Efective microorganisms, turmeric (Curcuma longa) as feed additives on production performance and sensory evaluation of eggs from White Leghorn hens

Chala Kinati, Negasi Ameha¹, Meseret Girma¹ and Ajebu Nurfeta²

Department of Animal Sciences, Ambo University, P O Box 19, Ambo, Ethiopia
ck2095@gmail.com
¹ School of Animal and Range Sciences, Haramaya University, P O Box 138, Dire-Dawa, Ethiopia
² School of Animal and Range Sciences, Hawassa University, P O Box 5, Hawassa, Ethiopia

Abstract

This study was conducted to evaluate the effect of commercial effective microorganism (EM), turmeric powder (TP), and their combination as feed additives on layer performance and sensory evaluation of eggs in white leghorn hens. A total of 144 white Leghorn hens, 26 weeks old, were assigned into four treatments, three replications each with twelve-layers per replications. Treatments were control (no additive), 0.5% ml/lit EM, 0.5%TP, and 0.25ml/lit EM and 0.25TP for CTL, EM, TP and EM-TP, respectively. Feed intake, body weight gain, feed conversion ratio, mortality, Egg number/hen, hen-day egg production, and egg mass were similar (P>0.05) among the treatments. Supplementing of laying hen diet with essential microorganisms (EM) and  turmeric powder had no effect on a production but improved egg quality .

Key words: egg quality, laying hens prebitics, probiotic

Introduction

In poultry farming, antibiotics have long been used in low doses to regulate the intestinal microflora of animals. The objective is to prevent certain diseases of the digestive tract and consequently to improve production performance (Dibner and Richards 2005). However, growth-stimulating antibiotics, through the spreading of antibiotic-resistant bacteria, are a threat to human health (Wray and Davies 1997). Following a severe limitation or a general inhibition of using antibiotics as growth stimulating and therapeutic agents in the poultry industry, probiotics and prebiotics have been suggested as appropriate alternatives (Piray et al 2007). Probiotics supplementation into poultry diets improves feed intake and growth performance in poultry (Sarangi et al 2016). Likewise, the inclusion of probiotics significantly improved feed conversion ratio, egg production performance, and egg quality in laying hens (Inatomi 2016).

Effective microorganisms (EM) and turmeric (Curcuma longa ) are some of the probiotic used in layers (KESC 1994).

Laboratory and field trials have shown very good results when using effective microorganisms (EM) on health, performance, disease control, odor control, and waste treatment in poultry production (Wood 2000). Effective microorganism consists of mixed cultures of beneficial and naturally-occurring microorganisms including predominant populations of lactic acid bacteria, yeasts, a small number of photosynthetic bacteria, actinomycetes, and other types of beneficial organisms (EMRO 2003). Fahmy (2009) observed higher average daily weight gain in broilers given 1% of effective microorganism’s solution in the drinking water than the control. Moreover, KESC (1994) reported higher average egg weight, eggshell strength, eggshell thickness, albumen height, Haugh units, and yolk color in EM treated group compared with the nontreated group.

On the other side, phytogenic feed additives are derived from herbs, spices or aromatic plants (Windisch et al 2008) are classes of feed additive that have gained considerable attention in the recent years in the feed industry (Alagawany et al 2016). Turmeric ( Curcuma longa) is one of the phytogenic feed additive and a rhizomatous herbaceous perennial plant of the ginger family, Zingiberaceae. Addition of 0.50 or 1.0% turmeric increased egg weight, egg mass, egg production significantly (Riasi et al 2012). Also, turmeric has been extensively used for giving color and flavor to foods. Laying hens cannot synthesize ingredient for yolk pigments (Karaskova et al 2015), and turmeric could play a significant role in changing the color of yolk in poultry if added to the diet because the composition of laying hen diets affects the pigmentation of egg yolk (Cho et al 2012).

It has been reported that a combination of black cincau leaves and probiotics could increase egg mass of laying hen (Natsir et al 2018). Abdelqader et al (2012) reported that dietary supplementation of probiotic, prebiotic, and combination improved feed conversion and egg performance compared to the control. Another study by Abdel-Wareth (2016) revealed that a combination of thymol and combinations of probiotics and prebiotics (synbiotics) improved productive performances and increased shell percentage, shell thickness, and Haugh unit compared to the control in laying hens. However, there is a lack of information which evaluated the effects of EM, turmeric and their combination on performance and egg quality of laying hens. These two feed additives as a sole or in combination might have different specific activities which include beneficial and synergetic effects on general health status, egg production, and egg quality of laying hens. Therefore, the objective of this study was to evaluate the effect of EM, turmeric, and their combination on layers performance, sensory evaluation of eggs, and economic feasibility in laying hens.

Materials and methods

Description of the study area

The experiment was conducted at Haramaya University poultry farm, which is located 515 km east of the capital, Addis Ababa. The site is situated at an altitude of 1980 meter above sea level, 9ο 26' N latitude, and 42ο 3' E longitude. The mean annual rainfall of the area is 780 mm and the average minimum and maximum temperatures are 8^οC and 24^οC, respectively (Samuel 2008).

Ingredients and treatment rations

Feed ingredients used for the study were maize grain, wheat short, soybean meal, noug seed cake, Turmeric, EM, and salt. Besides, vitamin premix, methionine, limestone, and dicalcium phosphate were added to the ration. (Table 1).

Adequate quantities of activated EM1 packed in a plastic jar was obtained from Weljijie PLC located in Bishoftu, Ethiopia. The EM preparations used in this study were made following the guidelines prepared by EMROSA (2003), hence activated EM1 (0.5-1ml/liter) was added directly into chlorine-free clean drinking water. Turmeric was hammer milled and mixed based on a dry matter basis. The treatment ration used in this study was formulated to be isocaloric (2800-2900 kCal/ME per kg DM) and isonitrogenous (16-17% CP) to meet the nutrient requirements of the layer hen (NRC 1994).

Experimental animals and management

Before the commencement of the actual experiment, watering, feeding troughs, and laying nests and pens were thoroughly cleaned and disinfected. A total of 168 white leghorn chicken breeds at the age of 26 weeks was taken from Haramaya University Poultry Farm and randomly distributed to four experimental rations. In each pen, there were 12 hens and 2 cocks. Birds were fed for 90 days (January - March) with 7 days of adaptation to the experimental diet and house. The birds were kept on deep litter floor housing, which was covered with sawdust litter of about 7cm depth. The house had normal daylighting (12L:12D) across the experimental period. The standard bio-security protocol was employed throughout the experimental period.

Experimental design and treatments

The chickens were assigned to four dietary treatments following a completely randomized design (Table 2).

Data collection and measurements:

Feed intake, body weight change and egg production

Body weight measurements were taken at the start and end of the experiment. The birds were fed ad libitum(⁓20 % refusal) twice a day at 8:00 AM and 4:00 PM. The refusal was collected the next morning and weighed after external contaminants were removed. Feed intake was recorded daily per replicate. Feed conversion efficiency was calculated as gram of egg per gram of feed. Eggs were collected daily and egg production was calculated on a hen-day and hen housed egg production basis following the method of Hunton (1995) as follows:

Average egg weight per replicate was taken as the sum of weights of all eggs collected from each pen divided by the number of eggs collected. Egg mass was calculated by the following formula.

Egg quality parameters

A total of 180 eggs, 36 eggs (3 eggs from each replication) for 4 rounds in every 3^rd week were taken and measured for exterior and interior quality parameters. Eggs were broken, the shell was separated and shell weight was recorded. Shell thickness (without shell membrane) was measured by micrometer gauge. Shell thickness was a mean value of measurements at 3 locations of the eggs (air cell, equator, and sharp end) (Gunlu et al 2003). The average of the three parts was taken as the eggshell thickness. Egg width and length were measured with caliper meter. The egg shape index was calculated as a percentage ratio of egg width to egg length (Anderson et al 2004). The surface area of the egg was calculated using the following relationship by Carter (1970) where S is the surface area in cm² and EW is the egg weight in g.

S = 3.9782 x EW ^0.7056

The length and width of the albumen and yolk were measured in millimeters with the help of a vernier caliper. A tripod micrometer and sensitive balance were used to measure the albumin and yolk height and weight, respectively. Albumen pH was measured by digital pH meter and the albumen index was estimated in percentage, taking the ratio of the respective height to the average of breadth and length. The yolk index was estimated in percentage, taking the ratio of its height to its diameter.

Haugh unit was calculated as HU=100log (AH–1.7 EW^0.37 + 7.6) where

HU=Haugh Unit, AH=Albumen height, and EW=Egg weight according to Haugh (1937). Yolk color was taken from a mixed yolk sample placed on a piece of white paper. The Roche color fan consisting of a series of fifteen colored plastic strips were used as a reference to determine yolk color, with 1 rated as very pale yellow and 15 as deep reddish-orange.

Sensory evaluation of eggs

Sensory analysis was performed by nine panelists who were selected from a postgraduate student and staff members of Animal and Range Science of Haramaya University. They were given preliminary training before the actual testing session and finally asked to evaluate eggs according to Hammershoj and Steenfeldt (2005).

Eggs were collected three days before the tests and stored at 5 ˚C, then presented for panelists after cooking. Four shell eggs per 750 ml of water were heated at 97 ˚C for 15 minutes, transferred to cold water for 10 minutes peeled, divided into halves, kept in 100-ml closed plastic containers for 30 minutes at 20 ˚C, and four eggs were served to each panelist as coded samples. The panelists were asked to evaluate peeled eggs by cutting each egg in half and evaluating color, aroma (odor of the whole egg), flavor (the distinctive aroma and taste of the yolk), presence of any off-flavor (unusual smell or taste of the yolk), and overall acceptability (an integrated sensation based on aroma, flavor, after taste and presence of off-flavor (if any)). Together with the samples, the panelists received a cup of spring water which was kept at room temperature for cleaning their palates. The descriptors were quantified by a 9-point hedonic scale (1 = dislike extremely; 9 = like extremely), except off-flavor property which was described by a 9-point scale (1 = weak; 9 = strong) (Caston et al 1994).

Chemical Analysis

Representative samples were taken from each of the feed ingredients used in the formulation of the ration and milled to pass through a 1 mm sieve screen for chemical analysis. Dry matter (DM), crude proteins (CP), crude fiber (CF), ether extract (EE), and total ash content was analyzed according to A.O.A.C (1990). Nitrogen was determined by using the Kjeldahl procedure and CP was computed by multiplying the N content by 6.25. The metabolizable energy (ME) content was estimated indirectly based on a previously published method (Wiseman 1987):- ME (Kcal/ kg DM) = 3951+ 54.4 EE – 88.7 CF – 40.8 ash

Calcium and phosphorus were determined by atomic absorption spectroscopy and spectrophotometer methods, respectively (AOAC 1998).

Statistical analysis

Data were analyzed using the General Linear Model (GLM) procedure of the Statistical Analysis Systems (SAS 2009). A significant difference among means was determined using the Duncan Multiple Range Test (Duncan 1995). The effect of EM probiotic and Turmeric on layers performance was analyzed using one way ANOVA and the following model was used:

Y_ijk = µ + T_i + E_ij Where, Y_ij = represents the j^th observation in the i^th treatment level,

µ = overall mean of a response variable

T_i = the effect of i^th treatment in the response variable

E_ij = error term

Results and discussion

Chemical composition of the feed ingredients

The CP content of turmeric (8.63%) was lower than the other feed ingredient used in this experiment while ME content was higher in turmeric next to wheat short (Table 3).

Effects of Effective microorganism and Turmeric on productive traits

Feed intake, body weight gain, feed conversion ratio, and mortality was similar among the treatment (Table 4).  Similar to the current result Ahmad et al (2013) indicated that neither the dietary inclusion of prebiotics nor dietary supplementation of probiotics significantly affected body weight gain of the laying hens. On the contrary Inatomi (2016) indicated that probiotics supplementation into poultry diets improved feed intake and growth performance in laying flocks. Moreover, Raka et al (2014) reported a rise in feed and water consumption in laying hens fed with liquid probiotics mixed culture containing two type microorganisms, lactobacillus and bacillus species.

Egg number/hen, hen-day egg production, and egg mass were similar (P>0.05) among treatments. Similarly, Moorthy et al (2009) found no significant effect of feeding 0.1% Curcuma longa on hen house egg production and percent hen day egg production of single comb White Leghorn layers. The egg weight was higher (P<0.05) when a mixture of EM and turmeric were fed together compared with the control (CTL) and EM (EM). This result agreed with Abdel-Wareth (2015), who indicated that the combined effect of thymol and synbiotic on egg weight was higher (p<0.05) compared to the control. Similarly, Park et al (2012) reported that egg productions and egg mass in the groups fed diets with 0.5% TP was significantly higher than the control. This increase could be due to the beneficial EM- microbes in the gut motility region, thereby improving metabolic capacity and contribute to better digestion of feed and enhance animal production performance (Mazanko et al 2017). Turmeric powder can improve the environment in the uterus (specifically the site of calcium deposition) and consequently increase shell weight and thickness (Radwan et al 2008).

Effects of EM and Turmeric inclusion on egg quality parameters

No differences were observed in the shape index, the surface area of egg, shell weight, and shell thickness among treatment (Table ??. Similar egg quality traits were observed in laying hens consuming diets containing Yea-Sacc or Lacto-Sacc (Abdel-Azeem et al 2005). Also, Zeweil (2003) reported that Japanese quail laying hens fed on a diet supplemented with canella did not affect egg quality traits. Moreover, lack of effect of probiotic addition on shell hardness and shell thickness has been reported (Haddadin et al 1996). Similarly, Riasi et al (2008) reported that feeding different levels (0, 0.5, 1.0, 1.5, and 2.0 g/kg of feed) of turmeric to the laying hens had no effect on specific gravity, eggshell thickness, eggshell weight, and eggs shell weight to egg weight ratio.

Albumen height, albumen length, albumen width, albumen pH, albumen index, yolk weight, yolk width, yolk height, and yolk index) were similar (Table 5) among treatments. The egg yolk color score was higher (p<0.05) in laying hens fed a combination of turmeric and EM and turmeric alone compared with EM alone and where no additive was used. The results of the present study suggest that egg yolk color was influenced by the consumption of turmeric (Curcuma longa) from the yellowish pigment of turmeric (curcuminoids, curcumin, and its related compounds) (Riasi et al 2012). Also, Park et al (2012) observed improvement in yolk color by the addition of 0.5% dietary turmeric powder to the diet of laying hens. Likewise, Gumus et al (2018) indicated that addition of 0.5% turmeric powder increased yolk color by 17% compared with the control diet. On the contrary, Radwan et al (2008) reported that addition of turmeric to hen ration did not affect the yolk color and Haugh unit, but it significantly improved the yolk index.

Albumen weight in the current experiment was higher (p<0.05) in laying hens fed a combination of 0.25% turmeric and 0.25 ml/lit EM than the control. Likewise, Simeamelak et al (2013) indicated that Haugh unit, yolk color, and albumen weight of eggs from control treatment were lower than the eggs from those fed 4, 8, and 12 ml of EM. The lowest (P<0.05) Haugh in the current experiment was for the control group. A combination of EM and turmeric has improved the yolk color compared with the control and EM alone in the current study. However, no reference was available with regard to feeding a combination of EM and turmeric on layers egg quality.

Sensory evaluation

Mean values in egg white and egg yolk color, aroma, flavor, off-flavor, and overall acceptance were similar (Table 6.) Among treatments except for yolk color where those group fed 0.50% TP and 0.25 ml/lit EM + 0.25% TP was more (P<0.05) preferred by the panelist than that of control and EM group. Jacqueline et al (1998) reported that yolk color depends on the diet of the hen, and if layers get plenty of yellow-orange plant pigments known as a xanthophyll, they will be deposited in the yolk. Natural yellow-orange substances in turmeric might be added to light-colored feeds to enhance yolk color (Park et al 2012).

Conclusions

• Supplementing of laying hen diet with essential microorganisms (EM) and  turmeric powder had no effect on a production but improved egg quality.

Acknowledgments

The authors would like to thank the Ethiopian Ministry of Education, Ambo University, and HaramayaUniversity Research Affairs Office for facilitating the working area to implement the research project. Special appreciation is to Haramaya University poultry farm and Animal nutrition laboratory workers for their kind support.

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