bluuebunny/crossref_metadata_2025_split huggingface dataset:
The separate and combined effects of early undernutrition and environmental complexity at different ages on cerebral measures in rats
Authors: Katz H. B. , Davies C. A. 
Published: January 2005

AbstractRats were either undernourished or fed normally during the suckling period, then at 1 and 5 months of age littermates were housed in enriched or impoverished environments for 30 days. The undernutrition caused lasting reductions in the weight and size of the cerebrum and in parameters of the hippocampus, but significant deficits were not observed in the thickness and area of the occipital cortex. Differential housing differed from early undernutrition in that its largest effects were on cortical parameters, but the effects of the two conditions did partly overlap. This meant that some nutritionally induced deficits could be modified later by manipulating environmental complexity. The cerebral response of the previously undernourished rats to differential environments was not distinguishable from that of well‐fed controls on the basis of the gross anatomical changes that were measured. Furthermore, no significant differences were found between the environmental effects in young and mature rats, although the latter's response tended to be somewhat less for most parameters.
Alarm call responsivity of mallard ducklings: I. The acoustical boundary between behavioral inhibition and excitation
Authors: Miller David B. 
Published: January 2005

AbstractMallard (Anas platyrhynchos) maternal assembly calls have fast repetition rates (noteslsec,) which promote behavioral excitation in ducklings (i.e., vocalizing, approaching). On the other hand, maternal alarm calls have slow repetition rates, which promote behavioral inhibition (i.e., cessation of vocalizations, “freezing”). This study assesses the nature of the acoustical boundary separating these 2 behavioral states. Maternally naive ducklings were tested to 1 of 2 series of altered alarm calls that either increased or decreased in repetition rate every minute by 2/10 sec. Ducklings in control groups were exposed to a constant repetition rate for comparable periods of time. The inhibitory and disinhibitory responses of ducklings revealed that a relatively sharp acoustical boundary between inhibitory and excitatory repetition rates exists around 2.6 to 2.8 noteslsec. This transitional region happens to coincide with the range within which neither maternal assembly nor maternal alarm calls occur. Thus, there is a genuine match along this acoustical dimension between auditory perception of ducklings and the 2 major species‐typical maternal vocalizations of mallards.
Visceral nociception in developing rats
Authors: Bronstein David M. , Mitteldorf Phillip , Sadeghi Mina M. , Kirby Karen , Lytle Loy D. 
Published: January 2005

AbstractMaturational changes in visceral nociception were measured in developing or adult rats challenged with hypertonic saline or acetylcholine. Chemically induced abdominal constrictions were absent in rats younger than 7 days of age, regardless of the dose of hypertonic saline or acetylcholine used. Age‐related increases in the percent of animals responding, the number of abdominal constrictions emitted per responder, and total response duration occurred in animals 10‐20 days of age, until adult‐like patterns of responding were attained at the time of weaning. Additional changes in the percent animals responding, as well as in the frequency and total duration of abdominal constriction responses, were also seen in postweanling, but not in preweanling, animals. Five‐day‐old animals did emit audible vocalizations to the intraperitoneal insertion of a hypodermic needle, however, at a time when these animals failed to show observable responses to the noxious visceral stimuli. Hence, mechanisms mediating pain associated with intraperitoneal needle insertion may be functional during the first postnatal week, at a time when mechanisms mediating visceral pain appear to be immature. These differences may be caused by the differential maturation of sensory, neural, or motoric mechanisms important for hypodermic needle insertion versus visceral nociception.
Repeated failure of prenatal ACTH administration to alter masculine behavior in mice
Authors: de Catanzaro Denys , Maerz Marita D. , Heaven Roberta K. B. , Wilson Wendy 
Published: January 2005

AbstractIn four experiments, different preparations and modes of prenatal administration of ACTH all failed to produce any substantial effects upon male sexual behavior in mice. In Experiment 1, CD‐1 females implanted during the third trimester of pregnancy with osmotic pumps releasing varied dosages of ACTH1−24 produced male offspring with essentially normal copulatory behavior. In Experiment 2, prenatal injections of high doses of ACTH1−24 had no effect upon male sexual activity. In Experiment 3, osmotic pumps releasing ACTH1−39 during the third trimester of pregnancy had no effect upon sexual behavior of offspring. However, aggressive behavior was significantly reduced, relative to untreated controls, in offspring of all females implanted with pumps, including those releasing only saline. In Experiment 4, third‐trimester injections of ACTH1−39 in long‐acting gel form had no effect on the sexual behavior or aggression of offspring of C57 strain females. In most of these experiments, ACTH treatment significantly reduced body weight. These results do not confirm previous suggestions that pituitary‐adrenal hormones influence the perinatal differentiation of sexually dimorphic behavior.
Training ducklings in broods interferes with maternal imprinting
Authors: Lickliter Robert , Gottlieb Gilbert 
Published: January 2005

AbstractUnder natural conditions, if maternal imprinting is to occur it must occur in a social situation which includes the presence of broodmates. In the laboratory it has been shown that social rearing with siblings prior to maternal imprinting interferes with the establishment of maternal imprinting, whereas social experience with siblings after maternal imprinting enhances the imprinting experience. The present study examined the influence of social experience with broodmates during an imprinting trial on the establishment of a visually imprinted maternal preference in domestic mallard ducklings (Anas platyrhynchos). Twenty‐four‐hour‐old ducklings were allowed to follow a stuffed mallard hen for 30 min either individually or in a brood of four same‐aged ducklings. The birds trained alone subsequently showed an imprinted preference for the familiar mallard hen over an unfamiliar pintail hen or four stuffed ducklings in simultaneous choice tests at 48 and 72 hr after hatching. Ducklings trained with broodmates did not show a preference for the familiar mallard hen over the unfamiliar pintail hen and displayed a preference for the stuffed ducklings over the mallard hen at 48 and 72 hr choice tests. These results demonstrate that even brief (30 min) experience with siblings during a maternal imprinting trial results in peer imprinting that interferes with the establishment of maternal imprinting. These and other results of a similar sort render dubious the significance of most laboratory studies of imprinting for an understanding of such events in nature.
Maternal and nutritional contributions to infant rats' activational responses to ingestion
Authors: Bornstein Brian H. , Terry Leslie M. , Browde Joseph A. , Assimon Sue Ann , Hall W. G. 
Published: January 2005

AbstractInfant rats deprived of food, maternal care, and the opportunity to suckle display a dramatic behavioral activation and vigorously ingest when provided milk through oral cannulas. These experiments assessed which components of deprivation are important in producing these responses to milk. Nutritional deprivation alone, with or without the presence of an active maternal female, appears to be sufficient to produce ingestion. Behavioral activation, on the other hand, appears to require both nutritional deprivation and deprivation from a maternal female. The effect of maternal stimulation on later behavioral reactivity was not a function of the pups' opportunity to suckle. However, active maternal stimulation was more effective in preventing activation than was passive maternal stimulation (e.g., thermotactile and olfactory stimulation). Stimulation provided by an active, nonlactating mother was effective in preventing behavioral activation, but the effect was short‐lived, lasting only 2 hr after the pup was removed from the mother's care. This series of studies thus reveals that identified components of maternal separation have dissociable effects on appetitively motivated behaviors in infant rats.
Sapid savvy in sucklings: The effect of quinine hydrochloride on intraoral negative pressure and intake by 11–13‐day‐old rat pups
Authors: Pelchat Marcia Levin , Brake Stephen C. 
Published: January 2005

AbstractThree experiments describe the consummatory behavior of 11–13‐day‐old rat pups during and following experience with a model aversive taste, quinine hydrochloride. Pups were observed while away from the dam and while suckling. Results show that pups actively reject quinine adulterated solutions in both situations. They do so by spitting the solution from the mouth when away from the nipple and by leaving the nipple and/or decreasing their sucking effort when with the dam.
Stimulus duration as an age‐dependent factor in reflex blinking
Authors: Anthony Bruno J. , Zeigler Bonnie L. , Graham Frances K. 
Published: January 2005

AbstractAlternative hypotheses of differential development of auditory and visual systems versus temporal‐processing systems were tested to explain prior adult–infant differences in reflex blink latency. The present study removed a confound between stimulus modality and duration, present in prior work, and determined whether age interacted with modality or with duration when they were varied orthogonally. Reflexes were elicited from human adults and infants under 4 stimulus conditions: flash and click, delivered singly and in trains. Age interacted only with duration to affect latency and elicitation probability, reflex characteristics which depend on adequate triggering by a transient change at onset. In contrast, age did not interact with duration to affect peak amplitude which presumably depends on temporal integration. Findings are compatible with the hypothesis that processes or structures, specialized for differentiation of transient stimulus change, mature at a different rate than those specialized for integration of stimulus energy over time.
Olfactory influences on the ingestive behavior of infant rats
Authors: Terry Leslie M. , Johanson Ingrid B. 
Published: January 2005

AbstractTwenty‐four‐hour deprived infant rats from 1 to 12 days of age were exposed to the odor of milk, either by itself or accompanied by oral infusions of water, sucrose, quinine, or milk (Experiment 1). Pups from 3 to 9 days of age became behaviorally active, and mouthed and probed in response to the odor of milk, even in the absence of oral infusions. Six‐ and 9‐day‐old pups also increased their intake of various test solutions in the presence of milk odor. This responsiveness to milk odor was not seen in 1‐day‐old pups, and waned by 12 days of age. Other stimulus odors that were presented in the same context (Experiment 2) failed to elicit such intense behavioral activation, indicating that there was some degree of specificity in the responsiveness to milk odor. Finally, 2 manipulations that influence pups' ingestion of milk, deprivation and ambient temperature, were found to influence pups' responses to milk odor (Experiment 3).
Intersensory coordination and the effects of early sensory deprivation
Authors: Tees Richard C. , Symons Lawrence A. 
Published: January 2005

AbstractThe effect of early visual deprivation on the ability of dark‐ (DR) and light‐reared (LR) rats to learn temporal discriminations involving sounds and lights and to abstract the intersensory correspondence involving duration from initial modality‐specific training was examined in this study. While visually inexperienced DR rats were somewhat less successful in acquiring an initial discrimination involving visual events and responding to a rule reversal per se, they were as effective as their visually experienced LR counterparts in demonstrating cross‐modal transfer (CMT) to signals in a new modality. The results revealed by the investigation are discussed in terms of the consequences and lack of consequences of the manipulation of early visual experience on the ontogeny of intersensory perceptual development in mammals.
Alarm call responsivity of mallard ducklings: V. Age‐related changes in repetition rate specificity and behavioral inhibition
Authors: Miller David B. , Blaich Charles F. 
Published: January 2005

AbstractTwenty‐four‐hour‐old mallard ducklings (Anas platyrhynchos) exhibit a high degree of behavioral freezing (i.e., vocal and locomotor inhibition) upon hearing the maternal alarm call, which the hen utters when potential predators are near the nest. In this study, we assessed age‐related changes in alarm call responsivity between 12 and 72 hr after hatching. Experiment 1 revealed that, although a significant reduction in vocal activity occurred upon exposure to the alarm call at all ages tested (12, 24, 36, 48, 60, 72 hr), birds older than 48 hr exhibited lower levels of freezing than younger birds. Furthermore, 12‐hr‐old ducklings exhibited the greatest level of freezing among the younger‐aged groups. In Experiement 2, 12‐, and 72‐hr‐old ducklings were tested to variations of the alarm call that differed in repetition rate (0.2 to 2.6 notes/sec, in increments of 2/10 of a second) to ascertain whether there are age‐related changes in perceptual specificity and whether ducklings exhibit perceptual sharpening. Although older ducklings exhibited a slight shift in perceptual specificity toward faster repetition rates, they froze significantly less than younger ducklings at all repetition rates. Therefore, there was no evidence of perceptual sharpening. These data suggest that alarm call responsivity may represent an adaptation that appears to be associated with the timing of the nest exodus.
Acquisition and retention of separate elements of a conditioned olfactory discrimination in preweanling rats
Authors: Serwatka Joseph , Spear Norman E. 
Published: January 2005

AbstractAcquisition and retention of separate elements of an olfactory discrimination were tested in 15‐and 20‐day‐old preweanling rats. Four or 8 conditioning trials were given in Experiment 1. Each rat was presented one odor always followed by footshock (CS+) and another never paired with footshock (CS‐). Conditioning to both stimuli was assessed through 3 types of olfactory preference tests involving comparison between CS+ and a novel odor, CS− and a novel odor, or CS+ and CS−. The results indicated that for 15‐ and 20‐day‐olds, both stimuli become excitatory early in training; further conditioning trials diminished the excitation previously accrued to the CS−, and the olfactory discrimination became apparent. When levels of conditioning were equated, retention was tested after intervals of 4 min, 3 days, or 8 days (Exp. 2). Rate of forgetting was more rapid for the 15‐day‐olds, but both ages of subjects showed similar patterns of forgetting, which included a progressive decrease in the aversion to the CS+ but an increase in aversion to the CS−.
Gender differences in caring for infant Cebuella pygmaea: The role of infant age and relatedness
Authors: Wamboldt Marianne Z. , Gelhard Robert E. , Insel Thomas R. 
Published: January 2005

AbstractThis paper describes a three‐part study of the parenting behaviors of 6 family groups of Cebuella pygmaea (pygmy marmosets). In the first part, the parenting patterns of undisturbed family groups housed under laboratory conditions were scored throughout the first 10 weeks following the birth of their second infant(s). To further investigate the role of infant age in determining parental behavior, caretaking patterns were studied after a brief separation of infants of varying ages from their families. Finally, an unrelated infant, age 1–5 weeks, was placed inside the home cage of each family, and caretaking of this novel infant was scored. The main findings that emerged from the study were: (1) sex differences in carrying the infants were dependent upon the age of the infant, i.e., adult females were the predominant carriers of infants /3 weeks of age and males (either adult or juvenile) the main carriers for infants >3 weeks of age; (2) some caretaking behaviors, e.g., grooming and protective retrieval, were performed predominantly by the adult females throughout infancy; and (3) the relatedness of the infant, i.e., one's own vs. another's, appeared to primarily affect the behavior of adult females. In general, experimental manipulations confirmed results of the observational part of the study and thus may be useful paradigms for testing specific hypotheses about parental behaviors.
Physical stimulation reduces the brain temperature of infant rats
Authors: Sullivan Regina M. , Wilson Donald A. , Leon Michael 
Published: January 2005

AbstractPrevious work indicated that physical stimulation, such as that which mimics the stimulation pups receive from the dam, reduces pup body temperature. The present paper reports that the body and brain temperature of 5‐day‐old pups covaried under steady‐state thermal conditions, cold exposure, and warmth exposure (Expt. 1) suggesting that body thermoregulatory mechanisms may also regulate brain temperature. Indeed, physically stimulating pups decreased brain temperature in the neocortex (Expt. 2) and the olfactory bulb (Expt. 3). The mechanism for this brain temperature decrease appears to be an increase in ventilatory heat exchange, the same mechanism responsible for the decrease in body temperature. Pups increased respiration during stimulation, thereby increasing air flow to the lungs where convective and evaporative heat exchange occurred. Indeed, stimulating pups in a high‐humidity environment blocked the decrease in brain temperature (Expt. 4). The ability of physical stimulation to decrease brain temperature appears to be limited to neonatal pups, as 10‐, 15‐, and 20‐day‐old pups did not exhibit a brain temperature decrease in response to stimulation (Expt. 5).
Auditory evoked heart rate responses in pigtailed macaques (Macaca nemestrina) raised in isolation
Authors: Martin Robert E. , Sackett Gene P. , Gunderson Virginia M. , Goodlin‐Jones Beth L. 
Published: January 2005

AbstractHeart rate (HR) responses evoked by 1 sec of 85‐dB white noise were studied in 12 1‐year‐old pigtailed macaques, 6 of which were raised in social isolation and 6 with mothers and peers. Tests were given for 5 days, with 25 trials each day. Although baseline HR did not differ between groups, the pattern of change from baseline was not the same. Isolates showed only HR acceleration, returning to baseline within 10–11 sec of stimulus onset. Socially reared monkeys had a 10‐ to 11‐sec biphasic response of acceleration followed by deceleration, with subsequent return to baseline. The same group difference in HR pattern occurred when subjects were tested with a less intense 65‐dB stimulus. These findings were discussed in terms of activity, emotionality, and autonomic regulatory functions. It was concluded that early rearing experiences may affect later physiological processes involving autonomic nervous system balance. This conclusion was related to observations of persistent individual differences in HR by human children classified as inhibited.
Prenatal antagonism of stress by naltrexone administration: Early and long‐lasting effects on emotional behaviors in mice
Authors: D'Amato F. R. , Castellano C. , Ammassari‐Teule M. , Oliverio A. 
Published: January 2005

AbstractThe effects of prenatal exposure to stress and to naltrexone on emotional behaviors were studied in CD1 mice during ontogeny and in the adulthood. During ontogeny (a) lower body weights were initially found in pups born by mothers injected with naltrexone; (b) treatments did not affect sensory motor development except in the case of the cliff aversion reflex which occurred earlier in pups prenatally exposed to stress; (c) measures of ultrasonic vocalizations in stressful context showed that the amount of vocalizations emitted by pups born by stressed mothers was significantly higher than that emitted by pups born by naltrexone injected and control mothers (d) an examination of motheroffspring interactions on the very first day of observation indicated a consistent trend in stressed mothers to be more responsive to their pups. In adulthood, ultrasonic calls in courtship after short and long periods of isolation showed a time‐dependent decrease of vocalizations in males prenatally exposed to naltrexone. These results indicate that the modifications of emotionality evident during early development are directly related to the reactivity of the mothers to the experimental treatments. Moreover, the long‐term reduction of ultrasonic vocalizations in adult males prenatally exposed to naltrexone shows in these animals a lowered reactivity to stressful contexts which probably results from specific physiological alterations due to the prenatal administration of the opiate antagonist.
Associative processes in differentially reared monkeys (Macaca mulatta): Sensory preconditioning
Authors: Beauchamp Alan J. , Gluck John P. 
Published: January 2005

AbstractPast research has indicated that with ragard to performance in formal learning test situations, early socially isolated rhesus monkeys display atypical reactions to noxious stimuli, deficits in response inhibition, slower adaptation to reinforcement contingencies, and lower performance on oddity tasks. Twelve adult rhesus monkeys (Macaca mulatta), 6 who had been reared in total isolation for the first 9 months of life 19 years earlier, and 6 socially reared, were tested in a sensory preconditioning paradign. In phase I, two neutral stimuli (S1–S2) were paired in contriguous fashion; in phase II the S2 stimulus was conditioned to elicit a startle response; and in phase III the S1 stimulus was presented to assess whether an association between the two stimuli had been formed during the initial phase. Instead of a deficit, isolate subjects showed significantly more response transfer during phase III as compared to the controls. The superior performance displayed by isolates is viewed as resulting froma slower habituation to S1‐S2 stimuli during preconditioning along with the preservation of responses during testing. These findings support the motion that atypical cognitive processing across a lifespan is a consequence of early social impoverishment.
Sensory determinants of nipple‐attachment behavior in 2–4‐day‐old kittens
Authors: Blass Elliott M. , Shulekina‐Turpaeva Kira , Luschekin Vitalie 
Published: January 2005

AbstractFourteen kittens, 2–4 days of age, wee studied on their anesthetized dams for nipple attachment behavior. In agrreement with a previous report (Larson, M.A., & Stein, B. E., 1984, Dev. Psychobiol., 17; 423–436) we find that olfaction contributed rather little to nipple attachment in kittens.