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Effects of high temperature on production in layer chickens supplemented with vitamins C and E(Efectos de la alta temperatura sobre la producción en gallinas ponedoras suplementadas con vitaminas C y E)

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-tocopherol acetate/kg of diet (Group Vit C + E). Results. Egg/bird were higher (p<0.05) in all treatment groups when compared to control group, but p value was highly significant in vitamin E treated group. Likewise, the laying index was different (p<0.05) in all treatment groups when compared to control, and P value was highly significant in vitamin E treated group. Although, viability was not affected by vitamin C, vitamin E and vitamin C+E groups when compared to control (p>0.05). However, feed consumption and conversion were different (p<0.05) in treatment groups when compared to control group. Conclusions. Dietary supplementation with 150 mg vitamin C and/or 150 mg vitamin E increased production performance in heat stressed layer chickens.
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Rev.MVZ Córdoba 16(1):2283-2291, 2011. 2283
ORIGINAL
Effects of high temperature on production in layer
chickens supplemented with vitamins C and E
Efectos de la alta temperatura sobre la producción en gallinas
ponedoras suplementadas con vitaminas C y E
1 1 1Joachim Ajakaiye J, * M.Sc, Alcides Pérez B, Ph.D, Angel Mollineda T, B.Sc.
1Universidad Central “Martha Abreu” de Las Villas. Faculty of Agricultural Sciences. Department of
Pathophysiology. Carretera a Camajuaní Km 5½. Santa Clara, Villa Clara. Cuba. *Correspondence:
joachim@uclv.edu.cu
Recibido: Noviembre de 2009; Aceptado: Octubre de 2010.
ABSTRACT
Objetive. To determine the effects of high temperature, the high humidity and the index on
production performance in layer chickens supplemented with vitamins C and E. Materials
and methods. The experiment was carried out from July 14th to August 15th. A total
of 720 L33 layer chickens, 39 weeks old, were divided at random into four groups
(180 birds/group), by replicates (n=4): Control Group) was fed with a basal diet and
treatment groups were fed with the basal diet supplemented with either 150 mg of
l-ascorbic acid/g of diet (Group Vit. C) or 150 mg of dl-α-tocopherol acetate /kg, of diet
(Group Vit. E), and 150 mg of l-ascorbic acid /kg of diet plus 150 mg of dl-α-tocopherol
acetate/kg of diet (Group Vit C + E). Results. Egg/bird were higher (p<0.05) in all
treatment groups when compared to control group, but p value was highly signifcant in
vitamin E treated group. Likewise, the laying index was different (p<0.05) in all treatment
groups when compared to control, and P value was highly signifcant in vitamin E treated
group. Although, viability was not affected by vitamin C, vitamin E and vitamin C+E groups
when compared to control (p>0.05). However, feed consumption and conversion were
different (p<0.05) in treatment groups when compared to control group. Conclusions.
Dietary supplementation with 150 mg vitamin C and/or 150 mg vitamin E increased
production performance in heat stressed layer chickens.
Key words: Layer chickens, animal feed, vitamin C, vitamin E, eggs production. (Sources:
DeCs, AIMS, IEDCYT).
2283REVISTA MVZ CÓRDOBA • Volumen 16(1), Enero - Abril 20112284
RESUMEN
Objetivo. Investigar los efectos de la alta temperatura y humedad relativa y su índice
sobre el rendimiento productivo en las gallinas ponedoras suplementada con las vitaminas
C y E. Materiales y métodos. Se realizó el experimento desde 14 de Julio a 15 de Agosto.
720 gallinas ponedoras L33, y de 39 semanas de edad, fueron dividas en cuatro grupos de 180
aves. Se suministró un grupo con dieta basal (Control) y los grupos de tratamientos fueron
suministrados con dieta basal y suplementada con 150 mg de acido l-ascórbico/kg de dieta (grupo
vitamina C), 150 mg de acetato dl- α-tocoferol/kg de dieta (grupo vitamina E), mientras el último
grupo, se suministró 150 mg de acido l-ascórbico/kg de dieta mas 150 mg de acetato
dl-α-tocoferol/kg de dieta (grupo vitamina C+E). Resultados. Huevo/ave fueron
signifcativamente (p<0.05) mayor en todos los grupos tratados en comparación con
el control, pero el p fue más alta en el grupo tratado con vitamina E. De mismo
modo se observó una diferencia (p<0.05) signifcativa en el índice de postura en todos los
grupos tratados en comparación con el control. Aunque la viabilidad no fue afectada en
todos los grupos. Sin embargo, el consumo y la conversión alimentaria fueron diferentes
(p<0.05) signifcativamente en todos los grupos tratados en comparación con el control.
Conclusiones. La suplementacion dietética de 150 mg de vitamina C y/o 150 mg de
vitamina E aumentó el rendimiento productivo en las gallinas ponedoras sometidas a estrés
calórico.
Palabras clave: Gallinas ponedoras, alimentación animal, vitamina C, vitamina E,
producción de huevos. (Fuentes: DeCs, AIMS, IEDCYT).
INTRODUCTION
the tropical regions ranges between 18-In hot climates, periods of high
24 Holik (3). Maintaining a constant body temperatures have a negative effect on
temperature is not a problem when air the health and performance of domestic is at least 10-15 degrees less animals. Poultry farming is no exception
than body temperature. But air movement and the effect of stress caused by elevated
is critical. A bird can only give off heat to temperatures can result in heavy economic
its environment if the temperature of that losses from increased mortality and reduced
enis cooler than the bird. If heat productivity (1). For birds to perform at
produced by the birds is not moved away their optimum capacity they need to among
from them and out of the poultry house other factors to be in homeostasis with their
quickly, it will be more diffcult for them to environment through the maintenance
avoid heat stress (2). of thermobalance. Thermobalance is the
equilibrium between the heat produced
The changes in the biomass as result of the and the heat given out by living organism,
continuous global warming has a deleterious and this is at its maximal physiological
effect on domestic animals in general, and level within the thermoneutral range of
birds in particular. Ambient temperature any given specie. Birds, like mammals
(AT) above 25 is stressful for birds, but are homoeothermic, they produce heat
more stressful is the fuctuations caused to maintain a relatively constant body
by this environmental thermal changes, temperature and may permit certain
especially when it is accompanied by high variations within their temperature range
relative humidity (RH), as this unleash without signifcant perturbation (1).
various pathophysiological response in
birds (4,5). Furthermore, it has been Normally, the chicken’s body temperature
demonstrated that this response induces is 41.5°C, but will fuctuate somewhat
heat stress in chickens, and thus lead to depending upon the temperature of its
disturbance in production (6). environment (2), while the established
thermoneutral zone for birds reared in 2285Ajakaiye - Effects of high temperature on production in layer chickens
The free radicals generated as result of accompanied by a range of RH, which can
high AT and RH, overtax the anti-oxidant markedly affect the degree of heat stress
system of the animal and thus reduce their experienced by the bird (12). De Basilio et
viability. The large quantity of free radicals al (13) observed that with an AT between
thus liberated, initiate lipid peroxidation 38 to 40ºC and RH between 50 and 55%,
in cytomembranes Altan et al (7), chickens RT could be elevated to between
thereby, causing damage at the cell level 45 to 48°C leading to death by heat wave
Ramnath et al (8). During heat stress, the or acute stress with subsequent decrease in
environmental parameters of AT and RH in production effciency and economic gains.
general and temperature humidity index However, it was Tao and Xin (9) for the
(THI) in particular, have been reported to frst time that adapted THI for a function in
be an invaluable tool in the presumptive poultry using wind speed as a variable, and
diagnosis of the animal state of health, called this index; Temperature-Humidity-
and is also relevant in evaluating the Velocity Index (THVI, Table 1). They also
adaptability of the animal (9,10). established several stages of thermal
comfort values such as: normal ≤ 70, alert
Environmental fuctuations as a result of from 70 to 75, danger from 76 to 81, and
variation in AT below or above the thermal emergency ≥ than 82, based on the bird’s
comfort zone has been reported to be body temperature variation, based on the
a important element in the evaluation of following mathematical model according to
the negative effects of stress factors that Tao and Xin (9):
affects the organism (11). Altan et al (7)
reported that high AT and RH, increases THVI = (0.85 × DBT + 0.15 × WBT) ×
heat stress and are responsible for the V-0.058
increase in rectal/body temperature (RT). Where: THI = Temperature, Relative Humidity
Although a great deal of research has been Index and Air Velocity;
done concerning the responses of poultry DBT = Dry bulb temperature (°C);
to high ambient temperatures, the role that WBT = Wet bulb temper(°C).
RH play on intensifying or modifying these V = Air velocity.
responses has received little attention and Thus, 70 were established as a standard
particularly, air velocity. threshold value for THVI in poultry.
Relative humidity is rarely included as an Furthermore, De Moraes et al (14)
experimental variable or even measured reported that assessing the impact of
for information purposes. Such information specifc climate on livestock performance
is important because in poultry-producing is a diffcult task. Superfcial general
regions, high temperatures can often be analysis of impacts can be based on the
Table 1. Temperature and humidity index values related to heat stress safety.
Source: (USDC-ESSA, 1970) as modifed by (9).REVISTA MVZ CÓRDOBA • Volumen 16(1), Enero - Abril 20112286
animal response. However, combining the 327.2 cm, with an average air velocity of
relationship between livestock performance 3.15 m/s.
and the thermal environment is needed for
more precise assessment, and to provide Experimental birds. A total of 720 and 39
adequate quantitative and qualitative weeks old commercial L33 layer chickens,
performance evaluation. Researchers have were used as subjects for the experiment.
tried to mitigate the effect of heat stress The birds were divided in completely
by changing the environment and diets randomized design into four groups of 180
of laying chickens. Though environmental each, and each group was further divided
approach through modifcation of housing into four replicates of 45 birds. One group
is the best option for optimal performance, was fed with basal diet (Control Group)
it is nevertheless highly capital intensive, and treatment groups were fed with the
thereby making nutritional strategy a viable basal diet supplemented with either 150 mg
alternative. Nutritional strduring of l-ascorbic acid /kg of diet (Vit. C group),
heat period is based on diets balancing in 150 mg of α-dl-tocopherol acetate /kg of
order to cover the needs of stressed birds diet (Vit. E group), while the last group was
for ideal amino acids (protein), energy supplemented with 150 mg of l-ascorbic acid
and electrolytes (12,15). For this purpose, /kg of diet plus 150 mg of α-dl-tocopherol
vitamin C and vitamin E are used in the acetate/kg of diet (Vit C + E group).
poultry diet because of their anti-oxidant Vitamin C and vitamin E used were from
properties in the neutralization of the free a commercial company (VMD, n.v./s.a,
radicals generated during heat stress (8). Arendonk, Belgium).
Though poultry are renal synthesizers The birds received a basal diet of 110 g/
of vitamin C, but its quantity becomes bird/day, and water ad libitum. Feed
insuffcient during heat stress as a result constituents and bromatological analysis
of increased rate of usage in combating of the basal diet are shown in table 2.
the free radicals thus generated. On the The basal diet contained 2850 kcal/kg
other hand vitamin E has been reported metabolic energy (ME) and 20.1% crude
in the participation of the supply of egg protein (CP), 4.0% Ca, 0.60% P and
precursors in plasma, while at the same 12.6% ash. This diet exceed slightly the
time decreasing serum ACTH concentration
(16). Furthermore, Sahin et al (16) Table 2. Composition and bromatological analysis of
observed that dietary supplementation of diet given during the study period.
vitamin E increased fertility and layability
in layer chickens, while it caused reduction
in the process of lipid peroxidation. The aim
of this study therefore, was to investigate
the possible benefcial effects of dietary
vitamin C and vitamin E supplementation
on production performance in laying
chickens subjected to acute and chronic
heat stress.
MATERIAL AND METHODS
Experimental site. The study was
performed at the poultry production unit
of “Las casas II”, located at 5½ Km along
Santa Clara and Camjauni highway in the
province of Villa Clara; it is located between
22°53´ N and 82°02´ W, with an altitude
between 90-100 meters above sea level.
Total precipitation during this period was Source: UEB feed factory, Min. of Agriculture, Villa Clara (2009).Ajakaiye - Effects of high temperature on production in layer chickens 2287
nutrient requirements recommended by Table 4. Wet bulb temperature inside and
the standing committee on the scientifc outside the pen during the study
evaluation of dietary reference intakes of period.
the National Research Council (17).
Experimental procedures. The AT and
HR were measured daily using a standard
thermometer (Harris, England) with a 42
calibration and a standard hygrometer
(Harris, England) with a 50 calibration. All
production parameters measured during
this period were also carried out daily.
Mean values with different superscripts alphabets along the
same row are signifcantly (p<0.05) different.Statistical analyses. The PC STATISTICA
8.0 package was used and data were
analyzed by One-way Anova through the 25.9 inside and outside the pen house,
general-linear-models procedure of the respectively. In addition, the maximum
Statistical Analysis System. Means were temperature values recorded for inside and
compared by Duncan’s post-hoc test outside the pen were 30.3°C and 31.7°C,
(p<0.05) (18). respectively at 3.00 pm (p<0.05). There was
no signifcant difference in the overall WBT
between inside and outside the pen house
(p>0.05). The minimum THVI value recorded RESULTS
was 77.8, at 6.00 pm, and the maximum
value was 93.5 at 12.00 noon (Table 5).Dry bulb temperature and WBT data are
shown in tables 3 and 4. There were no
difference (p>0.05) in the overall average Table 5. Temperature, relative humidity and
DBT inside and outside the pen, even air velocity index during the study
though the dry-bulb showed a minimum period.
temperature of 27.7°C inside and outside
the pen house at 6.00 pm, the maximum
temperature inside was 33.3°C and outside
was 35.1°C at 3.00 pm. There was a
signifcant difference DBT outside and inside
the pen, between 12-3 pm (p<0.05). Even
though, the WBT showed minimum values
of 26.3°C and 25.9°C inside and outside
the pen house, respectively. Similarly, the
WBT showed minimum values of 26.3 and
The highest range value of 14.6 during the
experimental period was recorded at 3.00 Table 3. Dry bulb temperature inside and
pm. The average THVI value was 85.5 during outside the pen during the study
the same period. Production performance period.
parameters are presented in table 6. Egg/
bird were higher in all treatment group when
compared to control (p<0.05), but p value
was particularly highest in vitamin E treated
group. Overall egg/bird increased consistently
in all groups from highly signifcant difference
(p<0.01) in week 1 to very highly signifcant
(p<0.001) difference from weeks 2 to 4.
Likewise, the laying index was signifcant
in all treatment groups when compared Mean values with different superscripts alphabets along the
to control (p<0.05), and p value was same row are signifcantly (p<0.05) different.REVISTA MVZ CÓRDOBA • Volumen 16(1), Enero - Abril 20112288
particularly highest in vitamin E treated DISCUSSION
group. Overall laying index increased
consistently in all groups from highly The dry and wet-bulb temperatures, for
signifcant difference (p<0.01) in week 1 inside and outside the pen house were
to very highly signifcant difference from higher than the recommended thermo
weeks 2 to 4 (p<0.001). Feed consumption neutral zone of 18-24°C, that Holik (3)
and conversion were signifcantly different established for poultry in the tropical
in vitamin C, vitamin E and vitamin C+E regions. Likewise, the THI in this experiment
supplemented groups when compared to were outside the normal zone of ≤ 70 that
control group (p<0.05). Tao and Xin (9) established for poultry. The
response of chickens at high temperatures
Viability/mortality was not affected by differs with different relative humidity. It
vitamin C, vitamin E and vitamin C+E has been reported that ature
supplemented groups when compared to accompanied by high humidity is more
control (p>0.05). detrimental to layer performance than
Table 6. Production performance and its indices during the study period (n=80).
Mean values with different superscripts alphabets along the same row are signifcantly different. Level of signifcance:
*=p<0.05. **=p<0.01. ***=p<0.001.Ajakaiye - Effects of high temperature on production in layer chickens 2289
high temperature with low humidity. At oxidized form of vitamin E to its stable
the same time, constant high temperature form through a non-enzymatic reaction.
of 30-32°C is more deleterious to birds Similarly, vitamin E has also been
than cyclic or alternating temperatures of demonstrated to be an antioxidant that
30-32°C by day and 25°C by night. Feed scavenges the free radicals generated in
conversion in broilers is subject to marked cell membranes that participates in tissular
fuctuations because of seasonal as well as degeneration (20).
ambient temperature changes.
The vitamin participates in a tripartite
All studies indicate that high temperatures interaction together with selenium, an
reduce the effciency of utilizing feed integral chemical complex of the enzyme
energy for productive purposes. Layers not GSHPx as protagonists, while the poly
only eat less at high temperature, but also unsaturated fatty acids serve as the
produce less per unit of intake, especially antagonist (GSHPx, 21). The synergic
at temperatures above 30°C. The single effects between these two vitamins are
or combined dietary supplementation with particularly effcient for reducing production
vitamin C and vitamin E of laying chickens of reactive oxygen species. Because radical
exposed to heat stress signifcantly reactions are exergonic, they contribute to
improved production performances of feed the failure of thermoregulatory process in
consumption, conversion and egg/bird/day. hyperthermia observed during heat stress.
Supplementation, of vitamin E alone into Consequently, dietary supplementation
diets appeared to be more benefcial for of birds with vitamin C, vitamin E or a
laying hens during heat stress, probably, combination of these two anti-oxidant
due to its concurrent function as fertility compounds would attenuate the deleterious
factor (16). heat-induced-oxidative stress. Vitamin
E supplementation of diets containing
Vitamin C has been demonstrated to be high amounts of polyunsaturated fatty
a powerful antioxidant that acts through acids may prevent feed oxidation and
a two way mechanism, that is, may contribute to egg formation. These
its conversion to L-dehydroascorbic acid, benefcial protective effects of vitamins
a particularly inert radical. This reaction were evidenced by increases of egg/bird/
is reversible and the interconversion of day; feed intake and effciency in treatment
these molecules forms a redox system groups in comparison to control chickens.
and the basic physiology if their actions,
because both show vitamin C activity. This study is in agreement with the fndings
The other route, is the formation of of Sahin and Kucuk (22), who reported that
an ascorbate radical that destroys free a combination of 200 mg of vitamin C and
radicals generated by oxygen, which 250 mg of vitamin E provides the greatest
includes the hydroxyl (OH*), mono-oxygen performance in japanese quails reared
(O*) and the superoxides (O *) and also under heat stress. That combination can
2
in the transfer of radical equivalents from be considered as a protective management
lipid phases to aqueous compartment. practice in a poultry diet, ameliorating the
In realizing this function, the vitamin detrimental effects of heat stress. In the
enters into a synergistic action with other same way, Ciftci et al (23), reported that
protective enzymes such as, catalase vitamin E can alleviate the depression in egg
(CAT), superoxide dismutase (SOD) production in heat stressed laying chickens.
and glutathione peroxidase (GSHPx). However, our report is not in agreement
Puthpongsiriporn et al (19), confrmed in with the fndings of Sosnowka-Czajka et al
vitro that the addition of vitamin C, the (24), who found that dietary supplements
rate of proteolytic induction by hydrogen of vitamin C (40 mg/kg) and vitamin E
peroxide (H O) and the destruction of (70 mg/kg) did not increase the tolerance
2 2
SOD. In its scavenging function for free of broilers to high ambient temperatures
radicals generated in the cell membranes, and failed to offset the negative effects of
the vitamin helps in the conversion of the hyperthermia. Probably due to low doses REVISTA MVZ CÓRDOBA • Volumen 16(1), Enero - Abril 20112290
of the vitamins supplemented or specifc Based on these results, it is concluded
factors that affects the biosynthesis or that dietary supplementation of laying
turnover of both vitamins (25). Besides, chickens with vitamins C and E singly or
Sahin et al (26) have demonstrated that in its combined form, can attenuate heat
a combination of 250 mg of vitamin C and stress induced oxidative damage. This is
250 mg of vitamin E provides the greatest evidenced by the increase in the productive
performance in japanese quails reared parameters of the treatment groups when
under heat stress. Furthermore, Ciftci et compared to control.
al (23) reported that the combination of
vitamins C and E can attenuate the heat Acknowledgement
induced oxidative damage at the cell level.
These authors concluded that the positive The authors are grateful to the management
effects were evidenced by increases of of the commercial poultry layer farm “La
growth performances, egg production Casas II” for their technical assistance.
and improvement of egg qualities in
comparison to non-supplemented birds.
A probable indication, that the two
antioxidants potentiate their action
during the inactivation process of reactive
oxygen species.
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