Are 6‐month‐old foals sensitive to dam's influence?

A recent study has shown that gently handling dams in front of their few days old foals may strongly influence the development of human-foal relationships. In the present study, we test whether 6-month-old foals remain sensitive to their dams' influence. The study was performed on 16 foal-mare dyads, with half of the mares receiving positive contacts from the experimenter in presence of their 6-month-old foals (n = 8) whereas the other mares were not handled (n = 8). All foals were tested 15 and 30-35 days later under various conditions (reaction to a motionless human, approach test, saddle-pad tolerance test). We observe a positive effect of mare' handling on foals' reactions to humans but with a high interindividual variability, suggesting a higher effect of the foals' own behavioral characteristics at this age than at earlier stages.     

The incidence of combined facial and cervical spine injuries

BACKGROUND: The association between facial and cervical spine injuries has been documented. However, only severe spinal injuries were included in previous analyses. It was the purpose of this study to evaluate the incidence of and risk factors for these injury combinations including the complete injury spectrum. METHODS: Between 1995 and 1997, 4,907 patients with cervical spine injuries were treated at our hospital. One hundred five (2.14%) of these patients had suffered a concomitant facial injury. This group was compared with the group of patients with cervical spine injury but without facial trauma. RESULTS: The majority of cases (98%) consisted of minor lesions to both regions. With increasing severity of cervical spine trauma, the risk for facial injury increased. Age and male gender represent significant (p < 0.05) risk factors for combined injuries. CONCLUSION: Patients sustaining cervical spine trauma have a small but real chance of injuring their face as well. The cervical spine must be examined carefully, whenever facial injuries are present.     

Hemispheric specialization in the primary auditory area of awake and anesthetized starlings (Sturnus vulgaris)

Although evidence exists for a lateralization of song production, few studies have focused on the perceptual aspect of lateralization in songbirds. In the present study, the authors recorded neuronal responses to a variety of species-specific and artificial, nonspecific stimuli in both hemispheres of awake and anesthetized male starlings (Sturnus vulgaris). Recordings were made in the primary auditory area of the songbird brain, the Field L complex. The right hemisphere exhibited significantly more responsive units than the left hemisphere in awake birds, and this difference was significantly reduced in anesthetized birds. Furthermore, clear hemispheric specialization toward categories of behaviorally relevant stimuli and precise parameters of these stimuli were found. The main auditory area of the starling's brain thus appears to show some degree of lateralization.     

Seasonal female brain plasticity in processing social vs. sexual vocal signals

While cerebral plasticity has been extensively studied and demonstrated – during ontogenetic development, few studies have considered adult plasticity in different social contexts using relevant social communication signals. Communication requires adaptability throughout the life of an individual, especially in species for which breeding periods (when intersexual signaling prevails) are interspersed with more ‘social’ (non‐sexual) periods when intrasexual bonding prevails. In songbirds, structure or frequency of songs or song elements may convey different information depending on the season. This is the case in the European starling, where some song structures characterize social bonds between females while other song structures are more characteristic of male courtship. We hypothesized that the female perceptual system may have adapted to these changes in song structure and function according to season, and we tested for potential seasonal brain plasticity. Electrophysiological recordings from adult female starlings during playback of song elements with different functions showed clear seasonal (breeding/non‐breeding) changes in neuronal responses in the primary auditory area. The proportion of responsive sites was higher in response to social (non‐sexual) songs during the non‐reproductive season, and higher in response to sexual songs during the reproductive season.     

Die Glykogenablagerung in Leber,Muskel und Fettgewebe hungernder Ratten nach Glukosefütterung

Zusammenfassung An Ratten, die 6 Std bis 8 Tage gehungert hatten, wurde untersucht, ob mit zunehmender Hungerdauer die Fähigkeit zur Glykogenablagerung in der Leber, der Skeletmuskulatur und im Fettgewebe nach oraler Glukosegabe sich vermindert. Eine Wirkung des Hungers auf die Glykogenspeicherung konnte nicht festgestellt werden. Der Grund der Hemmung der Glykogenbildung bei früheren Versuchen in vitro wird in der Anwesenheit von hemmenden hypophysären Wirkstoffen — entsprechend beim Diabetes — angenommen, die bei der Fütterung im lebenden Tier in kurzer Zeit unwirksam werden, dagegen bei den Versuchen in vitro ihre Wirkung weiter entfalten.     

Influence of various early human-foal interferences on subsequent human-foal relationship

Whereas the way animals perceive human contact has been particularly examined in pet animals, a small amount of investigations has been done in domestic ungulates. It was nevertheless assumed that, as pet animals, non-aggressive forms of tactile contact were as well rewarding or positive for these species, even though the features of intraspecific relationships in pet animals and domestic ungulates may be to some extent different.We test here the hypothesis that horses may not consider physical handling by humans as a positive event. When comparing different early human-foal interactions, we found that early exposure to a motionless human enhanced slightly foals reactions to humans whereas forced stroking or handling in early life did not improve later human-foal relation. Foals that were assisted during their first suckling (e.g., brought to the dam's teat) even tended to avoid human approach at 2 weeks, and physical contact at 1 month of age.We argue that interspecies differences may exist in how tactile stimulation is perceived. It may be important for the establishment of a bond that a young animal is active in the process and able, through its behavioral responses, to help define what is positive for it. This way of investigation may have important general implications in how we consider the development of social relations, both within and between species.