| Home | << 1 2 3 4 5 >> |
|
Hamilton, W. D. (1971). Geometry for the selfish herd. J. Theor. Biol., 31(2), 295–311.
Abstract: This paper presents an antithesis to the view that gregarious behaviour is evolved through benefits to the population or species. Following Galton (1871) and Williams (1964) gregarious behaviour is considered as a form of cover-seeking in which each animal tries to reduce its chance of being caught by a predator.
It is easy to see how pruning of marginal individuals can maintain centripetal instincts in already gregarious species; some evidence that marginal pruning actually occurs is summarized. Besides this, simply defined models are used to show that even in non-gregarious species selection is likely to favour individuals who stay close to others. Although not universal or unipotent, cover-seeking is a widespread and important element in animal aggregation, as the literature shows. Neglect of the idea has probably followed from a general disbelief that evolution can be dysgenic for a species. Nevertheless, selection theory provides no support for such disbelief in the case of species with outbreeding or unsubdivided populations. The model for two dimensions involves a complex problem in geometrical probability which has relevance also in metallurgy and communication science. Some empirical data on this, gathered from random number plots, is presented as of possible heuristic value. Keywords: Animals; Anura; *Behavior, Animal; Breeding; Communication; Evolution; Fear; Metallurgy; *Models, Biological; Probability; Snakes; *Spatial Behavior
|
|
Haring, H. (2005). Development, level and prospects of the german horse breeding. Zuechtungskunde, 77(6), 490–495.
Abstract: The economic impact of the horses of the Federal Republic of Germany has gone up, the statistic numerals verify obviously that Germany took pride of place in Europe in terms of numbers of riders as well as numbers of horses. Successes of German branded horses let their breeders reach the summit worldwide. The carefully agreed breeding programme connects practical cognitions with those of science and permits the leading breeding areas unobstructed space to set their own priorities. Globalisation and rised demand of customers forces breeding associations towards a far-reaching reorganisation because just large powerful institutions can meet these requirements. An end of this process, which scarcely has just begun, cannot yet be conceivable seen. – Eugen Ulmer KG, Stuttgart.
|
|
Hori, Y., Takimoto, A., & Fujita, K. (2012). Are there breed difference in referential behavior in horses (Equus caballus)? In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Domesticated animals are characterized by variability of breeds. There is a great diversity in body size and/or coat color between different breeds. However, there are few scientific researches about difference in cognition and behavior between breeds. Comparison of behavior between breeds may be useful for the study of genetics behind the diversity of cognition and behavior. In the present study, we investigated behavioral differences between horse breeds. We tested two different breeds which have different histories, thoroughbreds and creoles. Thoroughbreds are racing horses which have been exposed to strict selection toward racing performance for about 300 years. Creoles are descendents of horses which were brought to South America by Spanish people in 15th century and used by native cowboys for riding. We compared the behavior in a difficult situation by using an “unsolvable task”. The experimenter put a food reward into a transparent box and closed it firmly so that horses could not take the reward. We compared the referential behavior (gazing behavior toward the experimenter) between thoroughbreds and creoles. We analyzed referential behavior by using generalized linear models (GLM) and model selection by Akaike’s information criterion (AIC). There were no effect of breed in the frequency and the duration of the referential behavior. But the latency before looking at the experimenter tended to be shorter in thoroughbreds than in creoles. This result suggests that there may be breed differences in horses’ social cognition and behavior. However, the effect of sex was also seen. Furthermore, we could not exclude the environmental effect (e. g. feeding environments, trainings) in this study. So we cannot explain the variation in referential behavior by breed effect only. We need to replicate the result by controlling environmental effects.
|
|
Vidament, M., Yvon. J.-M., Roche, H., Le Bon, H., Menard, C., Delfosse, A., et al. (2012). Temperament of stallions: relation with age, breed and level of riders. In K. Krueger (Ed.), Proceedings of the 2. International Equine Science Meeting (Vol. in press). Wald: Xenophon Publishing.
Abstract: Temperament is an important factor when working with horses. Behavioral tests have been developed to measure certain dimensions in horses. Relations between temperament and ability to riding activity have been highlighted (Lansade 2008a). The aims of this study were 1) to evaluate the effect of age on temperament, 2) to verify that temperament are related to breeds 3) to check if the ease to be ridden is in relation with temperament, on a first set of data. Five dimensions of temperament have been measured in 98 field stallions (Table 1). They were tested as described by Lansade (2008 a,b): fearfulness/curiosity (tests: crossing a novel aera, suddenly opening an umbrella, novel object), gregariousness (test: isolation), locomotor activity (during the other tests), reactivity/curiosity to a non familiar human (tests: passive and active human), tactile (Von Frey filament) and auditory sensitivities. Table 1: Number of stallions according to breed (or group of breeds) and age. Breeds or groups of breeds Young (<13 years) Old (>=13 <20 years) Merens 1 15 10 Leasure horse breeds 2 13 10 Jumping pony breeds 3 / 20 Jumping horse breeds4 9 10 Arabians / 11 Total 37 61 (1) Merens : french mountain horse breed (2) Appaloosa, Barbe, Lusitanian, Polish, Paint (3) French Saddle Pony, Connemara, New Forest, Welsh (4) French Saddle Horse, Anglo-Arab, KWPN, Foreign breeds Effect of age. Due to imbalanced data, only stallions from 3 breed groups were compared (29 young ones selected at random and 30 old ones). Young stallions presented a higher emotivity (more elevated distance/intensity of the flight after umbrella opening (P=0.001)) and curiosity (more sniffings/nibblings the passive human (P=0.04) and the novel object (P<0.0001)) compared to old ones. Relation with breed groups. In young stallions, differences were noted : in the number of trots during social isolation (P=0.001) and in the tactile sensitivity (P=0.005). Merens had smaller values than Jumping horses for these 2 variables. In older stallions, differences were also noted: in the number of sniffings/nibblings the novel object (P=0.04), in the manner to cross the novel aera (P=0.03), in the distance and intensity of the flight after umbrella opening (P=0.04), in the number of trots during isolation (P=0.02) and in the tactile sensitivity (P=0.03). Merens had lower reactivity compared: 1) to Arabians (for novel aera) and 2) compared to Jumping ponies and Jumping horses (for isolation and tactile sensitivity). Minimal level of rider. Stallions of all ages and breeds were divided into 3 groups according to the level of riders able to ride them safely, according to a questionnaire: beginners, intermediate level and pre-national competition level. Stallions adapted to beginners showed lower values in the number of trots during isolation (P=0.02) and in the tactile sensitivity (P=0.03) than stallions rode by pre-competition level riders. Conclusion : The intensity of fear reactions to suddenness decreased with age. Differences between breeds and eases of use have been related to temperament measurements.
Keywords: temperament, age, breed, fear, gregarity
|
|
Clutton-Brock, T. H., Russell, A. F., Sharpe, L. L., Brotherton, P. N., McIlrath, G. M., White, S., et al. (2001). Effects of helpers on juvenile development and survival in meerkats. Science, 293(5539), 2446–2449.
Abstract: Although breeding success is known to increase with group size in several cooperative mammals, the mechanisms underlying these relationships are uncertain. We show that in wild groups of cooperative meerkats, Suricata suricatta, reductions in the ratio of helpers to pups depress the daily weight gain and growth of pups and the daily weight gain of helpers. Increases in the daily weight gain of pups are associated with heavier weights at independence and at 1 year of age, as well as with improved foraging success as juveniles and higher survival rates through the first year of life. These results suggest that the effects of helpers on the fitness of pups extend beyond weaning and that helpers may gain direct as well as indirect benefits by feeding pups.
|
|
Momozawa, Y., Takeuchi, Y., Tozaki, T., Kikusui, T., Hasegawa, T., Raudsepp, T., et al. (2007). SNP detection and radiation hybrid mapping in horses of nine candidate genes for temperament. Anim Genet, 38(1), 81–83.
|
|
Nocera, J. J., Forbes, G. J., & Giraldeau, L. - A. (2006). Inadvertent social information in breeding site selection of natal dispersing birds. Proc Biol Sci, 273(1584), 349–355.
Abstract: Several species use the number of young produced as public information (PI) to assess breeding site quality. PI is inaccessible for synchronously breeding birds because nests are empty by the time the young can collect this information. We investigate if location cues are the next best source of inadvertent social information (ISI) used by young prospectors during breeding site choice. We experimentally deployed ISI as decoys and song playbacks of breeding males in suitable and sub-optimal habitats during pre- and post-breeding periods, and monitored territory establishment during the subsequent breeding season for a social, bobolink (Dolichonyx oryzivorus), and a more solitary species, Nelson's sharp-tailed sparrow (Ammodramus nelsoni). The sparrows did not respond to treatments, but bobolinks responded strongly to post-breeding location cues, irrespective of habitat quality. The following year, 17/20 sub-optimal plots to which bobolink males were recruited were defended for at least two weeks, indicating that song heard the previous year could exert a “carry-over attraction” effect on conspecifics the following year. Sixteen recruited males were natal dispersers, as expected when animals have little opportunity to directly sample their natal habitat quality. We suggest that differences in breeding synchronicity may induce an equivalent clinal distribution of ISI use.
|
|
Albentosa, M. J., Kjaer, J. B., & Nicol, C. J. (2003). Strain and age differences in behaviour, fear response and pecking tendency in laying hens. Br Poult Sci, 44(3), 333–344.
Abstract: 1. Behaviours associated with a high or low tendency to feather peck could be used as predictors of feather pecking behaviour in selective breeding programmes. This study investigated how strain and age at testing influenced responses in behavioural tests. 2. Four layer-type strains (ISA Brown, Columbian Blacktail, Ixworth and a high feather pecking (HP) and a low feather pecking (LP) line of White Leghorn) were reared in 6 same-strain/line pens of 8 birds from one day old. Birds in half the pens were given an open field test, a novel object test and a test with loose feather bundles between 4 and 12 weeks of age and a tonic immobility (TI) test at 13 weeks of age. All pens were tested with fixed feather bundles at 26 weeks, and undisturbed behaviour in the home pens was videoed at 1 and 27 weeks of age. Daily records of plumage damage were used as an indicator of feather pecking activity in the home pens. 3. Strain did not influence novel object test, open field test or loose feather test behaviour, although age effects in all three tests indicated a reduction in fearfulness and/or an increase in exploratory behaviour with increasing age. 4. White Leghorns showed longer TI durations than the other strains but less pecking at fixed feather bundles than ISA Browns and Columbian Blacktails. 5. There were few associations between behaviour in the 5 different tests, indicating that birds did not have overall behavioural traits that were consistent across different contexts. This suggests hens cannot easily be categorised into different behavioural 'types', based on their test responses and casts doubt on the usefulness of tests as predictors of feather pecking.
|
|
Collery, L. (1974). Observations of equine animals under farm and feral conditions. Equine Vet J, 6(4), 170–173.
|
|
Ionita, J. C., Poncet, P. A., Doherr, M. G., & Steiger, A. (2006). [Evaluation of the quality of husbandry of Franches-Montagnes horses in their breeding farms]. Schweiz Arch Tierheilkd, 148(4), 191–197.
Abstract: The quality of husbandry of Franches-Montagnes horses (FM) in Switzerland is evaluated on the basis of an investigation carried out in 2002 by the Swiss FM breeding federation. Questionnaires were sent to 3500 of its members and the results include data from 968 breeding enterprises, housing a total of 3965 FM: 46.1% were breeding mares (61.0% with foal at foot), 26.5% young stock, 1.3% stallions and 26.0% non breeding stock (74.6% of which were pleasure horses and 25.4% working horses). 57.6% of the FM were housed in individual boxes with or without permanent outdoor access, 25.4% were hold in groups with or without permanent outdoor access, the remaining 17.0% were kept in standing stalls. 95.0% of the FM had at least visual contact with other equines and 99.2% had sufficient light in their stable. 88.1% were stabled on long stalk straw, while only 4.3% were bedded on other materials other than straw. The average time spent at pasture per horse and per week ranged from 96.5 +/- 51.6 hours in summer to 27.2 +/- 26.7 hours in winter. On average, a FM is used for 8.3 +/- 6.5 hours per week. Horses with an paddock at their disposal spend an average of 39.8 +/- 45.9 hours there per week.
|