Is the Dairy Cow Performing to Bite Grasses Comfortable in Grazing? (Advanced Studies on Sustainable Animal Production: Interrelationships among Human, Animal and Environment, 8th International Symposium of Integrated Field Science)

Poster Sessio

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

ヤセイ アジルテナガザル ニ オケル シュ トクイテキ オンセイ ノ コタイセイ ヤ チイキセイ オ ウミダス メカニズム ノ カイメイ

京都大学0048新制・課程博士博士(理学)甲第14035号理博第3328号新制||理||1491(附属図書館)UT51-2008-F427京都大学大学院理学研究科生物科学専攻(主査)教授 正高 信男, 教授 渡邊 邦夫, 准教授 西村 剛学位規則第4条第1項該当Doctor of ScienceKyoto UniversityDA

Mother-Offspring overlapping duetting in gibbons

International audienceDuetting is a special form of singing interaction occurring in many animal species, and is generally defined as overlapping bouts of antiphonal or synchronous vocalizations by paired adult individuals or potential mates. Here, we document evidence of another type of overlapping song interaction between adult females and their offspring, that is, mother-offspring overlapping duetting. Our observations of three gibbon species indicated that immature offspring rarely produce vocalizations alone but vocalize to overlap their calls with the female-specific elaborate songs of their mothers. The call-onset time lags of overlapping calls between mother and offspring were stable, and the overlapping interactions were highly synchronised. Thus, these overlapping songs can be considered another form of duetting. Herein, we describe mother-offspring duetting and proposed the secondary function found only in gibbon duetting that would facilitate strong acoustical attachment during mother-offspring bonding

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

Effect of Environmental Enrichment on the Behavior and Welfare of Japanese Broilers at a Commercial Farm

The effect of hay bales and perches as environmental enrichment material was investigated on the behavior, heterophil/lymphocyte (H/L) ratio, footpad dermatitis (FPD), and productivity of Japanese broilers in a commercial farm. About 21,500 birds were allocated to 4 houses: male versus female×control versus treatment house. We observed maintenance behavior, the utilization of hay bales and perches, and the H/L ratio of birds at 3, 5, and 8 weeks of age. FPD was scored and productivity was calculated at about 60 days after hatching. Compared to birds in the control houses, birds in the treatment houses invested more time in stand-resting and moving behaviors (P<0.01, for each behavior) and less time feeding, drinking, and sit-resting (P<0.01, for each behavior). Females used the hay bales and perches more than the males (P<0.1 and P<0.01, respectively). The activity and utilization of hay bales and perches decreased with age (P<0.01, for each behavior, respectively). The H/L ratio of birds in the treatment houses was lower than that in the control houses (P<0.01). The prevalence of FPD was milder in the treatment houses compared to the control houses for females (P<0.01), but not for males. In conclusion, hay bales and perches represent effective enrichment materials, allowing broilers to express normal behavior, alleviating stress in the younger and lighter birds of both sexes, and reducing FPD in female birds using the hay bales and perches more than males

Possible Role of Mother-Daughter Vocal Interactions on the Development of Species-Specific Song in Gibbons

International audienceMother-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

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

International audienceDespite 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

Co-singing rates of daughter and maternal preceding rates.

1<p>Mother sung great calls with daughters (co-singing) or without daughter (solo singing). Therefore, those numbers are summations of both singing patterns. Solo great calls were used in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0071432#pone-0071432-g005" target="_blank">Figure 5</a>.</p>2<p>Because the great call is a long series of multiple calls lasting approximately 10 sec, we could readily identify the occurrence of co-singing; however, the onsets of two great calls were difficult to determine in some cases because of background noise and were considered non-analyzable.</p

Map of Sumatra, Borneo and Malay Peninsula, illustrating the geographic range of agile gibbons (grey area).

<p>Star shows the location of our study site (0°54’S, 100°28’E, Limau Manis, Sumatra, Indonesia).</p