ISSN:0012-1630    

DOI:10.1002/dev.420090502

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractMale offspring of prenatally stressed rats showed low levels of copulatory behavior during a series of brief tests with estrous females but successfully impregnated female cagemates during long term tests of breeding effectiveness. Sexual performance on the short term tests was inversely related to open field activity with the offspring of prenatally handled mothers exhibiting more sexual behavior and less open field activity. These results support the notion that prenatal stress influences both the sexual behavior and emotional reactivity of male offspring. Deficits observed during short term tests of breeding effectiveness appear to be reversible under optimal conditions.

ISSN:0012-1630    

DOI:10.1002/dev.420090503

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractIn 2 experiments, rats were given a mixture containing high doses of 1‐tri‐iodothyronine and 1‐thyroxine‐sodium on Day 4 after birth (Group T)Controls (C) received equivalent amounts of saline. During the preweaning period, half of the litters in the T and C groups were raised in an impoverished (I) condition, and half in an enriched (E) condition. Open‐field ambulation, rearing, defecation, and, in Experiment 2, grooming behavior were recorded during a 4‐day period at 210 days (Experiment 1) and at 90 days of age (Experiment 2). A consistent augmenting action of neonatal hormone stimulation on ambulation and rearing was found for both males and females. Hormone‐treated animals did not habituate their rate of general motor activity with repeated testings in the open‐field. An over‐all pattern of a larger effect of hormone‐treatment in the I condition than in the E condition was noted, particularly among the females. Thus, the experience of preweaning enrichment partly “normalized” the open‐field behavior of the T groups. The results are discussed in relation to an hypothesis concerning the interaction of rate of development of the central nervous system and environmental stimulation in d

ISSN:0012-1630    

DOI:10.1002/dev.420090504

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractThree‐week‐old pigs were subjected to dietary energy or protein restriction so as to prevent weight gain over a period of 8 weeks. During the last week of restriction their responses to a novel object introduced into an exploratory test situation were measured. The malnourished pigs exhibited indifference to the object, taking longer to make contact with it, spending less time playing with it, but not showing evidence of fear or avoidance of the object or the area in which it was located. Following 6 weeks of nutritional rehabilitation, the previously malnourished pigs again displayed less approach behavior to the novel object than controls, but the effect was substantially reduced. These observations are interpreted to support our hypothesis that a major mechanism through which early malnutrition produces long‐term effects on behavior is by disturbing those behaviors required for gathering information from the enviro

ISSN:0012-1630    

DOI:10.1002/dev.420090505

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractFemale Rockland‐Swiss albino mice were tested for aggression during 6 successive pregnancies and lactation periods or until they ceased to re‐mate. Fighting behavior was limited only to the lactation phase of each reproductive cycle. Although most animals exhibited fighting during every lactation period they completed, some exhibited fighting in some lactation periods but not in others. The intensity of aggression, as measured by the time spent fighting, was highest during the beginning of each lactation period and declined by the end of each period. Moreover, the intensity of aggression increased across the first 3 lactation periods and then declined on later lactation periods to a point below initial levels. Finally, the fighting behavior exhibited by multiparous animals was not due simply to previous fighting experience in that some multiparous mice exhibited postpartum aggression on the 6th lactation period in the absence of fighting experience during earlier lactation peri

ISSN:0012-1630    

DOI:10.1002/dev.420090506

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractNine‐day‐old S‐W mice receiving deep body hypothermia or hyperthermia immediately after escape training were retested 1 or 24 hr later. Results indicated that hypothermia impaired 24‐hr retention but had no effect upon 1‐hr memory. Hyperthermia had no effect, with the mice demonstrating retention of the escape response at both retest intervals. In Experiment 2, administration of hypothermia or hyperthermia 23 hr after original training had no effect upon memory nor did either treatment produce motoric deficits upon retest 1 hr following thermal exposure. Experiment 3 indicated that hypothermia administered immediately after training produced retention deficits directly related to amount of body temperature reduction following hypothermia. These data are similar to those obtained with adult mice and suggest that memory processess occurring in 9‐day‐old mice may represent the onset of functioning of processes underlying adult lon

ISSN:0012-1630    

DOI:10.1002/dev.420090507

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractHubbard cockerels, 1 day of age (n=91) were divided into 3 handling groups: (1) chicks from the 5‐Day group were removed from the brooder and isolated at 22°C for 3 min on each of the first 5 days; (2) chicks from the 15‐Day group received this treatment for 15 days; and (3) Control chicks were not handled. Within each group half were fed broiler starter for 5 weeks, and half were fed layer starter which produces slower growth. On Days 28, 35, 42, and 49 the average weight of 5‐Day birds was significantly higher than that of Controls; 15‐Day birds weighed slightly less than birds in the 5‐Day group. The weight advantage of the 5‐Day birds occurred with both starter rations, at all weighing periods, and did not appear to reflect increased food consumption. Similarities between these findings and results obtained with rodent

ISSN:0012-1630    

DOI:10.1002/dev.420090508

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractInfant rhesus monkeys whose mothers were fed diets providing 1, 2, or 4 g protein/kg body weight/day during pregnancy were tested on 13 behavioral tests during their first 60 days of life. (The diets had been shown to affect significantly the weights and blood protein concentrations of both pregnant and nonpregnant females)The tests sampled a wide range of behaviors, including visual and auditory perception, feeding reflexes, and locomotion. Despite the maternal dietary differences, the performances of infants on all tests were comparable in all groups. These data contrast with the finding of persistent deficit in rats born of protein‐deprived mother

ISSN:0012-1630    

DOI:10.1002/dev.420090509

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

摘要:

AbstractVisual evoked responses (VER's) were recorded from the cortex of immature Weddell seals, 3‐365 days of age. Results indicated a high degree of maturity at birth evident from the multiphasic array of waveforms and the comparatively short onset latency of the VER. At low flash intensities, single flashes evoked an immature secondary response. Topographical distribution of VER's were confined largely to the gyrus immediately adjacent to midline, from the posterior aspect near lambda to the vertex. Recordings from CI‐744 dosed seals displayed a well‐demarcated developmental sequence of VER's, contrary to VER's recorded in flaxedilized seals. Onset latency and waveform configuration changed concomitantly as a function of age. During the postnatal period from birth to weaning, VER changes were related to major behavioral events such as the seal's first encounter with swimming and diving at 2 weeks of age and weaning at 6 weeks o

ISSN:0012-1630    

DOI:10.1002/dev.420090510

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420090511

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1976

数据来源: WILEY