Effect of Liquorice (Glycyrrhiza glabra) on Growth Performance, Gut Morphometry and Economics of Broilers Production

Ashiq Ullah1, Sarzamin Khan1, Muhammad Shuaib1*, Sohaib ul Hassan2, Abubakar Sufyan3, Kinkpe Lionel5, Muhammad Shahkar Uzair1, Majid Ali1, Aamir Khan4, Qudrat Ullah2 and Waqar Azeem6

1Department of Poultry Science, Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture, Peshawar, Pakistan

2College of Veterinary Sciences, Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture, Peshawar, Pakistan

3Department of Livestock and Poultry Production, Bahauddin Zakariya University, Multan, Pakistan.

4Directorate General (Research), Livestock and Dairy Development Department, Khyber Pakhtunkhwa, Peshawar.

5Department of Livestock Management, Breeding and Genetics, Faculty of Animal Husbandry and Veterinary Sciences, The University of Agriculture, Peshawar, Pakistan

6Department of Pathology, University of Veterinary and Animal Sciences, Lahore.

ABSTRACT

This study was conducted to examine the effect of liquorice (Glycyrrhiza glabra) extract on growth performance, gut morphometry, and economics in broilers. One hundred and twenty days old broiler chicks were used for the experiment and were divided into four groups each with three replicates of ten birds. Group 1 was control with normal water while 1, 1.5, and 2ml/liter of liquorice extract (LE) in drinking water were provided to the remaining three groups. The results showed significantly reduced feed consumption, increased weight gain, and better FCR in 2ml/l of LE group. Similarly, 2ml/l of LE group showed increased (P<0.05) villus height, crypt depth, villus width, and villus height to crypt depth ratio. The digestibility of dry matter, ash, crude fiber, crude protein, ether extract, and calcium was also calculated significantly higher in the 2ml/l of LE group. Total cost in the control group while the gross and net return was recorded significantly higher in the group containing 2ml/l of LE. The dressing percentage had a significantly higher value in 1.5, and 2ml/l of LE groups than in the remaining treatment groups. Mortality was recorded significantly higher in 1 ml/l of LE group as compared to all other groups. It was concluded that liquorice extract at 2ml/l water has a useful effect on growth performance, gut morphology, and economics in broilers.

Article Information

Received 27 December 2022

Revised 18 January 2023

Accepted 11 February 2023

Available online 01 May 2023

(early access)

Published 01 July 2024

Authors’ Contribution

AU, SK: Study design, feed formulation, animal trial, laboratory experiment, statistical analysis, and writing. MS, SUH, AS, MSU, KL: Data analysis and evaluation, manuscript writing, and review. MA, AK, QU, WA: Manuscript writing and manuscript review.

Key words

Glycyrrhiza glabra, Performance, Morphometry, Broilers, Economics

DOI: https://dx.doi.org/10.17582/journal.pjz/20221227071205

* Corresponding author: shoaibwzr@gmail.com

0030-9923/2024/0005-2039 $ 9.00/0

Copyright 2024 by the authors. Licensee Zoological Society of Pakistan.

This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

INTRODUCTION

Medicinal herbs, spices, and aromatic plants play essential roles in making food taste, smell, and look better and also have health benefits for people and animals (Abd-El-Hack and Alagawany, 2015; Abd-el-Hack et al., 2018, 2020a, b). Individuals in the livestock industry are becoming more interested in these plants because they have qualities that can improve the quality of the final products from poultry, such as the carcass and meat quality (Abdelnour et al., 2018; Alagawany et al., 2018a, b; Saeed et al., 2018; Velmurugan et al., 2018). This article is about Glycyrrhiza glabra, a member of the Fabaceae (legume) family. It has been used for over 4,000 years in traditional medicine (Shebl et al., 2012). Liquorice has been reported to have immunomodulatory, antihelicobacter, antimicrobial, antioxidative, anti-atherosclerotic, antifungal, anti-inflammatory, estrogen-like, antiviral, antinephritic, anti-infective, and radical scavenging properties (Myandoab and Hosseini, 2012; Alagawany et al., 2018; Seidavi et al., 2021). The main components of liquorice extract (LE), according to phytochemical analysis, are flavonoids (like liquiritin, formononetin, and isoflavonoids), triterpene saponins (like glycyrrhetinic acid, glycyrrhizin, and licorice acid), starch, sugars, amino acids, tannins, ascorbic acid, choline, phytosterols, and coumarins (Shalaby et al., 2004). Researchers (Račková et al., 2007; Suchitra and Shakunthala, 2014; Parvaiz et al., 2014; Alagawany et al., 2019a) have found that liquorice and its active ingredients have several pharmacological effects on livestock like immunomodulatory, antioxidant, antiviral and anti-inflammatory activity. Adding liquorice to the diets of chickens has been shown to make them more productive, however, adding liquorice to drinking water is still in its early stages and needs to be investigated more. Therefore, this study was conducted to determine the effect of liquorice (Glycyrrhiza glabra) extract on growth performance, gut morphometry, and economics in broilers.

MATERIALS AND METHODS

Collection and processing of Glycyrrhiza glabra

The experiment was carried out at the Department of Poultry Science and samples analysis was performed at the pathology laboratory of the College of Veterinary Science, Faculty of Animal Husbandry and Veterinary Science, the University of Agriculture Peshawar. Liquorice roots were purchased from the local market and identified by the medicinal plant experts in the Department of Botany at the University of Peshawar. The method described by Myandoab and Hosseini (2012) and Hanafy (2022) was followed with a few modifications for the processing. The liquorice roots were dried and ground into powder before being used for extraction. After that, four grams of the final product were suspended in 100ml of sterile distilled water, maintained at 37°C for 24 h, and then incubated for eight h at room temperature while being mixed by a magnetic mixture. In the next step, the suspension was kept at room temperature for 18 h. The finished mixture was filtered through a 0.45µL filter and stored at 4°C until needed (Ghannad et al., 2014).

Experimental design and diets

A total of 120 days old broiler chicks were obtained from the local market for the research trial. The birds were split into four groups each with three replicates and ten birds per replicate. Group 1 was control only with normal water without the addition of LE while the other three groups were offered with 1ml/l, 1.5 ml/l, and 2ml/l, respectively, of LE in drinking water. Based on the NRC (1994), the experimental basal diet was made to meet the requirements of broilers. The feed and water were given ad-libitum to the experimental birds from days 1 to 35. The light was provided for twenty-four h. The duration of the experiment was five weeks. Biosecurity was maintained for all the animals to prevent the spread of illnesses e.g., visitors were not allowed, wild animal protection, etc.

Data collection

Feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR) were calculated according to the formula used by Shuaib et al. (2022a). Mortality was recorded on daily basis. Post-mortem examinations of dead birds were performed to rule out any disease or lesions. The dressing percentage was calculated with the help of the formula e.g.,

Dressing percentage= dressed weight/live weight x 100

The nutrient digestibility was calculated according to the procedure explained by Shuaib et al. (2022a, b) and Hafeez et al. (2020). Two chicks from each treatment were collected at five weeks and maintained in a separate cage for feces collection and digestibility testing. Fresh morning faces were collected, weighed, and dried for three days. The dried excreta were analyzed, and then the digestibility was calculated. The following formula was used to determine nutrient digestibility:

Apparent nutrient digestibility (%) = nutrient intake – nutrient output/ nutrient intake × 100.

Gut morphometry was determined according to the method explained by Shuaib et al. (2022). A bird from every replicated group was randomly selected on the last day of the experiment and slaughtered. After that, its gastrointestinal tract was removed. A small piece was cut from the ileum portion of the small intestine and was used for the morphological measurement. Input and out costs were worked out to determine the economic parameters.

Statistical analysis

A completely randomized design (CRD) was used to assess the experimental data. Analysis of variance (ANOVA) was performed using software statistics 8.1. The Graph Pad Prism 8 software (San Diego, CA, USA) was used to make histograms.

RESULTS

Results regarding the effect of the addition of liquorice in water on FI, BWG, and FCR are shown in Table I. FI had a significantly higher value in the control group while the BWG and FCR (better) were calculated significantly higher in the 2ml/l of LE group. The effect of LE on-dressing percentage is presented in Figure 1. 1 ml/l of LE group produced a significantly higher dressing percentage, though not significantly different from group containing 2ml/l of LE.

 

Table I. Effect of liquorice (Glycyrrhiza glabra) in water on feed intake, weight gain and feed conversion ratio in broilers. The values are in Mean±SD.

Parameters	Week	Control	Liquorice treatments			P value
			1.0 ml/l	1.5 ml/l	2 ml/l
Feed intake (g)	2nd	395.7±4.04	391.6±4.43	388.4±4.47	384.8±4.97	0.103
	3rd	645±2.57a	640.4±2.33ab	635.8±2.92bc	631.5±2.37c	0.001
	4th	861.4±3.40a	858.4±2.75ab	853.4±2.43bc	849.2±2.91c	0.003
	5th	1030±2.87a	1025.1±2.99a	1017±2.83b	1009.7±2.37c	0.000
	Overall	2932±2.32a	2915.6±2.25b	2894.3±2.69c	2875±2.74d	0.000
Weight gain (g)	2nd	283.1±3.00b	284.7 ± 3.42ab	287±2.93ab	289.7±3.50a	0.149
	3rd	385.0±2.88b	387.2± 2.83b	389.5±3.33ab	393.5±2.23a	0.031
	4th	473.1±2.93c	475.0±2.88bc	479.1±2.96ab	482.1±2.89a	0.021
	5th	561.1±2.94c	564.1±2.95bc	568.5±3.40ab	573.2±2.89a	0.006
	Overall	1701.5±2.99d	1711±2.87c	1723.7±3.39b	1738±3.49a	0.000
FCR	2nd	1.39±0.06	1.37±0.02	1.35±0.03	1.32±0.03	0.217
	3rd	1.67±0.03a	1.65±0.02a	1.63±0.02ab	1.60±0.02b	0.029
	4th	1.82±0.02a	1.80±0.03ab	1.78±0.01bc	1.76±0.01c	0.026
	5th	1.83±0.03a	1.81±0.03ab	1.78±0.01bc	1.76 ±1.14c	0.034
	Overall	1.72±0.01a	1.70±1.13a	1.67± 0.01b	1.65±0.01b	0.002

 

The values in the same row that don’t have the same superscript differ (P<0.05).

 

 

Similarly, there was no significant difference between the yield of control and 1.5ml/l of LE group, even though control group yield was lower than all the other groups. The impact of adding liquorice in water on nutrient digestibility is presented in Table II. The digestibility of dry matter, ash, crude fiber, crude protein, ether extract, and calcium was calculated significantly higher in 2ml/l of LE group. The results related to the intestinal histomorphology and economics are indicated in Table III. The results show that birds’ intestinal ileum morphology is affected significantly by the administration of liquorice water. 2ml/l of LE group showed increased (P<0.05) villus height, crypt depth, villus width, and villus height to crypt depth ratio than the remaining groups. Gross return and net return per chick were calculated significantly higher for group containing 2ml/l of LE. Results regarding the bird’s mortality are shown in Figure 2. The highest significant mortality of the birds was calculated in 1ml/liter of LE group as compared to all other groups.

 

Table II. Effect of liquorice (Glycyrrhiza glabra) in water on nutrient digestibility in broilers. The values are in Mean±SD.

Parameters	Control	Liquorice treatments			P value
		1.0 ml/l	1.5 ml/l	2 ml/l
DM	62.34±3.39c	66.36±3.49bc	71.40±3.42ab	75.39±3.48a	0.012
Ash	43.40±3.44b	45.37±4.48b	49.33±3.44ab	53.49±3.29a	0.042
CP	56.33±3.39b	59.65±4.08ab	61.45±3.34ab	65.44±3.48a	0.145
CF	62.51±2.49b	65.40± 3.29b	67.35±2.45ab	72.47a±3.38	0.018
EE	53.37±3.49b	57.48±3.43ab	59.34±2.43a	61.97±2.94a	0.049
Ca	28.71±3.99b	32.75±3.69ab	33.37±2.39ab	37.35±4.12a	0.073

 

The values in the same row that don’t have the same superscript differ (P<0.05). DM, dry matter; CP, crude protein; CF, crude fibre; EE, ether extract; Ca, calcium.

 

Table III. Effect of liquorice (Glycyrrhiza glabra) in water on intestinal morphology (ileum) and economic in broilers. The values are in Mean±SD.

Parameters	Control	Liquorice treatments			P value
		1.0 ml/l	1.5 ml/l	2 ml/l
Villus height (µm)	1275.4 ±1.4d	1297.3±1.40c	1311.3 ±1.40b	1325.4 ±1.40 a	0.001
Crypt depth (µm)	212.3±6.41c	204.3±5.03b	195.67±5.42ab	183.34±5.03a	0.001
Villus width (µm)	168.0±5.54b	177 ±6.48b	189.40±6.48a	199.7±5.93a	0.001
Villus height: Crypt depth	6.31±1.41b	7.52 ±1.30b	8.34 ±1.36ab	10.41±1.41a	0.035
Cost (Pak Rs)	345.49±2.43a	339.40±2.43b	333.54±2.37c	327.4±329d	0.001
Gross return (Pak Rs)	370.18±2.09c	374.85±1.38b	379.20±1.94a	381.5±1.55a	0.001
Net return (Pak Rs)	24.60±2.43d	35.46±2.41c	45.58±2.39b	54.42±2.26a	0.002

 

The values in the same row that don’t have the same superscript differ (P<0.05).

 

DISCUSSIONS

The current study indicated significantly improved feed intake, body weight gain, and FCR in the liquorice-supplemented groups. On the other hand, the feed intake and corresponding weight gain were significantly decreased in the control group. Indeed, due to its chemical components, liquorice acts as an immunomodulator (due to its low molecular weight exhibit anticancer and immunomodulatory activities by suppressing tumor growth) and maintains the correct gastrointestinal status, increasing the animal’s immune system (Alagawany et al., 2019a, b), thus improving growth performance of birds. Therefore, the beneficial effects of phytogenic extracts on poultry growth in this study may be due to the ability of liquorice to improve digestibility, gut microflora, and digestive enzyme secretion. Similarly, Grieve (2013) reported that liquorice stimulates appetite and digestion and improves blood flow through gut mucous membranes, boosting nutrient absorption. Hosny et al. (2020) in quail, and Hassan and Lashin (2017) in chicken found that the body weight of the study animal improved as the quantity of licorice in its diet went up, compared to the control group. Also, Al-Daraji (2012) found that adding LE to drinking water at a level of 450 mg/l increased body weight gain and total body weight by a lot. Furthermore, Al-Daraji (2012) found that adding different amounts of licorice powder to the diets of broilers led to much more weight gain than in the control group. On the other hand, some research showed that the body weight of birds that used licorice or drank water with licorice did not change much compared to the body weight of untreated birds (Moradi et al., 2014; Naser et al., 2017). In the current study, the highest feed conversion ratio value and the dressing percentage, was observed in the group with 2ml/l liquorice in water and this may be because the liquorice root powder supplement in the water made the water taste better the animals, which probably increased the activity of microorganisms in the chicken’s digestive tract. This, in turn, made it easier for the animals to eat dry matter in the experiment, which made the beneficial bacteria work more effectively (Meng et al., 2006). The food conversion efficiency indicated that it is the active substance in this plant, which led to increased animal feed and body weight utilization and, therefore, feed conversion (Muhammad and Oloyede, 2010). This is in agreement with Towaje et al. (2020) who showed that using 7.5% raw liquorice powder improved chicken’s feed ratio and dressing percentage and the same author also found that the licorice powder improved the chemical analysis of meat by more moisture and less fat. Al-Daraji study illustrated that Fawbro broiler chicks receiving drinking water with 450mg/l liquorice extract significantly increased the dressing percentage when measured with or without giblets.

Similarly, Alagawany et al. (2019) found that due to the presence of active molecules, particularly those of the isoflavonoid class of chemicals, liquorice may be able to enhance the function of the immune system. In the current study, ash content, dry matter, and crude fiber were found significantly higher as compared to the control group. The only justification for this improvement may be that liquorice supplemented in animal rations may stimulate cellulose-degrading bacteria, thus, increasing crude fiber digestibility. This result is consistent with the previous findings (Hassanat et al., 2017; Benchaar et al., 2007; Hassan and Abdel-Raheem, 2013; Wei et al., 2016), who reported improved crude fiber digestibility in their studies. Additionally, Akanmu and Hassen (2017) determined that plant extracts improved the digestibility of fat and overall dry matter. The glycyrrhizin found in Glycyrrhiza glabra is considered to stimulate mechanisms of peripheral sensory innervation in the cavities of the nose and mouth. It stimulates the gastrointestinal tract (GIT) to receive the feed and motility of the GIT and secretions of the stomach for better digestion of diet ingredients (Kheravii et al., 2018). From these data, it could be observed that the beneficial impact of liquorice in improving feed efficiency and digestion could be through providing a better environment for the absorption of nutrients, thus, the improvement of dry matter, ash content. Regarding the economic part, the supplementation of Glycyrrhiza glabra in drinking water was found to be beneficial for the group who received it in the current study. This positive effect may be attributed to the significant positive effects on daily weight gain and feed conversion ratio throughout the growing period. Indeed, the chicken industry’s biggest concern is epidemiological diseases, which mostly affect the respiratory, digestive, and immunological systems cause diseases in them and increase the cost per chick by controlling the disorders (Hafez and Attia, 2020). Flavonoids and glycyrrhizin are two bioactive components that are effective in treating disorders such as the liver, immune system, and lungs (Alagawany et al., 2019b). Hence controlling the diseases using liquorice (Glycyrrhiza glabra) in the water reduces the cost and increases the net return (Saeed et al., 2019).

CONCLUSION AND RECOMMENDATION

It is concluded from the current study that liquorice extract at 2ml/l drinking water reduced feed consumption, increased weight gain, improve FCR, and enhanced ileum morphology and was also feasible economically. Therefore, liquorice extract at 2ml/l in drinking water is recommended for broiler production.

ACKNOWLEDGMENT

I would like to express my gratitude to my primary supervisor, Professor Dr. Sarzamin Khan, who guided me throughout this project. I would also like to show my deep appreciation to my supervisory committee who helped me to finalize my project. The research work is part of the MSc (HONS) degree program and is self-supported.

Funding

No funding was provided/ received for this experimental work.

IRB approval

The experimental work was approved by the board of studies (September 2022) conducted at the Department of Poultry Science, Faculty of Animal Husbandry and Veterinary Sciences (FAHVS), The University of Agriculture Peshawar, KP, Pakistan.

Ethical statement

The experiment was approved by the ethical committee of the Faculty of Animal Husbandry and Veterinary Sciences (FAHVS), The University of Agriculture Peshawar before practical execution of this experiment.

Statement of conflict of interest

The authors have declared no conflict of interest.

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