Leptospirosis with multiple organ dysfunction in a mongoose-scat-detection dog infected with Leptospira interrogans serogroup Hebdomadis, Okinawa, Japan.

A 2-year-old male mongoose-scat-detection dog was diagnosed with leptospirosis by urine PCR. The patient developed acute renal failure, hepatic dysfunction, and disseminated intravascular coagulation. Treatment with antibiotics was administered, including ampicillin and doxycycline, and supportive care management was provided. Seroconversion against serogroup Hebdomadis was observed on day 8. The leptospiral gene flaB was detected only in urine collected on day 1, from which Leptospira interrogans ST329 was identified by multilocus sequence typing using seven housekeeping genes. L. interrogans serogroup Hebdomadis ST329 has been isolated from mongooses and humans in Okinawa, Japan. This patient received early treatment with antibiotics, which may have contributed to the early recovery of renal function and removal of L. interrogans from kidney tissue.

Immature male gibbons produce female-specific songs.

Gibbons are apes that are well known to produce characteristic species-specific loud calls, referred to as "songs." Of particular interest is the sex specificity of the "great calls" heard in gibbon songs. However, little is known about the development of such calls. While great calls are given by female gibbons of various ages, they have never been recorded from males. Here, we report two observations of immature male gibbons from two different species, wild Hylobates agilis and captive H. lar, which spontaneously sang female-specific great calls. Based on the video clips, we conclude that immature males also have the potential to produce great calls. Our observations led us to propose a new hypothesis for the development of sexual differentiation in the songs of gibbons, and its implications for the general issue of sex-specific behavior in primates.

Individual difference in serum oxytocin concentrations of calves and the correlation with those in dams.

We examined individual differences in serum oxytocin concentrations (OT) of calves, and assessed whether these differences were correlated with their dams' milk and serum OT. Eight Holstein (H), nine Japanese Shorthorn (JS), and six Japanese Black (JB) calves were examined. Blood was collected three times during the first month in H calves, while their dams' blood was collected three times prior to parturition. Milk was collected twice after parturition from H cows. Blood from JS and JB calves were collected at 1 and 4 months old, while of their dams only once before parturition. Serum OT in H calves at 7 days old was significantly correlated with that at 30 days. Serum OT of JS calves at 1 month old was significantly correlated to that at 4 months, while of JB calves was also positively correlated (r = 0.70). Serum OT of calves showed significant individual differences in each breed. Serum OT of calves was not correlated with the milk OT of dams, except for 3-day-old calves that fed on their dams' milk. We concluded that although serum OT differed among individuals, this difference was stable within each individual and not affected by the serum OT of the dams.

Possible role of mother-daughter vocal interactions on the development of species-specific song in gibbons.

Mother-infant vocal interactions play a crucial role in the development of human language. However, comparatively little is known about the maternal role during vocal development in nonhuman primates. Here, we report the first evidence of mother-daughter vocal interactions contributing to vocal development in gibbons, a singing and monogamous ape species. Gibbons are well known for their species-specific duets sung between mates, yet little is known about the role of intergenerational duets in gibbon song development. We observed singing interactions between free-ranging mothers and their sub-adult daughters prior to emigration. Daughters sang simultaneously with their mothers at different rates. First, we observed significant acoustic variation between daughters. Co-singing rates between mother and daughter were negatively correlated with the temporal precision of the song's synchronization. In addition, songs of daughters who co-sang less with their mothers were acoustically more similar to the maternal song than any other adult female's song. All variables have been reported to be influenced by social relationships of pairs. Therefore those correlations would be mediated by mother-daughter social relationship, which would be modifiable in daughter's development. Here we hypothesized that daughters who co-sing less often, well-synchronize, and converge acoustically with the maternal acoustic pattern would be at a more advanced stage of social independence in sub-adult females prior to emigration. Second, we observed acoustic matching between mothers and daughters when co-singing, suggesting short-term vocal flexibility. Third, we found that mothers adjusted songs to a more stereotyped pattern when co-singing than when singing alone. This vocal adjustment was stronger for mothers with daughters who co-sang less. These results indicate the presence of socially mediated vocal flexibility in gibbon sub-adults and adults, and that mother-daughter co-singing interactions may enhance vocal development. More comparative work, notably longitudinal and experimental, is now needed to clarify maternal roles during song development.

Soprano singing in gibbons.

Diversifications in primate vocalization, including human speech, are believed to reflect evolutionary modifications in vocal anatomy and physiology. Gibbon song is acoustically unique, comprising loud, melodious, penetrating pure tone-like calls. In a white-handed gibbon, Hylobates lar, the fundamental frequency (f(0) ) of song sounds is amplified distinctively from the higher harmonics in normal air. In a helium-enriched atmosphere, f(0) does not shift, but it is significantly suppressed and 2f(0) is emphasized. This implies that the source is independent of the resonance filter of the supralaryngeal vocal tract (SVT) in gibbons, in contrast to musical wind instruments, in which the filter primarily determines f(0) . Acoustic simulation further supported that gibbons' singing is produced analogously to professional human soprano singing, in which a precise tuning of the first formant (F(1) ) of the SVT to f(0) amplifies exclusively the f(0) component of the source. Thus, in gibbons, as in humans, dynamic control over the vocal tract configuration, rather than anatomical modifications, has been a dominant factor in determining call structure. The varied dynamic movements were adopted in response to unique social and ecological pressures in gibbons, allowing monogamous gibbons to produce pure-tonal melodious songs in the dense tropical forests with poor visibility.

Male replacement and stability of territorial boundary in a group of agile gibbons (Hylobates agilis agilis) in West Sumatra, Indonesia.

We report membership change in a group of wild agile gibbons, Hylobates agilis agilis, in West Sumatra, Indonesia. During 6-month observational periods, we focused on a particular unit of individuals known as the B group. We confirmed that the group consisted of five individuals: one adult female, one adult male, one subadult male, one subadult female, and one infant male. During our observations, the resident adult male and the two subadult individuals dispersed or disappeared, and a new adult male took over the group. We examined the effects of the male replacement on the territorial boundary, using the auditory census technique. The boundary was stable. We also documented the succession of the home range. Our results indicate a flexible social structure in this species and contribute some useful data to an ongoing debate on their social dynamics.

Influence of sound specificity and familiarity on Japanese macaques' (Macaca fuscata) auditory laterality.

Despite attempts to generalise the left hemisphere-speech association of humans to animal communication, the debate remains open. More studies on primates are needed to explore the potential effects of sound specificity and familiarity. Familiar and non-familiar nonhuman primate contact calls, bird calls and non-biological sounds were broadcast to Japanese macaques. Macaques turned their heads preferentially towards the left (right hemisphere) when hearing conspecific or familiar primates supporting hemispheric specialisation. Our results support the role of experience in brain organisation and the importance of social factors to understand laterality evolution.

Acoustic features contributing to the individuality of wild agile gibbon (Hylobates agilis agilis) songs.

We examined acoustic individuality in wild agile gibbon Hylobates agilis agilis and determined the acoustic variables that contribute to individual discrimination using multivariate analyses. We recorded 125 female-specific songs (great calls) from six groups in west Sumatra and measured 58 acoustic variables for each great call. We performed principal component analysis to summarize the 58 variables into six acoustic principal components (PCs). Generally, each PC corresponded to a part of the great call. Significant individual differences were found across six individual gibbons in each of the six PCs. Moreover, strong acoustic individuality was found in the introductory and climax parts of the great call. In contrast, the terminal part contributed little to individual identification. Discriminant analysis showed that these PCs contributed to individual discrimination with high repeatability. Although we cannot conclude that agile gibbon use these acoustic components for individual discrimination, they are potential candidates for individual recognition.