bluuebunny/crossref_metadata_2025_split huggingface dataset:
Olfactory bulbectomy and nursing behavior in rat pups (Wistar DAB)
Authors: Singh Pauline Jirik , Tobach Ethel 
Published: January 2005

AbstractTo determine whether bilateral olfactory bulbectomy led to a change in nursing behavior, and thus death, we bilaterally bulbectomized (BX) pups from 14 litters at 2, 7, and 11 days of age. Litters treated on Days 2 and 7 consisted of 3 BX pups, 2 surgical control (SC) pups, and 2 handling control (HC) pups. Litters treated on Day 11 consisted of 1 or 2 BX, 1 or 2 incompletely bulbectomized pups (IBX), 2 SC pups, and 2 HC pups. These litters and 3 additional nontreated litters were observed on Days 4, 7, 10, 13, and 16. A smaller number of BX pups survived through Day 10 than SC, HC, IBX, and nontreated pups. Differential treatment of the BX pups by females or littermates was not found. The females' mammary glands were functional but the BX pup stomachs had little or no milk. The BX pups spent less time nursing and more time away from the female and their littermates than did the other pups.
Handling rabbits in infancy: In search of a critical period
Authors: Wyly Mary Virginia , Denenberg Victor H. , De Santis Darlene , Burns Joan Kennedy , Zarrow M. X. 
Published: January 2005

AbstractIn Experiment 1 rabbits were handled for the first 10 days of life while controls were not disturbed. In Experiment 2 rabbits were handled on Days 11–20. In Experiment 3 rabbits were handled on Days 1–10, 11–20, 1–20, or were not handled. Starting at 31 days the animals were given an open‐field test, a test for exploratory behavior toward novel stimuli, and a test of social behavior. The data were not consistent with the critical period concept. Instead, handling during the first and second 10‐day intervals appears to be additive and to approximate the effects of 20 days of handling.
Acute versus chronic acoustic deprivation: Effects on auditory evoked potentials and seizures in mice
Authors: McGinn Michael D. , Henry Kenneth R. 
Published: January 2005

AbstractC57BL/6J mice are not typically susceptible to audiogenic seizures, but temporary conductive hearing loss (via earplugging) can induce susceptibility in these subjects. The present study observed that a 40‐dB hearing loss, beginning at 17 days postpartum, requires 2 days before it induces susceptibility to audiogenic seizures. When this hearing loss occurred only between 17 and 21 days postpartum, seizures were maximally severe 1–2 days after earplug removal. The peak‐to‐peak amplitudes of the auditory evoked potential (AEP) were also maximal at this same time. But mice deprived of acoustic input between ages 42–46 days exhibited equally large or even larger AEP amplitudes, while not exhibiting susceptibility to audiogenic seizures. Animals at this older age were shown to be capable of convulsing, in that chronic conductive loss from 17–42 days maintained susceptibility to audiogenic seizures. The acoustic deprivation produced both behavioral (audiogenic seizures) and neural (augmented AEP amplitudes) supersensitivity to sound, but the former requires a critical period, whereas the latter does not. Some degree of residual hearing loss persisted at all ages for approximately 2 days after removal of the earplugs.
Prenatal maternal d‐amphetamine effects on emotionality and audiogenic seizure susceptibility of rat offspring
Authors: Seliger Deborah Levy 
Published: January 2005

AbstractDosages of 0, 5, and 10 mg/kg body weight of d‐amphetamine were injected subcutaneously to gravid albino rats during Days 5–9 or Days 12–16 of gestation. Offspring were assessed for water‐wading emotionality and audiogenic‐seizure behaviors. No significant differences among groups were found in defecation scores from either test. The only animals to exhibit a considerable incidence of wild‐running attacks or seizures were these whose mothers had received the placebo early in pregnancy. These differences are in agreement with most findings that indicate an enhancement of immunity to audiogenic seizure susceptibility as a function of prior stress. Maternal administration of d‐amphetamine during pregnancy apparently can produce offspring who have less susceptibility to severe emotional responses but no protection against mild expressions of emotionality.
Defensive distance and immobility in young precocial birds (Gallus gallus)
Authors: Ginsburg Harvey J. 
Published: January 2005

AbstractThe manifestation and duration of the tonic immobility reaction in 3‐day‐old chicks (Gallus gallus) was found to vary reliably as a function of the spatial proximity between the hand of the experimenter and the immobilized chick. The results of this experiment indicate that young birds are susceptible to immobility and that the maintenance of close spatial proximity is the condition necessary for the occurrence of the reaction in young precocial birds.
Voluntary exposure to light by young and aged albino and pigmented inbred mice as a function of light intensity
Authors: Wax Teena M. , Goodrick Charles L. 
Published: January 2005

AbstractYoung (5 month) and old mice (23 and 26 months) of the inbred A/J and C57BL/6J strains (N = 80) were isolated in ventilation chambers with ad lib food and water for 1 week at a time. Each animal was allowed to select its own lighting schedule by pressing one lever to turn on a light of either 10.76 or 166.40 lux illumination intensity and pressing another lever to turn the light off. Three‐way analyses of variance for Age, Strain, and Illumination effects on parameters of bar pressing, stimulus change, and light duration patterns per circadian period (24 hr) indicate that old mice are less active than young mice and the A/J mice are less active than C57BL/6J mice. Young mice spent more time in the dark than old mice and the A/J albino mice spent more time in the dark than did the C57BL/6J pigmented mice. Other age and strain differences were noted as well and are discussed with respect to some theories of light exposure by nocturnal animals.
Effects of age and genotype on acquisition of an active avoidance response in mice
Authors: Stavnes Karen , Sprott Richard L. 
Published: January 2005

AbstractTwo experiments were conducted in which inbred C57BL/6J and DBA/2J mice were trained in an active avoidance jump‐up task under distributed practice conditions at a variety of ages comprising a large part of their life‐span. DBA/2J mice were found to be basically an escaping strain and exhibited little change in behavior as a function of age. C57BL/6J mice developed consistent avoidance behavior when training was initiated at 31–36 days of age. Avoidance behavior appeared to reach a peak in the 45–day‐old group and progressively decreased in 145‐ and 560‐day‐old groups. Increased footshock intensity in old DBA/2J mice enhanced escape responding without increasing avoidance responding. Increased footshock intensity in old C57BL/6J mice enhanced avoidance responding.
The development and modification of object preferences in domestic white leghorn chicks
Authors: Einsiedel Albert A. 
Published: January 2005

AbstractThis study examined in domestic chicks the time‐course of adaptation to a new object after having established strong preferences for a previous stimulus (during the first 3 days of life). By interchanging the stimuli to which the animal was exposed, and by confining the animal exclusively with the new object for some period of time, the new preference was expected to develop as a function of the duration of exposure. The results confirm that expectation with a monotonic increase in preference as a function of hours of exposure. The establishment of a preference for the new object was rapid, as indicated by a significant shift in preference after 5 hr.
Daylength and sexual maturation in female house mice
Authors: Drickamer Lee C. 
Published: January 2005

AbstractA series of 4 experiments investigated the relationship between daylength and sexual maturation in female house mice. Mice reared in constant light matured significantly later than mice maintained under photoperiods involving 0, 6, 12, or 18 hr of light/day. Results of an experiment involving cross‐classified combinations of pre‐ and postweaning photoperiods revealed that only the postweaning photoperiod treatment was a significant factor influencing the attainment of puberty. Studies of body growth, food consumption, and wheel‐running activity in young females housed under different photoperiods indicated that mice kept in constant light grew more slowly during the first 10 days after weaning, generally consumed more food than mice at other photoperiod conditions, and failed to exhibit regular daily activity patterns like those of mice maintained under photoperiods of 0 or 12 hr of Night/day. Constant illumination apparently disrupts the normal physiological and behavioral activity rhythms and delays the attainment of sexual maturity.
Developmental patterns of seizure susceptibility in inbred strains of mice
Authors: Deckard Betty S. , Lieff B. , Schlesinger K. , Defries J. C. 
Published: January 2005

AbstractSamples of mice from each of 6 inbred strains were tested for audiogenic and electroconvulsive seizures at 5 ages (14, 21, 28, 35, and 42 days). A moderately large within‐strain correlation (.67) was found, indicating that developmental patterns of susceptibility to audiogenic and electroconvulsive seizures are similar within each strain. The finding of an even larger between‐strain correlation (.91) indicated that strains which are highly susceptible to audiogenic seizures are also likely to be highly susceptible to electroconvulsive seizures.In a 2nd experiment, whole brain norepinephrine and serotonin were assayed in each of 5 inbred strains at 21 and 42 days of age. Results were consistent with the hypothesis that levels of these amines are inversely related to seizure susceptibility. Mice from strains which were susceptible to seizures at 21 days of age had significantly lower levels of norepinephrine and serotonin in brain than did 42‐day‐old, seizure‐resistant animals.
Absence of effects of corticosterone given at 22 days
Authors: Howard Evelyn 
Published: January 2005

AbstractMice given a single large dose of corticosterone at 2 days of age, and tested when adult, have shown lasting alterations in operant behavior, associated with reductions in cerebral weight and DNA content. When mice were given corticosterone at 22 days, no changes appeared in cerebral weight, DNA, or in operant behavior, but an apparent decrease did occur in open‐field activity. The results suggest that the effects of corticosterone treatment at 2 days on the developing brain are mediated by one or more types of sensitivity to the steroid that have been largely lost by 22 days.
Rapid changes in cerebral blood flow and initial visual experience in the developing chick
Authors: Bondy Stephen C. , Purdy Janet L. 
Published: January 2005

AbstractA single eye of young chicks was sewed shut for various times. Regions contralateral to and primarily or secondarily innervated by the sutured eye had a reduced rate of cerebral blood flow in comparison to the corresponding ipsilateral regions. However, upon reopening the sutured eye after 2 days, these contralateral regions (optic lobes and cerebral hemispheres) exhibited a rapid increase in cerebral blood flow to a level significantly above that in control ipsilateral areas. The duration of this effect was considerably prolonged in chicks that were monocularly sutured immediately after hatching without prior exposure to light. Chicks that had 1 week of normal vision before monocular suture did not show this overcompensatory effect. If the period of monocular suture was extended to 7 days before restoration of vision to the occluded eye, the overcompensatory vascular effect was delayed. The maximal effect was apparent only upon the 1st exposure of an eye to major visual input. A possible relation exists between this rapid increase in regional blood flow and the period when visual imprinting could normally be expected to be maximal.
Peculiarities in the changes of catecholamine level in the brain, blood, and adrenals of dogs and rats in ontogenesis
Authors: Rozanova V. D. , Khodorova N. A. 
Published: January 2005

AbstractThe norepinephrine content of the whole brainstem and of its differnt parts and the epinephrine and norepinephrine (NE) content in the blood and adrenals in dogs and rats during ontogenesis were studied.The catecholamine (CA) level in the blood and different parts of the dog brainstem increased to the age of 20‐30 days and then decreased. The NE value of the whole dog brainstem increased to the age of 9‐30 days, and then decreased. The content of NE of the rat brainstem increased to the age of 120 days and then decreased. The amount of CA of the dog and rat adrenals increased progressively from birth to adulthood. The CA brain and adrenal level of dogs during postnatal ontogenesis was lower than in rats.
The organization of sleep and wakefulness after maternal separation in young rats
Authors: Hofer Myron A. 
Published: January 2005

AbstractTwo‐week‐old infant rats were studied before and after 24 hr of maternal absence. This experience produced an increase in time spent awake, a reduction in time spent in paradoxical sleep (PS), and an increased frequency of state transitions with more frequent and shorter periods of both slow‐wave sleep (SWS) and PS. Body movements were increased and nonnutritive sucking decreased during PS after separation. Other aspects of sleep organization were relatively stable: the pattern of probability of direction of state transitions, the integration of the physiological and behavioral determinants of state, the pattern and amount of nonnutritive sucking, and the underlying PS cycle period. These findings, and the results of 2 control experiments, suggest that some aspects of the prolonged absence of the mother produce a shift in the infant'apos;s central neutral state regulation through processes yet to be understood.
The behavioral effects of prenatal hypoxia in the rat
Authors: McCullough Maurice L. , Blackman Derek E. 
Published: January 2005

AbstractPregnant rats were exposed to an oxygen depleted atmosphere (13% oxygen in nitrogen) at normal pressure in 2‐hr daily sessions extending over approximately the last 14 days of pregnancy. Their progeny were compared with control progeny in terms of age of eye‐opening, open‐field behavior, and Hebb‐Williams maze problem solving ability. The groups were not distinguishable by their performance in the open‐field, but the experimental animals opened their eyes significantly earlier and made significantly more errors on Hebb‐Williams maze problems.
Motor reactions during the antenatal period correlated with the periodic change in the activity of the cardiovascular system
Authors: Arshavsky I. A. , Arshavskaya E. I. , Praznikov V. P. 
Published: January 2005

AbstractA connection between the periodic appearance of vagal bradycardia and of intrauterine large‐amplitude respiratory movements, as well as the appearance of generalized jerky‐type and more sustained extensor motor reactions, has been established in experiments on dog fetuses connected with the mother through the umbilical cord. Brief vagal bradycardia also arises immediately after completion of these reactions and is an analogue of the vagal phase in adults after motor activity. These correlated phenomena are caused by periodic reversible mild hypoxemia which through the chemoreceptors of the sinocarotid zone stimulates the centers of vagal innervation of the heart and the centers of innervation of skeletal muscles. These phenomena disappear when the mother inhales a gas mixture containing less than 14‐15% oxygen or greater than 50‐60% oxygen, as well as when the mother is under deep anesthesia.
Reaction time and the psychological refractory period in children and adults
Authors: Surwillo Walter W. , Titus Thomas G. 
Published: January 2005

AbstractThe psychological refractory period–the prolonged reaction time RT to the second of 2 closely‐spaced stimuli–was investigated in groups of 13 children and 13 adults. Subjects responded as fast as possible to the 2nd of 2 loud clicks that were presented after a soft click which served as a ready signal. The inter‐stimulus interval ISI, or time between loud clicks, was investigated as an independent variable. The results for ISIS of 50, 100, 250, and 500 msec confirmed the existence of an inverse relationship between RT and ISI. In accordance with the hypothesis investigated, RT was more prolonged in children than in adults as ISI decreased. Findings were consistent with the view that refractory period RP of aninformation‐processing element in the central processor is longer in children than in adults. A single‐channel model of information processing was proposed which could explain the inverse relationship between RT and ISI; could account for the slope differences between the RT vs ISI curves from children and adults; and could account, in part, for the overall longer RTs of children than of adults.
Actions of atmospheric ionization on spontaneous activity of an amphibian larva
Authors: Olivereau Jean‐Michel , Aimar Christian 
Published: January 2005

AbstractIn Pleurodeles waltlii (Urodela) larvae, spontaneous activity and the tendency to leave water are significantly influenced by artificial air ionization. Atmospheric ions of negative and positive polarities have opposite effects: the latter reduce spontaneous activity by 48% whereas negative ions increase it by 39%. This difference must be considered the result of a specific behavioral effect rather than attributable to the stage of development of the larvae. A comparison of our results with data in the literature indicates that the action of the air ions on amphibian activity may involve the modulation of serotonin and prolactin releases.
Ontogeny of behavior in two inbred lines of selected mice
Authors: Van Abeelen J. H. F. , Schoones A. H. 
Published: January 2005

AbstractThe development over 11 ages of 14 reflex responses, 26 behavioral components, jumpiness, and left‐right discrimination learning was studied in 2 strains of mice genetically selected for high (SRH) and low (SRL) rearing response frequency. Significant age‐dependent differences between the strains were found mainly, but not exclusively, in the behavioral components, e.g., rearing, jumping, scratching, defecating. Two‐week‐old pups of both strains showed good acquisition and retention in learning tests without shock, but the „jumpy”︁ behavior disturbed performance to a certain degree in the SRH strain. Although less active initially, SRH mice were ahead at later developmental stages. Whether these differences are determined by the gene controlling rearing frequency or by other genes remains undecided.
Effects of thyroxine on infant development of undernourished rats
Authors: Jen Catherine Kai‐Lin , Wehmer Francine 
Published: January 2005

AbstractThe rehabilitative effects of exogenous thyroxine on infant development of undernourished animals were examined. Thyroxine injection accelerated the rate of body growth, age at eye opening, tooth eruption, and several emitted behaviors in undernourished infant animals. The data indirectly support previous findings that undernutrition induces hypothyroidism and that exogenous thyroxine might be an effective rehabilitative agent.
Mirror‐image response during the first two years of life
Authors: Schulman Allan H. , Kaplowitz Cheryl 
Published: January 2005

AbstractChildren aged 1–24 months viewed themselves in planar or distorted mirrors that were either clear or partially occluded. Analysis of videotaped records revealed that interest in viewing one's face did not vary with age among the 1‐ to 24‐month‐old subjects. All performed the simple behaviors of observing themselves although the older ones performed more complex (related) behaviors. Neither the flat nor the distorted mirror exposure was preferred suggesting that the infant observes the general configuration of the face for its intrinsic interest. Specific developmental trends were noted in the kind and amount of activity during the 1st 2 years of life culminating in a sequence of behaviors that suggested self‐recognition.
Paternal effects on the development of social behavior in Mus musculus
Authors: Smith Meredith L. , Simmel Edward C. 
Published: January 2005

AbstractIn order to extend the determination and description of effects of the father's phenotype on the development of social behavior in male mice, we tested 24 males from each of 2 highly inbred strains of Mus musculus, A/J and C57BL/6J. Approximately 1 week before the birth of the subjects, we replaced natural fathers with a foster parent such that, within each strain, 8 subjects had preweaning experience with same‐strain males, 8 with other‐strain males, and 8 with same‐strain females, in addition to their natural mothers. Observations of social behavior were conducted at 21, 50, and 60 days of age. The results showed effects of the foster parent's phenotype on the development of social exploration in both strains and, possibly, on agonistic behavior in C57BL/6J mice. The different effects in the 2 strains indicate mechanisms dependent on genotype.
Is hippocampal function in the adult rat impaired by early protein or protein‐calorei deficiencies?
Authors: Hall Robert D. 
Published: January 2005

AbstractMuch of the development of the rat's hippocampal formation occurs postnatally which suggests that this structure, like the cerebellum, may be especially vulnerable to early postnatal malnutrition. Radial‐maze performance and spontaneous alternation, two kinds of behavior requiring the integrity of the hippocampus, were assessed to determine whether hippocample function in the adult rat is mipaied as a result of protein restriction in either the prewaning, the postweaning or both stages of development. In three experiments the perormance of protein‐malnoruished rats in 8‐ and 12‐arm mazes did not differ significantly from that of well‐nourished rats. In a fourth experiment levels of spontaneous alternation in protein‐malnourished rats were like those of normal well‐nourished animals. Thus, The present experiments provide no evidence that hippocampal function is impaired as a consequence of early experiments provide no evidence that hippocampal function is impaired as a consequence of early protein deprivation. For the most part, a critical review of earlier studies of undernourished rats supports a similar conclusion.
Perceptual imprinting: Genetic influences and genotype‐environment interactions
Authors: Kovach Joseph K. , Wilson Gregory 
Published: January 2005

AbstractOne‐day‐old visually naive and experienced quail chicks (C. coturnix japonica) were mass‐screened for approach preferences by pairs of stimuli that were identical in size and luminance but different in color, or patter, or both color and pattern Subjects were drawn from the 18th generation of quail lines that were bidirectionally selected for color preferences, and from and unselected genetic control line. Experience consisted of 12 hr of unreinforced perceptual exposure to colored or white stimuli, with and without associated pattern. Data indicated strong genetic influences in the preferences of colors, which were partially generalized unselected preferences between colors and patterns. Joint exposure to color and pattern resulted in selective learning of color but not pattern. Systematic variations in postexposure choices between composite stimuli of colors and patterns were traced to variations of genotype, experience, and genotype‐experience interactions.