Runway tests are considered indicative of underlying sociality in birds and their ability to make... more Runway tests are considered indicative of underlying sociality in birds and their ability to make social discriminations and establish interactions among conspecifics. Herein, social reinstatement behavior in male juvenile Japanese quail selected for a reduced (LS, low stress) or exaggerated (HS, high stress) adrenocortical response to brief mechanical restraint was evaluated. Individual males were given the choice to reinstate with either 2 (low density, LD) or 8 (high density, HD) unfamiliar randombred conspecifics placed in goal boxes at opposite ends of a two-choice runway (TCRW). Then, the same males were individually retested in a single goal box runway wherein they were exposed to a goal box containing either a LD or a HD of males. In the TCRW, a higher (P < 0.01) number of HS males started their ambulation toward the goal box containing the HD as opposed to LD of conspecifics. The HS males also spent more (P < 0.01) time in close proximity (within a 10-cm close zone; CZ) to the HD (218 s) rather than LD (57 s) of conspecifics. In contrast, the LS males did not differ in their initial direction of travel and they spent similar average amounts of times in the CZ of their stimulus LD (141 s) and HD (124 s) conspecifics. Similar to the TCRW results, in the single goal box runway, HS males spent more (P < 0.01) time in the CZ of HD rather than LD conspecifics, whereas LS quail spent similar amounts of time in the CZ of LD and HD males. Considering that runways are novel (and therefore frightening) environments, our findings suggest that HS quail may find better shelter (i.e., more comfort) in close proximity to a larger rather than smaller group of conspecifics, whereas LS birds find groups of varying conspecific density equally attractive. The results suggest that LS quail possess favorable social adaptive qualities because they appear to be better suited to cope with situations where the density of conspecifics is variable.
1. This study examines the time courses of male mating behaviours using quail that were categoris... more 1. This study examines the time courses of male mating behaviours using quail that were categorised at 2 d of age as high performance (HP) or low performance (LP) individuals in a T-maze.2. Individually caged males from each T-maze category were observed for 5 min after a female of the same category (HP or LP) was introduced into their home cages as a sexual partner at 4, 5, 6, 8, 10 and 12 weeks of age. The number of grabs, mounts and cloacal contacts performed by each male and his copulatory efficiency (number of cloacal contacts/number of grabs; CE) were determined at each time interval.3. No differences were observed in the proportion of HP and LP males performing grabs at any of the ages evaluated. However, a greater proportion of HP males showed mounting and cloacal contact behaviour, coupled with a higher CE than did their LP counterparts at 5 and 6, 6 and 8, and 8 weeks of age, respectively. At those ages, a higher mean number of mounts and cloacal contacts were also observed. No significant sexual behaviour differences between HP and LP quail were observed at 10 and 12 weeks of age.4. The results suggest that rapid negotiation of the T-maze in hatchlings is associated with accelerated puberty in male quail. The differential reproductive behaviour of HP males during the development of puberty does not remain extant in fully developed quail.5. The finding of accelerated male developmental sexual activity responses in HP quail indicates that selection for T-maze HP behaviour may allow males to be successfully bred at an earlier age.
The present study evaluates the organization and complexity of the temporal pattern of locomotion... more The present study evaluates the organization and complexity of the temporal pattern of locomotion after an acute administration of propofol in Japanese quail by using traditional and fractal analysis. Birds were administered with propofol 0, 10, 20, 40 or 80 mg/kg. Ten min after administration, they were placed in an open-field apparatus and their locomotor activity was recorded during 45 min at a resolution of 0.5 s. A significant dose dependant increase in the latency to initiate ambulation was observed for doses of 20, 40 and 80 mg/kg when compared to the control group. A rapid recuperation of normal locomotor activity was observed after sedation with 20 mg/kg. Birds administered with propofol 40 mg/kg showed signs of recuperation of normal locomotion after 30 and 40 min (males and females, respectively) of propofol administration, that was not observed in quail treated with propofol 80 mg/kg. Our results suggest that depending on the dose, propofol administration in quail may allow full locomotor recovery of a sedative/anesthetic dose as early as 30 min post-administration.
Genetic selection for appropriate levels of sociality (motivation to be with conspecifics) could ... more Genetic selection for appropriate levels of sociality (motivation to be with conspecifics) could benefit poultry welfare and performance. Runway tests that require chicks to traverse a corridor in order to reach other chicks in a goal box are commonly used to measure this behavioural trait. However, we need to determine if the chicks' responses in such tests are sensitive to certain experiential variables before we can recommend possible selection criteria for future breeding programmes. The present study focused on fear and on the identity of the stimulus birds. Broiler chicks either remained undisturbed or were exposed to an acute stressor (mechanical restraint) before their tonic immobility fear responses were measured 1h later in Experiment 1. Exposure to the stressor significantly prolonged tonic immobility and, hence, presumably, underlying fear levels. In Experiment 2, the responses of stressed chicks and undisturbed controls were assessed when they were tested individually in a runway with a goal box containing either familiar or unfamiliar chicks of the same age. Our finding that stressed chicks emerged from the start box sooner and spent longer near the stimulus birds suggests that exposure to a frightening event increased social reinstatement motivation. Furthermore, social affiliation was more pronounced when the goal box contained familiar cagemates rather than strange chicks, regardless of prior treatment. This finding demonstrates that broiler chicks that were housed in groups of twelve can discriminate between familiar and unfamiliar conspecifics encountered in novel surroundings. Thus, sociality was positively associated with fearfulness and broilers clearly showed social discrimination in runway tests. These findings highlight the dangers of disregarding variables, such as fear and the capacity for social recognition in tests of social motivation. We strongly recommend that exposure to frightening events prior to test should be avoided and that the identity of the birds in the runway goal box should be standardized, i.e. either familiar or unfamiliar, and noted.
Runway tests are considered indicative of underlying sociality in birds and their ability to make... more Runway tests are considered indicative of underlying sociality in birds and their ability to make social discriminations. We evaluated whether experience of a prior stressor alters the subsequent affiliation responses of 9 or 10-day-old chicks simultaneously exposed to familiar (cagemates) and unfamiliar conspecifics placed in goal boxes at opposite ends of a runway. Birds were housed in groups of eight in home cages. Half of the birds in each home cage were used as either familiar or unfamiliar social stimuli in the goal boxes. The other half of the birds were randomly assigned either to a control (CON; n = 51) group that remained undisturbed until testing or to a stress-treatment (STR; n = 52) group that was exposed to a 5min restraint stressor, returned to its home cage and then tested 1 h later. Birds were individually tested in the runway for 5 min and the behaviours video-recorded. During revision of tapes, the projected floor image of the runway was divided into squares and zones. The stressor decreased (P < 0.01) the time spent in close proximity (close zone; CZ) to conspecifics regardless of the familiarity of the stimulus birds. Regardless of treatment, test chicks showed shorter latencies to enter (P < 0.05) and spent longer time (P < 0.02) in the familiar than in the unfamiliar CZ suggesting that young chicks can discriminate between familiar and unfamiliar conspecifics encountered in novel surroundings. While in close proximity to familiar conspecifics, STR birds showed a reduced (P < 0.05) number of squares entered compared to CONs. This reduced locomotor activity was not accompanied by an increased activity in other zones of the runway. At the end of the trial, both CON and STR birds showed a reduced (P < 0.05) locomotor activity in the unfamiliar CZ and an increased (P < 0.05) activity in the central zone of the runway. Interestingly, no differences were detected between CON and STR birds in the total number of squares entered during the trial. These results suggest that prior stressor exposure did not affect the overall amount of locomotion but altered the spatial distribution of it. Collectively, our findings suggest that exposure to an acute stressor event subsequently affects chicks' affiliation responses in runway tests. The way a bird will react depends on the identity (familiar or unfamiliar) of the conspecifics in its close environment. #
Velázquez pinta en 1657 para D. Pedro de Arce, Montero del Rey (persona destinada para la servidu... more Velázquez pinta en 1657 para D. Pedro de Arce, Montero del Rey (persona destinada para la servidumbre del Rey, en el monte) la obra "Las hilanderas" compuesta por cinco mujeres que preparan las lanas para la fabricación de tapices: En la zona de la izquierda
Runway tests are considered indicative of underlying sociality in birds and their ability to make... more Runway tests are considered indicative of underlying sociality in birds and their ability to make social discriminations and establish interactions among conspecifics. Herein, social reinstatement behavior in male juvenile Japanese quail selected for a reduced (LS, low stress) or exaggerated (HS, high stress) adrenocortical response to brief mechanical restraint was evaluated. Individual males were given the choice to reinstate with either 2 (low density, LD) or 8 (high density, HD) unfamiliar randombred conspecifics placed in goal boxes at opposite ends of a two-choice runway (TCRW). Then, the same males were individually retested in a single goal box runway wherein they were exposed to a goal box containing either a LD or a HD of males. In the TCRW, a higher (P &amp;amp;lt; 0.01) number of HS males started their ambulation toward the goal box containing the HD as opposed to LD of conspecifics. The HS males also spent more (P &amp;amp;lt; 0.01) time in close proximity (within a 10-cm close zone; CZ) to the HD (218 s) rather than LD (57 s) of conspecifics. In contrast, the LS males did not differ in their initial direction of travel and they spent similar average amounts of times in the CZ of their stimulus LD (141 s) and HD (124 s) conspecifics. Similar to the TCRW results, in the single goal box runway, HS males spent more (P &amp;amp;lt; 0.01) time in the CZ of HD rather than LD conspecifics, whereas LS quail spent similar amounts of time in the CZ of LD and HD males. Considering that runways are novel (and therefore frightening) environments, our findings suggest that HS quail may find better shelter (i.e., more comfort) in close proximity to a larger rather than smaller group of conspecifics, whereas LS birds find groups of varying conspecific density equally attractive. The results suggest that LS quail possess favorable social adaptive qualities because they appear to be better suited to cope with situations where the density of conspecifics is variable.
1. This study examines the time courses of male mating behaviours using quail that were categoris... more 1. This study examines the time courses of male mating behaviours using quail that were categorised at 2 d of age as high performance (HP) or low performance (LP) individuals in a T-maze.2. Individually caged males from each T-maze category were observed for 5 min after a female of the same category (HP or LP) was introduced into their home cages as a sexual partner at 4, 5, 6, 8, 10 and 12 weeks of age. The number of grabs, mounts and cloacal contacts performed by each male and his copulatory efficiency (number of cloacal contacts/number of grabs; CE) were determined at each time interval.3. No differences were observed in the proportion of HP and LP males performing grabs at any of the ages evaluated. However, a greater proportion of HP males showed mounting and cloacal contact behaviour, coupled with a higher CE than did their LP counterparts at 5 and 6, 6 and 8, and 8 weeks of age, respectively. At those ages, a higher mean number of mounts and cloacal contacts were also observed. No significant sexual behaviour differences between HP and LP quail were observed at 10 and 12 weeks of age.4. The results suggest that rapid negotiation of the T-maze in hatchlings is associated with accelerated puberty in male quail. The differential reproductive behaviour of HP males during the development of puberty does not remain extant in fully developed quail.5. The finding of accelerated male developmental sexual activity responses in HP quail indicates that selection for T-maze HP behaviour may allow males to be successfully bred at an earlier age.
The present study evaluates the organization and complexity of the temporal pattern of locomotion... more The present study evaluates the organization and complexity of the temporal pattern of locomotion after an acute administration of propofol in Japanese quail by using traditional and fractal analysis. Birds were administered with propofol 0, 10, 20, 40 or 80 mg/kg. Ten min after administration, they were placed in an open-field apparatus and their locomotor activity was recorded during 45 min at a resolution of 0.5 s. A significant dose dependant increase in the latency to initiate ambulation was observed for doses of 20, 40 and 80 mg/kg when compared to the control group. A rapid recuperation of normal locomotor activity was observed after sedation with 20 mg/kg. Birds administered with propofol 40 mg/kg showed signs of recuperation of normal locomotion after 30 and 40 min (males and females, respectively) of propofol administration, that was not observed in quail treated with propofol 80 mg/kg. Our results suggest that depending on the dose, propofol administration in quail may allow full locomotor recovery of a sedative/anesthetic dose as early as 30 min post-administration.
Genetic selection for appropriate levels of sociality (motivation to be with conspecifics) could ... more Genetic selection for appropriate levels of sociality (motivation to be with conspecifics) could benefit poultry welfare and performance. Runway tests that require chicks to traverse a corridor in order to reach other chicks in a goal box are commonly used to measure this behavioural trait. However, we need to determine if the chicks&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39; responses in such tests are sensitive to certain experiential variables before we can recommend possible selection criteria for future breeding programmes. The present study focused on fear and on the identity of the stimulus birds. Broiler chicks either remained undisturbed or were exposed to an acute stressor (mechanical restraint) before their tonic immobility fear responses were measured 1h later in Experiment 1. Exposure to the stressor significantly prolonged tonic immobility and, hence, presumably, underlying fear levels. In Experiment 2, the responses of stressed chicks and undisturbed controls were assessed when they were tested individually in a runway with a goal box containing either familiar or unfamiliar chicks of the same age. Our finding that stressed chicks emerged from the start box sooner and spent longer near the stimulus birds suggests that exposure to a frightening event increased social reinstatement motivation. Furthermore, social affiliation was more pronounced when the goal box contained familiar cagemates rather than strange chicks, regardless of prior treatment. This finding demonstrates that broiler chicks that were housed in groups of twelve can discriminate between familiar and unfamiliar conspecifics encountered in novel surroundings. Thus, sociality was positively associated with fearfulness and broilers clearly showed social discrimination in runway tests. These findings highlight the dangers of disregarding variables, such as fear and the capacity for social recognition in tests of social motivation. We strongly recommend that exposure to frightening events prior to test should be avoided and that the identity of the birds in the runway goal box should be standardized, i.e. either familiar or unfamiliar, and noted.
Runway tests are considered indicative of underlying sociality in birds and their ability to make... more Runway tests are considered indicative of underlying sociality in birds and their ability to make social discriminations. We evaluated whether experience of a prior stressor alters the subsequent affiliation responses of 9 or 10-day-old chicks simultaneously exposed to familiar (cagemates) and unfamiliar conspecifics placed in goal boxes at opposite ends of a runway. Birds were housed in groups of eight in home cages. Half of the birds in each home cage were used as either familiar or unfamiliar social stimuli in the goal boxes. The other half of the birds were randomly assigned either to a control (CON; n = 51) group that remained undisturbed until testing or to a stress-treatment (STR; n = 52) group that was exposed to a 5min restraint stressor, returned to its home cage and then tested 1 h later. Birds were individually tested in the runway for 5 min and the behaviours video-recorded. During revision of tapes, the projected floor image of the runway was divided into squares and zones. The stressor decreased (P < 0.01) the time spent in close proximity (close zone; CZ) to conspecifics regardless of the familiarity of the stimulus birds. Regardless of treatment, test chicks showed shorter latencies to enter (P < 0.05) and spent longer time (P < 0.02) in the familiar than in the unfamiliar CZ suggesting that young chicks can discriminate between familiar and unfamiliar conspecifics encountered in novel surroundings. While in close proximity to familiar conspecifics, STR birds showed a reduced (P < 0.05) number of squares entered compared to CONs. This reduced locomotor activity was not accompanied by an increased activity in other zones of the runway. At the end of the trial, both CON and STR birds showed a reduced (P < 0.05) locomotor activity in the unfamiliar CZ and an increased (P < 0.05) activity in the central zone of the runway. Interestingly, no differences were detected between CON and STR birds in the total number of squares entered during the trial. These results suggest that prior stressor exposure did not affect the overall amount of locomotion but altered the spatial distribution of it. Collectively, our findings suggest that exposure to an acute stressor event subsequently affects chicks' affiliation responses in runway tests. The way a bird will react depends on the identity (familiar or unfamiliar) of the conspecifics in its close environment. #
Velázquez pinta en 1657 para D. Pedro de Arce, Montero del Rey (persona destinada para la servidu... more Velázquez pinta en 1657 para D. Pedro de Arce, Montero del Rey (persona destinada para la servidumbre del Rey, en el monte) la obra "Las hilanderas" compuesta por cinco mujeres que preparan las lanas para la fabricación de tapices: En la zona de la izquierda
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