|
Records |
Links |
|
Author |
Wallner, B.; Brem, G.; Muller, M.; Achmann, R. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Fixed nucleotide differences on the Y chromosome indicate clear divergence between Equus przewalskii and Equus caballus |
Type |
Journal Article |
|
Year |
2003 |
Publication |
Animal Genetics |
Abbreviated Journal |
Anim Genet |
|
|
Volume |
34 |
Issue |
6 |
Pages |
453-456 |
|
|
Keywords |
Animals; Base Sequence; DNA, Mitochondrial/genetics; Genetic Variation/*genetics; Horses/classification/*genetics; Male; Molecular Sequence Data; Phylogeny; Probability; Species Specificity; Y Chromosome/*genetics |
|
|
Abstract |
The phylogenetic relationship between Equus przewalskii and E. caballus is often a matter of debate. Although these taxa have different chromosome numbers, they do not form monophyletic clades in a phylogenetic tree based on mtDNA sequences. Here we report sequence variation from five newly identified Y chromosome regions of the horse. Two fixed nucleotide differences on the Y chromosome clearly display Przewalski's horse and domestic horse as sister taxa. At both positions the Przewalski's horse haplotype shows the ancestral state, in common with the members of the zebra/ass lineage. We discuss the factors that may have led to the differences in mtDNA and Y-chromosomal observations. |
|
|
Address |
Institut fur Tierzucht und Genetik, Veterinarmedizinische Universitat Wien, Veterinarplatz, Wien, Austria. wallner@i122server.vu-wien.ac.at |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0268-9146 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
PMID:14687077 |
Approved |
no |
|
|
Call Number |
Equine Behaviour @ team @ |
Serial |
5038 |
|
Permanent link to this record |
|
|
|
|
Author |
Atwill, E.R.; Mohammed, H.O.; Lopez, J.W. |
|
|
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Evaluation of travel and use as a risk factor for seropositivity to Ehrlichia risticii in horses of New York state |
Type |
Journal Article |
|
Year |
1996 |
Publication |
American Journal of Veterinary Research |
Abbreviated Journal |
Am J Vet Res |
|
|
Volume |
57 |
Issue |
3 |
Pages |
272-277 |
|
|
Keywords |
Animals; Cross-Sectional Studies; Ehrlichiosis/epidemiology/*veterinary; Female; *Horse Diseases; Horses; Male; New York/epidemiology; Probability; Random Allocation; Risk Factors; *Travel |
|
|
Abstract |
OBJECTIVES--To determine whether mean annual frequency and destination of equine travel was associated with exposure to Ehrlichia risticii and whether these associations were modified by horses' place of residence. DESIGN--Cross-sectional study. SAMPLE POPULATION--511 equine operations containing 2,587 horses were visited in New York state from a target population of 39,000 operations. PROCEDURE--Each horse was tested for serum antibodies against E risticii, using indirect fluorescent antibody. Information on the horse's travel history, farm's management practices, and surrounding ecology was obtained by personal interview and resource maps. Statistical analyses were performed on 2 cohorts of animals: all horses enrolled in the study and horses born on the property or that resided at least 4 years on the farm. Three county-based risk regions (RR) were identified by use of cluster analysis. RESULTS--Mean seroprevalence for each of the 3 RR was 2.4 (low risk), 8.5 (moderate risk), and 18.5% (high risk) for cohort 1 and 2.5, 8.0, and 18.4% for cohort 2. Among cohorts 1 and 2, pleasure riding and breeding trips were associated with exposure to E risticii, but horse residence (low, moderate, or high RR) was an effect modifier for these associations. Among cohort 1 and stratifying the analysis according to the RR for the travel destination, trail riding at low RR and trail riding at high RR were associated with exposure. Among cohort 2 and stratifying the analysis according to the RR for the travel destination, breeding trips were associated with exposure, and strong effect modification was present for horse residence (low, moderate, or high RR). CONCLUSIONS--Only certain types of travel to specific RR were associated with higher risk of exposure to E risticii. In many instances, travel was not associated, or was associated, with a reduced risk of exposure. |
|
|
Address |
Department of Clinical Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853, USA |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0002-9645 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
PMID:8669754 |
Approved |
no |
|
|
Call Number |
Equine Behaviour @ team @ |
Serial |
2658 |
|
Permanent link to this record |
|
|
|
|
Author |
VanDierendonck, M.C. |
![find record details (via OpenURL) openurl](img/xref.gif)
|
|
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Diff erences in social behaviour between late pregnant, post-partum and barren mares in a herd of Icelandic horses |
Type |
Manuscript |
|
Year |
2006 |
Publication |
The Importance of Social Relationships in Horses |
Abbreviated Journal |
|
|
|
Volume |
Chapter 5 |
Issue |
|
Pages |
|
|
|
Keywords |
Feral horses are social animals, which have to rely on survival strategies centered on the formation of cohesive social bonds within their bands. Many problems in the husbandry of social animals such as horses, are due to the fact that the limits of their adaptive abilities are exceeded. Evidence suggests that the fundamental social characteristics of domestic horses have remained relatively unchanged. The social structure, social strategies and social interactions were investigated (3 non-consecutive years, 24 hr per day for several weeks) in long term established groups of domestic horses (mares and geldings of all ages) and a few small introduced groups, kept in (semi)natural environments. The general aim was to investigate the social needs of domestic horses. The social life of domestic horses was characterised by long lasting bonds with preferred partners which were established and maintained by allogrooming, play, proximity and dominance behaviours. Bonding partners were mainly found within the same sex-age group, but adult geldings also bonded with sub-adult mares and geldings. Adult mares were clustered in a group, while the other animals formed a second group. Among the adult mares, subgroups according to reproductive state were formed. Individuals regulated their social network by interfering with interactions between other members of the herd, which in itself is complex. An intervention is a behavioural action of one animal that actively interferes with an ongoing interaction between a dyad with the apparent aim of altering that interaction. This was verified by post-hoc analyses of disturbed and undisturbed interactions. Interventions in allogrooming or play were performed significantly more often when at least one member of the initial dyad was a preferred partner of, or familiar to (within the small introduced bands) the intervener. The stronger the preferred association in allogrooming between the intervener and member(s) of the initial dyad, the higher the probability the intervener would displace one initial member and continue allogrooming with the other. Just five behaviours were extracted which reliably reflected the dominance relations among horses. Aggression with the hind quarters was used both offensively and defensively and therefore not suitable as a reliable parameter. Individual dominance relationships were related to social experience. The implications of these findings for horse husbandry were assessed. It is argued that the execution of affiliative behaviours may be rewarding in itself, and therefore always will be a highly motivated behaviour. It is shown that social positive physical interactions (allogrooming, play) with other horses is an ethological need and therefore indispensable in modern husbandry systems. Ethological needs are so important for the animal that husbandry systems that lack the possibilities to execute such behaviours will cause chronic stress. It is concluded that all horses need physical social contact, and that horses, which lack appropriate social learning experiences during ontogeny, may be hampered in their social functioning later in life. Solutions for problems, including dominance problems, in individual social housing and group housing are presented. |
|
|
Abstract |
Feral horses are social animals, which have to rely on survival strategies centered on the formation of cohesive social bonds within their bands. Many problems in the husbandry of social animals such as horses, are due to the fact that the limits of their adaptive abilities are exceeded. Evidence suggests that the fundamental social characteristics of domestic horses have remained relatively unchanged. The social structure, social strategies and social interactions were investigated (3 non-consecutive years, 24 hr per day for several weeks) in long term established groups of domestic horses (mares and geldings of all ages) and a few small introduced groups, kept in (semi)natural environments. The general aim was to investigate the social needs of domestic horses. The social life of domestic horses was characterised by long lasting bonds with preferred partners which were established and maintained by allogrooming, play, proximity and dominance behaviours. Bonding partners were mainly found within the same sex-age group, but adult geldings also bonded with sub-adult mares and geldings. Adult mares were clustered in a group, while the other animals formed a second group. Among the adult mares, subgroups according to reproductive state were formed. Individuals regulated their social network by interfering with interactions between other members of the herd, which in itself is complex. An intervention is a behavioural action of one animal that actively interferes with an ongoing interaction between a dyad with the apparent aim of altering that interaction. This was verified by post-hoc analyses of disturbed and undisturbed interactions. Interventions in allogrooming or play were performed significantly more often when at least one member of the initial dyad was a preferred partner of, or familiar to (within the small introduced bands) the intervener. The stronger the preferred association in allogrooming between the intervener and member(s) of the initial dyad, the higher the probability the intervener would displace one initial member and continue allogrooming with the other. Just five behaviours were extracted which reliably reflected the dominance relations among horses. Aggression with the hind quarters was used both offensively and defensively and therefore not suitable as a reliable parameter. Individual dominance relationships were related to social experience. The implications of these findings for horse husbandry were assessed. It is argued that the execution of affiliative behaviours may be rewarding in itself, and therefore always will be a highly motivated behaviour. It is shown that social positive physical interactions (allogrooming, play) with other horses is an ethological need and therefore indispensable in modern husbandry systems. Ethological needs are so important for the animal that husbandry systems that lack the possibilities to execute such behaviours will cause chronic stress. It is concluded that all horses need physical social contact, and that horses, which lack appropriate social learning experiences during ontogeny, may be hampered in their social functioning later in life. Solutions for problems, including dominance problems, in individual social housing and group housing are presented. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
Ph.D. thesis |
|
|
Publisher |
|
Place of Publication |
Universiteit Utrecht |
Editor |
|
|
|
Language |
|
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
|
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
|
Approved |
no |
|
|
Call Number |
Equine Behaviour @ team @ |
Serial |
2370 |
|
Permanent link to this record |
|
|
|
|
Author |
Real, L.A. |
|
|
Title ![sorted by Title field, descending order (down)](img/sort_desc.gif) |
Animal choice behavior and the evolution of cognitive architecture |
Type |
Journal Article |
|
Year |
1991 |
Publication |
Science (New York, N.Y.) |
Abbreviated Journal |
Science |
|
|
Volume |
253 |
Issue |
5023 |
Pages |
980-986 |
|
|
Keywords |
Animals; Bees/genetics/*physiology; Biomechanics; *Choice Behavior; *Cognition; *Evolution; Mathematics; Models, Genetic; Probability |
|
|
Abstract |
Animals process sensory information according to specific computational rules and, subsequently, form representations of their environments that form the basis for decisions and choices. The specific computational rules used by organisms will often be evolutionarily adaptive by generating higher probabilities of survival, reproduction, and resource acquisition. Experiments with enclosed colonies of bumblebees constrained to foraging on artificial flowers suggest that the bumblebee's cognitive architecture is designed to efficiently exploit floral resources from spatially structured environments given limits on memory and the neuronal processing of information. A non-linear relationship between the biomechanics of nectar extraction and rates of net energetic gain by individual bees may account for sensitivities to both the arithmetic mean and variance in reward distributions in flowers. Heuristic rules that lead to efficient resource exploitation may also lead to subjective misperception of likelihoods. Subjective probability formation may then be viewed as a problem in pattern recognition subject to specific sampling schemes and memory constraints. |
|
|
Address |
Department of Biology, University of North Carolina, Chapel Hill 27599-3280 |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Summary Language |
|
Original Title |
|
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0036-8075 |
ISBN |
|
Medium |
|
|
|
Area |
|
Expedition |
|
Conference |
|
|
|
Notes |
PMID:1887231 |
Approved |
no |
|
|
Call Number |
Equine Behaviour @ team @ |
Serial |
2846 |
|
Permanent link to this record |