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Michael L Romero - One of the best experts on this subject based on the ideXlab platform.
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the effects of chronic psychological and physical stress on feather replacement in european starlings sturnus vulgaris
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2008Co-Authors: David E Strochlic, Michael L RomeroAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt, when all feathers are replaced. Recent evidence indicating that CORT implants slow the rate of feather regrowth in molting birds suggests that plasma CORT concentrations are downregulated during molt in order to avoid the inhibition of feather growth caused by the protein catabolic activity of CORT. To further test this hypothesis, we examined whether endogenous CORT release, stimulated by exposure to either psychological stress or physical stress (food restriction), could inhibit feather regrowth rates or decrease feather quality in birds undergoing an induced molt (feather replacement after plucking). European starlings (Sturnus vulgaris) were exposed to chronic psychological stress or food restriction for three weeks of the feather regrowth period. Throughout this time, the length of growing primary, secondary, and tail feathers was measured and blood samples were collected to measure baseline and stress-induced CORT concentrations. Upon completion of growth, feather quality was analyzed via measurements of mass, rachis length, feather area, and presence of fault bars. Both psychological and physical stress protocols elevated circulating plasma CORT but significantly less than implants from an earlier study did. Psychological stress had no effect on feather regrowth rates or feather quality. Food restriction had no effect on feather growth rate but caused asynchronous feather replacement. When combined with psychological stress, physical stress also resulted in smaller feather area. Results indicate that CORT implants may not accurately represent chronic stress physiology. Additionally, the purpose for downregulating CORT concentrations during molt appears to be more complicated than simply protecting feather production from CORT's catabolic effects.
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the effects of chronic psychological and physical stress on feather replacement in european starlings sturnus vulgaris
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2008Co-Authors: David E Strochlic, Michael L RomeroAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt, when all feathers are replaced. Recent evidence indicating that CORT implants slow the rate of feather regrowth in molting birds suggests that plasma CORT concentrations are downregulated during molt in order to avoid the inhibition of feather growth caused by the protein catabolic activity of CORT. To further test this hypothesis, we examined whether endogenous CORT release, stimulated by exposure to either psychological stress or physical stress (food restriction), could inhibit feather regrowth rates or decrease feather quality in birds undergoing an induced molt (feather replacement after plucking). European starlings (Sturnus vulgaris) were exposed to chronic psychological stress or food restriction for three weeks of the feather regrowth period. Throughout this time, the length of growing primary, secondary, and tail feathers was measured and blood samples were collected to measure baseline and stress-induced CORT concentrations. Upon completion of growth, feather quality was analyzed via measurements of mass, rachis length, feather area, and presence of fault bars. Both psychological and physical stress protocols elevated circulating plasma CORT but significantly less than implants from an earlier study did. Psychological stress had no effect on feather regrowth rates or feather quality. Food restriction had no effect on feather growth rate but caused asynchronous feather replacement. When combined with psychological stress, physical stress also resulted in smaller feather area. Results indicate that CORT implants may not accurately represent chronic stress physiology. Additionally, the purpose for downregulating CORT concentrations during molt appears to be more complicated than simply protecting feather production from CORT's catabolic effects.
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corticosterone inhibits feather growth potential mechanism explaining seasonal down regulation of corticosterone during molt
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2005Co-Authors: Michael L Romero, David E Strochlic, John C WingfieldAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt when all feathers are replaced. To explain why, we proposed that the birds downregulate natural CORT release during molt in order to avoid CORT's degradative effects on proteins and its inhibition of protein synthesis. If CORT exerted these effects during molt, it could slow protein deposition during feather production and potentially result in a longer period of degraded flight performance. To test this hypothesis, either empty or CORT-filled silastic implants were inserted into captive European starlings (Sturnus vulgaris) and white-crowned sparrows (Zonotrichia leucophrys) undergoing induced (feather replacement after plucking) and natural molts. We then measured the rate of feather re-growth by regularly measuring the length of primary, secondary, and tail feathers. CORT implanted birds showed a significantly decreased rate of feather growth compared to control animals. Basal CORT concentrations of induced molt and non-molting birds were also compared but no difference was noted. The results suggest a tradeoff; a complete set of new feathers may be more important to the survival of a bird than the ability of CORT to respond maximally to a stressor.
David E Strochlic - One of the best experts on this subject based on the ideXlab platform.
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the effects of chronic psychological and physical stress on feather replacement in european starlings sturnus vulgaris
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2008Co-Authors: David E Strochlic, Michael L RomeroAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt, when all feathers are replaced. Recent evidence indicating that CORT implants slow the rate of feather regrowth in molting birds suggests that plasma CORT concentrations are downregulated during molt in order to avoid the inhibition of feather growth caused by the protein catabolic activity of CORT. To further test this hypothesis, we examined whether endogenous CORT release, stimulated by exposure to either psychological stress or physical stress (food restriction), could inhibit feather regrowth rates or decrease feather quality in birds undergoing an induced molt (feather replacement after plucking). European starlings (Sturnus vulgaris) were exposed to chronic psychological stress or food restriction for three weeks of the feather regrowth period. Throughout this time, the length of growing primary, secondary, and tail feathers was measured and blood samples were collected to measure baseline and stress-induced CORT concentrations. Upon completion of growth, feather quality was analyzed via measurements of mass, rachis length, feather area, and presence of fault bars. Both psychological and physical stress protocols elevated circulating plasma CORT but significantly less than implants from an earlier study did. Psychological stress had no effect on feather regrowth rates or feather quality. Food restriction had no effect on feather growth rate but caused asynchronous feather replacement. When combined with psychological stress, physical stress also resulted in smaller feather area. Results indicate that CORT implants may not accurately represent chronic stress physiology. Additionally, the purpose for downregulating CORT concentrations during molt appears to be more complicated than simply protecting feather production from CORT's catabolic effects.
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the effects of chronic psychological and physical stress on feather replacement in european starlings sturnus vulgaris
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2008Co-Authors: David E Strochlic, Michael L RomeroAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt, when all feathers are replaced. Recent evidence indicating that CORT implants slow the rate of feather regrowth in molting birds suggests that plasma CORT concentrations are downregulated during molt in order to avoid the inhibition of feather growth caused by the protein catabolic activity of CORT. To further test this hypothesis, we examined whether endogenous CORT release, stimulated by exposure to either psychological stress or physical stress (food restriction), could inhibit feather regrowth rates or decrease feather quality in birds undergoing an induced molt (feather replacement after plucking). European starlings (Sturnus vulgaris) were exposed to chronic psychological stress or food restriction for three weeks of the feather regrowth period. Throughout this time, the length of growing primary, secondary, and tail feathers was measured and blood samples were collected to measure baseline and stress-induced CORT concentrations. Upon completion of growth, feather quality was analyzed via measurements of mass, rachis length, feather area, and presence of fault bars. Both psychological and physical stress protocols elevated circulating plasma CORT but significantly less than implants from an earlier study did. Psychological stress had no effect on feather regrowth rates or feather quality. Food restriction had no effect on feather growth rate but caused asynchronous feather replacement. When combined with psychological stress, physical stress also resulted in smaller feather area. Results indicate that CORT implants may not accurately represent chronic stress physiology. Additionally, the purpose for downregulating CORT concentrations during molt appears to be more complicated than simply protecting feather production from CORT's catabolic effects.
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corticosterone inhibits feather growth potential mechanism explaining seasonal down regulation of corticosterone during molt
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2005Co-Authors: Michael L Romero, David E Strochlic, John C WingfieldAbstract:Corticosterone (CORT) is seasonally modulated in many passerines, with plasma CORT concentrations lowest during the prebasic molt when all feathers are replaced. To explain why, we proposed that the birds downregulate natural CORT release during molt in order to avoid CORT's degradative effects on proteins and its inhibition of protein synthesis. If CORT exerted these effects during molt, it could slow protein deposition during feather production and potentially result in a longer period of degraded flight performance. To test this hypothesis, either empty or CORT-filled silastic implants were inserted into captive European starlings (Sturnus vulgaris) and white-crowned sparrows (Zonotrichia leucophrys) undergoing induced (feather replacement after plucking) and natural molts. We then measured the rate of feather re-growth by regularly measuring the length of primary, secondary, and tail feathers. CORT implanted birds showed a significantly decreased rate of feather growth compared to control animals. Basal CORT concentrations of induced molt and non-molting birds were also compared but no difference was noted. The results suggest a tradeoff; a complete set of new feathers may be more important to the survival of a bird than the ability of CORT to respond maximally to a stressor.
Sterck E.h.m. - One of the best experts on this subject based on the ideXlab platform.
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself.FSW – Publicaties zonder aanstelling Universiteit Leide
Roth T.s. - One of the best experts on this subject based on the ideXlab platform.
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself.FSW – Publicaties zonder aanstelling Universiteit Leide
Bionda T.r. - One of the best experts on this subject based on the ideXlab platform.
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself
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Duckling-catching by a zoo-housed western lowland gorilla (Gorilla gorilla gorilla)
2019Co-Authors: Roth T.s., Bionda T.r., Sterck E.h.m.Abstract:Surveys show that zoo-housed great apes occasionally interact with local wildlife. Bonobos and chimpanzees interact aggressively with and sometimes consume wildlife. Gorillas may also interact with local wildlife, but less often in an aggressive way and consumption was rare. Here we report the case of an adolescent female western lowland gorilla in Apenheul Primate Park (Apeldoorn, The Netherlands) that persistently catches and handles ducklings. Prior to observation we proposed four possible explanations, which are not mutually exclusive: play, meat eating, need for abnormal plucking, and allomothering. We saw the female catch ducklings at eight occasions (9 ducklings in total) and she handled ducklings (at least 19) on ten out of 17 observation days. Ad libitum observations showed that the female spent much time plucking the feathers of the duckling, handling it carefully. In addition, she regularly placed a duckling on her back during locomotion. Eating of a carcass was not observed and playing with a carcass was very rare. Based on these observations, we propose that not meat eating and play, but allomothering and abnormal plucking may explain this idiosyncratic behavior. This female probably invented the behavior herself.FSW – Publicaties zonder aanstelling Universiteit Leide
