Abstract: The basolateral amygdala (BLA) has a crucial role in emotional learning irrespective of valence1, 2, 3, 4, 5, 21, 22, 23. The BLA projection to the nucleus accumbens (NAc) is thought to modulate cue-triggered motivated behaviours4, 6, 7, 24, 25, but our understanding of the interaction between these two brain regions has been limited by the inability to manipulate neural-circuit elements of this pathway selectively during behaviour. To circumvent this limitation, we used in vivo optogenetic stimulation or inhibition of glutamatergic fibres from the BLA to the NAc, coupled with intracranial pharmacology and ex vivo electrophysiology. Here we show that optical stimulation of the pathway from the BLA to the NAc in mice reinforces behavioural responding to earn additional optical stimulation of these synaptic inputs. Optical stimulation of these glutamatergic fibres required intra-NAc dopamine D1-type receptor signalling, but not D2-type receptor signalling. Brief optical inhibition of fibres from the BLA to the NAc reduced cue-evoked intake of sucrose, demonstrating an important role of this specific pathway in controlling naturally occurring reward-related behaviour. Moreover, although optical stimulation of glutamatergic fibres from the medial prefrontal cortex to the NAc also elicited reliable excitatory synaptic responses, optical self-stimulation behaviour was not observed by activation of this pathway. These data indicate that whereas the BLA is important for processing both positive and negative affect, the glutamatergic pathway from the BLA to the NAc, in conjunction with dopamine signalling in the NAc, promotes motivated behavioural responding. Thus, optogenetic manipulation of anatomically distinct synaptic inputs to the NAc reveals functionally distinct properties of these inputs in controlling reward-seeking behaviours.

Abstract: In der Zeit von April 2005 bis März 2006 wurden bei 105 Pferden monatlich
koprologische Untersuchungen durchgeführt. Die Pferde waren zu zwei Drittel
Jungtiere (≤ 4 Jahre) und ein Drittel > 4 Jahre. Die zur Verfügung stehenden vier
Betriebe befanden sich alle im Raum Baden-Württemberg.
Die Kotproben wurden mit Hilfe der Flotation auf Magen-Darmnematoden untersucht
und anschließend einer quantitativen Eizahlbestimmung nach Mc Master unterzogen.
Ab einem Eigehalt von 250 Eiern pro Gramm Kot (EpG) wurden die Pferde
entsprechend der Gruppenzugehörigkeit entweder mit Pyrantel oder Ivermectin
behandelt.
Es wurden bei 73 Pferden ausschließlich Strongylideneier nachgewiesen; bei vier
Pferden waren in der Flotation zusätzlich Eier von Parascaris equorum zu finden.
Bei 28 (26,7%) der untersuchten Pferde wurden in keiner der 12 untersuchten
Proben Eier von Magen-Darmnematoden nachgewiesen. Insgesamt mussten
57 (54,3%) der Pferde über den gesamten Untersuchungszeitraum hinweg nicht
behandelt werden. 48 (45,7%) Pferde mussten mindestens einmal anthelminthisch
behandelt werden. Kein Pferd musste häufiger als dreimal behandelt werden.
In den Monaten August bis November war der Anteil an positiven Proben der
Jungtiere signifikant höher als bei den Pferden > 4 Jahre. Innerhalb der
Jungtiergruppe nahm die Höhe der Strongyliden-Eiausscheidung mit zunehmendem
Alter signifikant ab.
Ebenso nahm die Anzahl der positiven Proben im Laufe des
Untersuchungszeitraums signifikant ab.
Die beiden zur Entwurmung eingesetzten Substanzen (Pyrantel und Ivermectin)
waren voll wirksam. In 98,8% der untersuchten Proben war ein Rückgang der
Ei-Ausscheidung noch vier Wochen nach der Behandlung auf 0 EpG nachweisbar,
d. h. es gab keinerlei Anzeichen für das Vorliegen von Resistenzen gegen die
eingesetzten Substanzen.
Die vorliegenden Untersuchungen sind ein weiterer Beweis dafür, dass mit Hilfe der
selektiven anthelminthischen Behandlung die Anzahl der Entwurmungen –
insbesondere auch bei Jungtieren – deutlich gesenkt werden kann.
Die Eiausscheidung und damit die Weidekontamination werden mit Hilfe dieses
Verfahrens deutlich reduziert.
[Between April 2005 and March 2006 monthly koprological examinations where
carried out on 105 horses.
Two third of the horses were young animals (≤ 4 years) and a third were > 4 years
old.
The four farms on hand were all located in the Baden- Württemberg area.
Faecal samples were examined for gastro-intestinal nematodes by means of flotation
and subsequently subjected to an egg-quantity counting according to Mc Master.
Starting from an egg content of 250 eggs per gram faeces (EpG), the horses were
treated with either Pyrantel or Ivermectin according to their group affiliation.
In 73 horses solely Strongyle eggs were detected; the flotation of four horses
additionaly showed eggs of Parascaris equorum.
In 28 (26,7%) of the examined horses none of the 12 examined samples showed
eggs of gastro-intestinal nematodes.
Overall 57 (54,3%) horses didn´t need any treatment during the total examination
cycle. 48 (45,7%) of the horses needed at least one anthelminthic treatment.
None of the horses needed to be treated more than three times.
From August to November the rate of positive samples within the group of young
animals was significantly higher than in the horses > 4 years.
Whithin the group of young animals the level of Strongyle egg excretions dropped
significantly with advancing age.
Likewise, the number of positive samples also dropped significantly in the course of
the examination cycle.
Both substances (Pyrantel and Ivermectin) applied for deworming were fully effective.
Even a further 4 weeks after treatment the examined sample showed a drop of egg
excretion to 0 EpG in 98,8% of the samples, in other words there were no signs of
prevailing resistance appearances towards the applied substance.
The present studies are further proof that the number of dewormings-especially in
young animals can be distinctly reduced by means of selective anthelminthic
treatments.
Egg excretion and therewith pasture land contamination can be clearly reduced by
means of this procedure.]

Abstract: In apes, four criteria are set to explore referential and intentional communication: (1) successive visual orienting between a partner and distant targets, (2) the presence of apparent attention-getting behaviours, (3) the requirement of an audience to exhibit the behaviours, and (4) the influence of the direction of attention of an observer on the behaviours. The present study aimed at identifying these criteria in behaviours used by dogs in communicative episodes with their owner when their toy is out of reach, i.e. gaze at a hidden target or at the owner, gaze alternation between a hidden target and the owner, vocalisations and contacts. In this study, an additional variable was analysed: the position of the dog in relation to the location of the target. Dogs witnessed the hiding of a favourite toy, in a place where they could not get access to. We analysed how dogs engaged in communicative deictic behaviours in the presence of their owner; four heights of the target were tested. To control for the motivational effects of the toy on the dogs’ behaviour and for the referential nature of the behaviours, observations were staged where only the toy or only the owner was present, for one of the four heights. The results show that gazing at the container and gaze alternation were used as functionally referential and intentional communicative behaviours. Behavioural patterns of dog position, the new variable, fulfilled the operational criteria for functionally referential behaviour and a subset of operational criteria for intentional communication: the dogs used their own position as a local enhancement signal. Finally, our results suggest that the dogs gazed at their owner at optimal locations in the experimental area, with respect to the target height and their owner’s (or their own) line of gaze.

Abstract: A total of 17 microsatellite deoxyribonucleic acid loci used routinely for horse parentage control were used to evaluate genetic diversity among normal Arabian horses and severe combined immunodeficiency (SCID) carrier Arabian horses (ArS) and normal Arab-Barb horses and SCID carrier Arab-Barb horses (ArbeS). On the basis of the genotype of 186 horses, mean allelic diversity was estimated as 6.82, 5.53, and 6.7059 in normal Arabian horses, ArS, and for both groups of Arab-Barb horses, respectively. Five specific alleles were observed in ArS and ArbeS, with one common with ArS at HMS6, whereas five alleles common between ArS and ArbeS had a high frequency. Expected and observed heterozygosity showed great heterogeneity in the population studied and were similar or higher when compared with other studies on Arabian horses. Coefficient of gene differentiation Gst of Nei associated with Nei's genetic distance and multivariate correspondence analysis indicated a possible differentiation between the studied populations when analyzed separately according to breed. Probability of assignment of a horse to a specific group was assessed using a full and partial Bayesian approach. In all, 80.6% of Arab horses and 78.2% of Arab-Barb horses were assigned properly with a partial Bayesian test, which provided better results than the full one. These findings will be useful for identification of SCID carrier horses by using the microsatellite deoxyribonucleic acid loci used routinely for horse parentage control in our laboratory.

Abstract: Manoeuverability is a key requirement for successful terrestrial locomotion, especially on variable terrain, and is a deciding factor in predator–prey interaction. Compared with straight-line running, bend running requires additional leg force to generate centripetal acceleration. In humans, this results in a reduction in maximum speed during bend running and a published model assuming maximum limb force as a constraint accurately predicts how much a sprinter must slow down on a bend given his maximum straight-line speed. In contrast, greyhounds do not slow down or change stride parameters during bend running, which suggests that their limbs can apply the additional force for this manoeuvre. We collected horizontal speed and angular velocity of heading of horses while they turned in different scenarios during competitive polo and horse racing. The data were used to evaluate the limits of turning performance. During high-speed turns of large radius horizontal speed was lower on the bend, as would be predicted from a model assuming a limb force limit to running speed. During small radius turns the angular velocity of heading decreased with increasing speed in a manner consistent with the coefficient of friction of the hoof–surface interaction setting the limit to centripetal force to avoid slipping.