JP5885245B2 - Cattle breeding method - Google Patents

Description

  The present invention relates to a method for raising cattle with reduced isoflavone concentration in meat.

  Among the components contained in food and drink, isoflavones typified by genistein are polyphenols produced in plants. Isoflavones are known to be effective in preventing and improving climacteric disorder, arteriosclerosis, and osteoporosis because of their affinity for estrogen receptors. In general, when a soy product is ingested, isoflavones are hydrolyzed in the intestine and absorbed into the body as genistein, an aglycon, and the absorbed soy isoflavones are conjugated in the liver and excreted into the bile. It circulates and partly binds to estrogen receptors or is excreted from the body via the kidneys.

  On the other hand, it has become known that there is a possibility of harming health, such as exacerbation of hormone-dependent breast cancer by excessive intake of genistein. For this reason, the Food Safety Commission recommends taking an appropriate amount of isoflavones.

  In addition to soybeans, there are meat products as protein sources. Isoflavones are contained in plants such as soybeans, but a considerable amount of isoflavones are also contained in cattle fed with grains such as soybeans as feed. Conventional cattle breeding involves breeding from weaning to shipping with rough feed and growth while increasing the amount of concentrated feed, and raising the level of crossbreeding by feeding the concentrated feed. Can be made. For this reason, isoflavones are taken into the body by the grains blended in the concentrated feed, which contributes to an increase in the concentration of isoflavones in the meat. Also, for the purpose of increasing meat quality, it is common to narrow the barn and fatten without exercising. In addition, dairy cows are also beef cows after finishing their role as milking cows, but the isoflavone content tends to increase due to the feeding of concentrated feed. In this way, due to a decrease in liver function caused by a heavy supply of dense feed, poultry feeding, and lack of exercise, it is easy to accumulate isoflavones in the meat, which requires attention.

  Cattle livestock production differs from poultry and pig farming in that it can be fed and produced with grass resources that do not compete with human food. The accumulation of isoflavones in cattle meat is due to heavy use of concentrated feed containing a large amount of grains, and is the result of introduction to satisfy the demand for high fat crossing ratios for Japanese beef by consumers. In fact, in order to improve the rate of crossbreeding, beef production according to the characteristics of Japanese black beef is recommended, and fattening methods centering on crossbreeding based on imported cereals are widespread. In other words, cattle breeding is performed by increasing the ratio of the concentrated feed to the roughage as the fattening progresses, and further by feeding the concentrated feed consisting of cereals and soybean meal before shipment to increase body fat. For this reason, when the intake of concentrated feed is simply reduced, the amount of nutrient components is reduced, and there may be a negative effect of suffering from other diseases due to lack of nutrition. Therefore, it is not possible to reduce the genistein concentration simply by switching to roughage. In addition, if a drug is used to prevent morbidity, the safety of meat quality is impaired. Therefore, a safer method for raising cattle having meat quality with a reduced isoflavone content is desired.

  In addition, cattle excrement becomes pasture fertilizer, but if you use hormonal agents or antibiotics during breeding, they are not only retained in the meat but also mixed in cattle excretion. The safety of is harmed. It is useful to use healthy cattle excrement as natural fertilizer for pasture to achieve resource recycling livestock that reuses excrement. In conventional pastoral methods, if the use of hormones and antibiotics is completely refrained, the aim is to increase body fat, so the walking distance of cattle is short and the resistance of cattle is reduced, etc. Difficult to do. Therefore, a safer method for raising cattle having meat quality with a reduced isoflavone content is desired.

  The ultimate of the above-mentioned resource circulation type livestock production is that a mother cow gives birth to a calf and fattens this newborn calf. However, traditional Japanese beef farmers are broadly divided into breeding farms that breed mother cows and calves (beef cattle) born from the cows, and fattening farms that fatten the cows and ship them to the meat center. In the conventional cattle breeding method, as a result of improvement with emphasis on fat crossing, there is a tendency for fertility such as lactation ability and child rearing ability to be neglected, and mother cows have less milk production, so the new calf's immune ability Decreased, and there were problems such as frequent occurrence of neonatal calf diarrhea. For this reason, frozen colostrum and powdered colostrum for breast milk have been developed, or mother and child separation feeding techniques for artificial feeding are being developed. However, these are all solved by the artificial technique and are expensive. Meat safety relies on inherently healthy meat. Therefore, breeding and fattening are integrated, new calves can ensure sufficient immune resistance by ingesting sufficient breast milk, have healthy meat quality by sufficient exercise, and have a low isoflavone content. Is desired.

  Meat is a food that contains proteins, fats, and minerals and has excellent nutritional value. It is preferable that it can be taken in without worrying about the accumulation of specific components. On the other hand, if the meat quality is reduced, the purchase of consumers is suppressed, and the significance of producing livestock meat with a reduced isoflavone content is reduced.

  In view of the above situation, an object of the present invention is to provide a method for raising cattle having meat quality in which the content of isoflavones such as genistein is reduced while raising healthy cattle.

  The present inventors have studied in detail the breeding method of cattle, and at least three months before shipment, the cattle are grazed with a grazing area of 0.3 to 10 ares per head and fed with roughage. As a result, it was found that the isoflavone content in the meat was reduced, and the present invention was completed.

That is, according to the present invention, in a method for raising cattle fed with concentrated feed, at least three months before shipment, the cattle are grazed with a grazing area of 0.3 to 10 ares per head and fed roughage. It is intended to provide a method for raising cattle with reduced isoflavone concentration in meat, characterized by

  In addition, the present invention provides the method for raising cattle described above, wherein the cattle are Japanese shorthorn or crossbreed with Japanese shorthorn.

  According to the present invention, cattle with a reduced isoflavone content by grazing cattle with a grazing area of 0.3 to 10 ares per head and feeding them with roughage for at least three months before shipment. Can be reared.

It is a figure which shows the jenistein value in the meat of the cattle of Example 1 and Comparative Example 1. It is a figure which shows the blood jenistein value of the cattle of Example 2 and Comparative Example 2. It is a figure which shows the blood jenistein value of the cattle of Example 3 and Comparative Example 3.

  The present invention relates to isoflavone concentration in meat characterized by grazing cattle with a grazing area of 0.3 to 10 ares per head and feeding roughage for at least three months before shipping Provides a method for raising cattle that has been reduced. Hereinafter, the present invention will be described in detail.

(1) Cattle Since the present invention aims to reduce the content of isoflavones in meat, the target cattle are preferably so-called meat-specific species, such as Japanese black cattle, red hair Japanese species, Japanese short angle species, non-angled species, Aberdeen Angus species, Hereford species, Saler species, Charolais species, and hybrids thereof may be used. The cattle may be female, male or steer. However, since the present invention feeds and raises only the roughage for at least 3 months, a cattle breed with excellent utilization of the roughage is suitable. Examples of such cattle breeds include Japanese shorthorn breeds, crossbreeds with Japanese shorthorn breeds, Japanese black beef, Aberdeen Angus, Hereford and Charolais.

(2) Breeding ground These cattle may be bred in any breeding ground before the implementation of the present invention. For example, steers are generally raised from weaning to shipping in house-houses while increasing the amount of concentrated feed in line with growth from roughage. Also, for the purpose of increasing meat quality, it is common to narrow the barn and fatten without exercising. Dairy cows are also beef cattle after completing their role as milking cows, but are kept in the house by feeding concentrated feed. In the present invention, even a cattle cattle housed and housed with such a concentrated feed is fed and bred for at least 3 months prior to shipment, and 0.3 to 10 per head. The content of isoflavones in meat can be reduced by grazing cattle in the grazing area of Earl. However, considering that cattle excreta can be reused as fertilizer for pastures that make up the roughage, it depends on the livestock area, but it is grazed in the summer and kept in the summer mountain winter village system that is housed in the winter. It is preferable to be a place. Grazing ensures an appropriate amount of exercise, so the morbidity of cattle is low and the dosage of drugs is reduced, and the transfer of these drugs to excreta can be avoided. In addition, since the excreta is reduced to the grass, the nutrients can be circulated in the grassland, and the use of chemical fertilizer can be avoided. Furthermore, it is preferable that breeding and fattening are managed in series. This is because a newborn calf can ingest breast milk, so that immunity can be secured and administration of antibiotics and the like can be reduced from the newborn calf stage.

(3) Breeding method (i) Period The present invention aims to reduce the content of isoflavones in the meat of cattle, with a grazing area of 0.3 to 10 ares per head for at least three months before shipment. It is only necessary to graze cattle and feed roughage. For example, beef cattle are generally shipped at the age of 2-3 years. In fattening, bulls are generally castrated at the age of 2 months for the purpose of improving fatiness and the purchased bare cows are shipped after being fattened for about 20 months. On the other hand, a cow for breeding is shipped after repeating the cycle of pregnancy, childbirth, and milking about four times and finishing the role as a cow. Therefore, the breeding period of cattle cattle targeted in the present invention can be appropriately selected according to sex and use other than the above-described predetermined period before shipment.

In the present invention, cattle are grazed at a grazing area of 0.3 to 10 ares per head and fed roughage for at least 3 months before shipment, but at least for 3 months before shipment. This is because it has been found that the isoflavone concentration accumulated in the meat can be reduced by grazing during the above period and feeding the roughage, regardless of which method is used for breeding. For example, if November is the shipping month, cattle should be grazed at a grazing area of 0.3 to 10 ares and fed roughage for at least three months from August to October. . In addition, when raising cattle by grazing, a vast pasture is required and a production area is limited. For this reason, there are some farms where it is difficult to secure pasture in winter and it is necessary to keep a house. In the present invention, at least 3 months prior to shipment, more preferably at least 4 months prior to shipment, particularly preferably 6 months prior to shipment may be raised under conditions of grazing and roughage feeding, and grazing during other periods. It does not matter whether or not there is roughage feed. Preferably, the grazing period may be 3 months or more before shipment, and preferably 3 to 36 months before shipment, more preferably before shipment, considering that cattle are shipped at 2 to 3 years of age. 6 to 30 months.
The roughage should be fed for at least 3 months before shipment, preferably the entire period before shipment, more preferably 3 to 20 months before shipment, and particularly preferably 6 to 20 months before shipment. It is. If the period during which the roughage is fed is less than 3 months before shipment, the concentration of isoflavones in the meat may not be sufficiently reduced. In addition, although the period for feeding roughage may exceed 20 months, the significance of feeding the concentrated feed may be reduced if the rich feed is fed before breeding.

  In the present invention, “months before shipment” means consecutive months before the shipment month of the shipment year. In addition, when house-keeping after the ○ months have elapsed due to the grazing and rough-use feeding, it is preferable to ship the concentrate without feeding it. In response to the shipping status, grazing environment, seasonal fluctuations, etc., avoid feeding concentrated feed even after a period of ○ months due to grazing and rough feeding, even if housekeeping is performed for a certain period immediately before shipping This is because an increase in the isoflavone content in the meat can be avoided.

  In the present invention, “reducing the isoflavone concentration in the meat” means that the isoflavone concentration in the meat of the cattle is further reduced as compared with the conventional breeding method using concentrated feed. For at least 3 months prior to shipping, cattle are grazed with a grazing area of 0.3 to 10 ares per head and fed roughage, so that the breeding method prior to such treatment, that is, conventional cattle The isoflavone concentration in meat can be reduced as compared with the case of this breeding method. It is also possible to breed new calves and young cows by grazing and roughage treatment for 36 months, but in that case, it is not a comparison with the pre-treatment but conventional conventional breeding. This means that the concentration of isoflavones in meat is lower than that of cattle by

(Ii) Feed In the breeding method of the present invention, the “rough feed” fed to cattle means a feed containing no cereals such as dent corn. Accordingly, the “rough feed” in the present invention refers to foliage such as grass, wild grass, green cutting, straw, and leaves, and crude fibers such as hay, silage, alfalfa meal, and beet pulp. Grass seeds include rice straw, alfalfa, timothy, orchard, reed canary grass, white clover, red clover, perennial ryegrass, Kentucky bluegrass, and medfescue. It is necessary to ingest approximately 30 to 60 kg, preferably 40 to 50 kg per day as fresh grass. The roughage has a lower isoflavone concentration than the concentrated feed, and therefore the concentration of isoflavone in the meat can be advantageously reduced.

  In the present invention, it is desirable to use a roughage that does not use any chemical fertilizer at the place where the roughage and pasture are prepared. This is because securing a pasture that does not use chemical fertilizers can withstand aging of the soil and is easy to handle.

  However, in this invention, it is not necessary to restrict | limit to the above-mentioned roughage over the whole period of breeding, and the feed containing cereal can be fed before three months of shipment. This is because even if a concentrated feed is fed, the concentration of genistein in meat can be reduced by breeding by grazing and feeding roughage for at least 3 months before shipment.

  In the present invention, “concentrate feed” is composed of conventional ingredients mainly composed of cereals. Concentrated feed ingredients include, for example, various types of corn including dent corn, milo, wheat, barley, rye, oats, flour, brown rice, millet, soybeans, quinako, cassava; soybean oil cake, molted soybean oil cake , Oilseed rape, oilseed rape, groundnut oil, linseed oil, sesame oil, palm oil, sunflower oil, safflower oil, palm kernel oil, kapok oil, rice bran, rice bran, bran, bran, etc .; Manufacturing meals such as meal, starch cake, honey, soy sauce cake, beer cake, soybean cake, corn gluten feed, beet pulp, bagasse, tofu cake, malt root, citrus peel, tangerine juice cake; fish meal, fish meal, fish Soluble, meat flour, meat-and-bone meal, blood meal, feather meal, rice bran oil, skim milk powder, whey, animal fats (beef oil, pork oil, Oil, etc.), animal feed such as beer yeast, torula yeast; mineral feed such as salt, calcium source (calcium carbonate, limestone powder, oyster shell, etc.), phosphorus source (dilime phosphate, trilime phosphate, etc.) Vitamins, amino acids, minerals and the like. The concentrated feed may contain other additives such as antibiotics, antibacterial agents, enzymes, antifungal agents, antioxidants, pigments, sweeteners, fragrances, and binders as necessary.

  In the concentrated feed, cereals are usually contained in a proportion of about 30 to 80% by weight, preferably about 40 to 80% by weight. The concentrated feed may be a mixed feed, but is usually a mixed feed in many cases. The form of the mixed feed is not particularly limited, and may be a solid form such as a mash, pellet, crumble, cube, or flake. In addition, about the ratio of a feed component, according to the kind of ruminant, you can refer to "Japan breeding standard" central livestock association (1987). In general, the breeding period is divided into the first period, the middle period, and the second period, and for example, the feed quality can be improved by improving the meat quality by setting the feed period as 7 months, 7 months, and 6 months, respectively. As the child grows up to the living body, the function of the rumen improves and the body grows. For example, the first period is the period for promoting the growth of the internal organs and skeleton of the bull and attaching muscles and fat, the middle period is the period for accumulating fat in the muscles, and the latter period is marbling between the muscles. It is a period to add fat. In the present invention, feed suitable for each stage can be fed in response to the function of the rumen and the growth of the body of such cattle.

  For example, in the first period, the ratio of the roughage to the concentrated feed is set to 20 to 70% by mass, in the middle period, the ratio of the roughage to the concentrated feed is increased to 30 to 80% by mass, and in the latter period, the ratio of the roughage to the concentrated feed is increased. A mixture ratio can be 90-100 mass%. As described above, in the present invention, only the roughage may be fed over the entire period from weaning to shipment.

(Iii) Catabolic metabolism In the present invention, cattle are grazed with a grazing area of 0.3 to 10 ares per head, so the walking distance of cattle per day is 10 to 30 km. This is because it was found that when the walking distance is in the above range, the catabolic ability of cattle is activated and the decomposition of the isoflavone concentration accumulated in the meat is promoted.

  That is, in the present invention, cattle are grazed with a grazing area of 0.3 to 10 ares per head because catabolism is promoted and the jenistein concentration can be lowered. As long as catabolism can be promoted, the grazing area of one cattle is not limited to 0.3 to 10 ares, and it may be 0.5 to 8 ares or 0.5 to 5 ares. This is because catabolism can be promoted by securing a walking distance. Grazing on a large area increases the amount of exercise and improves the ability to metabolize isoflavones by enhancing liver function. In addition, according to the feeding of roughage, the calorie per unit weight of the feed is reduced, so that catabolic metabolism is promoted, and as a result, the isoflavone concentration in meat can be reduced. The grass that constitutes the roughage is also advantageous in that it has a low isoflavone concentration.

  By feeding the roughage in a predetermined period before shipment and grazing in a predetermined area, as shown in the examples described later, liver functions such as AST (aspartate aminotransferase) and GGT (γ-glutamyltranspeptidase) The enzyme activity as an index increases within the normal range, and catabolism is promoted.

  In addition, there is no limitation in particular as a method of adjusting the said walking distance, For example, you may breed by adjusting the grazing area of one cattle. The daily calorie consumption is roughly divided into those based on basal metabolic rate and exercise amount, but since the amount of exercise increases corresponding to the grazing area, the calorie consumption per day is improved by increasing the grazing area. be able to.

  EXAMPLES Next, although an Example is given and this invention is demonstrated concretely, these Examples do not restrict | limit this invention at all.

Example 1
As shown in Table 1, Japanese short-horned males (N), Japanese short-horned cattle (N), Japanese short-horned males (female) and Saler breed (male) hybrids (SN) Three crossbreds (NSN) produced by backcrossing (bred cattle) were raised as bare cattle. After the birth, the cows were bred with the milk of the mother cow, and were bred in the past 5 to 10 months, and the rest were housed. The shipping year was from January to April in accordance with the November shipping, and was raised by grazing from May to October. Artificial feeding was not performed, and the animals were raised only with grass. The grass does not contain cereals. Grazing intake at the time of grazing was about 30 to 60 kg as raw grass and about 15 to 20 L / day for water. The grazing area was 1a per head, and the walking distance by grazing was 10-30 km / day. None of the cattle affected by the disease during the breeding period. The excrement during grazing was used as a fertilizer for pasture.
In addition, over the whole period of breeding, concentrated feed was not given at the time of housekeeping, but roll wrap and glass silage were mainly given. Roll wrap and grass silage are about 20% each of the basic grass species Timothy, Orchard, and Reed Canary Grass. In addition, white clover is about 15%, red clover is 0-15%, perennial ryegrass, Kentucky bluegrass, and medfescue. In total, the composition was 5 to 20%. This is the same as pasture vegetation.

  Blood was collected from the above 6 animals in May (before grazing), August (during grazing), and October (after grazing), and blood genistein concentration, blood AST, and GGT were measured. The results are shown in Tables 2 and 3. In addition, after shipment, the longest muscle (loin meat) was collected and the genistein concentration was measured. Table 2 shows the genistein concentration of loin meat.

(Comparative Example 1)
As shown in Table 1, Japanese black breed (B) was considered to be a group of 4 to 6 cattle from the time of introduction of bare cattle. The cow bed per head was 6-7 m ² . The composition of the concentrated feed used at this time is 12 to 17 months old, 0.2 kg mineral, 1.5 kg beer koji, 1.0 kg pressed corn, 5.0 kg pressed barley, 20 kg super elite, 18 After the month, it was 0.2 kg of minerals, 2.0 kg of beer koji, 1.0 kg of pressed corn, 7.0 kg of pressed barley, and 1 kg of super elite.
After shipment, the longest muscle (loin meat) was collected and the genistein concentration was measured, and found to be 37.7 ± 3.0 nmol / kg.

(Example 2)
Three Japanese shorthorn species (N) (stetle) were targeted. After the birth, the cows were bred with the milk of the mother cow, and were bred in the past 5 to 10 months, and the rest were housed. The shipment year was from January to April in accordance with the December shipment, and was raised only by grazing from May to October. The intake at the time of grazing was about 30 to 60 kg as raw grass and about 15 to 20 L / day for water. The grazing area was 1a per head, and the walking distance by grazing was 10-30 km / day. In addition, after grazing, during the period until shipping in December, sheltering with roughage was performed.
None of the cattle affected by the disease during the breeding period. None of the patients suffered from acidosis, lobitis, liver abscess, rumen villi attachment, or other digestive disorders. Blood was collected in December of the shipment year, and the blood genistein concentration was measured. As a result, it was 17.2 ± 5.1 nmol / L.

(Comparative Example 2)
Three Japanese shorthorn species (N) (stetle) were targeted. After the birth, they were raised in the pasture from May to October, and others were housed. The shipment year was from January to April in accordance with the December shipment, and was raised only by grazing from May to October. The grass had 10% of dent corn that can be regarded as a kind of cereal because seeds have developed and have cereal ingredients. Grazing intake at grazing was 30-60 kg as raw grass, and water intake was about 15-20 L / day. The grazing area was 1a per head, and the walking distance by grazing was 10-30 km / day.
When housed, the same amount of concentrated feed was fed together with roll wrap and grass silage. The composition of this concentrated feed is 12 to 17 months of age, with a composition ratio of 0.2 kg mineral, 1.5 kg beer lees, 1.0 kg pressed corn, 5.0 kg pressed barley, 20 kg super elite, 18 After the month, the blending ratio was 0.2 kg of minerals, 2.0 kg of beer koji, 1.0 kg of pressed corn, 7.0 kg of pressed barley, and 1 kg of super elite. The roll wrap / glass silage is obtained by adding 10% of dent corn silage to the grass seed of Example 1.
There were no cases of acidosis, lobeitis, liver abscess, rumen villi attachment, or other gastrointestinal diseases during the breeding period.
Blood was collected in December of the shipment year, and the blood genistein concentration was measured to be 31.8 ± 9.1 nmol / L.

(Example 3)
Three Japanese shorthorn species (N) (stetle) were targeted. After the birth, the cows were bred with the milk of the mother cow, and were bred in the past 5 to 10 months, and the rest were housed. The shipment year was from January to April in accordance with the December shipment, and was raised only by grazing from May to October. The intake at the time of grazing was about 30 to 60 kg as raw grass and about 15 to 20 L / day for water. The grazing area was 1a per head, and the walking distance by grazing was 10-30 km / day. The feed and other conditions for feeding are the same as in Example 1. In addition, after grazing, during the period until shipment, sheltering with roughage was performed. In addition, no cattle suffered from the disease during the breeding period.
Blood was collected in July of the grazing season of the shipping year, and the blood genistein concentration was measured to be 15.9 ± 2.4 nmol / L.

(Comparative Example 3)
Three Japanese shorthorn species (N) (stetle) were targeted. After she was born, she was housed until shipment. The cow bed per head was 6-7 m ² . In addition, the same roll wrap and glass silage as Example 1 were given, without giving a concentrated feed at the time of housing.
None of the cattle affected by the disease during the breeding period.
Blood was collected in July of the grazing season of the shipping year, and the blood genistein concentration was measured to be 36.6 ± 0.2 nmol / L.

(result)
(1) As shown in Table 2, the concentration of jenistein in the blood of the cattle of Example 1 grazing and fed with roughage was from before grazing (May) to during grazing (August) and after grazing (October). There was a significant decrease. Thus, it was found that the concentration of isoflavone in the blood can be gradually reduced within the grazing period by feeding only the roughage and grazing cattle with an area of 0.3 to 10 ares per head.
(2) The meat jenistein value of Japanese short-horned varieties (N) by grazing from May to October before feeding in Example 1 and feeding roughage is 24.5 ± 1.5 nmol / kg. The value of genistein in meat of Japanese black beef (B) fed with a concentrated feed is 37.7 ± 3.0 nmol / kg. The meat jenistein values of Example 1 and Comparative Example 1 are shown in FIG. 1 (** in the figure indicates that there is a significant difference between Examples and Comparative Examples in Student's T test). Due to grazing and roughage, the jenistein level in Japanese shorthorn meat was reduced to 2/3 that of Japanese black beef. As a result, Japanese short-horned varieties are superior in forage utilization, and the concentration of isoflavones in meat can be significantly reduced due to feeding and grazing of forage compared to cattle fed concentrated feed. found.
(3) As shown in Table 3, the blood AST values and GGT values of the cattle raised with grazing and roughage in Example 1 both increased within the normal range. This change indicates that cattle health has been improved by forage feeding and grazing. The normal values of AST and GGT for cattle are 45 to 100 U / L and 11 to 30 U / L, respectively.
(4) When comparing the blood genistein values of Example 2 which was grazed and fed roughage and Comparative Example 2 which was grazed but fed concentrated feed, as shown in FIG. 2, the roughage shown in Example 2 In the figure, ** in the figure indicates that there is a significant difference between the Example and the Comparative Example in the Student's T test. This indicates that the blood genistein value varies depending on the feed to be fed. It has been found that the supply of roughage with low genistein content can significantly reduce blood genistein levels.
(5) When Example 3 reared by grazing and roughage feeding was compared with Comparative Example 3 housed by roughage, the cattle of Example 3 had a blood jenistein level as shown in FIG. (** in the figure indicates that there is a significant difference between Example and Comparative Example in Student's T test). This is presumably because blood genistein levels were reduced not only by feeding roughage but also by catabolism by grazing.

  According to the present invention, cattle with reduced isoflavone concentrations that contribute to tumors such as breast cancer can be bred.

Claims (2)

In the breeding method of cattle cattle fed with concentrated feed,
Cattle with reduced isoflavone concentration in meat, characterized by grazing cattle with a grazing area of 0.3 to 10 ares per head and feeding them with roughage for at least three months before shipping Breeding method. The method for raising cattle according to claim 1, wherein the cattle are Japanese shorthorn or crossbreed with Japanese shorthorn.

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