Abstract:

In this study, the effects of different levels of surfa Tid to broilers' diets on growth performance, slaughter performance, meat quality, serum biochemical and fat metabolism indexes were studied to evaluate the effectiveness of surfa Tid on broilers. A total of 648 one-day-old male AA broilers with an initial body weight of 42.43 ± 0.25 g were randomly divided into 6 treatments with 6 replicates per treatment and 18 birds per replicate. Corn-soybean meal basal diet was used in the experiment, and each treatment group was supplemented with 0, 50, 100, 150, 200 and 250 mg/kg surfa Tid, respectively. The experiment lasted for 42 days, which was divided into two stages: early stage (0-21 days) and late stage (22-42 days).

The results were as follows: (1) Growth performance: supplementation of 100 to 250 mg/kg surfa Tid significantly decreased F:G of broilers 0 to 21 days (P < 0.01), and supplementation of 100 to 200 mg/kg surfa Tid significantly decreased F:G of broilers 0 to 42 days (P < 0.05). (2) Slaughter performance: 100~150 mg/kg surfa Tid significantly increased the slaughter rate and full evisceration rate of broilers (P < 0.01). (3) Meat quality: 100~150 mg/kg surfa Tid significantly decreased the breast muscle pH at 24 h after slaughter (P < 0.01), 150~250 mg/kg surfa Tid significantly decreased the breast muscle drip loss at 24 h after slaughter (P < 0.05). 50~250 mg/kg surfa Tid significantly decreased the drip loss of leg muscle 24 h after slaughter (P < 0.05). (4) Serum biochemical and fat metabolism indexes: With the increase of dietary surfa Tid supplemental level, the serum TG content of broilers on the 21st day was significantly linearly decreased (P < 0.05). In summary, the addition of surfa Tid in the diet can improve the growth performance and meat quality of broilers, and improve the slaughter performance of broilers. The recommended dosage of surfa Tid in the diet is 100-150 mg/kg.

Key words: surfa Tid; Broiler chickens; Growth performance; Slaughter performance; Meat quality

1 Purpose

The purpose of this experiment was to test the effects of Surfa Tid on growth performance, slaughter performance and meat quality of broilers, and to evaluate the effectiveness of Surfa Tid on broilers.

2 Materials and methods

2.1 Test time and place

The experiment was conducted at the Animal testing Base of China Agricultural University in April 2023.

2.2 Test materials

Surfa Tid (Surfactin) was produced by Beijing Enhalor Biotechnology Co., LTD. Surfactin content was indicated as ≥6.0%.

2.3 Trial design

A total of 648 one-day-old male AA broilers with an initial body weight of 42.43 ± 0.25 g were randomly divided into 6 treatments with 6 replicates per treatment and 18 birds per replicate. The experiment lasted for 42 days and was divided into two stages: early stage (0-21 days) and late stage (22-42 days). A corn-soybean meal basal diet was used in the experiment. The basal diet of each treatment group was supplemented with 0, 50, 100, 150, 200 and 250 mg/kg of Surfa Tid, respectively.

2.4 Trial diet

Table 1 Basal diet composition (feeding basis, %)

Note: ¹ To provide per kilogram of compound feed: retinyl acetate, 9000 IU; Vitamin D₃, 3000 IU; DL-α-tocopherol acetate, 24 mg; menadione, 1.8 mg; thiamine, 2.0 mg; riboflavin, 5.0 mg; pyridoxine, 3.0 mg；cyanocobalamin, 0.1 mg; niacin, 40 mg; pantothenic acid，15 mg; folic acid, 1.0 mg; biotin, 0.05 mg; choline chloride, 500 mg; Fe, 80 mg; Cu, 20 mg; Zn, 90 mg; I, 0.35 mg; Se, 0.30 mg.

Table 2 Nutritional levels of experimental diets (feeding basis, %)

Note: ¹ Metabolizable energy is calculated, the rest is measured.

3 Results and analysis

3.1 Growth performance and mortality

Table 3 Effects of different levels of Surfa Tid on growth performance of broilers ¹

Note:¹ There was a significant difference between different lowercase letters in peer data (P < 0.05).

² IBW, Initial body weight; ADG, Average daily gain; ADFI, Average daily gain; F:G，ratio of feed consumption to gain.

3.2 Slaughter performance

Table 4 Effects of different levels of Surfa Tid on slaughter performance of broilers ¹, %

Note:¹ There was a significant difference between different lowercase letters in peer data (P < 0.05).

3.3 Meat quality

Table 5 Effects of different levels of Surfa Tid on meat quality of broilers

Note:¹ There was a significant difference between different lowercase letters in peer data (P < 0.05).

3.4 Serum biochemistry and fat metabolism

Table 6 Effects of different levels of Surfa Tid on serum biochemistry of broilers

Note: ¹ TP, total protein; ALB, albumin; GLB, globulin; AST, aspartate transaminase; ALT，alanine aminotransferase; ALP, alkaline phosphatase; GLU, glucose; UN，urine nitrogen.

Table 7 Effects of different dietary levels of Surfa Tid on fat metabolism of broilers, mmol/L

Note: ¹ TC，total cholesterol; TG, total glycerol; HDL-C, high density lipoprotein cholesterol; LDL-C, low-density lipoprotein cholesterol; vLDL-C, very low density lipoprotein cholesterol.

4 Conclusion:

Growth performance: Supplementation of 100 to 250 mg/kg Surfa Tid significantly decreased F:G of broilers 0 to 21 days (P < 0.01), and supplementation of 100 to 200 mg/kg Surfa Tid significantly decreased F:G of broilers 0 to 42 days (P < 0.05).

Slaughter performance: 100~150 mg/kg Surfa Tid significantly increased the slaughter rate and evisceration rate of broilers (P < 0.01).

Meat quality: 100~150 mg/kg Surfa Tid significantly decreased the breast muscle pH at 24 h after slaughter (P < 0.01), 150~250 mg/kg Surfa Tid significantly decreased the breast muscle drip loss at 24 h after slaughter (P < 0.05). 50~250 mg/kg Surfa Tid significantly decreased the drip loss of leg muscle 24 h after slaughter (P < 0.05).

Serum biochemical and fat metabolism indexes: With the increase of dietary Surfa Tid supplemental level, the serum TG content of broilers on the 21st day was significantly linearly decreased (P < 0.05).

Surfa Tid^® is a microecological preparation successfully developed by Beijing Enhalor Biotechnology Research Institute and Tsinghua University with independent intellectual property rights. The product is prepared by using the natural strains of Bacillus subtilis that have been repeatedly selected, and by high density liquid aerobic fermentation, the strains are dried together with the metabolite subtilis surfactant. The use of Surfa Tid^® in feed improves immunity and promotes better animal health.