Kluyveromyces marxianus YZC-01 solid preparation for improving delicate flavor of mutton and application thereof

Abstract

The invention relates to a Kluyveromyces marxianus YZC-01 solid preparation for improving the delicate flavor of mutton, which contains living cells of a Kluyveromyces marxianus YZC-01 strain, and the colony forming unit (CFU) of the Kluyveromyces marxianus YZC-01 solid preparation is 1.0 * 10 < 8 > / g to 10.0 * 10 < 8 > / g. The invention further relates to application of the kluyveromyces marxianus YZC-01 solid preparation in improvement of the delicate flavor of mutton, and results show that by adding 0.01 wt%-1.0 wt% of the kluyveromyces marxianus solid preparation into sheep feed and / or drinking water, the growth rate of sheep can be increased by 3.0%-9.8%, the flavor nucleotides in the mutton can be increased by 1.29%-2.81%, and the flavor of the mutton can be increased by 1.29%-2.81%. The Kluyveromyces marxianus YZC-01 solid preparation disclosed by the invention has the advantages that the content of flavor amino acid in mutton is increased by 7.6%-28.0%, and the Kluyveromyces marxianus YZC-01 solid preparation has an important application prospect.

Description

Technical Field

[0001] The invention belongs to the field of biotechnology and relates to a Kluyveromyces marxianus YZC-01 solid preparation for improving the umami taste of mutton and an application thereof. Background Art

[0002] Kluyveromyces marxianus is a eukaryotic microorganism that not only grows rapidly, has high heat resistance, a broad substrate spectrum, and produces many types of enzymes, but is also rich in antiviral substances such as glucan. It was approved as a new food ingredient in 2013 and is also an edible yeast for humans approved in my country's edible probiotic catalog.

[0003] In the aspect of breeding, Kluyveromyces marxianus can improve the production performance and immunity of livestock and poultry, and can also improve the palatability and utilization rate of feed by fermenting feed. Studies have found that Kluyveromyces marxianus can improve the growth rate and immunity of sheep, but there is no literature report on using Kluyveromyces marxianus to improve the umami taste of mutton.

[0004] In recent years, the scale of mutton farming in my country has shown an increasing trend, and the main breeding variety is the small-tailed Han sheep. In 2023, China's mutton production will be 5.31 million tons, an increase of 1.3%. Mutton has a high protein content, low fat and cholesterol content, and is rich in many essential amino acids and other important minerals and trace elements for the human body. It is easily absorbed by the human body and has always played an important role in my country's dietary structure. With the improvement of people's living standards, the demand for mutton in my country has exceeded the output, and the demand gap mainly comes from imports. Although large-scale farming has improved the production efficiency of mutton, the widespread use of antibiotics such as chlortetracycline has posed a serious threat to the food safety of mutton. With the improvement of people's living standards and the enhancement of food safety awareness, consumers have put forward higher requirements for the quality and flavor of mutton. Therefore, it is urgent to research and develop a preparation that can safely and effectively improve the flavor of mutton. Summary of the invention

[0005] One of the objectives of the present invention is to provide a solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton. The solid preparation contains living cells of Kluyveromyces marxianus YZC-01 strain, and when used in sheep feed or drinking water and then fed to sheep, the content of flavor nucleotides and flavor amino acids in mutton can be significantly increased, thereby improving the umami taste of mutton.

[0006] The second objective of the present invention is to provide an application of the above-mentioned Kluyveromyces marxianus YZC-01 solid preparation in improving the umami taste of mutton.

[0007] To this end, the first aspect of the present invention provides a solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton, which contains living cells of Kluyveromyces marxianus YZC-01 strain.

[0008] According to the present invention, the solid preparation of Kluyveromyces marxianus YZC-01 is a solid bacterial powder of Kluyveromyces marxianus YZC-01 obtained by fermenting and culturing the Kluyveromyces marxianus YZC-01 strain, harvesting cells by centrifugation, freeze-drying, crushing and passing through a 100-mesh sieve.

[0009] In the present invention, the deposit number of the Kluyveromyces marxianus YZC-01 strain is CGMCC NO.29514.

[0010] In some embodiments of the present invention, in the solid bacterial powder of Kluyveromyces marxianus YZC-01, the colony forming unit (CFU) of Kluyveromyces marxianus YZC-01 strain is 1.0×10 8 / g to 10.0×10 8 / g.

[0011] In some embodiments of the present invention, the moisture content of the solid powder of Kluyveromyces marxianus YZC-01 is less than 8 wt %.

[0012] According to the present invention, the solid preparation can increase the content of flavor nucleotides in mutton after being fed to sheep.

[0013] In some embodiments of the present invention, the solid preparation can increase the content of flavor nucleotides in mutton by 1.29wt%-2.81wt% after being fed to sheep.

[0014] In the present invention, the flavor nucleotide is inosine nucleotide.

[0015] According to the present invention, the solid preparation can increase the content of flavor amino acids in mutton after being fed to sheep.

[0016] In some embodiments of the present invention, the solid preparation can increase the content of flavor amino acids in mutton by 7.6wt%-28.0wt% after being fed to sheep.

[0017] In the present invention, the flavor amino acids include one or more of glutamic acid, serine, glycine, isoleucine, leucine, alanine and proline.

[0018] The second aspect of the present invention provides the use of the solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton as described in the first aspect of the present invention in improving the umami taste of mutton.

[0019] According to the present invention, the application comprises adding the solid preparation to the sheep's feed and / or drinking water, stirring the mixture evenly and then feeding the mixture to the sheep.

[0020] In some embodiments of the present invention, the amount of the solid preparation added to the sheep feed and / or the sheep drinking water is 0.01wt% to 1.0wt%, preferably 0.1wt% to 1.0wt%, and more preferably 1.0wt%, based on the total weight of the sheep feed and / or the sheep drinking water.

[0021] In the present invention, the feed comprises one or more of granules, powders, semisolids and liquid feeds.

[0022] In the present invention, the sheep include one or more of small-tail Han sheep, large-tail Han sheep, Northeast fine-wool sheep, Hu sheep, Tan sheep, Mongolian sheep, Dorper sheep and black goat.

[0023] The present invention provides a solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton, which contains living cells of Kluyveromyces marxianus YZC-01 strain. Because Kluyveromyces marxianus can produce multiple enzymes such as protease and cellulase, it can help sheep digest and absorb feed. In addition, Kluyveromyces marxianus is rich in polysaccharides such as glutathione, glucan and casein, which can improve the immune function of sheep. Therefore, by adding Kluyveromyces marxianus to feed, not only the growth rate and disease resistance of sheep are significantly improved, but more importantly, the content of flavor nucleotides and flavor amino acids can be increased, so that the umami taste of mutton is greatly improved, which has important and broad application prospects.

[0024] Strain preservation

[0025] Kluyveromyces marxianus was isolated and identified by Beijing Beike Yiran Biotechnology Co., Ltd. and has been deposited in the General Microbiological Center of China Microbiological Culture Collection Committee (referred to as: CGMCC; address: Institute of Microbiology, Chinese Academy of Sciences, No. 3, Yard 1, Beichen West Road, Chaoyang District, Beijing), deposit date: January 4, 2024, deposit number: CGMCC No. 29514. In the present invention, the strain is named Kluyveromyces marxianus strain YZC-01, also known as Kluyveromyces marxianus YZC-01. DETAILED DESCRIPTION

[0026] To make the present invention easy to understand, the present invention will be described in detail below. However, before describing the present invention in detail, it should be understood that the present invention is not limited to the specific embodiments described. It should also be understood that the terms used herein are only for describing specific embodiments and are not intended to be limiting.

[0027] Unless otherwise defined, all terms used herein have the same meaning as commonly understood by those of ordinary skill in the art to which the invention belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present invention, preferred methods and materials are now described.

[0028] I. Terminology

[0029] The term "solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton" mentioned in the present invention refers to a solid preparation containing living cells of Kluyveromyces marxianus YZC-01, which has the effect of increasing the content of flavor nucleotides and flavor amino acids in mutton after being fed to sheep.

[0030] II. Implementation Plan

[0031] As mentioned above, sheep farming in my country has always been highly pursuing output and meat production efficiency. Although large-scale breeding technology has shortened the growth cycle of sheep and greatly improved the production efficiency of mutton, the quality and flavor of mutton have continued to decline. In recent years, with the improvement of people's living standards and the enhancement of food safety awareness, how to improve the quality and flavor of mutton has become a basic research and application problem that scholars at home and abroad urgently need to solve. In response to the above problems, the inventors have conducted a lot of research on the flavor components of mutton and methods for improving the flavor of mutton.

[0032] First, the inventors have analyzed and studied the flavoring components of mutton. Mutton mainly includes water, nucleotides, proteins, amino acids, carbohydrates and lipids. The taste mainly comes from the flavoring substances in the meat, such as nucleotides, amino acids, polypeptides, acids and carbohydrates. These substances are sensed by the taste buds on the tongue and transmitted to the brain through nerves, thereby presenting sweet, salty, sour, bitter and fresh tastes. The strength of the umami taste is mainly determined by the content of flavoring nucleotides and flavoring amino acids in the meat. Studies have found that flavoring nucleotides are mainly composed of inosine nucleotides (inosinic acid, Inosine 5-monophosphate, IMP), guanosine nucleotides (guanosine monophosphate, GMP) and adenine nucleotides (Adenosine monophosphate, AMP), and flavoring amino acids mainly include glutamic acid, serine, glycine, isoleucine, leucine, alanine and proline. Therefore, the increase in the content of flavoring nucleotides and flavoring amino acids in mutton can improve the degree of umami taste of mutton.

[0033] Then, the inventors fed sheep with different amounts of Kluyveromyces marxianus in feed and studied the changes in the content of flavor nucleotides and flavor amino acids that reflect the umami taste in mutton. It was found that the content of flavor nucleotides and flavor amino acids in mutton could be significantly increased after feeding Kluyveromyces marxianus YZC-01.

[0034] Furthermore, the inventors have found through research that Kluyveromyces marxianus has a high protein content, high production of antiviral substances and growth factors, and its cell wall contains polysaccharides such as casein, which has extremely high nutritional value and the function of improving animal immunity. Through a series of studies on the optimization and control of culture medium and culture conditions, the inventors have finally obtained the technology of high-density fermentation and cultivation of Kluyveromyces marxianus.

[0035] The inventors further discovered that if the solid preparation of Kluyveromyces marxianus YZC-01 is directly added to the feed in a certain proportion and fed to sheep, not only the growth rate and disease resistance of the sheep are improved, but more importantly, the content of xanthine nucleotides and flavor amino acids that reflect the umami taste in mutton is greatly increased.

[0036] Therefore, the solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton according to the first aspect of the present invention contains living cells of Kluyveromyces marxianus.

[0037] In an embodiment of the present invention, the deposit number of the Kluyveromyces marxianus YZC-01 is CGMCC NO.29514, and the deposit date is January 4, 2024.

[0038] Kluyveromyces marxianus is a yeast that can be eaten directly by humans and has been widely used. Because Kluyveromyces marxianus is a probiotic that produces high levels of antiviral substances and growth factors, its cell wall is rich in polysaccharides, has extremely high nutritional value, and can improve animal immunity. Feeding sheep can not only increase the growth rate and disease resistance of sheep, but more importantly, adding Kluyveromyces marxianus can promote the metabolism of sheep, greatly increase the content of flavor nucleotides and flavor amino acids in mutton, and greatly enhance the umami taste of mutton.

[0039] For example, in some embodiments of the present invention, the solid preparation can increase the growth rate of sheep by 3.0%-9.8% after being fed to sheep.

[0040] For another example, in some embodiments of the present invention, the solid preparation can increase the content of flavor nucleotides in mutton by 1.29wt%-2.81wt% after being fed to sheep.

[0041] In the present invention, the flavor nucleotide is inosine nucleotide.

[0042] For another example, in some embodiments of the present invention, the solid preparation can increase the flavor amino acid content in mutton by 7.6wt%-28.0wt% after being fed to sheep.

[0043] In the present invention, the flavor amino acid includes one or more of glutamic acid, serine, glycine, isoleucine, leucine, alanine and proline.

[0044] According to the present invention, the solid preparation of Kluyveromyces marxianus for improving the umami taste of mutton is a solid bacterial powder (with a moisture content of less than 8%) obtained by liquid fermentation, centrifugal cell harvesting, freeze drying, crushing and passing through a 100-mesh sieve of Kluyveromyces marxianus; the colony forming unit (CFU) of Kluyveromyces marxianus is 1.0×10 8 / g to 10.0×10 8 / g.

[0045] In some embodiments of the present invention, the preparation method of the Kluyveromyces marxianus solid preparation for improving the umami taste of mutton is as follows:

[0046] The Kluyveromyces marxianus was fermented in a liquid culture medium at 30-35°C for 3-5 days. The colony forming units of Kluyveromyces marxianus in the culture were 1.0×10 6 / mL and 1.0×10 7 / mL. The cells were harvested by centrifugation, freeze-dried, crushed and passed through a 100-mesh sieve to obtain a solid bacterial powder (water content less than 8%); the colony forming unit (CFU) of Kluyveromyces marxianus was 1.0×10 8 / g to 10.0×10 8 / g.

[0047] There is no particular limitation on the growth medium of Kluyveromyces marxianus in the present invention, as long as it can culture Kluyveromyces marxianus. Preferably, the growth medium of Kluyveromyces marxianus YZC-01 is composed of (per liter of water): 10.0 g beef extract, 10.0 g peptone, 10.0 g yeast powder, 5.0 g NaCl, 10.0 g glucose, and 1000 ml water.

[0048] The use of the solid preparation of Kluyveromyces marxianus for improving the umami taste of mutton as described in the first aspect of the present invention in the second aspect of the present invention can be understood as a method for improving the umami taste of mutton using the solid preparation of Kluyveromyces marxianus of the present invention, which comprises adding the solid preparation to the feed and / or drinking water of the sheep, stirring evenly and then feeding the sheep, thereby increasing the content of flavor nucleotides and flavor amino acids in the mutton and improving the umami taste of the mutton.

[0049] In some specific embodiments of the present invention, based on the total weight of the sheep feed and / or the sheep drinking water, 0.01wt% to 1.0wt%, preferably 0.1wt% to 1.0wt%, and further preferably 1.0wt% of the above-mentioned Kluyveromyces marxianus solid preparation of the present invention is added to the sheep feed and / or the sheep drinking water, and the mixture is evenly stirred and then fed to sheep, which can significantly increase the content of flavor nucleotides and flavor amino acids in mutton, thereby significantly improving the umami taste of the mutton.

[0050] There is no particular limitation on the type of sheep in the present invention, for example, the sheep include one or more of small-tailed Han sheep, large-tailed Han sheep, Northeast fine-wool sheep, Hu sheep, Tan sheep, Mongolian sheep, Dorper sheep and black goat, etc. There is no particular limitation on the feed in the present invention, for example, the feed can be granules, powders, semi-solid and liquid feeds, etc.

[0051] There is no particular limitation on the drinking water for sheep in the present invention. For example, the drinking water can be tap water, groundwater, stream water, river water, lake or reservoir water, etc.

[0052] There is no particular restriction on the feeding method or drinking water for the sheep in the present invention, and conventional feeding methods can be used for feeding or drinking water.

[0053] III. Examples

[0054] The present invention is described in detail below through specific examples. The experimental methods described below, unless otherwise specified, are all routine laboratory methods. The experimental materials described below, unless otherwise specified, can all be obtained from commercial channels.

[0055] The strain used in the experiment of the present invention is Kluyveromyces marxianus YZC-01 (Kluyveromyces marxianus YZC-01) screened from the intestines of healthy Chinese people. The strain deposit number is: CGMCC NO.29514), and the deposit date is January 4, 2024.

[0056] Embodiment 1:

[0057] (1) Kluyveromyces marxianus was aerobically fermented in a liquid culture medium at 30°C for 3 days. The colony forming units of Kluyveromyces marxianus in the culture were 5.0×10 6 / mL.

[0058] (2) The fermentation broth of Kluyveromyces marxianus was centrifuged, and the cells were harvested and freeze-dried. When the moisture content was less than 8%, the solid Kluyveromyces marxianus powder was obtained after being crushed through a 100-mesh sieve. The colony forming unit was 3.0×10 8 / g.

[0059] (3) 0.1 kg of Kluyveromyces marxianus powder was added to 1000 kg of feed, and the mixture was thoroughly stirred and mixed at a total mass ratio of 0.01:100, and then directly fed to the small-tailed Han sheep.

[0060] Embodiment 2:

[0061] Steps (1) and (2) in this embodiment are the same as those in Example 1.

[0062] (3) 1 kg of Kluyveromyces marxianus powder was added to 1000 kg of feed, and the mixture was thoroughly stirred and mixed at a total mass ratio of 0.1:100, and then directly fed to the small-tailed Han sheep.

[0063] Embodiment 3:

[0064] Steps (1) and (2) in this embodiment are the same as those in Example 1.

[0065] (3) Add 10 kg of Kluyveromyces marxianus powder to 1000 kg of feed, stir and mix thoroughly at a total mass ratio of 1:100, and then feed directly to small-tailed Han sheep.

[0066] Embodiment 4:

[0067] In the above embodiment, solid powder of Kluyveromyces marxianus was added to the feed according to different mass fractions, and the solid powder of Kluyveromyces marxianus was fully stirred and fed to the small-tailed Han sheep. The experiment was provided with experimental group 1 (Example 1), experimental group 2 (Example 2), experimental group 3 (Example 3) and control group (solid preparation of Kluyveromyces marxianus was not added to the feed), each group had 6 parallels, and each parallel had 6 male small-tailed Han sheep. The whole experiment was carried out for 90 days, and the weight of each sheep was weighed at the beginning and end of the experiment to take the average (Table 1). At the same time, one sheep was taken from each experimental group on the 90th day of the experiment, and about 3kg of hind leg muscle was taken after slaughter. The national standard method (GB5413.40-2016 National Food Safety Standard: Determination of Nucleotides in Infant Food and Dairy Products; GB5009.124-2016 National Food Safety Standard: Determination of Amino Acids in Food) was used to determine the content of flavor nucleotides and flavor amino acids in mutton, and the mean results of each group of data are shown in Table 1, Table 2 and Table 3, respectively.

[0068] Table 1 Effect of Kluyveromyces marxianus on promoting the growth of small-tailed Han sheep

[0069] Detection indicators\experimental categories Control group Experimental Group 1 Experimental Group 2 Experimental Group 3 Initial average weight of sheep (kg / head) 16.8 17.0 16.1 17.2 Average weight of sheep in the experiment for 90 days (kg / sheep) 46.5 47.6 48.5 49.8 Average weight gain per head (kg / head) 29.7 30.6 32.4 32.6 Increase growth rate (%) 3.0 9.1 9.8

[0070] Table 1 shows that as the mass fraction of the solid preparation of Kluyveromyces marxianus added to the feed increases, the effect of promoting the growth of sheep becomes more obvious after feeding for 90 consecutive days, and the growth rate of sheep is increased from 3.0% to 9.8%, indicating that feeding Kluyveromyces marxianus can significantly increase the growth rate of sheep.

[0071] Table 2 Effect of Kluyveromyces marxianus on improving the content of flavor nucleotides in small-tailed Han mutton

[0072]

[0073]

[0074] Table 2 shows that as the mass fraction of solid preparation of Kluyveromyces marxianus added to the feed increases, the content of inosine nucleotide in mutton increases significantly after feeding sheep for 90 consecutive days, and the increase range increases from 1.29% to 2.81%.

[0075] Table 3 Effect of Kluyveromyces marxianus on improving the content of flavor amino acids in small-tailed Han mutton

[0076] Detection indicators\experimental categories Control group Experimental Group 1 Experimental Group 2 Experimental Group 3 Glutamic acid (g / 100g) 2.52 2.73 3.03 3.09 Serine(g / 100g) 0.64 0.71 0.91 0.92 Glycine (g / 100g) 0.79 0.85 1.08 1.09 Isoleucine (g / 100g) 0.74 0.80 0.92 0.94 Leucine (g / 100g) 1.32 1.40 1.61 1.63 Alanine(g / 100g) 0.93 0.98 1.15 1.18 Proline (g / 100g) 0.66 0.71 0.86 0.88 Total (g / 100g) 7.60 8.18 9.56 9.73 Increase the proportion of flavor amino acids (%) 7.6 23.8 28.0

[0077] Table 3 shows that as the mass fraction of solid preparation of Kluyveromyces marxianus added to the feed increases, the content of flavor amino acids in mutton increases more significantly after feeding sheep for 90 consecutive days, and the increase increases from 7.6% to 28.0%.

[0078] The above results show that as the mass fraction of the solid preparation of Kluyveromyces marxianus added to the solid feed increases from 0.01% to 1.00%, not only the growth rate of the sheep is accelerated (Table 1), but also the content of flavor nucleotides (Table 2) and flavor amino acids (Table 3) in the mutton is increased. In the experimental group 3, that is, Example 3, when the solid preparation of Kluyveromyces marxianus was added to the feed at a mass fraction of 1%, the content of flavor nucleotides (Table 2) and flavor amino acids (Table 3) in the mutton was significantly increased, thereby greatly improving the umami taste of the mutton, which has important and broad application prospects.

[0079] It should be noted that the embodiments described above are only preferred embodiments of the present invention, which are used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A solid preparation of Kluyveromyces marxianus YZC-01 for improving the umami taste of mutton, comprising living cells of Kluyveromyces marxianus YZC-01 strain.

2. The solid preparation according to claim 1, characterized in that The solid preparation of Kluyveromyces marxianus YZC-01 is a solid bacterial powder of Kluyveromyces marxianus YZC-01 obtained by fermenting and culturing the Kluyveromyces marxianus YZC-01 strain, harvesting cells by centrifugation, freeze-drying, crushing and passing through a 100-mesh sieve; preferably, the deposit number of the Kluyveromyces marxianus YZC-01 strain is CGMCC NO.29514.

3. The solid preparation according to claim 1 or 2, characterized in that In the solid bacterial powder of Kluyveromyces marxianus YZC-01, the colony forming unit (CFU) of Kluyveromyces marxianus YZC-01 strain is 1.0×10 8 / g to 10.0×10 8 / g; and / or, the moisture content of the solid powder of Kluyveromyces marxianus YZC-01 is lower than 8wt%.

4. The solid preparation according to any one of claims 1 to 3, characterized in that The solid preparation can increase the content of flavor nucleotides in mutton after being fed to sheep; preferably, the solid preparation can increase the content of flavor nucleotides in mutton by 1.29wt%-2.81wt% after being fed to sheep; and / or, the flavor nucleotide is hypoxanthine nucleotide.

5. The solid preparation according to any one of claims 1 to 4, characterized in that The solid preparation can increase the content of flavor amino acids in mutton after being fed to sheep; preferably, the solid preparation can increase the content of flavor amino acids in mutton by 7.6wt%-28.0wt% after being fed to sheep; and / or, the flavor amino acids include one or more of glutamic acid, serine, glycine, isoleucine, leucine, alanine and proline.

6. Use of the solid preparation of Kluyveromyces marxianus YZC-01 as claimed in any one of claims 1 to 5 in improving the umami taste of mutton.

7. The use according to claim 6, characterized in that: The application comprises adding the solid preparation into the sheep's feed and / or the sheep's drinking water, stirring the mixture evenly and then feeding the mixture to the sheep.

8. The use according to claim 7, characterized in that: Based on the total weight of the sheep feed and / or the sheep drinking water, the solid preparation is added to the sheep feed and / or the sheep drinking water in an amount of 0.01wt% to 1.0wt%, preferably 0.1wt% to 1.0wt%, and more preferably 1.0wt%.

9. The use according to claim 7 or 8, characterized in that: The feed comprises one or more of granules, powders, semisolids and liquid feeds.

10. The use according to any one of claims 6 to 9, characterized in that: The sheep include one or more of small-tail Han sheep, large-tail Han sheep, Northeast fine-wool sheep, Hu sheep, Tan sheep, Mongolian sheep, Dorper sheep and black goat.

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