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In dairy buffalo production world-wide, milking is one activity that is considered to be sensitive and labour intensive. In general buffalo are known to be difficult to milk. A number of researchers from different parts of the world have reported the problem of disturbed milk ejection and rapid termination of lactation when calves die or if the usual milker is replaced (Sastry and Tripathi, 1988). In a survey in India on prevailing milking practices, it was reported that most farmers have experienced these problems with their buffalo. In order to overcome the problems, 65% of the farms surveyed used concentrate feeding during pre-stimulation to improve milk let down, while 13% used injectable oxytocin to induce milk ejection (Varma and Sastry, 1994). Although not documented it is a well known practise in large buffalo herds, to use oxytocin injections to achieve milk let down. One of the disadvantages of this is that continuous oxytocin treatment could lead to addiction (Bruckmaier, 2003). To avoid these treatments and their side-effects, it is necessary to understand the factors that influence the efficient extraction of buffalo milk, such as milk accumulation, storage of milk, and milk ejection.
Much work has been done on the milking management of dairy cattle, sheep and goat, but comparatively little research data is available on the milking management of buffalo (Sastry and Tripathi, 1988). DeLaval has been conducting research at different levels in different parts of the world to develop machine milking techniques that suit the species-specific requirements of buffalo. DeLaval was the first to supply milking machines to buffalo farmers in Italy. In the past decade DeLaval has been the major supplier of milking machines to buffalo farmers in India, Egypt and Europe.
In most developed dairy countries where there is milk production, machine milking has been successfully practised for more than 30 to 40 years. In India today more and more buffalo farms all over the country have started using machines to milk their buffalo herds. There are many farms where herds of 300 to 500 buffalo are now machine milked (Thomas et al., 2004). Soon there will be a major shift towards machine milking in large and small buffalo farms all over India, because of the advantages and convenience of machine milking buffalo. This change will be driven by several important factors. It is more economical to machine milk buffalo in commercial dairy herds. Apart from the economic benefit, other benefits include ease of operation (ergonomics) as the milker does not have to sit crouched under buffalo, improved milking hygiene, and improved milk quality.
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| Machine milking of buffalo in a parlour on a large commercial farm. |
Machine milking with a bucket milking machine on a small family farm. |
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Anatomical and physiological differences between cattle and buffalo with respect to milking
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Several factors have a bearing on the complete removal of milk and stripping yields during machine milking. These factors include teat length, teat thickness, teat canal length, effective diameter of the teat canal during milking, the minimum and maximum biological force that keeps the teat canal closed, and the stiffness of the teat when full of milk prior to milking. |
Bowl shaped udders in Murrah buffalo. |
In buffalo the variation in udder shapes is much greater than in dairy cows, because most buffalo are not selectively bred. Buffalo udder shapes can be classified as rounded, bowl shaped and cup shaped. Bowl shaped udders are found on 65% of Indian Murrah buffalo. This udder shape is more desirable than others as these udders extend forwards and backwards rather than downwards (Sastry and Tripathi, 1988).
Buffalo have much longer teats than dairy cattle. The front teats are, on average, 5.8 to 6.4 cm long, with a diameter of approximately 2.5 to 2.6 cm. The hind teats tend to be 6.9 to 7.8 cm long and their diameter 2.6 to 2.8 cm (Thomas et al., 2004). Among Indian Murrah buffalo the different teat shapes can be classified as bottle shaped, conical and cylindrical: 60 to 80% have cylindrical teats, 15 to 30% have conical teats and just 3 to 8% have bottle shaped teats.
The epithelium of the streak canal is thicker and more compact in buffalo than in cattle. The sphincter muscle around the streak canal is thicker in buffalo than in cattle. More force is therefore required to open the streak canal. The teat sphincter tonus has been reported to be at least 400 mm Hg negative pressure in buffalo (the tension falls slightly after calf suckling and hand milking). The length of the streak canal in buffalo ranges from 1.9 to 5.5 cm compared to 0.5 to 1.5 cm in cattle (Thomas et al., 2004). These are some of the major causes of buffalo being categorised as “hard milkers”.
Cylindrical shaped teats are the most desirable but they should not be more than 5 cm long with a diameter of not more than 2.5 cm.
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In most mammalian species the mammary gland consists of secretory and ductal tissue. Among the prominent dairy species of cattle, goats and sheep, as milk secretes it is transferred within the gland via the ducts into a large cistern that drains out from a single orifice for each lobule (cluster of alveoli). As a consequence, a relatively large portion of the secreted milk is stored as the cisternal fraction of milk in these species. The cisternal area of the mammary gland in dairy species is referred to as two separate cavities, the teat and gland cisterns. Of the total milk secreted in 10 to 12 hours in cows, the cisternal fraction has been reported to be between 20 to 40% while in goats and sheep, the cisternal cavities are relatively larger than in cows. However recent studies on buffalo where the cisternal and alveolar fractions were measured separately revealed that in buffalo 95% of the milk secreted between milking is stored in the secretory tissue (Thomas et al., 2004).
The rate of milk secretion and the process of milk removal are both influenced by the size of the cistern. In both sheep and cattle, it is evident that animals with large cisterns are better producers of milk and are well adapted to milking routines with longer milking intervals and short stimulation. It is also reported that animals with small cisterns are more susceptible to the short-term autocrine inhibition of milk secretion where the presence of milk in large quantities in the secretory tissue leads to reduced milk secretion. This effect is less intense if the milk is accumulated in the cisternal area and not in close proximity to the secretory tissue. In buffalo the cisternal area is relatively much smaller than in cattle, sheep and goats, so it is possible that if large portions of milk remain in the secretory tissue, not extracted, it could lead to an immediate drop in milk yield. It is therefore crucial to empty the udder of buffalo efficiently during milking.
Milk ejection in mammals is a process that is controlled by the maternal instincts of the lactating animal. It is a complex process involving a number of interactions between the mother and her young. The lactating animal’s eyes and ears recognise a calf as it approaches for suckling, and she identifies her own calf by smelling it. When the infant or young one suckles the teat, this triggers milk ejection. The teats are densely supplied with nerves and have a large numbers of receptors that are sensitive to touch, pressure and temperature. The stimulus received by the teats is conducted via the spinal cord to the pituitary gland causing the release of oxytocin, the milk ejection hormone. As a consequence of increased blood levels of oxytocin, myoepithelial cells surrounding the secretory tissue in the udder contract and milk is expelled out into the cisternal area. However milk ejection can be easily disturbed by stress, pain or any other perceived threat situation that is part of the fight or flight mechanism in mammals.
In dairy cows hereditary traits like milk ejection have been improved by selective breeding and the large volume of milk produced by these animals further influences quick milk ejection. Thus modern dairy cows are conditioned to respond to stimuli like feeding during milking, the presence and touch of the milker, and the sound of the milking machine.
Buffalo have not been selectively bred to the extent that dairy cattle have been, hence the maternal instinct remains dominant in them and they can be easily disturbed by even small changes in milking routines. Since buffalo have very little milk in their cisterns prior to milk ejection, if they are disturbed and milk ejection is inhibited it results in more than 95% of the secreted milk remaining in the secretory tissue. Thus it is possible that if buffalo are repeatedly disturbed during milking, milk secretion could be inhibited and milk yield affected.
In a short-term experiment different pre-stimulation treatments were studied to evaluate their influence on milk ejection. (Figure 10:1-3. Thomas et al., 2005). The treatments evaluated were: manual pre-stimulation and feeding during milking, manual pre-stimulation without feeding, and direct machine milking without manual pre-stimulation. Buffalo responded best to manual pre-stimulation and feeding during milking. Their normal milking routine, with manual pre-stimulation and in-parlour feeding, resulted in good milk ejection and oxytocin release.
From this study it is evident that buffalo are easily disturbed by even small changes in the milking routines. It is therefore crucial to introduce machine milking gradually, along with good milking procedures, to buffalo who have not previously been machine milked. DeLaval has researched techniques for conditioning buffalo to machine milking and we have observed that it takes about five to seven days to completely accustom buffalo to machine milking and to obtain normal milk yields (Lind et al., 1997).
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The presence or absence of cisternal milk in the different dairy species is important when machine milking. In sheep and goats the large cisternal fraction of milk is available for a comparatively longer time at the start of machine milking, so a lack of pre-stimulation does not have a critical influence on milk removal. In dairy cows machine milking without pre-stimulation can cause a temporary reduction in milk flow (bimodal milk flow) or a total interruption in milk flow after the cisternal fraction is extracted. The consequence of this can be milking on empty teats until the alveolar milk is available. In sheep, goats and cattle emptying of the large cisternal fraction during machine milking can stimulate the flow sensitive receptors situated in the teat canal and cistern, possibly resulting in a complete and better ejection.
Buffalo have longer teats and long teat canals than dairy cows, and it is important to take this into consideration in machine milking (Thomas et al., 2004). This is one of the reasons why a different vacuum level has to be used when machine milking buffalo. In the absence of cisternal fraction of milk the teats of buffalo are empty, and thus during machine milking they may be similar to the teats of dairy cattle towards the end of milking. In the absence of the cisternal fraction, if the milking unit is applied prior to milk ejection, the empty teats are exposed to vacuum. Vacuum suction causes the teat canal and milk ducts to collapse, preventing further milk flow. This may be painful for the animal and could lead to inhibition of milk ejection.
However, milking with the DeLaval milking system for buffalo that has Duovac™ as part of the milking unit, minimises the impact of milking on empty teats. Duovac is a milk flow controlled milking system which synchronises with each individual animal’s milk ejection and milk flow pattern (Figure 11).
The milking process using Duovac™. (DeLaval, 2001,
Efficient Milking)
When the Duovac milking unit is applied, machine milking commences on low vacuum. When milk flow from the udder increases to above a certain set level, e.g. 200 ml/min., the vacuum automatically increases to the normal milking vacuum and stays that way until the milk flow falls below that set level, i.e. 200 ml/min., towards the end of each milking (Figure 12). In this way the Duovac system gently stimulates let down, and is gentle on the teats after the peak flow.
1) Low flow with low vacuum
2) High flow with milking vacuum
3) Low flow with low vacuum
This milking system is ideally suited to the physiology of buffalo milk ejection and milk flow. Since prior to milk ejection buffalo teats are usually empty, milking them using Duovac is not stressful for the animals. In addition by using an electronic pulsator the pulsation ratio can be modified: in the initial low vacuum phase during Duovac milking the massage time can be increased so that the teats are massaged longer while there is no milk in the teats. This is beneficial to the animal as it causes minimum accumulation of tissue fluids at the teat tip.
In another short research project designed to optimise milking routines in buffalo with respect to milk ejection, milk flow and milking efficiency, 24 buffalo in four groups were studied (Thomas et al., 2005). Milk yield, stripping yield, milking time and milk flow during machine milking were recorded. There were five treatments (randomised design): direct machine milking (no pre-stimulation), one minute manual pre-stimulation, three minutes manual prestimulation, reduced vacuum during early milking (Duovac), and intravenous oxytocin injection. Figure 13:1-5, tactile stimulation and milk flow, shows some of the observations from this study.
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1) Milk flow in buffalo begins only after an active milk ejection. |
2) Cisternal milk fraction is not visible in milk flow curves so pre-stimulation is needed. |
3) Inadequate stimulation results in disturbed milk ejection. |
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4) Tactile pre-stimulation in machine milking is more efficient at low vacuum (Duovac). |
5) Low vacuum milking (Duovac) avoids cluster climb and obstruction of milk flow. |
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Machine stripping with Alfadast
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Long teat canals in buffalo necessitate stripping. The DeLaval Alfadast system provides an excellent solution for machine stripping buffalo, which is otherwise a tedious manual task.
An appropriate milking routine is important for hygienic and production reasons as well as to create a comfortable and stress free environment for animals and milkers. It is easier to maintain good hygiene and to facilitate buffalo acceptance of relief milkers if a consistent milking routine is followed. With dairy cows it has been demonstrated that the practicing of a regular strict milking routine results in increased milk production.
The routine outlined here can be followed by both hand and machine milkers in stanchion barns or where milking is carried out in flat barns. In the case of hand milking in such barns, points six to nine are omitted. Routine checks of the milking machine should be done before each milking session according to the manufacturer’s recommendations.
1. Start by tying (if not already tied) and feeding the buffalo.
2. Remove dung from the floor.
3. Wash hands with soap and dry them.
4. Clean the teats with special towels
and massage teats thoroughly.
5. Foremilk the buffalo by hand into a strip cup, checking the appearance of the milk.
6. Apply the cluster gently. Check tube alignment.
7. Check the buffalo every now and then to make sure that she is comfortable with the machine.
8. Palpate the udder to check that it feels empty.
9. Remove the cluster gently.
10. Dip the teats in a suitable disinfectant solution.
11. Clean all the equipment in the milking room.
(Ståhl Högberg and Lind, 2003)
When machine milking, it is important that the milking machine is nearby and ready to be applied to the udder at the right time (after pre-milking). Thus, each buffalo must be cleaned, massaged and pre-milked and then have the machine applied directly. It must be emphasized that it is not possible to clean the udders on all the buffalo first and then apply the machines to the first buffalo. The oxytocin release has just a short duration (a few minutes).
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Milking buffalo in a tandem parlour means that the buffalo can be released one by one.
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Bucket milking in a small parlour. |
Pre-milking routines are as important when milking buffaloes as when milking cows. It is important to use a smooth and comfortable milking technique. The “knuckling” or “stripping” method is used in the wrong belief that it overcomes resistance in the teat sphincter. These milking methods might cause elongation and damage to the teats. A much more comfortable and appropriate method is the “full hand” technique. This technique imitates the calf’s suckling and is therefore a better stimuli (DeLaval Efficient Milking, 2001).
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Since the udder and teats in buffalo are different from those in cattle, milking machines for cattle have to be modified to suit buffalo. Results from recent studies in India indicate that it is possible to reduce the cluster weight and the frequency of liner slip by applying an appropriate combination of liner design and cluster weight. It is not only the total weight of the cluster that is important, but also the distribution of its weight on the udder. Unequal weight distributioncan cause uneven milk output. The long milk and vacuum tubes should be aligned and stretched to ensure equal weight distribution of the cluster on the udder.
Milking characteristics depend upon vacuum levels and pulsation rates among other factors. Studies on Egyptian buffalo revealed that a vacuum of 51 kPa and a pulsation rate of 55 cycles per minute led to much longer milking times than a vacuum of 60 kPa and a pulsation rate of 65 cycles/min. (6.21 min. compared to 3.18 min.). The higher vacuum level, however, caused a significant increase in somatic cell counts. The highest milk yield within an acceptable time was found when using 56 kPa and 65 cycles/min. In all trials a pulsation ratio of 50:50 was used.
Studies in Pakistan indicated that the pulsation rate and ratio should be 70 cycles/min. and 65:35 respectively for Nili-Ravi buffalo.
In Italy, the majority of farms use the same machines for both buffalo and cattle. It is a simple “cattle machine” with one vacuum level operating at approximately 40 cm Hg.
In India, recent trials have been made with milking with Duovac from DeLaval. Successful milking was done with a vacuum level of 55 kPa, 70 cycles/min. pulsation rate and pulsation ratio of 65:35 for milk flows above 0.2 kg/min. For milk flows under 0.2 kg/min. the respective data was 38 kPa, 48 cycles/min. and the same pulsation ratio.
In order to obtain all the advantages with machine milking the correct technique must be used. Both milkers and buffalo must be familiar with the machines. If the buffalo are scared or feel uncomfortable they will withhold their milk and thereby yield less. This in turn will lead to economic loss for the farmer and eventually he will lose his faith in machine milking.
The concept of machine milking should be introduced slowly by people with whom the buffalo are familiar and feel comfortable with, under the supervision of an expert. The procedure noted here for introducing buffalo to machine milking is recommended by DeLaval. It is applicable for a whole herd where neither animals nor people are familiar with machine milking. A successful introduction should be possible by carefully following these steps:
• Training personnel. Training of milkers should be done by a person from the milking machine company. This person will have good knowledge of the biology of milking, and of machine milking, as well as of the design, function and maintenance of the milking equipment. The training should include introduction procedures, the milking routine, handling the machine, cleaning and maintenance as well as certain aspects of the day-to-day servicing of the machine.
• Installation of the milking machine in the barn and any other modifications to the barn should be made well in advance of changing to machine milking.
• It is most appropriate to start with heifers since it is easier to habituate heifers than older buffalo to machine milking. Older buffalo may have been hand milked by a certain
routine for several lactations and may respond negatively to a change in routine. Heifers on the other hand are not accustomed to any specific routine and are more likely to accept machine milking just as well as hand milking. Furthermore their udders and teats are more uniform and not damaged by previous milking. Liner slip and other negative effects of machine milking are therefore less pronounced in heifers. Note that heifers should not be hand milked but directly introduced to the machine. They may get accustomed to the noise of the vacuum pump etc. by participating in the milking routines prior to partus.
• Calm animals that are comfortable with hand milking should be selected. The udders and teats of the animals should be uniform in conformation and size. Buffalo in heat or unhealthy animals or animals with previous let-down problems should not be selected.
• Milk the old and selected animals as usual by hand but let the vacuum pump run during milking. This will accustom the animals to the noise. Put the pump on before actual milking, but after the buffalo have been tied up, as the animals may be startled by the sudden noise. Repeat the procedure (usually two to four times) until all buffalo are accustomed to the noise. It is better to repeat this procedure once or twice more until all buffalo are comfortable, rather than rushing into the next step.
• Bring the milking machines into the barn. Connect them to the air line and place them at each buffalo’s place at the same time as hand milking is carried out. This will allow the
buffalo to get used to the ticking sound of the pulsator. It will give them a chance to look at the machines and smell them and maybe even to taste them. Make sure though, that they do not chew on them!
Move the machines to the next buffalo in order of being milked. This accustoms the buffalo to machines being moved around. The procedure should be repeated (usually two to four times) until all the animals have accepted the presence of the machines. At this stage all the
buffalo should be well accustomed to the new routine.
If some buffalo are still showing signs of nervousness or stress, it is recommended to repeat the above mentioned steps until the animals are calm. Buffalo that after this procedure have still not accepted being milked by machines, should be returned to hand milking. One or two frightened or uncomfortable buffalo might cause major disturbances in the whole herd.
Be consistent with the milking routine, including pre-milking preparation, right from the beginning of this introduction to machine milking. The regular milker should carry out machine milking during the introduction period. When the cluster is firmly attached to the udder, the milker should stay with the buffalo to see that she is comfortable. Soft talking and brushing and scratching are the best ways to calm an animal.
These first sessions of machine milking usually require more time than those following. However, this time is well worth spending to ensure calm and easy-milking buffalo for the future.
Mastitis, inflammation of the mammary gland, is a common disease in dairy animals. The disease causes great economic losses both for farmers and for dairies.
Mastitis may be caused by several factors. Most common is bacterial infection. Good hygiene practice is the most efficient way of preventing the disease from developing and spreading. Mastitis may also be caused by trauma such as injuries on the udder or the teat. Sores are a perfect way of entry for bacteria.
The most common bacteria causing mastitis in buffalo are Staphylococcus (Staph. epidermis and Staph. aureus), Streptococcus (Str. dysgalactia and agalactia) and Coryonebacterium spp. This is not very different from the incidence of respective bacteria in cattle mastitis. There is, however, a difference in bacteriology of the mastitis due to the kind of farm the buffalo come from. On modern farms the most common bacteria causing mastitis is often Staph. aureus. On traditional farms, Streptococcus faecalis, Escherichia coli and Clostridium perfringens are the most prevalent.
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Leucocytes |
Lymphhocytes |
Monocytes |
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Macrophage |
Epithelial cells |
Cell fragments |
Prevailing recommendations for hygiene, milking routines and herd management should be followed regardless of whether milking is carried out by hand or machine. Machine maintenance is important, with two basic requirements being regular servicing of milking machines so they continue to operate with appropriate vacuum levels; and regular liner replacement.
Mastitis risk on traditional buffalo farms is often linked to lack of even the most simple hygiene routines. The bacteria which cause mastitis on traditional farms, faecal and soil bacteria, indicate clearly that standards of hygiene could be improved.
Mastitis seems to be more frequent in animals with high milk yield, whether individuals, herds, breeds or species. This may have to do with the higher stress that the udder is exposed to when yielding more milk. It is quite clear however, that buffalo are less susceptible to mastitis than cattle. There might be both anatomical and physiological reasons for this. An Indian study cited in Ståhl Högberg and Lind (2003) compiled data on the incidence of mastitis in cows as well as in buffalo, see Table 10.
Mastitis can be clinical or sub-clinical. There is an important difference between these two. Sub-clinical mastitis may not even show. The observant milker may see slight changes in the milk such as the appearance of flakes, when fore milking into the strip cup. Sub-clinical mastitis shows up in the California mastitis test (CMT) and with increased counts of somatic cells in milk.
Acute mastitis is detected very easily. The udder is sore, swollen, hot and red. The buffalo is in pain when the inflamed quarter is touched. An inflamed quarter should be milked by hand very carefully, not forcing the milk out. This may be quite difficult, since the milk is thick (more like jelly) and may contain blood. The milk should not come into contact with any containers used for milking, nor animals or the floor. It should be discarded. The milker should carefully wash his hands before touching any other quarter, animal or equipment. Never milk an inflamed quarter with a machine!
Buffalo have a powerful defence against mastitis because of the anatomy of the teat. This starts with the teat skin, since buffalo teat skin is less sensitive than that of cow teats to chapping and sores. Inside the streak canal, the epithelium is thicker and more compact than in cattle. This gives extra resistance against the penetration of bacteria through the epithelium.
Furthermore, the keratin layer of the streak canal is thicker. The importance of the keratin layer is that it contains bactericidal and bacteristatic lipids and cationic proteins. The cationic proteins are inhibitory to the growth of Streptococcus agalactica and Staphylococcus aureus.
The sphincter of the streak canal is, as mentioned before, tighter than in cattle. It is also supplied with more nerve fibres and a richer blood vessel system than in cattle. This will help in maintaining a tight closure of the duct, limiting entry of bacteria into the mammary gland.
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| Testing for mastitis by checking somatic cell count with CMT. |
Measuring somatic cell count with
DeLaval cell counter DCC. |
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When the udder becomes infected or inflamed, the natural defence system goes into action to eliminate the infection or inflammation. Blood leukocytes, especially the phagocytes, migrate through the alveolar epithelium to the milk in order to remove the invading pathogens. Neutrophils are the most active leukocytes in this process. Lymphocytes and macrophages are also important in the udder defence system. Neutrophils, lymphocytes and macrophages together with epithelial cells are present in normal milk. In buffalo milk, several studies have revealed that the amount of neutrophils in total somatic cells (SCC) can be from 22-88% with an average of 56%. Lymphocytes are in the order of 10-54% (mean 28%). The occurrence of macrophages in buffalo milk is less than in cattle milk (8% vs. 30%). This massive attack by neutrophils is a powerful defense by the udder against invading pathogens.
Cell counts in milk from healthy buffalo varies between 50000 and 375000 per ml. This is comparable to cattle milk and the
difference therefore lies in the differential cell count as
described above. Studies indicate that the concentration and functional efficiency of phagocytes are superior in buffalo compared to cattle.
Mastitis disease is cured by antibiotics. Treating buffalo in the dry period with antibiotics in order to prevent the disease has been shown to be very effective. However, this can not be recommended since bacteria are known to develop resistance to antibiotics. Instead good methods for preventing the disease should be practiced. With training to detect mastitis during the early phase, spread of the disease can be prevented.
Machine milking has both been praised as the solution to mastitis problems and been cursed as the cause of mastitis. None of these extremes are completely true.
As stated previously, incorrect use of milking machines or milking with machines in poor condition may cause trauma to the teats. This in turn may lead to injuries like sores or chapping. The sores are readily invaded by pathogenic organisms and the disease becomes a fact. If a buffalo has got an infected quarter already, machines may aid in transmitting pathogens to the other quarters or to another buffalo. A fluctuating vacuum may cause milk to be pressed into the teat again, thus invading the teat with pathogens.
The machines themselves may also be a source for pathogens. Old liners and rubbers are easily cracked, and in these cracks micro-organisms are less susceptible to washing and detergents and may survive the cleaning. All these factors may easily be eliminated by good hygiene practices and by maintaining the equipment in good condition.
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