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Article

Effects of Citric Acid, Synbiotic, and Probiotic Supplementation Through Drinking Water on Growth Performance, Carcass Yield, and Blood Biochemistry of Broiler Chickens

by
Shahadot Hossain
1,
Biswajit Kumar Biswas
2,
Subir Das
2,
Faija Sadia Pory
2,
Rabin Raut
3,
Fatima Yeasmin
4,
Sharif Uddin Khan
5,
Prantho Malakar Dipta
6,
Sabbir Alom Shuvo
7,
Tahera Yeasmin
1 and
Raihanul Hoque
2,*
1
Department of Dairy and Poultry Science, Hajee Mohammad Danesh Science and Technology University, Dinajpur 5200, Bangladesh
2
Department of Food and Animal Sciences, Tennessee State University, Nashville, TN 37209, USA
3
Department of Poultry Science, Auburn University, Auburn, AL 36849, USA
4
College of Engineering & Science, Molecular Science and Nanotechnology, Louisiana Tech University, Ruston, LA 71272, USA
5
Department of Animal Science, Animal Molecular & Cellular Biology, University of Florida, Gainesville, FL 32611, USA
6
Department of Poultry Science, Center of Excellence for Poultry Science, University of Arkansas, Fayetteville, AR 72701, USA
7
College of Engineering & Science, Computational Analysis and Modeling, Louisiana Tech University, Ruston, LA 71272, USA
*
Author to whom correspondence should be addressed.
Animals 2025, 15(8), 1168; https://doi.org/10.3390/ani15081168
Submission received: 25 March 2025 / Revised: 11 April 2025 / Accepted: 15 April 2025 / Published: 18 April 2025
(This article belongs to the Special Issue Poultry Nutrition and Management)
Review Reports Versions Notes

Simple Summary

Poultry farming is experiencing rapid growth in Bangladesh, where the use of antibiotics as growth promoters is still common. However, with rising concerns about antibiotic resistance and changing market demands, there is an urgent need to identify effective non-antibiotic alternatives, especially for small- and medium-scale poultry farmers. This study was designed to investigate the effects of citric acid, synbiotics, and probiotics supplemented through drinking water on the growth, carcass yield, and blood metabolites of broiler chickens. The probiotic group achieved higher body weight, weight gain, and better feed efficiency compared to the other groups. Additionally, probiotics showed the best results regarding beneficial changes in blood parameters, including cholesterol and low-density lipoprotein levels. In conclusion, while citric acid and synbiotics also provide noticeable improvements, probiotics are the most effective alternative for enhancing broiler growth and overall performance in poultry farming.

Abstract

A study was undertaken to investigate the effects of non-antibiotic additives—citric acid, synbiotics, and probiotics—administered through drinking water on broiler growth performance, carcass characteristics, and blood biochemical profiles. A total of 400 one-day-old Cobb 500 broiler chicks were randomly divided into four treatment groups: Control; no additives administered (CON); Citric acid @2.5 g/L water (CA); Synbiotic @0.2 g/L water (SB); Probiotic @0.5 g/L water (PB) and with each group having 4 replicates of 25 chicks. Growth performance metrics, such as body weight (BW), body weight gain (BWG), feed intake (FI), and feed conversion ratio (FCR), were recorded weekly. At the end of the trial, the probiotic-fed group had significantly higher BW (p = 0.018), BWG (p = 0.027), and an improved FCR (1.62) compared to the CON (1.74), CA (1.66), and SB (1.70) groups (p = 0.042). Biochemical parameters showed significant differences in total cholesterol (p = 0.013) and low-density lipoprotein (LDL) levels (p = 0.039), with the PB group showing higher levels. These results suggest that citric acid, synbiotics, and probiotic additives provided through drinking water can enhance broiler growth performance, with probiotics offering the most promising benefits.

1. Introduction

The poultry sector in Bangladesh is rapidly shifting from traditional backyard farming to commercial production systems, with an annual increase of approximately 15% in commercial poultry farms to meet the protein demands of the growing population [1]. In Bangladesh, most commercial poultry farms use antimicrobials during production and for prophylactic purposes [2]. However, rising consumer demand for antibiotic-free meat and concerns over antimicrobial resistance (AMR) from regulatory bodies have led to stricter policies. In 2010, the Bangladesh government passed the “Bangladesh Fish Feed and Animal Feed Act 2010”, prohibiting the inclusion of antibiotics, growth hormones, steroids, and insecticides in animal feed during manufacturing [3]. While antimicrobial restrictions aim to mitigate AMR, they also present significant challenges if not properly addressed. Seasonal variations and ignorance of other factors such as biosecurity, litter management, water sanitation, and stocking density create favorable conditions for microbial growth, compromising bird health [4,5]. Therefore, identifying cost-effective alternatives that maintain broiler health while promoting faster growth is essential, especially considering the cost management constraints in poultry production.
Several non-antibiotic growth promoters, such as phytogenic feed additives, probiotics, prebiotics, synbiotics, and citric acids, have been explored for their efficacy in promoting growth and maintaining health without compromising food safety [3,6,7]. Citric acid improves nutrient digestion, regulates intestinal pH, and reduces harmful bacteria like E. coli [8,9] while promoting beneficial organisms like Lactobacillus, Bifidobacterium, and Enterococcus species. Probiotics balance gut microbiota, enhance digestion, and strengthen immunity [10]. Synbiotics, combining probiotics and prebiotics, improve feed efficiency, boost immunity, and increase disease resistance [11]. These additives collectively enhance gut health, growth performance, and sustainability in poultry farming. Small- to mid-scale farmers in Bangladesh are faced with poverty [12] and illiteracy, which limits their access to proper equipment for efficiently mixing feed additives. As a result, adding these additives to the water rather than the feed could provide a more practical and effective solution [13] for farmers in developing countries like Bangladesh. Based on previous studies on poultry with varying doses of these additives, we hypothesized that the inclusion of citric acids, synbiotics, and probiotics in drinking water could improve broiler performance while positively influencing blood profile parameters. The objective of this study was to evaluate the impact of citric acids, synbiotics, and probiotics on growth performance, meat yield, dressing parameters, and the blood profile of Cobb-500 broiler chickens.

2. Materials and Methods

This experiment was conducted at the experimental poultry farm of Hajee Mohammad Danesh Science and Technology University (HSTU), Dinajpur, Bangladesh. All the experimental procedures involving animals were revised and approved by the Animal Ethics Committee of Hajee Mohammad Danesh Science and Technology University.

2.1. Additives Procurement and Composition

Citric acid was purchased from Merck Specialties Private Limited, (Warli, Mumbai, India). Synbiotics were sourced from K.M.P. Biotech Co., Ltd., (Chonburi, Thailand) with each gram containing Bacillus subtilis (≥5 × 109 CFU/g), Pediococcus acidilacticii (≥5 × 109 CFU/g), Enterococcus faecium (≥5 × 109 CFU/g), Saccharomyces cerevisiae (≥1 × 109 CFU/g), and Xylo-oligosaccharide (35 g). Probiotics were obtained from Sanzyme Biologics (P) Ltd. (Hyderabad, India), with each gram containing Bacillus subtilis (≥4.5 × 109 CFU/g), Bacillus coagulans (≥4.5 × 109 CFU/g), and Saccharomyces boulardii (≥4.5 × 109 CFU/g).

2.2. Experimental Design and Diet

A total of 400 one-day-old Cobb 500 broiler chickens (48.04 ± 1.36) g were randomly assigned to one of 4 treatment groups, with 4 replicates per treatment (25 birds per pen). The study included 3 additive treatments—Citric acid (CA) (2.5 g/L), Symbiotic (SB) (0.2 g/L), and Probiotic (PB) (0.5 g/L)—along with a control (CON) group that received no additives, and each was administered through drinking water for 35 days. Drinking water was changed in every 6 h interval from the 6 a.m. to 12 p.m. period of the day. The birds were raised in a semi-controlled shed where shed temperature and humidity were checked and measured four times a day (8 a.m., 12 p.m., 4 p.m., and 8 p.m.) using an automated thermo-hygrometer. Each pen measured 30 square feet (10 feet × 3 feet). The experimental shed and required related equipment were cleaned and disinfected using a 1% TH4+ solution (0.1-L diluted solution per square foot) and a 0.5% TH4+ solution, respectively (Manufactured by Sogeval, France, and distributed by Century Agro Ltd., Dhaka, Bangladesh). Fresh rice husk was used as the litter material and litter depth was maintained at 5–6 cm. Ad libitum feed and water were provided throughout the experiment. A commercial-type broiler diet (Table 1) divided into two different phases containing the starter phase d (0–14), and the grower d (15–35) was used as the experimental diet.

2.3. Performance and Carcass Characteristics

The body weight of the broilers was determined on d 0, 7, 14, 21, and 35, and feed intake (FI) was assessed daily by accounting for the feed offered and the leftovers. The body weight gain (BWG) and feed conversion ratio (FCR) were calculated using recorded data at each wk. To assess dressing yield, 80 randomly selected birds (5 birds per replication) were sacrificed by the cervical dislocation method on d 35. The live weight, dressed weight, thigh weight, breast meat weight, drumstick weight, and wing meat weight of slaughtered birds were collected and weighed just after sacrifice by a trained professional. The organ index was calculated using the formula: organ weight/live body weight × 100.

2.4. Blood Biochemistry

Approximately 3–4 mL of blood was collected from each replicate bird into sterile glass test tubes. The tubes were positioned at a 45° angle at room temperature to allow for clotting. After 2 h, the separated serum was carefully transferred into Eppendorf tubes and centrifuged at 3000 rpm for 10 min. The supernatant serum was then transferred to new Eppendorf tubes, properly labeled with a permanent marker for easy identification during chemical analysis and stored at −20 °C until further analysis. The serum lipid profile, including cholesterol, triglycerides, high-density lipoprotein (HDL), and low-density lipoprotein (LDL), was determined following standard procedures. Briefly, total cholesterol and triglycerides were determined using spectrophotometry (Spectronic, Genesis 5, Melville, NY, USA) following the methods described by [14]. HDL was analyzed by incubating 200 μL of serum with 500 μL of reagent at room temperature for 10 min before measuring absorbance at 505 nm. The concentrations (expressed in mg/dL) of cholesterol, triglycerides, HDL, and LDL were calculated using the following formulas.
Cholesterol (mg/dL) = (Absorbance of sample/Absorbance of standard) × 200
Triglycerides (mg/dL) = (Absorbance of sample/Absorbance of Standard) × Concentration of standard
HDL (mg/dL) = (A505nm) × 320; A 505 nm (Sample read) is the absorbance value of the sample measured at 505 nm wavelength.
LDL (mg/dL) = (Total serum cholesterol-Triglyceride/5) × HDL

2.5. Statistical Analysis

Data were analyzed using the analysis of variance techniques to determine significant differences between the means of different treatment groups in SAS 9.4 software (SAS Institute Inc., Cary, NC, USA, 2000), following the principles of a completely randomized design. To determine significant differences among treatments, the Duncan Multiple Range Test was performed. Statistical significance was set at p < 0.05, while trends were between 0.05 to 0.1.

3. Results

3.1. Broiler Performance

The effects of citric acid, synbiotic, and probiotic-treated drinking water on broiler growth performance, FI, and FCR are summarized in Table 2. Feed intake showed significant variation (p < 0.05) in the 5th week and overall, with the CON group consuming the highest amount of feed (2984.18 g), followed by the CA, SB, and PB groups. Significant differences (p < 0.05) were observed in BW and BWG from the 4th week onward. In the 4th week, the probiotic group demonstrated the highest BW (1533.52 g) and BWG (463.84 g) compared to the CON group (1482.76 g and 258.41 g, respectively). In the 5th week, the CA group exhibited a higher BWG (274.59 g) than the CON group (258.41 g). By the end of the trial, the PB group achieved the highest final BW (1746.66 g) and BWG among all dietary groups. FCR also differed significantly (p < 0.05), with the PB group showing the best FCR (1.62) compared to the CON group (1.74) during the 4th and 5th weeks, and the entire experimental period. No significant differences in FCR were observed between the CA (1.66) and SB (1.65) groups compared to the CON group.

3.2. Carcass Yield

Table 3 reveals that there were no significant differences in meat yield and bone development across the dietary treatment groups. However, the CA, SB, and PB groups showed numerically higher dressing percentages than the CON group. According to Table 4, there were no significant differences in head, neck, heart, and leg weight relative to body weight among the dietary groups.

3.3. Blood Biochemistry

In Table 4, the CON group had significantly the highest cholesterol and LDL levels (p < 0.05) compared to the other treated groups. No significant differences were observed in triglycerides and HDL levels among the treatment groups. All the supplemented groups displayed lower total cholesterol (p = 0.013) and LDL (p = 0.039) levels compared to the CON group.

4. Discussion

The results from the present study demonstrate that broilers supplemented with probiotic, synbiotic, and citric acid additives exhibited significant improvements in growth performance, FI, and FCR compared to the CON group. Probiotic supplementation showed the most consistent positive effects on BW and BWG, particularly from the 4th week onwards, aligning with studies that have highlighted probiotics role in improving feed utilization and enhancing growth through the modulation of gut microbiota [15]. This is supported by the findings of Rehman et al. and Biswas et al. [16,17], where probiotics supplemented through diet-enhanced BW and feed conversion efficiency in broilers by promoting more efficient nutrient absorption and better digestive health. In the present study, we observed a decrease in feed intake in treatment groups compared to the control. However, this finding aligns with the concept that feed intake is not always directly correlated with growth performance [18]. Several studies have mentioned increased feed intake with probiotic supplementation [19], while others have observed no effect [20], making efficiency of feed utilization the key factor. Probiotics may enhance the birds’ ability to digest and absorb nutrients, leading to better nutrient utilization [21,22] and reduced feed consumption.
The higher growth rates in the synbiotic-supplemented group are consistent with [23], who have shown that the synergistic effects of prebiotics and probiotics in synbiotics improve gut health and nutrient absorption, leading to better growth outcomes. Furthermore, synbiotics have been reported to optimize feed utilization without necessarily increasing FI [24], which aligns with the results observed in this study where synbiotic-treated broilers showed a lower FI than the CON but a better FCR. In contrast, several studies have reported no significant effects of synbiotic supplementation on the growth performance of broiler chickens [25,26,27]. These inconsistencies in results may be due to variations in factors such as the genetic background of the birds, differences in probiotic strains and dosages, and the type and inclusion level of prebiotics used [28].
While not as impactful as probiotics, citric acid supplementation also improved growth performance. The increase in BW and BWG observed with citric acid agrees with studies that suggest organic acids can lower gastrointestinal tract pH, inhibit pathogenic bacteria, and improve nutrient digestibility [29,30]. The significant improvement in FI and FCR in the CA group compared to the CON group supports its beneficial effects on feed consumption and feed efficiency [9]. Similar effect on gosling was reported with citric acid supplementation [31]. In contrast, Ref. [32] reported that high doses of CA (40 and 60 g/kg diet) suppressed growth performance in broiler chickens, attributing these adverse effects to nutrient and mineral metabolism disruption. The improvements in FCR observed in both SB and PB groups are consistent with previous findings [33,34], where PB and SB treatments led to improved feed conversion. The synergistic effects of probiotics and prebiotics in synbiotics appear to enhance feed utilization efficiently, as observed in this study.
The results of the present study indicated no significant effects of CA, SB, and PB supplementation on broiler dressing percentage, meat yield (breast, thigh, and wing meat), or bone development (thigh, drumstick, and wing bones) compared to the control group. These findings are consistent with the observations of [35], who also reported no significant impact of probiotics on carcass yield. While the additive treatments in the current study may have primarily enhanced gut health and fat metabolism, they may not have significantly promoted protein synthesis or muscle growth, resulting in minimal effects on carcass yield [36]. The differences in results may be attributed to variations in the method of probiotic administration [37]; our study used drinking water, whereas others supplemented through the diet. Broilers in the CON group had a higher percentage of abdominal fat than those in the treated groups. This is consistent with the findings of Islam et al., and Elbaz et al. [38,39], although their studies did not report differences in carcass percentage between CON and PB groups.
A significant difference was observed in blood cholesterol and LDL levels among the different treatment groups when various additives were supplied in broiler drinking water. The CA, SB, and PB groups exhibited significantly lower cholesterol and LDL levels than the CON group. This finding is in line with previous studies, such as [40], who reported that probiotics administered via drinking water reduced plasma cholesterol and triglyceride concentrations. Similarly, Ref. [41] found that the supplementation of Lactobacillus sporogenes lowered serum cholesterol and LDL levels. CA supplementation led to significantly lower cholesterol and LDL levels compared to the CON group, aligning with previous reports [42]. However, opposite findings were reported by [43], who observed no significant effects of citric acid on cholesterol and LDL levels. While there is limited research on the effects of feed additives on serum biochemical parameters when delivered via drinking water, these results provide insights into the complex interactions between additives and broiler metabolism. Further studies are needed to clarify the effects of these additives on lipid profiles when administered through drinking water.
Although the tested feed additives demonstrated improved results compared to the control (CON) diet, their underlying mechanisms of action were not investigated in this study. Future research focusing on intestinal microbial populations and the digestibility of both macro- and micronutrients may provide valuable insights into how these additives enhance broiler performance.

5. Conclusions

In conclusion, all three supplementations in drinking water improved broiler growth performance, with increased BWG and reduced FCR, where the highest BW, BWG, and best FCR were observed in the PB group. No significant differences were found in meat yield or organ weights, but all three groups showed better lipid profiles compared to the CON group. These results suggest that probiotics can enhance growth and feed efficiency the most in broilers, warranting further exploration of their metabolic effects.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/ani15081168/s1.

Author Contributions

Conceptualization, S.H., T.Y. and R.H.; methodology, S.H., R.R., B.K.B., F.Y. and S.D.; data curation, S.H., F.S.P., S.D., P.M.D., S.U.K. and F.Y.; data analysis, P.M.D., S.D. and S.A.S.; investigation, S.H.; writing, B.K.B., R.R. and S.U.K.; supervision, T.Y.; writing—review and editing, R.H. and R.R. All authors have read and agreed to the published version of the manuscript.

Funding

The research was conducted with the following grants: Science and Technology Innovation Talent Program (25JR6KA010); the Project on Science and Technology Innovation of Gansu Provincial Department of Education (2024QB-066); the Youth Mentor Fund of Gansu Agricultural University (GAU-QDFC-2023-02); the National Natural Science Foundation of China (No. 32060764); and the Discipline Team Project of Gansu Agricultural University (GAU-XKTD-2022-22).

Institutional Review Board Statement

The study was conducted according to the guidelines of the Declaration of Helsinki and approved by the Animal Ethics Committee of Hajee Mohammad Danesh Science and Technology University.

Informed Consent Statement

Not applicable.

Data Availability Statement

The original contributions presented in this study are included in the Supplementary Material. Further inquiries can be directed to the corresponding author.

Conflicts of Interest

The authors declare no conflicts of interest.

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Table 1. Ingredient and nutrient composition of experimental diets (“as is” basis) 1.
Table 1. Ingredient and nutrient composition of experimental diets (“as is” basis) 1.
ItemStarter (0–14 Days)Grower (15–35 Days)
Ingredients (%)
 Maize50.3253
 Rice polish8.0010.0
 Soybean29.0022.50
 Protein concentrates (CP, 60%)8.008.00
 Oyster shell1.001.00
 Salt0.300.25
 DL-Methionine (99%)0.200.18
 Lysine (98.5%)0.030.03
 Vitamin-mineral premix 20.250.25
 Soybean oil3.504.00
 Di calcium phosphate0.250.25
 Choline chloride (50%)0.100.10
Total100100
Analyzed Value
 ME Kcal/kg30503150
 CP%23.6620.59
 DM%89.6887.09
 Lys%1.051.06
 Met%0.650.63
 Met + Cys%1.000.92
 Ca%0.951.05
Available P%0.450.42
1 Provided per kg of complete diet: 37.5 mg Zn (as ZnSO4); 37.5 mg Mn (as MnO2); 37.5 mg Fe (as FeSO4•7H2O); 3.75 mg Cu (as CuSO4•5H2O); 0.83 mg I (as KI); and 0.23 mg Se (as Na2SeO3•5H2O). 2 Provided per kg of complete diet: 12,000 IU of vitamin A, 4000 IU of vitamin D3, 37.5 IU of vitamin E, 4.5 mg of vitamin K3, 2.2 mg of Thiamin, 1.2 mg of Rivoflavin, 3 mg of vitamin B6, 0.03 mg of vitamin B12, 50 mg of Niacin, 0.5 mg of Folic acid, 0.08 mg of Biotin and 13.5 mg of Ca-Pantothenate.
Table 2. Growth performance of broiler in different dietary treatments at different ages 1.
Table 2. Growth performance of broiler in different dietary treatments at different ages 1.
ParameterTreatments 2p-Value
CONCASBPB
Feed Intake
Week 1167.50 ± 1.33170.57 ± 4.51166.65 ± 3.47162.06 ± 5.250.856
Week 2537.34 ± 4.71535.11 ± 4.29535.94 ± 2.94534.12 ± 1.770.932
Week 3767.93 ± 2.45770.44 ± 0.66770.14 ± 0.93771.50 ± 0.360.366
Week 4829.70 ± 1.29826.52 ± 1.53828.35 ± 0.41827.78 ± 0.610.279
Week 5681.71 a ± 3.41631.80 b ± 4.74619.13 bc ± 4.59609.29 c ± 6.620.00
Overall2984.18 a ± 12.42934.44 c ± 10.092920.2 b ± 8.782904.75 bc ± 14.560.03
Body weight, g
Initial45.7 ± 0.0344.3 ± 0.0844.6 ± 0.0245.5 ± 0.050.923
Week 1206.78 ± 2.15211.53 ± 1.92209.58 ± 2.83212.57 ± 1.160.294
Week 2541.15 ± 6.09548.67 ± 6.98548.67 ± 4.98551.23 ± 2.680.607
Week 31062.46 ± 4.411051.47 ± 9.791047.32 ± 3.731069.68 ± 4.800.377
Week 41482.76 c ± 1.631496.65 bc ± 5.151503.86 b ± 8.481533.52 a ± 5.660.002
Week 51741.17 c ± 0.981771 ab ± 11.511772.68 b ± 10.901792.16 a ± 5.890.018
Body weight gain, g
Week 1161.06 ± 2.56167.23 ± 4.38164.98 ± 2.78167.07 ± 3.690.726
Week 2334.37 ± 4.05337.14 ± 5.06339.09 ± 5.22338.66 ± 2.430.864
Week 3521.31 ± 8.97502.80 ± 16.1498.65 ± 1.29518.45 ± 7.460.542
Week 4420.30 c ± 3.18445.18 b ± 12.18456.54 b ± 4.76463.84 a ± 8.240.021
Week 5258.41 c ± 2.44274.59 a ± 6.52268 b ± 2.53258.64 ab ± 3.390.047
Overall1695.47 c ± 8.661726.70 b ± 5.231728.08 ab ± 10.781746.66 a ± 7.640.027
Feed conversion ratio
Week 11.04 ± 0.021.02 ± 0.021.01 ± 0.010.97 ± 0.020.873
Week 21.61 ± 0.001.59 ± 0.011.58 ± 0.021.58 ± 0.020.481
Week 31.47 ± 0.021.54 ± 0.071.54 ± 0.001.49 ± 0.040.506
Week 41.97 a ± 0.011.85 bc ± 0.051.81 b ± 0.021.78 c ± 0.060.012
Week 52.64 a ± 0.022.32 ab ± 0.062.30 b ± 0.032.25 c ± 0.020.508
Overall1.74 a ± 0.031.66 b ± 0.081.65 b ± 0.041.62 c ± 0.090.042
1 Abbreviation: CON, Control; CA, Citric acid; SB, Synbiotic; PB, Probiotic. 2 Data are presented as mean ± SE. Data represent 25 birds/pen and 4 pens/treatment. a,b,c indicate differences between groups. p < 0.05 was considered as significant.
Table 3. Meat yield and bone development of broiler in different dietary treatments 1.
Table 3. Meat yield and bone development of broiler in different dietary treatments 1.
ParameterTreatments 2p-Value
CONCASBPB
Meat yield (%)
Dressing Percentage (%)58.37 ± 2.2457.10 ± 1.3256.82 ± 0.7858.41 ± 0.470.780
Breast meat20.12 ± 0.8417.89 ± 0.3518.36 ± 0.6820.15 ± 0.800.103
Thigh meat8.12 ± 0.137.77 ± 0.127.51 ± 0.148.07 ± 0.510.117
Drumstick meat6.39 ± 0.245.54 ± 0.195.30 ± 0.086.02 ± 0.400.062
Wing meat3.44 ± 0.043.27 ± 0.053.32 ± 0.053.39 ± 0.030.058
Bone development (%)
Thigh bone2.01 ± 0.152.04 ± 0.051.97 ± 0.041.93 ± 0.180.911
Drumstick bone2.84 ± 0.062.72 ± 0.072.88 ± 0.172.84 ± 0.040.691
Wing bone2.84 ± 0.062.91 ± 0.002.81 ± 0.093.07 ± 0.290.066
1 Abbreviation: CON, Control; CA, Citric acid; SB, Synbiotic; PB, Probiotic. 2 Data are presented as mean ± SE. Data represent 5 birds/replication pen. Total 20 birds/treatment.
Table 4. Blood biochemical parameters of broiler in different dietary treatments (mg/dL) 1.
Table 4. Blood biochemical parameters of broiler in different dietary treatments (mg/dL) 1.
ParameterTreatments 2p-Value
CONCASBPB
TC138.83 a ± 11.89108.96 b ± 1.53101.29 c ± 18.61112.62 b ± 5.940.013
Triglycerides82.03 ± 5.4282.03 ± 5.4267.34 ± 4.0065.30 ± 2.350.090
HDL37.06 ± 1.1037.76 ± 2.0637.28 ± 0.1433.48 ± 0.140.107
LDL88.93 a ± 10.9456.08 bc ± 0.2250.06 c ± 17.6362.62 b ± 6.580.039
1 Abbreviation: CON, Control; CA, Citric acid; SB, Synbiotic; PB, Probiotic; HDL, High-Density Lipoprotein; LDL, Low-Density Lipoprotein; TC, Total Cholesterol. 2 Data are presented as mean ± SE. Data represent 5 birds/replication pen. Total 20 birds/treatment. a,b,c indicate differences between groups. p < 0.05 was considered as significant.
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Hossain, S.; Biswas, B.K.; Das, S.; Pory, F.S.; Raut, R.; Yeasmin, F.; Khan, S.U.; Dipta, P.M.; Shuvo, S.A.; Yeasmin, T.; et al. Effects of Citric Acid, Synbiotic, and Probiotic Supplementation Through Drinking Water on Growth Performance, Carcass Yield, and Blood Biochemistry of Broiler Chickens. Animals 2025, 15, 1168. https://doi.org/10.3390/ani15081168

AMA Style

Hossain S, Biswas BK, Das S, Pory FS, Raut R, Yeasmin F, Khan SU, Dipta PM, Shuvo SA, Yeasmin T, et al. Effects of Citric Acid, Synbiotic, and Probiotic Supplementation Through Drinking Water on Growth Performance, Carcass Yield, and Blood Biochemistry of Broiler Chickens. Animals. 2025; 15(8):1168. https://doi.org/10.3390/ani15081168

Chicago/Turabian Style

Hossain, Shahadot, Biswajit Kumar Biswas, Subir Das, Faija Sadia Pory, Rabin Raut, Fatima Yeasmin, Sharif Uddin Khan, Prantho Malakar Dipta, Sabbir Alom Shuvo, Tahera Yeasmin, and et al. 2025. "Effects of Citric Acid, Synbiotic, and Probiotic Supplementation Through Drinking Water on Growth Performance, Carcass Yield, and Blood Biochemistry of Broiler Chickens" Animals 15, no. 8: 1168. https://doi.org/10.3390/ani15081168

APA Style

Hossain, S., Biswas, B. K., Das, S., Pory, F. S., Raut, R., Yeasmin, F., Khan, S. U., Dipta, P. M., Shuvo, S. A., Yeasmin, T., & Hoque, R. (2025). Effects of Citric Acid, Synbiotic, and Probiotic Supplementation Through Drinking Water on Growth Performance, Carcass Yield, and Blood Biochemistry of Broiler Chickens. Animals, 15(8), 1168. https://doi.org/10.3390/ani15081168

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