Research Article

 

Effect of Hot Red Pepper Oil on the Productivity, Carcass Characteristics and Economic Efficiency of Broiler Chickens

 

Saber S.A. Hassan1, Eman M. El-Ktany2*

1Department of Animal and Poultry Production, Faculty of Agriculture, Damanhour University, Egypt; 2Veterinary Economics and Farm Management, Department of Animal Husbandry and Animal wealth Development, Faculty of Veterinary Medicine, Alexandria University, Egypt.

 

Received | Novvember 17, 2020; Accepted | December 01, 2020; Published | December 27, 2020

*Correspondence | Eman M El-Ktany, Veterinary Economics and Farm Management, Department of Animal Husbandry and Animal wealth Development, Faculty of Veterinary Medicine, Alexandria University, Egypt; Email: [email protected]

Citation | Hassan SSA, El-Ktany EM (2020). Effect of hot red pepper oil on the productivity, carcass characteristics and economic efficiency of broiler chickens. J. Anim. Health Prod. 9(s1): 128-134.

DOI | http://dx.doi.org/10.17582/journal.jahp/2020/9.s1.128.134

ISSN | 2308-2801

Copyright © 2020 Hassan and El-Ktany. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

 

INTRODUCTION

 

In order to increase feed efficiency and body weight gain, growth promoters are usually used as in-feed supplements in broiler feed. They can be categorized as Antibiotic growth promoters (AGP) and Non–Antibiotic growth promoters (NAGP). Antibiotic growth promoters in broiler industry have been used to boost growth efficiency and feed conversion ratios (Dibner and Buttin, 2002; Miles et al., 2006). However, continuous treatment with broiler AGP can result in residues of antibiotics in broiler meat and bacterial resistance against treatments in human body. In several countries the use of AGP in broiler fattening is therefore prohibited (Botsoglou and Fletouris, 2001; Alcicek et al., 2004; Owens et al., 2008). NAGP use on the other hand is typically considered to be acceptable alternatives to AGP, as they normally do not carry any risk of bacterial resistance or unwanted contaminants in broiler meat. Organic acids, probiotics, prebiotics, synbiotics, phytogenics, feed enzymes and immune stimulants are included in NAGP (Valera et al., 2021; Ikele et al., 2020; Deraz, 2018). Phytogenics are drawing much attention nowadays. Phytogenics include antioxidant, antimicrobial, antifungal and antiviral effects and are derived from herbs, spices or aromatic plants (Taylor, 2001). One of the most essential herbs or spices, which is much common, is Red Pepper (Capsicum annuum). Red pepper is rich in vitamins C and E and capsaicin (Lee et al., 2010; Shahverdi et al., 2013). Hot red peppers, also known as chili peppers, owe their “heat” to capsaicin (Shahverdi et al., 2013; Al-Kassie et al., 2011).

 

Approximately 48 percent of the active substances of red pepper are capsaicin (CAP), the most active compound responsible for the pungent effects of hot red peppers (Jancso et al., 1997). Capsaicin is an essential alkaloid and have neurotonic and antimicrobial activity (Fadile and Elife, 2005), as well as may suppress lipid peroxidation effectively (Oboh et al., 2006; Conforti et al., 2007). CAP has many biochemical and pharmacological properties, including antioxidant, anti-inflammatory, anti-allergenic and anti-cancer activities (Lee et al., 2005). CAP was more effective in inhibiting lipid peroxidation than vitamin E (Luqman and Razvi, 2006). It is known to increase pancreatic and intestinal enzymes (Platel and Srinivasan, 2004), bile acids (Abdel et al., 2005) and BWG in broiler chicks (Puvača et al., 2015). Hot red pepper is rich in vitamin C, which lead to the reduction of heat stress (Yoshioka et al., 2001; Al-Kassie et al., 2012).

 

Through managing pathogens, these biotic additives such as Capsicum annuum contribute to the balance of gastrointestinal microbiota. Essential oil extracted from Capsicum annuum has antimicrobial activities against pathogenic bacteria, including Escherichia coli, Clostridium perfringens, and Salmonella enteritidis (Kozukue et al., 2005), and acts as a strong antioxidant, digestive stimulant, anti-inflammatory, and antidiarrheal agent. It increased return energy consumption and suppressed production in the organs (Frankič et al., 2009; Barbero et al., 2010; Traesel et al., 2010). Herbs and herbal extracts and their oils enhance feed consumption, boost digestive enzyme secretion, and trigger immune function, as well as encourage the anthelmintic, antibacterial, antioxidant, and antiviral activities (Abdelnour et al., 2018). Also, increase the production of beneficial bacteria and restrict various pathogenic bacterial activities in the broiler intestine (Langhout, 2000; Wenk, 2000). So, the goals of this study were to evaluate the impact of hot red pepper oil (HRPO) as natural feed additives (FA) on growth performance, carcass traits and economic efficiency of broilers.

 

MATERIALS AND METHODS

 

Birds and management

This work was carried out during the period from November to December 2019 at El-Bostan Farm, Faculty of Agriculture, Damanhur University. Arbor Acres broiler chicks (n=100), 7 days old, were divided among four treatment groups in a completely randomized design with three replicates per treatment and eight or nine chicks per replicate distributed. They were fed iso-caloric and iso-nitrogenous basal diets containing three levels of HRPO i.e., 0.25, 0.5 and 1 ml/ kg diet (T2, T3 and T4 respectively) during the experiment time (7 to35 days). The Control group (T1) was fed only basal diet without any supplementation. HRPO was observed as having 50 mg capsaicin /ml of HRPO.

 

During 7-21 and 22-35 days of age, broilers given a commercial mash diet (Table 1). During the preliminary phase (1-6 days of age), chickens were the same starter feed that provided during 7-21 days. The mean indoor temperatures during the 1st, 2nd, 3rd and 4 weeks of age were 34, 32, 30 and 28°C, respectively. Feed and water were given ad libitum. A 23:1h light-dark cycle was given for chicks. During the experimental process chicks were housed under similar management and hygienic conditions. The trials protocol was approved by the Science and Ethics committee of the Faculty of Agriculture, Department of Animal and Poultry production, Damanhur University.

 

Table 1: Composition of basal diets for studies.

 

Ingredients	Starter diet (1-21 d of age)	Grower diet (22-35 d of age)
Yellow corn, kg	490	550
Soybean meal 48% CP, kg	420	358
Di-calcium phosphate, kg	20	15
Limestone, kg	10	12.5
NaCl, kg	3	3
Vitamin+ premix mineral, kg	3	3
Dl-Methio,nine, kg	2.5	2.5
L- Lysine, kg	1.5	2.0
Vegetable oil, kg	50	54
Total	1000	1000
ME	3035	3135
CP	229	208
Ca	9.5	9.1
Available P	5.2	4.2
Methionine	6.0	5.6
TSAA	9.6	9.1
Lysine	13.7	12.6
Ether extra	47	48
Crude fiber	33	38
Ash	55	52
Dry matter	901	912

 

The Vit+Min blend contains: 24 mg vitamin A (retinyl acetate), 20 mg vitamin E (dl-α-tocopheryl acetate), 2.3 mg menadione, 0.05 mg Vitamin D3 (cholecalciferol), 5.5 mg riboflavin, 12 mg calcium pantothenate, 50 mg nicotinic acid, 600 mg choline chloride, 10 μg vitamin B12, 3 mg vitamin B6, 3 mg thiamine, 1 mg folic acid, 0.50 mg d-biotin. Mineral traces (mg per kg of diet): Mn 80 Zn 60, Fe 35, Cu 8, Se 0.60.

 

A 33.33 percent mixture of soybean oil, cotton seed oil and sunflower.

 

Variables and data

The broilers were weighed (g), and body weight gain (BWG), feed intake, and feed conversion rate (FCR) was calculated at 7, 14, 21, 28 and 35 days of age. Daily recorded mortality. At the end of the experiment (35 days of age), three chicks were randomly selected and weighed to acquire live body weight (LBW) from each replicate. Chicks were slaughtered and feathered. The dressing percentage was measured and the inner organs were individually weighted as a percentage of carcass weight.

 

Economical evaluation were done through calculation of, chick cost (5 LE), Total feed intake /chick (kg), Total feed cost/chick (LE), Price/kg feed (6.7 LE), Fixed cost/chick (1.8 LE), FA cost (LE), Total cost/chick (LE), Price of kg broiler meat at end of the trial (24 LE), Total revenue /chick (LE), and Net margin profit (LE). The economic efficiency evaluation of the HRPO was performed by measuring , FA cost /Total cost%, FA cost /Total return%, Feed intake cost per Kg BWG, Total return/ Total cost% and Net profit/ Total cost%.

 

Statistical Analysis

ANOVA of SPSS/PC+ «version 25» used to conduct the statistical analysis of data. A substantial difference among the means was measured at 5 percent probability levels using Duncan’s multiple range technique.

 

RESULTS AND DISCUSSION

 

Effect of dietary HRPO supplementation on growth performance of broilers

The finding in Table 2 showed that, the addition of different levels of HRPO into broiler diet significantly (p<0.05) enhanced all productive performance parameters in treated groups relative to control group. The supplemented diet with level of 0.5ml HRPO/kg showed significantly (p<0.05) the highest BWG (2302g/bird) and feed intake (3427g/bird) with best FCR (1.49) among all treatments. Our results can be illustrated by the work of Herati and Marjuki, (2011) where they reported that, the pungent compound of hot red pepper increases the production of saliva and gastric secretion. Such digestive enzymes activate liver to secrete bile, which further digests food substance. In addition hot red pepper has been reported to encourage digestion and absorption of feed in the digestive tract (Afolabi et al., 2017). Both capscacinoids and capsaicin from pepper were reported to increase body temperature, consumption of oxygen and promote energy metabolism. The capsaicin in hot red pepper was involved in a stimulant, antiseptic and digestive effect that improved metabolism of carbohydrates by stimulating the sympathetic nervous system. The rise in energy or carbohydrate metabolism would improve the development of more tissues and weight gain or growth (Afolabi et al., 2017).

 

Table 2: Impact of HRPO dietary supplementation on growth performance (at 7-35 days) of broiler chickens.

 

Variables	Control (T1)	Hot red pepper oil (HRPO)
		0.25ml/kg (T2)	0.5ml/kg (T3)	1ml/kg (T4)
Initial live weight (g/bird)	141.4± 3.39	141.6± 3.86	142.2± 2.64	141.3± 3.30
Final body weight (g/bird)	2279± 26.73d	2316± 24.58c	2444± 30.76a	2385± 29.57b
Body weight gain (g/bird)	2138± 29.37d	2174± 66.78c	2302± 40.03a	2244± 30.85b
Total feed intake (g/bird)	3407± 60.06b	3361± 97.80c	3427± 31.19a	3325± 78.84d
Feed conversion ratio	1.59± 0.02a	1.55± 0.02b	1.49± 0.03c	1.48± 0.03c

a-d Means with different superscripts within the same row are substantially different at (p<0.05).

 

Effect of dietary HRPO on carcass yield, dressing percentage and relative weight of internal organs

The carcass characteristics and internal organs (expressed as percentage of live weight) of broilers fed diets with different HRPO levels were presented in Table 3. In all experimental groups, the addition of various amounts of HRPO to broiler diets significantly (p<0.05) improved dressing percentage. Birds fed on a diet containing a dietary level of 0.5ml HRPO /kg diet showed the highest (p<0.05) dressing percentages (76.3%), as compared to the control group that had the lowest dressing percentages (75.29%). Our dressing percentage findings are similar to previous reports (Shahverdi et al., 2013; Al-Kassie et al., 2011), where they recorded a dressing percentage ranging from (70.11– 74.30%) by supplementing the broilers with 0.02 – 1.00 percent hot red pepper and black pepper enriched diet for six weeks. Our finding also agreed with those of

 

Table 3: Effect of HRPO dietary supplementation on carcass yield, dressing percentage and certain internal organs as a proportion of broiler final live weight.

 

Traits	Control (T1)	Hot red pepper oil (HRPO)
		0.25ml/kg (T2)	0.5ml/kg (T3)	1ml/kg (T4)
Live body weight, g	2792±51.34c	2778±56.00d	2940±76.54a	2813±180.84b
Carcass weight, g	2102±26.19b	2100±32.79c	2243±63.53a	2123±145.90b
Dressing, %	75.29±0.59c	75.6±0.44b	76.3±0.21a	75.5±0.38b
Proventriculus, %	0.29±0.02	0.33±0.01	0.28±0.03	0.28±0.02
Gizzard, %	1.28±0.04a	1.13±0.10b	1.02±0.16c	1.17±0.10b
Liver, %	1.84±0.06c	2.07±0.19b	2.24±0.04a	1.89±0.09c
Heart, %	0.44±0.01	0.45±0.01	0.42±0.03	0.41±0.02
Spleen, %	0.07±0.01c	0.13±0.35a	0.07±0.001c	0.09±0.006b
Intestine, %	3.5±0.09	3.89±0.11	3.97±0.20	3.7±0.15
Pancreas, %	0.19±0.006c	0.22±0.009a	0.20±0.005b	0.20±0.002b
Abdominal fat, %	1.34±0.08b	1.54±0.30a	0.93±0.18c	1.26±0.17b
Bursa, %	0.17±0.01c	0.25±0.05a	0.20±0.01b	0.22±0.03b
Thymus, %	0.39±0.04c	0.49±0.04a	0.41±0.04b	0.40±0.03b

a-d Means with different superscripts within the same row are substantially different at (p<0.05).

 

Table 4: Effect of HRPO dietary supplementation on overall expenses, total return and net benefit for the study groups (Egyptian pound (LE)/Bird).

 

Traits	Control (T1)	Hot red pepper oil (HRPO)
		0.25ml/kg (T2)	0.5ml/kg (T3)	1ml/kg (T4)
Feed intake costs	22.8±0.42 b	22.5±0.97 c	23.0±0.22 a	22.3±0.73 d
Additive costs (HRPO)	0	0.49±0.02c	1.03±0.01b	1.99±0.07a
Chick costs	5.00	5.00	5.00	5.00
Management costs	1.80	1.80	1.80	1.80
Total costs/bird	29.6±0.42c	29.79±0.98d	30.83±0.22b	31.1±0.80a
Broiler weight gain/bird	2138±29.37d	2174±66.78c	2302±40.03a	2244±30.85b
Broiler sale/bird	51.3±0.72d	52.2±0.63c	55.3±0.92a	53.8±0.75b
Total return/bird	51.3±0.72d	52.2±0.63c	55.3±0.92a	53.8±0.75b
Net profit/bird	21.7±0.57d	23.1±0.70b	24.5±0.97a	22.8±0.57c

a-d Means with different superscripts within the same row are substantially different at (p<0.05).

 

Abd EL-Haliem, (2019) who stated that, the inclusion of hot red pepper (HRP) in diet resultad in substantial variations (p≤0.05) observed in relative weights of dressing, carcass and offal.

 

All the measured variables for internal organs (expressed as percentages of live body weight) were statistically improved (p<0.05) with the exception of the heart and intestine (Table 3). Compared to the control diet, the addition of HRPO to broiler diets noticeably (p<0.05) increased percentages of liver, spleen, pancreas, bursa and thymus. The group fed 0.5ml HRPO/kg diet recorded significantly (p<0.05) the highest liver percentage (2.24%) and the lowest abdominal fat percentage (0.93%), as compared to those of liver percentage (1.84%) and abdominal fat percentage (1.34%) recorded for control group. Our results for internal organs may be due to capsaicin in HRPO meal which is pungent or pepperish; it could have challenged the body which in turn stimulated the production of more leucocytes or antibodies that can fight foreign bodies and diseases when the need arises. This would improve the bird’s ability to combat pathogens and thus their anti-pathogenic or antibacterial properties (Al-Kassie et al., 2012) and this may be the explanation for the increase in percentages of relative weight of liver, spleen, pancreas, bursa and thymus.

 

The addition of HRPO to broiler diets also, reduce the abdominal fat percentage substantially (p<0.05) as exhibited in Table 3. Our findings align with those of Puvača et al.,

 

Table 5: Economic efficiency evaluation of HRPO in broiler diet as a natural feed additive (FA).

 

Traits	Control (T1)	Hot red pepper oil (HRPO)
		0.25ml/kg (T2)	0.5ml/kg (T3)	1ml/kg (T4)
FA cost/Total cost, %	0	0.02±0.00c	0.03±0.00b	0.06±0.00a
FA cost/Total return, %	0	0.01±0.00c	0.02±0.00b	0.04±0.00a
Feed intake cost per Kg BWG	10.65a± 0.04	10.32 b ±0.46	9.98c±0.78	9.92d±0.56
Total return/Total cost, %	1.73±0.02b	1.79±0.02a	1.80±0.03a	1.73±0.02b
Net profit/ Total cost, %	0.73±0.02b	0.79±0.02a	0.80±0.03a	0.73±0.02b

a-d Means with different superscripts within the same row are substantially different at (p<0.05).

 

(2015) where they documented that, hot red pepper (Capsicum annuum L.) plays an important role in mitigating the cholesterol and fat deposition in the body, contributes to decreased triglycerides levels and manage lipid metabolism in a detrimental way to prevent atherosclerosis or coronary heart diseases in people who use chicken products in their regular diet.

 

Effect of HRPO supplementation on overall expenses, total return and net benefit

The findings obtained from the assessment of the economic component of the experiment were presented in Table 4. It showed a substantial increase in feed costs and total costs (p < 0.05) with an increase in dietary HRPO levels. Total costs of feed (feed intake costs + FA cost) ranged from 22.8 – 24.29 Egyptian pound (LE) /bird for control group and those fed diets with 1ml HRPO/Kg diet, respectively. While, total costs (LE/bird) ranged from 29.6-31.1 for control group and those fed diets with 1ml HRPO/Kg diet, respectively. All treated groups with HRPO showed the highest return and net profit compared to the control group. Total return (LE/bird) ranged from 51.3-55.3 for control group and those fed diets with 0.5ml HRPO/Kg diet, respectively. Net profit (LE/bird) ranged from 21.7-24.5 for control group and those fed diets with 0.5ml HRPO/Kg diet, respectively. Our results agreed with those of Abd EL-Haliem, (2019) where he reported the highest return and net profit achieved by treated groups with HRP than those of control group in growing Japanese quails. Diet containing 0.2% HRP recorded the highest net profit.

 

Economic efficiency Evaluation of HRPO in broiler diet as a natural feed additive (FA)

Evaluation of economic efficiency of dietary supplementation of extracted hot red pepper oil is shown in Table (5). The cost of feed additive (HRPO) used in experiment in comparison with total costs and total return were very little. The increase in production costs with the addition of HRPO to the chickens’ diet compared to chickens without natural additive supplementation is negligible, These can be explained as by very little additional costs to broiler diet we can get a significant increase into return and net profit of broiler fattening project (economically efficient). Also, costs of feed intake per kg BWG differed significantly at (p<0.05). For birds fed control diets, the highest cost of feed intake per Kg BWG (10.65 LE) was obtained, whereas for birds fed with 1 ml HRPO/kg diet, the lowest feed intake cost per Kg BWG was obtained.

 

The return and net profit from each Egyptian pound invested in broiler fattening in the three experimental groups is higher than that of control group. The highest return from each invested pound (1.80%) and highest net profit from each invested pound (0.80%) recorded in birds fed diet contain 0.5ml HRPO /kg. Diet contain 0.5ml HRPO /kg considered the most economically efficient diet as it recorded the highest final live body weight and the highest return and net profit for each Egyptian pound invested into broiler chicks fattening.

 

Our findings are consistent with those of Afolabi et al., (2017) where the cost of feed intake per kg BWG also increased significantly (p<0.05). For birds fed control diet, the highest cost of feed intake/kg BWG (₦292.80) was obtained, whereas for those fed diets with 0.2% hot red pepper meal, the lowest cost of feed intake/kg BWG (₦273.6) was obtained.

 

Conclusions

 

Inclusion of 0.5ml to 1ml/kg hot red pepper oil in broilers’ diet increased their production efficiency at a lower cost and had no adverse effect on broiler carcass and their internal organs. Thus, HRPO could be used in broilers’ diet as a replacement of antibiotic growth promoters as it has improving effect on broilers’ performance and economic efficiency. Due to a natural source, it could be hypothesized that inclusion of HRPO will not have any deleterious effects on meat quality of broilers. However, further research on its’ effects on meat quality (like technological and sensory) should be investigated.

 

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