CONCEPT OF MILKING MACHINE IN DAIRY CATTLE : (Modus operandi, Advantages & Disadvantages)
Dairy cattle are milked by machine. Milking machine design and function is critical for rapid and efficient removal of milk without damage to the teat or gland and with minimal risk for transmitting pathogenic microorganisms that might cause mastitis. The only way for mastitis-causing organisms to enter the teat is through the streak canal. This is the same route by which milk leaves the gland, therefore, anytime that the streak canal is opened to remove milk the gland is susceptible to potential intramammary infection.
Much of the recommended process of milking relates directly or indirectly to control and prevention of mastitis. The physical and functional interface between the teat and the machine are carefully designed to minimize the chances of intramammary infection occurring as a result of milking. Although the milking machine may only account for 5-10% of mastitis cases, proper milking machine function must be maintained over time. Incorrect vacuum or pulsator settings or worn teat cup liners all can enhance the role of the milking machine in contributing to intramammary infection.
The machine includes teat cups that contact the cow’s teats and remove the milk, a claw where milk pools as it is removed from the four teats, vacuum tubes that provide vacuum to the teat cups and a milk tube that removes milk away from the claw, a source of vacuum for the machine, and a pulsator that regulates the on-off cycle of the vacuum. Many milking machines today have an automatic take-off (ATO or detacher) device that removes the machine from the cow when milking is completed. In addition, many milking machine systems are linked to a computer system that both regulates the machine and generates data about the cow and its milk as milking is occurring..
Study (Brien et al. 2001) has shown that 33 per cent of net labour input per day in a dairying enterprise is associated with the milking process. Thus, it is appropriate to investigate the existing obstacles and limitations for efficient milking and also to investigate the role of technology in reducing the time associated with milking. Optimizing the use of labour is and will be one of the major challenges faced by dairy farmers.
The most corrective action which farmers can take to decrease labour demand is the adoption of milking machine. The adoption of milking machine is very mush influenced by the need to decrease the quantity of work involved in milking.
Advantages of Machine Milking:
- Large number of animals can be milked efficiently.
- Milking by machine saves time by almost half.
- Increases the rate of milking.
- Dependence on labour requirements reduced.
- Conductivity and temperature sensors attached to the machines can assist the dairymen in on line detection of sickness and estrus.
- Incomplete milking, poor hygiene etc. by hand can be avoided.
Needed: - Operator’s manual for the unit in use at the center.
- A double vat wash tank.
- Dairy detergent washing solution.
- Hot water.
- Brushes for each size of tube.
- Milking machine with double unit and complete outfit.
- Chlorine solution 200 ppm.
- Cows in milk (in good health).
- Three stop watches.
Procedure: - Hand milking methods:
(a) Full hand method called fisting.
(b) Stripping.
(c) Knuckling,
(Modern milking machine was invented by William Marchland of Scotland in 1889) - Machine milking:
Note:
Milking operation is one of the largest single labour requiring jobs of the dairy farm. With the increase in demand of milk more and more dairy farms are switching over to machine milking. Proper functioning of milking machine is essential not only to achieve milking performance but also to maintain udder health and quality of milk (Dang, 2001).
Following steps must be followed:
(a) Preparation for milking. This involves: - Getting milking barn/parlour clean, free of dust and bad odor.
- Assembling all equipment’s in the barn.
- Getting milkers and attendants ready for milking operations.
(b) Assembling the cows:
Get all cows tied or sanctioned a little before milking begins.
(c) Feeding:
If a practice of feeding concentrates to cow at milking time is being followed then it becomes a part of stimulus for “let down” of milk. Therefore cow must be given grains at milking time.
(d) Milking machine:
Landmarks in The Development Of Milking Machine
Landmarks in the evolution of marching machine have been given below chronologically:
I. 1830: 1st tube milking machine imitating hand milking developed.
II. 1851: Use of vacuum introduced milking machine.
III. 1860: First teat cup with vacuum milker developed.
IV. 1879: Used large gutta percha cup fitting to entire udder and connected with hand pump.
V. 1905: Two chamber teat cup invented.
VI. 1910: Electricity was used in milking machine for creating vacuum.
VII. 1930: First milking machine parlor introduced, which is comparable with any latest milking machine. - Number of milking machine units/milker:
Types of Milking Machine:
In India, two types of milking machine system are being generally used:
Partial Milking Machine System:
A partial system is commonly being used which is unhygienic for both the cattle and milk quality. Here, labour requirement is not significantly lowered leading to lower profitability. Moreover, this is also the main cause of disease transmission in the herd.
Automatic Machine System (AMS):
There will be pipeline system in which cows are milked in a milking parlor and milk flows directly to the central collection tank.
Guidelines to Use Milking Machine (Daisy et al. 2007):
Milking with the help of machine is a complex biological-technological process in which four factors are active: Man, Dairy cow. Machine and Environment. Collecting milk from a cow involves much more than a mechanical extraction. Most of the milk is accumulated within the alveoli of udder between milking.
The milk ejection reflex starts with the activation of nerves. During milking, as sight of a calf and touch of udder skin act as stimuli, sight and sound of milking machine also act as stimuli for letdown of milk. During milking machine, the flow rate may range from 2-5 kg of milk/min. for a period of 2 – 8 min. depending upon the milk yield. When milk flow stops, there is squawking of liner indicates the milking is completed.
Following steps are involved for proper functioning of milking machine:
- Pre-stimulation of teat.
- Teat cup attachment within one minute of teat dipping and drying.
- Adjustment of milking machine as per need.
- Shut down vacuum before removing tea cups.
- Application of sale and effective disinfectant on teat (Teat liner-kept in lye solution or commercial rubber cleaner after use, followed by acid rinse washing and proper drying).
Operational Norms of Milking Machine:
Optimum vacuum: 10-14 inch Hg (0.25 – 0.35 m Hg)
Pulsator rate: 45 – 65 times/min.
Pulsator ratio: 60: 40
Milk flow rate: 2-5 kg/min. for 2 – 8 min.
Disadvantages:
- It facilitates the entry of micro-organisms from exterior of teat to teat sinus during excessive vacuum fluctuation and by teat linear damage.
- There is chance of milk contamination from diseased udder due to common storage unit.
- In case of insufficient massage phase, over-milking and too high vacuum level lead to teat damage.
- There are cost-factor limitations in Indian conditions.
- Parts require careful attention with regard to cleaning:
The basic components of a milking machine include:
A Vacuum System:
Vacuum pump, Reserve tank, Vacuum regulator, Pipelines and long pulse tubes forming an enclosed space.
Pulsator:
This alters the vacuum level around the teat so that milking occurs without fluid congestion and oedema of the teat tissue.
Milking Unit or Cluster:
The assembly of four tea cups connected to a claw and mounted with a valve that admits and cuts off the vacuum to the unit.
Milk Removal System:
The system which transports the milk away from the milking unit: The milk tube and receiver (Bucket, Recording jar. Milk pipelines etc.).
All of the above components require a high degree of co-ordination for the milking machine to function properly.
a. Tea cups and inflations
b. Pails
c. Claws
d. Pail lids - Vacuum:
Milking machines operate on a negative pressure called vacuum which varies with different machine. The recommended vacuum is 10 to 15 inches. - Pulsation:
The recommended pulsation rate is about 50 per minute. The rate of pulsations is fixed in some machine but is adjustable in others, with speed of motor depending upon its make. - Preparation of Cows for milking:
(1) Prepare for let down:
Wipe and massage the udder and teats about half a minute prior to milking, using a clean duster soaked in antiseptic solution at warm water (55°C). Raj and Prasad (1983) reported benzytol (2% solution) as good udder wash in producing milk of low bacterial count.
(2) Draw out fore-milk:
Two streams of fore milk with full hand squeeze from each quarter must be drawn out into a strip cup.
This helps in the following:
(a) Enhances the “let down” of milk.
(b) Reduces the high bacteria count in milk (Lavania and Singh, 1973; Dey and Prasad, 1991).
(c) Detection of any abnormality with milk due to mastitis infection.
Note:
Milking operation can be faster and milk of udder can be withdrawn effectively only when milk ejection reflex is proper (Singh and Dang, 2002). - Care before Machine Milking:
a. Cleaning of animals by sprinkling of water before milking.
b. Cleaning of drying teats before milking.
c. Sufficient pre-milking stimulation by massage.
d. Observing the quality of fore milk.
e. Avoid machine milking when the animal is suffering from Mastitis.
f. Proper attachment of milking unit and alignment of tea cups.
g. Proper distributions of cluster weight overall the four teats.
h. Observing the animals for any behavioral changes.
i. Routine checking of SCC in milk.
j. Cleaning the milking parlor.
k. Follow the machine operating specifications before using.
l. Repairing, servicing, testing and changing the machine parts timely.
m. Put on teat-cup promptly after the cow is prepared for “let-down” of milk.
n. Don’t cause stimulus “let-down” too soon.
Routine of schedule for milking by Machine with two single units:
Step 1: Prepare first cow for milking as mentioned above.
Step 2: Prepare second cow also.
Step 3: Place teat-cups promptly on first cow, machine on.
Step 4: Place teat-cups on second cow, machine on.
Step 5: Prepare third cow for milking.
Step 6: Strip the first cow by machine and remove it.
Step 7: Empty the milk pail.
Step 8: Dip teat-cups in a pail of water for rinsing and then in a pail disinfecting chlorine solution of 200 ppm.
Step 9: Place the machine on third cow.
Step 10: Prepare fourth cow.
Step 11: Strip second cow and remove machine.
Step 12: Continue this routine for all the cows.
Limitations of Machine Milking:
Improper machine milking may lead to tissue erosion and cause migration of polymorphonuclear leucocytes from blood into mammary lymph and milk. Teat erosion further allows organisms to grow, thus increasing the chance of new udder infections.
Milking machine may influence the incidence of udder infection rate (Spencer, 1989) by acting as a carrier of pathogens from one cow to the next; it can also serve as a path; it can also serve as a pathway of cross infection within cows.
Advantages of Machine Milking:
a. Large number of animals can be milked efficiently.
b. Milking by machine saves time by almost half.
c. Increases the rate of milking.
d. Dependence on labor requirements reduced.
e. Conductivity and temperature sensors attached to the machines can assist the dairymen in on line detection of sickness & estrus.
f. Incomplete milking poor hygiene etc. by hand can be avoided.
Guidelines to Use Milking Machine :
Milking with the help of machine is a complex Biological-technological process in which four factors are active: Man, Dairy cow, Machine and Environment. Collecting milk from a cow involves much more than a mechanical extraction. Most of the milk is accumulated within the alveoli of udder between milking.
The milk ejection reflex starts with the activation of nerves. During milking, as sight of a calf and touch of udder skin act as stimuli, sight and sound of milking machine also act as stimuli for letdown of milk. During milking by milking machine, the flow rate may range from 2-5 kg of milk/min. for a period of 2-8 min. depending upon the milk yield. When milk flow stops, there is squawking of liner which indicates the milking is completed.
Following steps are involved for proper functioning of milking machine:
a. Pre-stimulation of teat
b. Teat cup attachment within one minute of teat dipping and drying
c. Adjustment of milking machine as per need
d. Shut down vacuum before removing tea cups
e. Application of safe and effective disinfectant on teat.
Precaution:
Care Before Machine Milking: - Cleaning of animals by sprinkling of water before milking.
- Cleaning of drying teats before milking.
- Sufficient pre-milking stimulation by massage.
- Observing the quality of fore milk.
- Avoid machine milking when the animal is suffering from Mastitis.
- Proper attachment of milking unit and alignment of tea cups.
- Proper distribution of cluster weights overall the four teats.
- Observing the animals for any behavioral changes.
- Routine checking of SCC in milk.
- Cleaning the milking parlor.
- Follow the machine operating specifications before using.
- Repairing, servicing, testing and changing the machine parts timely.
- Put on teat-cup promptly after the cow is prepared for “let-down” of milk.
- Don’t cause stimulus “let-down” too soon.
Care During Machine Milking:
(a) Precise and regular pulsation of machine.
(b) Checking the vacuum level and any air leakage.
(c) Proper handling of milking unit.
(d) Preventing tea cups from coming in contact with contaminated material like dung, urine, dist, etc.
(e) Do not allow tea cups to remain on too long as the teats at their opening may become eroded and hard causing teat erosion.
(f) Do not operate machine with excessive vacuum than the recommend one as it will cause injury on the lining of teat cistern.
Care After Machine Milking:
(i) Automatic cluster removal at the appropriate time and in a current way.
(ii) Post milk teat dipping with iodophores or antiseptic solutions.
(iii) Milking sick animals lastly and discarding milk from mastitis infected animals,
(iv) Cleaning of the milking unit after milking.
(v) Don’t make incomplete milking of any quarter as the milk left in the quarter predisposes it to mastitis infection and overall yield of milk may also be less. Give special attention to those quarters which do not milk out as readily as others.
Follow principles of good milking. These are as follows:
The principle of machine milking differs from the principle of hand milking and sucking. During hand milking, the milk is pressed out, while during sucking, the milk is mainly pressed and to some extent sucked out. During machine milking the milk is sucked out by a difference in pressure between the inner wall of the liner and udder. Therefore, the milking machine is fabricated in such a way so that sucking is interrupted by rhythmical motion (opening and closing) of the liner.
Consequently, the teats are exposed to massage and congestion in the teat end is prevented:
(a) Short interval between two milking.
(b) Equal interval between all milking.
(c) Avoid excitement of cows and follow quiet milking.
(d) Uninterrupted or continuous milking.
(e) Complete milking from all quarters of udder.
(f) Uniform milking.
(g) Rapid milking.
(h) Milking at the same time every day.
(i) Prepare the cow for let down by wiping udder and teats with clean cloth soaked in warm antiseptic solution (55″C).
(j) Draw out two or three streams of foremilk from each quarter and check on strip cup for any abnormality.
(k) Remove the teat-cups as soon as milk ceases to flow.
(l) Strip the cow clean while machine is on.
Note: - It is advisable to use a milking machine in farms with at least 8 to 10 high yielding cows or more. If the herd size exceeds 100 cows, construction of a separate milk parlor is desirable.
- In case of hand, milking always is done with clean and dry hands.
- Teats of cows for machine milking must be of convenient size to fit in teat-cups.
- The entire milking operation must be completed within seven minutes because of “Let down” effect of oxytocin hormone secreted by posterior pituitary gland. This remains in blood for nearly 8 minute.
- Time Saving:
The number of animals milked per hour per milkier at one time is one of the most important parameters to use milking machine. The speed with which a cow is milked is of great economic importance in the dairy farm operation.
Many researchers (Joshi, et al, 1992 and Singh and Dave, 1994) clearly indicated that milking machine takes less time than hand milking. Using a milking machine 1 person can milk 20 cows in 15 min., whereas in hand milking, 2 people can milk 20 cows in 2 hrs. 30 min. Josh et al., (1992) also recorded an average time of 0.98 min for milking each kg in milking machine and 3.23 min. in hand milking.
Miscellaneous:
Milking of hard milkier cow is always a great problem as it needs an experienced person. Therefore, avoidance of hard milkier cows in a Hand milking is overcome by milking machine.
Compiled & Shared by- Team, LITD (Livestock Institute of Training & Development)
Image-Courtesy-Google
Reference-On Request.
