.8%., Conclusion: The perforator propeller flap of lower limb in children has its own characteristics. It is a reliable method to repair the foot and ankle defect in children.