Abstract:In order to study PQQ The efficacy of Na2 in improving the immune and antioxidant properties of commercial broiler chickens. 1440 healthy 1-day-old AA broiler chickens with similar body weight were selected and randomly divided into 6 treatments, with 6 replicates per treatment and 40 chickens per replicate (see Table 1). Treatment 1: Control group, fed with a corn soybean meal based basic diet; Processing 2, 3, 4, and 5, the control group was supplemented with PQQ on the same diet basis Na2 0.1,0.2,0.3,0.4 mg/kg； Treatment 6: The control group was supplemented with PQQ on the basis of the same diet Na2 (chemical synthesis) 0.2mg/kg. The experiment is divided into two stages (0-21d, 22-42d). Experimental chicken cage feeding, feeding pellet feed, with consistent dietary composition and nutritional levels between treatments. Experimental chickens were selected for 42 days, with 6 chickens randomly selected from each treatment (1 per replicate) for slaughter experiments. Serum, liver, and leg muscle samples were taken to measure antioxidant and immune performance. The measurement results indicate that:

Antioxidant properties: Adding PQQ to the diet of commercial broiler chickens Na2 and PQQ Na2 (chemical synthesis) significantly increased serum MDA content and liver SOD activity, while reducing leg muscle SOD activity and GSH activity (P<0.05). There was a trend of increasing serum GSH activity (P=0.080) and decreasing liver MDA content (P=0.078); With the increase of gradient addition, the MDA content in leg muscles showed a linear (P<0.05) and quadratic (P=0.085) decrease pattern. The serum MDA content, SOD activity, and GSH activity showed a quadratic increase, while the liver MDA content and leg muscle SOD activity showed a quadratic decrease (P<0.05). Comparing and analyzing numerically, with the antioxidant indicators of the control group at 100%, PQQ was added Na2 0.1,0.2,0.3,0.4 mg/kg and PQQ After Na2 (chemical synthesis), the MDA content increased by 66.71%, 51.25%, 78.67%, 42.86%, and 24.52% in serum, decreased by 7.39%, 7.63%, 4.93%, 5.97%, and increased by 9.09% in liver, and decreased by 9.95%, 9.37%, 13.08%, 16.2%, and 27.71% in leg muscles, respectively; SOD activity: Serum increased by 2.21%, 16.39%, 7.59%, 7.95%, and decreased by 4.48%, while liver increased by 13.31%, 11.13%, 29.47%, 4.38%, and 17.94%, respectively. Leg muscles decreased by 24.53%, 25.02%, 15.22%, 21.19%, and 17.04%, respectively; GSH activity: Serum increased by 38.39%, 26.31%, 39.96%, 27.62%, 18.53%, liver decreased by 14.95%, 7.94%, 7.98%, 2.15%, 9.67%, leg muscles decreased by 20.01%, 15.33%, 1.87%, 2.74%, 11.5%, respectively.

Immune performance: Adding PQQ to the diet of commercial broiler chickens Na2 and PQQ Na2 (chemical synthesis) significantly increased the levels of serum IgA, IgG, and IgM, as well as the content of complement protein 3, while reducing the content of complement protein 4 (P<0.05). And as the gradient increases, the IgA content shows a quadratic increase pattern, the IgG and IgM content shows a linear and quadratic change pattern (P<0.05), and the complement protein 4 content shows a quadratic change pattern (P<0.01). Comparing and analyzing numerically, with the control group's immunoglobulin indicators at 100%, PQQ was added Na2 0.1,0.2,0.3,0.4 mg/kg and PQQ After Na2 (chemical synthesis), the serum IgA content increased by 2.50%, 2.59%, 5.44%, 1.43%, 0.07% respectively, the IgG content increased by 1.27%, 4.49%, 3.79%, 1.50%, 4.16% respectively, and the IgM content increased by 7.65%, 7.94%, 0.72%, 0.66%, 0.35% respectively. The content of complement protein 3 increased by 2.67%, 1.16%, 2.90%, -1.08%, and 2.34%, respectively, while the content of complement protein 4 decreased by 5.78%, 4.48%, 7.41%, 0.23%, and 3.12%, respectively.

Keywords: commercial broiler chicken, PQQ. Na2, antioxidant performance, immune performance.

1. Materials and Methods

1.1  Test Materials

PQQ.Na₂:  Provided by Shandong Jincheng Biopharmaceutical Co., Ltd;

1.2  Experimental animals and design

1440 healthy 1-day-old AA broiler chickens with similar body weight were selected and randomly divided into 6 treatments, with 6 replicates per treatment and 40 chickens per replicate (see Table 1). Treatment 1: Control group, fed with a corn soybean meal based basic diet; Processing 2, 3, 4, and 5, the control group was supplemented with PQQ on the same diet basis Na2 0.1,0.2,0.3,0.4 mg/kg； Treatment 6: The control group was supplemented with PQQ on the basis of the same diet Na2 (chemical synthesis) 0.2mg/kg. Experimental chicken cage feeding, feeding pellet feed, free feeding and drinking.

1.3  Experimental diet

Temporarily missing

1.4  Test Method

Feeding experiment:The experiment is divided into two stages: broiler chickens (0-21d) and broiler chickens (22-42d). Experimental chicken cage breeding, with 2 cages per replicate and 20 chickens per cage. Feed pellet feed.

    Slaughter experiment:At the end of the feeding experiment (42 days), 6 chickens were randomly selected from each treatment for slaughter.

1.5 Measurement indicators

Antioxidant indicators:On the 42nd day of the experiment, 6 chickens were selected for slaughter in each treatment, serum samples were collected, liver and leg muscle samples were taken, and antioxidant indicators (T-SOD, T-GSH, and MDA) were measured.

Serum immune indicators:On the 42nd day of the experiment, 6 chickens were randomly selected for each treatment, and serum samples were collected to measure the levels of immunoglobulin A (IgA), immunoglobulin G (IgG), immunoglobulin M (IgM), as well as complement C3 and complement C4.

1.6 Data statistics and analysis

The data was analyzed using SAS (SAS Institute, 2000) software, and Duncan's multiple range test was used to compare the mean values, with a significance level of P=0.05. Using linear regression analysis to establish a regression model to determine the variation patterns (linear and quadratic) of various indicators under different additives and levels of additives.

2 Results and Analysis

2.1 Comparative analysis of antioxidant performance

Supplementing PQQ in the diet of commercial broiler chickens Na2 and PQQ The impact of Na2 (chemical synthesis) on its antioxidant properties is shown in Tables 2 and 3. Analysis of variance shows that adding PQQ to the diet of commercial broiler chickens Na2 and PQQ Na2 (chemical synthesis) significantly increased serum MDA content and liver SOD activity, while reducing leg muscle SOD activity and GSH activity (P<0.05). There was a trend of increasing serum GSH activity (P=0.080) and decreasing liver MDA content (P=0.078); With the increase of gradient addition, the MDA content in leg muscles showed a linear (P<0.05) and quadratic (P=0.085) decrease pattern. The serum MDA content, SOD activity, and GSH activity showed a quadratic increase, while the liver MDA content and leg muscle SOD activity showed a quadratic decrease (P<0.05). Comparing and analyzing numerically, with the antioxidant indicators of the control group at 100%, PQQ was added Na2 0.1,0.2,0.3,0.4 mg/kg and PQQ After Na2 (chemical synthesis), the MDA content increased by 66.71%, 51.25%, 78.67%, 42.86%, and 24.52% in serum, decreased by 7.39%, 7.63%, 4.93%, 5.97%, and increased by 9.09% in liver, and decreased by 9.95%, 9.37%, 13.08%, 16.2%, and 27.71% in leg muscles, respectively; SOD activity: Serum increased by 2.21%, 16.39%, 7.59%, 7.95%, and decreased by 4.48%, while liver increased by 13.31%, 11.13%, 29.47%, 4.38%, and 17.94%, respectively. Leg muscles decreased by 24.53%, 25.02%, 15.22%, 21.19%, and 17.04%, respectively; GSH activity: Serum increased by 38.39%, 26.31%, 39.96%, 27.62%, 18.53%, liver decreased by 14.95%, 7.94%, 7.98%, 2.15%, 9.67%, leg muscles decreased by 20.01%, 15.33%, 1.87%, 2.74%, 11.5%, respectively. It can be seen that adding different levels of PQQ Na2 can improve antioxidant performance by increasing serum SOD and GSH activity, liver SOD activity, and reducing MDA content in the liver and leg muscles. However, it has a negative effect on serum MDA content, liver GSH activity, and leg muscle SOD and GSH activity; Add QQ Na2 (chemically synthesized) has the effect of improving serum GSH activity, liver SOD activity, and leg muscle MDA levels.

2.2 Comparative analysis of serum immune performance indicators

  Immunoglobulin:Supplementing PQQ in the diet of commercial broiler chickens Na2 and PQQ The effect of Na2 (chemical synthesis) on serum immunoglobulin is shown in Tables 4 and 5. Analysis of variance shows that adding PQQ to the diet of commercial broiler chickens Na2 and PQQ Na2 (chemical synthesis) significantly increased the levels of serum IgA, IgG, and IgM (P<0.05), and with the increase of the addition gradient, the IgA level showed a quadratic increase pattern, while the IgG and IgM levels showed linear and quadratic changes (P<0.05). Comparing and analyzing numerically, with the control group's immunoglobulin indicators at 100%, PQQ was added Na2 0.1,0.2,0.3,0.4 mg/kg and PQQ After Na2 (chemical synthesis), the serum IgA content increased by 2.50%, 2.59%, 5.44%, 1.43%, 0.07% respectively, the IgG content increased by 1.27%, 4.49%, 3.79%, 1.50%, 4.16% respectively, and the IgM content increased by 7.65%, 7.94%, 0.72%, 0.66%, 0.35% respectively.

Complement protein:PQQ added to the diet of commercial broiler chickens Na2 and PQQ Na2 (chemical synthesis) significantly increased the content of complement protein 3 and decreased the content of complement protein 4 (P<0.01), and with the increasing gradient of addition, the content of complement protein 4 showed a quadratic change pattern (P<0.01). Comparing and analyzing numerically, with the complement protein 3 and complement protein 4 content of 100% in the control group, PQQ was added Na2 0.1,0.2,0.3,0.4 mg/kg and PQQ After Na2 (chemical synthesis), the contents of complement protein 3 were 102.67%, 101.16%, 102.90%, 98.92%, and 102.34%, respectively, and the contents of complement protein 4 were 94.22%, 95.52%, 92.59%, 99.77%, and 96.88%, respectively.

3. Conclusion

3.1 Adding different levels of PQQ to commercial broiler chickens Na2 increased serum SOD and GSH activity, liver SOD activity, and decreased MDA content in liver and leg muscles. However, it increased serum MDA content, decreased liver GSH activity, and leg muscle SOD and GSH activity. QQ was added Na2 (chemical synthesis) only improved serum GSH activity, liver SOD activity, and leg muscle MDA content, showing negative effects on other indicators. Explanation: PQQ. Na2 has the effect of improving the serum and liver of commercial broiler chickens to a certain extent, and reducing the antioxidant performance of leg muscles; QQ. Na2 (chemical synthesis) may not have the effect of improving serum, liver, and leg muscles in broiler chickens.

3.2 Supplementing PQQ in the diet of commercial broiler chickens Na2 and PQQ Na2 (chemically synthesized) can enhance the immune ability of broiler chickens by increasing the levels of serum IgA, IgG, IgM, and complement C3. Comparison between different levels of addition, PQQ Na2 0.2-0.3mg/kg has a more significant effect

In summary, supplementing PQQ in the diet of commercial broiler chickens Na2 has improved the antioxidant properties of serum and liver, enhanced humoral immunity, and improved the disease resistance of broiler chickens.

Table 1 Experimental Design for Broiler Chickens