Effects of Saccharomyces Cerevisiae Supplemented Diet on Production Performance, Egg Quality and Humoral Immunity in Black Australorp and Fayoumi Layers

ABSTRACT

The present study intended to identify the effects of the Saccharomyces cerevisiae yeast on production performance and parameters related to the quality of layers’ eggs. Effects of yeast on immune titers after routine vaccinations against Newcastle disease and infectious bronchitis were also studied. Fayoumi chicken (n=288) were divided in four groups (72 in each), and Black Australorp (n=288) in four groups (72 in each). Both had 12 weeks of age and were kept in 08 groups (3 replicates per treatment). Hens were fed a controlled diet along with the addition of 0.5g, 1.0 g, and 1.5 g of S. cerevisiae per kg of feed, till 25 weeks of age. Feed intake and egg production were measured on a daily basis, while body weight gain and egg weight were measured weekly. Egg quality parameters were evaluated by picking 5 eggs from every group weekly. Birds were vaccinated for Newcastle disease (ND) and infectious bronchitis (IB) at the 18^th week. Subsequently, 10 days after vaccination, antibody titers were determined by Hemagglutination Inhibition and Enzyme Linked Immunosorbent Assay for both diseases. Results showed no significant effect of S. cerevisiae on layers’ weight gain and feed intake. However, egg production was increased in the experimental group. Moreover, yeast supplementation impacted positively on birds’ immune system. In conclusion, probiotic supplementation improved birds’ egg production and immunity.

Keywords:
Egg production; Egg Quality; Immunity; Probiotic; Saccharomyces cerevisiae

INTRODUCTION

Poultry meat and eggs are important protein sources for humans. According to Leeson (2012), there has been an increase in demand for food products, causing a qualitative and quantitative increase in production in the poultry industry. The use of probiotics and prebiotics in the poultry industry is encouraged due to the rising issue of antimicrobial resistance (AMR) and antibiotic residues’ incorporation in poultry products Patterson & Burkholder (2003). According to WHO/FAO (2001), probiotics are micro‐organisms that live in nature and confer benefits to the host, when given in ample amounts. Probiotics comprise live microbe cultures, such as yeast, fungi, and bacteria that positively affect the health and nutrition status of animals by developing their intestinal microbes Khan et al. (2011); Zhang & Kim (2014). The most widely used type of yeast, Saccharomyces cerevisiae, has been reported to improve feed quality and the performance of animals Martin et al. (1989). Major effects of using probiotics include growth improvement, reduction in mortality, Kumprecht & Zobac (1998) and better feed conversion efficiency Yeo & Kim (1997). Supplementing with Pediococcus acidilactici showed improvement in the weight of eggs and quality of eggshells along with reducing the percentage of broken eggs in layers Mikulski et al. (2012). Supplementing layer diets with probiotics has shown evidences of reducing the concentration of cholesterol in egg yolk Abdulrahim et al. (1996) and serum in chicken Jin et al. (1998). Multi-strain probiotics have been reported to lower feed conversion ratios and numbers of damaged eggs Balevi et al. (2001). Immuno-modulation is also one of the benefits published in literature Salianeh et al. (2011). Nayebpor et al. (2007) and Apata (2008) reported the positive immune-modulatory effects of using probiotics. Supplementation of probiotics in the diet may have substantial effects in different species of animals and even among different breeds within species Fasina & Thanissery (2011); Fathi et al. (2012). Therefore, the current study was designed to investigate the effects of supplementing a S. cerevisiae probiotic on egg production, egg quality, and immune response on Fayoumi and Black Australorp layers.

MATERIALS AND METHODS

The study was carried out at the poultry farms of the Directorate of Poultry Research Institute, Rawalpindi, Pakistan. Egg analysis was carried out at the Feed and Water Testing Laboratory - Poultry Research Institute, Rawalpindi, Pakistan using an Automatic Egg Quality Analyzer. Afterwards, IB and ND antibody titers were assayed at the Disease and Diagnostic Laboratory, Poultry Research Institute, Rawalpindi.

Pullets

The experiment was carried out by allocating 576 pullets, 12 weeks old (Fayoumi and Black Australorp) into four groups of each strain, i.e., 288 Black Fyuomi (n=72 each) and 288 of Australorp (n=72 each). The details of group names and inclusion levels of the probiotic are given in Table 1. The experiment lasted up to 25 weeks.

Table 1
Inclusion Level of Probiotic.

Sr. No.	Group Name	Description	Inclusion Rate
1	A1F	Probiotic (Fayoumi)	0.5 g / kg of feed
2	A2F	Probiotic (Fayoumi)	1.0 g / kg of feed
3	A3F	Probiotic (Fayoumi)	1.5 g / kg of feed
4	CF	CONTROL Fayoumi	No probiotic
5	A1B	Probiotic (Black Australorp)	0.5 g / kg of feed
6	A2B	Probiotic (Black Australorp)	1.0 g / kg of feed
7	A3B	Probiotic (Black Australorp)	1.5 g / kg of feed
8	CB	CONTROL Black Australorp	No probiotic

Bird Management

All groups were kept on floor in separate pens equipped with round feeders and automatic drinker sand. A controlled diet in crumbs form was provided during the whole experimental phase to meet the nutritional requirements of layer birds. This basal diet was supplemented by incorporating probiotic preparations in different concentrations. Ventilation, ambient temperature, humidity, lighting, litter, and other environment conditions met the management requirements of layers. No cross-contamination among groups was permitted. Birds were vaccinated against IB and ND at the 18^th week of age.

Probiotic

Commercial probiotic (Actera Yeast) ^® containing S. cerevisiae with live yeast cell count ≥ 20 billion/g was supplemented in feed at the 0.5 gm, 1.0 gm, and 1.5 gm/kg levels, and was given throughout the study time i.e., up to 25 weeks. The composition of the probiotic is shown in Table 2.

Table 2
Probiotic Composition.

Ingredient	Composition
Live Yeast Cell Count (Billion/g)	≥ 20
Protein %	≥ 46
Ash	≤ 7
Arsenic	≤ 2ppm
Lead (Pb)	≤ 10ppm
Vitamin B Complex	Positive
Salmonella	Negative

Performance Evaluation

Performance was evaluated by measuring the intake of feed and the amount of eggs produced on a daily basis. Weight gain and egg quality parameters (external and internal) were assessed weekly. Feed Conversion efficiency (FCE) was also calculated for each treatment. FCE was calculated as grams of consumed feed per gram of egg produced.

Egg Quality Evaluation

Egg production was measured daily. Afterwards, samples of eggs were weighed and egg parameters were assessed on a weekly basis. 5 eggs from each group were collected every week to assess egg quality. Parameters were egg weight, yolk weight ratio, yolk color, albumen weight, albumin ratio, albumin height, egg shape index, egg shell weight, egg shell ratio, shell thickness, and Haugh unit. Eggs were first weighed and then broken on a plane surface/egg analyzer plate and the height of the albumen was measured by using an albumen height gauge. Eggs were analyzed by an automatic egg analyzer machine and egg weight, Haugh unit, albumin weight, and yolk weight were measured. Before evaluating the yolk weight, each egg yolk was rolled on blotting paper in order to remove the remaining albumen. Subsequently, egg albumin percentage and egg yolk percentage were calculated. Yolk color was measured by Roche’s egg yolk color fan. The egg shells were left to dry out at room temperature and then weighed. Shell thickness was measured by a micrometer from top, equator, and truncated edge of egg and was averaged and recorded as shell thickness. Afterwards, the shell was left to dry at room temperature and weight was also calculated as a percentage. The maximum length and width of each egg was measured with calipers, and their shape index was determined by the formula:

$Shapeindex=\left[\max imumwidthinmm/\max imumlengthinmm\right]x100$

Antibody Titer against ND virus

The Hemagglutination Inhibition (HI) test was used to determine Antibody titer against Newcastle disease virus Thayer & Beard (1998). The procedure was performed at the Disease Diagnostic Laboratory, Poultry Research Institute, Rawalpindi, Pakistan. Blood samples from 5 birds of each group were collected on the 10^th day post vaccination. Separated serum was processed for the HI test.

Antibody titer against IB virus

From each group, 5 blood samples were collected 10 days after vaccination and serum was further processed. The presence of IBV antibodies were assayed using an ELISA kit (IDEXX® Laboratories Inc. United States) at Disease and Diagnostic Lab, Poultry Research Institute, Rawalpindi, by following the manufacturer’s instructions.

Statistical Analysis

The data was analyzed against each parameter using one way ANOVA that compared each parameter in 3 groups with control for both Black Australorp and Fayoumi, separately. Significant parameters were represented with a “*” in superscript of its p-value and non-significant with “ns”. The number of “*” represents the level of significance of the parameter. Moreover, significant parameters were further compared in group pairs using Tukey’s Multiple Comparison Test (TMCT). The whole statistical analysis was performed on Graph pad Prism version 6.01.

RESULTS

Production Performance (Black Australorp)

Out of the several analyzed production performance parameters, only egg weight was found significant for Black Australorp birds. Regarding egg weight, all the three treatment groups of black Australorp showed significant increase compared to the control group (Fig. 1, Table 3). This means that Saccharomyces cerevisiae supplementation has a positive impact on egg weight gain. Mortality of layers in the control groups was not significantly different from layers in the experimental groups. Increasing the dose of probiotic supplement did not cause any considerable effect on mortality. Our results were in contrast with Netherwood et al. (1999), who reported there was an increase in survival rate (decrease in % mortality) by supplementing probiotics, due to modification in gut microflora. Likewise, another study by Ehrmann et al. (2002) showed suppression in growth rate of pathogenic bacteria by using probiotics. Body weights were measured weekly. Effect of Saccharomyces cerevisiae on production parameters through one way ANOVA and TMCT are given in Table 3.

Table 3
Effect of Saccharomyces cerevisiae on production parameters.

One way ANOVA
	For Group Fayoumi		For Group Black Australorp
Factors	Mean ± SD	p-value	Mean ± SD	p-value
Weight Gain (kg)	1.243 ± 0.096	0.5582ns	1.479 ± 0.141	0.9882ns
Avg. Feed Intake /day (g)	100.75 ± 3.594	0.9596ns	102 ± 3.109	0.3495ns
Avg. Egg Production /day	8.675 ± 0.629	0.0874ns	9.875 ± 0.818	0.3495ns
Egg weight (g)	43.35 ± 1.556	0.0872ns	41.603 ± 1.432	0.0002***
Mortality (%)	0.05 ± 0.1	0.0519 ns	0.05 ± 0.1	0.0519 ns
FCE	2.3175 ± 0.238	0.7015ns	2.45 ± 0.056	0.2419ns
TMCT
	For Group Fayoumi		For Group Black Australorp
Factors	Comparative groups	Level of significance	Comparative groups	Level of significance
Egg weight (g)	-	-	Control vs A1B	**
	-	-	Control vs A2B	***
	-	-	Control vs A3B	***

Figure 1
Significant production parameter is shown for Black Australorp birds.

There was no significant difference in the body weights and feed intake within treatment groups fed different levels of probiotic, as shown in graph 1 and 2. The average feed intake (98g/day) was lowest in group A3B (Black australorp) 1.5 g probiotic/ kg feed, when judged against the control group (104 g/day). Maximum egg production was observed in the Black Australorp group fed with 0.5 g probiotic/ kg of feed. Egg production was recorded as 66%, while the control groups had an average egg production of 53.3%.

Egg Quality (Black Australorp)

The traits of eggs during 20-25 weeks of age including egg weight, Haugh unit, albumin and yolk weight, albumin percentage, egg yolk percentage, albumin height, egg shape index, egg shell weight, and shell thickness were measured. The effect of Saccharomyces cerevisiae on egg quality parameters determined through one way ANOVA and TMCT are summarized in Table 4. Significant improvement in egg quality for each treatment was found in yolk weight, yolk ratio, egg shell ratio, albumin weight, egg shell weight, and Haugh unit (shown in Fig. 2).

Table 4
Effect of Saccharomyces cerevisiae on egg quality parameters.

One way ANOVA
	For Group Fayoumi		For Group Black Australorp
Factors	Mean ± SD	p-value	Mean ± SD	p-value
Egg Weight(g)	42.258 ± 0.518	0.4830ns	42.685 ± 2.231	<0.0001****
Yolk Weight (g)	12.913 ± 0.369	0.8346ns	12.625 ± 1.001	<0.0001****
Yolk Ratio%	30.563 ± 0.824	0.1323ns	29.566 ± 1.053	<0.0001****
Yolk Color	8.32 ± 0.5	0.8652ns	8.800 ± 0.5	0.5523ns
Albumin weight (g)	29.104 ± 0.524	0.4065ns	30.043 ± 1.33	<0.0001****
Albumin Ratio %	69.188 ± 0.824	0.4122ns	70.453 ± 1.053	0.1410ns
Egg White Height (mm)	5.420 ± 0.05	0.8142ns	5.394 ± 0.052	0.9906ns
Egg Shape index	1.133 ± 0.041	0.9666ns	1.183 ± 0.056	0.6407ns
Egg Shell Weight(g)	5.727 ± 0.229	0.9979ns	5.728 ± 0.301	<0.0001****
Egg Shell Ratio %	13.583 ± 0.012	0.9738ns	13.583 ± 6.094	<0.0001****
Shell Thickness (mm)	0.308 ± 0.0465	0.9757ns	0.308 ± 0.565	0.7454ns
Haugh unit	65.485 ± 3.041	<0.0001****	65.485 ± 3.175	<0.0001****
TMCT
	For Group Fayoumi		For Group Black Australorp
Factors	Comparative groups	Level of significance	Comparative groups	Level of significance
Egg Weight(g)	-	-	Control vs A1B	****
	-	-	Control vs A2B	****
	-	-	Control vs A3B	****
	-	-	A1B vs A2B	****
	-	-	A1B vs A3B	****
	-	-	A2B vs A3B	****
Yolk Weight (g)	-	-	Control vs A1B	****
	-	-	Control vs A2B	****
	-	-	Control vs A3B	****
	-	-	A1B vs A2B	****
	-	-	A1B vs A3B	****
Yolk Ratio%	-	-	Control vs A2B	****
	-	-	Control vs A3B	****
	-	-	A1B vs A2B	****
	-	-	A1B vs A3B	****
	-	-	A2B vs A3B	**
Albumin weight (g)	-	-	Control vs A2B	****
	-	-	Control vs A3B	****
	-	-	A1B vs A2B	*
	-	-	A1B vs A3B	****
	-	-	A2B vs A3B	****
Egg Shell Weight(g)	-	-	Control vs A1B	***
	-	-	Control vs A2B	**
	-	-	Control vs A3B	****
	-	-	A1B vs A3B	*
	-	-	A2B vs A3B	**
Egg Shell Ratio %	-	-	Control vs A2B	****
	-	-	Control vs A3B	****
	-	-	A1B vs A2B	****
	-	-	A1B vs A3B	****
	-	-	A2B vs A3B	****
Haugh unit	Control vs A1F	****	Control vs A1B	****
	Control vs A2F	****	Control vs A2B	****
	Control vs A3F	***	Control vs A3B	****
	A1B vs A3B	**	A1B vs A2B	****
	A2B vs A3B	***	A1B vs A3B	****
			A2B vs A3B	****

Figure 2
Significant egg quality parameters are shown for Black Australorp birds.

Production Performance (Fayoumi)

No significant change was found in any parameter of production performance (Table 3).

Egg Quality (Fayoumi)

Only Haugh unit showed significant improvement in all treatment groups compared to the control group (Fig. 3).

Figure 3
Significant egg quality parameter is shown for Fayoumi birds.

Immune Responses

The geometric mean titers (GMT) obtained after the HI assay of treated birds was higher than that of the control group (Table 5). Probiotic inclusion in diet resulted in an increased antibody titer against ND as compared to the control. Similarly, titers obtained in response to ELISA performed for IB was also significantly higher in treatment groups (Table 5).

Table 5
Effect of Saccharomyces cerevisiae on antibody titers against New Castle Disease and Infectious Bronchitis Disease.

ELISA (IBV Titer)	Parameters			0	Groups
		A1B	A2B	A3B	CB	A1F	A2F	A3F	CF
	O. D	0.523	0.449	0.637	0.189	0.449	0.491	0.637	0.086
	Mean	0.523	0.449	0.637	0.189	0.449	0.491	0.637	0.086
	S/P	5.16	3.48	4.14	1.25	3.49	3.86	5.17	0.24
	Titer	13717	8938	10799	2922	8938	9990	8999	484
	Log2	14	13	13	12	13	13	13	9
	Result	Pos	Pos	Pos	Pos	Pos	Pos	Pos	Pos
H.I (ND Titer)	H.I Test reading (GMT log-2)	10	8	9	7	9	9	9	8

DISCUSSION

No considerable effects on body weight gain have been reported by using probiotics for layers Yalçın et al. (2012); Hassanein & Soliman (2010). Likewise, no significant body weight gain was obvious during this study. In contrast, Shareef & Al-Dabbagh (2009); Fasina & Thanissery (2011); Fathi et al. (2012) have shown positive weight gain due to the supplementation of probiotics in broilers, which may involve certain other factors including difference in strains and species of animals used.

Maximum weight of egg (p<0.05) was seen in Black Australorp hens which were given 0.5 gm of 44.5 gm during the experiment. Our findings were consistent with other studies Ayanvale et al. (2006); Yalçin et al. (2008); Yalçın et al. (2015); Zhong et al. (2016), but differed from Nursoy et al. (2004); Asli et al. (2007); Hassanein & Soliman (2010); Gül et al. (2013); Sacakli et al. (2013).

Shape index, albumin & yolk weight, and shell weight were not statistically different. The results were consistent with the studies of Asli et al. (2007); Hassanein & Soliman (2010); Yalçın et al. (2012); Yalçın et al. (2014); Yalçın et al. (2015). The highest yolk weight and percentage was found in the group A3B fed 1.5 gm of yeast. The lowest albumen percentage was also observed in the same group. The maximum Haugh Unit (HU) was found in the Fayoumi breed supplemented with 1.0 mg of probiotic per kg. Similarly, earlier studies Ayanwale et al. (2006); Yousefi & Karkoodi (2007); Asli et al. (2007); Zhong et al. (2016) reported positive effects on birds by supplementing yeast.

The current study revealed that resistance against diseases improved in hens, but no significant effect on body weight was observed due to probiotic supplementation. ND and IB titers were high in all treatment groups when compared to control, which may be explained by an increase in availability of serum immunoglobulin. Systemic antibodies in response to various antigens may get modulated due to Probiotics Huang et al. (2004). In another study, a significant increase in serum antibodies was found in response to sheep red blood cells (SRBC) by Haghighi et al. (2006) when compared to control ones. Kabir et al. (2004) assessed the activity of probiotics on broiler’s immune response and reported a considerably high antibody response in trial birds as compared to the controls. Cheng et al. (2004) suggested that probiotic feeding enhanced some cell mediated immune responses in broilers by modifying macrophage activity. Our results were consistent with Shoeib et al. (1997), who found an increase in the number of follicles in the Bursa of Fabricious in a probiotic treated group, ultimately resulting in high medullar plasma cell reaction.

CONCLUSION

Experimental findings concluded that Saccharomyces cerevisiae supplementation has minimal effect on weight gain and feed intake, but has more pronounced effects on egg production in Black Austarlorp and Fayoumi layers. Egg Quality parameters were not affected by Saccharomyces cerevisiae inclusion in feed.

ACKNOWLEDGEMENTS

The kind supervision and valuable comments of Dr. Abdul Rehman, Director Poultry Research Institute, Rawalpindi, Pakistan during the trial is highly acknowledged.

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Publication Dates

• Publication in this collection
  07 Apr 2023
• Date of issue
  2023

History

• Received
  13 Dec 2021
• Accepted
  28 Sept 2022