home > Control > The process of extracting milk from a cow 6. Machine milking of cows. Physiological bases of the process of machine milking of cows. Methods for extracting milk from a cow's udder


The process of extracting milk from a cow 6. Machine milking of cows. Physiological bases of the process of machine milking of cows. Methods for extracting milk from a cow's udder





Features of milking cattle

Milking is the process of obtaining milk from farm animals (cows, goats, sheep, mares, etc.).

In a lactating cow, milk is formed in the udder in the intervals between milkings and is retained in it due to the capillarity of the mammary gland, the special arrangement of the ducts and the presence of sphincters (constrictor muscles) in the nipples. Milking is carried out due to complex milk ejection reflexes. Under the influence of irritation of the nerve endings of the mammary gland during milking, the sphincters of the nipples relax, the smooth muscles of the udder contract, and milk is removed from the tanks and large excretory ducts. After a few seconds, under the influence of the hormone oxytocin, the stellate cells around the alveoli contract, the alveoli shrink, and the milk from them passes into the ducts and cisterns. However, even after thorough milking, a certain amount (10-15%) of milk (residual milk) with a fat content of 9-12% remains in the udder.

In lactating cows, over time, conditioned reflexes of milk release to the environment are formed. The noise of the engine of the milking machine, the appearance of a milkmaid, and other conditioned stimuli cause compression of the alveoli and the release of a hormone from the pituitary gland; Therefore, when milking, it is important to observe silence, to maintain the established order.

The frequency of milking is set so that in the intervals between milkings the udder is filled with milk and milk formation is not inhibited. Usually cows are milked 2-3 times a day, highly productive and freshly calved 3-4 times. Before starting, the number of milkings is gradually reduced.

Cows are milked two and three times a day. With three times milking, in some cases, 10% more milk is obtained than with two times. But this is typical for cows with a small udder capacity. In cows with a large udder capacity, milk yield does not increase in such cases. With a reduction in the number of milkings from three to two, labor costs are reduced by 25-30%.

Compliance with the rules of milking cows helps to obtain maximum milk yield. The milking process consists of the main process and auxiliary operations. In the main process of milking milk from the udder of cows by the apparatus, the operator does not directly participate. Auxiliary operations are divided into preparatory and final, which are performed by the operator on non-automated installations.

There are six preparatory operations: the transition of the operator with the milking machine to the next cow, washing the udder with warm water at 40-45 ° C, wiping it with a towel, massaging the udder, milking the first streams of milk and putting milking cups on the teats. There are also six final operations: the operator's transition to the cow, machine milking, turning off and removing teat cups from the teats, monitoring the condition of the udder, draining milk.

Especially beneficial effect on the completeness of milking and the fat content in milk is udder massage, which increases milk yield by 8-12% and fat content in milk up to 1%. So, in the first portions of milk contains 0.5-0.7% fat, and in the last - 8-12%.

The health status of a cow largely determines its productivity. For example, in case of tuberculosis, the milk yield of cows decreases by 20-35% compared to healthy animals, and in case of brucellosis, by 40-60%. Mastitis, diseases of the limbs, diseases of reproduction, metabolism reduce milk yield by 20-50%.

Machine milking

With machine milking, the most favorable physiological conditions are created for removing milk from the udder: all four parts of the udder are simultaneously milked by the machine.

On tie-down farms, cows are milked in barn stalls using milking machines with a milk line of the ADM-8 type or portable buckets AD-100a, DAS-2B. When using installations with a milk pipeline, the load per operator can be increased to 50 cows.

On farms with loose-box and loose housing on deep litter, cows are milked on machine-type installations with a lower milk pipeline. For milking cows at these installations, special milking parlors are equipped on farms (Figure 1), which can be independent structures adjacent to the premises for keeping cows, or located under the same roof with them. At milking parlors, pre-milking areas are arranged, the dimensions of which depend on the livestock of one section (at the rate of 2.5-3 m 2) per head.

If there are no suitable premises in the barns, then it is necessary to build a new milking area. Its size is determined depending on the number of dairy cows and the duration of milking.

To achieve the continuity of the milking process and more complete milking on modern installations, a mechanized massage of the udder with electronic control is possible.

Nerve receptors in the skin of the udder are irritated through tactile influences, that is, when milking the first streams at the beginning of the process, test milking, washing the udder, manual massage, attaching cups and pulsing the liner during milking. To achieve optimal stimulation, the duration of a certain combination of preliminary operations for at least 60 seconds is necessary. Since all these operations are manual, they need to be reduced in time in order to achieve high labor productivity of milkers with automated milking processes. The resulting deficit in stimulation can only be compensated by increasing the stimulating effect of the pulsating liner and the stimulus function is transferred to the machine. This happens when applying the ACE Pulse method (APF - alternative pulse rate increase). Due to the interval increase in the frequency of pulsation of the teat rubber up to 200 double cycles per minute throughout the entire milking process, intense irritation of the receptors is achieved.

This method makes it possible to distribute tactile stimuli for the entire milking time with the least technical costs and make manual stimulation at the beginning of milking absolutely unnecessary. When using the ACE method, a significant increase in milk yield in cows is achieved, compared with milking machines without machine or without sufficient manual stimulation. The research results are confirmed in practice by an increase in milk yield by 5 - 8%.

Recently, a lot of modern economical equipment for milking cows has appeared on the market. An example is the Milk Master milking machine from De Laval. Used for tethered content. The basis of the design takes into account the needs of both the cow and the milker.

Milking is controlled by the flow of milk from the cow. All cows are different. They require an individual approach. The Milk Master starts in the low vacuum phase with reverse pulsation. This gently stimulates the start of the cow's milk production. As soon as the flow of milk begins to flow, the machine switches to the main milking phase with normal vacuum and pulsation levels in order to milk the milking process as quickly and efficiently as possible. The Milk Master display shows milk yield, milk flow rate or milking time. Four indicator lights show the individual milking phase. The red light on the top cover of the machine starts flashing slowly as soon as the milking of the cow is completed. Information about milk yield and flow rate makes the herd management process more progressive. An unexpected drop in milk yield can be the first signal of the onset of hunting or a symptom of a disease. The information read from the milk yield indicator is a powerful tool for tracking the effectiveness of diet changes at the start of lactation.

The device of automatic detachment of the milking machine facilitates the process of milking. This device is controlled by Milk Master. The red light starts flashing as soon as the cluster is detached from the udder.

Selection and formation of groups of cows for milking on the sites

Cows that meet the following requirements are suitable for milking cows at milking parlors:

They have a tub-shaped, cup-shaped and rounded udder, the bottom of the udder is even, its distance to the floor should be at least 45 and not more than 65 cm;

The length of the teats is from 6 to 9 cm, the diameter in the middle part after milking is from 2 to 3.2 cm, the distance between the front teats is from 6 to 20 cm, between the back, and between the front and rear from 6 to 14 cm;

The quarters of the udder must be evenly developed - the allowable difference in the duration of milking of individual quarters is not more than 1 minute;

The duration of milking a cow is no more than 7 minutes;

The allowable volume of milk after milking should be no more than 200 mg, and no more than 100 ml from a separate quarter.

The “Tandem” installation can be recommended primarily for those farms where there is not yet a herd matched in terms of milking time and milk yield rate. At the same time, in order to achieve maximum productivity on the “Herringbone” installation, cows must be matched according to the rate of milk transfer and productivity.

When transferring animals for milking in the milking parlors from linear milking machines, their accustoming is necessary. Cows are accustomed to the sounds of the milking parlor, the mass of the udder and other technological procedures.

Cows are selected into groups according to their physiological state: new calves (1-3 months after calving), the first half of lactation (3-6 months), the second half of lactation (6 months or more). Groups of queens are formed according to the duration of the milking time and the rate of milk yield. The order of movement of cows for milking should be organized taking into account their physiological state: at the beginning of new calving, then the first half of lactation and after the second half of lactation.

Machine milking technology

When machine milking cows, it is necessary to take into account the process of milk transfer, which is regulated by the nervous and humoral systems of the animal, its conditioned and unconditioned reflexes.

The process of machine milking of cows includes the preparation of the milking machine and the udder of cows for milking, the milking process itself (putting on the milking cups, monitoring the milking process, machine milking and removing the milking cups).

On milking machines such as “Tandem” or “Herringbone”, the udder is washed out of the hoses with a special sprinkler. Along with washing, the udder is lightly massaged, which contributes to a more active milk supply. Thanks to these actions, cows become ready for milk production, which is noticeable by the swelling of the udder teats, which become more elastic and pink. If the milk ejection reflex does not come after washing and wiping the udder, then the operator quickly massages, clasping the individual quarters of the udder with his fingers and stroking them down in the direction of the nipples. In some cows, the milk ejection reflex is elicited only by teat massage. Before putting on the teat cups, one or two streams of milk are removed from each nipple. When milking the first streams, the operator determines the presence of an allowance of milk, the state of the mammary gland, frees the excretory channels from bacteria contained in the first streams in large quantities.

The milking of the first streams of milk is carried out in a special mug with a removable plate or with a dark strainer. This allows you to detect a cow's disease with mastitis (presence of flakes, blood impurities, mucus and other changes in milk). For this purpose, it is advisable to use the Biotest-1 device designed by BelNIIZh, which is based on measuring the electrical conductivity of milk. You can not give the first trickles to the floor, as the milk of sick cows can be a source of infection.

When milking on installations of the “Tandem” or “Herringbone” type, the first streams of milk are given off before washing and massaging the udder. A cow that is found to have swelling, redness, induration, and sores on the udder and teat should not be machine milked. It must be milked by hand in a separate bowl. After that, hands should be thoroughly washed and disinfected.

The towel used for wiping the udder should be washed and boiled. This cow is isolated from the general herd for treatment.

Having prepared the cow, the operator immediately turns on the machine and puts on the teat cups. To do this, opening the milk tap or lowering the clamp on the milk hose, he brings the apparatus under the udder with one hand, and puts the glass on the nipples one by one with the other. To avoid suction, you need to raise the glass up, at the same time bend the milk tube so that air is not sucked into the glass. Long-term air leakage reduces the vacuum in the main pipeline, which worsens the operation of other, already operating devices. When the glasses are put on correctly, no hiss is heard, they must be put on in the following order: near back, far back, far front, near front.

When placed on the nipples, the operator takes the glasses with the right hand, with the thumb and forefinger remaining free. With their help, the nipple is directed to the teat glass. After putting on the cups, the operator must make sure that the machine is working properly and the milk is being intensively milked, only then should he approach the preparation of the next cow.

Maintenance of the sanitary condition of the milking plant and dairy equipment

Sanitization of milking equipment is carried out after each milking by performing the following operations:

Wash the outside of the milking machines with warm water from the sprayer, insert the glasses into the milk heads and prepare all the equipment for washing;

Circulate with hot (60 ± 50C) detergent solution to remove the protein-fat film;

Disinfect in order to destroy pathogenic microflora and reduce bacterial contamination;

Rinse with water to remove detergent and disinfectant residues.

Circulating washing washing - disinfecting solutions is carried out within 10-15 minutes.

In addition to washing and disinfection, milking equipment should be periodically dismantled, washed and cleaned by hand.

When circulating washing, it is necessary to disassemble the corner pipes, the milk collector, the milk counter - once a week, the milking machines - once a month.

To prevent the formation of "milk stone", washing with an alkaline detergent is alternated with an acidic one. In the absence of an acid detergent, milking equipment is washed once a week with 0.1-0.2% solutions of acids (hydrochloric, acetic or sulfuric) for 20-30 minutes.

It is necessary to strictly observe the concentration of detergents, disinfectants and the temperature of water for washing milking equipment, since the use of high concentrations, as well as very cold or hot water, leads to a change in the physical and chemical properties of rubber products and a decrease in milk quality.

Milk cooling baths, milk collection tanks and other containers are manually processed after each use in the following sequence:

a) rinse the inner surface with warm water to remove milk residues;

b) washed with a 0.5% washing solution at a temperature of 45-50ºС using brushes;

c) the remnants of the cleaning solution are washed off with warm water;

d) disinfected with a disinfectant solution;

e) washed with tap water until the disinfectant is completely removed.

When using Desmol as a detergent, additional disinfection is not required.

At least once every two weeks, you should completely disassemble the milking machines, thoroughly rinse and disinfect all its parts, paying special attention to the teat rubber. Rubber parts are checked for their further suitability, then they are kept for 30 minutes in a 1% washing solution at a temperature of 70-80 ° C, after which they are washed with ruffs and brushes and rinsed with hot water.

The remaining parts, immersed in a bath with a hot 0.5% washing solution, are washed with ruffs and brushes, then immersed in clean water at a temperature of 70-80 ° C for 20 minutes. After washing the parts, the devices are assembled and 10 liters of a hot disinfectant 0.1% solution are passed through them.

Once every 6 months, all rubber parts in the apparatus are replaced with new ones, and the removed parts, after thorough disinfection and degreasing, are placed on “rest” in special devices.

When working out milking equipment, it is necessary to pay attention to all nodes of the milk line, the internal surfaces of which are in contact with milk: milk taps, pumps, intake hoses, which must be regularly disassembled and washed with detergent and disinfectant solutions using brushes.

From the action of alkaline detergents on the inner walls of the milk pipeline, the formation of a white coating is possible. To remove it, the milk line is washed with a 0.2% solution of acetic acid or a 0.15% solution of hydrochloric acid.



Keeping a cow in the household is very beneficial, since this animal can delight the whole family with healthy dairy products. However, in order to get them, it is important not only to look after and feed your pet well, but also to milk it correctly.

It would seem that it is a simple matter, however, both the amount of milk and the general condition of the cow's body depend very much on the milking technique.

It is important not only to adapt to the nature of the animal, but also to the characteristics of its udder, the amount of milk that the cow is able to give.

Naturally, experienced milkmaids also know various ways to increase milk yield and quality of milk received, which we will gladly share with you in the article below.

We prepare not only ourselves, but also prepare the cow for the milking process

Before you start the process of milking a cow, it is very important to take care of hygiene.

First of all, it is worth cleaning the stall - fresh manure must be removed, instead of it, fresh and always dry straw is laid (sawdust is also possible).

Secondly, it is important that the barn is ventilated before this. In the summer, when there are many different insects, it is very important to close the door to the barn even before and during milking. This will slightly reduce the activity of the flies, and the cow will not fan her tail as much.

The tying of the tail also helps from this, although this will not relieve the animal of nervous tension.

Young and temperamental cows are best tied, as they can knock out a bucket of milk and spill milk on the ground, at best, throw garbage into it. But still, the cow gets used to such a process quickly, and over time she will get used to getting into a comfortable position for milking at the same time and behaving obediently throughout this process.

Experienced milkmaids advise to treat the animal very gently, trying to maintain “friendly” relations with it.

To save the cow from stress, before starting milking, it is recommended to stroke her, call her by nickname and spoil her with some kind of treat. The fact is that a cow is very good at remembering its owner because she recognizes people by smell, and responds to her kindness.

Even absurd things happen when a cow gives milk to only one person, to which she is accustomed.

Do not forget wash your own hands before milking put on a clean robe or at least an apron. Also, you need to thoroughly wash the udder, removing all accumulated dirt from it.

To wash the udder, it is better to use warm water so as not to irritate the cow. After, the udder is wiped dry.

In order to stimulate the return of cow milk, it is important pre-massage the udder. It should include light rubbing and patting, and not only on the nipples, but throughout the udder. Thanks to this, your cow will form a milk ejection reflex, the flow of milk to the nipples will increase significantly.

Features of the milking process: the main techniques and good advice

It is most convenient to milk a cow while sitting on a low bench, because the more milk a cow gives, the longer the milking process will be.

To collect milk, you need to take some kind of container - an enameled bucket or a special pail. Please note that after each milking, the vessel used for milk will need to be washed and dried. After the cow has been milked, the milk will need to be covered with either a lid or gauze to keep debris out.

There are two ways to grab the teats during milking - either just with two fingers, or with a whole fist. Although finger milking is more convenient for many (especially if the cow's teats are small), experts believe that such milking can lead to various udder problems.

For this reason, when milking, the nipples must be clasped with all fingers of the hand, that is, with a fist. In order not to rub the skin of your hands and the skin of the nipples of the cow, rub your hands before milking and lubricate them with oil.

Description of cow milking technique

A cow must be milked with both hands at the same time. The two front teats are milked first, followed by the two back teats. The bucket is placed on the floor under the udder, it can also be clamped with your feet so that it does not accidentally turn over or be knocked out by a cow.

We carry out milking:

  • Grasp the nipples with both hands and press on them with all your fingers. The brush remains motionless, but with our fingers we pull a little to the bottom, as if pulling the nipple.

    A trickle of milk should run from the nipple, hitting it in the milking machine, open our fingers a little and grab the nipple again, repeat the described action. The main thing is not to pull the nipples very hard and sharply.

  • Usually the first two streams of milk are expressed into a separate bowl. According to the condition of the milk received, it is determined whether the animal has diseases.

    Also, with the first milk, dirt comes out of the nipples.

  • It is imperative to adhere to such a milking sequence, when the front teats are first milked, and then the back ones. You need to switch from one to the other as the streams of milk are depleted.
  • You can periodically massage the udder so that new portions of milk begin to flow to the nipples.

    It is especially important to do a massage before the end of milking, then the milk will flow more fat.

  • Upon completion of milking, it is important to wipe the nipples dry, and then grease them with some greasy substance - petroleum jelly or butter. This will protect the nipples from cracking in the hot season.

How often you need to milk: get acquainted with different options and opinions

Most cows are milked three times a day.

However, some farms where animals are grazed around the clock and no additional feed other than grass is used to feed the cows practice one-time milking.

But this is done solely for economic reasons, and also due to the fact that in such conditions cows usually give a small amount of milk.

But still, if a cow is capable of producing a large amount of milk, then one-time milking will by no means suit her. But in the future, the opinions of both milkmaids and other specialists differ greatly.

Some believe that three times milking allows you to increase milk yield, others are of the opinion that the number of milkings does not affect the amount of milk received.

Probably, it would be more correct to say that if a cow is first milked three times a day, and then switched to two times a day, then in this case, drops in milk yield are more likely.

Therefore, this issue should be approached based on their own capabilities. If it is easy for you and you have enough time to milk your pet three times a day, do it three times.

If in the daytime you are too busy, and it is more convenient for you to milk only in the morning and in the evening, you will have to give preference to two-time milking.

Is it important to take into account the time of cow's milking and how does this affect the amount of milk?

The time for milking should always be about the same.

Firstly, with the help of this you will discipline your cow, and secondly, you will regulate the processes of milk accumulation in the udder.

The fact is that the more milk accumulates in it, the further it is produced slowly. But after milking and the massage carried out during her mammary glands of the cow are activated, and milk begins to be actively produced again.

If you decide to milk your pet three times a day, then intervals between two milkings should be approximately 8 hours. That is, milking should start at about 6:00 in the morning, at 12:00 in the afternoon and at 19:00 in the evening.

But with a two-time this period of time, it is advisable to increase up to 12 hours. Thus, if the cow was milked in the morning at 6:00, then in the evening this process should be started at 18:00. But still, it is important not to observe the interval between milkings, but to adhere to approximately the same time.

Even if these intervals are difficult to maintain, milking can be done either an hour earlier than the usual time, or an hour later. That is, if you usually milk a cow three times a day, then the minimum interval between milkings can be a period of 7 hours, and the maximum is 9.

Many also combine milking time with cow feeding. In fact, this is very convenient, because you do not have to go to the barn very often, first to feed, and then to milk the cow.

Problems and diseases of the cow associated with the udder and quality characteristics of milk

In cows, there are two of the most common and problematic diseases that affect the mammary glands and greatly affect the quality of the milk produced. Therefore, if you decide to keep a cow, you need to be prepared for this.

Why is leukemia dangerous and how to understand its symptoms?

Your cow can become infected with leukemia in many ways. Very often this happens when veterinarians carry out various work related to blood sampling from an animal. But in addition to blood, causative agents of leukemia can also be found in semen, milk, and amniotic fluid (that is, the disease is transmitted from mother to calf).

It is very important to limit sick animals in contact with the whole herd., since the described disease is even transmitted through blood-sucking insects. Another negative nuance of the disease is that at the first stage it is almost impossible to determine the presence of the disease.

Yes, and on the second there are no clearly visible symptoms, the disease is determined by the hematological changes that occur in the peripheral circulatory system.

Since the causative agents of leukemia are also found in milk, it cannot be eaten fresh; before that, it should be boiled well.

Unfortunately, but leukemia is not treatable. The only necessary preventive measure is the annual two-time check of the blood of animals for the presence of infection.

Thus, if necessary, you can learn about the disease in a timely manner and apply the necessary measures to isolate or destroy livestock.

Mastitis: symptoms, prevention and treatment of the disease in cows?

This disease can be identified almost immediately by the strongly inflamed mammary glands of a cow. Most often pay attention to it when milking.

Causes of mastitis may be the following factors:

  • Unsanitary conditions of detention, when the udder is poorly washed or not washed at all before milking; in the absence of regular cleaning in the corral with a cow.
  • During dry summer periods when milk stagnates in the udder. Very often, during the dry period, mastitis manifests itself due to the fact that it was not treated earlier.
  • With catarrhal diseases of the animal, when it has a high temperature for long periods of time.
  • With improper milking.

Thus, the prevention of mastitis may well be full feeding, as well as compliance with all necessary sanitary standards for keeping cows.

In case of mastitis, in no case should milking be used using a special automated machine.

You can determine mastitis by the clots that appear in the milk, pus, and sometimes even bloody traces. True, this disease also has a latent form, when its presence in an animal is determined only on the basis of special checks.

For example, you can add Mastidin to a few drops of milk. If there is a disease, the milk will become like jelly and the treatment of the cow should be started immediately.

It is most effective to use antibiotics, although there are many folk remedies.

Since mastitis can be caused by different types of bacteria, the drug should also be prescribed individually. To determine which antibiotic will be effective, it is necessary take your cow's milk for analysis to a specialized veterinary laboratory.

Experts will definitely advise you on something that can really cure the animal. You can treat a cow without a veterinarian, only after receiving detailed instructions from him.

Ways and secrets to increase milk yield

  • The amount of milk obtained during milking directly depends on how and what the cow eats. It is especially important to pay attention to this factor during dry periods and in the first three months after calving.

    It is very important that the diet compiled for the animal gives him a lot of energy, carbohydrates, vitamins and minerals, fats and proteins that can be easily absorbed by the body.

    Thus, in addition to high-quality feed during these periods, it is important to give cows various mineral and vitamin supplements.

  • We have already mentioned how important it is to prepare before milking. Massages and attention to the cow also affect the amount of milk received.
  • It is very important that the cow is healthy. Also, in no case should you expose the animal to stress, since milk yield can drop significantly from such a thing.

Milk quality: discussing positive and negative factors of influence?

The composition and properties of milk can change quite often, and this will not always indicate something bad.

For example, the factors of such differences and changes can be attributed to:

  • The breed of the cow, as well as her age. There are many dairy breeds that produce large amounts of full fat milk. With age, milk yield and quality indicators decrease.
  • The lactation period in which the animal is located.
  • Features of the diet of the cow, as well as the conditions of its maintenance.
  • Productivity level.
  • Features and regularity of milking.

So, during the lactation period, that is, for 300 days, the milk of the same cow can change its properties three times. In particular, immediately after calving, we do not receive milk, but colostrum, which leaves the udder for the first 5-7 days.

For the longest period, we get ordinary milk, which, 10-15 days before calving, is replaced by old-fashioned, bitter taste.

Another very important characteristic of cow's milk is its fat content. Today, experts call the most important criterion for the appearance of high fat content in milk the amount of protein that a cow receives from food.

Also, fat content increases with the age of the cow, although after 6 years it gradually begins to decrease.

Also, in the chemical analysis of the composition of milk, the content of milk sugar is often determined. The taste of milk directly depends on this component. However, it is impossible to influence its change, since milk sugar constantly remains at the same level regardless of the number of years of lactation.

As for the cow's diet, the more you give her feed containing proteins, the fatter the milk will be. Proteins, that is, proteins, will also fall into the composition of milk. Such feeding can also increase milk yield, raising them by 10%.

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The vitamin composition and taste qualities put cow's milk on a pedestal. It is the most popular among the milk of other animals. It is easy to obtain it in large quantities both in the personal economy and on an industrial scale. But often in a herd one cow gives much less milk than another.

Secrets are not only in hereditary factors and physiological abilities of the udder and the body. Also important is the interest of the owner of cattle to carry out a set of measures for milking.

The appearance of milk in a cow is considered a complex physiological process. Nutrients enter the udder, which form the basis of your favorite delicacy. And from the digestive system, nutrients enter the bloodstream.

For example, in order for a cow to give a liter of milk, up to five hundred liters of blood must pass through her udder.

Thus, much depends on the circulatory system, which should work like a clock. Not the last role is played by the hormonal and nervous systems.

The udder is a mammary gland, divided in the middle by a septum. The latter plays the role of a support for the right and left halves. They, in turn, are divided into quarters - front and back. Accordingly, there are four nipples on the udder (rarely up to six). Milk is produced in many small sacs called alveoli. This is just an explanation for the question of where the cow has milk.

From the inside, they are covered with a secretory epithelium that produces milk. The alveoli communicate through tubules with ducts that empty into the milk cistern. It is connected to the nipples.

During lactation, the alveolar system changes. Such a complex process depends on external factors, including mastitis, the difference in productivity and milk composition.

The epithelium connects the leading parts of milk from the nutritional components that come with the blood:

  • proteins;
  • fats;
  • lactose.

During the connection process, all these components change. But vitamins, enzymes, hormones, mineral salts reach the animal's plasma from the blood in kind, as they are. Their content may vary. For example, the composition of calcium in milk is fourteen times higher than in blood plasma. The same can be said about phosphorus, only the number is ten. As for sodium, there is a smaller composition - the difference in favor of plasma is seven times.

During lactation, milk is produced in the udder without interruption:

  1. first it flows into the cavity of the alveoli;
  2. excreted through small ducts into large ones;
  3. tanks are filled.

The whole process takes up to half a day, and then the mammary gland ceases to be so active.

If the cow is not milked for more than sixteen hours, then the pressure in the udder increases and the secretion of milk stops completely.

Not milking a cow even for the specified period means starting the process of absorption of milk components. Allowing skipping leads to a decrease in milk production, the animal simply gives it less. The udder must be large enough not to overflow, the cow must be cooked for this.

Milking

The milking of cattle representatives is a very responsible and complex process, as well as the appearance of milk. The udder filled up. If catheters are placed in the nipples, large streams can be seen. But despite the intensity, less than half of the contents will be milked. A smaller part of a cow's milk before it is milked is in tanks.

There are cases when, at the very beginning of milking, a significant part of the milk was in the tanks. To get the rest, you need to compress the alveoli. It turns out that the first milk portions flow out of the tank quite easily. The cow makes no effort to drain it and cannot even restrain it.

For full return, you need to make an effort to squeeze the alveoli located in the nipples. In this case, join the manual method or with the help of milking equipment. They contain the bulk of the milk produced.

It is never possible to empty the udder completely. There remains a little more than a liter of residual milk. It does not disappear, new arrivals join it, and in a few days the milk is milked out.

If residual milk is considered a natural physiological phenomenon, then sometimes it does not completely empty the udder due to poor milking.

How is milking done?

Milking is considered a reflex. To a certain extent, the rush of blood plays a role in the flow of milk. This is understandable by the increase in the temperature of the udder, it becomes hot, the teats are slightly enlarged.

So the following components of the body are involved in milking:

  • nervous system;
  • endocrine glands (thyroid, posterior pituitary, stellate cells);
  • breast muscles.

If in the laboratory you try to turn off the sensitive receptors of the mammary gland, then the natural process of milking is disturbed. Just touching the nipples is pointless, they need to be carefully squeezed, since it is possible to get to the right receptors by volitional compression.

The greatest impact should be on the base of the nipples. Experienced breeders adapt to the process.

According to the experiments, the specialists managed to prove that uniform squeezing of the nipples a hundred times per minute gives an excellent result.

Of course, this is a laborious process, but the resulting product is worth it.

push hormone

From talking about the number of nipple squeezes during milking, it is worth moving on to the recoil hormone. This is oxytocin. Most of all, it is cultivated in the blood by the third minute from the beginning of the process. After four or five minutes of milking, the hormone becomes inactive.

Therefore, the ability to produce milk is directly related to the ability to use these reflexes.

An experienced mistress or owner of dairy cows should perform all procedures promptly so as not to miss the period of oxytocin action. It is desirable that the milking pattern be the same. Thus, it is possible to achieve continuity and fruitfulness of the milking process.

razdoy

Measures taken for quality feeding, maintenance and milking of calving cows are called milking. If the whole complex is performed correctly, then large milk yields are obtained and the productive health of the animal is maintained.

When the calves appear, you can start the distribution. About two weeks after calving, the cow is milked up to five times a day. Then three times. This is especially true for young females when it is necessary to achieve high milk yields and. Although, for financial reasons, many farms are switching to double milking - in the morning and in the evening, since cost reduction will be required for these purposes.

Previously, it was believed that milk resides during milking. Then this misconception was debunked. It turned out that it is formed constantly. A smaller part of a cow's milk is stored in the glandular cells themselves, a little more - in the alveoli. Only now the last "vessels" accumulate milk, inferior in fat content to another.

It is the last drops of milk that are called cellular and the fattest. In general, the more filled the alveoli, the lower this indicator.

A smaller part of the milk is obtained from cows in the final stage of lactation. The smaller the gap between milkings, the lower the pressure in the udder. But the white nutrient fluid arrives sooner and overall productivity also increases. The short period of storage of milk in the udder contributes to the increase in fat content.

Specialists have developed certain milking rules that should be memorized by all livestock breeders:

  1. udder washing with warm clean water;
  2. udder massage stimulates milk flow. Before milking, first rub the right half, then the left. Then they make several compressions, as if pushing the udder up, as a calf does. Before the process is completed, the udder is massaged again, as if driving milk from the ducts;
  3. milking should take place at the same time, in a constant place;
  4. after the appearance of the first calf, milking should take place up to four times a day at intervals of seven hours. This avoids pressure in the alveoli in a young cow;
  5. observance of the order of cows. In general, developed habits should be observed. The cow is very sensitive to any change;
  6. kind attitude towards the animal, so as not to create stressful situations. During milking, you can not scare her, shout at her or beat her.

Every diligent herd owner or newcomer to the agricultural industry is faced with the problem of choosing an animal. The latter need to remember a few rules that will help you get a good cow that brings good milk yield.

The mammary gland secretes milk continuously. In the intervals between milkings, it fills the capacitive system of the udder: the cavity of the alveoli, the excretory ducts, the milk channels, the milk passages and the cistern. As the system fills up, the pressure rises and, reaching a certain value (40-50 mm Hg), becomes a factor that inhibits milk formation.

The milk in the udder can be conditionally divided into cisternal, alveolar and residual. Cisternal milk can be obtained by inserting a catheter (metal tube) into a pine cistern before milking; alveolar (located in the ducts and alveoli) is released during milking of this pine or other udder teats; residual milk can be extracted by administering large doses of the hormone oxytocin to the animal. During normal milking of an animal, only cisternal and alveolar milk is milked.

The removal of milk from the udder during milking of a cow is a rather complex process, including neuro-hormonal mechanisms. It involves the nervous system, endocrine glands and udder muscles. In order for their interaction to occur, the cow must be prepared for milking: wash and massage the udder. In this case, the nerve endings of the peripapillary region of the udder and nipples are irritated. Excitation along the nerve pathways reaches the spinal cord. From here, one part of the signals is sent to the brain, and the other to the mammary gland. In response to these signals, the posterior pituitary gland secretes the hormone oxytocin, which appears in the blood after 20-30 seconds and reaches the mammary gland with the blood flow, causing contraction of the muscle cells surrounding the alveoli and small tubules. The alveoli seem to be compressed, the tubules shorten, and their lumen increases. Favorable conditions arise for the release of milk into the ducts of the gland. At the same time, the nipple sphincter relaxes.

When the entire mass of the alveoli is reduced, large milk ducts and cisterns are filled with milk, the pressure inside the udder increases sharply (up to 50-70 mm Hg) and the milk ejection reflex occurs.

The hormone oxytocin is released not only when the udder is irritated. The same effect is caused by the sound of the switched on milking machine, the appearance of a milkmaid and mechanical irritation of the teats during milking. A sharp noise, fright, pain or the appearance of a new milkmaid can slow down the milk ejection reflex, apparently, this is due to increased production of the hormone adrenaline in the body.

The hormone acts for a short time, as it is destroyed by its antihormone. The concentration of the hormone in the blood, necessary for milk transfer, is maintained for 6-8 minutes. During this time, the cow needs to be milked quickly.

When preparing a cow for milking, the milk allowance does not occur immediately. It takes a certain time until the moment when the response of the body to irritation occurs. This is the latent period of milk production. Usually this period in cows is 40-50s, although in individual animals, due to individual characteristics, there may be significant deviations. The duration of the latent period of milk production largely depends on the filling of the udder before milking. With strong filling, especially at the beginning of lactation or with long intervals between milkings, it can be 30 seconds, with low milk yield and frequent milkings - more than 1 minute. During lactation, the latent period of milk ejection is significantly lengthened and at the 6-7th month of lactation, as a rule, lasts more than 1 minute.

The process of extracting milk from the udder itself has 3 distinct phases. This is due to the nature of the change in pressure inside the udder under the action of the hormone oxytocin and the milk in the gland. In accordance with the change in pressure inside the udder, the rate of milking also changes, or, as it is also called, the rate of milk ejection.

With machine milking, all these phases of milk flow are clearly visible through the sight glass and the milk hose in the milking machine, and the milkmaid has the opportunity to correctly navigate the process of milking a cow: take additional measures to influence the mammary gland and turn off the milking machine in time.

It is impossible to call the milk ejection reflex for the second time in the same milking. This is due to the temporary non-excitability of the tissues, which occurs after a strong excitation during the period of the previous milking (rest phase). In practical terms, this phenomenon can be observed during the milking of highly productive cows 2-2.5 hours after the main milking. In this case, the rate of milk flow is sharply reduced, and for a more complete extraction of milk from the udder, a long stimulating massage is required during the milking period. However, in this case, up to 40% of milk and 60% of milk fat, which was present in the gland before milking, remains unmilked.

In the first 4 months of lactation, the rate of milk transfer in cows is almost at the same level. With good preparation of animals for milking, it can be more than 2.5-3.0 l/min., with an average value of 1.5-1.8 l/min. However, already at the 6th month, the rate of milk transfer decreases significantly (by an average of 27-38% at intervals between milkings of no more than 12 hours). At the end of lactation, it is almost impossible to induce a full-fledged milk ejection reflex.

Young animals, as a rule, give milk faster and more completely. They also have a much shorter latent period of milk ejection, i.e. the allowance of milk under the action of udder massage occurs earlier than in adult cows. This must be taken into account when organizing the milking process on the farm.

The delay in the start of milking at the onset of the allowance leads to incomplete use of the milk ejection reflex. As a result, a lot of unextracted milk remains in the udder. With frequent repetition, this leads to premature self-starting of cows, as the process of milk formation is disrupted. Violation of the usual milking regimen also contributes to an increase in the amount of residual milk in the udder. All this must be taken into account in practical work.

Milking machines and their device

For machine milking of cows on pastures, there are mobile universal modified milking machines UDS-ZB. These installations consist of two sections of four parallel walk-through milking machines. The UDS-ZB kit also includes a milk pipeline, individual milk meters (UZM-1), devices for circulating washing of the milk line, a filter and a milk cooler, a vacuum unit (UVA-12.000 vacuum pump driven by a UD-25 gasoline engine or in the presence of a power source from the motor). Productivity of the master of machine milking is 25-26 cows per hour.

The most effective use of milking units with a milk pipeline, which, with a yield of 4-6 thousand kg of milk from one cow per year, allows one worker to serve up to 40 goals.

The type of milking unit must be selected based on the fact that the duration of milking should not exceed 2 hours.

It is advisable to use milking units with milk with a wire in a configuration for 100 cows in three versions: ADM-8A-1 of the main version, ADM-8A-1 of version 05 and ADM-8A-1 of version 06. Each of these units consists of a glass milk pipeline and a vacuum - wires installed above the barn stalls. The milking machines of the unit are connected to the milk by a wire and a vacuum wire using combined milk-vacuum taps. In the dairy room inside the barn or next to it, a system for primary milk processing and a system for washing the milk ducts of ADM-8A-1 units of all versions were installed.

The execution of the ADM-8A-1 units is selected depending on the working conditions on the dairy farm. The ADM-8A-1 unit, version 05, is supplied without milk dispensers, a washing machine, a milk cooler, a device for lifting the milk pipeline branches and is the simplest of all three modifications of the ADM-8A-1 unit. The ADM-8A-1 unit of the basic version is complete and provides mechanization and automation of all operations when milking cows.

The operation of the milking unit ADM-8A-1 consists of the following stages:

Preparation of the milking unit for milking;

Preparing the udder of cows for milking;

Installation of milking machines on the teats of the udder;

Milking cows;

Measurement of milk produced from each cow (during control milkings);

Transportation of milk to the dairy department;

Measurement of milk produced from a group of up to 50 cows;

Filtration;

Milk cooling;

Milk supply to the storage tank;

Washing and disinfection of the milking unit.

Units ADM-8A-1 versions 05 and 06 do not perform some of the operations, such as automatic washing, milk cooling through a plate cooler, as this is not provided for by their design. However, ADM-8A-1 units of versions 05 and 06 are much simpler in design and maintenance and are more suitable for conditions farms. If necessary, they can be installed to serve any number of cows on the farm (from 50 to 100) and at the same time mount a milk line and a vacuum line of the required length.

The device and operation of the milking machine

The milking machine is the main working part of the milking machine. With its help, milk is extracted from the cow's udder, then it is sent through milk tubes and hoses to a milking bucket or other container. In addition to the apparatus, the milking machine has a vacuum pump with an engine, a vacuum pipeline and a regulator, and a vacuum gauge.

During the operation of the milking machine, the pump pumps air out of the milking machines through a vacuum pipeline, i.e. creates a vacuum in them. The value of this vacuum is controlled by a vacuum gauge and automatically adjusted to the desired level by a vacuum regulator.

The milking cluster consists of a pulsator, a collector, four teat cups, a milking bucket with a lid, milk and air tubes and hoses. The milking machine usually has eight main and two reserve machines.

Milking machines produced by the domestic industry generally meet the technological requirements of machine milking. Knowledge of machine milking technology allows the operator to ensure the complete and safe milking of animals.

Milking machines for cows are classified:

¨ according to the method of extracting milk from the udder - squeezing and vacuum (suction) devices;

¨ according to the principle of action - three-stroke, two-stroke and continuous excretion of milk;

¨ according to the method of machine milking - devices for simultaneous, pair and quarter milking;

¨ for the collection of milk - devices with the collection of milk in portable or hanging milking buckets, as well as through a milk pipeline into a collection tank.

The set of milking machines includes: pulsators that automatically regulate the change in vacuum and atmospheric pressure; collectors designed to collect milk from teat cups and create a rest cycle in three-stroke machines; milking cups; milking buckets with lids; dairy and vacuum taps; hoses, pipes and other details.

All milking machines operate under the action of vacuum pressure, which is provided by a vacuum installation. The vacuum unit has an electrically driven vacuum pump and a control panel.

In modern designs of milking machines, two-chamber teat cups are used (Fig. 4.), which include a body and teat rubber. An interwall chamber is provided between the body and the teat rubber, and when the cup is connected to the teat of a quarter of the udder, a teat chamber is formed.

In two-stroke milking machines, the working cycle consists of sucking and compressing cycles, and in three-stroke milking machines, an additional rest cycle is added.

Tact - a period of time of physiologically homogeneous impact of the milking machine on the udder of the animal. The cycle of the working process of machine milking is a period of time during which a set of differently named cycles is performed.

During the sucking stroke, vacuum pressure is created in both chambers of the teat cup, and milk is extracted from the teat due to the pressure difference in the udder and the teat chamber. At the compression stroke, the vacuum pressure is maintained in the teat cup pod, and the pressure in the interwall chamber rises to atmospheric pressure due to the supply of air into it. Under the action of the pressure difference created in the chambers of the teat cup, the teat rubber is compressed and massages the teat, stopping the extraction of milk. During the operation of two-stroke milking machines, there is no phase in the working cycle for the teat to rest from the vacuum effect on it.

For milking, "Volga", ADU-1, LDS, etc. are used. All of them have design differences and their own characteristics during operation, but the same name and purpose of the nodes.

Sucking Squeeze Sucking Squeeze Rest

Rice. 4 Scheme of operation of two-chamber teat cups

a - in two-stroke milking machines;

b - in three-stroke milking machines;

1 - milk pipe; 2 - viewing cone; 3 - connecting ring; 4 - sealing ring; 5 - body; 6 - suction chamber

The pulsator is designed to convert the constant vacuum received from the pump into an alternating or pulsating one, and to transfer it to the collector.

The manifold is designed to connect milking cups, distribute alternating vacuum over them, collect milk from individual cups and transport it through a milk hose to a container. In addition, the collector of the three-stroke apparatus provides a rest cycle. Together with the cups, it forms the hanging part of the milking machine, which is held by vacuum on the udder of the animal during operation.

The milking bucket is designed to collect milk and place the rest of the machine in it during operation or transportation.

The milking cup is the main working body of the milking machine, which acts directly on the udder of the animal. It consists of a body, liner, metal ring and milk tube.

Vacuum pump - creates a constant vacuum in the vacuum line. From the vacuum line through the vacuum cock and air hose, the vacuum is distributed to the pulsator and simultaneously to the milking bucket.

Milk flows from the collector through the milk hose to the milking bucket. There is a so-called sucking cycle.

To protect the udder from the undesirable consequences of the action of a two-stroke apparatus, new modifications of the ADU-1 type apparatus use a more complex pulsator, the so-called vibropulsator. It allows you to soften the effect of the vacuum on the udder and, in addition, stimulate the milk ejection reflex in the animal.

Two-stroke milking machines hold better on the teats, are simpler in design and milk cows faster, but they require higher qualifications of milkmaids and very strict adherence to machine milking rules. When milking with a two-stroke machine, in no case should you put milking cups on the teats if the cow has not allowed milk, and leave them on the teats after the milk flow has stopped, as this leads to udder disease.

Machine milking technique

Compared to manual milking, machine milking facilitates the work of operators and increases their productivity. The process of machine milking accounts for about 50% of the total cost of cow maintenance. The technology of machine milking is determined by the physiology of the animal.

Before machine milking, it is obligatory to carry out pre-milking preparation of the udder, which includes washing the udder with warm water, rubbing it and massaging it, milking the first streams of milk, turning on the milking machine and connecting it to the animal's udder. Pre-milk preparation of the udder should be carried out within 45 - 60 seconds. The main operation is to obtain milk from the udder using a milking machine, which must be completed in 4-6 minutes at a milking intensity of 2 3 dm 3 /min. The milking machine should be connected to the udder of animals after the onset of the milk ejection reflex. Machine milking should be carried out without the use of manual milking. Final operations - turning off the milking machine and removing the teat cups from the udder, disinfecting the udder. Overexposure of teat cups on udder quarters should be avoided.

The technique of milking cows on modern milking machines requires certain knowledge and high professional skills. Improper use of the milking machine can not only disrupt the milking process, but also cause a serious illness in the animal's udder, so milking is carried out according to a certain technology, which includes preparing cows for milking, connecting the machine, milking, final udder massage, machine milking and turning off the machine.

Preparing cows for milking: coming to workplace, the milker should place the milking bucket close to the front legs of the cow. Check the pulsation frequency of the device and, if necessary, adjust. Check the operation of the teat cups and the collector, the tightness of the lid suction. After making sure that the device is working correctly, proceed to the preparation of the udder.

Wash the udder with warm water (40…50°C) and wipe it with an individual napkin or a clean towel moistened with a disinfectant solution. This can be a 0.5% solution of iodine monochloride (50 g per 10 liters of water), desmol (50 g of powder per 10 liters of water) or sodium hypochlorite (0.5 liters of stock solution per 10 liters of water).

If the milk ejection reflex does not occur after performing these operations, then the udder is quickly massaged. To do this, they wrap their fingers around individual quarters of the udder and stroke them from top to bottom in the direction of the nipples.

Then the first streams of milk (2 - 3 drops from each nipple) are poured into a control mug, preferably black. It should have a strainer or a dark cloth that allows the milk to pass through, then the most contaminated portions of the milk are removed. In addition, this makes it possible to detect udder disease in a timely manner and take measures to prevent the spread of the disease.

The preparation of the udder for milking is carried out in two ways:

1. The udder is washed and wiped, while massaging it with direct movements from the milk mirror to the front nipples. They also wash and wipe the udder on the side. Then, with an unfolded towel, wipe the nipples, starting with those farthest from the milkmaid. The preparation of the udder ends by pushing the teats from the bottom up, as a calf does when suckling.

2. With an unfolded towel, they wrap around the bottom of the udder lobes remote from the milkmaid, then the near ones, washing them with a simultaneous massage, wipe the nipples with a dry towel. This technique ends, like the first one, by pushing the nipples from the bottom up.

The duration of both receptions is 30-45 s. After washing every 4-5 cows, the water in the bucket is changed.

Connecting the machine: udder preparation usually lasts about one minute; during this time, the cow should start milking, and the milkmaid should quickly connect the milking machine. Hold the collector with one hand so that the glasses hang freely. When the udder is low, grab the milk tubes in your hand, open the milk hose clamp. Take one of the glasses with your free hand and set it vertically with the head up, the milk tube should be bent at the same time, and the thumb and forefinger should be free. With a quick movement, lift the glass up to the nipple and guide the nipple into the glass with two free fingers. Using the same methods, alternately put on the remaining milking cups. When putting on glasses, prolonged air suction is unacceptable.

Rules for obtaining pure milk with the lowest bacterial contamination

1. Clean the barnyard (remove manure and change bedding 2 times a day) in the morning and in the evening.

2. Clean cows daily. Wash off contaminated places and dried manure from the skin of cows with warm water (25 ... 30 ° C). Cut long hair near the legs, sides and on the udder itself short.

3. Timely remove manure.

4. Cleaning the barnyard and cows, changing bedding, as well as harvesting and distributing feed should be stopped 1 hour before the start of milking.

5. Before each milking, thoroughly wash the udder and teats of the cow with clean warm water (40 ... 45 ° C) from a sprayer or bucket, wipe dry with a clean towel and massage. Washing the udders from a common bucket with the same water, followed by wiping with the same towel, contributes to the contamination of milk and the appearance of udder diseases.

6. Before milking, tie the tail of the cow to the leg with soft twine or a special tail holder.

7. Before milking, wipe the sides and belly of the cow with a wet cloth to remove dust and wool and prevent them from getting into the milk. After each use, rinse the cloth in a disinfectant solution.

8. Use pails with a partially closed top.

9. Milk cows with dry hands. Do not wet your hands with milk during milking. Milk the first streams of milk into a separate promise and do not drain into the general milk yield.

10. If during milking blood, pus or curdled clots are released, then this milk must be drained into a separate container and immediately reported to the veterinary staff. Use milk from a sick cow only with the permission of the veterinary supervision.

11. When milking cows on a pasture, choose a place for a camping site that is high, dry, with a slope, and arrange a platform for milking with a wooden floor and a canopy.

Rules for personal hygiene of farm workers

1. Machine milking of cows and work with animals is allowed for persons who have undergone special training and instructed in safety techniques.

2. Milkmaids and other farm workers who are in direct contact with milk are allowed to work only after a medical examination, and in the future, must regularly undergo medical checkup, to have personal sanitary books.

3. Before starting milking, the milkmaid must put on a clean dressing gown and scarf

4. The hands of the milkmaid and workers must be clean, with short-cut nails.

Primary processing and processing of milk

According to the state standard, milk at milk collection points is accepted as 1st or 2nd grade. Primary processing and processing of milk is carried out in strict accordance with the requirements of sanitary and veterinary rules for dairy farms.

Primary milk processing is a set of technological operations aimed at improving the quality of milk without changing its original properties. The primary processing of milk includes the following technological operations: filtration, centrifugal cleaning, cooling, storage and accounting.

Requirements for the quality of milk

Milk is a highly valuable product containing all the nutrients necessary for the body. The safety and quality of milk depend on its temperature: at elevated temperatures, it quickly deteriorates and loses nutrients. The cooling temperature of milk and the time elapsed after the completion of milking are important criteria for its quality. So, freshly milked milk in accordance with GOST 13264-70 “Cow's milk. Harvesting Requirements” should contain no more than 500,000 microbial bodies.

Immune bodies and bactericidal substances present in fresh milk delay the development of bacteria for several hours (the phase of bactericidal action). With a decrease in milk temperature, the number of bacteria decreases, and the phase of bactericidal action increases from 2-3 hours (at 36°C) to 19-36 hours (at 8...12°C), with deeper cooling (0...4°C) the period of the phase is extended to several days. The bactericidal properties of milk, depending on the cooling temperature, are as follows:

Thus, the faster the milk is cooled, the higher the quality of the dairy product will be.

Milk intended for the production of rennet cheeses must meet the requirements of the highest or I grade, but contain no more than 500 thousand/cm 3 somatic cells and, according to the rennet-fermentation test, meet the requirements of at least class 2. The content of spores of mesophilic anaerobic lactate-fermenting bacteria in such milk should be no more than 13 in 1 cm 3 (for cheeses with a high temperature of the second heating and no more than 2 in 1 cm 3).

Milk must be obtained from healthy animals, and the quality must comply with GOST 13264-88 “Cow's milk. Purchasing requirements.

Not later than 2 hours after milking, the milk is filtered (cleaned) and cooled to a temperature not higher than 6 C 0

Milk should be natural, white or slightly creamy in color, without sediment and flakes. Freezing is not allowed. Milk should not contain inhibitory (antibiotics, detergent-disinfectants, formalin) and neutralizing substances (soda, ammonia).

The milk quality determined by the standard is given in table 8 on the next page.

Table 8

Milk quality as defined by the standard

Level of quality The norm of quality indicators for varieties
Supreme I II
Smell and taste Peculiar to milk (without foreign smells and tastes) A slightly pronounced fodder smell and taste is allowed in the winter - spring period of the year.
Acidity, 0 T 16 – 18 16 – 18 16 – 20
Degree of purity according to the standard, not lower than the group I I II
Bacterial contamination, thousand / cm 3 up to 200 300 – 500 500 – 4000
The content of somatic cells, thousand / cm 3 no more 500 1000 1000

Milk cleaners and milk storage containers

On milking machines of a unified series with a milk line, milk is cleaned using a fabric milk filter of the ADM type.

Milk filter ADM. 09.000 is designed to purify milk from mechanical impurities and consists of a body made of stainless steel, a guide with a wire frame, two adapters with nuts and a reusable filter element. Until 1987, milk filters were equipped with lavsan filter elements. Currently, the filter material is a non-woven needle-punched two-layer fabric, the outer layer of which is made more loose and is made of lavsan, the inner layer is made of polypropylene. The latter is melted during the fabrication process, which makes its pores even smaller. During the filtration process, milk passes through two stages of purification in one pass.

If the lavsan filter provides nominal cleaning within 100 microns, then the new filter element - within 56 microns.

Cooling of milk at milking machines with a milk pipeline is carried out using a plate cooler OM-1500, which is connected to a refrigeration unit or to a cold water pipeline. Such equipment is included in the set of the corresponding milking installation and is located in the dairy farm.

When using installations with milking buckets, as well as for better cleaning and cooling of milk in a farm dairy, a flow process line (PTL) is created, which includes an OM-1A milk cleaner-cooler, a water-cooling unit, and a container for collecting and storing milk.

Milk cleaner-cooler OM-1L is designed for centrifugal cleaning and cooling of milk on dairy farms. OM-1A in the technological scheme of the milking machine completes the line of milking and primary processing of milk. Cleaner-cooler OM-1A (Fig. 5.) consists of a centrifuge, a plate-type milk cooler mounted on a stove, as well as hoses for supplying milk and supplying purified milk to the cooler. In the conditions of farms and complexes, cooling tanks and thermos tanks are used to cool milk. There are cooling tanks with intermediate and direct cooling.


Rice. 5 Milk cleaner-cooler OM-1A

1 - electric motor; 2 - bed with a drive mechanism; 3 - centrifuge; 4-6 - hoses; 7 - milk cooler; 8- tee; 9 - milk receiver; 10 - milking machine filter housing

Cooling tanks with an intermediate coolant (chilled water) include TOM-2A, RPO-1.6, RPO-2.5, etc. Tanks with direct cooling are MKA-2000L-2A.

Cooling tank RPO-1.6 is designed for cooling milk on farms. It consists of a milk bath, which is closed from above with rectangular lids with hatches. From below, the milk bath has a cooling jacket, which is formed by the wall of the bath and the base of the tank. Outside, the cooling tank is covered with thermal insulation and a casing. In the middle part of the bath there is an electric paddle mixer and a thermometer. At the end of the bath there is a measuring ruler graduated in liters.

Cooled water (refrigerant) flows by gravity from the water-cooling unit AB-30 (THU-14) into the cooling jacket and circulates through it, providing good heat transfer. Water is pumped out of the cooling jacket of the cooler

Table 9

Specifications of milk cooling equipment

Brand of machines, installations and equipment Working capacity, m 3 (throughput, l / h) Milk cooling time from 36 to 4 °С, h Installation weight, kg
Milk cleaner-cooler OM-1A (1200-2500) - 180
Cooling tanks with intercooling: 1,6 1,75 400
Cooling tank MKA-2000L-2A with direct cooling 2,0 3,0 620
Milk cooling tanks: 0,15 3,5 120
Milk cooling and storage plants: 0,3 - -