Dose titration of herbs mixture powder supplementation on laying performance and egg quality in commercial layer chicken

M A Rahman, D Ray, M R A Redoy and M Al-Mamun

Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh
mamamun@bau.edu.bd

Abstract

This study was conducted to assess the effectiveness of herbs powder mixture (HPM) supplementation at different levels on laying performance and egg quality of layer chicken. A total of 300 commercial laying hens (Lohman Brown) aged 32 weeks were randomly distributed into five groups and five replicates (12 birds/replicate) in completely randomized design for a period of 8 weeks. Experimental groups were formed according to the level of HPM supplementation (g/kg of basal ration) i.e., HPM0 (control), HPM5, HPM10, HPM15, and HPM20. The HPM was comprised of 90% plantain (Plantago lanceolata L.), 5% ivy-gourd (Coccinia grandis), 3% garlic (Allium sativum) and 2% spearspearmint (Mentha spicata) leaves. Feeding HMP improved the feed intake, HDEP, egg mass and FCR and egg yolk color.

Keywords: egg mass, feed conversion ratio, hen day egg production, Plantago lanceolata, yolk color

Introduction

Antibiotic growth promoters (AGPs) were introduced to livestock industry to improve the animal productivity but in 2006 European Union banned the AGPs in livestock feed industry due to its negative consequence in human health that cause anti-microbial resistance (AMR). Therefore, as an alternative to AGPs, prebiotic, probiotic, enzymes and phytobiotic have recently gained much attention, whereas phytobiotic have been examined to be safe, economic, and less hazardous among all feed additives in livestock industry (Qureshi et al 2016). Phytobiotic refers to natural herbs, spices and their extract that used as non-nutritive products in poultry nutrition to elevate the performance, and products quality (Windisch et al 2008). Phytobiotic improved feed utilization by increasing the secretion of enzymes from digestive tract and liver (Hernandez et al 2004; Prakash and Srinivasan 2010; Abou-Elkhair et al 2014) due to its antioxidants, antimicrobial and anti-inflammatory activities (Windisch et al 2008; Gheisar and Kim 2017). Phytobiotic possesses phytochemicals like polyphenols, glycosides, tannins, and saponins which have positive impact on poultry along with human health but overdose might lead to reduce feed intake, nutrients absorption, bone formation and poisoning not only in poultry (Ebrahim et al 2015) but also in human (Lorent et al 2014).

A herbs mixture powder was developed by taking consideration of phenolic, flavonoid contents, biomass yield and availability which possess 90% plantain (Plantago lanceolata L.), 5% ivy-gourd ( Coccinia grandis), 3% garlic (Allium sativum), and 2% spearspearmint (Mentha spicata) leaves. Plantain herb has been used as human tonic, and forage herb for ruminants and poultry (Fons et al 2008; Camy et al 2019; Redoy et al 2020) which exerts anti-microbial, anti-oxidative, anti-inflammatory, anti-parasitic effects in poultry (Hausmann et al 2007; Ferrazzano et al 2015; Boamah et al 2016), due to its bioactive components. In addition, plantain has higher capability to scavenge the free radicals (Al-Mamun et al 2007) that might reduce the oxidation leading to raise the yolk color. Ivy-gourd, a tropical herb native to the cucurbitaceae family which is rich source of flavonoids, glycosides, phenols, alkaloids, terpenoids and tannins that showed the antioxidants properties (Ashwini et al 2012), anti-inflammatory activity (Deshpande et al 2011), and hepato-protective activity (Anil Kumar 2012). The garlic leaves have been used as phytogenic feed additive both in ruminants (Redoy et al 2020) and non-ruminants (Camy et al 2019), and acts as an antioxidant, antiviral, antibacterial, antifungal as well as growth promoting agent due to diallyl sulphides, alliin, allicin, flavonoids, saponins and fructans (Sivam 2001; Amagase et al 2001). Spearspearmint is an aromatic herb that has been used in broiler and layer production due to its antioxidant, antibacterial, antiviral, antifungal, insecticidal properties (Gulluce et al 2007; Abu Isha et al 2018; Mehran Torki et al 2020).

So, the goal of the study to find out optimum inclusion level of herbs powder mixture in layers to improve laying performance and egg quality. In addition, evaluating the synergistic interaction among plantain, ivy-gourd, garlic and spearspearmint leaves powder in a mixture form in layer ration as phytobiotic which might be mentioned as novelty of present research.

Materials and methods

Experimental ethics

The experimental procedures, bird handling, and egg samples collection have been reviewed and approved by the Animal Welfare and Experimental Ethics Committee of Bangladesh Agricultural University (BAURES/ESRC/2020/AH/23).

Experimental design, diets, housing and management

At 32 weeks, 300 laying hens with similar body weight were randomly allocated to five treatments with five replicates and 12 birds/replication in a completely randomized design until 40 weeks (experimental period 8 weeks). The laying birds were offered a maize -soybean based ration in mash form as basal ration. The ingredients with percent and calculated and analysed chemical composition of basal ration were shown in Table 1.

The treatments were HPM0, HPM5, HPM10, HPM15, and HPM20 in which 0, 5, 10, 15, and 20g herbs powder mixture (HPM) were supplemented with per kg basal ration, respectively and HPM0 was taken into consideration as control. The HPM was prepared by 90% plantain (Plantago lanceolata L.), 5% ivy-gourd (Coccinia grandis), 3% garlic (Allium sativum) and 2% spearmint (Mentha spicata) leaves that were dried under shade at 30-35⁰C with artificial ventilation system. The plantain, ivy-gourd, spearmint and garlic herbs were cultivated at Forage Herbs Bank, Shahjalal Animal Nutrition Field Laboratory under the Department of Animal Nutrition that was harvested at 65 days, just prior to flowering stage, at mature stage, and during harvesting of garlic cloves, respectively. The proximate components, calcium, phosphorus, total phenolic and flavonoids of plantain, ivy-gourd, spearspearmint and garlic leaves were presented in Table 2.

Clean water was provided ad libitum during the experiment, whereas about 122 gram feed was supplied to a bird in a day at two times. Hens were housed in open sided equipped with feeders and nipple drinkers. In a day, hens were reared under a 16 hour light and 8 hour dark (2200 to 0600) condition. The laying hens were kept in optimal and standard temperature.

Record and sample collection

A total of 30 eggs/treatment (6 eggs/replication) were taken weight daily basis for measuring the egg weight, egg mass, and feed conversion ratio (FCR). Every day, egg from each treatment was counted for hen day egg production (HDEP) and feed intake was measured. At the end of 40th week, a total of 30 eggs/treatment were collected and brought to Animal Nutrition laboratory for further analysis within 24 hours maintaining room temperature.

Sample analysis

Feed and herbs samples analysis

The proximate components of basal ration and shade dried herbs including plantain, ivy-gourd, spearmint and garlic was determined according to AOAC (2005). Besides, calcium and phosphorus contents of basal ration and shade dried herbs were determined using a UV spectrophotometer (T60; PG Instruments, UK). Total phenolic content of shade dried herbs were measured with the folin ciocalteau assay using gallic acid standard (Sigma Aldrich, Germany). The aluminium chloride colorimetric method was used for the determination of the flavonoid content of shade dried herbs with slight modification of Pourmorad et al (2006) using quercetin standard (Sigma Aldrich, Germany).

Calculation of FCR, egg mass, and HDEP

The feed conversion ratio (FCR), hen day egg production (HDEP) and egg mass were calculated by following formulae and expressed as grams of feed consumed per gram of egg produced, percent, and gram per hen per day, respectively.

FCR= [Amount of feed consumed/ (Number of eggs produced × Egg weight)].

HDEP = (Number of eggs laid on a day/Number of birds housed on a day) × 100.

Egg mass= (Egg weight × HDEP)/100.

Determination of egg external quality

Slide calliper was used to measure the egg shape index according to Anderson et al (2004) after taking the nearest value (0.01mm) of egg length and diameter.

Egg shape index, %= (Egg diameter/Egg length) × 100

The egg surface area was measured using the equation cited by Carter (1975), and expressed in cm².

Surface area= 3.9782× (Egg weight) ^0.7056

A digital micro-meter was used to measure the egg shell thickness according to Chowdhury et al (1990). After separation of shell membrane from the egg shell, the weight of shell was taken to calculate the shell percent by adopting following equation.

Shell, % = [Shell weight (g)/ Egg weight (g)] ×100

Determination of egg internal quality

A tripod micro-meter was used for measuring the egg albumen and yolk height, whereas slide calliper was used to measure the albumen and yolk diameter for the determination of albumen and yolk index, respectively. The thick albumen diameter was counted from two side of the albumen and finally average value was considered for the calculation of albumen index by the following formula and expressed as percent. Besides, yolk index was determined using the yolk height and diameter by adopting following formula and expressed in percent. Moreover, Haugh unit (HU) is related to the albumen height and egg weight. The Haugh unit (HU) values were measured according to Monira et al (2003).

Albumen index, %= (Albumen height/Albumen diameter) ×100

Yolk index, % = (Yolk height/Yolk diameter) ×100

Haugh unit= 100Log₁₀ (Albumen height-1.7× Egg weight ^0.37 +7.6)

Roche Yolk color Fan (RYCF) was used for measuring the yolk color from 1 to 15 range adopting by Beardsworth and Hernandez (2004).

Statistical analysis

Raw data on feed intake, egg number, egg production performance and egg external and internal quality assessment were organized using Microsoft Excel program and then subjected to one-way analysis of variance (ANOVA) using IBM SPSS software (Version 23.0, IBM Crop., USA). Data were presented as mean, and the differences at p < 0.05 were considered statistically significant. Duncan multiple range test (DMRT) was conducted to find the difference among the treatment groups.

Results

Egg production performance

As stated in Table 3, greater amount of feed consumption was obtained in herbs powder mixture (HPM) supplemented groups compared to control group at 32-40 weeks. Significantly (P=0.01) better feed intake was measured at HPM15 group compared to other groups and statistically no variation was found between HPM15 and HPM20 groups at 32-40 weeks of age. Supplementation of HPM with basal ration bossed to significant improvement in egg number, egg weight, egg mass and hen day egg production compared to control group. Egg mass was significantly (P=0.000) better in HPM supplemented groups compared to HPM0 group. Better egg mass was calculated at HPM15, then HPM20, followed by HPM5, and HPM10 and no statistical variation were observed among HPM supplemented groups. Incorporation of HPM significantly (P=0.001) increased the hen day egg production compared to control group and better result was calculated at HPM15, then HPM20, followed by HPM5 groups at 32-40 weeks (Figure 1). Feed conversion ratio (FCR) was significantly (P=0.000) better in HPM supplemented groups compared to control group at 32-40 weeks. Better FCR was obtained at HPM15, then HPM10, HPM20, and HPM5 groups, respectively at 32-40 weeks (Figure 2).

Figure 1. Trends of hen day egg production (HDEP) from hen offered different level of herbs powder mixture

Figure 2. Trends of feed conversion ratio (FCR) from hen offered different level of herbs powder mixture

As shown in table 4, addition of herbs powder mixture (HPM) at 5gkg^-1, 10gkg^-1, 15gkg^-1, and 20gkg ^-1 with basal ration had no significant effects on egg shape index, egg surface area, egg shell thickness, shell weight, shell percent, albumen index, yolk index, and Haugh unit. Yolk color significantly ( P=0.001) improved at HPM supplemented groups compared to control group. At end of 40^th week, better yolk color was obtained at HPM15, then HPM10 and followed by HPM20, HPM5, and HPM0 (Figure 3).

Figure 3. Trends of egg yolk color from laying hen offered different level of herbs powder mixture

Discussion

Herbal supplements (Black cumin seed, garlic, marigold, rosemary, lemon oil, oregano oil, thyme, red pepper seed, sage, funnel seed, plantain herb, moringa leaf, african basil, cassava, fluted pumpkin, bitter and ivy-gourd leaf) showed the tendency to improve the production performance of livestock (Al-Mamun et al 2008; Redoy et al 2020) including both broiler (Camy et al 2019) and layer birds (Abou-Elkhair et al 2018; Ather MAM (2000) that is in-line with present study. Addition of lower or higher amount of herbs might be interrupt the optimum performance of the layer birds, as herbs possess phytochemicals (Ebrahim et al 2015). As a result, incorporation of moringa leaves at 0, 1, and 3% in laying hen diet showed highest egg production in 1% group (K. Voemesse et al 2019), whereas better egg production was found in HPM15 group due to level and intensification of phytonutrients from different herbs. Similar to current study, Abou-Elkhair et al (2018) reported that inclusion of 0.5% fennel and hot red pepper seed improved the laying hen performance including egg weight, egg mass, hen day egg production and feed conversion ratio. Ather MAM (2000) reported that inclusion of polyherbal (anise, sage, thyme, fennel seed and oregano) essential oil in broiler breeds merely improved the average egg production that is contrasting to current research. Moreover, polyherbal mixture powder (Plantain, ivy-gourd, garlic and  spearmint) improved the FCR and HDEP that support the previous findings of Deying et al (2005).

Al-Mamun et al (2008) also revealed that plantain herb has potentiality to synthesis whole body protein in animals due to its phytochemicals that might be increased the egg production by enhancing the protein turnover rate in laying hen. Plantain is an excellent source of protein, minerals, polysaccharides, phenolic acids, flavonoids and iridoid glycosides (Al-Mamun et al 2008; Zubair et al 2011) with 77mg α-tocopherol and 149 mg lutein/ kg DM (Anjo Elgersma et al 2013) that’s why increasing the concentration of herbs mixture in ration increased yellow color of egg yolk where HPM offered to the birds. Ivy gourd contents lutein, total xanthophyll and beta carotene at 67.1, 113.0, and 42.1 mg/100g DM, respectively. Hammershøj et al (2010) reported that lutein, xanthophyll and beta carotene increased the yellow color of egg yolk which is in line with current study. Mehran Torki et al (2020) reported that inclusion of essential spearmint oil at 250mg/kg diet did not show any significant difference in feed intake, body weight gain, egg production, egg mass and egg traits in layer bird during 42-56 weeks that is contrasting to present study. Spearspearmint is an excellent source of lutein, zeaxanthin and beta carotene that might be responsible for increasing the yellow color of egg yolk (Aruna Gorusupudi and V. Baskaran 2010). Similar to current study, Asrat et al (2018) found that addition of garlic powder at 1, 2 and 3% in laying hen diet lead to improve the hen day egg production and egg quality. In contrast to this research, inclusion of garlic powder at 2, 4, 5, 6, 8, 10, 20, 60 and 80 gkg^-1 layer diet obtained no significant effect on feed intake, FCR, egg mass and egg traits (Chowdhury et al 2002;Yalcin et al 2006; Khan et al 2008). Asrat et al (2018) found that addition of 2% garlic powder significantly increased the yellow color of egg yolk that is consistent to present study.

Conclusion

• Feeding HMP improved the feed intake, HDEP, egg mass and FCR and egg yolk color.
• HMP with basal ration might be used as a green feed additive in commercial layer industry to improve the laying performance and egg quality.

Acknowledgements

The authors highly acknowledge Bangladesh Agricultural Research Council (NATP-2, PBRG project, SL-099) for the financial support .

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