Cardioprotective and Hepatoprotective Activity of Silymarin in BroilerChickens Fed on Mash and Pellet Diets

Document Type : Nutrition - Hygiene

Authors

1 Department of Clinical Science, School of Veterinary Medicine, Shiraz University, Shiraz, Iran,

2 Department of Clinical Science, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

3 Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

Abstract

 
BACKGROUND: The liver and heart are two main damaged organs in ascites syndrome in fast -growing broilers. Using silymarin with a protective effect on the liver and heart may be a beneficial strategy to decrease ascites-induced mortality.
OBJECTIVES:
The present study assessed the cardiohepatic effects of silymarin in broilers fed on mash and pellet diets by assessing electrocardiographic (ECG) indices and some serum biochemical parameters.
METHODS:
A total of 120 Arbor Acres chicks were allocated to 6 groups and treated as follows: basal mash diet (CM); basal pellet diet (CP); silymarin at 500 ppm of mash (M500) and pellet diets (P500); and silymarin at 2500 ppm of mash (M2500) and pellet diets (P2500).
RESULTS:
CP had higher serum activities of aspartate aminotransferase, alanine aminotransferase, and creatine kinase MB (CK-MB) enzymes compared to CM (p <0.05). P2500 had a higher total protein and lower aspartate aminotransferase, alanine aminotransferase, and CK-MB compared to CP (p <0.05). T-duration, ST-segment, and R-R intervals were longer in CP compared to CM and were shorter in P2500 than in CP and P500 (p <0.05).
CONCLUSIONS:
The pellet diet led to changes in some biochemical and ECG indices in broilers, and silymarin at the 2500 ppm dose can be used as a hepatoprotective and cardioprotective compound to modulate cardiohepatic failure in susceptible broilers.

Keywords


Article Title [فارسی]

فعالیت محافظت کننده قلب و محافظت کننده کبد عصاره سیلی مارین در جوجه های گوشتی تغذیه شده با جیره آردی و پلت

Authors [فارسی]

  • سیده عالمه حسینیان 1
  • بهمن عبدی هاچسو 2
  • سعید نظیفی 3
  • سید امیر هاشمی هزاوه 2
  • سید حمیدرضا هاشمی تبار 2
  • رضا رضاپور 3
1 گروه علوم درمانگاهی، دانشکده دامپزشکی، دانشگاه شیراز، شیراز، ایران
2 گروه علوم درمانگاهی، دانشکده دامپزشکی، دانشگاه شیراز، شیراز، ایران
3 گروه علوم درمانگاهی، دانشکده دامپزشکی، دانشگاه شیراز، شیراز، ایران
Abstract [فارسی]

زمینه مطالعه:  کبد و قلب دو عضو اصلی آسیب دیده در سندرم آسیت در جوجه‌های گوشتی است. استفاده از سیلی‌مارین با اثر محافظتی بر کبد و قلب ممکن است یک راهکار مفید برای کاهش مرگ و میر ناشی از آسیت باشد.
هدف: مطالعه حاضر با بررسی شاخص‌های ECG و برخی از پارامترهای بیوشیمیایی سرم، اثرات قلبی-کبدی سیلی‌مارین را در جوجه‌های گوشتی تغذیه شده با رژیم غذایی آردی و پلت ارزیابی کرد.  
روش کار: تعداد 120 قطعه جوجه نژاد آربراکرز به شش گروه تقسیم شدند: رژیم غذایی پایه آردی (CM)، رژیم غذایی پایه پلت (CP)، سیلی‌مارین در دوز ppm 500 جیره‌های آردی (M500) و پلت (P500)، سیلی‌مارین در دوز  ppm2500 جیره‌های آردی (M2500) و پلت (P2500).
نتایج: CP فعالیت سرمی بالاتری از آنزیم‌های آسپارتات آمینو ترانسفراز، آلانین امینوترانسفراز، و کراتین کیناز در مقایسه با CM داشت (05/0p < /em><). P2500 پروتئین کل بالاتر و آسپارتات آمینو ترانسفراز، آلانین امینوترانسفراز، و کراتین پایین‌تری نسبت به CP داشت (05/0p < /em><). مدت زمان T، قطعه ST و فاصله R-R به‌طور معنی‌‎دار در CP در مقایسه با CM بیشتر و در  P2500کوتاه تر از CP و P500 بود (05/0p < /em> <).
نتیجه‌گیری نهایی: جیره پلت در جوجه‌های گوشتی منجر به تغییر برخی از شاخص‌های بیوشیمیایی و الکتروکاردیوگرافی می‌شود و سیلی‌مارین با دوزppm  2500 می‌تواند به‌عنوان یک ترکیب محافظت‌کنندۀ کبد و قلب جهت تعدیل نارسایی قلبی- کبدی در جوجه‌های گوشتی حساس استفاده شود.

Keywords [فارسی]

  • ارزیابی قلبی
  • ارزیابی کبدی
  • جیره آردی
  • جیره پلت
  • سیلی مارین

Introduction

The genetic selection has led to a fast growth rate in modern strains of broiler chickens (Ahmadipour et al., 2015). In fast-growing broilers, the metabolic rate and the requirement of oxygen are increased, and the heart and lungs are not capable of providing enough oxygen, which causes metabolic disorders (Wideman et al., 2013). Right ventricular failure (RVF) and ascites syndrome are the most prominent metabolic disorders, commonly seen in broiler chickens with a high-growth rate (Ahmadipour et al., 2019).

Diet form (pellet, mash, and crumble) is one of the most important effective factors on the incidence of RVF and ascites in broilers (Sahraei, 2014). Broilers fed on the pellet diet present higher weight gain and better feed conversion ratio compared with those fed the mash diet (Amerah et al., 2008). Several studies have stated that susceptibility to RVF and ascites was higher in birds fed pelleted diets than in birds received mash diets (Jafarnejad et al., 2010; Sahraei, 2014). The heart and liver are two major damaged organs in RVF and ascites syndrome (Jafarnejad et al., 2010). Improving the health of the heart and liver using herbal extracts is a benefit and can be a clinical strategy to control RVF lesions and decrease RVF-induced mortality. Milk thistle is one of the more common medicinal herbs with protective effects on the liver and heart.

Milk thistle (Silybum marianum L., Asteraceae) is one of the most common herbs for the treatment of liver diseases (Schrieber et al., 2008). The seed and fruit of milk thistle contain silymarin that shows a variety of pharmacological activities, as well as antioxidant, anti-inflammatory, antibacterial, and antiviral properties in many experimental and clinical studies (Koçarslan et al., 2016).

Some studies have evaluated the positive effects of silymarin extract on growth performance and hepatic disorders in broilers (Schiavone et al., 2007; Kralik et al., 2015; Hosseinian et al., 2020). Further, various researches have established that silymarin had cardioprotective activity due to its antioxidant content in laboratory animals (Rao & Viswanath, 2007; Al-Rasheed et al., 2014; Koçarslan et al., 2016). However, there is a lack of knowledge about the positive effects of silymarin on broiler’s heart health. Evaluating heart electrical activity by electrocardiogram (ECG) is a simple method to assess heart health in birds (Yogeshpriya et al., 2018).

In veterinary medicine, there are several diagnostic tools for the evaluation of cardiac abnormalities, but ECG is one of the most useful and non-invasive techniques, which gives significant information about heart rate (HR), cardiac arrhythmias, and electrical conductance abnormalities (Cushing et al., 2013; Yogeshpriya et al., 2018).

In avian medicine, ECG is a useful tool utilized to measure HR and detect cardiac arrhythmias and cardiac chamber enlargement (Sharifi et al., 2015; Hosseinian et al., 2019). Several studies have indicated that RVF and ascites syndrome induce a change in the morphology of ECG waves in broilers, and they used ECG to detect and diagnosis the ascites syndrome (Hassanpour et al., 2009; Yousefi et al., 2013).

In this study, broilers were fed with two different forms of diet (mash and pellet), and heart and liver health was evaluated by assessing some serum biochemical and ECG induces. Also, the effects of two different doses of dietary silymarin (500 and 2500 ppm) were assessed on some serum parameters and ECG. In this research, this hypothesis was assessed that pellet diet can be led to heart and liver dysfunction in broilers, and silymarin could attenuate the cardiac and hepatic damages.

The results of the present study may clarify the protective effects of silymarin on the liver and heart in fast-growing broilers, and silymarin can be used as a cardioprotective and hepatoprotective compound during the rearing period of susceptible broilers to ascites syndrome.

Materials and Methods

Birds and Treatment Groups

This experiment was performed at the Veterinary College of Shiraz University. A total of 120 1-day-old Arbor Acres broiler chicks were used for the experiment and reared for 42 days. During study, broilers were raised in environmentally controlled rooms under standard environmental conditions suggested by commercial recommendations of the chick producer company (Aviagen, 2018).

On day 14 of the experiment, birds were weighed and randomly assigned into 6 equal groups (n=20) with five replicates. The treatment groups consisted of supplementation with silymarin extract in the mash and pelleted diets as follows: the control mash group (basal mash diet [CM], fed on a mash diet without silymarin), control pellet (basal pellet diet [CP], fed on a pellet diet without silymarin), two doses of silymarin in mash feed (silymarin at 500 ppm of mash [M500] and silymarin at 2500 ppm of mash [M2500]), and two doses of silymarin in pellet feed (silymarin at 500 ppm of pellet [P500] and silymarin at 2500 ppm of pellet [P2500]).

In the present study, the basal diet was corn-soybean meal-based and formulated to meet or exceed the minimum National Research Council (NRC; 1994) Standards. The starter (0-10 days), grower (10-25 days), and finisher (25-42 days) feeds were used during the experiment. All birds were fed on a pellet diet during the first and second weeks of the experiment, and then two forms of diet (mash and pellet) with a similar composition of ingredients (see Table 1) were used from the third to sixth weeks of the experiment.

 

 

Table 1. Ingredients and composition of mixture feed (gkg-1)

     
  

Component

  
  

Diets

  

 

Starter

Grower

Finisher

Ingredients, %

 

 

 

Yellow Corn

53.4

58.0

61.3

Soybean meal (44%)

39.0

35.0

31.0

Dicalcium phosphate

1.7

1.5

1.3

CaCO3 (38%)

1.7

1.4

1.3

Sunflower oil

3.0

3.0

4.0

Sodium chloride

0.3

0.3

0.3

Methionine

0.2

0.15

0.15

Lysine

0.2

0.15

0.15

Premix*

0.5

0.5

0.5

Total

100

100

100

Nutrient levels

 

 

 

ME, kcal/kg

2900

3000

3100

Crude protein, %

22

20.5

19

Calcium, %

1.05

0.9

0.8

Available Phosphorus, %

0.5

0.45

0.4

Sodium, %

0.19

0.19

0.19

Lysine, %

1.31

1.25

1.14

Methionine, %

0.54

0.48

0.44

Threonine, %

0.85

0.81

0.75

Tryptophan, %

0.25

0.22

0.2

* Vitamin and mineral content per kilogram of premix: vitamin A: 3,600,000 IU; vitamin D3: 800,000 IU; vitamin E: 7,200 IU; vitamin K3: 0.8 g; vitamin B1: 0.71 g; vitamin B2: 2.64 g; vitamin B3: 3.92 g, vitamin B5: 11.88 g; vitamin B6: 1.176 g; vitamin B12: 6 mg; folic acid: 0.4 g; biotin: 40 mg; choline chloride: 100 g; selenium: 80 mg; cobalt: 100 mg; iodine: 396 mg; copper:4 g; zinc: 33.88 g; iron: 20 g; manganese: 39.68 g.

 

 

The used diets in this study was prepared in the livestock affairs of the Faculty of Veterinary Medicine, Shiraz University. Firstly, the feed was supplied based on NRC Standards for broilers. Then, a part of the feed was finely grounded, mixed, and used as a mash form in mash treatments during the entire the experiment, and the other part of the feed was pelleted in a steam pellet mill. After pelleting, the pelleted feed was dried and cooled to an average temperature of 37°C and used as a pellet form in pellet treatments during the entire the experiment. Feed and freshwater were supplied ad libitum during the entire experiment.

Silymarin powder was purchased from BarijEsans Company (Iran), containing 43.87% of silibinin and 96.76% dry matter and was added to mash and pellet diets from days 14 to 42 of the experiment. All diets contained neither anticoccidials nor any other medications.

The temperature was maintained at 32°C during the first week and reduced gradually until a constant temperature of 24°C was achieved. A 24-hour lighting schedule was used during the first week and then reduced gradually until 20 h light: 4 h darkness (20L:4D).

Blood Sampling

Ten apparently healthy birds of each group were selected, and blood sampling (5 mL/birds) was done from the brachial vein on days 21, 28, 35, and 42. Blood samples were kept at room temperature for 30 minutes, and then the clotted blood samples were centrifuged at 3000g for 10 minutes to separate sera. The clear sera were collected and stored at -20℃ until the biochemical analysis.

Evaluating Hepatic Parameters

The hepatic parameters, including total protein, albumin, globulin, uric acid, triglyceride, total cholesterol, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL), were measured by an automated analyzer (Alpha Classic, Sanjesh Company, Iran) using commercial clinical investigation kits (Pars Azmoon, Tehran, Iran). Moreover, the activity of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were evaluated using a commercial kit (Pars Azmoon, Tehran, Iran).

Evaluating Cardiac Parameters

Biochemical Assays

Calcium, magnesium, phosphorous, chloride, and creatine kinase MB (CK-MB) were measured using commercial kits (Pars Azmoon, Iran) and biochemical auto analyzer (Alpha Classic, Sanjesh Company, Iran). Sodium and potassium were determined using a flame photometer (Clinical flame photometer, Fater Company, Iran).

Electrocardiographic Studies

From each group, 7 apparently healthy chicks were randomly selected on 21, 28, 35, and 42 days, and ECGs were recorded by a single channel ECG machine (Kenz-line EKG 110, Suzuken Company, Japan). The ECG measurements were obtained from unanesthetized and restrained birds in a standing position. Before ECG recording, the chickens rested for about 5 minutes to calm down. ECG gel was applied to the skin, and then alligator clip electrodes were positioned at the base of the right and left wings and gastrocnemius muscle of the right and left limbs (Yogeshpriya et al., 2018).

All ECGs were recorded using a calibration of 10 mm/mV and a paper speed of 50 mm/sec (Reddy et al., 2016). ECGs were recorded by different leads, including I, II, III, and aVR, aVL, and aVF for every chicken. In birds, lead II is commonly used to evaluate waves' morphology in ECG (Reddy et al., 2016). For this reason, the amplitude and duration of P, T, R, and S waves, as well as the duration of QT, R-R, PR, and ST intervals, in each bird of the present experiment were measured from lead II as a standard lead (Reddy et al., 2016). Finally, HR was measured in each bird.

Statistical Analysis

The statistical analysis was performed using SPSS 22 (SPSS Inc., Chicago, Ill., USA). In the present study, the data from various serum parameters and ECG indices were analyzed by 1-way analysis of variance (ANOVA). The data were presented as mean ± SE. The significance level was set as P-value<0.05.

Results

The results of serum hepatic parameters are presented in Tables 2 and 3.

As seen in Table 2, total protein and albumin significantly decreased in CP compared with CM at some times of the experiment (P<0.05). P500 and P2500 significantly had a higher total protein compared with CP on days 28, 35, and 42. Circulating uric acid increased significantly in CP and P500 compared with CM. In this experiment, P2500 had a lower level of uric acid compared to CP and P500. The serum activity of ALT and AST enzymes in the CP group was significantly higher than in CM, and the activity levels of ALT and AST decreased significantly in P2500 compared to CP on day 42 (P<0.05) (Table 2).

 

 

Table 2. Circulating hepatic parameters (mean±SE) of broiler chickens (n=20) following dietary supplementation of pellet and mash diets by silymarin extract.

        
  

Parameters

  
  

Days

  
  

Groups (mean ±SE)

  

CM

M500

M2500

CP

P500

P2500

Total protein

(gr/L)

21

2.43±0.071a

2.92±0.022a

2.13±0.040a

2.80±0.041a

3.12±0.080b

2.72±0.101a

28

3.47±0.092a

3.35±0.073a

2.89±0.033b

2.25±0.072b

3.46±0.052a

3.70±0.081a

35

2.80±0.051a

2.94±0.072a

2.94±0.022a

2.59±0.074a

3.09±0.084b

3.01±0.017b

42

3.72±0.091a

3.98±0.020a

3.87±0.080a

2.28±0.038b

3.36±0.063a

3.92±0.043a

Albumin

(gr/L)

21

1.37±0.031a

1.34±0.040a

1.21±0.062a

1.42±0.035a

1.52±0.023a

1.42±0.044a

28

1.40±0.064a

1.46±0.016a

1.39±0.074a

1.57±0.051a

1.19±0.065a

1.42±0.065a

35

1.37±0.087a

1.38±0.055a

1.39±0.020a

1.22±0.050a

1.28±0.066a

1.32±0.022a

42

2.43±0.034a

2.47±0.054a

2.44±0.020a

1.26±0.120b

1.36±0.074b

1.92±0.060b

Globulin

(gr/L)

21

1.08±0.170a

1.54±0.068a

0.97±0.114a

1.39±0.081a

1.68±0.123a

1.37±0.205a

28

1.42±0.080a

1.74±0.125a

1.48±0.065a

1.68±0.112a

1.05±0.115a

1.60±0.144a

35

1.53±0.111a

1.61±0.164a

1.25±0.176a

1.69±0.142a

1.63±0.121a

1.68±0.135a

42

1.27±0.201a

1.58±0.097a

1.36±0.078a

1.40±0.163a

1.73±0.130a

1.39±0.084a

Uric acid

(mg/dL)

21

2.83±0.225a

3.58±0.189b

2.85±0.197a

3.23±0.305b

4.60±0.404c

3.98±0.513b

28

3.22±0.297a

3.95±0.348a

3.85±0.135a

4.51±0.434b

2.71±0.175c

3.80±0.305a

35

3.94±0.271a

3.92±0.313a

4.09±0.491a

3.72±0.300a

4.55±0.424b

3.71±0.294a

42

3.90±0.519a

4.21±0.190b

3.28±0.294a

4.26±0.455b

4.08±0.313b

3.20±0.315a

Alanine aminotransferase (IU/L)

21

126.84±9.110a

122.60±9.158a

99.45±3.780b

125.39±8.937a

121.44±4.844a

128.55±4.385a

28

127.88±7.910a

129.29±7.856a

110.88±6.125b

132.79±3.809a

129.98±4.496a

125.01±6.147a

35

128.04±9.747a

124.55±6.144a

97.58±3.751b

132.88±6.568a

119.57±4.728a

109.29±6.446a

42

97.88±5.887a

112.45±6.783b

109.11±5.360b

128.19±4.018b

130.01±3.950b

95.48±5.010a

Aspartate aminotransferase

(IU/L)

21

253.70±10.317a

245.60±10.958a

199.90±7.888b

258.30±8.178a

242.90±9.981a

248.30±6.480a

28

252.80±8.015a

257.20±8.154a

240.00±12.125b

265.70±6.906a

259.90±7.410a

249.70±10.744a

35

240.30±10.846a

242.40±11.541a

193.20±6.785b

263.50±11.765a

229.70±7.027a

203.20±12.033b

42

199.50±6.812a

219.50±7.683b

207.90±8.664a

241.30±6.112b

247.90±8.255b

198.60±9.050a

CM: control mash diet (0 ppm silymarin); CP: control pellet diet (0 ppm silymarin); M500: mash diet + 500 ppm silymarin; M2500: mash diet + 2500 ppm silymarin; P500: pellet diet + 500 ppm silymarin; P2500: pellet diet + 2500 ppm silymarin; a,b,c Different letters in the superscripts of the same row indicate significant differences (P <0.05).

 

 

As seen in Table 3, the serum levels of total triglyceride, cholesterol, and LDL in supplemented groups (i.e., M500, M2500, P500, and P2500) decreased significantly compared to CM and CP groups (P<0.05). The CP group had lower concentrations of VLDL and LDL compared to the CM group.

 

 

Table 3Circulating hepatic indices (mean±SE) of broiler chickens (n=20) following dietary supplementation of pellet and mash diets by silymarin extract.

        
  

Parameters

  
  

Days

  
  

Groups (mean ±SE)

  

CM

M500

M2500

CP

P500

P2500

Triglyceride

(mg/dL)

21

85.70±1.820a

87.70±3.285a

62.80±1.655b

83.30±3.850a

77.50±1.22b

63.00±2.35b

28

85.70±3.180a

71.50±1.980b

79.00±3.996b

72.50±1.544b

55.80±1.96c

66.90±1.49b

35

76.40±1.431a

64.70±1.321b

66.20±2.027b

84.90±1.242c

65.40±1.65b

63.40±3.91b

42

83.80±1.262a

73.50±1.825b

62.40±3.221c

89.10±2.19a

72.50±1.65b

60.40±3.91c

Cholesterol

(mg/dL)

21

148.50±2.39a

100.80±6.32b

98.50±2.551b

145.60±2.16a

101.50±2.54b

103.20±3.1b

28

148.50±2.71a

122.80±2.51b

122.40±2.03b

144.30±3.74a

96.10±2.640c

122.50±3.8b

35

139.40±2.64a

110.70±3.48b

107.60±4.62b

139.50±3.09a

100.70±3.49b

97.20±3.87b

42

135.20±1.24a

116.00±2.13b

105.40±2.24c

143.20±3.20a

113.90±1.71b

93.30±2.58c

HDL

(mg/dL)

21

70.60±1.07a

78.20±0.284a

71.10±1.425a

70.90±0.704a

71.70±1.094a

74.20±0.520a

28

70.90±0.92a

72.60±0.921a

76.00±0.285a

71.40±1.175a

70.30±0.975a

77.30±0.634a

35

75.30±0.25a

70.30±0.908a

70.80±1.034a

75.00±0.870a

76.00±0.891a

70.90±0.910a

42

67.10±1.09a

74.20±0.169a

71.30±0.363a

70.00±1.954a

73.10±1.208a

71.40±1.097a

LDL

(mg/dL)

21

93.00±2.23a

58.70±2.41b

54.80±1.27b

81.20±1.944c

55.90±1.50b

51.00±1.74b

28

85.60±0.64a

54.00±1.38b

59.60±1.34b

77.70±1.485a

53.40±0.21b

60.50±1.47b

35

89.80±0.45a

53.20±2.43b

49.50±2.20b

71.70±1.853c

56.70±1.79b

52.70±1.30b

42

91.50±1.40a

55.80±2.187c

49.90±0.372c

75.60±1.05b

50.50±1.660c

57.70±1.950c

VLDL

(mg/dL)

21

17.06±0.43a

18.13±0.588a

12.54±0.638c

15.52±0.95b

15.68±0.25b

12.65±0.594c

28

17.19±0.67a

14.29±0.18b

16.58±0.780a

14.99±0.36b

11.05±0.966c

13.28±0.49b

35

15.24±0.48a

12.98±0.52b

13.24±0.45b

16.90±0.818a

13.80±0.95b

12.65±0.73b

42

16.80±0.36a

14.72±0.37b

12.40±0.676c

17.80±0.890a

14.54±0.190b

12.31±0.760c

Total billirubin

(mg/dL)

21

0.46±0.024c

0.51±0.014b,c

0.42±0.011a,c

0.50±0.074b

0.55±0.104b

0.48±0.081a,c

28

0.48±0.078b

0.51±0.076a,b

0.51±0.050a,b

0.56±0.090a

0.44±0.054c

0.49±0.041b,c

35

0.51±0.017a

0.51±0.074a

0.50±0.104a

0.50±0.012a

0.54±0.031a

0.50±0.032a

42

0.46±0.019a

0.58±0.020b

0.50±0.024a

0.51±0.090a,b

0.53±0.080a,b

0.49±0.071a,b

Direct billirubin

(mg/dL)

21

0.03±0.011a,b

0.02±0.003b

0.03±0.011a,b

0.03±0.004a,b

0.02±0.006a,b

0.04±0.001a

28

0.04±0.020a

0.04±0.003a

0.03±0.021a

0.03±0.007a

0.03±0.003a

0.03±0.002a

35

0.03±0.000a

0.04±0.001a

0.03±0.002a

0.03±0.005a

0.04±0.004a

0.04±0.003a

42

0.04±0.002a

0.03±0.011a

0.03±0.004a

0.03±0.004a

0.03±0.003a

0.03±0.001a

CM: control mash diet (0 ppm silymarin); CP: control pellet diet (0 ppm silymarin); M500: mash diet + 500 ppm silymarin; M2500: mash diet + 2500 ppm silymarin; P500: pellet diet + 500 ppm silymarin; P2500: pellet diet + 2500 ppm silymarin; HDL: high-density lipoprotein cholesterol; LDL: low-density lipoprotein cholesterol; VLDL: very low-density lipoprotein cholesterol; a,b,c Different letters in the superscripts of the same row indicate significant differences (P <0.05).

 

 

Serum Cardiac Parameter Analysis

The results of serum cardiac parameters are presented in Table 4.

The circulating levels of calcium and phosphorus were significantly lower in the CP group than in other groups on 28, 35, and 42 days (P<0.05). P500 and P2500 had significantly higher concentrations of calcium and phosphorus compared with CP (P<0.05). CP had a higher activity of CK enzyme compared with CM on day 42, and P500 and P2500 had a lower serum activity of CK compared with CP (P<0.05) (Table 4).

 

 

Table 4Circulating electrolytes and cardiac parameters (mean±SE) of broiler chickens (n=20) following dietary supplementation of pellet and mash diets by silymarin extract.

        
  

Parameters

  
  

Days

  
  

Groups (mean ±SE )

  

CM

M500

M2500

CP

P500

P2500

Calcium

( mg/dL)

21

5.71±0.180a

5.09±0.354a

3.99±0.354b

5.28±0.091a

6.66±1.771c

5.7±0.721a

28

7.28±0.020a

7.39±0.092a

6.94±0.101a

5.45±0.011b

6.88±0.082a

7.09±0.062a

35

6.31±0.116a

6.03±0.093a

6.57±0.230a

4.28±0.081b

6.36±0.482a

6.32±0.240a

42

7.79±0.064a

7.79±0.151a

7.05±0.192a

5.14±0.060b

7.22±0.033a

7.84±0.120a

Phosphorus

(mg/dL)

21

4.90±0.351a

4.79±0.350a

4.56±0.231a

5.15±0.304a

5.23±0.304a

4.79±0.323a

28

6.09±0.101a

5.32±0.111a

5.63±0.122a

4.63±0.151b

4.61±0.082b

5.80±0.062a

35

5.59±0.102a

5.35±0.082a

5.77±0.113a

3.17±0.052b

5.05±0.044a

5.25±0.060a

42

6.72±1.130a

5.99±0.203a

5.12±0.314b

4.78±0.343b

5.67±0.332a

6.89±0.330a

Sodium

(mmol/L)

21

125.53±3.880a

122.33±5.540a

129.76±5.34a

119.98±8.981a

111.28±3.990a

113.98±6.184a

28

130.45±4.431a

129.87±7.011a

138.65±9.89a

112.23±6.941b

119.63±5.844b

115.23±6.44b

35

132.98±5.211a

132.13±8.902a

128.51±7.09a

119.98±7.862b

129.47±7.012a

142.78±6.961c

42

140.89±10.09a

132.44±5.985a

130.87±9.89a

123.67±9.321b

119.17±8.330b

143.97±7.920a

Potassium

(mg/dL)

21

4.87±1.06a

4.56±2.032a

5.01±1.234a

4.88±0.985a

4.77±1.094a

4.61±0.285a

28

4.78±0.984a

3.99±1.014a

4.66±2.135a

4.35±0.691a

4.98±1.971a

4.09±0.325a

35

4.90±0.214a

4.52±1.124a

4.87±3.095a

5.01±0.274a

4.81±0.542a

4.62±0.477a

42

4.98±0.792a

5.06±3.095a

4.72±2.017a

4.55±0.936a

4.76±0.437a

4.72±0.732a

Magnesium

(mg/dL)

21

1.88±0.091a

2.15±0.067a

1.84±0.065a

2.02±0.071a

2.25±0.134a

2.06±0.134a

28

2.07±0.084a

2.31±0.085a

2.22±0.046a

2.23±0.060a

1.85±0.062a

2.29±0.085a

35

2.41±0.072a

2.38±0.076a

2.40±0.057a

2.26±0.074a

2.22±0.045a

2.39±0.066a

42

2.52±0.033a

2.55±0.044a

2.62±0.070a

2.16±0.052a

2.29±0.080a

2.54±0.070a

Chloride

(mmol/L)

21

105.30±0.225a

103.90±0.455a

107.50±0.445a

105.70±0.512a

107.50±0.664a

106.80±0.53a

28

106.70±0.650a

108.70±0.346a

105.80±0.323a

104.60±0.380a

110.30±0.415a

106.30±0.47a

35

107.80±0.642a

109.40±0.854a

103.90±0.327a

104.50±0.514a

108.50±0.865a

108.30±0.44a

42

104.80±0.337a

106.20±0.473a

105.10±0.610a

103.80±0.515a

107.40±0.534a

108.30±0.49a

CK-MB

(IU/L)

21

1481.80±12.890a

1474.50±10.081a

1235.22±13.06b

1307.17±6.181c

1348.80±9.990c

1344.80±3.361c

28

1482.50±17.780a

1303.90±14.632b

1482.10±19.43a

1328.60±12.710b

1201.40±12.114c

1377.60±22.96b

35

1491.10±27.841a

1289.00±15.462b

1260.80±18.7b

1485.00±12.227a

1447.60±17.893a

1214.00±19.28b

42

1288.80±14.021a

1126.50±19.803b

1108±21.130b

1644.30±20.360c

1443.80±11.870d

1332.95±10.25a

CM: control mash diet (0 ppm silymarin); CP: control pellet diet (0 ppm silymarin); M500: mash diet + 500 ppm silymarin; M2500: mash diet + 2500 ppm silymarin; P500: pellet diet + 500 ppm silymarin; P2500: pellet diet + 2500 ppm silymarin; CK-MB: creatine kinase MB; a,b,c Different letters in the superscripts of the same row indicate significant differences (P <0.05).

 

 

Electrocardiographic Analysis

All ECG leads (6 leads) of the broilers in various groups seen in Figure 1. The durations and amplitudes of all waves in lead II are presented in Table 5.