- Email: [email protected]
The Use of All-Night Lights for Growing Turkeys
The Use of All-Night Lights for Growing Turkeys T. T. MILBY AND R. B. THOMPSON Department oj Poultry Husbandry, Oklahoma Agricultural and Mechanical College, Stillwater, Oklahoma (Received for publication October 28, 1940)
HE opinion has frequently been expressed that the use of artificial light at night aids the growth of baby chicks. An example of this is given by Ballard (1930) in a popular news story. A commercial poultryman was using all-night lights on his broilers and claimed that the birds took more exercise and ate more feed, therefore, they grew faster. The first experimental evidence bearing on this problem is given by Zoratan (1929) who gave chicks an extra feeding (of grain) in the evening by using kerosene lanterns. He claimed that the chicks so fed grew faster, than the controls and feathered one week sooner with lower mortality. The death losses were high on all lots and based on present standards the growth was extremely poor. More recently, LeMasurier and Branion (1939) observed that chicks raised in battery brooders grew faster than comparable chicks raised on the floor. They attributed this better growth to the fact that the batteries were heated with electric bulbs which supplied sufficient light to allow the chicks to eat at night. In this connection the work of Buckner, Insko, and Martin (1934) might also be cited. In studying the growth of White Leghorn chickens one lot was raised in a colony brooder house and two lots were started in battery brooders. These brooders were heated with hot water and artificial light beyond normal daylight was not used. Up to six weeks of age the battery raised chicks were larger than the pen raised chicks.
There is also a common opinion that the use of a dim light at night helps to prevent crowding and piling up. Since turkey poults seem to be more prone to crowd than chicks, the use of all-night lights should be especially valuable in reducing early mortality. No experimental evidence has been brought to the attention of the authors to substantiate this opinion. EXPERIMENTAL
In 1936 an experiment was begun at this station to determine the effect of all-night lights on the growth, viability, and economy of gain of young turkeys. The growth period was divided into three periods, starting or brooding, growing, and finishing. The first year these periods were 9, 18, and 27 weeks; subsequently they were set at 8, 20, and 28 weeks. At the end of the brooding period each lot was further divided at random into three and the following lighting schedule was maintained for the starting, growing, and finishing periods respectively: 1. 2. 3. 4. 5. 6.
Lights Lights Lights No lights No lights No lights
Lights Lights No lights No lights No lights Lights
Lights No lights Lights No lights Lights No lights
Trial 1 In this experiment, begun April 16,1936, several varieties of turkeys were used, the majority of the poults being of the Bronze variety. Viability was recorded for all but growth was summarized only for the Bronze
[332]
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
T
333
T H E USE OF ALL-NIGHT LIGHTS FOR GROWING TURKEYS TABLE 1.—Growth of Bronze poults hatched April 16, 1936 {trial 1) 9 weeks
27 weeks
18 weeks
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. -birds
Mean weight (pounds)
47 42
2.17+.06 2.14+.06
43 46
6.89+.20 7.26+.20
46 42
15.0+.27 15.2+.28
36 45
1.77+.06 1.85+ .05
42 41
5.26+.17 5.33+.17
40 43
9.6+.16 10.3+ .15
Males: No lights Females:
since the turkeys of the other breeds were considerably smaller. Four hundred poults were divided into two groups so that the progeny of the different breeding pens were distributed uniformly. The poults given all-night lights were started in home-made electric battery brooders in which the heat and light was furnished by light bulbs. The group without artificial light was started in a gas-heated battery brooder. When the poults were two weeks of age they were transferred to similar 12 by 16 foot colony brooder houses heated by gas burning brooders. During the first three weeks 27 poults died in the all-night light group and 49 in the group without lights. Most of the poults that died in the latter group were smothered by piling up shortly after they were transferred from the battery to the floor. No crowding occurred in the all-night light group. Mortality after three weeks of age was about the same in both groups and was due largely to blackhead after the turkeys
were transferred to pens with outdoor runs. The mean weights of the Bronze turkeys at 9, 18, and 27 weeks of age together with their standard errors are given in Table 1. Only those turkeys that survived long enough to be sexed were included in the averages. The varying numbers are due to the varying combinations of the six groups. Analysis of variance indicated that there were no significant differences between the six groups nor between all groups with lights and those without at any age. In other words, all-night lights did not influence growth. Trial 2 In 1937 the trial was conducted essentially the same as in the previous year except that Bronze poults only were used and the periods were 8, 20, and 28 weeks. The same brooding equipment was used as in the previous year. The mortality was again high on the no lights group, 18.1 percent as compared to
TABLE 2.—Growth of Bronze poults hatched April 16, 1937 {trial 2) 20 weeks
8 weeks No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
57 24
1.S8+.03 1.33+.04
46 34
8.62+.14 8 . 4 2 + . 16
37 38
15.3+.21 15.0±.21
44 34
1.46+.03 1.24+.04
38 38
6.52+.12 6.33+.12
45 29
10.0+.09 10.0+.11
Males No lights Females: No lights
28 weeks
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
No lights
334
T. T. MILBY AND R. B. THOMPSON TABLE 3.—Pounds offeed required to produce a pound of gain {trial 2) 0to8 weeks Lights No lights.
9 to 20 21 to 28 Total to weeks 28 weeks weeks 7.4 7.4
5.0 4.7
1.3 2.2
5.2 5.6
weeks to 20 weeks, and more thereafter. The varying sex ratio in the groups may account for this difference. Trial 3 Because of the difficulty encountered in regulating the gas brooders used in the previous trials all poults were started on the floor in the third trial. Electric brooders of identical design were used. A change was made in the ration used for starting the poults with a considerable increase in the rate of growth. Otherwise the plan used in the previous trials was followed. Two hundred Bronze poults were started in each group. There were no significant differences in the growth, mortality, or feed consumption. The growth statistics are given in Table 4; mortality and feed statistics in Table S.
TABLE 4.—Growth of Bronze poults hatched April 8, 1938 {trial 3) 8 weeks
Males: Lights No lights Females: No lights
20 weeks
28 weeks
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
87 95
2.36+.04 2.41+.03
76 87
11.2+ .13 11.4+ .12
83 75
18.4+.23 18.9+.24
71 65
1.97+.03 1.99+.04
64 61
8.11+.10 8 . 1 8 + . 10
55 62
11.6+ .12 11.8+ .11
TABLE 5.—Feed consumption and mortality {trial 3) Pounds feed to produce 1 pound of gain
Number dead to date
Lights No lights. . .
4 wks.
8 wks.
0 to 8 wks.
9 to 20 wks.
21 to 28 wks.
Total
30 31
42 38
2.6 2.5
5.3 4.9
7.2 7.4
5.5 5.4
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
8.8 percent in the lights groups to four weeks of age and 51 percent as compared to 29.4 percent to eight weeks. While the poults were in the battery brooder considerable difficulty was encountered in regulating the temperature in the gas heated brooders and the poults were badly chilled. No difficulty was experienced in the electric brooders. The heavy mortality was probably due to the chilling. The statistics on growth are given in Table 2. The difference in weight at eight weeks of age is highly significant but none of the other differences are significant. The poor growth of the no light group as well as the high mortality may be due to the chilling. By the time the poults were 20 weeks of age they had made up this difference. Feed consumption is given in Table 3. After the poults were eight weeks of age the feed consumption is not greatly different. It is probable that there is an error in the feed for the first eight weeks since 1.3 pounds of feed per pound of gain is not reasonable. The group without lights consumed less feed per pound of gain from 8
33S
T H E USE OF ALL-NIGHT LIGHTS FOE GROWING TURKEYS
Trial 4 Although in two of three previous trials all-night lights had not benefited growth and the third trial was open to question it occurred to the authors that all brooders TABLE 6.—Mean weights at 8 weeks of age. Poults hatched April 22, 1939 {trial 4)
Gas—lights Gas—no lights... Wood—lights Wood—no lights.
9 9 mean (pounds)
2.02+.07 2.20±.06 2.22+.06 2.27+.06
1.78+.05 1.83+.05 1.94+.05 1.85+.05
used furnished some incidental light. In the case of the gas burning brooders the pilot flame and in case of the electric brooders the pilot light gave some illumination. Observation after dark indicated that in the pen without lights an occasional poult did eat a bite of feed or take a drink of water by the light of the pilot. TABLE 7 .—Feed
consumption and mortality {trial 4) Number dead' to date 4 wks.
8 wks.
Lbs. feed to produce a pound of gain
7 5 5 14
34 20 17 22
3.5 2.9 3.0 3.0
No. started
2. Gas—no lights 3. Wood—lights 4. Wood—no lights
160 160 150 150
In 1939 four lots of poults were brooded, two under the gas burning brooders used the previous seasons and two under wood burning brooders which shed no incidental light. One pen under each brooder received all-night lights. Bronze and White Holland poults were used and progeny of different matings were distributed equally. The differences in mean weights were not significant when analysis of variance was applied. The differences between the males approached significance due to the low mean of lot 1.
SUMMARY
Management studies with turkey poults for four years, involving over 1,700 poults, show clearly that all-night lights do not increase the growth or feed consumption of the poults over that of poults receiving only normal daylight. In some cases lights may aid in preventing crowding and piling up but crowding may occur even with all-night lights. Careful management and close attention to the birds at night will prevent this bad habit from becoming established. Lights
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
1. 2. 3. 4.
cfcT mean (pounds)
Further analysis showed that several runty White Holland males in lot 1 were responsible while there were no differences betwen the Bronze or any other White Hollands. This is an illustration of the importance of large numbers in experimental animals as variable as turkeys if conclusions are to be valid. The viability and economy of gain are given in Table 7. Highest mortality was in pen 1 with lights but the differences in mortality were not significant when tested by x2- The higher mortality in pen 1 was largely due to crowding and piling up. This shows that all-night lights will not absolutely prevent crowding. The large feed consumption per pound of gain in lot 1 can probably be attributed to the higher mortality in that pen. The greatest loss occurred after the poults were four weeks of age and had already consumed considerable feed. Feed consumption was not adjusted for mortality.
336
T. T. MILBY AND R. B. THOMPSON
would not be justified unless they were very cheap. REFERENCES
Ballard, S. M., 1930. Uses of electric lights on growing chicks. Reliable Poultry Journal. 37 :406. Buckner, G. Davis, W. M. Insko, Jr., and J. Holmes Martin, 1934. Growth of White Leg-
horn chicks. Poult. Sci. 13:110-115. LeMasurier, H. E., and H. D. Branion, 1939. Some observations on the skeletal development of fowl to six weeks of age. Poult. Sci. 18:114-122. Zoratan, A. M., 1929. Studies on the effects on the growth of chicks of night' feeding with the aid of artificial illumination. Philippine Agr. 18:387-396. Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
HE opinion has frequently been expressed that the use of artificial light at night aids the growth of baby chicks. An example of this is given by Ballard (1930) in a popular news story. A commercial poultryman was using all-night lights on his broilers and claimed that the birds took more exercise and ate more feed, therefore, they grew faster. The first experimental evidence bearing on this problem is given by Zoratan (1929) who gave chicks an extra feeding (of grain) in the evening by using kerosene lanterns. He claimed that the chicks so fed grew faster, than the controls and feathered one week sooner with lower mortality. The death losses were high on all lots and based on present standards the growth was extremely poor. More recently, LeMasurier and Branion (1939) observed that chicks raised in battery brooders grew faster than comparable chicks raised on the floor. They attributed this better growth to the fact that the batteries were heated with electric bulbs which supplied sufficient light to allow the chicks to eat at night. In this connection the work of Buckner, Insko, and Martin (1934) might also be cited. In studying the growth of White Leghorn chickens one lot was raised in a colony brooder house and two lots were started in battery brooders. These brooders were heated with hot water and artificial light beyond normal daylight was not used. Up to six weeks of age the battery raised chicks were larger than the pen raised chicks.
There is also a common opinion that the use of a dim light at night helps to prevent crowding and piling up. Since turkey poults seem to be more prone to crowd than chicks, the use of all-night lights should be especially valuable in reducing early mortality. No experimental evidence has been brought to the attention of the authors to substantiate this opinion. EXPERIMENTAL
In 1936 an experiment was begun at this station to determine the effect of all-night lights on the growth, viability, and economy of gain of young turkeys. The growth period was divided into three periods, starting or brooding, growing, and finishing. The first year these periods were 9, 18, and 27 weeks; subsequently they were set at 8, 20, and 28 weeks. At the end of the brooding period each lot was further divided at random into three and the following lighting schedule was maintained for the starting, growing, and finishing periods respectively: 1. 2. 3. 4. 5. 6.
Lights Lights Lights No lights No lights No lights
Lights Lights No lights No lights No lights Lights
Lights No lights Lights No lights Lights No lights
Trial 1 In this experiment, begun April 16,1936, several varieties of turkeys were used, the majority of the poults being of the Bronze variety. Viability was recorded for all but growth was summarized only for the Bronze
[332]
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
T
333
T H E USE OF ALL-NIGHT LIGHTS FOR GROWING TURKEYS TABLE 1.—Growth of Bronze poults hatched April 16, 1936 {trial 1) 9 weeks
27 weeks
18 weeks
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. -birds
Mean weight (pounds)
47 42
2.17+.06 2.14+.06
43 46
6.89+.20 7.26+.20
46 42
15.0+.27 15.2+.28
36 45
1.77+.06 1.85+ .05
42 41
5.26+.17 5.33+.17
40 43
9.6+.16 10.3+ .15
Males: No lights Females:
since the turkeys of the other breeds were considerably smaller. Four hundred poults were divided into two groups so that the progeny of the different breeding pens were distributed uniformly. The poults given all-night lights were started in home-made electric battery brooders in which the heat and light was furnished by light bulbs. The group without artificial light was started in a gas-heated battery brooder. When the poults were two weeks of age they were transferred to similar 12 by 16 foot colony brooder houses heated by gas burning brooders. During the first three weeks 27 poults died in the all-night light group and 49 in the group without lights. Most of the poults that died in the latter group were smothered by piling up shortly after they were transferred from the battery to the floor. No crowding occurred in the all-night light group. Mortality after three weeks of age was about the same in both groups and was due largely to blackhead after the turkeys
were transferred to pens with outdoor runs. The mean weights of the Bronze turkeys at 9, 18, and 27 weeks of age together with their standard errors are given in Table 1. Only those turkeys that survived long enough to be sexed were included in the averages. The varying numbers are due to the varying combinations of the six groups. Analysis of variance indicated that there were no significant differences between the six groups nor between all groups with lights and those without at any age. In other words, all-night lights did not influence growth. Trial 2 In 1937 the trial was conducted essentially the same as in the previous year except that Bronze poults only were used and the periods were 8, 20, and 28 weeks. The same brooding equipment was used as in the previous year. The mortality was again high on the no lights group, 18.1 percent as compared to
TABLE 2.—Growth of Bronze poults hatched April 16, 1937 {trial 2) 20 weeks
8 weeks No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
57 24
1.S8+.03 1.33+.04
46 34
8.62+.14 8 . 4 2 + . 16
37 38
15.3+.21 15.0±.21
44 34
1.46+.03 1.24+.04
38 38
6.52+.12 6.33+.12
45 29
10.0+.09 10.0+.11
Males No lights Females: No lights
28 weeks
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
No lights
334
T. T. MILBY AND R. B. THOMPSON TABLE 3.—Pounds offeed required to produce a pound of gain {trial 2) 0to8 weeks Lights No lights.
9 to 20 21 to 28 Total to weeks 28 weeks weeks 7.4 7.4
5.0 4.7
1.3 2.2
5.2 5.6
weeks to 20 weeks, and more thereafter. The varying sex ratio in the groups may account for this difference. Trial 3 Because of the difficulty encountered in regulating the gas brooders used in the previous trials all poults were started on the floor in the third trial. Electric brooders of identical design were used. A change was made in the ration used for starting the poults with a considerable increase in the rate of growth. Otherwise the plan used in the previous trials was followed. Two hundred Bronze poults were started in each group. There were no significant differences in the growth, mortality, or feed consumption. The growth statistics are given in Table 4; mortality and feed statistics in Table S.
TABLE 4.—Growth of Bronze poults hatched April 8, 1938 {trial 3) 8 weeks
Males: Lights No lights Females: No lights
20 weeks
28 weeks
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
No. birds
Mean weight (pounds)
87 95
2.36+.04 2.41+.03
76 87
11.2+ .13 11.4+ .12
83 75
18.4+.23 18.9+.24
71 65
1.97+.03 1.99+.04
64 61
8.11+.10 8 . 1 8 + . 10
55 62
11.6+ .12 11.8+ .11
TABLE 5.—Feed consumption and mortality {trial 3) Pounds feed to produce 1 pound of gain
Number dead to date
Lights No lights. . .
4 wks.
8 wks.
0 to 8 wks.
9 to 20 wks.
21 to 28 wks.
Total
30 31
42 38
2.6 2.5
5.3 4.9
7.2 7.4
5.5 5.4
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
8.8 percent in the lights groups to four weeks of age and 51 percent as compared to 29.4 percent to eight weeks. While the poults were in the battery brooder considerable difficulty was encountered in regulating the temperature in the gas heated brooders and the poults were badly chilled. No difficulty was experienced in the electric brooders. The heavy mortality was probably due to the chilling. The statistics on growth are given in Table 2. The difference in weight at eight weeks of age is highly significant but none of the other differences are significant. The poor growth of the no light group as well as the high mortality may be due to the chilling. By the time the poults were 20 weeks of age they had made up this difference. Feed consumption is given in Table 3. After the poults were eight weeks of age the feed consumption is not greatly different. It is probable that there is an error in the feed for the first eight weeks since 1.3 pounds of feed per pound of gain is not reasonable. The group without lights consumed less feed per pound of gain from 8
33S
T H E USE OF ALL-NIGHT LIGHTS FOE GROWING TURKEYS
Trial 4 Although in two of three previous trials all-night lights had not benefited growth and the third trial was open to question it occurred to the authors that all brooders TABLE 6.—Mean weights at 8 weeks of age. Poults hatched April 22, 1939 {trial 4)
Gas—lights Gas—no lights... Wood—lights Wood—no lights.
9 9 mean (pounds)
2.02+.07 2.20±.06 2.22+.06 2.27+.06
1.78+.05 1.83+.05 1.94+.05 1.85+.05
used furnished some incidental light. In the case of the gas burning brooders the pilot flame and in case of the electric brooders the pilot light gave some illumination. Observation after dark indicated that in the pen without lights an occasional poult did eat a bite of feed or take a drink of water by the light of the pilot. TABLE 7 .—Feed
consumption and mortality {trial 4) Number dead' to date 4 wks.
8 wks.
Lbs. feed to produce a pound of gain
7 5 5 14
34 20 17 22
3.5 2.9 3.0 3.0
No. started
2. Gas—no lights 3. Wood—lights 4. Wood—no lights
160 160 150 150
In 1939 four lots of poults were brooded, two under the gas burning brooders used the previous seasons and two under wood burning brooders which shed no incidental light. One pen under each brooder received all-night lights. Bronze and White Holland poults were used and progeny of different matings were distributed equally. The differences in mean weights were not significant when analysis of variance was applied. The differences between the males approached significance due to the low mean of lot 1.
SUMMARY
Management studies with turkey poults for four years, involving over 1,700 poults, show clearly that all-night lights do not increase the growth or feed consumption of the poults over that of poults receiving only normal daylight. In some cases lights may aid in preventing crowding and piling up but crowding may occur even with all-night lights. Careful management and close attention to the birds at night will prevent this bad habit from becoming established. Lights
Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015
1. 2. 3. 4.
cfcT mean (pounds)
Further analysis showed that several runty White Holland males in lot 1 were responsible while there were no differences betwen the Bronze or any other White Hollands. This is an illustration of the importance of large numbers in experimental animals as variable as turkeys if conclusions are to be valid. The viability and economy of gain are given in Table 7. Highest mortality was in pen 1 with lights but the differences in mortality were not significant when tested by x2- The higher mortality in pen 1 was largely due to crowding and piling up. This shows that all-night lights will not absolutely prevent crowding. The large feed consumption per pound of gain in lot 1 can probably be attributed to the higher mortality in that pen. The greatest loss occurred after the poults were four weeks of age and had already consumed considerable feed. Feed consumption was not adjusted for mortality.
336
T. T. MILBY AND R. B. THOMPSON
would not be justified unless they were very cheap. REFERENCES
Ballard, S. M., 1930. Uses of electric lights on growing chicks. Reliable Poultry Journal. 37 :406. Buckner, G. Davis, W. M. Insko, Jr., and J. Holmes Martin, 1934. Growth of White Leg-
horn chicks. Poult. Sci. 13:110-115. LeMasurier, H. E., and H. D. Branion, 1939. Some observations on the skeletal development of fowl to six weeks of age. Poult. Sci. 18:114-122. Zoratan, A. M., 1929. Studies on the effects on the growth of chicks of night' feeding with the aid of artificial illumination. Philippine Agr. 18:387-396. Downloaded from http://ps.oxfordjournals.org/ at Library of Medical Center of Fudan University on May 10, 2015