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Steinhoff, H. J., Lieutenant, K., & Redhardt, A. (1989). Conformational transition of aquomethemoglobin: intramolecular histidine E7 binding reaction to the heme iron in the temperature range between 220 K and 295 K as seen by EPR and temperature-jump measurements. Biochim Biophys Acta, 996(1-2), 49–56.
Abstract: Temperature-dependent EPR and temperature-jump measurements have been carried out, in order to examine the high-spin to low-spin transition of aquomethemogobin (pH 6.0). Relaxation rates and equilibrium constants could be determined as a function of temperature. As a reaction mechanism for the high-spin to low-spin transition, the binding of N epsilon of His E7 to the heme iron had been proposed; the same mechanism had been suggested for the ms-effect, found in temperature-jump experiments on aquomethemoglobin. A comparison of the thermodynamic quantities, deduced form the measurements in this paper, gives evidence that indeed the same reaction is investigated in both cases. Our results and most of the findings of earlier studies on the spin-state transitions of aquomethemoglobin, using susceptibility, optical, or EPR measurements, can be explained by the transition of methemoglobin with H2O as ligand (with high-spin state at all temperatures) and methemoglobin with ligand N epsilon of His E7 (with a low-spin ground state). Thermal fluctuations of large amplitude have to be postulated for the reaction to take place, so this reaction may be understood as a probe for the study of protein dynamics.
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Hunter, L., & Houpt, K. A. (1989). Bedding material preferences of ponies. J Anim Sci, 67(8), 1986–1991.
Abstract: The bedding preferences of ponies were determined using video recordings of nighttime (1900 to 0700) behavior of individually housed ponies. The ponies' behavior each minute was recorded to determine time budgets. In Exp. I, preference for bedding was determined using three mares, three stallions and two geldings given access to bedded and unbedded areas in a box stall. The ponies spent more time (66%) on the bedded area and were never observed lying on the unbedded areas. In Exp. II, three mares and six stallions were given access to a box stall, one side of which was bedded with wood shavings and the other with straw. Although some individual animals preferred one bedding over the other, neither form of bedding was preferred consistently. Time budgets in Exp. II were similar on both bedding materials. The ponies spent 12% of their nighttime lying, 2% walking, 35% eating and 50% standing inactively. Some ponies had a relatively strong preference for bedding, but the type of bedding preferred varied with the individual animal. Some individual ponies had no clear preference, but instead had a side or position preference
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Konstantinov, S. A., & Veselkin, A. G. (1989). [The intensity and efficiency of a gadfly attack on cattle depending on the number and location of the animals in the herd]. Parazitologiia, 23(1), 3–10.
Abstract: The effect of group was studied on cattle being attacked by horse flies of three genera. The method of simultaneous registrations of attacking horse flies in herds of 8 to 100 animals and on single cows was used. It has been shown that the effect of group reveals itself only when animals in the herd reach a certain minimum number, the effect rate depending on peculiarities of attacking of a given species of bloodsuckers, such as a part of responding individuals, distance of an attack, duration of contact with an object. These parameters tend to change with increasing number of animals in the herd. Therefore differences in the intensity of attacks on herds with different cattle stock cannot be explained proceeding only from differences in the occupied areas. The number of attacking horse flies decreases from the periphery of the herd to its centre and is not the same in different parts of the periphery. The effectiveness of attacking, ie the part of sucking individuals of a given species (genus) from the number of horse flies attacking for a definite period of time, is the highest in a large herd and increases in its ranges from the periphery to the centre. This dependence leads to a more even distribution of sucking individuals as compared to attacking ones.
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Rubenstein, D. I., & Hohmann, M. E. (1989). Parasites and Social Behavior of Island Feral Horses. Oikos, 3, 312–320.
Abstract: The horses of Shackelford Banks, North Carolina, USA, are heavily parasitized by intestinal worms and harassed by dipterans, and although both types influence behavior only internal parasites affect bodily condition and the structuring of horse society. Thirteen species of internal parasites were identified, but only 4 of 13 groups contain them all and even within groups differences among individuals are large. Among individuals ova emissions vary ranging from 50 to 76,875 eggs per gram. The most important environmental factors influencing egg production are season and a group's location on the island, presumably because of salinity and soil differences and their effects on ova survival. Of the social and life history factors, age, and group size, but neither reproductive state nor dominance status are important. The fitness consequences of internal parasitism may be large since the number emitted is negatively correlated with next year's bodily condition. Biting fly burdens are also affected by a variety of environmental factors. In general, horses are covered with more flies on sunny days, when winds are moderately brisk, when occupying dunes, and around mid-day. In contrast to endoparasites, fly burden is affected by reproductive condition and dominance status and tends to decrease as groups increase in size. Since groups do not grow very large, nor do females attempt to bring groups together, the negative effects of endoparasites appear to overide those associated with ectoparasites. Consequently, endoparasites appear to exert a stronger influence on social structure, even though ectoparasites seem to play a stronger role in shaping details of behavior.
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Kondo, S., Sekine, J., Okubo, M., & Asahida, Y. (1989). The effect of group size and space allowance on the agonistic and spacing behavior of cattle. Appl. Anim. Behav. Sci., 24(2), 127–135.
Abstract: The number of agonistic encounters in a group (frequency per h) and the mean distance to the nearest neighbor in a group (m) were analyzed by a multiple regression on the group size (number of animals in a group) and space allowance (m3 per animal) in each group of calves (6–13 months old, Holstein female and castrated male) and adult cattle (2–12 years old, Holstein heifers and cows or Holstein and Hereford grazing beef cattle). A total of 196 calves and 602 adult animals were used in this analysis. In calves, a significant correlation was found between agonistic behavior and space allowance (r=-0.48, P<0.01), but not between agonistic behavior and group sizes. The mean distance to the nearest neighbor in calf groups increased as the group size decreased and space allowance increased (R2=0.66, P<0.01). In adult cattle, the number of agonistic encounters increased linearly as the group size increased (r=+0.37, P<0.05). The relationship between agonistic behavior and 1(space allowance)2 was significant (r=+0.48, P<0.05). The mean distance to the nearest neighbor tended to increase as the group size decreased and the space allowance increased (R2=0.68, P<0.01). When the space allowance increased beyond 360 m2 per animal, the average distance to the nearest neighbor in the adult group was maintained within the range of 10–12 m.
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Huizinga, H. A., & van der Meij, G. J. W. (1989). Estimated parameters of performance in jumping and dressage competition of the Dutch Warmblood horse. Livestock Production Science, 21(4), 333–345.
Abstract: The objective of this study is to estimate several genetic parameters in the Dutch Warmblood riding horse population. The traits involved are performances in jumping and dressage competition. The following parameters are estimated: heritabilities for jumping and dressage; phenotypic and genetic correlations between jumping and dressage; and phenotypic and genetic correlations between performances at different ages. These parameters are estimated by restricted maximum likelihood (REML). Data are from 6899 horses with performances in jumping and 10 408 horses with performances in dressage competition. The horses are sired by 205 and 237 stallions for the two traits, respectively. The progeny range in age from 4 to 8 years old. The performance trait is a cumulatively derived score, that reflects the level of performance in competition. A square root transformation of the score is most appropriate to normalize the data. For estimation of phenotypic and genetic parameters the data is split into two data sets according to the age of the sires (offspring sired by older vs. younger stallions). For estimating correlations between performances at 4, 5 and 6 years of age, performances of the offspring out of previous years are linked to the data. The most unbiased estimates of heritability for jumping and dressage are from data derived from the youngest offspring sired by the younger stallions and are 0.20 and 0.10, respectively. Genetic correlation between jumping and dressage ranges from -0.27 to 0.10. The phenotypic correlation between these traits ranges from 0.15 to 0.26. Phenotypic and genetic correlations between performances at 4, 5 and 6 years average 0.95 and 0.75, respectively. These latter results have important implications for genetic evaluation of breeding candidates in the population.
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Kaplan, A. I., & Borodovskii, M. I. (1989). [Alternative animal behavior: a model and its statistical characteristics]. Nauchnye Doki Vyss Shkoly Biol Nauki, (3), 29–32.
Abstract: The rats' alternative behaviour in T-maze at simultaneous two-sided food refreshment in 13 trials a day during 6 days has been studied. It has been found that in the first testing days the indexes of alternative behaviour of animals correspond to the characteristics of the random alternation. However, on the 5-6th day of testing in the overwhelming majority of rats the true deviation of alternation index above or below than the theoretical values has been revealed. A question on the existence of two strategies of cognitive behaviour alteration and perseveration in rat population is under discussion.
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Stahlbaum, C. C., & Houpt, K. A. (1989). The role of the Flehmen response in the behavioral repertoire of the stallion. Physiol. Behav., 45(6), 1207–1214.
Abstract: The role of the Flehmen response in equine behavior was investigated under field and laboratory conditions. In Experiment 1, a field study made of five stallions on pasture with between three and eighteen mares each during the season indicated the following: 1) The Flehmen response was most frequently preceded by nasal, rather than oral, investigation of substances; 2) The stallions' rate of Flehmen varied with the estrous cycles of the mares; 3) The rate of Flehmen response did not show a variation with time of day; and 4) The Flehmen response was most frequently followed by marking behaviors rather than courtship behaviors. The results suggest that the Flehmen response is not an immediate component of sexual behavior, e.g., courtship of the stallion but may be involved in the overall monitoring of the mare's estrous cycle. Therefore the Flehmen response may contribute to the chemosensory priming of the stallion for reproduction. In Experiment 2 stallions were presented with urine or feces of mares in various stages of the reproductive cycle as well as with their own or other males' urine or feces. The occurrence of sniffing and Flehmen was used to determine the discriminatory ability of the stallions. Stallions can differentiate the sex of a horse on the basis of its feces alone, but cannot differentiate on the basis of urine. This ability may explain the function of fecal marking behavior of stallions.
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Lynch, J. J., Hinch, G. N., Bouissou, M. F., Elwin, R. L., Green, G. C., & Davies, H. I. (1989). Social organization in young Merino and Merino x Border Leicester ewes. Appl. Anim. Behav. Sci., 22(1), 49–63.
Abstract: The social behaviour of two groups of Merino ewes and one group of Merino x Border Leicester ewes was studied. Each group comprised eight sheep, 15 months of age and, within each group, the animals were of similar liveweight. Dominance rankings were established at each test, but there was little consistency in ewe rank over time. Similarly, little consistency was found in ewe ranking for movement order between pens, and for exploratory and fear test rankings. However, with tests on movement orders, some consistency in the sheep which ranked first was shown. In the field, no aggression was seen while sheep were grazing and there were no occasions when ranking related to movement could be observed. There were short-term associations between pairs of sheep, but these occurred in less than half the individuals. Although the spatial distribution was not studied, the lack of long-term association between pairs would suggest that strong spatial preference does not occur. It is concluded that the social organization of single-age Merino and Merino x Border Leicester ewes is not based on dominance or leadership ranking nor on long-term associations between individuals.
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Ellard, M. - E., & Crowell-Davis, S. L. (1989). Evaluating equine dominance in draft mares. Appl. Anim. Behav. Sci., 24(1), 55–75.
Abstract: The social hierarchy of a herd of 12 draft mares was assessed using agonism in the field, paired-feeding tests and a group-feeding test. Results from the paired-feeding test correlated significantly, but imperfectly, with those from the field. Differential motivation among subjects for the feed and disruption of ambiguous relationships among mares reduced the reliability of the paired-feeding test as a measure of social dominance. Results from the group-feeding test did not correlate significantly with the field hierarchy and only a few mares ever ate from the bucket. Height, weight and age each correlated significantly with rank; a mare's tendency to remain alone did not. Total aggressive scores during the paired-feeding test correlated with rank. However, a high-ranking mare was no more aggressive to each of her subordinates than was a low-ranking mare. Rather, all mares aggressed more against individuals close in rank to themselves and with preferred field associates. In the field, mares associated most with other mares of similar rank.
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