The process of extracting milk from a cow 6. Physiology of milk excretion during milking. Methods and secrets of increasing milk yield
Milking machines and their design
For machine milking cows on pastures, there are mobile universal modified milking units UDS-ZB. These installations consist of two sections of four parallel passage milking machines. The UDS-ZB set also includes a milk pipeline, individual milk meters (UZM-1), devices for circulation washing of the milk line, a filter and milk cooler, a vacuum unit (vacuum pump UVA-12.000 driven by a UD-25 gasoline engine or if there is a source of electricity from an electric motor). The productivity of a machine milking master is 25-26 cows per hour.
The most effective use of milking units with a milk pipeline, which, with a milk yield of 4 - 6 thousand kg of milk from one cow per year, allows one worker to serve up to 40 heads.
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 a milk wire in a configuration for 100 cows in three versions: ADM-8A-1 basic version, ADM-8A-1 version 05 and ADM-8A-1 version 06. Each of these units consists of a glass milk line and a vacuum -wires installed above the barn stalls. The milking machines of the unit are connected to a milk 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-conducting paths of ADM-8A-1 units of all versions are installed.
The design 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, and a device for lifting milk pipeline branches and is the simplest of all three modifications of the ADM-8A-1 unit. The basic version of the ADM-8A-1 unit is complete and provides mechanization and automation of all operations when milking cows.
The operation of the ADM-8A-1 milking unit consists of the following stages:
Preparing the milking unit for milking;
Preparing the udder of cows for milking;
Installation of milking machines on udder teats;
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;
Supplying milk to the storage tank;
Washing and disinfection of the milking unit.
ADM-8A-1 units of versions 05 and 06 do not perform some operations, for example, automatic washing, cooling of milk through a plate cooler, since 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 farm conditions. If necessary, they can be installed to serve any number of cows on the farm (from 50 to 100) and at the same time install a milk line and a vacuum line of the required length.
Design 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 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 a motor, a vacuum pipeline and regulator, and a vacuum gauge.
During 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 amount of this vacuum is monitored by a vacuum gauge and automatically adjusted to the desired level by a vacuum regulator.
The milking machine consists of a pulsator, a collector, four teat cups, a milking bucket with a lid, milk and air tubes and hoses. A milking machine usually has eight main and two reserve units.
Milking machines produced by the domestic industry generally comply with the technological requirements of machine milking. Knowledge of machine milking technology allows the operator to ensure 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 operating principle - three-stroke, two-stroke and continuous milk removal;
¨ according to the method of machine milking - simultaneous, pair and quarter milking machines;
¨ for milk collection - devices that collect milk into portable or hanging milking buckets, as well as through a milk line into a collection container.
The set of milking machines includes: pulsators, which automatically regulate the change in vacuum and atmospheric pressure; collectors designed to collect milk from teat cups and create a rest stroke in three-stroke machines; milking cups; milking buckets with lids; milk and vacuum taps; hoses, tubes and other parts.
All milking machines operate under the influence of vacuum pressure, which is provided by a vacuum installation. The vacuum unit has an electrically driven vacuum pump and a control panel.
Modern designs of milking machines use two-chamber milking cups (Fig. 4), which include a body and teat rubber. An inter-wall chamber is provided between the body and the teat rubber, and when a glass is connected to the nipple of the udder quarter, a sub-mammary chamber is formed.
In two-stroke milking machines, the working cycle consists of sucking and squeezing strokes, while in three-stroke milking machines a rest stroke is additionally added.
Tact is a period of time of physiologically homogeneous impact of the milking machine on the animal's udder. The cycle of the working process of machine milking is a period of time during which a set of different 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 difference in pressure in the udder and the teat chamber. During the compression stroke, vacuum pressure is maintained in the teat chamber of the teat cup, and in the interwall chamber the pressure increases to atmospheric pressure due to the supply of air into it. Under the influence of the pressure difference created in the chambers of the teat cup, the teat rubber compresses and massages the nipple, stopping the extraction of milk. When operating push-pull milking machines, there is no phase in the working cycle for resting the teat from the vacuum effect on it.
For milking, “Volga”, ADU-1, LDS, etc. are used. They all have design differences and their own characteristics during operation, but the name and purpose of the units are the same.
Sucking Squeeze Sucking Squeeze Rest
Rice. 4 Scheme of operation of two-chamber teat cups
a - in push-pull 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 alternating, or pulsating, and to transfer it to the collector.
The collector is designed to connect milking cups, distribute alternating vacuum over them, collect milk from individual cups and transport it through a milk hose into a container. In addition, the manifold of a three-stroke apparatus provides a rest stroke. Together with the glasses, it forms the suspended part of the milking machine, which during operation is held by a vacuum on the animal's udder.
The milking bucket is designed to collect milk and place other components of the machine in it during operation or transportation.
The milking cup is the main working part of the milking machine, acting directly on the animal's udder. It consists of a body, nipple rubber, metal ring and milk tube.
Vacuum pump - creates a constant vacuum in the vacuum line. From the vacuum line, through the vacuum tap and air hose, the vacuum is distributed into the pulsator and at the same time into the milking bucket.
From the collector, milk flows through the milk hose into the milking bucket. There is a so-called sucking cycle.
To protect the udder from the undesirable consequences of the action of a push-pull device, new modifications of devices such as ADU-1 use a more complex pulsator, the so-called vibrating pulsator. It allows you to soften the effect of the vacuum on the udder and, in addition, stimulate the milk release reflex in the animal.
Push-pull milking machines hold the teats better, are simpler in design and milk cows faster, but they require more highly qualified milkmaids and very strict adherence to the rules of machine milking. When milking with a push-pull machine, in no case should you put milking cups on the nipples if the cow has not let in milk, and leave them on the nipples after milk production has stopped, as this leads to udder disease.
Machine milking technique
Compared to manual milking, machine milking makes the work of operators easier and increases productivity. The process of machine milking takes up about 50% of the total cost of servicing cows. The technology of machine milking is determined by the physiology of the animal.
Before machine milking, pre-milking preparation of the udder must be carried out, which includes washing the udder with warm water, wiping it and massaging it, milking the first streams of milk, turning on the milking machine and connecting it to the animal’s udder. Pre-milking preparation of the udder should be carried out within 45 - 60 s. The main operation is obtaining 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 skill. Improper use of a milking machine can not only disrupt the milking process, but also cause a serious disease in the animal’s udder, so milking is carried out using 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: upon arrival workplace, the milker should place the milking bucket closer 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 collector, and the suction tightness of the lid. After making sure that the device is working correctly, begin preparing 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 l of water), dezmol (50 g of powder per 10 l of water) or sodium hypochloride (0.5 l of a basic solution per 10 l of water).
If the milk release reflex does not occur after performing these operations, then quickly massage the udder. To do this, wrap your fingers around individual quarters of the udder and stroke them from top to bottom in the direction of the nipples.
Then pour the first streams of milk (2-3 drops from each nipple) into a control mug, preferably black. There should be a strainer or dark cloth in it that allows the milk to pass through, then the most contaminated portions of the milk are removed. In addition, this makes it possible to promptly detect udder disease and take measures to prevent the spread of the disease.
Preparing the udder for milking is done 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 side of the udder. Then the nipples are wiped with an unfolded towel, 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 unrolled towel, first grasp the lobes of the udder that are distant from the milkmaid from below, then the closest lobes, washing them with a simultaneous massage, wipe the nipples with a dry towel. This technique ends, like the first, by pushing the nipples from bottom to top.
The duration of both receptions is 30-45 s. After washing every 4-5 cows, the water in the bucket is changed.
Connecting the device: preparing the udder usually lasts about one minute; During this time, the cow should let out milk, and the milkmaid should quickly connect the milking machine. Hold the collector with one hand so that the glasses hang freely. If the udder is low, grab the milk tubes in your hand and open the milk hose clamp. Take one of the glasses with your free hand and place it vertically with the head up, the milk tube should be bent, and the thumb and index fingers should be free. With a quick movement, lift the glass up to the nipple and use two free fingers to guide the nipple into the glass. Using the same techniques, put on the remaining milking cups one by one. When putting glasses on, prolonged air leaks are unacceptable.
Rules for obtaining pure milk with the least bacterial contamination
1. Clean the barnyard (remove manure and change bedding 2 times a day) in the morning and evening.
2. Clean cows daily. Wash off contaminated areas and dried manure from the skin of cows with warm water (25...30 o C). Long hair around the legs, on the sides and on the udder itself should be cut short.
3. Remove manure in a timely manner.
4. Stop cleaning the barnyard and cows, changing bedding, as well as preparing and distributing feed 1 hour before the start of milking.
5. Before each milking, thoroughly wash the cow’s udder and teats with clean warm water (40...45 o C) from a sprinkler or bucket, wipe dry with a clean towel and massage. Washing the udder from a common bucket with the same water and then wiping it with the same towel contributes to milk contamination and the appearance of udder diseases.
6. Before milking, tie the cow’s tail 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 rag to remove dust and hair and prevent them from getting into the milk. After each use, rinse the rag in a disinfectant solution.
8. Use milk pans 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 bowl and do not pour them into the general milk supply.
10. If blood, pus or curdled clots are released during milking, this milk must be poured into a separate container and immediately reported to veterinary personnel. Use milk from a sick cow only with permission from veterinary supervision.
11. When milking cows on a pasture, choose a place for a camp that is high, dry, with a slope, and arrange a platform for milking with a wooden floor and a canopy.
Personal hygiene rules for farm workers
1. Persons who have undergone special training and instructions on safe techniques are allowed to machine milk cows and work with animals.
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 undergo regular medical checkup, have personal health records.
3. Before starting milking, the milkmaid must put on a clean robe and headscarf.
4. The hands of the milkmaid and workers should 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 regulations 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: filtering, centrifugal cleaning, cooling, storage and accounting.
Requirements for milk quality
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 temperature at which the milk is cooled and the time elapsed after milking is completed are important criteria for its quality. Thus, freshly milked milk in accordance with GOST 13264-70 “Cow's milk. Requirements for procurement" should contain no more than 500 thousand microbial bodies.
Immune bodies and bactericidal substances present in fresh milk delay the development of bacteria for several hours (bactericidal phase). When the milk temperature decreases, the number of bacteria decreases, and the bactericidal action phase increases from 2 – 3 (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.
Milk intended for the production of rennet cheeses must meet the requirements of the highest or 1st grade, but contain no more than 500 thousand somatic cells/cm 3 and, according to the rennet-fermentation test, meet the requirements of at least 2nd grade. The content of spores of mesophilic anaerobic lactate-fermenting bacteria in such milk should be no more than 13 in 1 cm3 (for cheeses with a high temperature of the second heating and no more than 2 in 1 cm3).
Milk must be obtained from healthy animals, and its quality must comply with GOST 13264-88 “Cow's milk. Procurement requirements."
No later than 2 hours after milking, the milk is filtered (cleaned) and cooled to a temperature not exceeding 6 C 0
The milk should be natural, white or slightly creamy in color, without sediment or flakes. Freezing it is not allowed. Milk should not contain inhibitory substances (antibiotics, detergents and disinfectants, formaldehyde) and neutralizing substances (soda, ammonia).
The quality of milk determined by the standard is given in Table 8 on the next page.
Table 8
Milk quality determined by standard
| Level of quality | Standard quality indicators for varieties | ||
| Higher | I | II | |
| Smell and taste | Characteristic of milk (without foreign odors and tastes) | A weakly expressed 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 group | I | I | II |
| Bacterial contamination, thousand/cm3 | Up to 200 | 300 – 500 | 500 – 4000 |
| Content of somatic cells, thousand/cm 3 no more | 500 | 1000 | 1000 |
Milk coolers and milk storage containers
On milking machines of a unified series with a milk line, milk is purified using a fabric milk filter of the ADM type.
ADM milk filter. 09.000 is designed for cleaning 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 Mylar filter elements. Currently, the filter material is a non-woven needle-punched two-layer fabric, the outer layer of which is looser and made of lavsan, the inner layer is made of polypropylene. The latter is melted during the manufacturing process of the canvas, which makes its pores even smaller. During the filtration process, milk goes 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 in milking units 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 supply. Such equipment is included in the package of the corresponding milking installation and is located on the premises of the dairy farm.
When using installations with milking buckets, as well as for better cleaning and cooling of milk, a continuous technological line (PTL) is created in the farm dairy, which includes an OM-1A milk purifier-cooler, a water cooling unit, and a container for collecting and storing milk.
Milk purifier-cooler OM-1L is designed for centrifugal cleaning and cooling of milk on dairy farms. OM-1A in the technological scheme of the milking plant completes the line of milking and primary milk processing. The OM-1A purifier-cooler (Fig. 5.) consists of a centrifuge, a plate milk cooler mounted on a plate, as well as hoses for supplying milk and supplying purified milk to the cooler. In 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 purifier-cooler OM-1A
1 - electric motor; 2 - frame with drive mechanism; 3 - centrifuge; 4-6 - hoses; 7 - milk cooler; 8- tee; 9 - milk receiver; 10 - milking machine filter housing
Cooling tanks with 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 on top with rectangular lids with hatches. The milk bath has a cooling jacket at the bottom, which is formed by the wall of the bath and the base of the tank. The outside of the cooling tank is covered with thermal insulation and a casing. An electric milk stirrer and a thermometer are installed in the middle part of the bath. At the end of the bath there is a measuring ruler, graduated in liters.
Cooled water (coolant) flows by gravity from the water-cooling unit AB-30 (ТХУ-14) into the cooling jacket and circulates through it, ensuring good heat exchange. Water is pumped out from the cooling jacket of the cooler
Table 9
Technical characteristics of milk cooling equipment
| Brand of machines, installations and equipment | Working capacity, m 3 (throughput, l/h) | Milk cooling time from 36 to 4 °C, h | Installation weight, kg |
| Milk purifier-cooler OM-1A | (1200-2500) | - | 180 |
| Intercooled Cooling Tanks: | 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 |
| Installations for cooling and storing milk: | 0,3 | - | - |
The mammary gland secretes milk continuously. In the intervals between milkings, it fills the capacitive system of the udder: the cavity of the alveoli, excretory ducts, milk canals, milk ducts and the cistern. As the system fills, the pressure increases and, reaching a certain value (40-50 mm Hg), becomes a factor inhibiting milk formation.
Milk in the udder can be divided into cisternal, alveolar and residual milk. Cisternal milk can be obtained by inserting a catheter (metal tube) into the cisternal pine before milking; alveolar (located in the ducts and alveoli) is secreted when milking this pine or other teats of the udder; residual milk can be extracted by injecting the animal with large doses of the hormone oxytocin. 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, involving 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: the udder must be washed and massaged. In this case, the nerve endings of the areola area 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 lobe of the pituitary gland secretes the hormone oxytocin, which after 20-30 seconds appears in the blood and reaches the mammary gland through the bloodstream, causing contraction of the muscle cells surrounding the alveoli and small tubules. The alveoli seem to be compressed, the tubules are shortened, and their lumen increases. Favorable conditions arise for milk to exit into the gland ducts. At the same time, the nipple sphincter relaxes.
When the entire mass of the alveoli contracts, 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 milking machine being turned on, the appearance of a milkmaid and mechanical irritation of the nipples during milking. A sharp noise, fear, pain or the appearance of a new milkmaid can slow down the milk release 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 required for milk production is maintained for 6-8 minutes. During this time, the cow needs to be milked quickly.
When preparing a cow for milking, milk supply does not occur immediately. A certain time passes until the body’s response to irritation occurs. This is the hidden period of milk production. Typically, this period for cows is 40-50s, although individual animals may have significant deviations due to individual characteristics. 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 breaks between milkings, it can be 30 seconds; with low milk yield and frequent milkings, it can exceed 1 minute. During lactation, the latent period of milk production lengthens significantly and in the 6-7th month of lactation, as a rule, lasts more than 1 minute.
The process of milk extraction from the udder itself has 3 clearly demarcated phases. This is due to the nature of the change in pressure inside the udder under the influence of the hormone oxytocin and milk found in the gland. In accordance with the change in pressure inside the udder, the milking speed, or, as it is also called, the milk yield rate, also changes.
During machine milking, all of the indicated phases of milk production are clearly visible through the sight glass and milk hose in the milking machine, and the milkmaid has the opportunity to correctly navigate the process of milking the cow: take additional measures to influence the mammary gland and turn off the milking machine in time.
It is impossible to evoke the milk ejection reflex a second time during the same milking. This is due to the temporary non-excitability of tissues that occurs after strong excitement during the period of previous milking (resting phase). In practical conditions, this phenomenon can be observed during milking of highly productive cows 2-2.5 hours after the main milking. In this case, the rate of milk production decreases sharply, and for a more complete extraction of milk from the udder, a long stimulating massage is required during the milking period. However, even in this case, up to 40% of the milk and 60% of the milk fat that was present in the gland before milking remains unmilked.
In the first 4 months of lactation, the rate of milk production in cows is almost at the same level. If animals are well prepared 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 in the 6th month the rate of milk production 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 evoke a full milk letdown reflex.
Young animals, as a rule, give milk faster and more fully. They have a much shorter latent period of milk production, i.e. The release of milk under the influence of udder massage occurs earlier than in adult cows. This must be taken into account when organizing the milking process on the farm.
A delay in the start of milking when allowance occurs leads to incomplete use of the milk ejection reflex. As a result, a lot of unmilked milk remains in the udder. If repeated frequently, this leads to premature self-starting of cows, as the process of milk formation is disrupted. Disruption of the usual milking routine also contributes to an increase in the amount of residual milk in the udder. All this must be taken into account in practical work.
Keeping a cow in the household is very profitable, 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 a simple matter, but the amount of milk and the general condition of the cow’s body greatly depend on the milking technique.
It is important not only to adapt to the animal’s temperament, but also to the characteristics of its udder, the amount of milk that the cow is able to produce.
Naturally, experienced milkmaids also know various ways to increase milk yield and the quality of the resulting milk, which we will be happy to share with you in the article below.
We prepare not only ourselves, but also prepare the cow for the milking process
Before you begin the process of milking a cow, it is very important to take care of hygiene.
First of all, you should clean the stall - fresh manure must be removed, instead of it, fresh and always dry straw is laid (sawdust can also be used).
Secondly, it is important that the barn is ventilated before doing this. In the summer, when there are a lot of different insects, it is very important to close the door to the barn before and during milking. This will slightly reduce the activity of flies, and the cow will not fan herself so intensely with her tail.
Tying the tail also helps, although this will not relieve the animal of nervous tension.
It is best to tie young and temperamental cows, as they can knock out the milk bucket and spill the milk on the ground, or, at best, throw garbage into it. But still, the cow quickly gets used to such a process, and over time she will get used to standing in a position convenient for milking at the same time and behaving obediently throughout this entire process.
Experienced milkmaids advise treating the animal very gently, trying to maintain a “friendly” relationship with it.
To relieve the cow of tension, before milking it is recommended to pet her, call her by name and pamper her with some delicacy. The fact is that a cow is capable of remembering its owner very well, 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 whom 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.
It is better to use warm water to wash the udder so as not to irritate the cow. Afterwards, the udder is wiped dry.
To stimulate the cow's milk supply, it is important perform a preliminary udder massage. It should include light rubbing and patting, not only on the nipples, but also on the entire udder. Thanks to this, your cow will develop a milk ejection reflex, and the flow of milk to the nipples will increase significantly.
Features of the milking process: main techniques and practical tips
It is most convenient to milk a cow while sitting on a low bench, because the more milk the cow gives, the longer the milking process will be.
To collect milk, you need to take some kind of container - an enamel bucket or a special milker. Please note that after each milking, the vessel used for milk will need to be washed and dried. After the cow is 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 nipples when milking - either just with two fingers, or with a whole fist. Although finger milking is a more convenient method 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 nipple, you need to clasp it with all your fingers, that is, with your fist. To avoid chafing the skin of your hands and the skin of your cow's nipples, rub your hands and lubricate them with oil before milking.
Description of the technique of milking a cow
The cow must be milked with both hands at the same time. The two front teats are milked first, followed by the two rear ones. The bucket is placed on the floor under the udder; it can also be clamped with your feet so that it does not accidentally tip over or be knocked out by the cow.
We carry out milking:
- Grasp the nipples with both hands and apply pressure with all your fingers. The hand remains motionless, but with our fingers we pull a little downwards, as if pulling back the nipple.
A stream of milk should run from the nipple, hitting the milking cup, unclench your fingers a little and clasp the nipple again, repeat the described action. The main thing is not to tug your nipples too hard or sharply.
- Usually the first two streams of milk are expressed into a separate cup. Based on the condition of the milk received, it is determined whether the animal has any diseases.
Also, with the first milk, dirt comes out of the nipples.
- It is imperative to adhere to the order of milking, when the front teats are milked first, and then the rear ones. It is necessary to move from one to another as the streams of milk become depleted.
- You can periodically massage the udder so that new portions of milk begin to flow to the nipples.
It is especially important to massage before finishing milking, then the milk will be more fatty.
- Upon completion of milking, it is important to wipe the teats dry, and then lubricate them with some greasy substance - Vaseline or butter. This will protect your nipples from cracking during the hot season.
How often should milking be done: getting to know different options and opinions
Most often, a cow is milked three times a day.
However, some farms in which animals are grazed around the clock and no additional feed other than grass is used to feed the cows, one-time milking is practiced.
But this is done solely for economic reasons, and also because in such conditions cows usually produce a small amount of milk.
But still, if a cow is capable of producing a large amount of milk, then one-time milking will in no case suit her. But in the future, the opinions of both milkmaids and other specialists differ greatly.
Some believe that milking three times a day 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 switches to twice a day, then in this case a drop in milk yield is more likely.
Therefore, this issue should be approached based on your own capabilities. If it is not difficult for you and you have enough time to milk your pet three times a day, do it three times.
If you are too busy during the daytime, and it is more convenient for you to milk only in the morning and evening, you will have to give preference to twice-daily milking.
Is it important to consider when a cow is milked and how does this affect the amount of milk?
The time for milking should always be approximately the same.
Firstly, with 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 slower it is produced in the future. But after milking and massage carried out during her massage, the cow’s mammary glands are activated, and milk begins to be actively produced again.
If you decide to milk your pet three times a day, then the intervals between two milkings should be approximately 8 hours. That is, milking should begin at approximately 6:00 in the morning, at 12:00 in the afternoon and at 19:00 in the evening.
But with two meals a day, it is advisable to increase this period of time to 12 hours. Thus, if a cow was milked in the morning at 6:00, then in the evening this process should begin 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 it is difficult to maintain the indicated intervals, 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 - 9.
Many also combine milking time with feeding the cow. In fact, this is very convenient, since you don’t 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
There are two most common and problematic diseases in cows that affect the mammary glands and greatly affect the quality of the milk obtained. Therefore, if you decide to keep a cow, you need to be prepared for this.
How dangerous is leukemia 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 taking blood from an animal. But in addition to blood, the causative agents of leukemia can also be found in sperm, milk, and amniotic fluid (that is, the disease is transmitted from mother to calf).
It is very important to limit sick animals from contact with the entire 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.
And in the second, there are no clearly visible symptoms; the disease is determined by 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 doing this, it should be boiled well.
Unfortunately, but leukemia cannot be treated. The only necessary preventive measure is to check the blood of animals twice a year for the presence of infection.
Thus, if necessary, you can find out 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 cow’s severely inflamed mammary glands. Most often they pay attention to it during 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 of the cow's pen.
- During dry summer periods, when milk stagnates in the udder. Very often, during the dry period, mastitis appears due to the fact that it was not treated earlier.
- When an animal has a cold, when it has a high temperature for long periods of time.
- In case of improper milking.
Thus, the prevention of mastitis may well include adequate feeding, as well as compliance with all necessary sanitary standards for keeping cows.
If you have mastitis, you should never use milking using a special automated machine.
Mastitis can be determined by clots, pus, and sometimes even bloody traces that appear in the milk. 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 Mastidine to a few drops of milk. If the disease is present, the milk will become jelly-like and treatment of the cow must 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 must also be prescribed individually. To determine which antibiotic will be effective, it is necessary submit your cow's milk for analysis to a special veterinary laboratory.
Experts will definitely advise you on what can really cure the animal. You can treat a cow without a veterinarian, only after receiving detailed instructions from him.
Methods and secrets of increasing 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 prepared for the animal gives it a lot of energy, carbons, 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 carry out preliminary preparation before milking. Massages and careful attention to the cow also affect the amount of milk produced.
- It is very important that the cow is healthy. Also, in no case should you expose the animal to stress, since this can cause milk yield to drop significantly.
Milk quality: discussing positive and negative influencing factors?
The composition and properties of milk can change quite often, and this will not always indicate something bad.
For example, factors of such differences and changes may include:
- The breed of the cow, as well as its age. There are many dairy breeds that produce large amounts of fatty milk. With age, milk yield and quality indicators of milk decrease.
- The lactation period in which the animal is.
- Features of the cow's diet, as well as the conditions of its maintenance.
- Productivity level.
- Features and regularity of milking.
So, during the lactation period, that is, in 300 days, the milk of the same cow can change its properties three times. In particular, immediately after calving we receive not milk, but colostrum, which comes out of the udder for the first 5-7 days.
For the longest period we receive regular milk, which 10-15 days before calving is replaced by old milk, which has a 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, when chemically analyzing the composition of milk, the milk sugar content 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 fattier the milk will be. Proteins, that is, proteins, will also be included in the milk. Such feeding can also increase milk yield, raising it by 10%.
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9. Physiological basis of the process of machine milking of cows. Methods for extracting milk from a cow's udder.
The udder of a cow (Fig. 2.2) consists of four independent lobes, often unevenly developed. Most cows produce more milk in their hind lobes than in their front lobes. Each lobe has 1 mammary gland, 7 connective tissue, 2 milk ducts and a nipple. In the mammary gland, milk is produced from the animal’s blood, which flows through the milk ducts into the milk cistern 3 and into the nipple cistern 4.
The elementary structural unit of the mammary gland is the alveolus - a vesicle with a diameter of 0.1 to 0.4 microns, the walls of which consist of a single layer of secretory cells. The alveoli are located around the common excretory duct, forming a lobule that includes 150–200 alveoli (lobule length 1.5 mm, width 1 mm, height 0.5 mm). The lobules are combined into larger lobes with large ducts flowing into the cavity above the nipple - the udder cistern. The cow's udder nipple has a cistern 4, separated at the top by a round fold from the udder cistern 3, and at the bottom passing into a narrow teat canal, surrounded by a dense muscle ring - sphincter 5. Between milkings, the sphincter is tightly compressed, preventing milk from flowing out of the udder. Milk does not flow out of the udder between milkings also due to the special arrangement of the milk ducts, which have expansions and contractions, as well as special sphincter-like thickenings. Breast tissue is like a sponge and milk can only be extracted by squeezing it. Compression is carried out by contraction of the myoepithelium under the influence of the hormone oxytocin. By the beginning of the next milking, the udder tanks contain from 4 to 20% milk. The main part of milk - 80-96% - is located in the alveoli and small ducts of the mammary gland. It is relatively easy to extract milk from the cisternal section; it flows out on its own if you overcome the resistance of the nipple sphincter by inserting catheters into the nipples. To obtain milk from the alveolar region of the udder, it is necessary to induce the milk ejection reflex in the cow.
The entire process, the beginning of which is the irritation of the udder receptors, and the end of which is the transfer of milk from the alveolar region to the udder tank, is called the milk ejection reflex. This is a neurohormonal reflex, since irritation from the receptors of the mammary gland to the central nervous system goes along the nerve pathway, and from there the excitation is transmitted to the mammary gland both through nerves and through hormones.
The operator, by washing and massaging the udder, irritates the nerve endings (receptors) 6, from which excitation, passing through the nerves, enters the brain through the spinal cord. From the central nervous system, signals return to the mammary gland in two ways. One path is purely nervous (the first phase), when excitation returns to the mammary gland from the spinal cord, causing vasodilation and increasing blood circulation, dilation of the milk ducts and cisterns, which facilitates the passage of milk into them from the alveolar region. As a result of the first phase of the milk ejection reflex and relaxation of the nipple sphincter, the calf can receive a cisternal portion of milk within 2-6 seconds after the start of sucking.
The second phase of the milk ejection reflex includes, in addition to the nervous one, a hormonal component. This phase begins 30–60 s after irritation of nipple receptors and lasts 4–6 minutes. In response to irritation of the receptors of the mammary gland and the receipt of signals in the brain, the hormone oxytocin is released into the blood from the posterior lobe of the pituitary gland, which reaches the mammary gland with the blood and causes contraction of the stellate cells of the alveoli, while increasing the permeability of the walls of the secretory cells. Under the influence of oxytocin, the ducts shorten and expand, facilitating the passage of milk into the tanks, from where it can be easily removed by the milking machine.
As a result of repeated milking in constant conditions on the farm and the coincidence in time of the act of milking with certain environmental factors (time, place, sequence of operations on the udder, etc.), conditioned milk release reflexes are formed in cows and a stable stereotype of behavior during machine milking is developed.
Milk ejection that occurs as a result of direct irritation of the receptor zones of the nipples and udder is called unconditional reflex. Milk ejection that occurs as a result of the action of external stimuli on the nervous system through other analyzers of the animal (visual, auditory, olfactory, etc.) is called conditioned reflex. The milk ejection reflex (conditioned and unconditioned) occurs simultaneously in all lobes of the udder, despite the different amounts of milk formed in them.
The technology of machine milking of cows involves the following operations:
Creating a vacuum in the air system of the milking machine (installation);
Preparing the cow's udder for milking;
Putting teat cups on teats;
Milking and transporting milk to a storage tank;
Removing glasses from nipples.
All the most labor-intensive operations of machine milking are performed mechanized. The exception is preparing the cow's udder for milking, putting on and removing teat cups, which take 15...20% of the total milking time. Recently, robotic milking machines have been developed (mainly abroad - Holland, USA), in which the search for the cow's teats, putting on glasses, and removing them after milking is completed automatically. Udder washing and massage are also automated.
The main factors in organizing cow milking are the frequency and intervals between milkings. The frequency of milking is established taking into account the capacity of the udder and other biological characteristics of the cows, as well as the specific economic conditions of keeping the animals.
The intensity of milk production depends on the filling of the udder with milk. When it is less than half full, it is not recommended to milk cows.
Milk can be extracted from the udder naturally (calf suckling) by hand and machine milking.
Machine milking can be done in two ways: sucking milk using a vacuum and squeezing milk from the teats. The latter method, which imitates manual milking, has not become widespread due to the complexity of the design of milking machines.
To implement the technology of machine milking, technological lines are created, which represent a system of interconnected machines and units that perform all the necessary milking operations.
Zootechnical requirements for machine milking technology are determined by the physiology of the animal, and boil down to the following.
1. Preparatory operations on the udder must be completed within one minute.
2. Milking cups should be put on after the cow has let in her milk.
3. Milking of the most highly productive cows should be completed in 4...6 minutes. (milking speed up to 2l/min.).
4. There must be a complete drainage of milk from the nipple chambers of the teat cups during the period of greatest milk production.
5. It is necessary to ensure that the cow is completely milked by the machine without manual milking.
6. For push-pull machines, the teat cups must not be left on the teats after milk has stopped flowing from the udder.
In accordance with the requirements for technology, there are also requirements for milking machines. They should easily and quickly ensure the opening of the nipple sphincter, not subject the nipples to excessive compression, and not cause irritation; create a vacuum and the duration of the sucking stroke in accordance with intrauder pressure and the rate of milk flow. Milking cups should fit teats of various sizes, not creep onto the udder and not pinch the upper mouth of the teat canal. They must be held on the udder without the use of a special device.
The milking machine should be easy to manufacture and maintain, reliable in operation, should not require manual adjustment during the milking process, and should provide the ability to conveniently visually monitor the flow of milk from the udder.
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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 structure of the ducts and the presence of sphincters (compressor muscles) in the nipples. Milking is carried out thanks 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 careful milking, a certain amount (10-15%) of milk (residual milk) with a fat content of 9-12% remains in the udder.
Over time, lactating cows develop conditioned reflexes of milk release to the environment. The noise of the engine of the milking machine, the appearance of the milkmaid, and other conditioned stimuli cause compression of the alveoli and the release of a hormone from the pituitary gland, as in the normal process of milking, unusual stimuli (sharp noise, change in the usual environment, etc.) can inhibit the milk ejection reflex. Therefore, when milking, it is important to maintain silence and 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. Typically cows are milked 2-3 times a day, highly productive and fresh cows 3-4 times. Before starting, the number of milkings is gradually reduced.
Cows are milked two or three times during the day. In some cases, when milking three times, 10% more milk is obtained than when milking twice. 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. When the number of milkings is reduced from three to two, labor costs are reduced by 25-30%.
Compliance with the rules of milking technique helps to obtain maximum milk yield. The milking process consists of the main process and auxiliary operations. The operator does not directly participate in the main process of milking milk from the udder of cows using the machine. Auxiliary operations are divided into preparatory and final, which are performed by the operator on non-automated installations.
There are six preparatory operations: the operator moves 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 goes to the cow, machine milking, disconnecting and removing teat cups from the teats, monitoring the condition of the udder, draining the milk.
Udder massage has a particularly beneficial effect on the completeness of milking and the fat content in milk, which increases milk yield by 8-12% and the fat content in milk by up to 1%. So, the first portions of milk contain 0.5-0.7% fat, and the last -8-12%.
The health of a cow largely determines its productivity. For example, with tuberculosis, the milk yield of cows decreases by 20-35% compared to healthy animals, and with brucellosis - by 40-60%. Mastitis, diseases of the limbs, diseases of reproduction, and metabolism reduce milk yield by up to 20-50%.
Machine milking
When machine milking, the most favorable physiological conditions are created for the removal of milk from the udder: the machine simultaneously milks all four lobes of the udder.
On farms with tether housing, cows are milked in 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 free-stall housing and free-stall housing on deep litter, cows are milked in machine-type installations with a lower milk line. To milk cows in these installations, farms are equipped with special milking parlors (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 number of 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 the construction of a new milking platform is necessary. Its size is determined depending on the number of dairy cows and the duration of milking.
To achieve continuity of the milking process and more complete milking, modern units offer mechanical udder massage with electronic control.
The nerve receptors of 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 glasses and when the teat rubber pulsates during milking. To achieve optimal stimulation, a specific combination of pre-operations must last for at least 60 seconds. Since all these operations are manual, it is necessary to reduce their 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 teat rubber and the function of the stimulus is transferred to the machine. This occurs when using the ACE Pulse method (APF - alternative increase in pulsation frequency). Thanks to the interval increase in the pulsation frequency of the teat rubber to 200 double strokes per minute throughout the entire milking process, intense stimulation of the receptors is achieved.
This method allows, with the lowest technical costs, to distribute tactile stimulation throughout the entire milking period and make manual stimulation absolutely unnecessary at the beginning of milking. When using the APF method, a significant increase in milk yield in cows is achieved, compared to 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 housing. The design basis takes into account the needs of both the cow and the milker.
Milking is controlled by the flow of milk coming from the cow. All cows are different. They require an individual approach. Milk Master starts working on the phase low level vacuum with reverse pulsation. This gently stimulates the cow to begin milk production. As soon as the milk flow begins, the machine switches to the main milking phase mode with a normal level of vacuum and pulsation, so that the milking process takes place as quickly and efficiently as possible. The Milk Master display shows indicators of milk yield, milk flow speed or milking time. Four indicator lights show the individual milking phase. The red light on the top cover of the machine begins to flash slowly as soon as the cow has finished milking. Information about milk production and flow levels makes herd management more progressive. An unexpected drop in milk yield can be the first signal of the start of heat or a symptom of a disease. Information read from the milk yield indicator is a powerful tool for monitoring the effectiveness of feeding changes at the beginning of lactation.
The automatic release device for the milking machine facilitates the milking process. This device is controlled by Milk Master. The red light starts flashing as soon as the milking unit is detached from the udder.
Selection and formation of groups of cows for milking on sites
Cows that meet the following requirements are suitable for milking cows on milking platforms:
They have a bathtub-shaped, cup-shaped and rounded udder shape, the bottom of the udder is flat, its distance to the floor should be no less than 45 and no more than 65 cm;
The length of the nipples 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 nipples is from 6 to 20 cm, between the rear ones, and between the front and rear ones from 6 to 14 cm;
The udder quarters must be evenly developed - the permissible difference in the duration of milking of individual quarters is no more than 1 minute;
The duration of milking a cow is no more than 7 minutes;
The permissible volume of milk after milking should be no more than 200 mg, with no more than 100 ml from a separate quarter.
The “Tandem” installation can be recommended primarily for those farms where there is no herd selected in terms of milking time and milk production rate. At the same time, to achieve maximum productivity in the Herringbone installation, cows must be selected for milk production rate and productivity.
When transferring animals to milking in milking parlors from linear milking machines, it is necessary to accustom them. Cows are accustomed to the sounds of the milking parlor, the weight of the udder and other technological procedures.
Cows are selected into groups according to their physiological state: fresh (1-3 months after calving), first half of lactation (3-6 months), second half of lactation (6 or more months). Groups of queens are formed according to the duration of milking time and the rate of milk production. The order of movement of cows for milking should be organized taking into account their physiological state: first, fresh cows, 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 production, which is regulated by the nervous and humoral system of the animal, its conditioned and unconditioned reflexes.
The process of machine milking of cows includes preparing the milking machine and the udder of cows for milking, the milking process itself (putting on milking cups, monitoring the milking process, machine milking and removing milking cups).
On milking machines of the “Tandem” or “Herringbone” type, the udders are washed out of the hoses using a special sprayer. Along with washing, the udder is lightly massaged, which promotes a more active milk supply. Thanks to these actions, the cows become ready to produce milk, which is noticeable by the swelling of the udder nipples, which become more elastic and pink. If the milk release reflex does not occur after washing and wiping the udder, then the operator quickly performs a massage, clasping individual quarters of the udder with his fingers and stroking them down towards the nipples. In some cows, the milk letdown reflex is triggered only by nipple massage. Before putting on the teat cups, one or two streams of milk are milked from each nipple. When milking the first streams, the operator determines the presence of an allowance of milk, the condition of the mammary gland, and frees the outlet channels from bacteria contained in large quantities in the first streams.
The first streams of milk are milked into a special mug with a removable plate or a dark strainer. This makes it possible to detect a cow’s disease with mastitis (the presence of flakes, blood, mucus and other changes in the 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 should not milk the first streams onto the floor, as the milk of sick cows can be a source of infection.
When milking on “Tandem” or “Herringbone” type units, the first streams of milk are milked before the udder is washed and massaged. A cow that has swelling, redness, induration and sores on the udder and teat cannot be milked with a machine. It must be milked by hand into a separate bowl. After this, hands should be thoroughly washed and disinfected.
Wash and boil the towel used to wipe the udder. 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 milking cups. To do this, by opening the milk tap or lowering the clamp on the milk hose, he brings the apparatus under the udder with one hand, and with the other, one by one, puts the glass on the nipples. To avoid leaks, you need to lift the glass up and at the same time bend the milk tube so that air does not get sucked into the glass. Long-term air leaks reduce the vacuum in the main pipeline, which worsens the operating mode of other already operating devices. When the glasses are put on correctly, you won’t hear any hissing; they need to 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 his right hand, with the thumb and index fingers remaining free. With their help, the nipple is directed into the milking cup. After putting on the glasses, the operator must make sure that the machine is working properly and milk is being milked intensively, only then should he approach the preparation of the next cow.
Maintaining the sanitary condition of the milking machine and dairy equipment
Milking equipment is sanitized after each milking by performing the following operations:
Wash the outside of the milking machines with warm water from a sprayer, insert glasses into the milk heads and prepare all equipment for washing;
Rinse in circulation with a 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 residual detergent and disinfectant solutions.
Circulation washing with detergent and disinfectant solutions is carried out within 10-15 minutes.
In addition to washing and disinfection, milking equipment should be periodically disassembled, washed and cleaned manually.
When performing circulation washing, it is necessary to disassemble the corner pipes, the milk collector, the milk counter - once a week, and the milking machines - once a month.
To prevent the formation of milkstone, 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 the water for washing milking equipment, since the use of increased 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 the quality of milk.
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) wash off the remaining cleaning solution with warm water;
d) disinfected with a disinfectant solution;
e) washed with tap water until the disinfectant is completely removed.
When using dezmol as a detergent, additional disinfection is not required.
At least once every two weeks, you should completely disassemble the milking machines, thoroughly wash and disinfect all its parts, paying special attention to the teat rubber. Rubber parts are checked for their further suitability, then kept for 30 minutes in a 1% washing solution at a temperature of 70-80 ° C, after which they are washed with brushes and brushes and rinsed with hot water.
The remaining parts, immersed in a bath with a hot 0.5% washing solution, are washed using brushes and brushes, then immersed in clean water at a temperature of 70-80°C for 20 minutes. After washing the parts, assemble the devices and pass 10 liters of hot disinfectant 0.1% solution through them.
Once every 6 months, all rubber parts in the devices are replaced with new ones, and the removed parts, after thorough disinfection and degreasing, are placed to “rest” in special devices.
When testing milking equipment, it is necessary to pay attention to all components of the milk line, the internal surfaces of which come into contact with milk: milk taps, pumps, intake hoses, which must be regularly disassembled and washed with detergent and disinfectant solutions using brushes.
Exposure to alkaline detergents may result in the formation of a white coating on the inner walls of the milk pipe. To remove it, the milk line is washed with a 0.2% solution of acetic or 0.15% solution of hydrochloric acid.
