Social Reinstatement Behaviour Research Articles

Social preferences in Japanese quail chicks from lines selected for low or high social reinstatement motivation: effects of number and line identity of the stimulus birds

Divergent lines of Japanese quail which have been genetically selected over several generations for high (HSR) or low (LSR) levels of social reinstatement (SR) behaviour show corresponding differences in underlying social motivation (sociality). Because sociality is a particularly influential behavioural trait in precocial species, such selection may have important implications for poultry welfare and performance. However, we must first establish whether it might influence other important behavioural characteristics or capabilities, such as social discrimination. The present study compared the social preferences of LSR and HSR quail chicks for same- and different-line birds presented either singly or in small groups. Thus, the responses of individually tested chicks of both lines were compared in a two-choice runway test when the opposing goal boxes contained either 1 HSR vs. 1 LSR or 5 HSR vs. 5 LSR stimulus birds. More HSR quail moved first towards chicks of their own line than towards LSR ones, they approached HSR quail sooner and spent longer near them regardless of whether the stimulus birds were presented singly or in groups. Conversely, apart from moving towards same-line birds first when they were presented singly, LSR quail exhibited no social preferences. These findings provide clear evidence of line discrimination in HSR quail but it is not yet known if the responses of LSR birds reflected impaired discrimination, increased attention to the novel features of the test environment, or a simple lack of this particular social preference.

Place preferences of Japanese quail given a permanent choice between a social or a non-social but enriched situation

Japanese quail from two lines selected for high (HSR) or low (LSR) levels of social reinstatement behaviour were permanently placed from 2 days to 6 weeks of age in a situation where one tested animal had the choice between being in social contact with a stimulus animal in a bare compartment of the cage or out of visual contact with the stimulus animal in a relatively rich environment containing food, water and wood shavings. The young (1 or 2 weeks of age) quails spent most of their time (over 80%) in the social compartment, about 10% feeding and drinking, and about 10% performing other activities in the non-social compartment. Hardly any differences appeared between the two lines when 1 or 2 weeks old, but at 4 weeks of age the LSR quails started to decrease the time spent in the social compartment and this phenomenon only appeared at 6 weeks of age and to a lesser extent in the HSR quails. At 4 and 6 weeks the differences between lines were significant. The lack of difference between the two lines in young quails can be explained by the very high social motivation expressed even by LSR quails in the conditions of the study. When they are older line differences are expressed. This change coincides with the time when the natural coveys start to disperse and also with the beginning of sexual development. These results confirm the hypothesis of François et al. (François, N., Mills, A.D., Faure, J.M., 1997. Inter-individual distances in Japanese quail ( Coturnix japonica) selected for high or low levels of sociability. Behav. Process. (in press)) that line differences in social motivation persist into adult or near adult life and can still be demonstrated, provided the circumstances are such that aggression does not prevent close social contact.

Social discrimination in Japanese quail Coturnix japonica chicks genetically selected for low or high social reinstatement motivation

Japanese quail chicks of two lines genetically selected for low levels of social reinstatement behaviour (LSR) or high levels of social reinstatement behaviour (HSR) were housed in groups of three. The approach/avoidance tendencies of an individual chick from each group towards a familiar cagemate and a stranger from another group placed at opposite ends of a runway were measured at 7 days of age. Quail chicks of both genetic lines preferentially approached, spent longer near, and showed shorter mean distances from the cagemate than the stranger. Irrespective of stimulus type, the HSR quail generally showed shorter approach latencies, spent longer within 15 cm of the goal boxes, made more entries into these areas, and travelled further during the test than did their LSR counterparts. These findings demonstrated that Japanese quail chicks, of two genetic lines reared in small groups, successfully discriminated between familiar cagemates and strangers. They also suggest that there are no straightforward relationships between underlying social motivation and social preferences.

Species specificity of social reinstatement in Japanese quail Coturnix japonica genetically selected for high or low levels of social reinstatement behaviour

Divergent lines of Japanese quail Coturnix japonica showing high (HSR) or low (LSR) levels of social reinstatement (SR) behaviour (as measured in a treadmill apparatus) have been developed. However, it was not known if selection had influenced social reinstatement tendencies in a general or a species-specific fashion. Therefore, the present study compared the SR behaviour of quail chicks of the HSR and LSR lines and of a Control line when the goal box of the treadmill was empty or when it contained small, same-species groups of either Japanese quail, domestic fowl or Guinea fowl chicks. The results clearly demonstrated that the SR behaviour of Japanese quail chicks is species-specific and that this specificity has not been influenced during genetic selection, over sixteen generations, of the HSR and LSR lines. The HSR chicks showed more locomotor activity in the treadmill than did those of the other lines regardless of the nature of the goal-box stimulus. The results are discussed in terms of general activity, underlying fearfulness and social motivation.

Effects of CRF on isolated Japanese quails selected for fearfulness and for sociality

The effects of CRF on the behavior and plasma corticosterone levels of isolated Japanese quail chicks were determined. Doses of 15, 30, and 45 μg/kg of CRF reduced the number of distress vocalizations emitted during isolation in chicks of a control line. The behavioral responses to a 15 μg/kg dose of CRF in lines selected either for high (HSR) or low (LSR) level of sociality or for low (STI) or high (LTI) fearfulness were compared. CRF suppressed vocalizations and increased the number of pecks at food. In LTI and STI chicks, CRF decreased the number of distress calls. In HSR chicks, CRF increased the number of pecks at food and suppressed vocalizations. No effect of CRF was found in LSR chicks. Chicks of the HSR, LSR, LTI, STI, and control lines were injected with 15 μg/kg of CRF or saline solution and the level of corticosterone measured following a 15-min isolation period. CRF or isolation alone slightly activated the HPA axis, whereas CRF plus isolation greatly increased corticosterone levels except in the LSR line. These differential responses of LSR chicks and chicks of the other lines, indicate a possible role of CRF in the regulation of social reinstatement behavior.

Effects of test age, line and sex on tonic immobility responses and social reinstatement behaviour in Japanese quail Coturnix japonica

The tonic immobility (TI) response and social reinstatement (SR) behaviour (as assessed in a treadmill test) were measured in 1, 2, 4, 6 and 10 week old Japanese quail of lines selected for long (LTI) and short (STI) duration of TI weighted for independence from SR behaviour or high (HSR) and low (LSR) levels of SR behaviour weighted for independence from durations of TI. Irrespective of age, LTI line birds had the longest and STI line birds the shortest duration of TI. The duration of TI did not differ between the HSR and LSR lines. Levels of SR behaviour were always higher in HSR line birds than in birds of the LSR line. SR behaviour did differ significantly between the LTI and STI lines and was shown at levels intermediate between those of the HSR and LSR lines although pairwise comparisons of line differences were not necessarily significant. The age and sex of the birds did not influence the duration of TI but levels of SR behaviour were lower at 2 and 4 weeks than at other ages and males showed more SR behaviour than females.

Responses to isolation in Japanese quail genetically selected for high or low sociality

The adrenocortical, behavioral, and leucocytic responses to isolation, for 1, 3, or 72 h, of 7–10-day-old Japanese quail chicks, of lines selected for high (HSR) or low (LSR) levels of social reinstatement (SR) behavior, were studied. Isolation had no effect on plasma corticosterone levels of heterophil/lymphocyte measures in LSR line chicks. Conversely, circulating corticosterone levels were increased after 1 h of isolation in the HSR line, although they fell to control levels thereafter. Heterophil/lymphocyte ratios of HSR line chicks were also increased after 3 h of isolation but decreased to control levels thereafter. Isolated HSR line chicks were consistently more active and showed more peeping and jumping than LSR line chicks in which sitting and lying were more frequent. However, no such behavioral divergence was observed when HSR and LSR line chicks were housed in same-line groups. These results indicate that selection for SR behavior has influenced both underlying social motivation and responses to short-term isolation. Social separation appeared to be more stressful for HSR than LSR line chicks.

Divergent selection for duration of tonic immobility and social reinstatement behavior in Japanese quail (Coturnix coturnix japonica) chicks.

Japanese quail (Coturnix coturnix japonica) were selected over 8 generations for long or short duration of tonic immobility (TI) weighted for independence from social reinstatement (SR) behavior (as measured in a treadmill) and for high or low levels of SR behavior weighted for independence from duration of TI. Divergent selection for long or short duration of TI and for high or low levels of SR behavior resulted in immediate and significant responses that continued throughout the 8 generations. There was no evidence of a plateau in the response to selection in any of the lines. SR responses did not vary in lines selected for duration of TI and vice versa. Selection for short duration of TI led to in an increase in the number of inductions required to induce TI. Selection for low levels of SR behavior led to a decrease in the tendency to move toward conspecifics but not to an increase in the tendency to move away from conspecifics.

Divergent selection for duration of tonic immobility and social reinstatement behavior in Japanese quail (Coturnix coturnix japonica) chicks.

Divergent selection for duration of tonic immobility and social reinstatement behavior in Japanese quail (Coturnix coturnix japonica) chicks.