Zoological Research

343-348

Authors: Yi-Zhuo Sun,Si-Tong Liu,Xiao-Meng Li,Kang Zou

Research on in vitro culture and gene editing of domestic spermatogonial stem cells (SSCs) is of considerable interest but remains a challenging issue in animal science. In recent years, some progress on the isolation, purification, and genetic manipulation of porcine SSCs has been reported. Here, we summarize the characteristics of porcine SSCs as well current advances in their in vitro culture, potential usage, and genetic manipulation. Furthermore, we discuss the current application of gene editing in pig cloning technology. Collectively, this commentary aims to summarize the progress made and obstacles encountered in porcine SSC research to better serve animal husbandry, improve livestock fecundity, and enhance potential clinical use.

358-393

Authors: Nikolay A. Poyarkov Jr., Peter Geissler, Vladislav A. Gorin, Evgeniy A. Dunayev, Timo Hartmann, Chatmongkon Suwannapoom

We provide an integrative taxonomic analysis of the Lipinia vittigera species complex from mainland Southeast Asia. Based on examination of external morphology, color pattern, and 681 base pairs of the cytochrome oxidase subunit I (COI) mitochondrial gene, we demonstrate the presence of four morphologically distinct lineages of Lipinia in Vietnam, Cambodia, Thailand, and Malaysia, showing a sequence divergence ranging 15.5%–20.4%. All discovered lineages are discretely diagnosable from one another by a combination of scalation traits and color patterns. A review of the published distribution data and a re-examination of available type material revealed the following results: (1) distribution of L. vittigera (Boulenger, 1894) sensu stricto is restricted to Sundaland and the Thai-Malay Peninsula south of the Isthmus of Kra; (2) L. microcercus (Boettger, 1901) stat. nov. is elevated to full species rank; the species has a wide distribution from central and southern Vietnam across Cambodia to eastern Thailand; we regard Lygosoma vittigerum kronfanum Smith, 1922 and Leiolopisma pranensis Cochran, 1930 as its junior synonyms; (3) Lipinia trivittata sp. nov. occurs in hilly areas of southern Vietnam, Cambodia, and eastern Thailand; and (4) Lipinia vassilievi sp. nov. is currently known only from a narrow area along the Vietnamese-Cambodian border in the foothills of the central Annamite Mountain Range. We further provide an identification key for Lipinia occurring in mainland Southeast Asia.

404-415

Authors: Kai Chen, Yu-Hong Shi, Jiong Chen, Ming-Yun Li

Classical Fc receptors (FcRs) mediate the binding to and recognition of the Fc portion of antibodies and play an important role during immune responses in mammals. Although proteins similar to soluble FcRs have been identified in fish, little is known about the role of such proteins in fish immunity. Here, we cloned a cDNA sequence encoding a soluble Fc receptor for an immunoglobulin G (FcγR) homolog from ayu (Plecoglossus altivelis) (PaFcγRl). The predicted protein was composed of two immunoglobulin C2-like domains but lacked a transmembrane segment and a cytoplasmic tail. The PaFcγRl transcripts were distributed at low levels in all tested tissues, but significantly increased after Vibrio anguillarum infection. The PaFcγRl protein was expressed in the head kidney, trunk kidney, and neutrophils. Recombinant PaFcγRl (rPaFcγRl) was secreted when transfected into mammalian cells and the native protein was also detected in serum upon infection. rPaFcγRl was also demonstrated to bind to ayu IgM, as assessed by cell transfection. Suppressive activity of the recombinant mature protein of PaFcγRl (rPaFcγRlm) on in vitro anti-sheep red blood cell (SRBC) responses was detected by a modified hemolytic plaque forming cell assay. In conclusion, our study revealed that PaFcγRl is closely involved in the negative regulation of IgM production in the ayu spleen.

427-438

Authors: Dong-Dong Zhai, Wen-Jing Li, Huan-Zhang Liu, Wen-Xuan Cao, Xin Gao

Small populations with low genetic diversity are prone to extinction. Knowledge on the genetic diversity and structure of small populations and their genetic response to anthropogenic effects are of critical importance for conservation management. In this study, samples of Ancherythroculter nigrocauda, an endemic cyprinid fish from the upper reaches of Yangtze River, were collected from five sites to analyze their genetic diversity and population structure using mitochondrial cytochrome b gene and 14 microsatellite loci. Haplotype diversity, nucleotide diversity, and expected heterozygosity indicated that the A. nigrocauda populations had low genetic diversity, and decreased heavily from 2001 to 2016. Significant genetic differentiation was found among different populations in the cyt b gene and SSR markers based on the genetic differentiation index (F ST), whereas no differentiation was found in 2001. Haplotype genealogy showed that eight out of 15 haplotypes were private to one population. The SSR STRUCTURE analysis showed that there were four genetic clusters in the A. nigrocauda samples, with each population forming a single cluster, except for the Chishui River (CSR) and Mudong River (MDR) populations, which formed a common cluster. Therefore, loss of genetic diversity and increased genetic differentiation were found in the A. nigrocauda populations, which could be attributed to dam construction, overfishing, and water pollution in the upper Yangtze River. It is therefore recommended that the government should ban fishing, control water pollution, increase river connectivity, and establish artificial breeding and stocking.

449-455

Authors: Da-Peng Zhao, Bo-Song Li, Bao-Guo Li

Investigations on manual laterality in non-human primates can help clarify human evolutionary origins of hand preference and cerebral cognition. Although body posture can influence primate hand preference, investigations on how posture affects hylobatid manual laterality are still in their infancy. This study focused on how spontaneous bipedal behavioral tasks affect hand preference in Hylobatidae. Ten captive northern white-cheeked gibbons (Nomascus leucogenys) were chosen as focal subjects. Unimanual grooming during sitting posture and supported bipedal posture were applied as behavioral tasks. The gibbons displayed a modest tendency on left-hand preference during sitting posture and right-hand preference during supported bipedal posture, although no group-level hand preference was detected for either posture. From the sitting to supported bipedal posture, 70% of individuals displayed different degrees of right-side deviation trends. The strength of manual laterality in the supported bipedal posture was higher than that in the sitting posture. We found significant sex differences in manual laterality during supported bipedal posture but not during sitting posture. Thus, to a certain degree, bipedal posture in N. leucogenys facilitates stronger hand preference, elicits a rightward trend in manual laterality, and produces sex-specific hand preference.

466-470

Authors: Chang-Zhang Feng, Can-Chao Yang, Wei Liang

Nest sanitation is a ubiquitous behavior in birds and functions to remove foreign objects that accidentally have fallen into their nests. In avian brood parasitism, the host’s ability to recognize and reject parasitic eggs is a specific anti-parasitic behavior. Previous studies have shown that egg recognition may have evolved from nest sanitation behavior; however, few studies have offered evidence in support of this hypothesis. In the current study, we added one real white egg and one model egg to the nests of common tailorbirds (Orthotomus sutorius), the main host of plaintive cuckoos (Cacomantis merulinus), to explore the relationship between egg recognition ability in hosts and nest sanitation behavior. Results showed that common tailorbirds rejected both non-mimetic blue model eggs and mimetic white model eggs at a similar rate of 100%, but only rejected 16.1% of mimetic real white eggs. The egg rejection behavior of common tailorbirds towards both real and model eggs was consistent. However, when both blue model eggs and real white eggs were simultaneously added to their nests, the probability of rejecting the mimetic real white egg increased to 50%. The addition of blue model eggs not only increased the occurrence of nest sanitation behavior but also increased the ability to recognize and reject parasitic eggs. This suggests that nest sanitation may facilitate egg rejection in common tailorbird hosts.