Application of dendrobium officinale polysaccharide as feed additive for largemouth bass

Abstract

The invention relates to application of dendrobium candidum polysaccharide as a largemouth bass feed additive, the dendrobium candidum polysaccharide is added into largemouth bass feed, and the content of the dendrobium candidum polysaccharide is less than or equal to 2.5 g in every 1 kg of feed. Dendrobium officinale is added into the feed, so that growth can be promoted, liver and intestine health can be regulated, and the survival rate can be increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of feed, more particularly, it relates to application of dendrobium officinale polysaccharide as feed additive of largemouth bass. BACKGROUND

[0002] Largemouth bass, also known as American bass or California bass, is originally from North America and widely distributed in freshwater areas of the United States and Canada, especially in the Great Lakes region. At present, it is also cultured in China. Largemouth bass has important economic value because of its firm meat, delicious taste and few bones, and has become one of the important varieties of Chinese freshwater aquaculture, with broad market prospects and economic benefits. Feed plays an important role in the culture of largemouth bass. Dendrobium officinale is a traditional Chinese medicine with high medicinal value and also has certain application value in the field of animal feed. However, the current application of dendrobium officinale in feed is to add dendrobium officinale as a whole, and there is a lack of specific research. Therefore, the present application proposes the application of dendrobium officinale as a feed for largemouth bass. SUMMARY

[0003] In view of the deficiencies in the prior art, the purpose of the present application is to provide the application of dendrobium officinale polysaccharide as a feed additive for largemouth bass. The addition of dendrobium officinale in feed can promote growth, regulate liver and intestinal health and improve survival rate.

[0004] The above technical purpose of the present application is realized by the following technical scheme: The application of dendrobium officinale polysaccharide as a feed additive for largemouth bass adds dendrobium officinale polysaccharide in the feed of largemouth bass, wherein the content of dendrobium officinale polysaccharide in each 1 kg of feed is ≤2.5 g.

[0005] In one embodiment, the content of dendrobium officinale polysaccharide in each 1 kg of feed is ≤1 g.

[0006] In one embodiment, the content of dendrobium officinale polysaccharide in each 1 kg of feed is 0.5 g.

[0007] In one embodiment, the method of adding dendrobium officinale polysaccharide in largemouth bass is as follows: Dissolve the dendrobium officinale polysaccharide in water to obtain an additive solution; Add the additive solution to the basic feed, mix uniformly, then dry to obtain the feed for largemouth bass.

[0008] In one embodiment, the amount of water added is 10% of the total mass of the feed.

[0009] In one embodiment, the drying temperature is 40-50℃.

[0010] The large-mouth bass feed comprises the dendrobium officinale polysaccharide and further comprises crude protein, lysine, crude fat, crude fiber, calcium, total phosphorus and sodium oxide.

[0011] In one of the embodiments, the crude protein content is greater than or equal to 47%, the lysine content is greater than or equal to 2.7%, the crude fat content is greater than or equal to 5.0%, the crude fiber content is less than or equal to 5.0, and the total phosphorus content is 0.5-3.5% in the large-mouth bass feed, in terms of mass percentage.

[0012] In summary, the present application has the following beneficial effects: The present application can promote growth, regulate liver and intestinal health and improve survival rate by adding dendrobium officinale in the feed. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 is the effect of dendrobium officinale polysaccharide on the survival rate of large-mouth bass; Figure 2 is the effect of dendrobium officinale polysaccharide on the liver morphology of large-mouth bass (HE staining 200x); Figure 3 is the effect of dendrobium officinale polysaccharide on the liver digestive enzyme activity of large-mouth bass; Figure 4 is the effect of dendrobium officinale polysaccharide on the intestinal morphology of large-mouth bass (HE staining, A: 100x; B: 200x); Figure 5 is the effect of dendrobium officinale polysaccharide on the intestinal morphology of large-mouth bass after 48 hours of ammonia nitrogen (20mg / L) stress (HE staining, 100x); Figure 6 is the muscle section of large-mouth bass after 48 hours of ammonia nitrogen (20mg / L) stress by adding dendrobium officinale polysaccharide (HE staining, 100x). DETAILED DESCRIPTION

[0014] The present application will be described in detail below in combination with the drawings and examples.

[0015] It should be noted that the orientation words such as "up", "down" and the like involved in the present application are relative to the view angle of the drawings and are merely for the convenience of description and cannot be understood as the limitation on the technical solutions.

[0016] The present application proposes the application of dendrobium officinale polysaccharide as a large-mouth bass feed additive, and the dendrobium officinale polysaccharide is added in the large-mouth bass feed, wherein the content of the dendrobium officinale polysaccharide is less than or equal to 2.5 g in every 1 kg of feed.

[0017] The amount of Dendrobium officinale polysaccharide used in feed has an impact on the breeding effect of largemouth bass. When the amount of Dendrobium officinale polysaccharide is too high, although the weight gain rate of largemouth bass is better, other growth performance indicators decrease and the survival rate also decreases.

[0018] Preferably, the content of Dendrobium officinale polysaccharide in each 1 kg of feed is ≤1 g.

[0019] More preferably, the content of Dendrobium officinale polysaccharides is 0.5 g per 1 kg of feed. At this dosage, the largemouth bass raised using the feed of the present invention exhibit the best performance indicators.

[0020] The method for adding Dendrobium officinale polysaccharides to largemouth bass is as follows: The polysaccharide from Dendrobium officinale was dissolved in water to obtain the additive solution; Add the additive liquid to the base feed, mix well, and then dry to obtain largemouth bass feed.

[0021] Furthermore, the amount of water added is 10% of the total feed mass.

[0022] Furthermore, the drying temperature is 40-50℃, and more preferably, the drying temperature is 55℃.

[0023] The present invention also proposes a feed for largemouth bass, comprising the above-mentioned Dendrobium officinale polysaccharide, as well as crude protein, lysine, crude fat, crude fiber and total phosphorus.

[0024] Preferably, the largemouth bass feed contains, by mass percentage, crude protein ≥ 47%, lysine ≥ 2.7%, crude fat ≥ 5.0%, crude fiber ≤ 5.0%, and total phosphorus 0.5-3.5%.

[0025] The technical solution of the present invention will be described below with reference to specific embodiments.

[0026] Experimental feed preparation: The basic feed used in the experiment was Fenghua brand Qunfeng Opening Treasure Bass Feed No. 3, whose main nutritional components were: crude protein ≥47.0%, lysine ≥2.7%, crude fat ≥5.0%, crude fiber ≤5.0%, and total phosphorus 0.5-3.5%. The content of Dendrobium officinale polysaccharide in the basic feed was 0%. Equal amounts of basic feed were weighed, and Dendrobium officinale polysaccharide was weighed at concentrations of 0 g / kg, 0.1 g / kg, 0.5 g / kg, 2.5 g / kg, and 10 g / kg. The polysaccharide was dissolved in ultrapure water (10% of the feed mass) and then mixed thoroughly into each group of weighed feed. The mixtures were then dried in a 45℃ oven to obtain largemouth bass feed, which was stored in a dry, cool place for later use. Five groups of feeds were obtained.

[0027] Experimental Animals and Culture Experiments: Juvenile largemouth bass were purchased from a largemouth bass hatchery in Huadu District, Guangzhou. After purchase, the fry were temporarily held in a holding tank for one week. 180 largemouth bass with an initial body size of (1.45±0.03 g) were randomly selected and divided into 5 groups. Each group was fed with a pre-prepared diet. Each group had 3 replicates, with 12 fish per replicate. After 28 days of culture, the fish were weighed and sampled for analysis.

[0028] During the breeding period, feed the animals twice a day, at 8:00 am and 4:00 pm, with a water temperature of 23-30℃, a salinity of 30 psu, a pH of 7.8-8.0, ammonia nitrogen content ≤0.05mg / L, dissolved oxygen content ≥6.0mg / L, and nitrite content ≤0.2mg / L.

[0029] Stress experiment: After sampling, 6 fish were left in each tank. A 20 mg / L ammonium chloride solution was prepared for each culture tank and the fish were placed in it for the ammonia nitrogen stress experiment. Samples were taken for analysis after 48 hours.

[0030] The experimental results are as follows: 1. Effects of Dendrobium officinale polysaccharides on the growth performance of largemouth bass The effects of Dendrobium officinale polysaccharide on the growth performance of largemouth bass are shown in Table 1. The weight gain rate and specific growth rate showed a trend of first increasing and then decreasing with the increase of the amount of additive, and reached the maximum value in the third group (addition of 0.5 g / kg Dendrobium officinale polysaccharide) (P<0.05). There were no significant differences in the condition factor, viscera ratio, and liver-to-body ratio among the groups (P>0.05), indicating that an appropriate amount of Dendrobium officinale polysaccharide can promote the growth of largemouth bass.

[0031] Table 1. Effects of Dendrobium officinale polysaccharides on serum growth performance indicators of largemouth bass.

[0032] 2. Effects of Dendrobium officinale polysaccharides on the survival rate of largemouth bass Effects of Dendrobium officinale polysaccharides on liver morphology of largemouth bass, such as Figure 1 As shown, with the increase of Dendrobium officinale polysaccharide addition level, the survival rate of largemouth bass showed a trend of first increasing and then decreasing, reaching a maximum at an addition dose of 0.5 g / kg (P < 0.05). This indicates that adding an appropriate amount of Dendrobium officinale polysaccharide to the feed can improve the survival rate of largemouth bass and increase economic benefits.

[0033] 3. Effects of Dendrobium officinale polysaccharides on liver morphology of largemouth bass Effects of Dendrobium officinale polysaccharides on liver morphology of largemouth bass, such as Figure 2As shown: Under an optical microscope, the hepatocytes in the control group were loosely arranged with large intercellular spaces, slight swelling, and disordered cell structure; the arrangement of hepatocytes in the 0.1g / kg group showed no significant improvement compared to the control group; the hepatocytes in the 0.5g / kg and 2.5g / kg groups were more tightly and neatly arranged with regular cell morphology, clearly visible nuclei, moderate intercellular spaces, clear sinusoidal structure, and normal overall liver tissue structure, showing good tissue morphology; the hepatocytes in the 10g / kg group showed some signs of damage, with abnormal nuclei morphology and shrinkage in some cells.

[0034] 4. Effects of Dendrobium officinale polysaccharides on the activity of digestive enzymes in the liver of largemouth bass Effects of Dendrobium officinale polysaccharides on the activity of liver digestive enzymes in largemouth bass, such as Figure 3 As shown: Trypsin Figure 3 A) The amount of Dendrobium polysaccharide additive gradually increased with increasing dosage, reaching a maximum in the 2.5 g / kg group (P < 0.05); lipase (Lipase) Figure 3 B) The levels showed a trend of first increasing and then decreasing, with the first peak occurring in the 0.5 g / kg group (P < 0.05) and the second peak occurring in the 10 g / kg group (P < 0.05). α-Amylase (α-Amylase) Figure 3 C) It showed a trend of first decreasing and then increasing, reaching the minimum value in the 0.1 g / kg group (P < 0.05), and then gradually increasing, reaching the maximum value in the 10 g / kg group (P < 0.05).

[0035] 5. Effects of Dendrobium officinale polysaccharides on intestinal morphology of largemouth bass Effects of Dendrobium officinale polysaccharides on liver morphology of largemouth bass, such as Figure 4 As shown: In the control group, the intestinal villi were loosely arranged, with relatively low villi height, low goblet cell density, and large intervillous spaces. In the 0.1 g / kg group, intestinal villi height began to increase, villi arrangement became more compact, the number of goblet cells slightly increased, and mucosal thickness improved. In the 0.5-2.5 g / kg group, intestinal villi height significantly increased, villi morphology became more regular and uniform, goblet cells were evenly distributed and significantly increased in number, and the lamina propria structure became denser. In the 10 g / kg group, villi height decreased significantly, and intervillous spaces increased.

[0036] 6. Effects of Dendrobium officinale polysaccharides on intestinal morphology of largemouth bass under ammonia nitrogen stress Effects of Dendrobium officinale polysaccharides on intestinal morphology of largemouth bass under ammonia nitrogen stress, such as Figure 5As shown: CON represents the non-stress group, with normal intestinal villus morphology; in the group with 0 g / kg of Dendrobium officinale polysaccharide, the intestinal villus was significantly shorter, the intervillous space was larger, and the villus was severely damaged. As the level of Dendrobium officinale polysaccharide added increased, the villus length and the number of goblet cells gradually increased, but more is not necessarily better. The optimal state was reached in the 0.5 g / kg group. Subsequent increases in the amount of additive caused damage to the intestinal villus.

[0037] 7. Effects of Dendrobium officinale polysaccharides on muscle morphology of largemouth bass under ammonia stress Effects of Dendrobium officinale polysaccharides on the cross-sectional morphology of largemouth bass muscle under ammonia nitrogen stress, such as Figure 6 As shown in the figure, the CON group was the non-stress group, and the cross-section of the muscle fibers showed that the muscle fibers were arranged in an orderly manner; the gaps between the muscle fibers in the group with 0 g / kg Dendrobium officinale polysaccharide were significantly widened, and the muscle fiber arrangement gradually became more orderly with the addition of Dendrobium officinale polysaccharide.

[0038] The experimental results show that the optimal effect is achieved when the amount of Dendrobium officinale polysaccharide added to the feed is 0.5 g / kg.

[0039] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. The application of Dendrobium officinale polysaccharide as a feed additive for largemouth bass, characterized in that, Dendrobium officinale polysaccharide was added to the feed for largemouth bass, wherein the content of Dendrobium officinale polysaccharide in each 1 kg of feed is ≤2.5 g.

2. The application of Dendrobium officinale polysaccharide as described in claim 1 as a feed additive for largemouth bass, characterized in that, The content of Dendrobium officinale polysaccharides in every 1 kg of feed is ≤1 g.

3. The application of Dendrobium officinale polysaccharide as described in claim 2 as a feed additive for largemouth bass, characterized in that, The content of Dendrobium officinale polysaccharides in each 1 kg of feed is 0.5 g.

4. The application of Dendrobium officinale polysaccharide as described in claim 1 as a feed additive for largemouth bass, characterized in that, The method for adding Dendrobium officinale polysaccharides to largemouth bass is as follows: The polysaccharide from Dendrobium officinale was dissolved in water to obtain the additive solution; Add the additive liquid to the base feed, mix well, and then dry to obtain largemouth bass feed.

5. The application of Dendrobium officinale polysaccharide as described in claim 4 as a feed additive for largemouth bass, characterized in that, The amount of water added is 10% of the total feed mass.

6. The application of Dendrobium officinale polysaccharide as described in claim 4 as a feed additive for largemouth bass, characterized in that, The drying temperature is 40-50℃.

7. A feed for largemouth bass, characterized in that, The application as described in any one of claims 1-6 involves adding Dendrobium officinale polysaccharides to the basal feed; Largemouth bass feed also includes crude protein, lysine, crude fat, crude fiber, calcium, total phosphorus, and sodium oxide.

8. The largemouth bass feed as described in claim 7, characterized in that, Based on mass percentage, the crude protein content of largemouth bass feed is ≥47%, lysine content is ≥2.7%, crude fat content is ≥5.0%, crude fiber content is ≤5.0%, and total phosphorus content is 0.5-3.5%.

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