Effective production and collection of high-quality milk is the goal of most farmers working in dairy farms. Milk of high quality should be beautiful in appearance, should not contain impurities and should meet special standards for the quality of milk for the content of somatic cells (SSC), as well as the indicator of bacterial contamination.
Молоко наивысшего качества обычно имеет ССК ниже 200,000 ед/мл. Многие хозяйства штата Висконсин производят молоко высокого качества. В 1998, приблизительно 40% производителей молока первой степени имели годовой показатель ССК <250,000 (Рис.1).
Рис 1: Средний показатель ССК среди молочного поголовья первой степени штата Висконсин Январь-Ноябрь 1998*
Producers of high quality milk know that the constant method of hygienic preparation of the udder to milking and invariably the same attachment of milking machines in good working order is very important.
The purpose of monitoring the milking process is to make sure that the disinfectant solution is applied to visually clean, carefully stimulated nipples, and that the milk collection takes place quickly and efficiently, and that the milking machines are disconnected after the milking is completed.
Dairy farms use a variety of different milking schemes. According to a study conducted among 278 milk producers in Wisconsin, 28 different schemes for preparing cows for milking were recorded.
The concept of a "universal" milking method is not suitable for milking animals, but nevertheless, there are 7 principles of a highly effective procedure for preparing cows for milking, which contributes to the production of high-quality milk.
1. Cows are calm and clean before milking
The purity of cows is the main determinant of both milking efficiency and the degree of infectious diseases of the breast. It is estimated that cows coming to the milking parlor are dirty, increase the time for preparing the udder to milk twice and, thereby, reduce the milking parlor performance.
Based on the results of a study in France, it was found that udder cleanness is a fairly reliable factor capable of predicting the average number of somatic cells in milk. Disease-causing microbes that live in the environment are often the main source of mastitis in farms where the problem of contagious mastitis has been eliminated.
Bacteria that live in the environment (such as E. coli and streptococci) can often be found in litter from organic material, as well as in damp, dirty sections.
In farms where the exposure of nipples to the negative effects of pests is minimized, the risk of developing mastitis is also significantly reduced. A dry, clean and comfortable litter, such as sand, will minimize the growth of pathogens.
Litter consisting of inorganic material, such as sand, is often the best choice to reduce the number of pathogens. It is important to note that the sand may be of different qualities and that the litter of this material must be treated daily by rakes. If the stalls are equipped with rubber mats, it is very important to organize the work with the litter correctly, so that it always remains dry.
The next step in improving the cleanliness of the cow can be removing the udder's hair. Regular hair removal from the udder is a good practice. This procedure can be carried out once a month or more often, if necessary.
The ability to handle a cow is also an important determinant of fast and efficient milking. Emission of adrenaline in animals, even 30 minutes prior to the beginning of milking, can prevent the normal return of milk and, thereby, significantly prolong the time of milking. Calm cows enter the milking parlor much more easily and usually do not defecate during milking.
Employees of the dairy complex, working directly with animals, including livestock drivers, during work should observe peace and quiet. If a large number of cows resisting go into the milking parlor or often defecate on milking, it is necessary to pay close attention to the work of the operators of machine milking, as well as the organization of work in the milking parlor.
2. Cows are grouped
There are at least two reasons, not caused by the diet, for grouping cows. Separation of cows with identified mastitis into a separate group is a prerequisite for preventing the occurrence of new infections.
In farms with a non-tethered type of keeping animals, uninfected cows should be grouped together and milked first. Cows, with an indeterminate infectious diagnosis, are followed. And only in the last place are the cows with confirmed infection.
Sometimes it is necessary to manually disinfect the devices between milking cows. To achieve the desired reduction in the number of pathogens, the milking equipment should be rinsed with water with iodine for at least 30 seconds, after which the apparatus must be rinsed with clean water and dried. For effective milking of cows in the milking parlor, grouping cows is an important element.
3. The constant system of preparing the cow for milking
Cows love the routine milking process and certainly reward operators who perform it. According to studies, when the routine milking program is implemented, milk yield is observed to increase by 5.5% compared to the random milking process.
Achieving consistency in milking can be a difficult task if the farm employs a large number of operators. With a large number of different operators to achieve high-quality milk production, it is necessary to develop a clear routine milking scheme and train people to perform it.
Preparing the cow for milking is a balance between speed (efficiency), performing the required steps to clean the udder and stimulating the nipples for milk yield.
Initially, milk accumulates in the secretory tissue of the udder (alveoli), after which the effective yield of milk is accelerated by coordinating the connection of devices with milk yield. Milk yield is a combination of production of oxytocin (from the pituitary gland) and stimulation of the local nervous system providing feedback to the muscles surrounding the alveoli for the release of milk into the teat canal for further collection.
The choice between high milk yield and the need to increase the number of cows in the milking parlor led to controversies about the need for manual stimulation of the animal before connecting the apparatus. Based on the results of six studies comparing two approaches to milking, the first approach was to refuse stimulation of the udder (just a connection), and the second approach advocated stimulation (at least 20 seconds manual stimulation and connection after 60 seconds) came to the conclusion, That manual stimulation indisputably has a number of advantages (Table 4).
Table 4: Conclusions from six studies on the effectiveness of cow stimulation before milking
|Index||Lack of stimulation||Optimal stimulation|
|Milk yield per milking, kg||10,4||10,8|
|Milk flow rate per minute, kg||1,8||2,1|
|Machine time in action, minutes||6,3||5,5|
Solving the first milk jets is a method of stimulating the cow to milk yield, eliminating microorganisms in the milk of cistern and identifying clinical mastitis. Pre-suction is effective in surrendering 2-3 milk jets.
The problems of the increased somatic cell count in the milk tank cannot be solved without including the procedure of surrendering the first jets to the routine milking scheme. The most dangerous bacteria live on the ends of the nipples. It is important to disinfect the nipples to reduce the number of bacteria. It is proved that good disinfection can reduce the number of bacteria by 75%. Reducing the number of bacteria on the nipples reduces the level of mastitis.
There are many questions as to which method is best for the disinfection of nipples. Dairy farms in Wisconsin vary considerably in the ways of nipple disinfection, depending on the type of animal maintenance.
Pre-milking is the most effective way to control pathogens living in the environment (such as E. coli and streptococci), but not very effective in fighting coagulase-negative staphylococcus. For effective disinfection, at least 20-30 seconds of exposure to the nipple should be done.
4. Dry nipples
The most important part in the disinfection of nipples is drainage. Drying the nipples with air is not a satisfactory alternative to draining, carried out manually with the help of individual tissue towels or paper napkins. Wet nipples allow skin bacteria to easily penetrate the breast and reduce friction between the nipple and the teatcup.
Fabric towels absorb moisture much better than paper napkins. When using fabric towels, they should be disinfected by washing with bleach or in hot water. After washing, the towels should be dried at a high temperature in automatic drying.
These methods showed a significant decrease in the number of pathogens. In addition, milking in latex or nitrile gloves can also reduce the transfer of pathogens. Gloves protect the skin of milkers and reduce the risk of nipple contamination through the hands of operators. Gloves can be easily changed between milking groups of animals, thereby contributing to reducing the risk of harmful microbial transport.
In order to test the effectiveness of disinfection and dehumidification of the nipples, using a clean alcohol cushion. Wipe the end of the teat with a pad before attaching the milking machine. If the nipple has been carefully processed, the pouch will remain clean. A dirty little pillow means that the method does. The nipple treatment needs to be changed.
5. The devices are correctly connected
An important element in connecting devices is the time delay. The time from the beginning of the preparation of the animal to milking and before the connection of the apparatus to the udder is considered to be the time of "preparatory delay".
To maximize milking efficiency, the milking machines should be connected one minute after the start of the stimulation. The time interval is 45 sec-1 min. Is acceptable. "Preparatory delay"> 2 min. Led to the formation of residual milk and reduced productivity.
If the recommended time of "preparatory delay" is maintained, a large flow of milk can be observed after a few seconds after connecting the device. Before you start working with the program of preparing animals for milking, you need to decide how many animals will be processed by each operator before connecting.
There are several developed schemes according to which the operator serves groups of animals consisting of 3, 4 or 5 cows to make sure that the time of the preparatory delay is maintained, as well as the time of interaction of the solution with the nipple.
After that, the usual process of connecting devices follows. During the connection of individual glasses for the nipples, each glass should be directed toward the nipple, while it is necessary to align the teatcup and minimize air access.
It is necessary to correct and regulate the apparatus so that the weight distribution of the apparatus is uniform. Milking devices should be installed in such a way that the outlet of the milk hoses is directed directly towards the head of the animal (in the milking parlor of the "Yelochka" type) or directly between the legs (in parallel milking parlors).
Correct adjustment of the apparatus reduces the slipping of the teatcup.
6. The apparatus is properly disassembled
Milking is considered complete when the available milk is fully harvested. Incomplete milking occurs when the milk is not completely extracted ("the cow is not extorted"). Excess milking happens if the device is attached to the nipples, and milk does not enter it.
The greatest danger of unfinished milking is financial, excessive milking - damage to the ends of the nipple, which leads to the disease of mastitis.
In the course of the experiment in Denmark, it was shown that with an increase in the limit of automatic switch-off settings from 200 g / min to 400 g / min, the average performance of the device is reduced by 30 seconds and the nipple health improves.
Additional time savings can be achieved by changing the delay time of the device's disconnection after the limit of the automatic shutdown setting is reduced from 20-30 seconds to 10 seconds. In order to avoid the loss of milk nodos, the changes in the delay time of the device detachment should be made gradually with an interval of 3 seconds.
Setting a high limit and a short delay time interval can be practiced for a herd with three meals a day and a good preparation of the cows for milking, which leads to an improvement in the state of the nipples of animals and an increase in the speed of milking.
Completeness of shedding can be assessed by periodic checks by manually donating milk jets after the milking is completed. The remainder of the milk that is released when handing is handled is called residual milk yield.
Корова может считаться полностью «выдоенной», если после завершения дойки можно вручную сдоить <0.20 литра молока с четверти. Ручное сдаивание не должно стать регулярной практикой.
7. Hygienic treatment of cows after milking
Initially, the practice of disinfection of nipples after milking was developed in order to reduce the transfer of pathogens that cause contagious mastitis, after which it was widely accepted. To assess the effectiveness of using a nipple spray, wrap the nipple with a paper towel after applying the solution. The carefully crafted nipple will leave traces on all sides of the towel.
Finally, the last step on the way to an effective milking procedure is to make sure that the cows do not go to the stalls for 30 minutes after the milking is completed. To achieve this goal, most manufacturers distribute fresh feed so that the animals come to the feed table after milking.