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A Survey and Overview of Lighting Practices in the U. S. Turkey Breeder Industry
81999Applied Poultry Science, Inc.
A SURVEY AND OVERVIEW OF LIGHTING PRACTICES IN THE U S . TURKEY BREEDER INDUSTRY J. L. GRIMES' and T.D.SIOPES Department of Poultry Science, Box 7608, North Carolina State Universiy, Raleigh, NC 27695-7608 Phone: (919) 515-5406 F M : (919) 515-7070
keys, there are many options in the type of light DESCFUPTION OF PROBLEM to use, how much light to use, and when to use One definition of light relevant to poultry breeders is a visible radiation that stimulates reproductive function. In this regard light has two primary functions in addition to vision: synchronizing various rhythmic activities in the body and inducing hormone production [l]. Both of these functions are essential for optimum turkey breeder reproductive performance. For managers of poultry such as tur1
To whom correspondence should be addressed
it. Even though our knowledge of the effects of light on turkey production may not be complete, production managers, flock service personnel, and producers do have a substantial knowledge base to draw on in order to provide light conditions for optimum or near optimum production. With this in mind, this paper is intended to provide results of a survey of the U.S. turkey
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
Primary Audience: Flock Supervisors, Turkey Breeder Growers, Turkey Hatchery Managers
JAPR LIGHTS FOR TURKEY BREEDERS
494
a survey consisting of eight questions (Table 1) addressing issues of light management was sent to turkey breeders located in major turkey-producing regions of the U.S. The overall intent was to ascertain the duration, intensity, and type of lighting used in the turkey industry and to get an estimate of the perceived level of satisfaction with current lighting practices. The emphasis of the survey and this report is toward turkey breeder hens, with some comments on turkey breeder toms.
breeder industry on some basic light management practices, and to provide technical comments about these practices.
MATERIALS AND METHODS
'ABLE 1, Questions and responses for a lighting survey of turkey breeder industry personnel IUESIION
QUESTON
RESPONSE
#
TO
I
a. Howmanyhoursof light/dayareused to initiate photostimulation of breeder hens? ~-
~~
I
12.5 hr 13.5 hr 3 1 S I
14hr 72
1
1.5 hr 20
4 4 1
18hr 22
~
is the final day length (hr of
15hr h I
16hr 28
17hr
I
Off 67
I
7
I
I
I I
16hr 0
Both 1
26
Is h a s e s h i f t i n g used d u r i n g egg proSuetion? Is step-down used during prelay followed by step-up during the lay penod? 5
Is intermittent lighting used for:
No
Yes 2
98
13
87
Are you satisfiedwith your light program for your hens?
Yes
No
87
13
7
Are you satisfied with your light program for your toms?
Yes 82
No 18
8
Is light intensity an area of concern for you
Yes
No
a. egg production? b. semen production? 6
in: a. overall?
69
31
b. blackout house?
S8
42
I E.breeder barn? 9
Please provide comments, needs, or requests about lighting:
1
42
I
58
The most common remonses were: What is the best lighting program for hens and toms?
Can we do better than what we are currentlv doine? What are light intensity requirements for our breedel turkeys?
'IN = Incandescent, FL = Fluorescent, HPS = High pressure sodium, and M = Mercury.
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
Poultry respond to three characteristics of any light period: length, intensity, and color. Color refers to the spectral output of light and is determined by the type of light f'urture used. One should consider each of the above factors when preparing a lighting program for turkey breeder hens. Therefore,
Review Article GRIMES and SIOPES
495
the turkey breeder industry this is most comRESULTS AND DISCUSSIONmonly accomplished artificially by the use of A summary of the survey responses is provided in Table 1.Thirty-nine surveys were returned. All responses were from personnel representing commercial turkey breeder complexes with one response per complex.
PHASE-SHIFTING, STEP-UP/STEPDOWN, INTERMITTENT, AND AHEMERAL LIGHTING The use of phase shifting (Question 3, Table 1) was indicated by 47% of the survey respondents, while 53% indicated that they do not use phase shifting of light. "Phase shifting" refers to the practice of adding 2 to 4 hr of light to 1 day/wk for breeder hens during the egg production period [4]. It is most commonly used during the summer egg production season as a method to control broodiness in hens. The mechanism by which phase shiftingworks is not known, but the associated reduction in incidence of broodiness results in more eggs. Therefore, where broodiness is a problem this technique can be valuable. The majority (87%) of respondents indicated that they do not use step-down lighting
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
DURATION OF LIGHT Question 1 asked the respondents to indicate the number of hr of light/day used to initiate lighting of their turkey breeder hens, the final day length used during lay, and whether the additional light was added at the beginning of the day, the end of the day, or both. The majority of respondents (72%) initiate lay in turkeys with 14 hr of light/day, with most of the rest (20%) using 15 hr. For final day length, most respondents use 17hr (44%); others use 16 (28%) and 18 hr (22%). The majority of respondents add light at the beginning (on-time) of the day (67%), with most of the rest adding light at both the beginning and end (off) of the day (26%). One respondent indicated that during winter the day length used at the start of photostimulation is 14 hr and during the summer the day length used is 16 hr. Birds can measure day length, and turkey hens measure the length of time from sunrise, or time at which lights are turned on, until sunset, or time at which lights are turned off. When using natural lighting, it is recommended that one calculate day length from 30 min before sunrise to 30 min after sunset. Long day length is responsible for both photostimulation of reproduction and photorefractoriness, which includes and is characterized by the cessation of reproduction. It is important to note that although photostimulation and photorefractoriness have opposing effects on the hen's reproductive system, they are both natural processes caused by long days. Each of these has important and beneficial effects on birds in nature (including wild turkeys), but photorefractoriness is a negative phenomenon for domestic commercial turkey breeder hens because it diminishes overall egg production by shortening the lay period. A proper sequence of short days will end photorefractoriness and restore photosensitivity in turkey hens 121. In nature this is accomplished by the short days of winter; in
light-controlled (blackout) houses for firstcycle hens and induced molted hens to provide a minimum of 8 wk of 6-8 hr of light/day. Critical day length (CDL) can be defined as the minimum number of hours of light needed by the hen to induce normal egg production. This is generally what is meant by "long day length," that is, any day length greater than the CDL. Although 12 hr of light is normally agreed to be a long day length and thus stimulatory for turkey hens, most managers use 14 to 18hr of light/day to stimulate hens for egg production. It is important to note that critical day length is not the same year-round [3], and therefore the meaning of "long day length varies by season. During winter the CDL is about 11.5 hr and during the summer it is greater than 14 hr. Day lengths much greater than these do not always result in greater egg production. If day length is too long, the overall time in production can be reduced by photorefractoriness (diminished response to long day lengths). Day length should be just longer than the CDL. The goal is to maximize photostimulation while minimizing photorefractoriness, and this is accomplished by not overphotostimulating hens during the winter and not under-photostimulating hens during the summer. Thus, the use of different photoperiods in winter vs. summer by one of the survey respondents is quite justified.
'R 4%
LIGHT INTENSITY The survey inquired "is light intensity an area of concern for you?" (Question 8). Most indicated yes for birds in the blackout house (69%) and overall (69%). However, only 48% indicated that light intensity is a concern for birds in the breeder house. Light intensity is important because a threshold exists below which breeder perfor-
mance is less than optimal. Light intensity refers to the lux or foot candles (ft-cd) of light produced by a lamp or the sun as measured by a conventional light meter (photometer). Multiplying ft-cd by 10.7 will convert to lux so that 5 ft-cd equals approximately 50 lux. It should be noted that reference to light intensity levels in lux or ft-cd should be made with regard to light type. Comparisons of ft-cd levels among different light types (colors) is not accurate unless correction factors are applied [SI. Several breeder guides currently recommend 12 ft-cd (128 lux) as a minimum for breeder hens. However, it has been reported that normal egg production occurs in Large White turkey breeder hens at a mean intensity of 30 to 50 lux [9, 101. Light intensity requirements are affected by the genetics of the hen, and specific requirements should be determined by strain [9]. It is generally assumed that there is no practical upper limit for light intensity since hens stimulated by sunlight produce eggs at normal rates. Control of light intensity during the dark phase of the daily light restriction (short days) treatment during the prelay period (or induced molting) is very important, a fact expressed by respondents of this survey. During the dark phase the best light intensity level is none at all, but an absence of light is not an absolute requirement. That is, "brown-out" is acceptable. However, light leaks that result in brown-outs with light intensities at or over 0.05 ft-cd (approximately twice that of full moonlight) must be eliminated. Light intensity of the daily light phase during any @trestriction treatment period should be at least 3 to 5 ft-cd. TYPE (COLOR) OF LIGHT Numerous types of light sources are available to the poultry industry, with each type having its own characteristics. Question 2 of the survey was given to determine what type of light is most commonlyused in turkey breeder houses. Most of the respondentsindicated that they use High Pressure Sodium (HPS, 56%), followed by incandescent (IN, 24%), and fluorescent (FL, 19%). Many indicated that multiple light types are used in various barns or houses within a company, but even in those cases more than 50% of the units contain HPS lights. Respondents indicated use of various
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
during prelay followedby step-up lighting during the egg production period (Question 4, Table 1). However, when used, it is utilized year-round. This practice apparently arose to bring hens into lay gradually and to prevent problems associated with the laying of initial eggs such as uterine prolapse [SI. Even though it is known that intermittent lighting can save electricity and feed and has no adverse effects on reproductive performance of turkeys [6J, the majority of respondents indicated that they do not use intermittent lighting (Question 5, Table 1) for egg production (98%) or semen production (87%). Ahemeral lighting refers to light-dark cycles that sum to something other than 24 hr. For example, a cycle can be 15 hr of light and 13 hr of dark, resulting in a 28-hr "day." In contrast, a cycle of 15 hr of light and 9 hr of dark results in a normal 24-hr day. This type of lighting has been demonstrated to be particularly useful for increasing egg size in turkeys during early lay [q.However, it must be used only at the start of photostimulation;continuing the ahemeral photoperiod past peak egg production will have detrimental effects. One can shift the light cycle back to 24 hr (from 15:13 to 159) once satisfactory egg size has been obtained or no later than the time of peak egg production. It should be noted that ahemeral light cycles and intermittent light programs require light control housing. In addition, they both require changes to the customary daily schedules of husbandry. These requirements pose signifcant problems for the majority of the turkey breeder industry and are probably the basis for the programs' lack of use. However, these lighting programs have been tested for use in current facilities because of their potential benefits: improving early egg size, advancing the age at photostimulation, and reducing use of feed and electricity.
LIGHTS FOR TURKEY BREEDERS
Review Article 497
GRIMES and SIOPES
mance of turkeys is best with the longer (orange-red) wavelengths of light. This, plus the efficiency of light production [16, 191, is why use of HPS light has become so widespread in the turkey industry. STATUS OF LIGHT MANAGEMENT METHODS The majority of respondents are satisfied with their light management for hens (87%, Question 6) and toms (82%, Question 7). Even with this relatively high level of satisfaction it was clear that there still exist areas of concern. This was indicated by the most common comments and/or requests of the survey respondents: (1) What is the best lighting program for hens and toms?; (2) Can we do better than what we are currently doing?; and (3) What are the specific light intensity requirements for turkey breeders?
CONCLUSIONS AND APPLICATIONS 1. Turkey industry personnel have a good understanding of light management for turkey breeders. 2. Managing light programs by season of the year may be an avenue for turkey industry personnel to explore. 3. Customizing light programs with respect to phase shifting, step-up/step-down lighting, intermittent lighting, and ahemeral lighting may be an option for individual companies or complexes to consider.
REFERENCES AND NOTES 1. Siopes, T.D., 1982. Physiology of light perception: Lighting programs in and out of season. Pages 64-69 in: Proc. Symp. on Turkey Reproduction, Raleigh, NC.
8. Wineland, M.J. and T.D. Siopes, 1992. A comparison of li ht intensity measurements of different light sources. Appl. Poultry Res. 1:287-290.
2. Siopes, T.D., 1989. Prelay light restriction of turkey hens: Day length versus exposure time. Poultry Sci. 6&1337-1341.
9. Neslor, ICE and K.I. Brown, 1972. Light intensity and reproduction of turkey hens. PoultIy Sci. S1:117-121.
3. Siopes, T.D., 1994. Critical day lengths for egg production and hotorefractoriness in .the domestic turkey. Poultry Sci. &:19061913. 4. Clausen, S., 1989. Lighting programs for summer production. Pages 17-19 in: Proc. Intl. Symp. on urkey Reproduction, Raleigh, NC.
!F
5. Wagoner, P. and M.E El Halawani, 1993. Stepdown step-up lighting. P a g e s 5 4 in: Proc. 3rd Intl. Symp. on Turkey Reproduction, Raleigh, NC.
10. Siopes, T.D., 1991. Light intensityeffects on reproductive performance of turkey breeder hens. Poultry Sci. 70:2049-2054. 11. Bissonette, T.H., 1932. Studies on the sexual cycle in birds. VI. Effect of white, green, and red lights of equal luminous intensity on the testis activity of the M). Physiol. Zool. European starling (5:92-123.
6. Siopes, T.D. and R Pynak, 1990. Effect of intermittent lightin on the reproductive performance of firstyear and recycid turkey hens. Poultly Sci. 69:142-149.
12. Benoit, J. and L Ott, 1944. External and internal factors in sexual activity. Effect of irradiation and different wavelengths on the mechanism of photostimulation of the hypophysis and on testicular growth in the immature duck. Yale J. Biol. Med. 1727-46.
7. Siopes, T.D., 1997. Lighting turkey breeder hens. Pages 14-16 in: Proc. 4th Intl. Symp. on Turkey Reproduction, Raleigh, NC.
13. Woodward, A.E, J.A. Moore, and W.O. Wilson, 1992. A comparison of light intensity measurements of different light sources. J. Appl. Poultly Res. 1237-290.
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
kinds of FL lights, including cool white, warm white deluxe, and HO sunlight. The goal of using these or any light source is to provide light that will maximize the desired performance. The primary differences among the various light sources is the color output and the efficiency of light production. The results of the survey clearly indicate that the turkey breeder industry has found HPS lighting to be the best in regard to these factors. From the existing scientific literature it is clear that turkeys can respond to all colors of light and that reproductive performance is best with the longer (orange-red) wavelengths of visible light I l l , 12, 13, 14, 15, 161. This response is intensity dependent [17], and if light is given at a normal intensity and equalized for each color, the reproductive performance of turkeys is the same for each color of light [MI. However, under practical, commonly used conditions, reproductive perfor-
JAPR 498 14. Foss, D.C., LB. Carew, Jr., and EL Arnold, 1972. Physiological development of cockerels as influenced by selected wavelengths of environmental light. Poultry SCI. 51:192-1927. 15. Oishi, T. and J.K. Lauber, 1973. Photoreception in the photosexual response of quail. 11. Effects of intensity and wavelengths, h e r . J. Physiol. 225:880-886. 16. Lewis, P.D. and T.R Morris, 1998. Responses of domestic oultIy tovarious light sources. World’s Poultry Sci. J. 54&arch):7-25.
LIGHTS FOR TURKEY BREEDERS 17. Siopes, T.D.,1991. Spectral and intensity effects of light on reproductive performanceof turkey hens. Poultry Sci. 70111 (Abs). 18. Pvrzak, R and T.D. SioDes. 1986. Effect of light uali on egg production of caged turkey hens. Pouhy Zci. 2199-200.
19. Fells, J.V., AT. Lcightoo, Jr., D.M. Denbow, and RM. Hulel, 1990.Influence of light sourcesonthe growth and reproduction of Large White turkeys. Poultry Sci. 69576583.
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
A SURVEY AND OVERVIEW OF LIGHTING PRACTICES IN THE U S . TURKEY BREEDER INDUSTRY J. L. GRIMES' and T.D.SIOPES Department of Poultry Science, Box 7608, North Carolina State Universiy, Raleigh, NC 27695-7608 Phone: (919) 515-5406 F M : (919) 515-7070
keys, there are many options in the type of light DESCFUPTION OF PROBLEM to use, how much light to use, and when to use One definition of light relevant to poultry breeders is a visible radiation that stimulates reproductive function. In this regard light has two primary functions in addition to vision: synchronizing various rhythmic activities in the body and inducing hormone production [l]. Both of these functions are essential for optimum turkey breeder reproductive performance. For managers of poultry such as tur1
To whom correspondence should be addressed
it. Even though our knowledge of the effects of light on turkey production may not be complete, production managers, flock service personnel, and producers do have a substantial knowledge base to draw on in order to provide light conditions for optimum or near optimum production. With this in mind, this paper is intended to provide results of a survey of the U.S. turkey
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
Primary Audience: Flock Supervisors, Turkey Breeder Growers, Turkey Hatchery Managers
JAPR LIGHTS FOR TURKEY BREEDERS
494
a survey consisting of eight questions (Table 1) addressing issues of light management was sent to turkey breeders located in major turkey-producing regions of the U.S. The overall intent was to ascertain the duration, intensity, and type of lighting used in the turkey industry and to get an estimate of the perceived level of satisfaction with current lighting practices. The emphasis of the survey and this report is toward turkey breeder hens, with some comments on turkey breeder toms.
breeder industry on some basic light management practices, and to provide technical comments about these practices.
MATERIALS AND METHODS
'ABLE 1, Questions and responses for a lighting survey of turkey breeder industry personnel IUESIION
QUESTON
RESPONSE
#
TO
I
a. Howmanyhoursof light/dayareused to initiate photostimulation of breeder hens? ~-
~~
I
12.5 hr 13.5 hr 3 1 S I
14hr 72
1
1.5 hr 20
4 4 1
18hr 22
~
is the final day length (hr of
15hr h I
16hr 28
17hr
I
Off 67
I
7
I
I
I I
16hr 0
Both 1
26
Is h a s e s h i f t i n g used d u r i n g egg proSuetion? Is step-down used during prelay followed by step-up during the lay penod? 5
Is intermittent lighting used for:
No
Yes 2
98
13
87
Are you satisfiedwith your light program for your hens?
Yes
No
87
13
7
Are you satisfied with your light program for your toms?
Yes 82
No 18
8
Is light intensity an area of concern for you
Yes
No
a. egg production? b. semen production? 6
in: a. overall?
69
31
b. blackout house?
S8
42
I E.breeder barn? 9
Please provide comments, needs, or requests about lighting:
1
42
I
58
The most common remonses were: What is the best lighting program for hens and toms?
Can we do better than what we are currentlv doine? What are light intensity requirements for our breedel turkeys?
'IN = Incandescent, FL = Fluorescent, HPS = High pressure sodium, and M = Mercury.
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
Poultry respond to three characteristics of any light period: length, intensity, and color. Color refers to the spectral output of light and is determined by the type of light f'urture used. One should consider each of the above factors when preparing a lighting program for turkey breeder hens. Therefore,
Review Article GRIMES and SIOPES
495
the turkey breeder industry this is most comRESULTS AND DISCUSSIONmonly accomplished artificially by the use of A summary of the survey responses is provided in Table 1.Thirty-nine surveys were returned. All responses were from personnel representing commercial turkey breeder complexes with one response per complex.
PHASE-SHIFTING, STEP-UP/STEPDOWN, INTERMITTENT, AND AHEMERAL LIGHTING The use of phase shifting (Question 3, Table 1) was indicated by 47% of the survey respondents, while 53% indicated that they do not use phase shifting of light. "Phase shifting" refers to the practice of adding 2 to 4 hr of light to 1 day/wk for breeder hens during the egg production period [4]. It is most commonly used during the summer egg production season as a method to control broodiness in hens. The mechanism by which phase shiftingworks is not known, but the associated reduction in incidence of broodiness results in more eggs. Therefore, where broodiness is a problem this technique can be valuable. The majority (87%) of respondents indicated that they do not use step-down lighting
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
DURATION OF LIGHT Question 1 asked the respondents to indicate the number of hr of light/day used to initiate lighting of their turkey breeder hens, the final day length used during lay, and whether the additional light was added at the beginning of the day, the end of the day, or both. The majority of respondents (72%) initiate lay in turkeys with 14 hr of light/day, with most of the rest (20%) using 15 hr. For final day length, most respondents use 17hr (44%); others use 16 (28%) and 18 hr (22%). The majority of respondents add light at the beginning (on-time) of the day (67%), with most of the rest adding light at both the beginning and end (off) of the day (26%). One respondent indicated that during winter the day length used at the start of photostimulation is 14 hr and during the summer the day length used is 16 hr. Birds can measure day length, and turkey hens measure the length of time from sunrise, or time at which lights are turned on, until sunset, or time at which lights are turned off. When using natural lighting, it is recommended that one calculate day length from 30 min before sunrise to 30 min after sunset. Long day length is responsible for both photostimulation of reproduction and photorefractoriness, which includes and is characterized by the cessation of reproduction. It is important to note that although photostimulation and photorefractoriness have opposing effects on the hen's reproductive system, they are both natural processes caused by long days. Each of these has important and beneficial effects on birds in nature (including wild turkeys), but photorefractoriness is a negative phenomenon for domestic commercial turkey breeder hens because it diminishes overall egg production by shortening the lay period. A proper sequence of short days will end photorefractoriness and restore photosensitivity in turkey hens 121. In nature this is accomplished by the short days of winter; in
light-controlled (blackout) houses for firstcycle hens and induced molted hens to provide a minimum of 8 wk of 6-8 hr of light/day. Critical day length (CDL) can be defined as the minimum number of hours of light needed by the hen to induce normal egg production. This is generally what is meant by "long day length," that is, any day length greater than the CDL. Although 12 hr of light is normally agreed to be a long day length and thus stimulatory for turkey hens, most managers use 14 to 18hr of light/day to stimulate hens for egg production. It is important to note that critical day length is not the same year-round [3], and therefore the meaning of "long day length varies by season. During winter the CDL is about 11.5 hr and during the summer it is greater than 14 hr. Day lengths much greater than these do not always result in greater egg production. If day length is too long, the overall time in production can be reduced by photorefractoriness (diminished response to long day lengths). Day length should be just longer than the CDL. The goal is to maximize photostimulation while minimizing photorefractoriness, and this is accomplished by not overphotostimulating hens during the winter and not under-photostimulating hens during the summer. Thus, the use of different photoperiods in winter vs. summer by one of the survey respondents is quite justified.
'R 4%
LIGHT INTENSITY The survey inquired "is light intensity an area of concern for you?" (Question 8). Most indicated yes for birds in the blackout house (69%) and overall (69%). However, only 48% indicated that light intensity is a concern for birds in the breeder house. Light intensity is important because a threshold exists below which breeder perfor-
mance is less than optimal. Light intensity refers to the lux or foot candles (ft-cd) of light produced by a lamp or the sun as measured by a conventional light meter (photometer). Multiplying ft-cd by 10.7 will convert to lux so that 5 ft-cd equals approximately 50 lux. It should be noted that reference to light intensity levels in lux or ft-cd should be made with regard to light type. Comparisons of ft-cd levels among different light types (colors) is not accurate unless correction factors are applied [SI. Several breeder guides currently recommend 12 ft-cd (128 lux) as a minimum for breeder hens. However, it has been reported that normal egg production occurs in Large White turkey breeder hens at a mean intensity of 30 to 50 lux [9, 101. Light intensity requirements are affected by the genetics of the hen, and specific requirements should be determined by strain [9]. It is generally assumed that there is no practical upper limit for light intensity since hens stimulated by sunlight produce eggs at normal rates. Control of light intensity during the dark phase of the daily light restriction (short days) treatment during the prelay period (or induced molting) is very important, a fact expressed by respondents of this survey. During the dark phase the best light intensity level is none at all, but an absence of light is not an absolute requirement. That is, "brown-out" is acceptable. However, light leaks that result in brown-outs with light intensities at or over 0.05 ft-cd (approximately twice that of full moonlight) must be eliminated. Light intensity of the daily light phase during any @trestriction treatment period should be at least 3 to 5 ft-cd. TYPE (COLOR) OF LIGHT Numerous types of light sources are available to the poultry industry, with each type having its own characteristics. Question 2 of the survey was given to determine what type of light is most commonlyused in turkey breeder houses. Most of the respondentsindicated that they use High Pressure Sodium (HPS, 56%), followed by incandescent (IN, 24%), and fluorescent (FL, 19%). Many indicated that multiple light types are used in various barns or houses within a company, but even in those cases more than 50% of the units contain HPS lights. Respondents indicated use of various
Downloaded from http://japr.oxfordjournals.org/ at Mount Allison University on June 12, 2015
during prelay followedby step-up lighting during the egg production period (Question 4, Table 1). However, when used, it is utilized year-round. This practice apparently arose to bring hens into lay gradually and to prevent problems associated with the laying of initial eggs such as uterine prolapse [SI. Even though it is known that intermittent lighting can save electricity and feed and has no adverse effects on reproductive performance of turkeys [6J, the majority of respondents indicated that they do not use intermittent lighting (Question 5, Table 1) for egg production (98%) or semen production (87%). Ahemeral lighting refers to light-dark cycles that sum to something other than 24 hr. For example, a cycle can be 15 hr of light and 13 hr of dark, resulting in a 28-hr "day." In contrast, a cycle of 15 hr of light and 9 hr of dark results in a normal 24-hr day. This type of lighting has been demonstrated to be particularly useful for increasing egg size in turkeys during early lay [q.However, it must be used only at the start of photostimulation;continuing the ahemeral photoperiod past peak egg production will have detrimental effects. One can shift the light cycle back to 24 hr (from 15:13 to 159) once satisfactory egg size has been obtained or no later than the time of peak egg production. It should be noted that ahemeral light cycles and intermittent light programs require light control housing. In addition, they both require changes to the customary daily schedules of husbandry. These requirements pose signifcant problems for the majority of the turkey breeder industry and are probably the basis for the programs' lack of use. However, these lighting programs have been tested for use in current facilities because of their potential benefits: improving early egg size, advancing the age at photostimulation, and reducing use of feed and electricity.
LIGHTS FOR TURKEY BREEDERS
Review Article 497
GRIMES and SIOPES
mance of turkeys is best with the longer (orange-red) wavelengths of light. This, plus the efficiency of light production [16, 191, is why use of HPS light has become so widespread in the turkey industry. STATUS OF LIGHT MANAGEMENT METHODS The majority of respondents are satisfied with their light management for hens (87%, Question 6) and toms (82%, Question 7). Even with this relatively high level of satisfaction it was clear that there still exist areas of concern. This was indicated by the most common comments and/or requests of the survey respondents: (1) What is the best lighting program for hens and toms?; (2) Can we do better than what we are currently doing?; and (3) What are the specific light intensity requirements for turkey breeders?
CONCLUSIONS AND APPLICATIONS 1. Turkey industry personnel have a good understanding of light management for turkey breeders. 2. Managing light programs by season of the year may be an avenue for turkey industry personnel to explore. 3. Customizing light programs with respect to phase shifting, step-up/step-down lighting, intermittent lighting, and ahemeral lighting may be an option for individual companies or complexes to consider.
REFERENCES AND NOTES 1. Siopes, T.D., 1982. Physiology of light perception: Lighting programs in and out of season. Pages 64-69 in: Proc. Symp. on Turkey Reproduction, Raleigh, NC.
8. Wineland, M.J. and T.D. Siopes, 1992. A comparison of li ht intensity measurements of different light sources. Appl. Poultry Res. 1:287-290.
2. Siopes, T.D., 1989. Prelay light restriction of turkey hens: Day length versus exposure time. Poultry Sci. 6&1337-1341.
9. Neslor, ICE and K.I. Brown, 1972. Light intensity and reproduction of turkey hens. PoultIy Sci. S1:117-121.
3. Siopes, T.D., 1994. Critical day lengths for egg production and hotorefractoriness in .the domestic turkey. Poultry Sci. &:19061913. 4. Clausen, S., 1989. Lighting programs for summer production. Pages 17-19 in: Proc. Intl. Symp. on urkey Reproduction, Raleigh, NC.
!F
5. Wagoner, P. and M.E El Halawani, 1993. Stepdown step-up lighting. P a g e s 5 4 in: Proc. 3rd Intl. Symp. on Turkey Reproduction, Raleigh, NC.
10. Siopes, T.D., 1991. Light intensityeffects on reproductive performance of turkey breeder hens. Poultry Sci. 70:2049-2054. 11. Bissonette, T.H., 1932. Studies on the sexual cycle in birds. VI. Effect of white, green, and red lights of equal luminous intensity on the testis activity of the M). Physiol. Zool. European starling (5:92-123.
6. Siopes, T.D. and R Pynak, 1990. Effect of intermittent lightin on the reproductive performance of firstyear and recycid turkey hens. Poultly Sci. 69:142-149.
12. Benoit, J. and L Ott, 1944. External and internal factors in sexual activity. Effect of irradiation and different wavelengths on the mechanism of photostimulation of the hypophysis and on testicular growth in the immature duck. Yale J. Biol. Med. 1727-46.
7. Siopes, T.D., 1997. Lighting turkey breeder hens. Pages 14-16 in: Proc. 4th Intl. Symp. on Turkey Reproduction, Raleigh, NC.
13. Woodward, A.E, J.A. Moore, and W.O. Wilson, 1992. A comparison of light intensity measurements of different light sources. J. Appl. Poultly Res. 1237-290.
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kinds of FL lights, including cool white, warm white deluxe, and HO sunlight. The goal of using these or any light source is to provide light that will maximize the desired performance. The primary differences among the various light sources is the color output and the efficiency of light production. The results of the survey clearly indicate that the turkey breeder industry has found HPS lighting to be the best in regard to these factors. From the existing scientific literature it is clear that turkeys can respond to all colors of light and that reproductive performance is best with the longer (orange-red) wavelengths of visible light I l l , 12, 13, 14, 15, 161. This response is intensity dependent [17], and if light is given at a normal intensity and equalized for each color, the reproductive performance of turkeys is the same for each color of light [MI. However, under practical, commonly used conditions, reproductive perfor-
JAPR 498 14. Foss, D.C., LB. Carew, Jr., and EL Arnold, 1972. Physiological development of cockerels as influenced by selected wavelengths of environmental light. Poultry SCI. 51:192-1927. 15. Oishi, T. and J.K. Lauber, 1973. Photoreception in the photosexual response of quail. 11. Effects of intensity and wavelengths, h e r . J. Physiol. 225:880-886. 16. Lewis, P.D. and T.R Morris, 1998. Responses of domestic oultIy tovarious light sources. World’s Poultry Sci. J. 54&arch):7-25.
LIGHTS FOR TURKEY BREEDERS 17. Siopes, T.D.,1991. Spectral and intensity effects of light on reproductive performanceof turkey hens. Poultry Sci. 70111 (Abs). 18. Pvrzak, R and T.D. SioDes. 1986. Effect of light uali on egg production of caged turkey hens. Pouhy Zci. 2199-200.
19. Fells, J.V., AT. Lcightoo, Jr., D.M. Denbow, and RM. Hulel, 1990.Influence of light sourcesonthe growth and reproduction of Large White turkeys. Poultry Sci. 69576583.
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