摘要:

AbstractPregnant guinea pigs were exposed to loom room noise at 115 dB A for 7.5 hr/day for various periods during the last one‐third of pregnancy. When the hearing of their offspring was tested by auditory brain stem‐evoked response techniques at 6‐dB intervals, peak IV latencies of exposed pups were found to be significantly longer than those of otherwise similar control pups. The latency differences corresponded to a 5‐dB increase in stimulus at medium stimulus levels and 10–12 dB near threshold. The results indicate that it is possible for noise‐induced hearing loss to occurin uteroin mammals whose auditory maturation process is complete, or nearly so, b

ISSN:0012-1630    

DOI:10.1002/dev.420150202

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

年代:1982

数据来源: WILEY

摘要:

AbstractEarly environmental enrichment was evaluated by its effect on the behavior of 7‐day‐old male and female domestic chicks in an open field or novel environment and in a hole‐in‐the‐wall test of timidity. The chicks were housed in same‐sex groups of 10. The bare environments contained wood litter, food, and water, whereas the enriched boxes also contained various objects. In the open field, immobility was lower while feeding, walking, jumping and vocalization were higher in the enriched birds than in those reared in the bare environment. Enrichment also decreased emergence latencies in the hole‐in‐the‐wall box. The increased stimulation provided by environmental enrichment may decrease fearfulness in subsequent fear‐inducing situations and may enhance the ability of animals

ISSN:0012-1630    

DOI:10.1002/dev.420150203

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

年代:1982

数据来源: WILEY

摘要:

AbstractThe reactions of 10‐day‐old great tit nestlings to 3 auditory stimuli were studied. The stimuli, presented on a series of feeding occasions, were (1) the species' “seeet” alarm call, (2) a song strophe of the great tit, and (3) a song strophe of the tree‐creeper (Certhia familiaris). In contrast to earlier findings in studies of older nestlings, these younger nestlings did not respond to the alarm call with cessation of begging. However, a significant differential effect of the alarm call was demonstrated when the conditioning rates for the nestlings' begging response to each of the 3 stimuli were determined. Thus, conditioning was significantly slower to the alarm call than to the other stimuli. The results agree with the general conception that responses to species‐specific calls develop gradually during early ontogenesis. Thus fear responses to the alarm call, such as cessation of begging and “freezing,” which are elicited in newly fledged young, are preceded by weaker aversive tendencies that are not obvious from observations of the nestlings' behavior in nature. It is suggested that the nestlings' exposure to contrasting auditory stimulation–their own begging call and the parental feeding call–constitutes the experiential base for withdrawal responses

ISSN:0012-1630    

DOI:10.1002/dev.420150204

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

年代:1982

数据来源: WILEY

摘要:

AbstractMongolian gerbils reared in standard laboratory cages and gerbils reared in cages containing a burrowlike shelter did not differ in their rate of development of escape responses to sudden visual stimulation. The presence of shelter in the rearing environment did, however, markedly slow the development of adult‐like patterns of exploration. Reduced exposure to illumination, experienced by shelter‐reared subjects, proved responsible for this retardation of development. The effect of shelter‐rearing on the development of exploratory behavior is interpreted as demonstrating an environmentally induced maintenance of an adaptive juvenile pattern of beh

ISSN:0012-1630    

DOI:10.1002/dev.420150205

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

年代:1982

数据来源: WILEY

摘要:

AbstractIn a 2‐choice situation, Mongolian gerbil pups show a preference for home‐cage bedding odor that appears during the 2nd postnatal week and is consistently high between Days 8 and 14. Pups show responses to certain nonanimal odors as early as Day 4, indicating that the motor capacity to orient to odors precedes the emergence of nest odor preference. Increases in pups' nest odor preference appear to parallel increases in the frequency of maternal nest‐building, an activity which can eject pups from the nest. This coincidence suggests that olfaction helps displaced pups to return to their

ISSN:0012-1630    

DOI:10.1002/dev.420150206

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

年代:1982

数据来源: WILEY

摘要:

AbstractAn experimental method for blocking maternal lactation is reviewed and the possible application of this technique for experimentally manipulating weaning is considered. Maternal milk production can be inhibited using the prolactin‐suppressing drug bromocriptine. The suitability of bromocriptine for use in behavioral experiments is considered. The pharmacology of bromocriptine (CB 154) is briefly outlined and a compilation of the reported lactation‐inhibiting doses for various species is presented. The possible endocrine and behavioral side‐effects and the toxicity of the drug are discussed. It is concluded that, in most species studied so far, the drug is relatively free from significant side‐effects at the low doses needed to suppress lactation. Guidelines for the practical use of bromocriptine are suggested. Finally, some ideas about the possible applications of the drug to the study of behavioral development and parent–offspring relationships are

ISSN:0012-1630    

DOI:10.1002/dev.420150207

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

年代:1982

数据来源: WILEY

摘要:

AbstractIn 2 experiments the performance of 90‐ and 150‐day‐old light‐reared and dark‐reared rats was compared under appetitive reinforcement conditions on rigorous tests of form discriminative abilities. Although early stimulatory history had little impact on either the ability to discriminate shapes on the basis of contour orientation or to generalize from that initial experience to lines in other orientations, lack of visual experience did have significant consequences with respect to a comparable task in which the relationship between lines was the significant feature. Little change in the initial deficits was observed with exposure to a normal light environment for 60 days following the period of early visual deprivation in the case of this 2nd complex pattern discrimina

ISSN:0012-1630    

DOI:10.1002/dev.420150208

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

年代:1982

数据来源: WILEY

摘要:

AbstractFor a portion of their ontogeny, the juveniles of many mammalian species appear resistant to aggressive attack by adult male conspecifics. The possibility that urinary odors and small size contribute to this immunity from attack was investigated with C57/Bl, A/J, and DW/J laboratory mice. The results of the 1st of 6 experiments were that juvenile mice of both genders evoked great curiosity from aggressive resident male adults, but juveniles were rarely attacked. In Experiments II and III, exchanging urine between juveniles and adult males suggested that juveniles possess a distinctive odor. In Experiments IV–VI, dwarf adults, normal‐sized adults, and juveniles were placed with aggressive adult male residents. The dwarf males were attacked, but not as severely as normal‐sized male intruders (Experiment IV). The dwarf males, however, evoked more aggressive behavior than juveniles (Experiment V), and juveniles with the odors from either normal‐sizedordwarf adult males were attacked more readily than non‐odorized juveniles (Experiment VI). These data suggest that both odor and size contribute to the juveniles' immunity fr

ISSN:0012-1630    

DOI:10.1002/dev.420150209

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

年代:1982

数据来源: WILEY

ISSN:0012-1630    

DOI:10.1002/dev.420150201

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

年代:1982

数据来源: WILEY