BIBLIOGRAPHY CINDY RUTH B. ...
BIBLIOGRAPHY
CINDY RUTH B. BACASION. APRIL 2012. Effect of Intermittent Lighting
Program on the Performance of Broilers. Benguet State University, La Trinidad, Benguet.
Adviser: Marlene B Atinyao, Ph.D.
ABSTRACT
This study was conducted to determine the effect of intermittent lighting program
on the growth rate, feed intake, conversion efficiency, morbidity and mortality rates and
the return on investment in broilers.
A total of 120 21-day old broilers were randomly distributed to 3 lighting regimens
as follows: 23-hour light and 1-hour darkness as control, cycle of 45-minute light and 15-
minute darkness, and cycle of 15-minute light and 2-hour darkness.
The result of this study showed that intermittent light did not affect the final weight
of birds at 45 days of age, feed conversion ratio, feed cost per kilogram gain in weight and
dressing percentage. The average feed conversion ratio of broilers obtained in this study
was 1.407. Highly significant differences were observed in the feed intake and gain in
weight of birds exposed to longer light period. Birds exposed to 23-hour light and 1-hour
darkness had a higher daily feed intake (0.155kg) and daily gain in weight (0.042kg) than
birds exposed to 45-minute light and 15-minute darkness that had a daily feed intake of
0.128kg with a daily gain in weight of 0.0385kg and those exposed to 15-minute light and
2-hour darkness that had a daily feed intake of 0.127kg with a gain in weight of 0.0363kg.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
It is concluded that birds subjected to 23-hour light and 1-hour darkness (cycle for
24 hours) and birds subjected to 15-minute light and 2-hour darkness (cycle for 24 hours)
had the same performance thus subjecting birds to 45-minute light and 15-minute darkness
is recommended.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
INTRODUCTION
Rearing broiler chicks under continuous lighting conditions has been known for
many years that it would give a maximal early growth rate due to higher feed consumption.
However, there’s a continuous research dealing with the effects of different lighting
programs as part of the production programs.
Lighting programs in broiler production have evolved over the years, with success
in improving live performance. However, the relatively recent and rapid improvement in
broiler growth rate has renewed interest in lighting programs as an aid in restricting early
growth. Since withholding light is a mild form of feed restriction, lighting programs can
be applied during critical periods in the broiler grow out or limit or modify early growth
and then capture compensatory gain in the later part of the grow out (The Alabama Poultry
Engineering and Economics Newsletter, 2006).
Light enables the birds to eat continuously thus; it is believed to result in a
maximum growth rate. Darkness on the other hand helps to stimulate melatonin, vitamin
D3 and other hormone levels in the blood that improve the chick’s immune system and
tissue development (Animal Industry Branch, Manitoba Agriculture and Food, 2007).
Nonetheless basing from competent researches made by authorities, sufficient light
boosts and increase the activity of the birds. That which although fed by much and greater
feeds, the feed conversion ratio is still lower as compared to birds with longer dark periods
with less feed consumption that results to less energy consumption due to the lessen activity
of the birds.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
The study was conducted to find out if using intermittent or alternate on and off
lighting program was effective and productive or not. Result of this study not only benefit
farmers, but can serve as benchmark data for further studies on better lighting programs.
The study aimed to determine the effect of lighting programs on the growth
performance of broilers and to determine which lighting program promotes faster growth
and better performance of the broilers. Specifically, the study aimed to determine the effect
of intermittent lighting program on the growth rate, feed intake and conversion efficiency
of broilers; to determine morbidity and mortality rates in broilers subjected to intermittent
lighting program; and to determine effect of intermittent lighting program on the return on
investment in broiler production.
This study was conducted at Midas, Ohio, Ucab, Itogon, Benguet from November
to December, 2011.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
REVIEW OF LITERATURE
Some authorities have expressed the opinion that with continuous lighting, chicks
are able to eat continuously and thereby, grow at a faster rate. Studies have shown however
that although lighted birds consumed more feeds, it does not necessarily mean they would
weigh more than those on shorter light periods. Other authorities, on the other hand
maintain that young chicks need a good rest and a good rest is almost impossible in the
presence of lights (Fronda, 1972).
Aerts et al., (2000) as cited by Daghir, (2008) stated that the use of intermittent
light has been shown to increase feed consumption during the cooler part of the day.
Intermittent lighting had been shown to improve feed efficiency in the broilers and this
improvement can be due to the lower heat production during the dark period.
Turning the lights off is one best thing that you can do for the young meat-type
chickens. By giving birds short days and long nights from one week to three weeks of age,
it help maintain a healthy body and rapid growth rate. Long dark periods help stimulate
melatonin, vitamin D3 and other hormone levels in the blood that improves the chick’s
immune system and tissue development. Limiting the hour of light will slow growth
slightly, allowing the birds to develop strong hearts and bones needed to support rapid
growth later in the flocks. Turning the lights off when birds are young produces benefits
that can last in the flocks (Animal Industry Branch, Manitoba Agriculture and Food, 2007).
The technology of broiler production stipulates a 23-hour light regime (with half
an hour or an hour of darkness) in order to enhance feed intake and weight gain. The short
period of darkness is intended to get the broilers need to the absence of light that may occur
to possible power supply failure. The decrease of the light regimen resulted in a significant
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
decrease of the body weight. Broiler liveability increased in the groups with higher periods
of darkness mainly due to lower incidence of the sudden death syndrome (Parvu et al.,
2004).
Recent studies of Scheele et al., Gordon (1997) as cited by Parvu et al. (2004) have
shown that mortality and the incidence of feet diseases increased in the birds with longer
light regimens. It is an established fact that light influences the activity of the anterior
hypothesis and of the hormonal factors of growth.
There had been various lighting patterns tried like subjecting birds to alternate light
and darkness of varying length. Clegg and Sanford (1951) as cited by Patulot (1984)
observed heavier weight of broilers exposed to short periods alternate light and darkness.
Birds do not normally feed during the dark period but will do so if the photo period
is very short for instance 6 hours or less (Morris, 1967) cited by Appleby et al., (2004)
intermittent lighting patterns are gaining more increasing acceptance for commercial
rearing, particularly for broiler production, and birds respond by modifying their feeding
activity appropriately (Lewis et al., (1957) as cited by Appleby et al., (2004).
Bright lights also have various effects to the behaviors that are adverse for either
the owner or the birds. It increases the activity, and probably for this reason tends to
decrease growth (Cherry and Barwid, 1962) cited by Appleby et al., (2004) because
activity uses energy. It also increases aggression and feather pecking.
Dozier (2002) as cited by Basalong (2006) observed that increasing lighting
program decreased leg abnormalities and total mortality was also significantly reduced,
less respiratory lesion and better immunity to respiratory diseases than in poultry that were
exposed to constant light. The health of the bird was improved due to melatonin hormone
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
produced during the dark periods. Dozier noticed that low light intensity helped control
bird activity, thus, improving feed conversion. He further stated that broiler growers should
consider not only controlling the number of hours but as well as light intensity. He added
that lighting system and programs that is best for a particular company or producer depends
on the type of housing, the type of birds grown, climate and electricity.
According to the studies of Basalong (2006) and Macliing (2001) the final weight
of the birds were not affected by the light and dark periods.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
MATERIALS AND METHODS
The materials and equipment used in this study were the following: 120 21-day-old
cobb broiler chicks, feeds, antibiotics, vitamins and minerals, brooding rearing cages,
feeders, drinkers, electric wiring and sockets, 100-watt bulbs, weighing scale, cleaning
materials, black curtains, disinfectants, newspapers, automatic timer switchers, marking
pen and notebook.
Seven days before the arrival of the chicks, all equipment were cleaned and
disinfected. The brooding-rearing cages were divided to accommodate the three treatments
with four replicates. For treatments 1 and 2, sides of the cages were covered with plywood
except on the top which were covered with black curtains to ensure that no light penetrate
inside. For control treatment cages were all screen. Incandescent bulb was installed in each
cage to provide heat to the birds. For treatments 1 and 2, extra sockets for bulb covered
black were installed to provide heat during the dark period. It was switched on when the
lights were switched off. The floor was covered with newspaper to serve as receptacles
during the first two weeks of the experiment. Four hours before the arrival of chicks, lights
were switched on to attain uniform warmth inside the cages.
On the 21st day of age, the chicks were randomly distributed into three treatments
which were replicated four times with 10 birds per replicate, following the Completely
Randomized Design (CRD). The chicks were weighed individually to obtain their initial
weight. The treatments were as follows:
T0 - 23-hour light and 1- hour darkness (cycle for 24 hours)
T1 - 45-minute light and 15-minute darkness (cycle for 24 hours)
T2 - 15-minute light and 2-hour darkness (cycle for 24 hours)
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
For treatment 0, lights were switched off from 8 PM to 9 PM. For treatment 1, lights
were intermittently switched on for 45 minutes and then switched off for 15 minutes. For
treatment 2, lights were intermittently switched on for 15 minutes and then turned-off for
2 hours. This was a cycle throughout the day throughout the study. All the switching on
and off of lights were done by automatic timer switcher.
Ad libitum feeding was employed from the start until the end of the study. Feeders
were provided inside the cages during the rest of brooding period. The newspaper mats
were removed after 14 days of brooding.
Antibiotics, vitamins and minerals were added to the drinking water following the
prescribed dosage throughout the study. Chick booster was given to the chicks up to two
weeks of age and then gradually shifted to starter ration on the 15th day and to finisher
ration on the 31st day until the end of the study. Shifting of feeds were done by mixing 25%
of the new type of feed on the first day, 50% on the second day and 75% on the third day
so that on the fourth day, the birds were fed with new type of feed.
Data Gathered:
1. Initial weight of the broilers (kg). This was obtained by weighing the birds
individually at the start of the study which was on the 21st day of the broilers.
2. Final weight of the broilers (kg). This was obtained by weighing broilers at
the end of the study which was on the 45th day of age.
3. Feed offered (kg). This was the amount of feed given to the broilers in a day.
4. Feed left-over (kg). This was the amount feed left after a day of feeding.
5. Dressed weight (kg). This was the weight of the broilers after being dressed.
6. Number of sick birds. This was obtained by recording the number of birds
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
that got sick throughout the study.
7. Number of dead birds. This was obtained by recording the number of birds
that died throughout the study.
8. Feed cost. This was the purchase cost of feeds at the time of the study.
Data Computed:
1. Average gain in weight of broilers (kg). This was the taking difference between
the initial weight and the final weight.
2. Average feed intake of broilers (kg). This was obtained by taking the difference
between the feed offered and the feed refused divided by the number of days on trial.
3. Feed conversion ratio (FCR). This was obtained by dividing the total feed
intake by the total gain in weight.
4. Feed cost per kilogram gain in weight of broilers (Php). The cost to produce a
kilogram body weight was obtained by multiplying the feed conversion ratio by the cost of
1 kg feed.
5. Percentage mortality of the broilers (%). This was the number of dead birds
divided by the total population per treatment, and then multiplied by 100.
6. Percentage morbidity of the broilers (%). This was the number of sick birds
divided by the total population per treatment, and then multiplied by 100.
7. Return on investment (ROI). This was computed by taking the net income
divided by the total cost, then multiplied by 100.
Data were analyzed using the analysis of variance appropriate for CRD. Means
were compared using DMRT. The carcass data were analyzed using the covariance
analysis, with dressed weight as the covariate.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
RESULTS AND DISCUSSIONS
Mean Initial and Final Weight (kg)
The initial weight of the birds at 21 days of age is shown in Table 1. Statistical
analysis showed no significant differences in the initial weight of the birds between
treatments. This indicates that the birds were relatively uniform in weight at the start of the
study. The initial weight of birds ranges from 0.43kg to 0.45kg with an average of 0.44kg.
Mean final weight of broilers at the 45 days of age was also shown in Table 1.
Analysis of variance revealed no significant differences among treatment means. The final
weight of birds with 23-hour light and 1-darkness had 1.48 kg, birds with 45-minute light
and 15-minute darkness had 1.40 kg, and birds with 15-minute light and 2-hour darkness
had a 1.36 kg.
The observation on the final weight is same with the study of Basalong (2006) and
Macliing (2001) who reported that final weight of birds were not affected by the variation
in the length of intermittent light and dark period.
Table 1. Mean initial and final weights of broilers
TREATMENTS
INITIAL WEIGHT FINAL WEIGHT
AT 21 DAY
AT 45 DAY
(kg)
(kg)
23-hour light and 1-hour darkness
0.43a
1.48a
45-minute light and 15-minute darkness
0.44a
1.40a
15-minute light and 2-hour darkness
0.45a
1.36a
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
Mean Total and Average Gain in Weight
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
The total and average gain in weight of the birds from the 21 days of age to the 45
days of age is shown in Table 2. Statistical analysis revealed significant differences in the
total and average daily gain (ADG) in weight of the birds. The ADG of birds subjected to
23-hour light and 1-hour darkness of 0.0420 kg, those subjected to 45-minute light and 15-
minute darkness of 0.0385 is significantly higher than those subjected to 15-minute light
and 2-hour darkness of 0.0363kg.
The result study of this is the same with the statement of Fronda (1972), that with
such continuous lighting, the chicks are enabled to eat continuously and thereby, they grow
at a faster rate. Studies have shown however that although lighted birds consumed more
feeds, it does not necessarily mean they would weigh more than those on shorter light
periods
Table 2.Total and average gain in weight of birds from 21 days to 45 days of age
TREATMENTS
TOTAL GAIN AVERAGE DAILY
IN WEIGHT
GAIN IN WEIGHT
(kg)
(kg)
23-hour light and 1-hour darkness
3.875 a
0.0420 a
45-minute light and 15-minute darkness
3.2 ab
0.0385 ab
15-minute light and 2-hour darkness
3.171b
0.0363 b
Means with a not common letter(s) are not significantly different at 0.05 level of DMRT.
Mean Average Daily Feed Intake (kg)
Table 3 shows the average feed intake of the broilers from day 21 to day 45.
Analysis of variance revealed a highly significant difference in the feed intake of broilers
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Table 3. Total and average daily feed intake of broilers from day 21 to day 45
TREATMENT
TOTAL FEED AVERAGE DAILY
INTAKE FEED INTAKE
(kg)
(kg)
23-hour light and 1-hour darkness
3.88a
0.155 a
45-minute light and 15-minute darkness
3.2b
0.128 b
15-minute light and 2-hour darkness
3.71b
0.127 b
Means with a common letter(s) are not significantly different at 0.01 level of DMRT.
among treatments. Birds subjected to 45-minute light and 15-minute darkness had a total
feed intake (TFI) of 3.2kg with an average daily feed intake (ADFI) of 0.128 kg and birds
subjected to15-minute light and 2-hour darkness had an TFI of 3.71kg with an ADFI of
0.127 kg was significantly lower than the TFI (3.88kg) and ADFI (0.155kg) of birds
subjected to 23-hour light and 1-hour darkness.
This finding agrees with the observation of Parvu et al., where birds exposed to 23
hours light and 1 hour darkness had total feed intake (TFI) of 3.34 kg, those exposed to 8
cycles of 2 hours light and 1 hour darkness with an TFI of 2.94 kg; birds exposed to 6
cycles of 2 hours light and 2 hours darkness with an TFI of 2.90 kg and birds subjected to
12 hours light and 12 hours darkness had 2.20 kg feed intake with a duration of 49 days
that the shorter the period of light the lesser the feed intake.
This shows that light enables the birds to eat continuously. This was showed in the
high feed intake of birds with 23-hour light and 1-hour darkness.(Animal Industry Branch,
Manitoba Agriculture and Food, 2007).
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Feed Conversion Ratio (FCR.
Table 4 shows the feed conversion ratio (FCR) from day 21 to day 45. Analysis of
variance revealed that the feed conversion ratios of birds were not significantly different
between treatments. This indicates that FCR of birds exposed to 23-hour-light and one hour
darkness
of a 1.49, those exposed to 45-minute light and 15-minute darkness of 1.34
and those exposed to 15-minute light and 2-hour darkness of 1.39 feed conversion ratios
are comparable.
This however disagrees with the study of Ingram and Hatten where birds exposed
to 23 hours light and 1 hour darkness had an FCR of 1.96 and birds exposed to 12 hours
light and 12 hours darkness with an of 1.93. Birds exposed to 12 hours light and 12 hours
darkness was significantly lower than birds exposed to 23 hour light and 1 hour darkness
in the FCR. This contrast can be due to the variation in the length of light and dark periods
used in the study. Shorter dark period were used in this study.
Table 4. Mean feed conversion ratio of broilers from day 21 to day 45
TREATMENTS
FEED CONVERSION RATIO
23-hour light and 1-hour darkness
1.49a
45-minute light and 15- minute darkness
1.34a
15-minute light and 2-hour darkness
1.39a
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Feed Cost per Kilogram Gain in Weight (Php)
Table 5 shows the feed cost per kilogram gain in weight of birds. Analysis of
Table 5. Feed cost per kilogram gain in weight (Php)
TREATMENTS
FEED COST/KG GAIN IN WEIGHT
23-hour light and 1-hour darkness
34.86
45-minute light and 15-minute darkness
31.30
15-minute light and 2-hour darkness
32.64
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
variance revealed no significant differences among treatments. This indicates that there
were not differences in the feed cost among the treatments. Birds subjected to 23-hour light
and1-hour darkness had 34.86; birds exposed to 45-minute light and 15-minute darkness
had 31.30 and birds exposed to 15-minute light and 2-hour darkness had 32.64 feed cost
per kilograms. There were no significant differences because the feed conversions were
not significant among treatments.
Mortality and Morbidity of Birds
Mortality and morbidity of birds were not observed in the study. Providing vitamins
and minerals not only in the brooding period but until the 35th days of age could help why
mortality and morbidity are not observed in the study. And the weather and environment
could be a factor too.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Dressing Percentage
The dressing percentage is shown in Table 6. Analysis of variance shows no
significant differences between the dressing percentages of broilers. This indicates that the
dressing percentage of broilers was not significantly affected by intermittent light.
Table 6. Dressing percentage of 1.5 kg birds
TREATMENT
SLAUGHTER DRESSED DRESSING %
WEIGHT (KG) WEIGHT (KG)
23-hour light and 1-hour darkness
1.5
1.05
69.99
45-minute light and 15-minute darkness
1.5
1
66.67
15-minute light and 2-hour darkness
1.5
1
66.67
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
The average the dressing percentage of broilers is 67.78%. The dressed weight of
birds excluded the head, feet and entrails. This differ from the 69 dressing percentage of
Ibarra, may due on how the head was cut.
Return on Investment
The return on investment (ROI) of birds subjected to 23-hour light and 1-hour
darkness of -21.08% and those subjected to 45-minute light and 15-minute darkness of -
16.07 % was significantly lower than the ROI of birds subjected to 15-minute light and 2-
hour darkness of -4.93%. This is due to higher feed intake and electric consumption of
bird’s subjected to longer light periods, thus higher feed and electric costs.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Table 7. Return on investment(%)
TREATMENT
ROI (%)
23-hour light and 1-hour darkness
-31.47
45-minute light and 15-minute darkness
-28.20
15-minute light and 2 hour-darkness
-20.65
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
This study was conducted to determine the effect of intermittent lighting program
on the performance of broilers giving three treatments. Birds were subjected to 3 lighting
regimens as follows: 23 hour light and 1 hour darkness as control, cycle of 45 minutes light
and 15 minutes darkness, and cycle of 15 minutes light and 2 hours darkness.
Results showed that intermittent light did not affect the final weight of birds at 45
days of age, feed conversion ratio, feed cost per kilogram gain in weight and dressing
percentage. The average initial weight of birds at 21 days was 0.44 kg and the final weight
of birds at 45 days was 1.411 kg. The average daily gain was 0.04kg with an average feed
conversion ratio of 1.407. Feed cost to produce a kg gain in weight was 32.93 pesos and
the average dressing percentage was 67.78%. Highly significant differences were observed
in the feed intake and gain in weight of birds exposed to longer light period.
Daily gain in weight of birds exposed to 23-hour-light and one hour darkness
(0.0420) were significantly higher different on gain in weight with those on shorter light
periods on the final weight of birds were mot comparable among treatments. This shows
that as the birds are growing, birds with longer light were gaining more weight compared
with those of shorter light, but in the final weight they were not significantly different. This
result was affected by little differences on the initial weight of birds.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Conclusion
Result of this study showed that exposing broiler birds to intermittent light did not
affect the growth performance of broilers. However the performance of birds subjected to
23-hour light and 1-hour darkness (cycle for 24 hours) and birds subjected to 15-minute
light and 2-hour darkness (cycle for 24 hours) are almost the same.
Recommendation
Basing from the result of the study, 45-minute light and 15-minute darkness is
recommended.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
LITERATURE CITED
ANIMAL INDUSTRY BRANCH, MANITOBA, AGRICULTURE AND FOOD.2007.
Lighting Program for Small Roaster Flocks. ( www.gov.mb.ca)
APPLEBY, M.C, MENCH, J.A, and HUGHES,B.O. 2004. Poultry Behaviour and
Welfare. UK. CABI Publishing. Pp. 56
BASALONG, C.M 2006. Effect of lighting program on the performance of broiler,
Thesis. Benguet State University, College of Agriculture, La Trinidad, Benguet.
DAGHIR, N.J.2008. Poultry Production in the Hot Climate. 2nd Edition. Uk. CABI
Publishing. Pp. 251
FRONDA, F.M 1972. Poultry Science and Production. 2nd Edition. Manila. G.M.S
Publishing Corporation, Inc. Pp.100-101
INGRAM, D.R and HATTEN, L.F. 2000. Effect of light restriction on broiler
performance and specific body structure measurement. Poultry Science
Association, Inc.
MACLIING, E.G.2001. The effect of light and dark periods on the performance of
broiler. Thesis. Benguet State University, College of Agriculture, La Trinidad,
Benguet.
PARVU ET AL., 2004. Influence of the light program on the growth performance of
broiler. (www.ibna.ro/archival/Az%207_05_Parvu.pdf)
PATULOT, V.M.1984. Effect of the three lighting regiment on the growth and mortality
of commercial broiler chicks, Thesis. Benguet State University, College of
Agriculture, La Trinidad, Benguet.
THE ALABAMA POULTRY ENGINEERING AND ECONOMICS NEWSLETTER.
2006. Controlling light in broiler production.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
CINDY RUTH B. BACASION. APRIL 2012. Effect of Intermittent Lighting
Program on the Performance of Broilers. Benguet State University, La Trinidad, Benguet.
Adviser: Marlene B Atinyao, Ph.D.
ABSTRACT
This study was conducted to determine the effect of intermittent lighting program
on the growth rate, feed intake, conversion efficiency, morbidity and mortality rates and
the return on investment in broilers.
A total of 120 21-day old broilers were randomly distributed to 3 lighting regimens
as follows: 23-hour light and 1-hour darkness as control, cycle of 45-minute light and 15-
minute darkness, and cycle of 15-minute light and 2-hour darkness.
The result of this study showed that intermittent light did not affect the final weight
of birds at 45 days of age, feed conversion ratio, feed cost per kilogram gain in weight and
dressing percentage. The average feed conversion ratio of broilers obtained in this study
was 1.407. Highly significant differences were observed in the feed intake and gain in
weight of birds exposed to longer light period. Birds exposed to 23-hour light and 1-hour
darkness had a higher daily feed intake (0.155kg) and daily gain in weight (0.042kg) than
birds exposed to 45-minute light and 15-minute darkness that had a daily feed intake of
0.128kg with a daily gain in weight of 0.0385kg and those exposed to 15-minute light and
2-hour darkness that had a daily feed intake of 0.127kg with a gain in weight of 0.0363kg.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
It is concluded that birds subjected to 23-hour light and 1-hour darkness (cycle for
24 hours) and birds subjected to 15-minute light and 2-hour darkness (cycle for 24 hours)
had the same performance thus subjecting birds to 45-minute light and 15-minute darkness
is recommended.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
INTRODUCTION
Rearing broiler chicks under continuous lighting conditions has been known for
many years that it would give a maximal early growth rate due to higher feed consumption.
However, there’s a continuous research dealing with the effects of different lighting
programs as part of the production programs.
Lighting programs in broiler production have evolved over the years, with success
in improving live performance. However, the relatively recent and rapid improvement in
broiler growth rate has renewed interest in lighting programs as an aid in restricting early
growth. Since withholding light is a mild form of feed restriction, lighting programs can
be applied during critical periods in the broiler grow out or limit or modify early growth
and then capture compensatory gain in the later part of the grow out (The Alabama Poultry
Engineering and Economics Newsletter, 2006).
Light enables the birds to eat continuously thus; it is believed to result in a
maximum growth rate. Darkness on the other hand helps to stimulate melatonin, vitamin
D3 and other hormone levels in the blood that improve the chick’s immune system and
tissue development (Animal Industry Branch, Manitoba Agriculture and Food, 2007).
Nonetheless basing from competent researches made by authorities, sufficient light
boosts and increase the activity of the birds. That which although fed by much and greater
feeds, the feed conversion ratio is still lower as compared to birds with longer dark periods
with less feed consumption that results to less energy consumption due to the lessen activity
of the birds.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
The study was conducted to find out if using intermittent or alternate on and off
lighting program was effective and productive or not. Result of this study not only benefit
farmers, but can serve as benchmark data for further studies on better lighting programs.
The study aimed to determine the effect of lighting programs on the growth
performance of broilers and to determine which lighting program promotes faster growth
and better performance of the broilers. Specifically, the study aimed to determine the effect
of intermittent lighting program on the growth rate, feed intake and conversion efficiency
of broilers; to determine morbidity and mortality rates in broilers subjected to intermittent
lighting program; and to determine effect of intermittent lighting program on the return on
investment in broiler production.
This study was conducted at Midas, Ohio, Ucab, Itogon, Benguet from November
to December, 2011.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
REVIEW OF LITERATURE
Some authorities have expressed the opinion that with continuous lighting, chicks
are able to eat continuously and thereby, grow at a faster rate. Studies have shown however
that although lighted birds consumed more feeds, it does not necessarily mean they would
weigh more than those on shorter light periods. Other authorities, on the other hand
maintain that young chicks need a good rest and a good rest is almost impossible in the
presence of lights (Fronda, 1972).
Aerts et al., (2000) as cited by Daghir, (2008) stated that the use of intermittent
light has been shown to increase feed consumption during the cooler part of the day.
Intermittent lighting had been shown to improve feed efficiency in the broilers and this
improvement can be due to the lower heat production during the dark period.
Turning the lights off is one best thing that you can do for the young meat-type
chickens. By giving birds short days and long nights from one week to three weeks of age,
it help maintain a healthy body and rapid growth rate. Long dark periods help stimulate
melatonin, vitamin D3 and other hormone levels in the blood that improves the chick’s
immune system and tissue development. Limiting the hour of light will slow growth
slightly, allowing the birds to develop strong hearts and bones needed to support rapid
growth later in the flocks. Turning the lights off when birds are young produces benefits
that can last in the flocks (Animal Industry Branch, Manitoba Agriculture and Food, 2007).
The technology of broiler production stipulates a 23-hour light regime (with half
an hour or an hour of darkness) in order to enhance feed intake and weight gain. The short
period of darkness is intended to get the broilers need to the absence of light that may occur
to possible power supply failure. The decrease of the light regimen resulted in a significant
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
decrease of the body weight. Broiler liveability increased in the groups with higher periods
of darkness mainly due to lower incidence of the sudden death syndrome (Parvu et al.,
2004).
Recent studies of Scheele et al., Gordon (1997) as cited by Parvu et al. (2004) have
shown that mortality and the incidence of feet diseases increased in the birds with longer
light regimens. It is an established fact that light influences the activity of the anterior
hypothesis and of the hormonal factors of growth.
There had been various lighting patterns tried like subjecting birds to alternate light
and darkness of varying length. Clegg and Sanford (1951) as cited by Patulot (1984)
observed heavier weight of broilers exposed to short periods alternate light and darkness.
Birds do not normally feed during the dark period but will do so if the photo period
is very short for instance 6 hours or less (Morris, 1967) cited by Appleby et al., (2004)
intermittent lighting patterns are gaining more increasing acceptance for commercial
rearing, particularly for broiler production, and birds respond by modifying their feeding
activity appropriately (Lewis et al., (1957) as cited by Appleby et al., (2004).
Bright lights also have various effects to the behaviors that are adverse for either
the owner or the birds. It increases the activity, and probably for this reason tends to
decrease growth (Cherry and Barwid, 1962) cited by Appleby et al., (2004) because
activity uses energy. It also increases aggression and feather pecking.
Dozier (2002) as cited by Basalong (2006) observed that increasing lighting
program decreased leg abnormalities and total mortality was also significantly reduced,
less respiratory lesion and better immunity to respiratory diseases than in poultry that were
exposed to constant light. The health of the bird was improved due to melatonin hormone
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
produced during the dark periods. Dozier noticed that low light intensity helped control
bird activity, thus, improving feed conversion. He further stated that broiler growers should
consider not only controlling the number of hours but as well as light intensity. He added
that lighting system and programs that is best for a particular company or producer depends
on the type of housing, the type of birds grown, climate and electricity.
According to the studies of Basalong (2006) and Macliing (2001) the final weight
of the birds were not affected by the light and dark periods.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
MATERIALS AND METHODS
The materials and equipment used in this study were the following: 120 21-day-old
cobb broiler chicks, feeds, antibiotics, vitamins and minerals, brooding rearing cages,
feeders, drinkers, electric wiring and sockets, 100-watt bulbs, weighing scale, cleaning
materials, black curtains, disinfectants, newspapers, automatic timer switchers, marking
pen and notebook.
Seven days before the arrival of the chicks, all equipment were cleaned and
disinfected. The brooding-rearing cages were divided to accommodate the three treatments
with four replicates. For treatments 1 and 2, sides of the cages were covered with plywood
except on the top which were covered with black curtains to ensure that no light penetrate
inside. For control treatment cages were all screen. Incandescent bulb was installed in each
cage to provide heat to the birds. For treatments 1 and 2, extra sockets for bulb covered
black were installed to provide heat during the dark period. It was switched on when the
lights were switched off. The floor was covered with newspaper to serve as receptacles
during the first two weeks of the experiment. Four hours before the arrival of chicks, lights
were switched on to attain uniform warmth inside the cages.
On the 21st day of age, the chicks were randomly distributed into three treatments
which were replicated four times with 10 birds per replicate, following the Completely
Randomized Design (CRD). The chicks were weighed individually to obtain their initial
weight. The treatments were as follows:
T0 - 23-hour light and 1- hour darkness (cycle for 24 hours)
T1 - 45-minute light and 15-minute darkness (cycle for 24 hours)
T2 - 15-minute light and 2-hour darkness (cycle for 24 hours)
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
For treatment 0, lights were switched off from 8 PM to 9 PM. For treatment 1, lights
were intermittently switched on for 45 minutes and then switched off for 15 minutes. For
treatment 2, lights were intermittently switched on for 15 minutes and then turned-off for
2 hours. This was a cycle throughout the day throughout the study. All the switching on
and off of lights were done by automatic timer switcher.
Ad libitum feeding was employed from the start until the end of the study. Feeders
were provided inside the cages during the rest of brooding period. The newspaper mats
were removed after 14 days of brooding.
Antibiotics, vitamins and minerals were added to the drinking water following the
prescribed dosage throughout the study. Chick booster was given to the chicks up to two
weeks of age and then gradually shifted to starter ration on the 15th day and to finisher
ration on the 31st day until the end of the study. Shifting of feeds were done by mixing 25%
of the new type of feed on the first day, 50% on the second day and 75% on the third day
so that on the fourth day, the birds were fed with new type of feed.
Data Gathered:
1. Initial weight of the broilers (kg). This was obtained by weighing the birds
individually at the start of the study which was on the 21st day of the broilers.
2. Final weight of the broilers (kg). This was obtained by weighing broilers at
the end of the study which was on the 45th day of age.
3. Feed offered (kg). This was the amount of feed given to the broilers in a day.
4. Feed left-over (kg). This was the amount feed left after a day of feeding.
5. Dressed weight (kg). This was the weight of the broilers after being dressed.
6. Number of sick birds. This was obtained by recording the number of birds
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
that got sick throughout the study.
7. Number of dead birds. This was obtained by recording the number of birds
that died throughout the study.
8. Feed cost. This was the purchase cost of feeds at the time of the study.
Data Computed:
1. Average gain in weight of broilers (kg). This was the taking difference between
the initial weight and the final weight.
2. Average feed intake of broilers (kg). This was obtained by taking the difference
between the feed offered and the feed refused divided by the number of days on trial.
3. Feed conversion ratio (FCR). This was obtained by dividing the total feed
intake by the total gain in weight.
4. Feed cost per kilogram gain in weight of broilers (Php). The cost to produce a
kilogram body weight was obtained by multiplying the feed conversion ratio by the cost of
1 kg feed.
5. Percentage mortality of the broilers (%). This was the number of dead birds
divided by the total population per treatment, and then multiplied by 100.
6. Percentage morbidity of the broilers (%). This was the number of sick birds
divided by the total population per treatment, and then multiplied by 100.
7. Return on investment (ROI). This was computed by taking the net income
divided by the total cost, then multiplied by 100.
Data were analyzed using the analysis of variance appropriate for CRD. Means
were compared using DMRT. The carcass data were analyzed using the covariance
analysis, with dressed weight as the covariate.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
RESULTS AND DISCUSSIONS
Mean Initial and Final Weight (kg)
The initial weight of the birds at 21 days of age is shown in Table 1. Statistical
analysis showed no significant differences in the initial weight of the birds between
treatments. This indicates that the birds were relatively uniform in weight at the start of the
study. The initial weight of birds ranges from 0.43kg to 0.45kg with an average of 0.44kg.
Mean final weight of broilers at the 45 days of age was also shown in Table 1.
Analysis of variance revealed no significant differences among treatment means. The final
weight of birds with 23-hour light and 1-darkness had 1.48 kg, birds with 45-minute light
and 15-minute darkness had 1.40 kg, and birds with 15-minute light and 2-hour darkness
had a 1.36 kg.
The observation on the final weight is same with the study of Basalong (2006) and
Macliing (2001) who reported that final weight of birds were not affected by the variation
in the length of intermittent light and dark period.
Table 1. Mean initial and final weights of broilers
TREATMENTS
INITIAL WEIGHT FINAL WEIGHT
AT 21 DAY
AT 45 DAY
(kg)
(kg)
23-hour light and 1-hour darkness
0.43a
1.48a
45-minute light and 15-minute darkness
0.44a
1.40a
15-minute light and 2-hour darkness
0.45a
1.36a
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
Mean Total and Average Gain in Weight
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
The total and average gain in weight of the birds from the 21 days of age to the 45
days of age is shown in Table 2. Statistical analysis revealed significant differences in the
total and average daily gain (ADG) in weight of the birds. The ADG of birds subjected to
23-hour light and 1-hour darkness of 0.0420 kg, those subjected to 45-minute light and 15-
minute darkness of 0.0385 is significantly higher than those subjected to 15-minute light
and 2-hour darkness of 0.0363kg.
The result study of this is the same with the statement of Fronda (1972), that with
such continuous lighting, the chicks are enabled to eat continuously and thereby, they grow
at a faster rate. Studies have shown however that although lighted birds consumed more
feeds, it does not necessarily mean they would weigh more than those on shorter light
periods
Table 2.Total and average gain in weight of birds from 21 days to 45 days of age
TREATMENTS
TOTAL GAIN AVERAGE DAILY
IN WEIGHT
GAIN IN WEIGHT
(kg)
(kg)
23-hour light and 1-hour darkness
3.875 a
0.0420 a
45-minute light and 15-minute darkness
3.2 ab
0.0385 ab
15-minute light and 2-hour darkness
3.171b
0.0363 b
Means with a not common letter(s) are not significantly different at 0.05 level of DMRT.
Mean Average Daily Feed Intake (kg)
Table 3 shows the average feed intake of the broilers from day 21 to day 45.
Analysis of variance revealed a highly significant difference in the feed intake of broilers
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Table 3. Total and average daily feed intake of broilers from day 21 to day 45
TREATMENT
TOTAL FEED AVERAGE DAILY
INTAKE FEED INTAKE
(kg)
(kg)
23-hour light and 1-hour darkness
3.88a
0.155 a
45-minute light and 15-minute darkness
3.2b
0.128 b
15-minute light and 2-hour darkness
3.71b
0.127 b
Means with a common letter(s) are not significantly different at 0.01 level of DMRT.
among treatments. Birds subjected to 45-minute light and 15-minute darkness had a total
feed intake (TFI) of 3.2kg with an average daily feed intake (ADFI) of 0.128 kg and birds
subjected to15-minute light and 2-hour darkness had an TFI of 3.71kg with an ADFI of
0.127 kg was significantly lower than the TFI (3.88kg) and ADFI (0.155kg) of birds
subjected to 23-hour light and 1-hour darkness.
This finding agrees with the observation of Parvu et al., where birds exposed to 23
hours light and 1 hour darkness had total feed intake (TFI) of 3.34 kg, those exposed to 8
cycles of 2 hours light and 1 hour darkness with an TFI of 2.94 kg; birds exposed to 6
cycles of 2 hours light and 2 hours darkness with an TFI of 2.90 kg and birds subjected to
12 hours light and 12 hours darkness had 2.20 kg feed intake with a duration of 49 days
that the shorter the period of light the lesser the feed intake.
This shows that light enables the birds to eat continuously. This was showed in the
high feed intake of birds with 23-hour light and 1-hour darkness.(Animal Industry Branch,
Manitoba Agriculture and Food, 2007).
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Feed Conversion Ratio (FCR.
Table 4 shows the feed conversion ratio (FCR) from day 21 to day 45. Analysis of
variance revealed that the feed conversion ratios of birds were not significantly different
between treatments. This indicates that FCR of birds exposed to 23-hour-light and one hour
darkness
of a 1.49, those exposed to 45-minute light and 15-minute darkness of 1.34
and those exposed to 15-minute light and 2-hour darkness of 1.39 feed conversion ratios
are comparable.
This however disagrees with the study of Ingram and Hatten where birds exposed
to 23 hours light and 1 hour darkness had an FCR of 1.96 and birds exposed to 12 hours
light and 12 hours darkness with an of 1.93. Birds exposed to 12 hours light and 12 hours
darkness was significantly lower than birds exposed to 23 hour light and 1 hour darkness
in the FCR. This contrast can be due to the variation in the length of light and dark periods
used in the study. Shorter dark period were used in this study.
Table 4. Mean feed conversion ratio of broilers from day 21 to day 45
TREATMENTS
FEED CONVERSION RATIO
23-hour light and 1-hour darkness
1.49a
45-minute light and 15- minute darkness
1.34a
15-minute light and 2-hour darkness
1.39a
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Feed Cost per Kilogram Gain in Weight (Php)
Table 5 shows the feed cost per kilogram gain in weight of birds. Analysis of
Table 5. Feed cost per kilogram gain in weight (Php)
TREATMENTS
FEED COST/KG GAIN IN WEIGHT
23-hour light and 1-hour darkness
34.86
45-minute light and 15-minute darkness
31.30
15-minute light and 2-hour darkness
32.64
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
variance revealed no significant differences among treatments. This indicates that there
were not differences in the feed cost among the treatments. Birds subjected to 23-hour light
and1-hour darkness had 34.86; birds exposed to 45-minute light and 15-minute darkness
had 31.30 and birds exposed to 15-minute light and 2-hour darkness had 32.64 feed cost
per kilograms. There were no significant differences because the feed conversions were
not significant among treatments.
Mortality and Morbidity of Birds
Mortality and morbidity of birds were not observed in the study. Providing vitamins
and minerals not only in the brooding period but until the 35th days of age could help why
mortality and morbidity are not observed in the study. And the weather and environment
could be a factor too.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Dressing Percentage
The dressing percentage is shown in Table 6. Analysis of variance shows no
significant differences between the dressing percentages of broilers. This indicates that the
dressing percentage of broilers was not significantly affected by intermittent light.
Table 6. Dressing percentage of 1.5 kg birds
TREATMENT
SLAUGHTER DRESSED DRESSING %
WEIGHT (KG) WEIGHT (KG)
23-hour light and 1-hour darkness
1.5
1.05
69.99
45-minute light and 15-minute darkness
1.5
1
66.67
15-minute light and 2-hour darkness
1.5
1
66.67
Means with a common letter(s) are not significantly different at 0.05 level of DMRT.
The average the dressing percentage of broilers is 67.78%. The dressed weight of
birds excluded the head, feet and entrails. This differ from the 69 dressing percentage of
Ibarra, may due on how the head was cut.
Return on Investment
The return on investment (ROI) of birds subjected to 23-hour light and 1-hour
darkness of -21.08% and those subjected to 45-minute light and 15-minute darkness of -
16.07 % was significantly lower than the ROI of birds subjected to 15-minute light and 2-
hour darkness of -4.93%. This is due to higher feed intake and electric consumption of
bird’s subjected to longer light periods, thus higher feed and electric costs.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Table 7. Return on investment(%)
TREATMENT
ROI (%)
23-hour light and 1-hour darkness
-31.47
45-minute light and 15-minute darkness
-28.20
15-minute light and 2 hour-darkness
-20.65
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
SUMMARY, CONCLUSION AND RECOMMENDATION
Summary
This study was conducted to determine the effect of intermittent lighting program
on the performance of broilers giving three treatments. Birds were subjected to 3 lighting
regimens as follows: 23 hour light and 1 hour darkness as control, cycle of 45 minutes light
and 15 minutes darkness, and cycle of 15 minutes light and 2 hours darkness.
Results showed that intermittent light did not affect the final weight of birds at 45
days of age, feed conversion ratio, feed cost per kilogram gain in weight and dressing
percentage. The average initial weight of birds at 21 days was 0.44 kg and the final weight
of birds at 45 days was 1.411 kg. The average daily gain was 0.04kg with an average feed
conversion ratio of 1.407. Feed cost to produce a kg gain in weight was 32.93 pesos and
the average dressing percentage was 67.78%. Highly significant differences were observed
in the feed intake and gain in weight of birds exposed to longer light period.
Daily gain in weight of birds exposed to 23-hour-light and one hour darkness
(0.0420) were significantly higher different on gain in weight with those on shorter light
periods on the final weight of birds were mot comparable among treatments. This shows
that as the birds are growing, birds with longer light were gaining more weight compared
with those of shorter light, but in the final weight they were not significantly different. This
result was affected by little differences on the initial weight of birds.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
Conclusion
Result of this study showed that exposing broiler birds to intermittent light did not
affect the growth performance of broilers. However the performance of birds subjected to
23-hour light and 1-hour darkness (cycle for 24 hours) and birds subjected to 15-minute
light and 2-hour darkness (cycle for 24 hours) are almost the same.
Recommendation
Basing from the result of the study, 45-minute light and 15-minute darkness is
recommended.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012
LITERATURE CITED
ANIMAL INDUSTRY BRANCH, MANITOBA, AGRICULTURE AND FOOD.2007.
Lighting Program for Small Roaster Flocks. ( www.gov.mb.ca)
APPLEBY, M.C, MENCH, J.A, and HUGHES,B.O. 2004. Poultry Behaviour and
Welfare. UK. CABI Publishing. Pp. 56
BASALONG, C.M 2006. Effect of lighting program on the performance of broiler,
Thesis. Benguet State University, College of Agriculture, La Trinidad, Benguet.
DAGHIR, N.J.2008. Poultry Production in the Hot Climate. 2nd Edition. Uk. CABI
Publishing. Pp. 251
FRONDA, F.M 1972. Poultry Science and Production. 2nd Edition. Manila. G.M.S
Publishing Corporation, Inc. Pp.100-101
INGRAM, D.R and HATTEN, L.F. 2000. Effect of light restriction on broiler
performance and specific body structure measurement. Poultry Science
Association, Inc.
MACLIING, E.G.2001. The effect of light and dark periods on the performance of
broiler. Thesis. Benguet State University, College of Agriculture, La Trinidad,
Benguet.
PARVU ET AL., 2004. Influence of the light program on the growth performance of
broiler. (www.ibna.ro/archival/Az%207_05_Parvu.pdf)
PATULOT, V.M.1984. Effect of the three lighting regiment on the growth and mortality
of commercial broiler chicks, Thesis. Benguet State University, College of
Agriculture, La Trinidad, Benguet.
THE ALABAMA POULTRY ENGINEERING AND ECONOMICS NEWSLETTER.
2006. Controlling light in broiler production.
Effect of Intermittent Lighting Program on the Performance of Broilers
CINDY RUTH B. BACASION. APRIL 2012