Pairing and physical confrontation in adult sows causes social stress reactions and aggressive behaviors. Recently, maternal pig skin secretions were isolated and a mixture containing several fatty acids, now called pig appeasing pheromone (PAP), was synthesized. In this study, we investigated the effects of PAP on social and immune stress response in adult female miniature pigs. PAP or vehicle solvents were sprayed into the pens of individually housed adult sows. A two-week exposure to the pheromone did not alter basal salivary cortisol levels or circadian rhythms. Following this treatment, the animals were paired and placed in a new pen that was divided with a wire-mesh fence. Although salivary cortisol increased markedly in the vehicle-treated group, the PAP-treated group exhibited a drastic inhibition of cortisol secretion. This effect was sustained even after they were allowed to physically interact following fence removal. Moreover, the latency time of agonistic behaviors, such as escaping or biting, was significantly extended after PAP exposure. When lipopolysaccharide was injected intramuscularly, cortisol levels, rectal temperatures, and lying time lengths increased substantially. No differences were observed between the pheromone-treated and untreated groups. These results suggest that this synthetic pheromone alleviates social stress in adult pigs, although it does not affect immune stress responses. Our findings demonstrate the potential benefit of this pheromone in field applications and clinical disciplines relating to adult female pigs.

Chromosomes of the dinoflagellate Oxyrrhis marina are composed of thin parallel filaments running longitudinally and lack the arched structure common to the dinochromosome. The physicochemical and molecular organization of these chromosomes, including the localization and arrangement of genes, is still unknown. We investigated the locations of three protein-coding genes, actin (AF482402), α-tubulin (AF482403), and HSP90 (AY391258), on these chromosomes using fluorescence in-situ hybridization (FISH). Primers for these three genes were designated according to known partial sequences. PCR products amplified from total DNA were labeled with digoxigenin (DIG) by random priming and used as probes. After in-situ hybridization, DIG signals were amplified and visualized with anti-DIG-FITC. The number of signals was 3±1.3 (n=90) for actin, 4.1±1.4 (n=70) for α-tubulin, and 5.5±1.7 (n=80) for HSP90. This study is the first to locate protein-coding genes in the nucleus of a dinoflagellate, although the chromosomes were greatly damaged during the FISH process. The copy number of each gene per cell was estimated using real time PCR. Resulting copy numbers of actin, α-tubulin and HSP90 were, 33.7, 10.4 and 5.4, respectively.

In the majority of invertebrate and vertebrate species, gametogenesis starts with the formation of cysts (clusters) of sibling germline cells. Cysts originate as the result of mitotic divisions of a specialized germline cell, the cystoblast. Since these divisions are incomplete, the cyst cells (cystocytes) remain connected by stable connections, termed intercellular bridges (ring canals). In forficuloid earwigs, female germ cell cysts are composed of two cells only: the pro-oocte and pro-nurse cells. We show that in Opisthocosmia silvestris, the cystoblast, as well as both cells of the cyst, contain the Balbiani body (Bb), a distinct cytoplasmic organelle composed of numerous mitochondria. We also show that in the cyst cells, the Bbs are invariably located next to the fusome, a specialized cytoplasm occupying the bridge connecting sibling cells.

Butterfly wing color patterns can be changed by the application of a temperature shock or pharmacological agents such as tungstate, producing a distinctive type of elemental modification called the TS (temperature shock) type. Heterochronic uncoupling between the signaling and reception steps during the color-pattern determination process has been proposed as a mechanism for TS-type changes. As an extension of this hypothesis, both the parafocal element (PFE) and the eyespot in the same wing compartment are considered to be determined by morphogenic signal(s) emitted from the same eyespot focus. However, these models need to be examined with additional experimental data. Furthermore, there is controversy as to whether the action of tungstate on wing color patterns is direct or indirect. Using a species of nymphalid butterfly (Junonia orithya), we have devised a simple method for the local application of pharmacological agents directly on developing wings of pupae. Local tungstate application resulted in reduced eyespots and circular dislocated PFEs in the eyespot-less compartments only on the treated wing, demonstrating that tungstate directly induces color-pattern changes on wings. We further examined the eyespot-PFE relationship in normal and cold-shocked individuals, showing that an eyespot can be superimposed on a PFE and vice versa, probably depending on the timing of their fate determination. Taken together, we propose a two-morphogen model for the normal color-pattern determination, in which the morphogenic signals for the eyespot and PFE are different from each other despite their identical origin. This two-morphogen model is compatible with the heterochronic uncoupling model for TS-type changes.

Mitochondrial DNA (mtDNA) D-loop control region sequences ranging in length from 583 to 598 bp were determined for eight Japanese wolf specimens (Canis lupus hodophilax Temminck, 1839) collected from several sites and compared with 105 haplotypes from the domestic dog (C. lupus familiaris) and continental grey wolf (C. lupus lupus). Also, a 197-bp mtDNA sequence was amplified from archaeological wolf specimens and two continental wolf specimens (C. lupus chanco) as reference sequences for analysis. The mtDNA haplotypes from the eight Japanese wolf specimens were closely related to each other and grouped in a single lineage with an 88% bootstrap value in a neighbor-joining analysis. The results provide valuable information for understanding the taxonomic and phylogenetic relationships of the Japanese wolf, which have long been controversial.

We show that the learned vocalizations of male and female large-billed crows (Corvus macrorhynchos) are similar and that their functions and physical features show significant differences from those of other oscine species. We investigate whether the song control nuclei of crows show any sexual differences in size, reflecting differences in their singing behavior, and whether these nuclei are different from those of other songbirds in terms of neural connectivity size and relative to the forebrain. Our Nissl staining results reveal that 1) of the four song nuclei examined (HVC; the robust nucleus of the arcopallium [RA]; Area X; and the dorsolateral medial nucleus [DLM]), HVC, RA, and Area X volumes are significantly larger in males than in females, but DLM volume and body and brain weights show no significant gender differences; and 2) the sizes of song nuclei relative to the forebrain are within the range of other oscines. By injecting a neural tract tracer (DiI) into various song nuclei in brain slices, we found that, as in other songbirds, HVC projects to RA and Area X, while Area X projects to the lateral magnocellular nucleus of the anterior nidopallium (lMAN) and DLM, DLM to lMAN, and lMAN to RA. Our results indicate that, although the crow has songs very different from those of other oscine species, its song nuclei and the connections between them are not obviously different.

We propose that amino acids in natal stream water have important roles in Pacific salmon homing. This study hypothesized that amino acids found in natal stream water have a role in the ability of mature male chum salmon (Oncorhynchus keta) to home to the Osaru River (OR), Hokkaido, Japan. Behavioral experiments were conducted in a two-choice test tank using various combinations of control water (natural Toya Lake water; NLW and three artificial stream waters using amino acids: 1) artificial OR water (AOR); 2) AOR without L-glutamic acid, the major amino acid in OR water (AOR-E); and 3) artificial water matching another stream (ALS) that had much higher amino acid concentrations than OR. In behavioral tests, the fish did not select between AOR and AOR-E, but still chose AOR over NLW, AOR-E over NLW, and AOR over ALS. These results suggest that migratory male chum salmon respond to amino acid mixtures in their natal stream water and appear to be affected by multiple amino acids.

Isolation and characterization of genes specifically expressed in ovaries are necessary for understanding sex differentiation and ovarian development processes in the giant tiger shrimp, Penaeus monodon. In this study, a transcript that significantly matched the polehole precursor was further characterized by RACE-PCR. The sequence obtained was 5151 bp in length and contained a coding region of 5031 bp corresponding to 1677 amino acids. This transcript was only expressed in ovaries but not in testes of juveniles (N=10) and broodstock (N=22) of P. monodon. A tissue distribution analysis further confirmed ovary-specific expression of this transcript (called P. monodon ovary-specific transcript 1, Pm-OST1) in female broodstock. Expression levels of Pm-OST 1 in ovaries of juvenile P. monodon upon 5-HT injection (33.9±6.40 g; 50 µg/g body weight) were significantly higher at 12–72 hours post injection (P<0.05). Quantitative real-time PCR indicated that Pm-OST1 was comparably expressed throughout ovarian development in normal P. monodon broodstock (P>0.05). However, the expression level of Pm-OST1 was significantly higher in stage-III ovaries in eyestalk-ablated broodstock (P<0.05). Pm-OST1 was clearly localized in the ooplasm of previtellogenic and vitellogenic oocytes. Our results suggest that Pm-OST1 plays a functionally important role in promoting the development of female germ cells and oocytes in P. monodon.

We report the karyotypes of six species of the order Soricomorpha (Mammalia), based on specimens collected from Emei Shan (Mount Emei) in central Sichuan Province, China: two talpid species, Uropsilus andersoni (diploid chromosome number [2n]=34, fundamental number of chromosome arms including two X chromosomes [FN]=56) and Scaptonyx fusicaudus (2n=34, FN=64); and four soricid species, Episoriculus sacratus (2n=58, FN=108), Anourosorex squamipes (2n=48, FN=96), Sorex cylindricauda (2n=30, FN=50), and Sorex bedfordiae (2n=24/25, FN=46/48). This is the first report of the karyotypes of all species except Sc. fusicaudus and A. squamipes. Episoriculus sacratus is considered to be a valid species in Sichuan, separated from the Nepalese E. soluensis based on differences in the karyotype. The karyotype of S. bedfordiae showed polymorphism due to the occurrence of a B chromosome. Differences in the karyotypes of S. cylindricauda and S. bedfordiae could be explained mostly by seven Robertsonian translocations revealed by G-band karyotypes.

We recorded the nereidid polychaete Leonnates persicus Wesenberg-Lund, 1949, previously known from coasts of Indian Ocean and western Pacific Ocean, from the coasts of Japan, Korea, and Thailand, based on examination of 27 specimens collected from shallow subtidal or intertidal muddy flats at 16 localities. The morphological characteristics of this material agreed well with those of the holotype from the Persian Gulf. We describe some important new characteristics of the holotype, which had not been appropriately described in previous literature.