Mastitis Control in Dairy Herd
Dr. Kedar Karki.
Background:
Mastitis is a sporadic problem in all species ‘it assumes major economic importance in dairy cattle and milking buffaloes. The economic loss it inflicts makes it the most important disease with which the dairy industry has to cope. Mastitis is an inflammatory condition of the udder resulting from invasion of pathogenic microorganisms through the teat canal. Mastitis is characterized by physical, chemical and microbiological changes in the milk and pathological changes in the udder. Milk from animals suffering from mastitis is unfit for human consumption. The market value of infected animals is seriously reduced because of severe destruction of glandular tissue of udder leading to loss of one or more quarters. Thus there is multifaceted economic loss to farmers due to discarded milk, reduced milk yield,decreased market value of animal and treatment costs.
Cause of Mastitis:
The major organisms causing mastitis in dairy cattle can be classified into two major classes:
1. Contagious organisms:
Contagious mastitis is most commonly caused by Staphylococcus aureus, and Streptococcus agalactiae. The usual source of contagious pathogens is infected glands of other cows and milker’s hand. Cow to Cow transmission occurs by contaminated common udder cloths, residual milk in teat cups and inadequate milking equipment. These organisms have been the primary targets of targets of traditional mastitis control programmes.
2. Environmental organisms:
The predominant organisms that cause environmental mastitis are Streptococcus spp, E.coli, Enterobactor spp, Pseudomonas spp, Nocardia spp. The usual source of these organisms is the environment of the cow. Inadequate management of the environment is principle mode of transmission. Environmental problems include wet bedding, dirty lots, milking wet udders, poor udder preparation, housing systems that lead treat injuries.
Categories of Mastitis:
• Clinical mastitis
It is characterized by abnormal texture and discoloration of milk, and by swelling, discoloration and increased temperature or pain of the gland It has four sub-categories:
Mild clinical mastitis.
Abnormalities are restricted to change in the milk.
a) Acute clinical mastitis.
It refers to distinct abnormalities in the milk with a hot, painful and swollen gland and systematic signs of fever, anorexia and decreased milk production.
b) Per acute clinical mastitis.
It rapidly shows severe systematic signs, perhaps even before changes are evident in milk. The udder is swollen and extremely painful.
c) Chronic clinical mastitis.
Commonly refers to a persistence and recurrence of change in the milk for long periods. The terms acute and chronic refers to the chronology of the clinical signs and not necessarily to the duration of the intramammary infection.
Sub-clinical mastitis.
It is defined as presence of pathogenic microorganisms in the milk and a somatic cell count above 500,000 cells/ml. There are no apparent clinical symptoms in affected cows and buffaloes.
Diagnostic Tests for Mastitis.
In mastitis control, diagnostic tests must be used to measure udder health status of milking cows and buffaloes .All diagnostic tests are subject to some limitations in their usefulness for determining the true status of the individual or herd. Similarly the implementation cost of a particular test into health management programme may be a limiting factor. Individuals involved in udder health management programme should understand the advantages and limitations of diagnostic methods and of the techniques used to evaluate their usefulness.
Principles of udder Health management Programmes:
Before taking up a mastitis control programme dedicated to promoting awareness about udder health status should be undertaken. In addition a good diagnostic system for the assessment of the udder health of individual cows and buffaloes herd must be available. With an awareness created and system of monitoring udder health in place, a potentially successful mastitis control program should be cost effective within the scope of average dairy producer’s management system and a visible success by the rapid reduction in number in numbers of clinical cases and by steady improvement in the parameters used for monitoring udder health status.
The udder health management programmed must be devised to fulfill following three basic principles
1. ELIMINATION OF EXISTING INFECTION.
2. PREVENTION OF NEW INFECTION.
3. MONITORING OF UDDER HEALTH STATUS.
Components of mastitis control programme.
An udder health management programme that fulfils the three basic principles must have following components.
Proper milking management methods.
The Proper milking management comprises premilking udder hygiene, stimulation of milk let down, and post milking teat disinfection. The following are the number of important steps to be followed in establishing a milking management routine.
A) Establish and maintain a regular milking schedule in a stress free environment.
B) Ensure that teats are clean and dry prior to milking.
C) Check foremilk and udder for mastitis.
D) Avoid over-milking.
E) Use an effective and safe post-milking teat germicide after every milking.
F) Establish milking order and segregation programme.
Dry cow udder health management.
Antibiotic therapy at the end of lactation has been one of the key steps in mastitis control programmes.
Dry cow treatment procedures should be carried out as follows:
a) Milk the udder out completely.
b) Immediately following teat cup removal dip all teats in an effective teat dip.
c) Allow the teat dip to dry.
d) Disinfect each teat end by scrubbing for few seconds with a alcohol soaked swab.
e) Infuse each quarter with single dose syringe of a recommended dry cow treatment. Use the partial insertion method of administration into the teat streak canal.
f) Dip all the teats in an effective teat dip immediately following treatment.
Dry cows should be provided clean and dry environment along with properly balanced ration.
Mastitis Treatment for lactating animals:
Another important step in the standard udder health management program is the early recognition and treatment of clinical mastitis. In conjunction with the producer, the herd veterinarian have to develop a treatment protocol for mastitis during lactation. The treatment progrmme that is developed must meet three criteria in order to be successful.
a) The therapeutic regimen must be efficacious in eliminating the organism and reducing the effect of endotoxins.
b) The regimen must be cost effective in terms of benefits gained verses cost of withheld milk and drug used.
c) Information regarding milk withholding periods should be available to help antibiotic residue risk for consumer.
Culling chronically infected milch animals:
Dairy herd culling is essentially an economic decision. Udder health status certainly can have an impact on the net present value of a particular milch animal thereby making it an important factor in removal decisions. Culling is an important step in control efforts for some specific mastitis pathogens.
Conclusion.
The establishment of realistic targets of performance for various udder health parameters is an important final step in an udder health management programme.These goals are important to determine whether there have been shortfalls in milk quality and udder health performance. The goal must be realistic and achievable,as well as economically viable.
A field approach to mastitis control in India
LATEST TRENDS IN THE TREATMENT AND CONTROL OF MASTITIS IN DAIRY ANIMALS
