MASTITIS IN DAIRY CATTLE-DETECTION, TREATMENT & PREVENTIVE MEASURES
Post no-1036 Dt 03/01/2019
Compiled & shared by-DR RAJESH KUMAR SINGH ,JAMSHEDPUR,JHARKHAND, INDIA, 9431309542,rajeshsinghvet@gmail.com
It is an inflammation of the udder/mammary gland almost always due to the effects of infection by bacterial or mycotic pathogens. Inflammation can be recognized by the following four characteristics:
Redness, Swelling, Heat, and Pain .
Inflammation caused by bacteria in the case of mastitis damage the udder tissue. Dead tissue and toxins released during inflammation cause adverse reaction to the body of the animal. Blood vessels will be damaged resulting in more blood flow to the affected area, which causes a more red color, and increase affected area. This causes a painful swelling due to accumulation of liquids and blood. The bacteria which cause Mastitis could be present and live literally everywhere in the dairy farms like on the stable floor, in dung, on the skin of cattle and on the milker’s hands. Dirty, warm and wet environments with plenty of food and water are favorable conditions for multiplication and survival of these microorganisms.
Factors that predispose to Mastitis
• Most important predisposing factor increasing the chance of mastitis is poor hygienic management. The presence of more bacteria around the area is the higher the chance of infection. There are other factors for the development of mastitis:
• Cattle with a high milk yield will develop mastitis more easily. Their udder tissue is more active and has longer milking time. This makes the teat canal open for a longer period of time. High milk production is also connected with more energy demand which possibly decreases resistance against infections.
• Poor milking technique: Force milking can cause injury to the teat and teat canal making the entrance of bacteria to the udder easier. Incomplete milking is another factor for multiplication of bacteria.
• Unhygienic milking procedure: lack of cleaning utensils, hand of the milker’s and the udder.
• Unhygienic housing system: Just after milking it takes about 20 minutes before the teat canal is fully closed so lack of clean floor and resting places increases the chance of gating mastitis.
• Teat injuries and teat sores: This could be due to different factors which lead to would formation on the teat.
• Exposure to environmental pathogens: Contamination of the environment where the dairy cattle lives by pathogenic bacteria which would enter the teat and cause mastitis.
Transmission of mastitis
The teat canal is the lowest part of the udder and easily in contact with sources of bacterial contamination like: the skin of the milkers hand, the skin of the cow, the dirt on the skin of the cow, the floor where the cow is standing/lying on, the milking bucket
Clinical signs of mastitis
Depending on the severity and stage of infection there are;
• Per acute mastitis: There is swelling, heat, pain, and abnormal secretion in the gland, accompanied by fever and other signs of systemic disturbance like depression, weakness, complete loss of appetite •
Acute/sub acute mastitis: Similar to per acute mastitis but the fever, loss of appetite, depression, systemic change and changes in the gland are slight to moderate
• Subclinical mastitis: The inflammatory reaction is detectable only through tests, the milk will not change visibly, but taste of milk will become salty.
• The most clear and often first sign of mastitis is characterized by the changes in the milk such as there can be flakes and lumps in the milk, color change of milk, the milk can become watery, instead of creamy yellow or blueish, milk can contain blood cloths and looks pink
Mastitis Detection Techniques
Strip cup technique
The strip cup has a black enameled plate and a cup. Milk the first three spades of milk from each quarter on the plate and checks for lumps, flakes and cloths. After testing store the milk in the cup and dispose in a proper hygienic way.
California Mastitis Test (CMT)
CMT is used to measure the status of udder for subclinical mastitis. It measures the amount of dead cells in the milk. There are always dead cells in the milk due to natural continuous renewal process in milk producing and other udder tissue. Under this condition the amount of dead cells are low and stay under 100,000 cells per milliliter of milk which is undetected by CMT. When there is a subclinical infection, the number of cells increases over 250,000 cells per milliliter of milk and changes will be detected with CMT.
Procedure of CMT:
1. Milk and discard the first three spades of milk from all four quarters
2. Take a few millilitres of milk from each quarter into different CMT rack quarters (petridishes can be used) and mark with its respective quarters.
3. Mix equal amount of CMT reagent with milk samples (T-pol and often normal dish wash detergent will also be suitable) to each rack quarters.
4. Stir gently and observe the following changes:
When milk is affected it will start to aggregate and become a gel.
More viscosity of the milk indicates more dead cells and severe subclinical infection.
Color change from purple to pink is also observed.
The milk will be thick and cloth.
Milk sample analysis
Milk sample analysis in the laboratory is important to identify the specific causative agent (bacteria) for the application of the right antibiotic therapy.
Procedure of milk sampling for laboratory analysis:
• First disinfect the teats with methylated spirit (alcohol over 80%) using a cotton gauze or when not available a clean cloth dissolved in alcohol.
• Use latex gloves. When not available wash your hand with detergents.
• Put milk in a sample bottle after milking away the first three spades of milk. This reduces the risk of contaminating the milk with bacteria around and in the teat canal.
• Close the bottle as soon as the milk is sampled.
• Mark a clear identification on the sample bottle. Use the name or Identification Card (ID) of the cow and write down from which quarter the sample was taken (left front (LF), right behind (RB), etc.)
• Bring the milk to the laboratory and store properly. Freezing is recommended for further laboratory examination if the first treatment has failed
Note: Taking a sample after administration of antibiotics will not give proper laboratory results.
Mastitis prevention and control measures
Prevention measures—-
Step 1: Check the milk equipment
• The milk equipment should be clean and dry. Buckets are preferably stored upside in the sun, so the inside will be dry and doesn’t give a suitable climate for bacterial multiplication.
Step 2: Clean the barn
• The cleaner the barn is, the fewer bacteria will be present. Avoid wet barn and keep clean and dry to reduce favourable condition for bacteria.
Step 3: Wash and dry your hands
• Most of the time hand of a milker is in touch with all kinds of objects contaminated with bacteria. So Proper washing and keeping dry their hands always is important to decrease bacterial contamination.
• Wash and keep dry the skin around the udder and teats before starting milking. This is important to remove contaminating microorganisms. When the cow is visibly clean, a dry paper towel will be sufficient.
Step 4: Check the first milk •
Use a strip cup and observe if the cow has mastitis infection or not.
Step 6: Milk the udder empty
• A good milking technique is crucial for the health of the teat. Complete milking has to be done gently not to injure the teats. Another important technique is a ‘full hand’ milking.
Step 7: Dipping the teat
By applying disinfectant to the teat after milking, bacteria can be removed while the teat canal is still open. This can be done commonly by dipping with an iodine solution in a dip cup as soon as possible after milking. This protects the teats from bacteria to enter the teat canal.
Step 8: Keep the cow standing
• It takes a few minutes for the teat canal to close properly. When a cow would lie down in this period on dirty floor bacteria will have the chance to enter the teat canal. Keeping cattle standing, for instance by offering them fresh feed, can reduce the risk mastitis infection.
Step 9: Clean the milking equipment
• Cleaning the milking equipment is also important reduce the bacterial contamination. Good cleaning consists of several aspects: ü First removal of dirt by brushing. The better and longer brushed the more dirt will be removed. ü Using detergents with hot water will help to dissolve the dirt. ü Removed detergent by rinsing with clean water. ü Treat milking utensils with disinfectants preferably chlorine solution. ü Then the utensils should be rinsed again dried by putting them upside down in the sun.
Note: – Bacteria cannot be killed by detergents; so disinfection is done only by disinfecting chemicals.
Treatment measures———–
Steps to be followed during treatment of mastitis
1st step:
Complete milking of affected cow • By milking the cow as often as possible, preferably every two hours; at least three times a day bacteria and dead cells are removed from the udder. This method is the best and very important to rinse away the infection.
2nd step: Disinfecting the teats • After milking the mastitis affected cows, their teats should be clean and disinfect with disinfectants like alcohol.
3rd step: Application of appropriate the drugs • Direct intramammary infusion of the special antibiotic tubes prepared for the treatment of mastitis twice a day for three consecutive days.
Note: • In case of systemic infection consult veterinarian for additional treatments like antibiotic injection or anti-inflammatory drugs to stop inflammation and reduce the pain. • Read the manufacturers leaflets for veterinary drugs to be used in dairy cattle concerning withdrawal periods for human consumption.
