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Effects of a phytogenic feed additive on growth performance, selected blood criteria and jejunal morphology in broiler chickens

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The study was conducted to examine the effects of a phytogenic feed additive (PFA; BIOSTRONG® 510) on growth performance, selected blood parameters and jejunal morphology in broiler chickens. The PFA consists of a mixture of essential oils with thymol and anethole as leading active substances, as well as different herbs and spices. A total of 264 1-d-old Cobb male broilers were randomly allocated to 2 dietary treatments, with 6 replicates per treatment and 22 birds each replicate. The experiment lasted 42 days. The dietary treatments were a starter and grower diet without feed additives (control), or the diets supplemented with 150 mg/kg of the PFA. Body weight and feed intake were not significantly influenced by PFA feeding compared with the control during all experimental periods. During the grower phase (22 - 42 d of age) and during the whole period (1 - 42 d of age) the PFA significantly improved (P<0.05) feed conversion ratio. Serum total protein, albumin, total cholesterol and leucocytes were increased by PFA feeding. Furthermore, villus height to crypt depth ratio in the jejunum was increased by PFA feeding. In conclusion, the results of this study show that inclusion of PFA lead to morphological changes in the jejunum, which might influence nutrient absorption and thus, improved FCR.
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Emir. J. Food Agric. 2013. 25 (7): 549-554
doi: 10.9755/ejfa.v25i7.12364
http://www.ejfa.info/
549
ANIMAL SCIENCE
Effects of a phytogenic feed additive on growth performance, selected blood
criteria and jejunal morphology in broiler chickens
Abdulkarim A. Amad1*, K. R. Wendler2and J. Zentek3
1Department of Animal Production, Faculty of Agriculture and Veterinary, Thamar University,
Dhamar, Yemen
2Delacon Biotechnik, Steyregg, Austria
3Institute of Animal Nutrition, Department of Veterinary Medicine, Freie Universität Berlin, Berlin, Germany
Abstract
The study was conducted to examine the effects of a phytogenic feed additive (PFA; BIOSTRONG® 510) on
growth performance, selected blood parameters and jejunal morphology in broiler chickens. The PFA consists
of a mixture of essential oils with thymol and anethole as leading active substances, as well as different herbs
and spices. A total of 264 1-d-old Cobb male broilers were randomly allocated to 2 dietary treatments, with 6
replicates per treatment and 22 birds each replicate. The experiment lasted 42 days. The dietary treatments were
a starter and grower diet without feed additives (control), or the diets supplemented with 150 mg/kg of the PFA.
Body weight and feed intake were not significantly influenced by PFA feeding compared with the control
during all experimental periods. During the grower phase (22 - 42 d of age) and during the whole period (1 - 42
d of age) the PFA significantly improved (P<0.05) feed conversion ratio. Serum total protein, albumin, total
cholesterol and leucocytes were increased by PFA feeding. Furthermore, villus height to crypt depth ratio in the
jejunum was increased by PFA feeding. In conclusion, the results of this study show that inclusion of PFA lead
to morphological changes in the jejunum, which might influence nutrient absorption and thus, improved FCR.
Key words: Broiler chicken, Performance, Blood parameters, Jejunal morphology
Introduction
The ban of antibiotic growth promoters (AGP)
in poultry feeds intensified the search for
alternatives improving the health and productivity
of broiler chickens (Barreto et al., 2008). Such
alternatives are probiotics, prebiotics and organic
acids, which are added to the feed (Huyghebaert et
al., 2011). Also phytogenic feed additives (PFA)
were shown to enhance performance in AGP-free
livestock production (Alçiçek et al., 2003; Steiner,
2009). Phytogenic feed additives consist of a broad
variety of substances, mainly extracts from plant
materials, such as flowers, buds, seeds, leaves,
twigs, bark, herbs, wood, fruits and roots (Burt,
2004). The active molecules include many different
secondary plant metabolites, resulting in a broad
range of physiological effects, like secretolytic and
spasmolytic, or immune-stimulative effects (Lee et
al., 2004a).
PFA are generally recognized as natural feed
additives and safe to the animal. However, results
of studies concerning the use of PFA in broiler
nutrition are inconsistent (Windisch et al., 2008).
Some authors stated significant improvement of
broiler performance (Ertas et al., 2005; Cross et al.,
2007), whereas others reported no effects on BW
gain and feed intake (Lee et al., 2003; Jamroz et al.,
2005; Nasir and Grashorn, 2010) or feed
conversion ratio (Ocak et al., 2008). These
discrepancies may be due to numerous factors such
as type and parts of plants used, their physical
properties, time of harvest, the preparation method
of PFA and their compatibility with other feed
components (Jang et al., 2007). Furthermore, the
mode of action of these additives is not fully
clarified yet and in vivo studies are limited. Plant
extracts have been shown to influence digestion and
secretion of digestive enzymes (Platel and
Srinivasan, 2000; Williams and Losa, 2001) to
increase absorption of micronutrients (Usha et al.,
2010) and to exhibit antibacterial, antiviral and
Received 14 May 2012; Revised 29 December 2012
; Accepted
08 January 2013; Published Online 01 May 2013
*Corresponding Author
Abdulkarim A. Amad
Department of Animal Production, Faculty of Agriculture and
Veterinary, Thamar University, Dhamar, Yemen
Email: al_absie@yahoo.com
Abdulkarim A. Amad et al.
550
antioxidant activities (Brenes and Roura, 2010).
However, only few studies investigated the effects
of PFA on intestinal morphology in broiler
chickens. Therefore, the aim of the present study
was to examine the effect of a commercial PFA on
performance, intestinal morphology and selected
blood parameters in broiler chickens.
Materials and Methods
Two hundred sixty four 1-d-old male Cobb
chickens were weighed and randomly allotted to 2
experimental treatments. Each treatment consisted
of 6 replicates with 22 birds per replicate. The
dietary treatments were a starter and grower basal
diet without any feed additives used as a control or
the basal diets supplemented with 150 mg/kg of a
commercial PFA (BIOSTRONG®510, Delacon,
Steyregg, Austria) used as experimental diets. The
PFA consisted of a mixture of essential oils, with
thymol and anethole as leading active substances,
as well as different herbs and spices. The
compositions of the basal diets are shown in Table
1. Control and experimental diets were formulated
to be iso-nutritive and to meet the requirements for
broiler chickens during starter and grower phase.
Feed and water were available ad libitum. Feed
consumption and BW of the birds were recorded
weekly and were used to calculate broiler
performance (weight gain, feed intake, feed
conversion ratio).
Blood samples were taken at 35 d of age from
the brachial vein from 12 birds per treatment group
(2 birds per pen). Blood samples were separated by
centrifuge, and serum was analyzed for glucose,
total cholesterol, triglycerides, albumin and total
protein using commercial test kits. Blood cell
counts were determined by commercial cell
counter.
At 42 d of age, 9 birds per treatment were
slaughtered and the jejunum was removed for
assessment of tissue morphology. The tissue
samples were taken from the middle part of the
jejunum (from the entrance of bile duct to Meckel’s
diverticulum, pieces about 5 cm in length),
carefully cleansed and then fixed in 4% buffered
formalin for 2 days. The further processing
consisted of serial dehydration in PBS and graded
ethanol solutions, clearing with xylene and
embedding in paraffin. Sections of 5 µm were
prepared and placed on glass slides. Tissue samples
were deparaffinised, rehydrated and stained with
haematoxylin and eosin. Villus heights and crypt
depths were examined with a photomicroscope
(Photomikroskop III, Carl Zeiss, Oberkochern,
Germany) fitted with a digital camera (MikroCam 3
MP, Bresser, Rhede, Germany) and images were
analysed using image analysis software (Image
software Bresser MikroCamLab Mikroskopie). A
total of 16 intact well-oriented villus-crypt units
were randomly selected at each tissue sample.
Villus height was measured from the tip of the
villus to the villus-crypt junction, and crypt depth
was defined as the depth of the invagination
between two villi.
Experimental data were analyzed by ANOVA
using SPSS v. 17.0 (Statistical Packages for the
Social Sciences, released August 23, 2008). Data
was tested for homogeneity of variances, and
comparison of means was performed by Tukey test.
The significance level was set at p <0.05.
Results
During the whole experiment, birds were
healthy and the mortality was below 1%.
Performance data for broiler chickens during the
starter and grower phase and for the total
experimental period are summarized in Table 2.
Table 1. Ingredients and nutrient composition of
experimental diets.
Ingredients (%) Starter
1 - 21d
Finisher
22 - 42 d
Soybean meal
(
48%
CP
)
34.50
31.80
Maize 28.46 29.47
Wheat 24.69 24.29
Soy oil 6.80 9.35
1.80
1.51
Monocalcium-phosphate 1.40 1.35
Premix* 1.20 1.20
Chromium oxide 0.50 0.50
DL
-
Methionine
0.30
0.29
L-Lysine 0.25 0.14
Additives** 0.10 0.15
100% 100%
Chemical composition (calculated)
AMEn, (MJ/k
g)
12.59
13.29
Crude protein( %) 22.89 21.50
Crude fibre (%) 2.39 2.32
Lysine (%)
1.43
1.26
Methionine (%)
0.64
0.61
Methionine + Cystein (%) 1.02 0.98
Calcium (%) 1.03 0.90
Total Phosphorus (%)
0.70
0.68
*Supplied per kg of diet: 4000 IU vitamin A (retinyl acetate); 400 IU cholecalciferol; 80
mg (α-tocopherole acetate); 3 mg vitamin K3 (menadione); 2.5 mg thiamin ; 2.5 mg
riboflavin; 25 mg nicotinic acid; 4 mg pyridoxine; 0.02 mg cobalamin; 0.3 mg biotin; 10
mg calcium pantothenate acid; 1 mg folic acid; 800 mg choline chloride; 50 mg Zn (Zinc
oxide); 20 mg Fe (Iron carbonate); 60 mg Mn (manganese oxide); 12 mg Cu (copper
sulfate-pentahydrate); 0.45 mg J (calcium iodate; 0.30 mg Co (cobalt- (II)-sulfate-
heptahydrate); 0.35 mg Se (sodium selenite); 1.3 g Na (sodium chloride); 0.55 g Mg
(magnesium oxide) ; ** Additives: Control = without active substances (PFA); Treatment
= Biostrong® 150 mg/kg feed.
Emir. J. Food Agric. 2013. 25 (7): 549-554
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551
For all experimental periods, there was no
effect (P>0.05) of the PFA on BWG and feed
intake. Feed conversion ratio was significantly
improved (P<0.05) in the grower phase (22 - 42 d
of age) as well as during the whole experimental
period (1- 42 d of age) due to PFA
supplementation.
Villus heights, crypt depths and villus height:
crypt depth ratios of jejunal tissue samples are
presented in Table 4. In broilers fed diets
supplemented with PFA, there were no differences
between the villus height and crypt depth could be
observed compared to the control (Figure 1). Villus
height: crypt depth ratio was significantly (P<0.05)
increased in birds fed PFA compared to the control.
Effect of the phytogenic feed additive on some
blood parameters in broilers were summarized in
Table 3. Serum total protein, albumin, cholesterol
and leucocytes were increased (P<0.05), while
serum glucose, triglycerides, hemoglobin and
erythrocytes were not affected by PFA feeding.
Table 2. Effect of the phytogenic feed additive on broiler performance during the starter and grower period (means ± SD).
ab Values with different superscript within lines differ significantly (P<0.05)
Table 3. Effect of the phytogenic feed additive on some blood parameters in broilers (35th d of age; means ± SD).
Parameters Treatments P-value
Control PFA (150 mg/kg)
Serum total protein (g/l) 27.03
a
±3.65 30.64
b
±1.38 <0.004
Serum albumin (g/l)
11.67
a
±2.15
14.22
b
±0.87
0.001
Serum glu
cose (mmol/l)
14.22
±1.49
14.99
±0.60
0.11
Serum Cholesterol (mmol/l) 3.00
a
±0.65 3.84
b
±0.22 <0.001
Triglycerides (mmol/l) 1.33 ±1.23 1.86 ±0.71 0.21
Erythrocytes
(Tpt/l)
2.27
±0.10
2.34
±0.27
0.31
Leucocytes
(Tpt/l)
175.8
a
±2.4
183.5
b
±9.5
0.012
Haemoglobin (mmol/l) 4.94 ±0.25 5.22 ±0.48 0.09
ab Values with different superscript within lines differ significantly (P<0.05)
Table 4. Effect of the phytogenic feed additive on histomorphological parameters of the jejunum in broilers (means ± SD).
Parameters
Treatments
P- value
Control
PFA
(
150
mg
/
kg
)
Villus height (µm)
1447±125.4
1569±120.9
0.068
Crypt depth (µm)
199±21.0
179±18.6
0.061
Villus height:crypt depth 7.3
a
±0.8 8.8
b
±0.9 0.004
ab Values with different superscript within lines differ significantly (P<0.05)
Period
Treatments
P-value
C
ontrol
PFA
(
150
mg
/
kg
)
Average body weight
gain (g)
1
-
21
d
797
±67
813
±28
0.62
22 - 42 d 2108 ±102 2144
±150 0.64
1 - 42 d 2906 ±134 2956 ±173 0.58
Average feed intake (g)
1 - 21 d 1124 ±108 1106 ±99 0.76
22
-
42
d
3332
±130
3259
±211
0.49
1
-
42
d
4456
±202
4365
±287
0.54
Feed
conver
sion ratio (g/g)
1
-
21
d
1.41
±0.07
1.36
±0.08
0.295
22 - 42 d 1.58
a
±0.04 1.52
b
±0.03 0.013
1 - 42 d 1.53
a
±0.04 1.48
b
±0.02 0.011
Abdulkarim A. Amad et al.
552
Figure 1. Villus height and crypt depth in the jejunum of broilers fed diets with or without the phytogenic feed additive at
42 days of age, left control, right phytogenic feed additive.
Discussion
In the present study, there was no effect of the
tested PFA on BW and feed intake in broilers.
These results are consistent with the studies of Jang
et al. (2007) and Erdogan et al. (2010), who did not
find effects of different phytogenic compounds on
broiler growth performance. However, FCR was
significantly improved in the present study.
Consistently, Jamroz et al. (2005) reported
improved FCR due to the addition of a plant
extract, containing cinnamaldehyde, carvacrol and
capsaicin, to a maize or wheat and barley based diet
by 4.1 or 2.0%, respectively, whereas BW was not
affected by treatment. Al-Kassie (2009) showed
that the addition of 200 ppm oil extract derived
from thyme and cinnamon to broiler diets
significantly improved BW gain and FCR during a
growing period of 6 weeks and Ocak et al. (2008)
reported higher (P< 0.05) BW at 21 and 42 d of age
as well as higher (P< 0.05) BW gain from 7 to 35
days of age in broilers fed peppermint and thyme
compared to the controls. The above mentioned
studies, reporting improved FCR, have in common,
that the added substances mainly consist of
essential oils. Essential oils exert antimicrobial
activity in the digestive tract of animals (Lee et al.,
2004; Al-Kassie, 2010). It is hypothesized that gut
microflora reduces nutrients available to the animal
by enforcing the intestinal cell turnover and thereby
increasing the intestinal requirement for nutrients to
maintain tissue integrity. Moreover, intestinal
microflora and epithelial cells have to compete for
nutrients (Dibner and Richards, 2005; Lan et al.,
2005). By a reduction of intestinal microflora,
essential oils may lead to moderate cell turnover, to
decreased intestinal nutrient requirements and to
less competition for available nutrients. As a
consequence, FCR is improved because more
nutrients are used for BW gain instead of tissue
maintenance or microbial growth.
The increased nutrient supply for growth is
reflected in enhanced nutrient transport in the
blood. For example, Ghazalah and Ali (2008)
observed higher levels of total protein, albumin and
globulin in the blood serum of birds when fed 0.5%
rosemary leaves. Similar results were obtained in
the present study, where higher contents of total
protein and albumin in the blood serum of PFA fed
animals may also indicate enhanced nutrient supply
and transport. Furthermore, Tekeli et al. (2006)
reported increased blood glucose concentration by
Zingiber officinale supplementation and increased
triglyceride concentration by both Zingiber
officinale and Syzygium Aromaticum
supplementation. In the present study, there was no
effect of PFA on blood glucose and triglyceride
concentrations. Calislar et al. (2009) found effects
neither on triglycerides nor on blood cholesterol
levels by application of a PFA containing
Origanum vulgare ssp. hirtum extract. In general,
essential oils are more often associated with
hypocholesterolemic properties (Lee et al., 2004).
In contrast, in the present study chicken fed the
PFA showed higher serum cholesterol
concentrations compared to the control animals.
This discrepancy may be due to the combination of
essential oils and pungent substances which were
also included in the used PFA. Pungent substances
increase digestive secretions including enzymes and
bile. The higher serum cholesterol content, which
was observed in the PFA fed animals of the present
study, may be the result of an increased lipid
digestibility due to a higher secretion of bile and
digestive enzymes. The improvement of FCR as
Emir. J. Food Agric. 2013. 25 (7): 549-554
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553
well as the increase of blood nutrient concentrations
supports this assumption, although it remains
speculative as nutrient digestibilities have not been
investigated in the present study.
Regarding the intestinal morphology, heavier
chickens are generally associated with longer villi,
greater villus width and higher villus surface area
as compared to lighter ones (Adibmoradi et al.,
2006; Incharoen et al., 2010). In the present study
there were insignificantly increased villus heights
and decreased crypt depths in the jejunum of birds
receiving 150 mg/kg PFA compared to the control.
Accordingly, the villus height: crypt depth ratio
was significantly higher in the birds fed the PFA
compared to the control. These findings were
consistent to Adibmoradi et al. (2006) who reported
that jejunal villus height was increased whereas
crypt depths were decreased, leading to increased
villus height: crypt depth ratio in birds fed graded
levels of garlic meal. It has been suggested that
longer villi would result in an increased surface
area and higher absorption of available nutrients
(Caspary, 1992; Yasar and Forbes, 1999). A higher
absorptive capacity of the intestine of PFA fed
animals is also supported by higher blood nutrient
concentrations of those animals, as observed in the
present study. However, although Jamroz et al.
(2006) reported similar improvement of FCR due to
the supplementation with a plant extract containing
carvacrol, cinnamaldehyde and capsicum oleoresin,
the authors could not find an effect of the plant
extract on intestinal morphology in broilers at 42 d
of age. Thus, for PFA containing essential oils as
well as pungent substances further, eventually
synergistic, effects or other modes of action cannot
be ruled out.
Conclusion
In the present study, the addition of the
phytogenic feed additive BIOSTRONG® 510 to
broiler diets significantly improved feed conversion
ratio. The observed improvement of feed
conversion ratio may be caused by a combination
of different effects, including enhancement of
digestive secretions, antimicrobial effects of
essential oils as well as enlargement of intestinal
absorptive surface. However, further studies are
necessary to evaluate the effects of various
substances present in phytogenic feed additives and
to clarify their specific modes of action.
References
Alçiçek, A., M. Bozkurt and M. Ç abuk. 2003. The
effect of an essential oil combination derived
from selected herbs growing wild in Turkey
on broiler performance. S. Afr. J. Ani. Sci.
33:89-94.
Al-Kassie, G. A. M. 2009. Influence of two plant
extracts derived from thyme and cinnamon on
broiler performance. Pak. Vet. J. 29: 69-173.
Al-Kassie, G. A. M. 2010. The Effect of Thyme
and Cinnamon on the Microbial Balance in
Gastro Intestinal Tract on Broiler Chicks. Int.
J. Poult. Sci. 9:495-498.
Adibmoradi, M., B. Navidshad, J. Seifdavati and
M. Royan. 2006. Effect of dietary garlic meal
on histological structure of small intestinal in
broiler chickens. J. Poult. Sci. 43:378–383.
Barreto, M. S. R., J. F. M. Menten, A. M. C.
Racanicci, P. W. Z. Pereira and P. V. Rizzo.
2008. Plant Extracts used as Growth
Promoters in Broilers. Bra. J. Poult. Sci.
10:109-115.
Brenes, A. and E. Roura. 2010. Essential oils in
poultry nutrition: Main effects and modes of
action. Anim. Feed Sci. Techn. 158: 1–14.
Burt, S. 2004. Essential oils: their antibacterial
properties and potential applications in foods -
a review. Int. J. Food Microb. 94:223-253.
Calislar, S., I. Gemci and A. Karnalak. 2009.
Effects of Oregano-Stim® on broiler chick
performance and some blood parameters. J.
Anim. Vet. Adv. 8:2617-2620.
Caspary, W. F. 1992. Physiology and
pathphysiology of intestinal absorption. Am. J.
Clin. Nutr. 55:299S-308S.
Cross, D. E., R. M. Mcdevitt, K. Hillman and T.
Acamovic. 2007. The effect of herbs and their
associated essential oils on performance,
dietary digestibility and gut microflora in
chickens from 7 to 28 days of age. Br. Poult.
Sci. 48:496–506.
Dibner, J. J. and J.D. Richards. 2005. Antibiotic
growth promoters in agriculture: History and
mode of action. Poult. Sci. 84:634-643.
Erdogan, Z. S., S. Erdogan, O. Aslantas and S. C.
Elik. 2010. Effects of dietary supplementation
of synbiotics and phytobiotics on
performance, caecal coliform population and
some oxidant/antioxidant parameters of
broilers. J. Anim. Phys. Anim. Nutr. 94:40-48.
Ertas, O. N., T Güler, M. Ç iftçi, B. Dalkiliçand Ü .
G. Simsek. 2005. The effect of an essential oil
Abdulkarim A. Amad et al.
554
mix derived from oregano, clove and anise on
broiler performance. Int. J. Poult. Sci. 4:879-
884.
Incharoen, T., K. Yamauchi, N. Thongwittaya.
2010. Intestinal villus histological alterations
in broilers fed dietary dried fermented ginger.
J. Anim. Phys Anim. Nutr. 94:130-137.
Ghazalah, A. A. and A. M. Ali. 2008. Rosemary
Leaves as a Dietary Supplement for Growth in
Broiler Chickens. Int. J. Poult. Sci. 7:234-239.
Huyghebaert, G., R. Ducatelle and F. V. Immerseel.
2011. An update on alternatives to
antimicrobial growth promoters for broilers.
The Veterinary Journal 187:182–188.
Jamroz, D., T. Wertelecki, M. Houszka and C.
Kamel. 2006. Influence of diet type on the
inclusion of plant origin active substances on
morphological and histochemical
characteristics of the stomach and jejunum
walls in chicken. J. Anim. Phys. Anim. Nutr.
90:255–268.
Jamroz, D., A. Wiliczkiewicz, T. Wertelecki, J.
Orda and J. Skorupinska. 2005. Use of active
substances of plant origin in chicken diets
based on maize and locally cereals. Br. Poult.
Sci. 46:485-493.
Jang, I. S., Y. H. Ko, S. Y. Kang and C. Y. Lee.
2007. Effect of commercial essential oils on
growth performance, digestive enzyme
activity and intestinal microflora population in
broiler chickens. Anim. Feed. Sci. Techn.
134:304–315.
Lan, Y., M. W. Verstegen, S. Tamminga and B. A.
Williams. 2005. The role of the commensal
gut microbial community in broiler chickens.
World Poult. Sci. J. 61:95-104.
Lee, K. W., H. Everts., H. J. Kappert and A. C.
Beynen. 2004. Growth performance of broiler
chickens fed a carboxymethyl cellulose
containing diet with supplemental carvacrol
and/or cinnamaldehyde. Int. J. Poult. Sci.
3:619–622.
Lee, K. W., H. Everts and A. C. Beynen. 2004a.
Essential oil in broiler nutrition. Poult. Sci.
3:738–752.
Lee, K. W., H. Everts, H. J. Kappert, M. Frehner,
R. Losa and A. C. Beynen. 2003. Effects of
dietary essential oil components on growth
performance, digestive enzymes and lipid
metabolism in female broiler chickens. Br.
Poult. Sci. 44:450-457.
Nasir, Z. and M. A. Grashorn. 2010. Effects of
Echinacea purpurea and Nigella sativa
supplementation on Broiler performance,
carcass and meat quality. J. Anim. Feed Sci.
19:94–104.
Ocak, N., G. Erener, F. Burakak, M. Sungu, A.
Altop and A. Ozmen. 2008. Performance of
broilers fed diets supplemented with dry
peppermint (Mentha piperita L.) or thyme
(Thymus vulgaris L.) leaves as growth
promoter source. Cz. J. Anim. Sci. 53:169–
175.
Platel, K. and K. Srinivasan. 2000. Influence of
dietary spices and their active principles on
pancreatic digestive enzymes in albino rats.
Nahrung (food) 44:42–46.
Steiner, T. 2009. Phytogenics in Animal Nutrition.
Natural Concepts to Optimize Gut health and
Performance. Nottingham University Press.
Nottingham, United Kingdom.
Tekeli, A., L. Celik, H. R. Kutlu and M. Gorgulu.
2006. Effect of dietary supplemental plant
extracts on performance, carcass
characteristics, digestive system development,
intestinal microflora and some blood
parameters of broiler chicks. XII, EPC, 10-14
September, Verona, Italy.
Usha, N., S. Prakash and K. Srinivasan. 2010.
Beneficial influence of dietary spices on the
ultrastructure and fluidity of the intestinal
brush border in rats. Br. J. Nutr. 104:31-39.
Williams, P. and R. Losa, 2001. The use of
essential oils and their compounds in poultry
nutrition. World Poult. 17:14–15.
Windisch, W. M., K. Schedle, C. Plitzner and A.
Kroismayr. 2008. Use of phytogenic products
as feed additives for swine and poultry. J.
Anim. Sci. 86:140-148.
Yasar, S. and J. M. Forbes. 1999. Performance and
gastrointestinal response of broiler chicks fed
on cereal grain-based foods soaked in water.
Br. Poult. Sci. 40:65–76.
... OEO can be used as a nutritional feed additive for ruminants to improve the performance and feed efficiency of dairy cows and meat animals. OEO can improve the performance of chickens (Botsoglou et al. 2002;Amad et al. 2013;Peng et al. 2016;Ramirez et al. 2021;Zhang et al. 2021;Roofchaee et al., 2011), pigs (Forte et al. 2017;Liang et al. 2017;Cheng et al. 2018;Deng et al. 2018;Jugl-Chizzola et al., 2006), and rabbits (Botsoglou et al. 2004) to achieve the effect of fattening animals. On the Qinghai-Tibet Plateau, the oxygen content is low. ...
... and the ADG in group C was the highest. The ADG in group C was significant, indicating that OEO can improve the daily gain in Sewa sheep; these results are similar to those obtained in sheep (Chu 2019), chickens (Botsoglou et al. 2002;Amad et al. 2013;Peng et al. 2016;[AQ2]; Ramirez et al. 2021;Zhang et al. 2021), pigs (Forte et al. 2017;Liang et al. 2017;Cheng et al. 2018;Deng et al. 2018) and rabbits (Botsoglou et al. 2004). The total weight gain of groups B, C and D was significantly higher than that of group A (p< .05), ...
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The purpose of this experiment was to study the effects of oregano essential oil (OEO) on the performance, intestinal morphology and intestinal flora of fattening Sewa sheep. Sixty 20-month-old Sewa sheep with similar body weights (BWs) and in good health were randomly divided into four groups. The groups were fed a diet containing 0 mg/kg OEO (group A), 150 mg/kg (group B), 300 mg/kg (group C) or 450 mg/kg (group D). Daily gain, slaughter rate and other production performance parameters were analysed in the test sheep (mean ± standard error). Intestinal morphology was analysed by tissue sectioning, and intestinal flora was analysed by 16S rRNA genome sequencing. The indexes, including average daily gain (ADG), slaughter rate, villus length of the small intestine and number of beneficial bacteria in the intestinal flora, in group C were significantly higher than those in the other groups. Supplementation with 300 mg/kg OEO concentrate in the diets can improve the growth performance of Sewa sheep by changing their intestinal morphology and modifying their intestinal flora structure. Conclusively, these encourage to further verifying in practice positive evidence in improving growth performance of OEO supplementation in the diets for Sewa sheep. • Highlights • Oregano essential oil (OEO) can improve the performance of Sewa sheep by changing the intestinal morphology and regulating the intestinal flora structure.
... In a study, it was shown that the use of a mixture of essential oils of several plant species (anise, citrus peel, and oregano) prevented the reduction of villi height. Although in the condition of animal health, the use of a mixture of herbs and medicinal plants could increase the growth of intestinal villi compared to the control, which was consistent with the results of this study [38,39] . Therefore, plant extracts and essences can increase food consumption through the mentioned cases. ...
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The industrial maintenance of livestock and poultry on a large scale in an intensive manner has increased the possibility of diseases, which reduces the occurrence of these diseases helps to boost growth and improves production traits. Today, the use of growth-promoting antibiotics has been limited due to the possibility of bacterial resistance and also transmission through manufactured products to consumers. Medicinal plants with antimicrobial effects and reduced serum lipids have been proposed as suitable alternatives for antibiotics. The origin of many medicines are herbal plants because due to the lipophilic nature of the effective oils found in some medicinal plants, these compounds can completely disrupt the membrane structure of bacteria, especially Gram-negative bacteria, and even some effective oils in essential oils have Irritation of the digestive system, increasing the production of digestive enzymes, improving the use of digestive products and the body's immune response. The most important biological activity of medicinal plants is related to antioxidant and antibacterial activities, related to their biologically active molecules such as carvacrol, thy-mol, cineol, allicin, capsaicin, piperine, etc. The property of stopping the reproduction of the disease agent or the lethality of the disease agent is a common point between chemical drugs and medicinal plants, but creating a protective layer on the intestine to prevent the penetration and growth of the coccidiosis agent in the intestines and stimulating the body's immune system against the disease agent is a unique feature. The desire of the world community to consume animal products free of chemical compound residues and to prevent the development of bacterial resistance has led to more use of plant resources.
... The finding of this work is agreed by the report of Lavinia et al. (2009) who provided the data regarding the changes in the microscopic structure of chicken duodenum and immune response as a consequence of aromatic plant extracted essential oils present in their feed. The findings of the present study were consistent to Adibmoradi et al.(2006) and Abdulkarim et al.(2013) who reported that jejunal villus height was increased leading to increased villus height: crypt depth ratio in birds fed with phytogenic feed additive and garlic meal. Similarly, in the present study, active constituents deposited in the yolk might have stimulated development of digestive system with higher villi height contributing to increased surface area for more nutritional absorption and lower crypt depth caused the favorable microbial environment of intestine in the progeny of herb supplemented breeders. ...
... The finding of this work is agreed by the report of Lavinia et al. (2009) who provided the data regarding the changes in the microscopic structure of chicken duodenum and immune response as a consequence of aromatic plant extracted essential oils present in their feed. The findings of the present study were consistent to Adibmoradi et al.(2006) and Abdulkarim et al.(2013) who reported that jejunal villus height was increased leading to increased villus height: crypt depth ratio in birds fed with phytogenic feed additive and garlic meal. Similarly, in the present study, active constituents deposited in the yolk might have stimulated development of digestive system with higher villi height contributing to increased surface area for more nutritional absorption and lower crypt depth caused the favorable microbial environment of intestine in the progeny of herb supplemented breeders. ...
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... These findings are consistent with the results of other studies, which reported that adding herbal plant extracts could increase the villus length (26,32) and VH/CD ratio (37,38). In addition, Amad et al. (39) showed that supplementation of herbal plant additive to poultry diet could change jejunal tissue, which is useful for better absorbing nutrients and improving functions such as FCR. Meanwhile, according to Viveros et al. (40), phenolic derivatives can alter the intestinal microbial ecology in poultry and cause positive changes in broiler intestinal bacteria. ...
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Background: Herbal antioxidants have beneficial effects on health and performance. Meanwhile, medicinal plants and their derivations are utilized as growth and immunity promoter. Objectives: This research aimed to evaluate the effects of garlic powder and Satureja Khuzestanica essential oil (SKEO) on broiler performance, blood lipid profile, immune responses, intestinal microflora, and morphology. Methods: In total, 400 male chickens were randomly divided into five groups. Treatments included garlic powder (2 and 4%) and SKEO (400 and 500 mg/kg). Those in the control group received no intervention. On the 35th day of the experiment, the immune system of subjects was investigated, and at the end of the study, performance and blood lipid profile were analyzed. Also, the jejunal and ileal contents were separated to investigate the intestinal morphology and microflora. Results: Administration of herbal extracts was associated with improved performance, such as feed intake, BWG, and FCR (P < 0.05). Treatments could diminish the serum concentrations of lipid profile, including cholesterol, triglycerides, and LDL (P < 0.05). Meanwhile, the number of harmful intestinal bacteria was reduced by garlic (4% of diet) and SKEO (500 mg/kg) treatments (P < 0.05). Also, morphological characteristics of the intestine were improved (P < 0.05). Herbal plant supplement remarkably increased the villus length, villus length to crypt depth, and villus area (P < 0.05), but did not affect the immune responses (P > 0.05). Conclusions: This study demonstrated that dietary inclusion of herbal extracts is potentially an effective strategy for improving health and performance in broiler chickens.
... The similar weights of the organ of broiler chickens fed the control and diets supplemented with neem leaf meal suggest that the physiological functions and anatomical features of these organs were not compromised by dietary supplementation of neem leaf meal and thus neem leaf as a phytogenic feed supplement has no physiological and pathological effect on the organs indicating that the levels of phytochemical in neem leaf did not trigger the activities of the organs to negatively affect the health status of the birds. This result corroborates the reports that phytogenic feed additives did not hamper the organ weights of broiler chickens [35]. The fact that the organs of the birds were not compromised implied that neem leaf as a phytogenic feed additive is safe in broiler chicken diet. ...
... efficiency of animals (Amad et al., 2013;Hernandez et al., 2004). ...
Article
This experiment was conducted to investigate the effect of star anise essential oil (SAO) supplementation in diets with different energy levels on growth performance, nutrient metabolic efficiency of broilers. One hundred and ninety‐two Arbor Acres male broiler chicks at 28 days of age were divided into a 3 × 4 factorial arrangement design with three dietary energy levels (13.41, 12.82, 12.23 MJ/kg) and 4 levels of SAO supplementation (0, 200, 400, and 600 mg/kg of diet). Dietary supplementation with SAO increased (p < .05) apparent metabolic efficiency of CP, EE, GE, and all of the amino acids except Trp. Significant interactions were noted between energy level and SAO administration for metabolic efficiency of CP, all of the amino acids except Cys. Inclusion of SAO enhanced apparent nutrient metabolic efficiency of broilers in a dose‐dependent manner, birds supplemented with 400 mg/kg of SAO in high‐energy diets appeared to contain highest nutrient metabolic efficiency, moreover, the metabolic efficiency of nutrients in low‐energy diets along with 200 or 400 mg/kg of SAO was similar with that in high‐energy diets without SAO, which indicated that the SAO might ameliorate the negative effects of reduced dietary metabolic energy on nutrient utilization in broilers.
... They concluded that the liver weight decreased in response to adding 0.5 % tarragon's powder in diet of broilers. In another study, Amad et al. (2013) reported that using phytogenic feed additive with combination of anethole and thymol in broiler chicks diets enhances the digestive and bile enzyme secretions resulting in higher lipid digestibility. In another study (Visavadiya and Narasimhacharya, 2011), it was shown that feeding diets containing Glycyrrhiza glabra and Withania somnifera to rats with high cholesterol level can increase HMG-COA reductase activity and secretion of bile acids but decrease liver weight. ...
Article
DLK1 (protein delta homolog 1) plays an important role in production of adipocytes, muscle development, wound healing, pancreas, liver and lung cells development and also in the development of meat quality, digestion and growth performance. Therefore, the goal of this research was to investigate the effects of different levels of fennel seed power in the diet on growth performance and on DLK1 gene expression in brain, adipose, femur (leg) muscle and rumen muscle tissues of Kermani lambs. Dietary treatments including different levels of fennel seed powder (0, 1 and 2 % of diet DM) were fed to 3 groups of lambs (each group contained 10 animals) for three months. Some physiological parameters relating to muscle and adipose development were measured. Tissues including brain, adipose tissue, femur (leg) muscle and rumen muscle were collected for expression analysis of the DLK1 gene. In this study, increasing the level of fennel seed powder in diets of lambs, increased the amount of DLK1 gene expression in the femur muscle and rumen tissues. Feeding 2 % fennel in comparison to the control diet (0 %) resulted in a significant difference in the amount of DLK1 gene expression in the femur (leg) muscle and in the rumen muscle (P < 0.05). Maximum gene expression rate was observed in all studied tissues of lambs fed diets with 2 % fennel in comparison to 0%. On the other hand, final weight, live daily gain, dry matter intake, warm carcass weight, weight of back muscle (loin), weight of femur (leg) muscle, weight of lean meat and eye muscle area were higher for animals fed with 2 % fennel than those fed control diet, but weight of liver was lower in animals fed with 2 % fennel than those fed control diet. In regards to the results of this investigation, it can be concluded that fennel can be used for increasing DLK1 gene expression in some tissues, like muscle, and consequently for increasing animal growth and muscle mass, which is important in the sheep industry.
Article
This study was performed to determine the early-life (first month of age) supplementation of liquid feed with fennel seed powder (FSP) or oregano leaf powder (OLP) on growth performance, health, and blood biochemical attributes in preweaning dairy calves. Holstein female calves (n = 57; 1 d of age; 34.1 ± 0.97 kg of BW; mean ± SE) were assigned randomly to receive liquid feed (colostrum and milk) with no added herbal plants (CON) or supplemented with FSP (3 g/d) or OLP (30 g/d) during the first month of age. The calves received pooled colostrum (4.5 kg/d on the first 2 d of life; total solids = 25.0% ± 1.24; mean ± SD) and then pooled waste milk (6 kg/d from d 3 to 44, 5 kg/d from d 45 to 46, 4 kg/d from d 47 to 48, and 3 kg/d from d 49 to 50 of the trial; total solids = 12.54% ± 0.50) to ensure they receive same mixed liquid feed daily. The calves had unlimited access to the starter feed and fresh water and remained in the study until weaning on d 51 of age. The average mean temperature-humidity index was 70.1 units (ranging between 61.9 to 78.2) during the experiment, indicating a borderline degree of environmental heat-load. The amount of starter feed offered and refused was recorded daily. The calves were weighed immediately after birth and every 10 d thereafter, before the morning feeding. Jugular blood samples were taken immediately before and 24 h after colostrum feeding, at first month of age, and at weaning to quantify serum concentrations of glucose, urea N, cholesterol, triglycerides, total proteins, albumin, globulin, aspartate transferase, alanine transferase, total antioxidant status, and malondialdehyde. Health checks including rectal temperature, general appearance (on a 1–5 score system), fecal score (on a 1–5 score system), and bovine respiratory disease (BRD; scored using the University of Wisconsin Calf Health Chart) were performed daily, by a veterinarian who was unaware of the calf treatment allocations, for all calves over the study period. A repeated-measures ANOVA was used to compare growth performance and blood metabolites among treatment groups, and a logistic regression model using a binomial distribution (PROC GLIMMIX, SAS v. 9.4, SAS Institute Inc.) was used to assess the chance of elevated rectal temperature (≥39.4°C), general appearance (≥2), diarrhea (≥3), and BRD. A Poisson regression model (PROC GENMOD) was also used to test group differences in the experience of days with elevated rectal temperature and general appearance, and frequency and duration of diarrhea or BRD. Total nutrient intake (DM, CP, and ME, but not ether extract) originating from milk and starter feed was greater in OLP- (but not FSP-) supplemented calves compared with CON group, being partially associated with difference in milk refusal. Calves receiving FSP and OLP had greater average daily gain, BW gain, skeletal gain (withers height or heart girth, respectively), and feed efficiency compared with CON animals with no difference between FSP and OLP. Rectal temperature was lower in FSP- (but not OLP-) supplemented calves compared with CON animals. The CON animals had a greater chance of experiencing higher rectal temperature (≥39.4°C; odds ratio = 1.55 and confidence interval = 1.12–2.15 and odds ratio = 1.33 and confidence interval = 0.92–1.90, respectively, compared with FSP and OLP) and general appearance (≥2; odds ratio = 1.99 and confidence interval = 1.45–2.74 and odds ratio = 1.45 and confidence interval = 1.03–2.05), and diarrhea (odds ratio = 1.47 and confidence interval = 1.11–1.97 and odds ratio = 1.49 and confidence interval = 1.07–2.08) compared with those receiving FSP or OLP; with the chance of BRD being lower in FSP- (but not OLP-) supplemented versus CON animals (odds ratio = 1.59 and confidence interval = 1.13–2.23). As compared with OLP and CON groups, FSP treatment resulted in shorter days with elevated rectal temperature and general appearance. Supplementing FSP or OLP decreased the duration of diarrhea and BRD but not their frequency compared with CON. Duration of diarrhea was not different between FSP- or OLP-supplemented calves but calves supplemented with FSP had shorter days with BRD compared with OLP-supplemented calves. Of the blood constituents measured on d 30, concentration of aspartate transferase was higher in FSP- (but not CON) versus OLP-supplemented calves, indicating a transient liver tissue damage or dysfunction which was subsequently ameliorated. At weaning, blood concentration of triglycerides was higher in FSP and OLP groups compared with CON group. Supplementation of the liquid feed with FSP or OLP, especially FSP, had beneficial effects on calf growth performance and health. Further experiments are warranted for optimizing the dosage and duration of feeding FSP or OLP as feed additives for dairy calves.
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Objective: The purpose of this meta-analysis was to evaluate the effect of dietary essential oils (EOs) on productive performance, nutrient digestibility, and serum metabolite profiles of broiler chickens and to compare their effectiveness as growth-promoting additives against antibiotics. Methods: Peer-reviewed articles were retrieved from Web of Science, Science Direct, PubMed, and Google scholar and selected based on pre-determined criteria. A total of 41 articles containing 55 experiments with 163 treatment units were eligible for analyses. Data were subjected to a meta-analysis based on mixed model methodology considering the doses of EOs as fixed effects and the different studies as random effects. Results: Results showed a linear increase (p<0.001) on body weight gain (BWG) where Antibiotics (FCR) and average daily feed intake decreased (p<0.001) linearly with an increasing dose of EOs. Positive effects were observed on the increased (p<0.01) digestibility of dry matter, crude protein, ether extract, and cecal Lactobacillus while Escherichia coli (E. coli) population in the cecum decreased (p<0.001) linearly. There was a quadratic effect on the weight of gizzard (p<0.01), spleen (p<0.05), bursa of fabricius (p<0.001), and liver (p< 0.10) while carcass, abdominal fat, and pancreas increased (p<0.01) linearly. The dose of EOs linearly increased high density lipoprotein, glucose, protein, and globulin concentrations (p<0.01). In comparison to control and antibiotics, all type of EOs significantly reduced (p<0.001) FCR and tended to increase (p<0.1) BWG and final body weight. Cinnamaldehyde-compound was the only EOs type showing a tendency to increase (p<0.1) carcass weight, albumin, and protein of serum metabolites while this EOs together with EOs-Blend 1 decreased (p<0.01) E. coli population. Low density lipoprotein concentration decreased (p<0.05) with antibiotics and carvacrol-based compound when compared to the control group. Conclusion: This evidence confirms that EOs are suitable to be used as growth promoters and their economical benefit appears to be promising.
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The aim of this experiment was to determine the effect of Orego-Stim® on broiler chick performance and some blood parameters. This research was carried out on the base floor using 120 male Ross PM3 7 days old hybrid chicks. In the 1st week of the research, the chicks were fed with starter diet, then 120 chicks were divided into four groups. Each group has consisted of three replications and each replication contained 10 chicks. Water and feed were given to the chicks as ad-libitum. Orego-Stim® (0, 300, 500 and 700 ppm) were added into four diets. Body Weight (BW), Body Weight Gain (BWG), Feed Intake (FI), Feed Conversion Ratio (FCR) and death rates were determined in a group level weekly. At the end of experiment, Carcass Yield (CY) and Liver Weigth (LW), Gizzard Weigth (GW), Heart Weigth (HW) and Abdominal Fat (AF) weight were determined cutting all the animals in each group. Orego-Stim® had no significant (p>0.05) effect on BW, BWG and mortality of broiler chicks at all experiment periods whereas Orego-Stim® had significant effect on FI and FCR in the current study. On the other hand, Orego-Stim® hadno (p>0.05) effect on CY, AF, LW, GW and HW.
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This study was conducted to evaluate the effect of garlic (Allium sativum) meal on the intestinal mucosal morphology of broiler chickens between 21 and 42 days of age. A total of 1800, 21 days old Ross 308 broiler chicks were weighed and randomly allotted into 0, 0.125, 0.25, 0.5, 1 and 2% dietary garlic meal groups of each 100 birds. Experimental diets were formulated by addition of each level of garlic meal to commercial finisher mash diet (CP : 20.45%, ME : 3,130kcal/kg), and fed ad libitum for 21d. At day 42, 15 chicks from each treatment were randomly killed to obtain intestinal samples. Villus height, epithelial thickness, goblet cell numbers, crypt depth and the ratio of crypt depth to villus height in each intestinal segment were compared using a light microscope. Garlic meal as a feed additive significantly enhanced villus height and crypt depth and decreased epithelial thickness and goblet cell numbers in duodenum, jejunum and ileum of birds. Fundamentally, jejunum and ileum revealed an almost similar morphological alteration to that in the duodenum except that dietary garlic meal supplement resulted in an increase in the ratio of crypt depth to villus height in duodenum but a decrease in jejunum and ileum. In present study, small intestinal morphological changes in chickens due to dietary garlic meal supplement demonstrate that absorptive process could be activated by garlic meal as an antibiotics alternative growth promoter.
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Two experiments were carried out to assess the efficacy of plant extracts as alternatives for antimicrobial growth promoters in broiler diets. The performance experiment included 1,200 male broilers raised from 1 to 42 days of age. The metabolism experiment used 96 male broilers in the grower phase housed in metabolic cages for total excreta collection. At the end of the metabolism experiment, 24 birds were sacrificed to assess organ morphometrics. In both experiments, the following treatments were applied: control diet (CD); CD + 10 ppm avilamycin; CD + 1000 ppm oregano extract; CD + 1000 ppm clove extract; CD + 1000 ppm cinnamon extract; and CD + 1000 ppm red pepper extract. The microencapsulated extracts contained 20% of essential oil. No significant differences (P>0.05) in the studied performance parameters were observed among treatments. The dietary supplementation of the extracts did not influence (P>0.05) nitrogen- corrected apparent metabolizable energy values. In general, organ morphometrics was not affected by the experimental treatments, but birds fed the control diet had higher liver relative weight (P
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The study was conducted to determine whether dietary supplemental plant extracts could have the potential as alternative growth promoters to antibiotics. One hundred and five, 1-day-old male broiler chicks (Ross 308) were used in the experiment. The animals were allocated into seven dietary treatments groups in a complete randomized design. The groups were as follow: 1. Control (basal diet), 2. Antibiotic (basal diet + 10 mg flavomycin/kg diet), 3. Yucca schidigera (Basal diet + 120 mg Yucca schidigera extract/kg diet) 4. Oreganum vulgare (Basal diet + 120 mg Oreganum vulgare esanstial oil/kg diet), 5. Thymus vulgaris (Basal diet + 120 mg Thymus vulgaris esantial oil/kg diet), 6. Syzigium aromaticum (Basal diet + 120 mg Syzygium aromaticum esantial oil/kg diet), 7. Zingiber officinale (Basal diet + 120 mg Zingiber officinale essential oil/kg diet). Each group was fed ad libitum its own diet for a period of 42 days. The data were analyzed using GLM procedure of SAS (1987). Antibiotics or plant extract supplementation did not influence (P>0.05) body weight gain, feed intake and feed conversion efficiency significantly; however, treatments groups achieved numerically higher performance values. The highest weigh gain was achieved with antibiotic or Z. officinale. The birds receiving Z. officinale also attained the highest carcass weight and abdominal fat weight. The results with respect to cholesterol, triglycerides and glucose showed that cholesterol concentration was not influenced (P>0.05) by dietary treatments, however, glucose concentration was elevated (P<0.05) by Z. officinale, while triglyceride concentration was increased (P<0.05) by Z. officinale and also S. aromaticum. Plant extracts used in the trials also affected weight and length of some part of digestive tract. Especially, supplementation of O. vulgare or Z. officinale or S. aromaticum reduced (P<0.05) total length of digestive tract but increased (P<0.05) weight of jejunum. The results also showed that supplemental Z. officinale increased (P<0.05) the number of lactic acid bacteria in the jejunum. It was concluded that dietary supplemental plant extracts, especially Z. officinale increased growth performance and number of beneficial bacteria. It could be speculated that Z. officinale could be of value to replace antibiotics which have been banned to use as growth promoter in animal feeds.
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This report will review the history of antibiotic growth promoter (AGP) use in the animal industry, concerns about development of antimicrobial resistance, and response in the European Union and United States to these concerns. A brief description of the history of legislation regarding feed use of antimicrobials in Denmark and the experience of animal producers following the 1998 ban will serve to illustrate the consequences on animal performance and health of withdrawing the approval for this use. The biological basis for antibiotic effects on animal growth efficiency will consider effects on intestinal microbiota and effects on the host animal and will use the germ-free animal to illustrate effects of the conventional microflora. The probability that no single compound will replace all of the functions of antimicrobial growth promoters will be considered, and methods to consolidate and analyze the enlarging database will be discussed.
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Present experiment was performed to study the effects of Echinacea purpurea (EP) and Nigella sativa (NS) on broiler performance, carcass and meat quality. Four treatment combinations were prepared: C -control group without any feed or water additive; E -drinking water intermittently supplemented with fermented juice of EP; N -feed supplemented with grounded seeds of NS, and EN -drinking water intermittently supplemented with EP and feed supplemented with NS. No significant treatment effect was observed on weight gain, average daily weight gain, feed conversion ratio and abdominal fat percentage. Carcass yield in C and N groups was significantly (P<0.05) higher than in E. Significantly (P<0.05) higher breast percentage in group N was observed. Crude protein contents were significantly (P<0.05) higher in meat samples of C and EN groups. Grill losses were significantly (P<0.05) lower in E and cooking losses were significantly (P<0.05) higher in N treated birds. No significant treatment effect was observed on meat colour, electrical conductivity and shear force value.
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Antimicrobial compounds produced by microorganisms have been used for decades in poultry diets to increase performance and decrease morbidity particularly in broiler chickens. However, consumer pressure related to the potential development of antibiotic-resistant bacteria has resulted in the development of non-antibiotic feed additives that may also improve broiler performance. In recent years, aromatic plants and their extracts have received attention as growth and health promoters. It is known that most of their properties are due to the essential oils (EOs) and other secondary plant metabolites. EOs enhance production of digestive secretions, stimulate blood circulation, exert antioxidant properties, reduce levels of pathogenic bacteria and may enhance immune status. The purpose of this paper is to provide an overview of the published data on the potential of EOs and their components in poultry nutrition, and to describe their possible modes of action. The current knowledge on potential antagonistic and synergistic effects is presented and areas for future research are proposed.
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The present study was designed to evaluate whether a blend of essential oils (EO) extracted from herbs could affect growth performance, digestive enzymes and antimicrobial activity of the gut in growing broiler chickens. A total of one hundred and twenty, 3-day-old male broiler chickens were assigned to the basal diet (CON) and the basal diet supplemented with 10mgantibiotics/kgdiet (ANTI), 25mgEO/kgdiet (EO I) and 50mgEO/kgdiet (EO II) until 35 days of age. Throughout the entire feeding period (3–35 days), there were no differences in body weight, feed intake, total gain and feed:gain ratio among the birds fed the basal diet and the diet supplemented with antibiotics, either low (EO I) or high level of EO (EO II). Weights of digestive organs including the liver, pancreas, intestine and mucosal tissues were not affected by the dietary treatments. Total and specific activities of pancreatic trypsin significantly (P