925 research outputs found
Phasespace Correlations of Antideuterons in Heavy Ion Collisions
In the framework of the relativistic quantum molecular dynamics approach
({\small RQMD}) we investigate antideuteron () observables in
Au+Au collisions at 10.7~AGeV. The impact parameter dependence of the formation
ratios and is calculated. In central
collisions, the antideuteron formation ratio is predicted to be two orders of
magnitude lower than the deuteron formation ratio. The yield in
central Au+Au collisions is one order of magnitude lower than in Si+Al
collisions. In semicentral collisions different configuration space
distributions of 's and 's lead to a large
``squeeze--out'' effect for antideuterons, which is not predicted for the
's
MANAGEMENT AND IMPLICATIONS OF A NEW PREDATOR SPECIES IN NORTH-EASTERN ITALY: THE GOLDEN JACKAL (CANIS AUREUS)
The golden jackal is a relatively new species in Italy, where it appeared about 30 years ago in the North-East. This study reports the first outcomes of acoustic monitoring of the species and the first warning of possible human-animal conflicts in Friuli-Venezia Giulia. We carried out 145 jackal-howling sessions in 5 macro-areas from summer 2011 to spring 2013, with an average of 5 emissions/session (679 emissions). We recorded 42 vocalizations, which were then analyzed in order to estimate the number of callers by screening the fundamental frequency of the single emissions within a howl. Jackal presence was confirmed only in 2 out of the 5 monitored macro-areas (Carnia and Carso), but it was stable only in Carso, with a 20% response rate. The response rate decreased with the number of emissions in a session (E1=9.6%, E2=7.1%, E3=8.0%, E4=3.2%, E5=2.5%, E6 and following=0.0%) and the responses were concentrated in February-April and July-August. Acoustic analysis of vocalizations allowed determining the number of emitters: one animal in 18 cases, two animals in 13 cases, three animals in 11 cases. These numbers are lower than those initially estimated during field recording sessions, when up to 5 individuals were supposed to vocalize simultaneously in one session. However, the presence of groups of up to 7 individuals has been recorded by scout cameras in Carso. In this area, three predation events, leading to the loss of 11 sheep, were reported by one farmer during the study period and are now becoming more frequent. In spite of this, the presence of a predator is well tolerated by this farmer, who valued this species as a touristic attraction for its importance as a source of biodiversity and landscape preservation. This situation suggests that, at the moment, the coexistence of the predator with farming activities may be possible, but a continuous monitoring of the species is required in order to prevent future problems. Jackal howling appeared to be an adequate technique for jackal monitoring. In order to optimize the efforts, our results suggest that sampling should be concentrated in few months, when response rate is higher, and limited to 3-4 emissions/session. Acoustic analysis of the recorded vocalizations is highly recommended in order to obtain more reliable information on the number of individuals. To this aim, keeping records of indirect signs of presence and the use of scout cameras may help to get a complete information on this expanding species
Impact of wolf (Canis lupus) on animal husbandry in an Apennine province
Predation has always been an important problem in extensive sheep farms, causing serious economic losses to the farmers. In the Province of Lucca, the presence of reproductive wolf packs has already been confirmed in natural reserves, but occasional signs of presence of the predator have been reported also in neighbouring areas. The present research has been carried out in this Province (between the Orecchiella Natural Reserve and the medium Serchio Valley), in order to obtain more complete information on the location of the wolf (with transects, wolf- howling and snow-tracking), and to verify the real impact and risk factors of predation on live- stock (by means of on-farm surveys carried out in 42 semi-extensive farms) in this area. The presence of wolf was confirmed in the study area with a minimum of four adult individuals and at least one pup: this pack lives around the peaks of the Apennines in the municipalities covered by this investigation. A growing conflict between the wolf and the sheep and goat farms was observed: since 2007 there have been 25 attacks and three farms can be considered subject to chronic predation. The major risk factors are high altitude, large flock size and lack of fences and of guardian dogs. An accurate knowledge of wolf presence and the identification of the farms mostly at risk can be useful for future planning of interventions aimed at prevention and support of farmers, in order to mitigate the conflict caused by predation
Sheep predation : characteristics and risk factors
Predation has always been an important problem in extensive sheep farms, causing serious economic losses to the farmers. Official predation reports have recently been decreasing in the District of Pisa, in spite of the presence of two wolf packs in the area. The aim of the present research was to obtain reliable information on the characteristics of predation and to estimate the effectiveness of existing prevention methods in sheep farms of the southern District of Pisa, in order to set up predictive models for an improved and more focused prevention plan and support interventions by public authorities. On-farm surveys were carried out in 73 semi-extensive sheep farms. Predation events were reported by 75.3% of the farmers. Wolves seemed to be responsible for most of those events, although their actual role could be confirmed only in 34% of cases. Most of the events occurred in spring and 85.1% of them were concentrated during night time. The average number of sheep killed during each attack was 7.05. In 22.3% of cases, the number of sheep killed was 65 10. Proximity to protected areas and the presence of thick vegetation cover significantly affected the probability of a farm being subjected to chronic predation. Farm size was significantly higher in those cases. No clear indication about the effectiveness of prevention methods could be obtained from our survey. The results of this investigation highlighted the impact of predation in the Southern District of Pisa and emphasized the need for finding technical and political solutions to this problem. Attention should be focused on large farms, with thick vegetation cover and located close to protected areas. Further investigations should be carried out in order to test the effectiveness of suitable prevention methods in these farms
How can we assess positive welfare in ruminants?
Until now, most research has focused on the development of indicators of negative welfare, and relatively few studies provide information on valid, reliable, and feasible indicators addressing positive aspects of animal welfare. However, a lack of suffering does not guarantee that animals are experiencing a positive welfare state. The aim of the present review is to identify promising valid and reliable animal-based indicators for the assessment of positive welfare that might be included in welfare assessment protocols for ruminants, and to discuss them in the light of the five domains model, highlighting possible gaps to be filled by future research. Based on the existing literature in the main databases, each indicator was evaluated in terms of its validity, reliability, and on-farm feasibility. Some valid indicators were identified, but a lot of the validity evidence is based on their absence when a negative situation is present; furthermore, only a few indicators are available in the domains of Nutrition and Health. Reliability has been seldom addressed. On-farm feasibility could be increased by developing specific sampling strategies and/or relying on the use of video- or automatic-recording devices. In conclusion, several indicators are potentially available (e.g., synchronisation of lying and feeding, coat or fleece condition, qualitative behaviour assessment), but further research is required
The Origin of Transverse Flow at the SPS
We study the transverse expansion in central Pb+Pb collisions at the CERN
SPS. Strong collective motion of hadrons can be created. This flow is mainly
due to meson baryon rescattering. It allows to study the angular distribution
of intermediate mass meson baryon interactions.Comment: submitted to Phys. Lett.
A stopped Delta-Matter Source in Heavy Ion Collisions at 10 GeV/n
We predict the formation of highly dense baryon-rich resonance matter in
Au+Au collisions at AGS energies. The final pion yields show observable signs
for resonance matter. The Delta(1232) resonance is predicted to be the dominant
source for pions of small transverse momenta. Rescattering effects --
consecutive excitation and deexcitation of Deltas -- lead to a long apparent
lifetime (> 10 fm/c) and rather large volumina (several 100 fm^3) of the
Delta-matter state. Heavier baryon resonances prove to be crucial for reaction
dynamics and particle production at AGS.Comment: 17 pages, 5 postscript figures, uses psfig.sty and revtex.st
How Can We Assess Positive Welfare in Ruminants?
Until now, most research has focused on the development of indicators of negative welfare, and relatively few studies provide information on valid, reliable, and feasible indicators addressing positive aspects of animal welfare. However, a lack of suffering does not guarantee that animals are experiencing a positive welfare state. The aim of the present review is to identify promising valid and reliable animal-based indicators for the assessment of positive welfare that might be included in welfare assessment protocols for ruminants, and to discuss them in the light of the five domains model, highlighting possible gaps to be filled by future research. Based on the existing literature in the main databases, each indicator was evaluated in terms of its validity, reliability, and on-farm feasibility. Some valid indicators were identified, but a lot of the validity evidence is based on their absence when a negative situation is present; furthermore, only a few indicators are available in the domains of Nutrition and Health. Reliability has been seldom addressed. On-farm feasibility could be increased by developing specific sampling strategies and/or relying on the use of video- or automatic-recording devices. In conclusion, several indicators are potentially available (e.g., synchronisation of lying and feeding, coat or fleece condition, qualitative behaviour assessment), but further research is required
Effect of the change of social environment on the behavior of a captive brown bear (Ursus arctos)
We observed the behavior of a captive sterilized male brown bear before and after the death of his female sibling to investigate the effect of the change of social environment on his behavior and welfare. Observations were carried out by continuous recording during daylight for 6 wk prior to hibernation when the bear was kept with the sibling, and they were repeated 2 years later when the bear was alone (total observation time is 108 h). Feeding, moving, and the total amount of time spent resting (including sleeping and alert inactive) were not affected by the change of social environment. However, when the bear was alone, the percentage of time he spent alert inactive almost trebled (pair, 17.7 \ub1 3.3%; alone, 48.5 \ub1 5.5%; P < 0.001), and the time spent sleeping was less than one-third (pair, 51.1 \ub1 6.1%; alone, 14.2 \ub1 5.0%; P < 0.001) than when the female was present. The bear spent most of his sleeping time in lateral lying posture (a posture probably associated with rapid eyes movement sleep). The percentage of time dedicated to this posture was significantly reduced after the death of his sibling (pair, 35.9 \ub1 7.4%; alone, 15.0 \ub1 5.4%; P < 0.05), whereas the percentage of time spent in quadrupedal posture increased (pair, 17.1 \ub1 5.4%; alone, 37.8 \ub1 7.8; P < 0.05). One of the possible reasons for these changes may be an increased risk perception of the bear after the death of his sibling. Our results highlight the importance of social environment and of its changes, which should be carefully considered to maintain captive bears in good welfare conditions
Evaluation of Maine Coon cat behavior during three different management situations
Today, cats are one of the most widespread and beloved companion animals: they share their life with people and are perceived as social partners by their owner. The knowledge and understanding of cat-human communication and of the behavior exhibited in response to different emotions is essential to improve the management of housed cats. The aim of this study was to analyze and compare the behavior of cats in three different situations that can occur in house cats' lives. Ten Maine Coon cats, four males and six females, ranging in age from one to 13 years, belonging to a single private owner and managed under the same conditions, were exposed randomly to three different contexts for five minutes (waiting for food, isolation in unknown environment, and brushing). All the situations were video-recorded and subsequently analyzed. The behaviors oriented to environment, oriented to food bowl, locomotion, active interactions, yawning, lip licking and swallowing, and salivation mainly characterized waiting for food, while isolation appears principally characterized by behaviors such as hiding, scratching, worried positions, and exploration. Withdrawal, passive interactions, aggressive behaviors, facial discomfort, and purring characterized brushing. Vocalizations were significantly more frequent during isolation and brushing than during waiting for food, but it is possible that the characteristics of the vocalizations in these two situations are different. Our principal finding is that cats showed different behavioral patterns in the three situations and, in particular, their behavior during brushing was very different than in the two other situations. It can be hypothesized that these different behavioral responses are due to the different emotional states elicited by each of the three challenging and potentially stressful situations. Further investigation is being carried out to better understand cats' behaviors and emotions to improve cats' management in the household
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