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Observations on the Effects of Music Exposure to Growing Performance of Meat-Type Chicks
Research Notes OBSERVATIONS ON THE EFFECTS OF MUSIC EXPOSURE TO GROWING PERFORMANCE OF MEAT-TYPE CHICKS A. C. CHRISTENSEN AND A. D. KNIGHT
Animal Science Department,
California State Polytechnic University, Pomona, California 91768 (Received for publication September 23, 1974)
POULTRY SCIENCE 54: 619-621, 1975
INTRODUCTION
S
OUND, as an environmental quality factor, has attracted considerable attention in recent years. Results of research inquiry suggest that environmental sounds can cause significant changes in physiological function, the nature of the response varying with the quality, quantity and combination of sounds present (Brown and Glick, 1971). The compilation edited by Welch and Welch (1970) contains much of the published information which is currently available treating the effects of sounds upon biological organisms. Most of these compiled reports consider sound as a stress factor and observe the adverse effects on farm animals and other species exposed to sonic booms, freeway noises and other industrial sounds. Other reported research indicates that control of sound can be used with beneficial effects. It is generally recognized that different vocalizations of birds transmit meaningful information to other birds (Fringes and lumber, 1954; Lanyon and Tavolga, 1960). Jackson (1970) recorded what he termed "happy" singing sounds of hens on nest and played them back to hysteria prone flocks and succeeded in reducing the incidence of flock
hysteria. Popular publications have contained reports that music can be used to increase production of dairy cows, and recent studies indicate that swine may also respond in a favorable manner (Breeden, 1972). If quantitative and qualitative differences in sounds can be discerned by livestock species, then control of such sounds might profitably be used to enhance production. This study was conducted to evaluate the effects of two types of music played at two levels of intensity upon the growth rate and performance of broiler chickens. MATERIALS AND METHODS One hundred eight-day old H and N meat chicks were individually identified then allotted randomly into five groups of 20 chicks. Each group was housed in a cage 120 by 230 centimeters with a wire floor 90 centimeters above the ground and a tin room 70 centimeters above the floor. The cages were spaced 90 centimeters apart with baled hay stacked between them to serve as a sound barrier. The hay bales extended approximately one meter above and three meters beyond the walls of each cage. Though the bales were unpretentious in appearance, they 619
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
ABSTRACT One hundred eight-day old meat type chicks were randomly allotted into a control group and four music exposure treatment groups as follows: high level dinner music, low level dinner music, low level rock and roll music, and high level rock and roll music. Low level music reached a maximum decibel reading of 70 and high level music a maximum reading of 85. Feed consumption by group and individual weights were determined weekly during a nine-week feeding period. Feed consumption by groups was very similar and did not indicate any apparent tranquilizing effect or stress associated with treatments. Final live weight and carcass weight of the high level rock and roll group were somewhat less heavy than the others with the difference between low level dinner (1491 g.) and high level rock and roll (1398 g.) approaching statistical significance (P < .1).
620
RESEARCH NOTES
mined. One bird was eliminated from group 3 during the third week after a leg was accidentally broken during weighing. Group 4 was also reduced to 19 birds by a death loss during the eighth week. Weight data were analyzed by the method of fitting constants in a two-factor table and analysis of variance (Snedecor, 1956). Sex adjusted averages were compared to evaluate the treatment effects. RESULTS AND DISCUSSION Birds in each of the four music treatment groups were frightened by their initial exposure to music. Most of the birds in each cage piled up in the corners farthest from the speakers. Others laid flat on the floor with their necks outstretched and their eyes closed. This reaction gradually decreased through the first week and was not observed after that time. Thereafter, the birds distributed evenly throughout the cage with no apparent reluctance to stand directly in front of the speakers. By the end of the second week, birds in each of the groups exposed to music had started to intermittently twitch their heads in a jerking motion. This behavior continued through the rest of the experiment. Twitching was also observed among the control group, but only infrequently. If a manifestation of nervousness, it was apparently not reflected in differences in feed consumption. The cumulative feed consumed by each of the five groups during the study was very similar. Expressed as total feed per bird, consumption values averaged 4980, 5244, 4958, 5071 and 5144 grams for groups 1 through 5, respectively. (Table 1). Final weights are given in Table 1. Weights of the controls, low level dinner and low level rock and roll groups (2019, 2044 and 2031 grams, respectively) were intermediate to the high level dinner (2053 g.) and the high level rock and roll (1914 g.) groups. Though the 112 gram difference between the latter two groups was not statistically significant (P >
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
did provide an effective sound barrier between treatment groups. Cages housing groups 2, 3, 4 and 5 were each equipped with an 8-inch speaker placed at one end of the cage. Music was tape recorded and played continuously for 12 hours each day between 8:00 a.m. and 8:00 p.m. This time period corresponded to most of the daylight hours when the chicks were awake and active. Due to the nature of the physical facilities, no artificial light was provided. All sound levels were periodically monitored on the B scale of a General Radio Sound Level Meter placed in the middle of the cage floor. Group 1 (control) received an ambient noise level of about 60 db., which consisted primarily of chicken noises. Groups 2, 3, 4 and 5 received music treatments designated as follows: (2) high level dinner music; (3) low level dinner music; (4) low level rock and roll music; and (5) high level rock and roll music. The same dinner music was played to groups 2 and 3 and the same rock and roll music to groups 4 and 5, with sound levels regulated by a volume control. Low levels for each type music were regulated so that louder tones registered a maximum of 70 db. Louder tones of the high level groups registered a maximum of 85 db. Hou and Blaine (1971) observed that the hearing range of the chicken is somewhat comparable to that of humans. Prolonged exposure to sound levels of 80 db. is close to, but below that generally believed to cause permanent hearing impairment (Davis, 1970). A slightly higher level was adopted for this study as a level which might be associated with stress as reflected in rate and efficiency of gain. Feed was supplied on an ad libitum basis and consumption calculated weekly for each group. Birds were individually weighed weekly through a 9-week feeding period. At the time of slaughter, final live weights and dressed warm carcass weights were deter-
621
RESEARCH NOTES
TABLE 1.—Treatment means for feed consumption, live weight, warm dressed carcass weight and percent yield Feed consumption Carcass Live per % Yield weight (g.) weight (g.) Treatment' bird (g.) 1 72.3 1461 2020 4980 72.0 1480 2053 5244 2 72.9 1491 2045 4958 3 73.1 1486 2032 5071 4 72.0 1398 1942 5144 5 'Treatment groups: 1 = Control; 2 = high level dinner music; 3 = low level dinner music; 4 low level rock and roll music; 5 = high level rock and roll music. enhance production over the absence of music or whether loud rock and roll music causes stress and a resultant reduction in performance. REFERENCES Breeden, L., 1972. Effect of music on hog production. Hog Farm Management, 9 (11): 16. Brown, W. H., and B. Glick, 1971. Selected physiological responses of chickens. Amer. Soc. Agr. Eng. 14: 508-510. Christensen, A. C , and R. L. Nelson, 1971. Unpublished data. California State Polytechnic University, Pomona, California. Davis, H., and S. R. Silverman, 1970. Hearing and Deafness. Third Ed. Holt, Rinehart and Winston, New York. Fringes, H., and J. Jumber, 1954. Preliminary studies on the use of specific sounds to repel starlings from objectionable roosts. Science, 119: 318-319. Hou, Su-Ming, and M. A. Boone, 1971. The audibility curve of the chicken. Poultry Sci. 50: 1586. Jackson, D., 1970. Sound therapy for avian hysteria. Poultry Digest, 29: 286-287. Lanyon, W. E., and W. N. Tavolga, 1960. Animal Sounds and Communications. American Institute of Biological Sciences, Pub. No. 7, Washington. Snedecor, G. W., 1956. Statistical Methods. Iowa State University Press, Ames, Iowa. Welch, B. L., and A. S. Welch, 1970. Physiological Effects of Noise. Plenum Press, New York.
APRIL 10, 1975. DISTILLERS FEED CONFERENCE, GALT HOUSE, LOUISVILLE,
KENTUCKY
APRIL 30, MAY 1-2, 1975. FACT FINDING CONFERENCE, POULTRY AND EGG INSTITUTE OF AMERICA, NEW ORLEANS, LOUISIANA JULY 28-30, 1975. 67th ANNUAL MEETING OF THE AMERICAN SOCIETY OF ANIMAL SCIENCE, COLORADO STATE UNIVERSITY, FORT COLLINS, COLORADO
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
.1), these results were of the same magnitude as those obtained in a preliminary study (Christensen and Nelson, 1971) contrasting dinner music with rock and roll music, both played at approximately 85 to 90 db. Average dressed carcass weights (Table 1) differed slightly from the live weights in order, group 3 being heaviest at 1491 g. and group 5 lightest at 1398 g. (P < .1). This difference in order of groups from live to dressed weights is reflected in slight differences in yield (Table 1). However, there is no indication of any relationship between yield and music treatment to which the various groups were subjected. Heart and liver weights and gross examination of other organs was made on all birds. No abnormalities were found and no differences observed which could be ascribed to treatment effects. Though the results of this study are inconclusive, they do suggest some perception by the chick, which is reflected in a change in growth performance, to loud levels of contrasting types of music. Further study would have to be undertaken to demonstrate whether dinner type music can be used to
Animal Science Department,
California State Polytechnic University, Pomona, California 91768 (Received for publication September 23, 1974)
POULTRY SCIENCE 54: 619-621, 1975
INTRODUCTION
S
OUND, as an environmental quality factor, has attracted considerable attention in recent years. Results of research inquiry suggest that environmental sounds can cause significant changes in physiological function, the nature of the response varying with the quality, quantity and combination of sounds present (Brown and Glick, 1971). The compilation edited by Welch and Welch (1970) contains much of the published information which is currently available treating the effects of sounds upon biological organisms. Most of these compiled reports consider sound as a stress factor and observe the adverse effects on farm animals and other species exposed to sonic booms, freeway noises and other industrial sounds. Other reported research indicates that control of sound can be used with beneficial effects. It is generally recognized that different vocalizations of birds transmit meaningful information to other birds (Fringes and lumber, 1954; Lanyon and Tavolga, 1960). Jackson (1970) recorded what he termed "happy" singing sounds of hens on nest and played them back to hysteria prone flocks and succeeded in reducing the incidence of flock
hysteria. Popular publications have contained reports that music can be used to increase production of dairy cows, and recent studies indicate that swine may also respond in a favorable manner (Breeden, 1972). If quantitative and qualitative differences in sounds can be discerned by livestock species, then control of such sounds might profitably be used to enhance production. This study was conducted to evaluate the effects of two types of music played at two levels of intensity upon the growth rate and performance of broiler chickens. MATERIALS AND METHODS One hundred eight-day old H and N meat chicks were individually identified then allotted randomly into five groups of 20 chicks. Each group was housed in a cage 120 by 230 centimeters with a wire floor 90 centimeters above the ground and a tin room 70 centimeters above the floor. The cages were spaced 90 centimeters apart with baled hay stacked between them to serve as a sound barrier. The hay bales extended approximately one meter above and three meters beyond the walls of each cage. Though the bales were unpretentious in appearance, they 619
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
ABSTRACT One hundred eight-day old meat type chicks were randomly allotted into a control group and four music exposure treatment groups as follows: high level dinner music, low level dinner music, low level rock and roll music, and high level rock and roll music. Low level music reached a maximum decibel reading of 70 and high level music a maximum reading of 85. Feed consumption by group and individual weights were determined weekly during a nine-week feeding period. Feed consumption by groups was very similar and did not indicate any apparent tranquilizing effect or stress associated with treatments. Final live weight and carcass weight of the high level rock and roll group were somewhat less heavy than the others with the difference between low level dinner (1491 g.) and high level rock and roll (1398 g.) approaching statistical significance (P < .1).
620
RESEARCH NOTES
mined. One bird was eliminated from group 3 during the third week after a leg was accidentally broken during weighing. Group 4 was also reduced to 19 birds by a death loss during the eighth week. Weight data were analyzed by the method of fitting constants in a two-factor table and analysis of variance (Snedecor, 1956). Sex adjusted averages were compared to evaluate the treatment effects. RESULTS AND DISCUSSION Birds in each of the four music treatment groups were frightened by their initial exposure to music. Most of the birds in each cage piled up in the corners farthest from the speakers. Others laid flat on the floor with their necks outstretched and their eyes closed. This reaction gradually decreased through the first week and was not observed after that time. Thereafter, the birds distributed evenly throughout the cage with no apparent reluctance to stand directly in front of the speakers. By the end of the second week, birds in each of the groups exposed to music had started to intermittently twitch their heads in a jerking motion. This behavior continued through the rest of the experiment. Twitching was also observed among the control group, but only infrequently. If a manifestation of nervousness, it was apparently not reflected in differences in feed consumption. The cumulative feed consumed by each of the five groups during the study was very similar. Expressed as total feed per bird, consumption values averaged 4980, 5244, 4958, 5071 and 5144 grams for groups 1 through 5, respectively. (Table 1). Final weights are given in Table 1. Weights of the controls, low level dinner and low level rock and roll groups (2019, 2044 and 2031 grams, respectively) were intermediate to the high level dinner (2053 g.) and the high level rock and roll (1914 g.) groups. Though the 112 gram difference between the latter two groups was not statistically significant (P >
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
did provide an effective sound barrier between treatment groups. Cages housing groups 2, 3, 4 and 5 were each equipped with an 8-inch speaker placed at one end of the cage. Music was tape recorded and played continuously for 12 hours each day between 8:00 a.m. and 8:00 p.m. This time period corresponded to most of the daylight hours when the chicks were awake and active. Due to the nature of the physical facilities, no artificial light was provided. All sound levels were periodically monitored on the B scale of a General Radio Sound Level Meter placed in the middle of the cage floor. Group 1 (control) received an ambient noise level of about 60 db., which consisted primarily of chicken noises. Groups 2, 3, 4 and 5 received music treatments designated as follows: (2) high level dinner music; (3) low level dinner music; (4) low level rock and roll music; and (5) high level rock and roll music. The same dinner music was played to groups 2 and 3 and the same rock and roll music to groups 4 and 5, with sound levels regulated by a volume control. Low levels for each type music were regulated so that louder tones registered a maximum of 70 db. Louder tones of the high level groups registered a maximum of 85 db. Hou and Blaine (1971) observed that the hearing range of the chicken is somewhat comparable to that of humans. Prolonged exposure to sound levels of 80 db. is close to, but below that generally believed to cause permanent hearing impairment (Davis, 1970). A slightly higher level was adopted for this study as a level which might be associated with stress as reflected in rate and efficiency of gain. Feed was supplied on an ad libitum basis and consumption calculated weekly for each group. Birds were individually weighed weekly through a 9-week feeding period. At the time of slaughter, final live weights and dressed warm carcass weights were deter-
621
RESEARCH NOTES
TABLE 1.—Treatment means for feed consumption, live weight, warm dressed carcass weight and percent yield Feed consumption Carcass Live per % Yield weight (g.) weight (g.) Treatment' bird (g.) 1 72.3 1461 2020 4980 72.0 1480 2053 5244 2 72.9 1491 2045 4958 3 73.1 1486 2032 5071 4 72.0 1398 1942 5144 5 'Treatment groups: 1 = Control; 2 = high level dinner music; 3 = low level dinner music; 4 low level rock and roll music; 5 = high level rock and roll music. enhance production over the absence of music or whether loud rock and roll music causes stress and a resultant reduction in performance. REFERENCES Breeden, L., 1972. Effect of music on hog production. Hog Farm Management, 9 (11): 16. Brown, W. H., and B. Glick, 1971. Selected physiological responses of chickens. Amer. Soc. Agr. Eng. 14: 508-510. Christensen, A. C , and R. L. Nelson, 1971. Unpublished data. California State Polytechnic University, Pomona, California. Davis, H., and S. R. Silverman, 1970. Hearing and Deafness. Third Ed. Holt, Rinehart and Winston, New York. Fringes, H., and J. Jumber, 1954. Preliminary studies on the use of specific sounds to repel starlings from objectionable roosts. Science, 119: 318-319. Hou, Su-Ming, and M. A. Boone, 1971. The audibility curve of the chicken. Poultry Sci. 50: 1586. Jackson, D., 1970. Sound therapy for avian hysteria. Poultry Digest, 29: 286-287. Lanyon, W. E., and W. N. Tavolga, 1960. Animal Sounds and Communications. American Institute of Biological Sciences, Pub. No. 7, Washington. Snedecor, G. W., 1956. Statistical Methods. Iowa State University Press, Ames, Iowa. Welch, B. L., and A. S. Welch, 1970. Physiological Effects of Noise. Plenum Press, New York.
APRIL 10, 1975. DISTILLERS FEED CONFERENCE, GALT HOUSE, LOUISVILLE,
KENTUCKY
APRIL 30, MAY 1-2, 1975. FACT FINDING CONFERENCE, POULTRY AND EGG INSTITUTE OF AMERICA, NEW ORLEANS, LOUISIANA JULY 28-30, 1975. 67th ANNUAL MEETING OF THE AMERICAN SOCIETY OF ANIMAL SCIENCE, COLORADO STATE UNIVERSITY, FORT COLLINS, COLORADO
Downloaded from http://ps.oxfordjournals.org/ at Carleton University on June 26, 2015
.1), these results were of the same magnitude as those obtained in a preliminary study (Christensen and Nelson, 1971) contrasting dinner music with rock and roll music, both played at approximately 85 to 90 db. Average dressed carcass weights (Table 1) differed slightly from the live weights in order, group 3 being heaviest at 1491 g. and group 5 lightest at 1398 g. (P < .1). This difference in order of groups from live to dressed weights is reflected in slight differences in yield (Table 1). However, there is no indication of any relationship between yield and music treatment to which the various groups were subjected. Heart and liver weights and gross examination of other organs was made on all birds. No abnormalities were found and no differences observed which could be ascribed to treatment effects. Though the results of this study are inconclusive, they do suggest some perception by the chick, which is reflected in a change in growth performance, to loud levels of contrasting types of music. Further study would have to be undertaken to demonstrate whether dinner type music can be used to