bluuebunny/crossref_metadata_2025_split huggingface dataset:
Infant monkey heart rate: Habituation and effects of social substitutes
Authors: Candland Douglas K. , Mason William A. 
Published: January 2005

AbstractThe heart rates of four infant monkeys that habitually clung to terry‐cloth towels were measured by frequency modulation (FM) telemetry while the animals were (1) alone in an unfamiliar room, (2) in a second unfamiliar room with a towel available, and (3) in the second room without a towel. The absence of the towel in the room in which it was sometimes available produced the highest heart rate and the presence of the towel produced the lowest heart rate. Under all conditions, heart rate decreased within sessions and over repeated exposures.
Effect of early outdoor experience on the activity of wild and semi‐domestic deermice
Authors: Price Edward O. 
Published: January 2005

AbstractThe gross activity of wild and semi‐domestic strains of prairie deermice was measured in two kinds of novel test apparatus (tilt‐cage and activity wheel). Differences in strain activity were not obtained in either apparatus. Activity was significantly decreased in both strains by early experience in the field and by rearing wild genotype subjects in large laboratory cages. It was suggested that differential early sensory experience associated with both qualitative and quantitative aspects of the early rearing environment may be responsible for the treatment effect. Whereas no daily changes in activity were noted in the tilt‐cages, activity in the wheels was sipnificantly higher on day 1 for all groups. In contrast to recent literature, wheel running activity did not change with total water deprivation.
Exploratory behavior in the dog: Experiential or age dependent?
Authors: Fox M. W. , Spencer J. W. 
Published: January 2005

AbstractTwo independent groups of dogs (41 cross‐sectional and 16 longitudinal) were tested either once or successively in a behavior arena at 5, 8, 12, or 16 weeks of age for exploration to novel stimuli. The stimulus situations were, respectively, an empty cage, rat in a cage, mirror, auditory click, toy puppy, and flashing light. In the cross‐sectional group at the early ages more time was spent with the rat‐in‐cage and flashing‐light stimuli than with others. No differences in exploration time to any stimuli were seen after 8 weeks. Both number of squares traversed and number of „yelps”︁ seemed to fluctuate more with increasing age. In contrast, the longitudinal group showed an increase in exploration with re‐testing. More time was spent with the toy pup and flashing light at the early ages, whereas the mirror was interacted with more at 12 and 16 weeks. Activity increased upon re‐testing, whereas vocalization decreased significantly after the first exposure to the testing arena. An evaluation of the reaction of each pup to a human was done on the day prior to testing. Those dogs that interacted with a human were also more exploratory and less fearful of a novel environment than those not interacting with a human. Results are discussed in terms of experiential rather than maturational factors as enhancing or modifying exploratory behavior in the dog.
Cerebellar control of the red nucleus and adjacent structures in the young rabbit
Authors: Laget P. , Delhaye‐Bouchaud N. 
Published: January 2005

AbstractMaturation of the cerebellar influence on rubral cells was studied in70 young rabbits aged from 3 to 17 days. Extracellular spike potentials of 187 neurons belonging to the magnocellular part of the red nucleus were recorded with glass microelectrodes. The differences observed between young and old animals are quantitative and particularly striking. Out of 107 cells in animals less than 8 days old, only 7 were facilitated or inhibited by cerebellar stimulation, whereas in older animals, out of 80 cells, 76 were facilitated or inhibited. Similar results were obtained for 273 perirubral cells and 72 oculomotor cells.The present results suggest that cerebello‐interposital or interposito‐rubral connections are not yet functional during the first postnatal week.
Distribution of adenosine triphosphatase activity in the developing brain of the chick embryo
Authors: Šťastný Františsek , Fröhlich Jiří , Chmelík Václav 
Published: January 2005

AbstractThe development and distribution of +‐K+‐stimulated and Mg2+‐dependent ATPase activity in different parts of the chick embryo brain were investigated. Maximal changes in the Na+‐K+‐stimulated ATPase activity in the hemispheres and optic lobes took place between day 15 and 17 and in the cerebellum and brain stem between day 17 and 19 of incubation. Most of this activity was localized in the membranous fraction of the chick embryo brain. An attempt was made to correlate the rapid rise in the activity of this enzyme with the development of electrical properties of the chick embryo brain.
Functional development of optic afferent system in chick embryos
Authors: Sedláčkek Jindřich 
Published: January 2005

AbstractA description is given of evoked activity in the optic lobes of chick embryos to different types of peripheral stimulation. During prehatching development (day 18–21 of incubation) the functional lability of optic neurons increases, as tested with repetitive stimulation (1–10 cps) and with paired flash stimuli. Maturation of the “OFF”‐evoked response proceeds in the same developmental period. This development is characterized by a decrease in the duration of light exposure necessary to produce the “OFF”‐response, by an increase in the amplitude of this type of evoked response, and by a decrease in latency, which becomes shorter than the latency of the “ON”‐response. The development of color differentiation (in the range of 486–687 mμ) has been studied according to the parameters of tectal evoked response (latency, amplitude, duration, steepness of crescent and decrescent part of negative spike). On day 19, there is evidence for differentiation of only 27 signs of the evoked response, particularly for blue and red color. The number of differential signs increases up to 40, until hatching (i.e.,) for blue, red, and orange colors.
Open‐field behavior in rats exposed prenatally to a low intensity‐low frequency, rotating magnetic field
Authors: Persinger Michael A. 
Published: January 2005

AbstractTwo experiments were conducted to study the behavioral effects of prenatal exposure to a low intensity, ultra‐low‐frequency magnetic field. In Experiment I, 117 albino rats that had been exposed continuously during their prenatal development to a 3 to 30 gauss, 0.5 Hz rotating magnetic field (RMF), and 83 control rats that had been exposed renatally to control conditions, were tested in an open field at 21 to 25 days of age. RMF‐exposed animals traversed significantly fewer squares than their controls in the open field (p < .001), but defecated significantly more in that situation (p < .001). RMF‐exposed males also traversed significantly fewer squares than the RMF‐exposed females (p < .05). Three RMF‐exposed litters that were nursed by control mothers did not differ significantly in open‐field activity from the pups in the 4 RMF‐exposed litters from which they were taken at birth. In Experiment 2, in which the experimenters did not know whether the subject was a RMF‐exposed rat or a control rat, 19 RMF‐exposed rats again traversed significantly fewer squares than the 20 control rats (p < .01).
Motor skills of infant rhesus monkeys with thalidomide‐induced forelimb malformations
Authors: Lindburg D. G. 
Published: January 2005

AbstractThe motor skills of 2 infant rhesus monkeys with thalidomide‐induced forelimb malformations were compared with those of normal infants of similar age and sex over an 8‐month period. In general, the experimental animals engaged in locomotor and manipulatory activities at about the same frequency as the normal subjects, but did so by development of compensatory response patterns. For instance, feet and mouth were used for activities that the normal animal performs manually.
Effects of chronic postnatal drug administration on adult dominance behavior in two genera of mice
Authors: Wolf Harold H. , Rowland Clayton R. 
Published: January 2005

AbstractThe experiments described examine the influence of early chronic treatment with amphetamine (AMPH) or chlorpromazine (CPZ) on the formation of adult dominance behavior in two genera of mice, i.e., Peromyscus maniculatus bairdi and a random bred, Swiss albino strain of Mus musculus. It was found that AMPH‐pretreated Swiss albinos were significantly more dominant than either CPZ‐pretreated or control animals. Early drug treatment had little effect on dominance behavior of adult bairdi. These results indicate that chronic administration of certain drugs to young animals is capable of producing a quantitative change in the formation of adult behavioral patterns. Moreover, the degree to which early drug treatment alters adult behavior is influenced by the genetic background of the organism.
Motor response thresholds to electrical stimulation at the wrist in human newborns
Authors: Ellingson Robert J. , Ellis Ron R. 
Published: January 2005

AbstractTwo studies of motor response thresholds (RTs) to electricalstimulation at the wrist in newborns were done. Adult controls were employed. Strength‐duration curves for infant and adult RTs and adult sensory thresholds (STs) were plotted. RTs of infants are approximately 1.75 times higher than those for adults. Adult RTs are consistently 3 to 4 times higher than STs. Test‐retest reliabilities were satisfactory. RTs of half of the newborns were notably variable. No relationship between RT variability and stages of the neonatal wakefulness‐sleep cycle could be established, but RTs were significantly, although not markedly, higher during rapid‐eye‐movement (REM) episodes than during nREM. For evoked potential studies with newborns it has been decided to use as a stimulus a constant‐current square‐wave electrical pulse of 0.5 msec duration at RT during nREM sleep.
Orienting response of kittens with maturation defects
Authors: Berkson Gershon , Brown Thomas S. 
Published: January 2005

AbstractThe orienting response of hand and mother‐reared kittens who had been given daily doses of propylthiouracil during the first 50 days of life was tested at 60 days of age. Heart rate, respiration rate, and eye fixation on a visual stimulus were the measures used. A momentary light‐buzzer combination and a 30‐sec presentation of a rotating disc were the stimuli. There were no rearing or drug effects. Heart rate response was greater to the offset of the 30‐sec stimulus than to its onset. Respiration, the most sensitive measure, was speeded in the presence of a stimulus. Eye fixation, heart rate, and respiration rate curves during the 30‐sec stimulus were not parallel.
Effects of male odor during infancy on the maturation, behavior, and reproduction of female mice
Authors: Kennedy James M. , Brown Kenneth 
Published: January 2005

AbstractInfant female mice who were exposed to the odor of adult male mice of the same strain in the presence or absence of the mother were compared with mice who were not exposed with respect to maturation, open‐field behavior, and reproductive success. Exposure lasted 4 hr daily during days 4–18 post‐partum. No significant differences were found between the groups in their rates of growth or the age of ear, eye, and vaginal opening. However, the exposed groups displayed first estrus significantly earlier than non‐exposed groups: the group exposed in the presence of the mothers showing the earliest first estrus of all 4 groups.
Care of young under communal conditions in the mouse (MUS MUSCULUS)
Authors: Gandelman Ronald , Paschke Richard E. , Zarrow M. X. , Denenberg Victor H. 
Published: January 2005

AbstractLactating mice and their young were housed with either virgin female or male mice. Virgin females cared for the young as much as did the lactating animals and in one instance were actually seen to aid in their delivery. Males displayed little caretaking behavior in the communal situation but exhibited a full range of such behavior when housed individually with young.
Effects of thyroxine level and temperature manipulations upon the hatching of chick embryos (gallus domesticus)
Authors: Balaban Martin , Hill Joanna 
Published: January 2005

AbstractThyroxine levels within chick embryos (Gallus domesticus) and incubation temperature were manipulated late in development in order to determine those events most proximal to the time of hatching that are both necessary and sufficient for the appearance of the hatched state. Events recorded include the time of breathing initiation, changes in breathing rate, time of puncture of the chorioallantoic membrane and changes in rate of loss of yolk sac material. It was found that a certain level of thyroxine is necessary for an animal to hatch, that breathing and puncture of the chorioallantoic membrane are necessary but not sufficient to predict the occurrence of hatching, and that a change in rate of loss of yolk sac material during the last 18 hr prior to hatching is sufficient to predict the occurrence of hatching. The explanatory hypothesis offered is that the endogenous increase in thyroxine levels acting via increased metabolic rates is necessary and sufficient for the animals to hatch.
Overview and critique of stages and periods in canine development
Authors: Fox M. W. 
Published: January 2005

AbstractSeveral aspects of CNS and behavioral developnient in relation to stages of development and the critical period of socialization in the dog are reviewed. Environmental and experiential treatments which may modify ontogeny are discussed. With particular emphasis on the specific and nonspecific effects of such treatment on the developing phenotype and the dependence or independence of a particular behavior or system upon stimulation, with or without which it may or may not develop. A more complete understanding of the evolutionary and developmental processes underlying the integrative development of the brain and behavior in different species is needed.
Visual and tactual variation seeking in the rat: Intermodal effects of early rearing
Authors: Gorry Thomas H. , Chibucos Thomas R. , Bell Robert W. 
Published: January 2005

AbstractConditions of variation and constancy for both tactual and visual stimulation were arranged in a 2 × 2 factorial. Hooded rats were reared under these conditions from 23 to 39 days of age, following which they lived in standard laboratory cages until 49 days of age. Preference tests for variation vs. constancy in both tactual and visual preference tests were conducted at 48 and 49 days of age. Ss previously exposed to the variable stimulation conditions, either tactual and/or visual, showed equal preference for variable stimulation in both tests. This was in contrast to the controls, which preferred the less variable stimulation in both tests. The intermodal effects of the early environmental stimulation were discussed in terms of Fiske and Maddi's activation model.
The effects of maternal nicotine absorption or hypoxic episodes upon appetitive behavior of rat offspring
Authors: Martin Joan C. , Becker R. F. 
Published: January 2005

AbstractOffspring of rats which had received either daily nicotine injections or hypoxic episodes throughout gestation were tested at adulthood on various appetitive schedules in a double‐bar Foringer chamber. The hypoxic offspring and the offspring whose mothers had received nicotine throughout gestation and the nursing period performed more poorly on fixed‐ratio, variable interval discrimination, and discrimination reversal schedules. Possible explanatory hypotheses are discussed.
Cardiorespiratory regulation and activity patterns of rat pups studied with their mothers during the nursing cycle
Authors: Hofer Myron A. , Grabie Morris 
Published: January 2005

AbstractRat pups aged 10 to 19 days were implanted with chronic electrodes and recorded while freely moving in the litter situation, during nursing and throughout naturally occurring maternal absences. Heart rates were significantly higher in the mother's presence (p<.01) while respiratory rates and percent of time spent active were identical under the 2 conditions. Pups' inactive heart rates progressively increased during the 20 min of nursing, while no such time trends were evident in other measures. Inactive heart rates decreased significantly (p<.01) as a function of age; respiratory rates and activity during nursing showed similar trends. A histogram of number of periods of activity bursts of different durations while pups were nursing showed a preponderance of 1‐ to 5‐sec bursts which were observed to be associated with active sucking and pawing movements. This pattern of short bursts of spontaneous activity was repeated almost identically when the mother was absent, although the behavior was qualitatively different. In a second experiment, increases in pups' body temperature of .2°C to 1.0°C were found to accompany active nursing. If such increases were imposed by an artificial heat source, heart rates of pups actually fell slightly. In a third study, heart rates were recorded from nursing mothers and found to be relatively unaffected by stimulation from the pups.
Color preferences and early perceptual discrimination learning in domestic chicks
Authors: Kovach Joseph K. , Hickox John E. 
Published: January 2005

AbstractThe speed of learning to discriminate between the colors blue and green was studied in dark‐raised chicks and in chicks having controlled exposure to these colors and white prior to learning. The data indicate that: (1) under all conditions of prior experience learning was faster when the response to blue was reinforced; (2) learning was significantly slower in dark‐raised groups than in groups having prior visual experience; and (3) learning was negatively related to systematic increase in the intensity of prior exposure stimulus. These data show that unlearned preferences play a significant role in learning; they combine additively with effects of experience prior to learning and reinforcement during learning.
Ontogeny of vision in the peking duck (Aanas platyrhynchos): The pupillary light reflex as a means for investigating visual onset and development in avian embryos
Authors: Heaton Marieta B. 
Published: January 2005

AbstractThe pupillary light reflex was used to determine the onset of visual function in Peking duck embryos (Anas platyrhynchos). Neurally mediated pupillary responses were first elicited on Day 18 (67% of total incubation), but 2 days prior to this and for several days during prenatal life, autonomous iris constriction was found. The neural and nonneural components of the response were separated using both an excision and a curare technique, each of which produced similar results. The pupillary technique for studying visual onset and development was further evaluated by a study of chick embryos (Gallus gallus), in which it was seen that results from this technique were in good agreement with those gleaned from more complex methods. It was concluded that the technique affords several advantages, particularly with respect to clarity of interpretation, ease of execution, and amount of information provided.
Aging and water submersion in C57BL/6J mice: Initial performance and retest as a function of recovery and water temperature
Authors: Wright William E. , Werboff Jack , Haggett Burton N. 
Published: January 2005

AbstractA total of 300 C57BL/6J male mice of 5 age groups (350, 470, 615, 720, or 845 ± 30 days of age) ranging from 50 to 120% of their expected life span were tested in a water submersion task with water temperature maintained at 23.5°C. Mice were retested to evaluate recovery from this stressor at either 24 or 168 hr after initial test. The retest was conducted at 1 of 3 temperatures (12.5, 23.5, or 34.5°C). On the initial water submersion test at 23.5°C, significant effects of advanced age were evident, with the oldest group (845 days) having the shortest time to submersion. No significant difference was evident between the two younger age groups with the longest time to submersion found in the middle (615‐day old) group. In the 2 oldest groups, submersion time scores decreased progressively and significantly. On the retest, significant effects were found for water temperature. The effects of water temperature were linear and consistent across ages and conditions with increasing temperature up to the maximum used in this experiment, resulting in longer time to submersion. The longer recovery time (168 hr.) to retest yielded inconsistent results with longer time to submersion scores found only in the 350 and 720‐day old groups.
Early maternal handling and preschool behavior of human children
Authors: Harper Lawrence V. 
Published: January 2005

AbstractRelease of adrenal medullary hormones as a result of activating the orthostatic pressor reflex may influence human infants' later behavior. The amount of time mothers held their infants in an upright position during the 1st and 3rd months postpartum was negatively related to the same children's tendency to cope with difficulties encountered in manipulating inanimate objects at the age of 30 months. This effect may represent a physiological response to early maternal handling.
The transition from filial to reproductive function of “Coitus‐Related” responses in young guinea pigs
Authors: Harper Lawrence V. 
Published: January 2005

AbstractA lordosis‐like response and a purring vocalization which was similar to that emitted by the adult male in precopulatory displays were observed in suckling guinea pigs. During that period in which parental stimulation was required to elicit micturition, both responses occurred in the context of nursing behavior and were frequently followed by the mother's licking the pups' anogenital regions; there was no sex difference in the display of these behaviors. When adult micturition behavior matured, the frequency of lordosing waned in both sexes; purring also declined in females, but in males, purring became associated with a hip‐swaying movement and increased in frequency. In adult females, the display of lordosis and/or purring was confined to estrous periods; males were not observed to lordose as adults, but purred when exposed to estrous females. Isolation‐ and mother‐reared animals displayed the same response organizations in infancy and adulthood. The functional reorganization of these responses in ontogeny is discussed.
Differences in maternal responsiveness between lactating and sensitized rats
Authors: Bridges Robert , Zarrow M. X. , Gandelman Ronald , Denenberg Victor H. 
Published: January 2005

AbstractRetrieval in lactating females, sensitized virgin females, and sensitized adult male rats was compared in a T‐maze extension of the home cage. The percent of lactating females that retrieved was significantly greater than in either the sensitized virgin of sensitized male groups. No difference was found between the two sensitized groups. The data are discussed in terms of the hormonal involvement in maternal behavior.
Vulnerability of developing brain: IV. Passive avoidance behavior in young rats following maternal undernutrition
Authors: Smart J. L. , Dobbing John 
Published: January 2005

AbstractAn investigation was carried out of the effect of undernourishing rats during much of gestation and throughout the whole suckling period on their behavior in a passive avoidance situation. All young were fed ad libitum from 21 days of age. Passive avoidance tests were done at 30 and 31 days in a two‐compartment box. On the first test normal rats tended to cross between compartments more promptly than previously underfed rats. Cross‐over latency was always greater on the second test than on the first. There were no significant differences in test 2 latency or in the ratio, test 2 latency/test 1 latency, between sexes, between normal and previously undernourished rats, between groups with 2‐min and 24‐hr interest intervals, or between master and yoked control rats. The last finding indicates that the apparent passive avoidance response may have been either nonspecific ‘freezing’ behavior following unpleasant stimulation, or inhibition specifically of movement, due to its association with shock.