Breeding Biology of Isolated Captive Dalmatian Pelicans (Pelecanus crispus) at the Shanghai Zoo, China

The breeding biology of a captive, isolated population of Dalmatian Pelicans (Pelecanus crispus) at theShanghaiZoo,China, was studied from 2007 to 2019. The breeding age of the Dalmatian Pelicans was estimated at three to four years old, and they started breeding in late October or early November. The clutch size varied between one and two eggs per nest, and the eggs were 83.2 ±4.8 mmin length, 55.6 ±2.9 mmin breadth and 136.1 ±21.5 gin weight. The fertility fluctuated slightly, with an average rate of 38.7% ± 9.7%, but remained consistently low. The survival rate of chicks fluctuated substantially from 0% to 100%, with an average survival rate of 68.6% ± 27.6%. The averaged values of observed heterozygosity, expected heterozygosity and polymorphism information content were 0.468, 0.465 and 0.446, respectively. It indicated that the population had a low heterozygosity and genetic diversity. There was a significant change in the breeding index compared to that recorded 40 years ago, which indicates that inbreeding depression has occurred in this small, isolated, captive population of Dalmatian Pelicans. These results can be used to improve management of Dalmatian Pelicans in captivity.

Isolation and characterisation of human gingival margin-derived STRO-1/MACS^+ and MACS^-cell populations

Recently,gingival margin-derived stem/progenitor cells isolated via STRO-1/magnetic activated cell sorting（MACS） showed remarkable periodontal regenerative potential in vivo.As a second-stage investigation,the present study＇s aim was to perform in vitro characterisation and comparison of the stem/progenitor cell characteristics of sorted STRO-1-positive（MACS~＋） and STRO-1-negative（MACS^-） cell populations from the human free gingival margin.Cells were isolated from the free gingiva using a minimally invasive technique and were magnetically sorted using anti-STRO-1 antibodies.Subsequently,the MACS~＋ and MACS^- cell fractions were characterized by flow cytometry for expression of CD14,CD34,CD45,CD73,CD90,CD105,CD146/MUC18 and STRO-1.Colony-forming unit（CFU） and multilineage differentiation potential were assayed for both cell fractions.Mineralisation marker expression was examined using real-time polymerase chain reaction（PCR）.MACS~＋ and MACS- cell fractions showed plastic adherence.MACS~＋ cells,in contrast to MACS- cells,showed all of the predefined mesenchymal stem/progenitor cell characteristics and a significantly higher number of CFUs（P〈0.01）.More than 95%of MACS~＋ cells expressed CD105,CD90 and CD73;lacked the haematopoietic markers CD45,CD34 and CD14,and expressed STRO-1 and CD146/MUC18.MACS- cells showed a different surface marker expression profile,with almost no expression of CD14 or STRO-1,and more than 95%of these cells expressed CD73,CD90 and CD146/MUC18,as well as the haematopoietic markers CD34 and CD45 and CD105.MACS~＋ cells could be differentiated along osteoblastic,adipocytic and chondroblastic lineages.In contrast,MACS- cells demonstrated slight osteogenic potential.Unstimulated MACS~＋ cells showed significantly higher expression of collagen I（P〈0.05） and collagen III（P〈0.01）,whereas MACS^- cells demonstrated higher expression of osteonectin（P〈0.05;MannWhitney）.The present study is the first to compare gingival MACS~＋ and MACS- cell populations demonstrating that MACS~＋ cells,in contrast to MACS- cells,harbour stem/progenitor cell characteristics.This study also validates the effectiveness of the STRO-l/MACS~＋technique for the isolation of gingival stem/progenitor cells.Human free gingival margin-derived STRO-1/MACS~＋ cells are a unique renewable source of multipotent stem/progenitor cells.

Habitat, occurrence and conservation status of the Saharo-Macaronesian and Southern-Mediterranean element Fagonia cretica L. (Zygophyllaceae) in Italy

Fagonia cretica L. is an important component of Mediterranean dry grasslands and a rare and isolated species of Italian flora. In this study, an assessment is presented on the distribution, habitat, and conservation status of F. cretica in Italy. The results of field investigation and herbarium analysis show that this species grows in a small area within the southern Calabria region characterized by a warmest and driest Mediterranean climate on the Italian peninsula. F. cretica is a semi-desert plant species growing in Italy in only one peripheral and isolated population at the northern limit of its distribution. Plant community analysis, using the phytosociological method, shows that F. cretica grows in wintergreen perennial dry grasslands dominated by Lygeum {partum and Hyparrhenia hirta. F. crelica plant communities are located in thermo-xeric habits such as south-, southeast- and east-facing slopes on clays and sandy clays in southern Calabria. The population of F. cretica is fragmented in six neighbouring localities, with two of which belonging to a Site of Community Importance （SC1）. The conservation status of F. cretica population is not very good, and is defined as ＂Critically Endangered＂ in accordance with IUCN criteria. There are many threats affecting the F. crelica population in ltaly, primarily the changes in land uses due to urban expansion and reforestation with exotic plants. The southern end of the Italian peninsula hosts other plants from thermo-xeric habits that do not adapt to the current local climate. This territory can be considered as a microrefugia for plants currently distributed in the arid territory of the southern Mediterranean. These results contribute to the discussion of some conservation measures, and the possibility of establishing a micro-reserve. For all these reasons, we propose to include F. cretica in the lists of protected plant species at regional （Calabria） and country （Italy） scales in Italy.

Genomic divergence and mutation load in the Begonia masoniana complex from limestone karsts

Understanding genome-wide diversity,inbreeding,and the burden of accumulated deleterious mutations in small and isolated populations is essential for predicting and enhancing population persistence and resilience.However,these effects are rarely studied in limestone karst plants.Here,we re-sequenced the nuclear genomes of 62 individuals of the Begonia masoniana complex(B.liuyanii,B.longgangensis,B.masoniana and B.variegata)and investigated genomic divergence and genetic load for these four species.Our analyses revealed four distinct clusters corresponding to each species within the complex.Notably,there was only limited admixture between B.liuyanii and B.longgangensis occurring in overlapping geographic regions.All species experienced historical bottlenecks during the Pleistocene,which were likely caused by glacial climate fluctuations.We detected an asymmetric historical gene flow between group pairs within this timeframe,highlighting a distinctive pattern of interspecific divergence attributable to karst geographic isolation.We found that isolated populations of B.masoniana have limited gene flow,the smallest recent population size,the highest inbreeding coefficients,and the greatest accumulation of recessive deleterious mutations.These findings underscore the urgency to prioritize conservation efforts for these isolated population.This study is among the first to disentangle the genetic differentiation and specific demographic history of karst Begonia plants at the whole-genome level,shedding light on the potential risks associated with the accumulation of deleterious mutations over generations of inbreeding.Moreover,our findings may facilitate conservation planning by providing critical baseline genetic data and a better understanding of the historical events that have shaped current population structure of rare and endangered karst plants.