Feed additive for improving hair follicle density for rex rabbits and use method thereof

Abstract

The present invention discloses a feed additive for improving hair follicle density for Rex rabbits and a method of using the additive. The ingredients and dosage of the additive are: vitamin B5: 30-90 mg / kg; methionine 2-3 g / kg; zinc sulfate 50-90 mg / kg. The method of using the feed additive for improving hair follicle density for Rex rabbits is as follows: after the first age-related molting of Rex rabbits at the age of 3 months, the feed additive for improving hair follicle density for Rex rabbits is added, and the rabbits are raised until they are five months old and slaughtered. The feed additive for improving hair follicle density for Rex rabbits of the present invention is simple to make, the raw materials are cheap and easy to obtain, it is green, environmentally friendly and safe, and it has a good effect on improving hair density and skin quality when applied to Rex rabbit production.

Description

Technical Field

[0001] The invention belongs to the technical field of feed additives, and particularly relates to a feed additive for improving hair follicle density for rex rabbits and a use method thereof. Background Art

[0002] Rex rabbits, also known as Rex rabbits, are herbivorous mammals that grow both skin and meat. Rex rabbit skin is the main product of Rex rabbits and has important economic value. Rex rabbit skin is beautiful, light, soft, and has good thermal insulation performance. It has the characteristics of "short, fine, dense, flat, beautiful, and firm". The main indicators for evaluating the quality of skins include coat density, skin area, skin weight, skin thickness, coat length, coat color, and skin tensile strength. Among them, coat density is the most important indicator for measuring the quality of Rex rabbit skins. Coat density directly affects the grade of fur, and then affects the price. With the development of Rex rabbit breeding, Rex rabbit breeding has gradually become intensive and large-scale production. How to further improve the quality of Rex rabbit skins under the background of intensive and large-scale production is an urgent problem to be solved in production.

[0003] Hair follicles (HF) are important accessory organs of mammalian skin, which control the growth of hair. Improving the level of hair follicle development can increase hair density. Hair density is the most important indicator for measuring fur quality, which affects the grade and price of fur. The growth and development of hair follicles are controlled by many factors, such as nutritional status, age, season, and breed genetics. The physiological state of hair follicles can be roughly divided into three periods: growth phase, decline phase, and resting phase. During the resting phase, hair follicles are stimulated by certain signal molecules and enter the next growth phase. It is a complex and precise process. Hair follicles can regenerate periodically and are highly controllable. Its growth and development are controlled by a series of growth promoting factors and inhibitory factors. Improving the level of hair follicle development is an important way to increase hair density, and it is also a problem that researchers have been committed to studying. Hair follicle development is greatly affected by the environment, hormones, and animal nutrition. Therefore, starting with animal diet additives is a relatively easy and low-cost means to improve the level of hair follicle development in Rex rabbits.

[0004] Vitamin B5, also known as pantothenic acid, is a B vitamin necessary for animal growth. Pantothenic acid is a component of coenzyme A (CoA) and acyl carrier protein (ACP). It plays a role in transferring and activating acyl and acetyl groups and is essential for a variety of acetylation reactions in the metabolism of carbohydrates, fatty acids and nitrogen compounds. Studies on mice, chickens, raccoon dogs and other animals have shown that pantothenic acid deficiency can lead to hair color changes, hair loss and skin defects. Methionine is not only an essential amino acid but also the first limiting amino acid for wool-producing animals. As a sulfur-containing amino acid, it plays an important role in wool production performance and wool quality. Zinc is one of the trace elements necessary for animal growth. It is a component of many enzymes in the body, participates in the metabolism of proteins, sugars and lipids, and is related to animal reproduction, immunity and growth and development. Zinc plays a very important role in improving animal growth performance, fur quality and carcass quality. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a feed additive for improving hair density and hide quality of Rex rabbits. The feed additive is simple to prepare, the raw materials are cheap and readily available, and the feed additive is green, environmentally friendly and safe. The feed additive can improve hides and skins in Rex rabbit production.

[0006] The objective of the present invention is achieved by adopting the following technical scheme: a feed additive for improving hair follicle density of Rex rabbits, the ingredients and dosage of the additive are: vitamin B5: 30-90 mg / kg; methionine 2-3 g / kg; zinc sulfate 50-90 mg / kg.

[0007] Preferably, the ingredients and dosages of the additives are: vitamin B5: 90 mg / kg; methionine 3 g / kg; zinc sulfate 60 mg / kg.

[0008] Preferably, the ingredients and dosages of the additives are: vitamin B5: 90 mg / kg; methionine 3 g / kg; zinc sulfate 90 mg / kg.

[0009] Preferably, the ingredients and dosages of the additives are: vitamin B5: 70 mg / kg; methionine 3 g / kg; zinc sulfate 60 mg / kg.

[0010] The method for using the feed additive for increasing hair follicle density of Rex rabbits is as follows: after the first age-related molting of Rex rabbits at the age of 3 months, the feed additive for increasing hair follicle density of Rex rabbits is added, and the rabbits are raised until they are five months old and slaughtered.

[0011] Beneficial effects:

[0012] (1) Experiments have shown that the combined additives have a significant effect on improving the hair follicle density and hide quality of Rex rabbits;

[0013] (2) The raw materials of this additive are relatively cheap and easy to obtain, and the overall cost is low;

[0014] (3) The additive combination is safe, environmentally friendly, and has no side effects on Rex rabbits;

[0015] (4) The preparation method of the additive combination is relatively simple and easy to implement at the production site. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The following is further described in detail with reference to the accompanying drawings and specific embodiments:

[0017] Figure 1 The effect of different feed additives on the hair follicle density of Rex rabbits.

[0018] Figure 2 This is a micrograph showing the effects of different feed additives on the hair follicle density of Rex rabbits.

[0019] Figure 3 The effect of different feed additives on the diameter of Rex rabbit hair follicles.

[0020] Figure 4 The effect of different feed additives on the skin area of ​​Rex rabbits.

[0021] Figure 5 The effect of different feed additives on the hair length of Rex rabbits.

[0022] Figure 6 The effect of different feed additives on the skin thickness of Rex rabbits.

[0023] Figure 7 The effect of different feed additives on the shrinkage temperature of Rex rabbit skin.

[0024] Figure 8 The effect of different feed additives on the tensile strength of Rex rabbit skin.

[0025] Fig. 9 The effect of different feed additives on the elongation under specified load of Rex rabbit skin.

[0026] Fig.10 The effect of different feed additives on the elongation at break of Rex rabbit skin.

[0027] Fig.11 The effect of different feed additives on the diameter of Rex rabbit hair.

[0028] Fig.12 The effect of additives in different formula proportions on the hair follicle density of Rex rabbits.

[0029] Fig.13 The effect of additives in different formula proportions on the diameter of Rex rabbit hair follicles.

[0030] Fig.14 The effect of additives in different formula proportions on the diameter of Rex rabbit hair.

[0031] Fig.15 The effect of additives with different formula proportions on the skin area of ​​Rex rabbits.

[0032] Fig.16 The effect of additives in different formula proportions on the shrinkage temperature of Rex rabbit skin.

[0033] Fig.17 The effect of additives in different formula proportions on the elongation of Rex rabbit skin at specified load.

[0034] Fig.18 The effect of additives in different formula proportions on the elongation at break of Rex rabbit skin.

[0035] Fig.19 The effect of additives in different formula proportions on the length of Rex rabbit hair.

[0036] Fig. 20 The effect of different formula proportions of additives on the thickness of Rex rabbit skin.

[0037] Fig.21 The effect of additives in different formula proportions on the shrinkage temperature of Rex rabbit skin. DETAILED DESCRIPTION

[0038] The invention discloses a feed additive, which is composed of vitamin B5, methionine and zinc sulfate. Through experiments, it is found that the feed additive can effectively increase the density of secondary hair follicles of Rex rabbits, reduce the hair fineness of Rex rabbits, increase the skin area, increase the tensile strength and load elongation of the skin, and improve the overall quality of Rex rabbit skins.

[0039] Example 1

[0040] After the first molting of Rex rabbits at the age of 3 months, add a combination of additives. The ingredients and dosage of the additives are: vitamin B5: 90mg / kg; methionine 3g / kg; zinc sulfate 60mg / kg. Raise them until they are slaughtered at the age of 5 months, and the fur density of the Rex rabbits will be significantly improved.

[0041] Example 2

[0042] After the first molting of Rex rabbits at the age of 3 months, add a combination of additives. The ingredients and dosage of the additives are: vitamin B5: 70mg / kg; methionine 3g / kg; zinc sulfate 60mg / kg. Raise them until they are slaughtered at the age of 5 months, and the fur density of the Rex rabbits will be significantly improved.

[0043] Example 3

[0044] After the first molting of Rex rabbits at 3 months of age, add a combination of additives. The ingredients and dosage of the additives are: vitamin B5: 90mg / kg; methionine 3g / kg; zinc sulfate 90mg / kg. Raise until slaughter, and the fur density of Rex rabbits will be significantly improved.

[0045] Experimental Example 1

[0046] (1) Experimental design

[0047] The experiment selected 300 white 3-month-old Rex rabbits of similar age and randomly divided them into 5 groups, 60 in each group. Group A was fed a basic diet, which was prepared according to the US NRC standard. Group B added 70 mg / kg of vitamin B5 (also known as pantothenic acid) to the diet; Group C added 3 g / kg of methionine; Group D added 60 mg / kg of zinc sulfate; Group E added vitamin B5 + methionine + zinc sulfate (vitamin B5: 70 mg / kg; methionine 3 g / kg; zinc sulfate 60 mg / kg). The experimental period was 90 days. All Rex rabbits were raised in three-dimensional single cages, with a dedicated person responsible for management. They were fed once in the morning, noon and evening every day, and had free access to food and water.

[0048] (2) Methods for determining hair follicle density and fur quality

[0049] After 90 days of feeding under the same conditions, skin samples were taken for HE staining to determine the hair follicle density and hair follicle diameter.

[0050] Fur quality measurement methods: including fur length, skin area, capillary fineness, fur thickness, tensile strength, etc.

[0051] The specific determination method is as follows:

[0052] 1) Slaughter and sampling of Rex rabbits

[0053] The rabbits were slaughtered by neck displacement method and skinned immediately after slaughter. Eight rabbit skins were randomly selected from each group and treated with salting. After skinning, a square skin block with a side length of 2 cm was taken from the cross of the buttocks of other Rex rabbits, the hair was cut off, and the skin was immediately fixed in a paraformaldehyde solution after being rinsed with physiological saline.

[0054] 2) Preparation of skin sample tissue sections and determination of hair follicle development-related data

[0055] ① Dehydration: Skin tissue samples were dehydrated with alcohol gradient, the specific steps were: 75% ethanol (1h) → 85% ethanol (1h) → 95% ethanol I (1h) → 95% ethanol II (1h) → 100% ethanol I (45min) → 100% ethanol II (45min) → phenylethanol (45min). The phenylethanol solution was xylene and ethanol in a volume ratio of 1:1.

[0056] ② Transparency and embedding: The skin tissue was transparentized with xylene and then fixed with paraffin. The steps were: xylene I (7 min) → xylene II (7 min) → benzene wax (1 h) → paraffin I (1 h) → paraffin II (1 h).

[0057] ③ Sectioning: Section after paraffin embedding for 48 hours. Place the wax block on the slicer. Press the leveling button to adjust the distance between the blade and the wax block. Adjust the slicer gear to 10μm for trial cutting. When cutting skin tissue, adjust to 6μm for formal sectioning.

[0058] ④ Spreading and baking slices: Gently place the cut tissue into a slice spreader (45°C). After the skin tissue is completely flattened, use a glass slide to scoop out the tissue, remove the remaining water, and place it on a slice dryer to dry.

[0059] ⑤Hemotoxylin and eosin staining (HE) staining: Use xylene to dissolve the paraffin on the slices, twice, each time for 15 minutes. Then rehydrate the dewaxed slices with ethanol solutions of different concentrations, the rehydration steps are: 100% ethanol I (5min) → 100% ethanol II (5min) → 80% ethanol (5min) → distilled water (2min). Stain with hematoxylin for 1-2min, wash and differentiate with hydrochloric acid differentiation solution, the differentiation time is 30s, rinse with tap water to terminate the differentiation. Place the slices in 0.5% eosin solution for restaining, and then dehydrate, the steps are: 80% ethanol (10s) → 95% ethanol I (2min) → 95% ethanol II (2min) → 100% ethanol I (2min) → 100% ethanol II (2min). Finally, use xylene to make it transparent, divided into two steps, each step is 5min.

[0060] ⑥ Sealing: After taking out from xylene, wipe off the liquid around the slide tissue with filter paper, cover with a coverslip, and quickly seal with gum.

[0061] ⑦ Determination of hair follicle-related data: Each slice was photographed 7 times under a 40x microscope, and each slice was observed using the MoticImages Plus 2.0 system, and the number of primary and secondary hair follicles was counted in each field of view.

[0062] 3) Hide quality measurement

[0063] The salted hides were sent to Lanzhou Jihua 3512 Leather Factory for tanning using the industrial nitrate method and then tested. The indicators and methods for determining hide quality are as follows:

[0064] ① Hide area: measure the length from the middle of the neck to the base of the tail, and measure the length from this line to the 1 / 2 of the edge of the skin board, and take the average value as the basic length unit; measure the width under the shoulder, waist and buttocks, and the average value is the basic width unit; length × width is the hide area.

[0065] ② Rabbit hair diameter: Samples were taken from the shoulders, back and buttocks. Ten hair clumps were taken from each hair sample. Glycerin sections were made for each hair. The sections were projected on a fiber fineness projector at 400 times magnification. The diameter was measured with a wedge ruler and the average value was calculated.

[0066] ③ Hair length: Take samples from the shoulders, back and buttocks. Take 10 hair clumps for each hair sample and measure the natural length with a ruler. The average value is taken as the hair sample length.

[0067] ④ Fur thickness: Use a caliper to measure the double-layer thickness at the cross position or take the average value of 5-point sampling.

[0068] ⑤Tensile strength: in accordance with the national standard "Determination of tensile strength of finished fur products" (GB / T1269-1991).

[0069] ⑥ Specified elongation under load: The operation shall be carried out in accordance with the national standard "Determination of elongation under load of finished fur products" (GB / T1270-1991).

[0070] ⑦ Shrinkage temperature: The operation shall be carried out in accordance with the national standard "Determination of shrinkage temperature of leather" (GB / T4689.8-1984).

[0071] ⑧ Elongation at break: The operation shall be carried out in accordance with the national standard "Determination of elongation at break of finished fur products" (GB / T60005-1991).

[0072] (3) Test results

[0073] 1) Differences in hair follicle-related indicators of Rex rabbits with different feed additives

[0074] Depend on Figure 1 to Figure 3 It can be seen that the number of primary and secondary hair follicles of Rex rabbits in the combined additive group was significantly higher than that in the control group and the single feed additive group; the diameter of primary and secondary hair follicles was significantly lower than that in the control group and the single additive group.

[0075] 2) Effects of different feed additives on the quality of Rex rabbit skins

[0076] Depend on Figure 4 It can be seen that the skin area of ​​the Rex rabbits in the group supplemented with combined feed additives was the largest, significantly higher than that of the control group.

[0077] 3) By Figure 5 , Figure 6 , Figure 7 It can be seen that different additives have no significant effect on the length of Rex rabbit hair, thickness of skin and shrinkage temperature of skin.

[0078] 4) By Figure 8 It can be seen that adding the combined additive group and methionine group to the feed significantly improved the tensile strength of Rex rabbit skin (P<0.05).

[0079] 5) By Figures 9 to 11 It can be seen that the elongation at specified load of the Rex rabbit skin in the group with vitamin B5, methionine and combined additives in feed was significantly higher than that in the control group. There was no significant difference in the elongation at break of the Rex rabbit skin among the five groups. The diameter of the Rex rabbit hair follicles in the group with methionine and combined additives was significantly lower than that in the control group.

[0080] Experimental Example 2

[0081] The results of Experimental Example 1 show that the effect of combined additives is better than that of single additives, but the results cannot fully explain the optimal dosage ratio of the additives. This experiment added additives of different ratios to Rex rabbits and measured the fur quality after 60 days of feeding.

[0082] Test method:

[0083] The experiment selected 300 white 3-month-old Rex rabbits of similar age and randomly divided them into 6 groups, 50 in each group. Different additive ratios were used. Group E1 added vitamin B5: 70mg / kg, methionine 3g / kg, and zinc sulfate 60mg / kg to the basic diet; Group E2 added vitamin B5: 30mg / kg, methionine 3g / kg, and zinc sulfate 60mg / kg to the basic diet; Group E3 added vitamin B5: 70mg / kg, methionine 2g / kg, and zinc sulfate 60mg / kg to the basic diet; Group E4 added vitamin B5: 70mg / kg, methionine 3g / kg, and zinc sulfate 50mg / kg to the basic diet; Group E5 added vitamin B5: 90mg / kg, methionine 3g / kg, and zinc sulfate 90mg / kg to the basic diet. The E6 group's basic diet was supplemented with vitamin B5: 90 mg / kg; methionine 3 g / kg; zinc sulfate 60 mg / kg; (the added amounts were in compliance with the provisions of the "Regulations on the Administration of Feed and Feed Additives" promulgated by the state).

[0084] The animals were raised to 6 months of age and then slaughtered. The hair follicle density, hair follicle diameter, hair length, skin area, capillary fineness, fur thickness, tensile strength and other indicators were measured according to the method described in Experimental Example 1 to determine the fur quality.

[0085] Test results:

[0086] Depend on Fig.12 It can be seen that the primary and secondary hair follicle densities of Rex rabbits in groups E5 and E6 were significantly higher than those in other groups, indicating that the additive formulas of these two groups have a greater effect on improving the hair density of Rex rabbits.

[0087] Depend on Fig.13 It can be seen that the diameter of hair follicles in group E6 is the smallest, and the diameters of primary and secondary hair follicles are significantly lower than those in groups E2, E3, and E4; the diameter of primary hair follicles in group E5 is larger than that in group E6, and the diameter of secondary hair follicles is no different from that in group E6. Fig.14 It can be seen that the diameter of the Rex rabbit hair in the E6 group is the smallest, which means that the combination of additives according to the E6 formula can significantly reduce the fineness of Rex rabbit hair.

[0088] Depend on Fig.15 It can be seen that the skin area of ​​groups E3, E5 and E6 is the best, significantly larger than that of other groups, which indicates that the additives of these three groups can promote the growth of Rex rabbits and increase the skin area.

[0089] Depend on Figure 16 to Figure 21 It can be seen that there are no significant differences in the tensile strength, shrinkage temperature, elongation at break, elongation under load, hide thickness and average hair length of Rex rabbit hides among the groups with different formula addition ratios, indicating that changes in the formula within a certain range have no significant effect on the quality of the leather.

[0090] Combining the above indicators, the E6 group (basic diet supplemented with vitamin B5: 90mg / kg; methionine 3g / kg; zinc sulfate 60mg / kg) had relatively excellent effects in increasing hair density, reducing capillary fineness and increasing hide area.

[0091] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A feed additive for increasing hair follicle density for Rex rabbits, characterized in that: The ingredients and dosages of the additives are: vitamin B5: 90 mg / kg basic diet; methionine: 3 g / kg basic diet; zinc sulfate: 60 mg / kg basic diet.

2. A feed additive for increasing hair follicle density for Rex rabbits, characterized in that: The ingredients and dosages of the additives are: vitamin B5: 90 mg / kg basic diet; methionine: 3 g / kg basic diet; zinc sulfate: 90 mg / kg basic diet.

3. A method for using a feed additive for increasing hair follicle density in Rex rabbits, characterized in that: After the first molting of Rex rabbits at the age of 3 months is completed, the feed additive for increasing hair follicle density of Rex rabbits according to claim 1 or 2 is added, and the rabbits are raised until they are five months old and then slaughtered.

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