bluuebunny/crossref_metadata_2025 huggingface dataset:
The relationship between sucking and grasping in the human newborn: A precursor of hand‐mouth coordination?
Authors: Brown Josephine V. , Fredrickson W. Timm
Published: January 2005

The relationship between grasping and sucking, a possible precursor of hand‐mouth coordination, was examined in human newborns of varying gestational ages. Grasping was elicited by rapidly titling the infant backwards while he rested on a padded board and held a grasp bar. Infants were titled 4 times under each of 3 conditions: grasping, sucking, and grasping‐while‐sucking. The dependent variables were strength and duration of grasp and frequency and amplitude of sucks during the 15 sec following the tilt. The results indicated that grasping did not affect sucking but that sucking increased the strength and the duration of the grasp. Furthermore, either response system was more highly correlated with indices of maturity of the central nervous system when elicited in the presence rather than the absence of the other. We conclude that in human newborns sucking may be dominant over grasping but that both are part of an integrated system which may form the basis for the development of hand‐mouth coordination.
An observational study of caretaking behavior of male and female mice housed together
Authors: Priestnall Robin , Young Susan
Published: January 2005

A time‐sampling procedure was employed to examine the caretaking behavior of male mice housed with lactating females and their litters, and to investigate the effects of the male's presence on the behavior of the female. The incidences of 14 categories of behavior were recorded over 20 hr distributed throughout the period of lactation. The development of litters was monitored by regular weighing. The results show, contrary to earlier findings, that males display just as much caretaking behavior as females. Differences in other forms of behavior can be related to the increased nutritional needs of the nursing mothers. The presence of the male seems to have very little influence on the behavior of the female and no effect at all upon the physical development of the litter.
Individual differences during the development of the domestic chick's attraction toward intermittent light
Authors: Simner Marvin L.
Published: January 2005

Stable and persisting individual differences occur in the domestic chick's attraction toward normally preferred rates of intermittent white light in the vicinity of 4 flashes per second during the period around hatching when this preference develops. These differences are not linked to fluctuations in the test environment, high levels of indiscriminate responding toward flicker in those most attracted, the presence of an alternate rate preference in those least attracted, or to differences among chicks in arousal level or locomotor ability.
Specificity of litter odors in the control of home orientation among kittens
Authors: Freeman Natalie C. G. , Rosenblatt Jay S.
Published: January 2005

The specificity of maternal‐home cage odors governing home orientation was tested in 8‐ to 11‐day‐old kittens. Kittens were first tested for home orientation from the adjacent corner in their own home cages and cages of other mothers with litters of the same age. The majority of kittens oriented successfully in their own cages but not in strange mothers' cages. They then lived for 48 hr in the strange mothers' cages. At the end of this time they showed no improvement in orientation in their own home cages. Moreover, after an additional 24 hr in their own home cages they showed no improvement in their own home cage. Home orientation involves 2 odor components: 1 general to different mothers and 1 specific to each mother.
The onset of rhythmic activities in normal and high‐risk infants
Authors: Field Tiffany , Ting George , Shuman H. H.
Published: January 2005

The onset of rhythmic activities was compared for 2 groups of high‐risk infants (a preterm Respiratory Distress Syndrome and a postterm postmature group) and a normal term group over their 1st year of life. The postterm postmature group experienced earlier onsets of rhythmic activities. The preterm RDS group showed delays in the onset of rhythmic activities, but when a correction was made for the prematurity, did not differ from the other groups. These differences suggest that the onset dates for rhythmic activities are not affected by the perinatal complications of RDS or postmaturity, but are related to gestational age differences. A comparison of the 3 groups on Bayley 1st‐year motor skills revealed group differences even after an adjustment for gestational age differences, suggesting that the development of motor skills, unlike the development of rhythmic activities, may have been affected by these perinatal complications.
Effects of the duration of dark rearing on visually guided behavior in the kitten
Authors: Crabtree John W. , Riesen Austin H.
Published: January 2005

Forty‐eight kittens were dark reared or light reared from birth for 1 to 8 months and formed 6 age groups. Following rearing the kittens were examined daily in several tasks of visually guided behavior. Compared to younger dark‐reared groups of kittens, older deprived groups showed longer acquisition times for visual placing to a surface, visual tracking, visually guided reaching to a serrated edge and moving object, and visually guided locomotion on elevated platforms. After dark rearing durations of 3 months or longer, deprived groups displayed overall deficiencies in obstacle avoidance during their 1st postdeprivation month. The older dark‐reared groups gave some indication of a direct relationship between duration of dark rearing and both delay in acquisition times for the visually guided behaviors and deficiency in obstacle avoidance. One interpretation of the results is that during dark rearing the kitten may acquire nonvisual behaviors which could interfere with and prolong its development of visually guided behavior subsequent to deprivation.
Postnatal undernutrition in rats: Attempts to develop alternative methods to food deprive pups without maternal behavioral alteration
Authors: Codo W. , Carlini E. A.
Published: January 2005

Two methods were investigated as attempts to undernourish rat pups without the disturbances in maternal behavior that accompany the procedures used to date for this purpose. In the 1st method, a litter of 12 pups was raised by both a lactating mother and a “sensitized” female. The sensitized female was provided under the assumption that she could correct for the deficit in maternal care when 1 mother raises a large litter. The results showed that the pups raised by the 2 females were constantly removed by the females from each other's nests; the females engaged in constant fighting and showed altered maternal behavior. As a consequence the pups lost more weight than control underfed young. The 2nd method consisted of removing 6‐8 nipples from virgin females which were mated 10 days later. After delivery these females raised litters of 6 pups. Their maternal behavior was equal to that of unoperated controls, and at weaning the pups had 20–50% less body weight. This method could be useful to study undernutrition effects on behavior, without confounding experimental variables.
Lateral differences and head‐turning responses to somesthetic stimulation in premature human infants
Authors: Lewkowicz David , Gardner Judith , Turkewitz Gerald
Published: January 2005

Head‐turning responses to somesthetic stimulation of the perioral region were studied at weekly intervals in 25 prematurely born infants. No regular changes associated with age were evident. The premature infants were more likely to turn towards than away from a stimulus; however, they were less so than are full‐term infants. The infants were as likely to turn towards the stimulus when it was on the left as when it was on the right; however, they were more likely to turn away from a stimulus on the left than on the right. Comparisons with full‐term infants indicated reduced lateral differences in responding. Such a reduction is in sharp contrast with the previous finding of marked postural asymmetry in a comparable sample of prematurely born infants. These data indicate a possible sequence in the development of head‐turning responses to somesthetic stimulation and the assumption and maintenance of an asymmetrical head posture which consists of (1) a right‐turning postural bias, (2) contralateral responding to somesthetic stimulation, (3) lateral differentiation of contralateral responding, (4) ispilateral responding, and (5) lateral differentiation of ipsilateral responding.
Pavlovian excitation, internal inhibition, and their interaction with free operant avoidance as a function of age in rats
Authors: Niemi R. Ronald , Thompson William R.
Published: January 2005

The central hypothesis was that, in young as compared with adult rats, Pavlovian excitation is weaker and extinguishes more slowly, whereas internal inhibition is weaker but extinguishes more rapidly. In Experiment I, the suitability of free operant (Sidman) avoidance as a baseline for measuring Pavlovian effects was assessed in 5 age groups between 19 and 98 days of age trained in a shuttle box. Although clear age‐related increases were evident in avoidance capacity, efficient “high criterion” avoiders were found in all age groups, indicating that the response was suitable. In Experiment II, groups of 26‐, 38‐, and 95‐day‐old rats first received Pavlovian aversive excitatory and differential inhibitory conditioning, or the conditional stimuli and shock randomly, or no treatment. Three days later they received free avoidance training. Prior Pavlovian conditioning facilitated subsequent avoidance learning in young subjects, but depressed it in adults. Among “high criterion” avoiders, such effects were absent. Following the avoidance training phase, 3 age groups of matched “high criterion” avoiders received conditioned stimuli superimposed on the baseline (a conditioning test). These results confirmed the central hypothesis.
Interaction of separation discomfort with contact comfort and discomfort in the dog
Authors: Gurski John C. , Davis Kenneth , Scott J. P.
Published: January 2005

This experiment concerns 2 issues: the time of onset of the process of social attachment in the dog, and the nature of the interaction between the emotion of separation distress and that caused by discomfort. The subjects were 48 puppies from 4 genetic backgrounds: beagles, Telomians, and their reciprocal F1 hybrids. Puppies were divided into 4 groups and isolated for short periods under comfortable and uncomfortable conditions beginning at 3, 11, 17, and 25 days from birth. The dependent variable was distress vocalization during a 10‐min period. Separation distress did not occur before 11 days and remained at a low level until 21 days, when it rose rapidly. The process of attachment is thus initiated in the transition period but does not reach a high level until some 2 weeks later. Interaction between the 2 kinds of affect is compatible and additive.
Home‐orienting behavior in rat pups surviving postnatal or intergenerational malnutrition
Authors: Galler Janina R.
Published: January 2005

Growth and home‐orienting behavior were studied during the 1st 12 days of life in 3 groups of rat pups: (1) those with intergenerational malnutrition; (2) those with postnatal malnutrition produced by cross‐fostering pups born of well‐nourished mothers to lactating females maintained on a low‐protein diet; and (3) well‐nourished control pups. Growth of pups was impaired in both malnourished groups, and eye‐opening was similarly delayed. On tests of homing behavior, both malnourished groups were impaired to a similar extent and were less likely to find their way to the nest than were control pups. However, survival rates were significantly lower (50%) in the postnatally malnourished group but not in the intergenerationally malnourished group (73%), as compared with controls (100%). These findings suggest that adaptation occurs to long‐term malnutrition with increased survival. However, physical characteristics and homing behavior in early life are not distinguishable in those surving short‐ or long‐term malnutrition. This is in contrast to the finding of more severe behavioral deficits in later life among rats subjected to many generations of malnutrition than among those malnourished for only 1 generation.
Developmental, behavioral, and pharmacological characteristics of rat offspring from mothers receiving ethanol during gestation or lactation
Authors: da Silva Vilma Aparecida , Ribeiro Maria Judith , Masur Jandira
Published: January 2005

Ethanol solution (10 or 20% v/v) sweetened with .4% saccharin was given to female rats as the only source of fluid. In the 1st experiment the administration was throughout the gestation period. Developmental, behavioral, and pharmacological tests were performed with the offspring. Litters born from females of the experimental group showed a decrease in the mortality rate induced by pentylenetetrazol, in comparison with either pair‐fed controls or an ad libitum control group. No other differences were detected. In the 2nd experiment the administration was throughout the lactation period. Pups raised by lactating mothers receiving ethanol showed a significant decrease in weight gain. Also, the maternal behavior of the ethanol‐treated mothers, measured by nest‐building and retrieval activities, showed a significant decrease when compared to pair‐fed controls.
Age group differences in bovine investigatory behavior
Authors: Murphey Robert M. , Duarte Francisco A. Moura , Novaes Washington Coelho , Penedo Maria Cecília Torres
Published: January 2005

The general relationship between age and investigatory behavior in mammals, and perhaps other taxa, is probably an inverted U‐shaped function, but is said to be a negative correlation in bovines. In Observation Set 1,5 developmental levels of domestic cattle were compared in their responsiveness to a novel stimulus in the form of a person lying on the ground. The age group‐behavior relationship approximated an inverted U. In Observation Set II, 3 developmental levels were compared and the animals' responses to a ball and to the reclined figure of a person were studied. Qualitatively, the cattle reacted similarly to both the inanimate and the human objects; again, the relationship between age and investigatory tendencies appeared to be an inverted U‐shaped function for both stimuli.
Ethanol during weaning induces a transient susceptibility to audiogenic seizures in Rb mice
Authors: Schreiber Robert A. , Lehmann Alice
Published: January 2005

Ethanol leads to 1–2 days of susceptibility to audiogenic seizures in mice normally not susceptible if it is administered during the transition from suckling to dietary self‐sufficiency. This demonstrates a developmental period of responsiveness to ethanol, and may provide evidence for an energy‐reserve hypothesis of susceptibility to audiogenic seizures.
Behavioral deficit in phenylketonuric rats: Role of aromatic acid metabolites of phenylalanine
Authors: Kaplan Harriett , Triano Teresa , Donadio Michael
Published: January 2005

To investigate the relationship between the biochemical and behavioral deficits in phenylketonuria (PKU), we treated rats from Postnatal Days 2 through 21 with p‐chlorophenylalanine plus L‐phenylalanine to simulate PKU or with one of the following aromatic acid metabolites of phenylalanine: phenylacetate, phenylpyruvate, phenyllactate, and mandelate. Behavioral tests were begun at about 9 weeks of age. Differences between experimental and control animals were found only in the water maze and in the open field. In the former, PKU rats required significantly more trials to reach criterion than controls. None of the single metabolite‐treated groups exhibited a similar learning deficit. In the open field, PKU and mandelatetreated rats were hypoactive compared with controls, whereas phenylacetate‐ and phenylpyruvate‐treated rats were hyperactive. These results demonstrate a lack of congruence between morphological and behavioral effects of treatment, suggesting that performance deficits in PKU rats may be due to interactive effects of 2 or more metabolites.
Visual discrimination in rats: The effects of rehabilitation following intergenrational malnutrition
Authors: Galler Janina R.
Published: January 2005

The effect of rehabilitation following intergenerational malnutrition in rats was observed using 3 tests of visual discrimination (Lashley tests). The following groups were studied at 3 months of age: animals nutritionally deprived of protein for many generations (intergenerational malnutrition), those from the same stock rehabilitated for 1 to 2 generations at an adequate protein level, and controls from a stock never exposed to malnutrition. Males rehabilitated for 2 generations showed some improvement in performance in the Lashley tests, but did not attain the level of well‐nourished controls. In agreement with the earlier data, females were less susceptible to behavioral deficits from intergenerational malnutrition and recovery was observed after 1 generation of rehabilitation. Growth of both males and females rehabilitated for 1 or 2 generations was superior to that of control rats.
Experiential influences on the development of huddling preferences and “sibling” recognition in spiny mice
Authors: Porter Richard H. , Tepper Vicki J. , White David M.
Published: January 2005

The role of experience in the development of huddling preferences and sibling recognition by spiny mouse (Acomys cahirinus) weanlings was investigated. In the 1st experiment, pups separated from their littermates and fostered onto unfamiliar females (and their offspring) on the day of birth, Day 10, or Day 20, subsequently showed preferential huddling with their foster littermates. Huddling by biological siblings was as infrequent as huddling by unrelated, unfamiliar agemates. The 2nd study revealed that the mother may play a role in the ontogeny of sibling recognition, possibly through distinctive labeling of her offspring. We conclude that recognition of littermates develops through experience in the home cage in the absence of an inborn ability to recognize one's biological siblings.
Ontogeny of hoarding in the golden hamster: The development of motor patterns and their sequential coordination
Authors: Etienne Ariane S. , Emmanuelli E. , Zinder M.
Published: January 2005

The hoarding behavior of 4 litters of Golden hamster pups (n = 3) was observed every 2nd day between the ages of 13 and 47 days (2 litters) or 13 and 55 days (2 litters). Each litter lived with the mother until Day 30; then the pups were put in social isolation. Immature forms of pouch filling and emptying, which were not integrated into coherent behavior sequences, appeared from the beginning of the observation period. Coordinated hoarding trips were shown from Day 21 onwards, once the motor patterns of inserting and extracting food had gained their definitive form. The development of hoarding was correlated with the animal's body weight and therefore with maturational factors. Mature hoarding behavior was greatly enhanced by the subject's separation from its family unit.
Brood patch function for the ventral scent gland of the female mongolian gerbil, Meriones unguiculatus
Authors: Kittrell E. Melanie W. , Gregg Barbara R. , Thiessen Del D.
Published: January 2005

Infants of gerbil mothers whose ventral scent gland had been excised were compared on a number of developmental indices with pups of mothers who had had an equivalent section of lateral skin removed. The removal of the mother's ventral scent gland retarded the offsprings' pattern of ultrasounding during the 1st 21 days of development. In addition, infants from such mothers showed a retarded righting reflex. Inhibitions in the developmental behavior of gerbil pups might have resulted from less effective heat transfer during mother‐pup contact. Indeed, excision of the gland resulted in lower ventral temperatures. The duality of function of the gland as an odor source for communication and as a heat source for offspring development suggests integrated communicative and thermoregulatory processes.
The role of perioral sensation in nipple attachment by weanling rat pups
Authors: Kenyon C. A. P. , Keeble S. , Cronin P.
Published: January 2005

Injecting .05 ml of 1% lidocaine into each vibrissal pad, or cutting the infraorbital nerves, abolished nipple attachment in weanling Wistar rat pups. Nipple attachment recovered following infraorbital section. Injecting the local anesthetic intraperitoneally, or into the region of the masseter muscles, did not disrupt attachment, indicating that the effect of the drug on suckling was specific to the site of injection and could not be attributed to systemic toxicity or paralysis of the masseter muscles. Performance on an olfactory‐guided orientation task was not disrupted by lidocaine, indicating that the drug did not render pups anosmic. Tactile sensation in the vibrissal pads, rhinarium, and upper lip was abolished after injecting the drug into the vibrissal pads. Vibrissal movement was absent following injection of lidocaine into either the vibrissal pads or the region of the masseter muscles. Shaving the vibrissae did not disrupt nipple attachment. The results are interpreted as suggesting that the nipples' textural qualities elicit attachment in weanling pups.
Acquisition and waning of exposure–induced attraction to a nonnatural odor in rat pups
Authors: Galef Bennett G.
Published: January 2005

The present experiments examine acquisition and waning of exposure‐induced attraction to a nonnatural odor in rat pups. I found that (1) acquisition of attraction induced by experience of an odor associated with the mother (M‐E) and of attraction induced by experience of an odor in the general environment (S‐E) had similar time courses and were of similar magnitude in pups < 20 days of age; (2) waning of S‐E‐induced attraction to a nonnatural odor was far more rapid than waning of M‐E‐induced attraction; (3) M‐E and S‐E to an odor were less effective in pups > 20 days of age than in pups < 20 days of age; and (4) although pups > 20 days of age receiving M‐E to an odor exhibited enhanced attraction to that odor, pups of equal age receiving S‐E to the same odor did not.
Behavior and physiology in young bonnet monkeys
Authors: Reite Martin , Short Robert
Published: January 2005

We studied behavioral development in 12 mother‐reared social‐group‐living bonnet macaque (M. radiata) monkey infants during the first four months of life. Physiological data was subsequently recorded from a subset of six using implantable biotelemetry. We compared these data to similar data previously collected in the same manner from similar age social group living pigtail macaque (M. nemestrina) infants. Bonnet infants were more active and apart from mother more throughout development. While in physical contact with mother, however, they were more likely to be enclosed if they were bonnets, but only in proximity or passively supported if they were pigtails. Bonnets also had more social contact with other adults.

Mean day and night heart rate and body temperature, heart rate and body temperature circadian rhythms, and most nocturnal sleep variables were virtually identical in bonnets and pigtail infants. These findings suggest that developmental differences in social behavior in two closely related species of macaque monkey need not be accompanied by differences in physiological patternig.
Does behavior contingent stimulus movement enhance filial imprinting in Japanese quail?
Authors: Cate Carel Ten
Published: January 2005

Japanese quail chicks were exposed for 2.5 hrs to either a white or a normal stuffed adult conspecific (= model). During this period the model was either nonmoving or it moved for short periods. This movement could be contingent or noncontingent upon distress calls of the chicks. In each condition, exposure led to a significant preference for the familiar model over the nonfamiliar one during a 10‐min choice test. Chicks exposed to a nonmoving model had the weakest preference for the familiar model, whereas this preference was strongest in chicks exposed to the contingent moving model; the preference of the chicks exposed to the noncontingent moving model was in between. The results indicate that the extend to which stimulus movement enhances filial imprinting depends on the relation between the chicks behavior and the timing of the stimulus movement. However, it is not clear yet whether the effect arose because the chicks perceived the contingency between the stimulus movement and their behavior or by another mechanism.
Influences of the early olfactory environment on the survival, behavior and pituitary‐adrenal activity of caesarean delivered preterm rat pups
Authors: Smotherman William P. , Robinson S. R. , La Vallee P. A. , Hennessy M. B.
Published: January 2005

In a first experiment, vaginally delivered Day 21 and Caesarean delivered Day 20 and Day 21 rat pups were isolated in the presence of various odorants or no odorant for 1 hr immediately following birth. For Day 20 pups, exposure to novel mint odor resulted in higher mortality during isolation than did exposure to the odor of amnion/placenta. In the preterm pups, whole body corticosterone levels were higher in all isolation treatments than they were immediately following birth. For Day 21 pups, isolation treatments had no effect on corticosterone concentrations, but overall, corticosterone levels were higher following Caesarean section than they were following vaginal delivery. A second experiment replicated the mint odor‐induced increase in mortality and revealed a lower activity level in preterm pups exposed to mint odor than in those exposed to the odor of amnion/placenta. Mechanical movement of the pups during exposure eliminated the effects of mint odor on mortality and activity. There was a positive correlation between corticosterone concentrations and pup activity during isolation. These results demonstrate potent influences of seemingly minor changes in early sensory stimulation on the preterm pup. The paradigm might provide a useful animal model for studying the effects of variations in ambient stimulation on premature infants.
Isolation distress in two‐week‐old rats: Influence of home cage, social companions, and prior experience with littermates
Authors: Hofer Myron A. , Shair Harry N.
Published: January 2005

Behavioral and autonomic manifestations of acute isolation distress were studied in 2‐week‐old rats under novel and home‐cage conditions. Levels of ultrasonic vocalization, heart rate, self‐grooming, and rises were higher in novel surroundings, while locomotion and digging were more frequent in home cages. Next, we found that a group of 8 unanesthetized agemate pups was just as effective as an anesthetized dam in reducing (by 80–90%) all behaviors of isolated pups in novel surroundings. Finally, singletons without littermates during postnatal days 7–14 showed normal isolation responses, and these were as effectively alleviated by littermates as those of normally reared pups. Thus, isolation distress in rats this age is a complex response, modulated over time by aspects of the pups' environment and virtually prevented by the presence of cues common to both mother and littermates.
Settling nature and nurture into an ontogenetic niche
Authors: West Meredith J. , King Andrew P.
Published: January 2005

All organisms inherit parents' genes, but many also inherit parents, peers, and the places they inhabit as well. We suggest the term ontogenetic niche to signify the ecological and social legacies that accompany genes. A formal name is needed to give the idea of the inherited environment equal status with its conceptual cognates; nature and nurture. We argue here that increased recognition of the inherited environment facilitates unification efforts within the development sciences by emphasizing the affinity, rather than opposability, of ontogenetic processes.
Ontogeny of conditioned heart rate to an olfactory stimulus
Authors: Sananes Catherine B. , Gaddy James R. , Campbell Byron A.
Published: January 2005

When heart rate is used as the index of conditioning, rat pups younger than 15 days of age do not display an odor‐shock association. This constitutes a marked delay relative to the development of a somatomotor conditioned response. The incapacity to display autonomic learning to an olfactory stimulus prior to day 15 is not due to the inability to perceive and to orient to the olfactory stimuli used, nor to the inability to make unconditioned phasic cardiac changes. Rather, the late development of the heart rate conditioned response may indicate that the central neural mechanisms mediating heart rate conditioning are distinct from, and mature later than those mediating (1) heart rate orienting and (2) somatomotor conditioning. Evidence from studies in adult species is used to support these speculations.
Motor training and physical fitness: Possible short‐ and long‐term influences on the development of individual differences in behavior
Authors: Bekoff Marc
Published: January 2005

Individual differences in the behavior of young and adult animals have been documented in diverse species. Possible sources of such variation are of interest to scientists representing many disciplines, including behavior, genetics, and population and evolutionary biology. Two variables that may be important in the ontogeny and maintenance of behavioral differences are (1) individual physical (aerobic and anaerobic) fitness and (2) possible genetic variations underlying individual abilities to engage in, and to benefit from, motor training early in life. The differential development of aerobic and anaerobic capacities may play a significant role in the ontogeny of individual differences in the performance of various motor skills. There also may be short‐ and long‐term consequences of variations in physical fitness that influence individual abilities to perform energy demanding acts during aggressive encounters, interactions with prey or predators, and courtship and breeding. Genetic studies of a limited number of species indicate that specific genotypes are correlated with individual variations in motor performance, even among conspecifics. Multidisciplinary research concerning possible relationships among the ontogeny of physical fitness, genetics, and variations in behavior is needed. Recent work on the relationship between individual differences in physical fitness and variations in the behavior of adult cold‐blooded vertebrates provides a good model for comparative research on warm‐blooded species.
Artificial rearing of rat pups using rat milk
Authors: Moore Elizabeth , Stamper Colleen , Diaz Jaime , Murowchick Elise
Published: January 2005

The contribution of diet and surgery to the brain weight deficits observed in artificially reared rats was investigated. Four day old Long Evans rat pups were assigned to an artificially reared (AR) or mother reared (MR) group. AR pups were encannulated and fed either rat milk (AR‐MOM) or replacement formula (AR‐MES). MR. pups received a sham encannulation (MR‐SHAM) or no surgery (MR‐CONT) before being returned to their dam for rearing. On day 7 all the animals were killed. Brain weights and visceral organ weights were obtained. There was no significant difference between the MR groups on any measure except stomach weights. AR‐MOM pups had larger visceral organ weights than pups in the other groups. AR‐MOM and AR‐MES pups had similar whole brain weights, smaller than those of the MR pups. However, the cerebellar weights, and to a lesser extent, brainstem weights, showed improvements in the AR‐MOM group, over the AR‐MES group. Neither the effect of surgery nor of diet alone can account for the organ weight differences that have been described in AR rats. The possibility that normal growth may be primarily dependent on diet at one stage of development, with other factors gaining importance at later stages is discussed.
Differential rates of attack, defense, and counterattack during the developmental decrease in play fighting by male and female rats
Authors: Pellis Sergio M. , Pellis Vivien C.
Published: January 2005

During postweaning development, rats exhibit several well documented trends in their play fighting: (1) It peaks between 30–40 days and then declines with the approach of sexual maturity; (2) males initiate more play fights than females; and (3) the overall complexity of play fights, as expressed by such measures as duration of bouts, also decreases with increasing age. Such trends could arise from changes in attack or defense, or some combination of both. In this article it is shown that (a) the decline in play fighting with the onset of sexual maturity in rats results from a decline in attack, not in defense; (b) the differences in play fighting by male and female rats are due to sex‐specific rates of both attack and defense; (c) the developmental decrease in the complexity of play fighting arises from a decrease in the frequency of counterattacks (i.e., after an animal defends itself, it is less likely to launch an attack). In this way, age and sex differences in play fighting can be traced to differences in its subcomponents.
Weaning in rats: II. Pup behavior patterns
Authors: Thiels Edda , Alberts Jeffrey R. , Cramer Catherine P.
Published: January 2005

In this study, litters of rat pups and their mothers were continuously video‐monitored from Day 14 to Day 35 postpartum in order to describe the behavioral changes that occur during that period. Prior to the onset of solid food intake (Day 18), pups spent most of their active time suckling. During Days 18 to 26, feeding, drinking, grooming, and play‐fighting rapidly became frequent daily activities, while suckling gradually began to decline. By Day 28, pups' food and water intake relative to body weight and time allocated to the new behaviors reached asymptote. Pups nevertheless continued to suckle until Day 34. These results suggest that (1) the transition from milk to solid food is embedded in a multitude of behavioral changes; (2) these behavioral changes have distinct temporal characteristics; and (3) the developmental period between Days 14 and 34 can be divided into three phases.

Apart from the fascination and the self education of watching the developing of any form of life from its early protoplasmic simplicity into that complex maturity, there is solid scientific reason that Psychology has much to hope from minute and accurate records of the developmental periods of young animals of all species (Small, 1899).
Innate learning preferences: Signals for communication
Authors: Marler Peter
Published: January 2005

Research on the ways in which different species of birds learn to sing is used to illustrate the necessity of taking innate factors into account in studies of behavioral development. Experiments on two species of songbirds are described that reveal innate species differences in responsiveness to taperecorded songs. Conspecific songs are favored over those of other species. These patterns of innately varying responsiveness provide a basis for the development, not of stereotyped behavior, but of variable, individually learned behavior. The viewpoint is presented that mechanisms that differ innately from species to species, some with general functions, others specialized for particular ontogenetic assignments, provide the necessary substrates with which experience interacts.
Pre‐ and postweaning excretion of puberty‐influencing chemosignals in house mice
Authors: Drickamer Lee C.
Published: January 2005

Pre‐ and postweaning excretion urinary chemosignals that influence puberty in female house mice were tested. The dependent variable used to assess the effectiveness of urine samples collected from donor mice was the age of first vaginal estrus in young female mice. Preweaning excretion of the puberty‐delaying chemosignal by females was affected by litter sex composition; this effect interacted with the age of the young donor females. In litters of all females, the substance occurred from about the age of 9 days and in litters with 6 females and 2 males the delay substance was released from about the age of 17 days. Grouping dams during gestation but not prior to conception resulted in excretion of the puberty‐delaying substance in the female progeny from the age of 17 days or possibly earlier. Young male mice do not excrete the puberty‐accelerating chemosignal prior to the age of puberty. However, giving young males injections of testosterone resulted in an earlier first excretion of the acceleratory signal, suggesting that the machinery for chemosignal production is operative prior to the time of sexual maturity. Caging young males with an adult female prior to puberty resulted in earlier excretion of the puberty‐accelerating substance, while caging young males with adult males retarded excretion of the substance. The findings are discussed in terms of early hormone effects on behavior and with regard to consequences for the chemosignal systems in house mice. © 1992 Wiley & sons. Inc.
Contextual determinants of auditory learning in bobwhite quail embryos and hatchlings
Authors: Lickliter Robert , Hellewell Timothy B.
Published: January 2005

This study examined the ability of bobwhite quail embryos and hatchlings to learn an individual bobwhite maternal call. Results revealed that embryos could learn an individual maternal call and remember that call for at least 24 hr following exposure. In contrast, hatchlings reared socially in groups of same‐age chicks during postnatal exposure to a maternal call did not demonstrate a preference for that familiar call at 24 hr following exposure. However, individual auditory recognition was exhibited by hatchlings reared in social isolation, suggesting that the perceptual and social complexity of the postnatal situation can disrupt or interfere with early auditory learning. Additional support for this view was the finding that embryos exposed to unusually early visual stimulation during prenatal exposure to a maternal call also failed to prefer that familiar maternal call in subsequent choice tests. The idea that early auditory learning capacity is determined more by context and experience rather than the organism's specific age or stage of development is discussed. © 1992 Wiley & sons. Inc.
Intrauterine position effects on sexually dimorphic asymmetries of Mongolian gerbils: Testosterone, eye opening, and paw preference
Authors: Clark Mertice M. , Robertson Rohan K. , Galef Bennett G.
Published: January 2005

A series of experiments was undertaken to both discover and explore the causes of sexually dimorphic phenotypic asymmetries in infant and adult Mongolian gerbils. We found that (1) the order in which the eyes of individual gerbil pups opened varied with their gender; right eyes of female pups opened before left eyes, while left eyes of male pups opened before right eyes, and (2) the paw that adult gerbils held in the air while maintaining a species‐typical tripedal stance varied with gender; female gerbils held their right paws in the air significantly more often than did male gerbils. Both order of eye opening and laterality of paw use while in a tripedal stance varied significantly as a function of the intrauterine position which subjects had occupied as fetuses. These data implicate exposure to testosterone as a mediator of the development of asymmetries exhibited by Mongolian gerbils. © 1993 John Wiley & Sons, Inc.
The evaluator as educator
Authors: Wise Robert I.
Published: January 2005

Good evaluation shares much with good teaching. What makes an evaluation useful can depend on qualities of teaching brought to the evaluator's role.
Summary: Common themes and a checklist
Authors: Brown Robert D. , Braskamp Larry A.
Published: January 2005

Evaluators wishing to increase the utilization of their information can do so if they are willing to assume an active, planful, and ongoing role.
Can professional competence be measured?
Authors: Andrew Barbara J.
Published: January 2005

Assessment procedures can evaluate potential for competent practice, but cannot assure consistent and wise use of that potential.
Being ethical: Professional and personal decisions in program evaluation
Authors: Sieber Joan E.
Published: January 2005

Understanding how role conflicts arise in evaluation and deliberately planning to minimize them can lead to ethical program evaluation.
In search of standards
Authors: Baron Joan Boykoff , Baron Reuben M.
Published: January 2005

Born of a growing national demand for accountability, the field of evaluation has itself become increasingly suspect. Distinguishing between ethical standards and methodological guidelines may aid in the evaluation of evaluators.
The enigma of organizational effectiveness
Authors: Cameron Kim
Published: January 2005

Effectiveness is an elusive concept that can be approached through several models, none of which is appropriate in all circumstances.
Assessing performance‐based salary administration in the public sector
Authors: Bulgaro Patrick J. , Frucher Meyer S.
Published: January 2005

New York State's attempt to base salaries on performance illustrates the many problems that attend this type of employee appraisal system.
Comprehensive assessment of educational systems
Authors: Gormly John B.
Published: January 2005

Comprehensive assessment can lead to informed decision making in our schools. In the past, the focus of evaluation has been too narrow.
Toward guidelines for evaluating large‐scale computerized models
Authors: Thompson Bruce W.
Published: January 2005

To enable decision makers to become more aware of the levels of confidence that can be placed in the results of particular computerized decision models, means of establishing levels of confidence for such models are discussed.
Economic transformations of nonmonetary benefits in program evaluation
Authors: Nagel Stuart S.
Published: January 2005

The perennial problem of comparing apples to oranges finds hope for relief by assessing the preferences of decision makers and stakeholders in public policy decisions.
Using program information to plan evaluations
Authors: Holland Sherry
Published: January 2005

Information that describes a program's implementation and client audience can help the evaluator tailor the study to the constraints of particular settings and increase the likelihood that the evaluation can be implemented as planned.
Quasi‐experimental analysis: A mixture of methods and judgment
Authors: Cordray David S.
Published: January 2005

The role of human judgment in the development and synthesis of evidence has not been adequately developed or acknowledged within quasi‐experimental analysis. Like ordinary causal inference, comprehensive causal analysis requires not only consideration of plausible rival explanations but evidence that the purported causal agent is itself plausible.
Naturalistic evaluation
Authors: Guba Egon G.
Published: January 2005

Two forms of naturalistic evaluation have appeared in the literature within the past decade. One form treats this perspective as a collection of usually qualitative techniques that are complementary with conventional quantitative methods. The second form represents an alternative paradigm for evaluation. It emphasizes the negotiation of multiple socially‐constructed realities, interdependence of facts and values, and the emergent character of the evaluation process.
Examining racial discrimination with fair housing audits
Authors: Yinger John
Published: January 2005

Fair housing audits, an innovative quasi‐experimental technique, have made it possible to study the incidence and intensity of housing discrimination faced by minority families. Results from the application of this technique indicate that groups such as black, Hispanic, and Asian Americans face substantial discrimination in terms of the number, types, and location of housing units they are shown by realtors.
The use of self‐reports on sensitive behaviors in health program evaluation
Authors: D'Onofrio Carol N.
Published: January 2005

The use of sensitive self‐report data in the evaluation of contemporary health programs raises issues not addressed by textbooks.
Levels of analysis
Authors: Koepke David , Flay Brian R.
Published: January 2005

Considerations of purpose, feasibility, and statistical power, as well as internal, external, and construct validity, determine both the units of sample selection, randomization, treatment, and observation and the analytical model one uses.
Another view of program inspections by the Offices of Inspectors General
Authors: Sonnichsen Richard C.
Published: January 2005

The advent of program inspections by Offices of Inspectors General represents a departure from traditional evaluation practice. In the interest of advancing the evaluation profession, their approach deserves examination and debate by the non‐OlG evaluation community.
Synthesizing research in multicultural teacher education: Findings and issues for evaluation of cultural diversity
Authors: Beaudry Jeffrey S.
Published: January 2005

Issues for program evaluation are raised through an analysis of previous integrative research in multicultural teacher education.
Meeting the market for quality evaluation in education
Authors: Ginsburg Alan
Published: January 2005

Evaluation in the U.S. Department of Education declined significantly in the early 1980s. But a search for alternative management strategies and evaluation techniques has allowed the function to survive and prosper.
Evaluator training in a government setting
Authors: Kingsbury Nancy , Hedrick Terry E.
Published: January 2005

In 1988, the U.S. General Accounting Office started an ongoing, comprehensive evaluation training program for its staff. This chapter sketches the program and describes the major substantive areas of its curriculum.
Coexpression of glial fibrillary acidic protein and vimentin in the central and peripheral nervous systems of the twitcher mutant
Authors: Chiu F.‐C. , Sacchi R. S. , Claudio L. , Kobayashi S. , Suzuki K.
Published: January 2005

A method to purify glial fibrillary acidic protein (GFAP) from mouse spinal cord is described, which permits the measurement of GFAP in the sciatic nerve of the twitcher mutant and control mouse. Cytoskeletal proteins from sciatic nerves and purified GFAP standards were electrophoresed on gel, transferred to nitrocellulose paper, and immunostained with anti‐GFAP antibody. From the immunostained, 51,000‐dalton band, we estimated about 200 ng GFAP per 50 μg of cytoskeletal protein in the twitcher sciatic nerve. The control nerve showed no detectable GFAP. Double‐labeled fluorescence immunocytochemistry showed that in the brainstem of twitcer mutant, GFAP and vimentin were coexpressed in the majority of astrocytes.
Distribution of orthogonal arrays of particles in the Müller cell membrane of the mouse retina
Authors: Wolburg Hartwig , Berg Karin
Published: January 2005

In the present study we investigated the Müller cell membrane of the mouse retina by freeze‐fracturing. The mouse retina is vascularized and the vessels running outside the nerve fiber layer are completely encased by Müller cell endfeet. Orthogonal arrays of particles (OAP) reside in all membrane areas of the Müller cells. The paravitreous as well as the pericapillary endfeet reveal a considerably higher density of OAP than the nonendfoot membranes including the perikaryal ones. This is in contrast to the Müller cell membrane of the rabbit retina studied previously (Wolburg and Berg: Neurosci. Lett., 82:273–277, 1987). There we found a completely different distribution of OAP; practically all OAP reside in the endfoot membrane facing the vitreous body. The nonendfoot and perikaryal membranes were devoid of OAP. The OAP distribution in both species corresponds roughly to the distribution of the K+ conductances measured by Newman (J. Neurosci., 7:2423–2432, 1987). The putative relationship between OAP and K+ channels, including functional aspects, is discussed.