Zoological Research

174-181

Authors: Xun-Xun CHU, Joshua Dominic Rizak, Shang-Chuan YANG, Jian-Hong WANG, Yuan-Ye MA, Xin-Tian HU

Postpartum depression (PPD) is a modified form of major depressive disorders (MDD) that can exert profound negative effects on both mothers and infants than MDD. Within the postpartum period, both mothers and infants are susceptible; but because PPD typically occurs for short durations and has moderate symptoms, there exists challenges in exploring and addressing the underlying cause of the depression. This fact highlights the need for relevant animal models. In the present study, postpartum adult female cynomolgus monkeys (Macaca fascicularis) living in breeding groups were observed for typical depressive behavior. The huddle posture behavior was utilized as an indicator of behavioral depression postpartum (BDP) as it has been established as the core depressive-like behavior in primates. Monkeys were divided into two groups: A BDP group (n=6), which were found to spend more time huddling over the first two weeks postpartum than other individuals that formed a non-depression control group (n=4). The two groups were then further analyzed for locomotive activity, stressful events, hair cortisol levels and for maternal interactive behaviors. No differences were found between the BDP and control groups in locomotive activity, in the frequencies of stressful events experienced and in hair cortisol levels. These findings suggested that the postpartum depression witnessed in the monkeys was not related to external factors other than puerperium period. Interestingly, the BDP monkeys displayed an abnormal maternal relationship consisting of increased infant grooming. Taken together, these findings suggest that the adult female cynomolgus monkeys provide a natural model of behavioral postpartum depression that holds a number of advantages over commonly used rodent systems in PPD modeling. The cynomolgus monkeys have a highly-organized social hierarchy and reproductive characteristics without seasonal restriction—similar to humans—as well as much greater homology to humans than rodents. As such, this model may provide a greater translational efficiency and research platform for systematically investigating the etiology, treatment, prevention of PPD.

186-195

Authors: Ai-Hua LEI, Gao-Hong ZHANG, Ren-Rong TIAN, Jia-Wu ZHU, Hong-Yi ZHENG, Wei PANG, Yong-Tang ZHENG

The northern pig-tailed macaque (Macaca leonina) has been identified as an independent species of Old World monkey, and we previously found that PBMCs from M. leonina were susceptible to human immunodeficiency virus type 1 (HIV-1), which may be due to the absence of a TRIM5 protein restricting HIV-1 replication. Here we investigated the infection potentials of six laboratory adapted HIV-1 strains and three primary HIV-1 isolates in PBMCs from M. leonina. The results indicate that these strains are characterized by various but low replication levels, and among which, HIV-1_NL4-3 shows the highest replication ability. Based on the abundant evidence of species-specific interactions between restriction factors APOBEC3 and HIV/SIV-derived Vif protein, we subsequently examined the replication potentials of vif-substituted HIV-1 (HSIV) in M. leonina PBMCs. Notably, HSIV-vif_mac and stHIV-1_SV chimeras, two HIV-1_NL4-3-derived viruses encoding the viral infectivity factor (Vif) protein from SIV_mac239, replicated robustly in cells from M. leonina, which suggests that HSIV could effectively antagonize the antiviral activity of APOBEC3 proteins expressed in cells of M. leonina. Therefore, our data demonstrate that M. leonina has the potential to be developed into a promising animal model for human AIDS.

204-213

Authors: Liang-Wei CUI, Qing-Lei SUN, Bao-Guo LI

Different types of dominance hierarchies reflect different social relationships in primates. In this study, we clarified the hierarchy and social relationships in a one-male unit of captive Rhinopithecus bieti observed between August 1998 and March 1999. Mean frequency of agonistic behaviour among adult females was 0.13 interactions per hour. Adult females exhibited a linear hierarchy with a reversal of 10.9%, indicating an unstable relationship; therefore, R. bieti appears to be a relaxed/tolerant species. The lack of a relationship between the agonistic ratio of the adult male towards adult females and their ranks indicated that males did not show increased aggression towards low-ranking females. Differentiated female affiliative relationships were loosely formed in terms of the male, and to some extent influenced by female estrus, implying that relationships between the male and females is influenced by estrus and not rank alone. A positive correlation between the agonistic ratio of adult females and their ranks showed that the degree to which one female negatively impacted others decreased with reduction in rank. Similarly, a positive correlation between the agonistic ratio of females and differences in rank suggests that a female had fewer negative effects on closely ranked individuals than distantly ranked ones. These data indicate that rank may influence relationships between females. A steeper slope of regression between the agonistic ratio and inter-female rank differences indicated that the extent of the power difference in high-ranking females exerting negative effects on low-ranking ones was larger during the mating season than the birth season, suggesting that rank may influence the mating success of females.

222-230

Authors: Briana BAUER, Lori K. SHEERAN, Megan D. MATHESON, Jin-Hua LI, R. Steven WAGNER

Adult male Tibetan (Macaca thibetana), Barbary (M. sylvanus), and stump-tailed macaques (M. arctoides) engage in bridging, a ritualized infant-handling behavior. Previous researchers found a bias toward the use of male infants for this behavior, but its function is debated. Explanations include three hypotheses: paternal care, mating effort, and agonistic buffering. We studied a group of habituated, provisioned Tibetan macaques to test whether adult males' affiliative relationships with females predicted their use of an infant for bridging. We also examined biases for sex, age, and individual in males' choice of bridging infant. We collected data via all occurrences, focal animal, and scan methods, from August to September 2011 at the Valley of the Wild Monkeys, China. We found that male infants were significantly preferred over females for bridging, but of three male infants in the group, only one was used by all males, while one male infant was used less often than expected. Adult males had females they were significantly more likely to be proximate to and/or to groom, but these corresponded to the mother of the bridging infant for only one male. Our results are most consistent with the agonistic buffering hypothesis: lower-ranked males used the alpha male's preferred bridging infant in an attempt to regulate their interactions with the alpha.

240-248

Authors: Yu FAN, Dan-Dan YU, Yong-Gang YAO

While the recent release of the Chinese tree shrew (Tupaia belangeri chinensis) genome has made the tree shrew an increasingly viable experimental animal model for biomedical research, further study of the genome may facilitate new insights into the applicability of this model. For example, though the tree shrew has a rapid rate of speed and strong jumping ability, there are limited studies on its locomotion ability. In this study we used the available Chinese tree shrew genome information and compared the evolutionary pattern of 407 locomotion system related orthologs among five mammals (human, rhesus monkey, mouse, rat and dog) and the Chinese tree shrew. Our analyses identified 29 genes with significantly high ω (Ka/Ks ratio) values and 48 amino acid sites in 14 genes showed significant evidence of positive selection in the Chinese tree shrew. Some of these positively selected genes, e.g. HOXA6 (homeobox A6) and AVP (arginine vasopressin), play important roles in muscle contraction or skeletal morphogenesis. These results provide important clues in understanding the genetic bases of locomotor adaptation in the Chinese tree shrew.

92-98

Authors: Xin-Liang SHAO, Shao-Yu HE, Xin-Ying ZHUANG, Ying FAN, Ya-Hui LI, Yong-Gang YAO

In honeybee (Apis mellifera) colonies, queens and workers are alternative forms of the adult female honeybee that develop from genetically identical zygotes but that depend on differential nourishment. Queens and workers display distinct morphologies, anatomies and behavior, better known as caste differentiation. Despite some basic insights, the exact mechanism responsible for this phenomenon, especially at the molecular level, remains unclear although some progress has been achieved. In this study, we examined mRNA levels of the TOR (target of rapamycin) and Dnmt3 (DNA methyltransferase 3) genes, closely related to caste differentiation in honeybees. We also investigated mRNA expression of the S6K (similar to RPS6-p70-protein kinase) gene linked closely to organismal growth and development in queen and worker larvae (1-day and 3-day old). Last, we investigated the methylation status of these three genes in corresponding castes. We found no difference in mRNA expression for the three genes between 1st instar queen and worker larvae; however, 3rd instar queen larvae had a higher level of TOR mRNA than worker larvae. Methylation levels of all three genes were lower in queen larvae than worker larvae but the differences were not statistically significant. These findings provide basic data for broadening our understanding of caste differentiation in female honeybees.

108-117

Authors: Shou-Jie TANG, Si-Fa LI, Wan-Qi CAI, Yan ZHAO

In the present study, the genetic diversity of one selected strain (Pujiang No. 1), two domesticated populations (GA and HX) and four wild populations (LZ, YN, SS and JL) of blunt snout bream (Megalobrama amblycephala) was analyzed using 17 microsatellite markers. The results showed that an average of 4.88-7.65 number of alleles (A); an average of 3.20-5.33 effective alleles (N_e); average observed heterozygosity (H_o) of 0.6985-0.9044; average expected heterozygosity (H_e) of 0.6501-0.7805; and the average polymorphism information content (PIC) at 0.5706-0.7226. Pairwise F_ST value between populations ranged from 0.0307-0.1451, and Nei's standard genetic distance between populations was 0.0938-0.4524. The expected heterozygosities in the domesticated populations (GA and HX) were significantly lower than those found in three wild populations (LZ, SS and JL), but no difference was detected when compared with the wild YN population. Likewise, no difference was found between the four wild populations or two domesticated populations. The expected heterozygosity in Pujiang No. 1 was higher than the two domesticated populations and lower than the four wild populations. Regarding pairwise F_ST value between populations, permutation test P-values were significant between the GA, HX and PJ populations, but not between the four wild populations. These results showed that the expected heterozygosity in the selected strain of blunt snout bream, after seven generations of selective breeding, was lower than that of wild populations, but this strain retains higher levels of genetic diversity than domesticated populations. The genetic differences and differentiation amongst wild populations, domesticated populations and the genetically improved strain of blunt snout bream will provide important conservation criteria and guide the utilization of germplasm resources.

124-131

Authors: Xiao-Li FAN, Zhi-Hua LIN, Jie WEI

While developmental plasticity can facilitate evolutionary diversification of organisms, the effects of water levels as an environmental pressure on tiger frogs remains unclear. This study clarifies the relationship by studying the responses of tiger frog (Hoplobatrachus chinensis) tadpoles to simulated hydroperiods (i.e., constant low water levels, constant high water levels, increasing water levels, decreasing water levels, rapid changes in water levels and gradual fluctuations in water levels) in a laboratory setting. ANOVA analysis showed that none of the water level treatments had any significant effect on the total length, body mass, or developmental stages of H. chinensis tadpoles half way through development (11 days old). Tadpoles raised in rapidly fluctuating water levels had protracted metamorphosis, whereas tadpoles raised under low and gradually fluctuating water levels had shortened metamorphosis. None of the water level treatments had a significant effect on the snout-vent length (SVL) or body mass of H. chinensis tadpoles at Gosner stage 42, or on the body mass of tadpoles at Gosner stage 45. However, the tadpoles raised in high levels and rapidly fluctuating water levels, significantly larger SVL at Gosner stage 45, while ones under gradually fluctuating water levels had smaller SVL than the other groups. Time to metamorphosis was positively correlated with body size (SVL) at metamorphosis in H. chinensis tadpoles. H. chinensis tadpoles under constant low water level had the highest mortality rate among all the treatments (G-test). Moreover, ANOVA and ACNOVA (with body length as the covariate) indicated that water levels had no significant effect on either the morphology (i.e. head length, head width, forelimb length, hindlimb length and body width) or the jumping ability of juvenile H. chinensis. These results suggest that the observed accelerated metamorphosis and high mortality of H. chinensis tadpoles under decreasing water level treatment was driven by density-induced physical interactions among increasing conspecifics.

142-159

Authors: Marco Endruweit

Selected, little known taxa of northern and central Vietnamese freshwater fish species are reviewed. Nomenclatural acts are taken: Hemibarbus lehoai is placed in synonymy of H. maculatus, Paracobitis hagiangensis in synonymy of Schistura caudofurca. A neotype of Micronemacheilus bacmeensis is assigned. The name Channa hanamensis is treated as a nomen nudum. Two labeonine species described from China are nomenclaturally affected: Garra findolabium is transferred to Vinagarra and its specific epithet is treated as a noun in apposition; the specific epithet of Sinigarra napoense is corrected to napoensis.

20-32

Authors: Wei-Ying WANG, Wei ZHOU, Jun-Xing YANG, Xiao-Yong CHEN

Garra imberba is widely distributed in China. At the moment, both Garra yiliangensis and G. hainanensis are treated as valid species, but they were initially named as a subspecies of G. pingi, a junior synonym of G. imberba. Garra alticorpora and G. nujiangensis also have similar morphological characters to G. imberba, but the taxonomic statuses and phylogenetic relationships of these species with G. imberba remains uncertain. In this study, 128 samples from the Jinshajiang, Red, Nanpanjiang, Lancangjiang, Nujiang Rivers as well as Hainan Island were measured while 1 mitochondrial gene and 1 nuclear intron of 24 samples were sequenced to explore the phylogenetic relationship of these five species. The results showed that G. hainanensis, G. yiliangensis, G. alticorpora and G. imberba are the same species with G. imberba being the valid species name, while G. nujiangensis is a valid species in and of itself.

42-50

Authors: Yi-Lin ZHOU, Xia QIU, Xiao-Bin FANG, Lu-Yi YANG, Yi ZHAO, Teng FANG, Wei-Hong ZHENG, Jin-Song LIU

Anurans often have species-specific vocalizations. To quantify and compare the characteristics of anuran calls in Gutianshan National Nature Reserve, Zhejiang Province, we recorded the advertisement calls of eight species belonging to four families (Ranidae, Microhylidae, Megophryidae and Bufonidae) from June to September 2012 using Sony ICD-FX8 IC recorders. All recordings were analyzed using the "Praat" software. Five acoustics parameters were measured, including temporal traits (call duration, number of notes or pulse number/call) and spectral traits (fundamental frequency, the first three formants and dominant frequency). The characteristic parameters of Microhyla ornate and Fejervarya limnocharis calls were different as were the calls of some populations of the same species recorded in different regions. The advertisement calls of the eight species were specific. Our study has provided a useful reference for identifying the calls of some common Chinese anurans.

59-66

Authors: Marco Endruweit

An ichthyofaunistic survey of Mekong tributaries in Lincang Prefecture, Yunnan Province, China yielded a new species of nemacheilid loach, herein described as Schistura sexnubes species nova. The new species is readily distinguishable from its congeners by the following combination of characters: 8+8 branched caudal fin rays, an incomplete lateral line, a dissociated caudal bar, a shallow caudal peduncle depth (7.6%-9.6% SL; respectively caudal peduncle 1.76-1.95 times longer than deep), a diminutive size of less than 50 mm SL, and no sexual dimorphism. A dorsocephalic pattern consisting of a black, forward directed V-shaped formation located between the nares, and a white, ovoid blotch on the upper operculum serves as an autapomorphy.

72-74

Authors: Hong-Yu TIAN, Xiao-Feng ZHU, Yu-Xi DUAN, Li-Jie CHEN

From 2011 to 2012, we collected Scutellonema commune from the rhizosphere soil of coconut (cocos nucifera L.) and Scutellonema magniphasma from the rhizosphere soil of Rosa chinensis in Shenyang, China. S. commune was characterized by rounded scutella, which was varied from two annules anterior to the anus and five annules posterior. The lateral field was not areolated at the level of scutella. S. magniphasma was characterized by varying scutellum, about 7.0 µm in diameter, in position from four annules posterior to four annules anterior to the anus, and areolated at the level of the scutellum.