Bovine

mastitis Mastitis is inflammation of the breast or udder, usually associated with breastfeeding. Symptoms typically include local pain and redness. There is often an associated fever and general soreness. Onset is typically fairly rapid and usually occurs ...

is the persistent, inflammatory reaction of the

udder An udder is an organ formed of two or four mammary glands on the females of dairy animals and ruminants such as cattle, goats, and sheep. An udder is equivalent to the breast in primates and elephantine pachyderms. The udder is a single mass han ...

tissue due to physical trauma or microorganisms infections.

Mastitis Mastitis is inflammation of the breast or udder, usually associated with breastfeeding. Symptoms typically include local pain and redness. There is often an associated fever and general soreness. Onset is typically fairly rapid and usually occurs ...

, a potentially fatal

mammary gland A mammary gland is an exocrine gland in humans and other mammals that produces milk to feed young offspring. Mammals get their name from the Latin word ''mamma'', "breast". The mammary glands are arranged in organs such as the breasts in ...

infection An infection is the invasion of tissues by pathogens, their multiplication, and the reaction of host tissues to the infectious agent and the toxins they produce. An infectious disease, also known as a transmissible disease or communicable di ...

, is the most common

disease A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism, and that is not immediately due to any external injury. Diseases are often known to be medical conditions that a ...

dairy cattle Dairy cattle (also called dairy cows) are cattle bred for the ability to produce large quantities of milk, from which dairy products are made. Dairy cattle generally are of the species '' Bos taurus''. Historically, little distinction was ...

in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country Continental United States, primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., ...

and worldwide. It is also the most costly disease to the

dairy industry A dairy is a business enterprise established for the harvesting or processing (or both) of animal milk – mostly from cows or buffaloes, but also from goats, sheep, horses, or camels – for human consumption. A dairy is typically located on ...

Milk Milk is a white liquid food produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals (including breastfed human infants) before they are able to digest solid food. Immune factors and immune-modulat ...

from cows suffering from mastitis has an increased

somatic cell count A somatic cell count (SCC) is a cell count of somatic cells in a fluid specimen, usually milk. In dairying, the SCC is an indicator of the quality of milk—specifically, its low likeliness to contain harmful bacteria, and thus its high food s ...

. Prevention and control of mastitis requires consistency in sanitizing the cow barn facilities, proper milking procedure and segregation of infected animals. Treatment of the disease is carried out by penicillin injection in combination with sulphar drug

Definition

Mastitis occurs when

white blood cells White blood cells, also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from mult ...

(leukocytes) are released into the

, usually in response to

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one biological cell. They constitute a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria were am ...

invading the teat canal or occasionally by

chemical A chemical substance is a form of matter having constant chemical composition and characteristic properties. Some references add that chemical substance cannot be separated into its constituent elements by physical separation methods, i.e., w ...

, mechanical, or thermal trauma on the udder.

-secreting tissue and various ducts throughout the mammary gland are damaged due to

toxin A toxin is a naturally occurring organic poison produced by metabolic activities of living cells or organisms. Toxins occur especially as a protein or conjugated protein. The term toxin was first used by organic chemist Ludwig Brieger (1849 ...

s released by the bacteria resulting in reduced milk yield and quality.

Identification

This disease can be identified by abnormalities in the udder such as swelling, heat, redness, hardness, or pain (if it is clinical). Other indications of mastitis may be abnormalities in milk such as a watery appearance, flakes, or clots. When infected with sub-clinical mastitis, a cow does not show any visible signs of infection or abnormalities in milk or on the udder.

Mastitis-causing bacteria

Bacteria that are known to cause mastitis include: These bacteria can be classified as environmental or contagious depending on mode and source of transmission.

Types of mastitis

Mastitis may be classified according two different criteria: either according to the clinical symptoms or depending on the mode of transmission. ;Clinical symptoms * Clinical mastitis : The form in which macroscopic changes in the milk and udder of the milch animal is easily detectable by the milker. * Sub-Clinical mastitis : The form in which the milk and udder of the milch animal appear normal and can be diagnosed by testing of milk samples for various compositional changes and presence of pathogens and somatic cells. * per acute mastitis * acute mastitis * sub acute mastitis * chronic mastitis : This form includes no pain in the udder but little compositional changes in the milk. ;Mode of transmission * Contagious mastitis also known as bovine mastitis * Environmental mastitis * Summer mastitis (which occurs in summer months in heifers or unmilked cows)

Transmission

Mastitis is most often transmitted by repetitive contact with the

milking machine Milking is the act of removing milk from the mammary glands of cattle, water buffalo, humans, goats, sheep, and, more rarely, camels, horses and donkeys. Milking may be done by hand or by machine, and requires the animal to be currently or recen ...

, and through contaminated hands or materials. Another route is via the oral-to-udder transmission among calves. Feeding calves on milk may introduce some mastitis causing bacteria strain in the oral cavity of the calf where it will stay dormant until it is transmitted elsewhere. Since grouped calves like to stimulate suckling, they will transmit the bacteria to the udder tissue of their fellow calves. The bacteria will lay dormant in the udder tissue as the calf grows until it begins to lactate. That is when the bacteria activates and causes mastitis. This calls for stric
calf management practices
to curb this route of transmission. Micro-organisms enter through the

teat A teat is the projection from the mammary glands of mammals from which milk flows or is ejected for the purpose of feeding young. In many mammals the teat projects from the udder. The number of teats varies by mammalian species and often corr ...

tip into the teat duct where they get colonized due to the presence of leftover milk in the duct and subsequently spread throughout the udder causing infection. The effect of unhygienic milking machines and incomplete milking can help in this infection.

Effects on milk composition

Mastitis can cause a decline in

potassium Potassium is the chemical element with the symbol K (from Neo-Latin '' kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmos ...

and an increase in

lactoferrin Lactoferrin (LF), also known as lactotransferrin (LTF), is a multifunctional protein of the transferrin family. Lactoferrin is a globular glycoprotein with a molecular mass of about 80 kDa that is widely represented in various secretory fluids, s ...

. It also results in decreased

casein Casein ( , from Latin ''caseus'' "cheese") is a family of related phosphoproteins ( αS1, aS2, β, κ) that are commonly found in mammalian milk, comprising about 80% of the proteins in cow's milk and between 20% and 60% of the proteins in hum ...

, the major

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

in milk. As most

calcium Calcium is a chemical element with the symbol Ca and atomic number 20. As an alkaline earth metal, calcium is a reactive metal that forms a dark oxide-nitride layer when exposed to air. Its physical and chemical properties are most similar ...

in milk is associated with casein, the disruption of casein

synthesis Synthesis or synthesize may refer to: Science Chemistry and biochemistry * Chemical synthesis, the execution of chemical reactions to form a more complex molecule from chemical precursors **Organic synthesis, the chemical synthesis of organ ...

contributes to lowered calcium in milk. The milk protein continues to undergo further deterioration during processing and storage. Milk from cows with mastitis also has a higher somatic cell count. Generally speaking, the higher the somatic cell count, the lower the milk quality. It also has a high microbial count. This reduces it's yield.

Constituents with increased constitution

The levels of total whey proteins (Mainly

bovine serum albumin Bovine serum albumin (BSA or "Fraction V") is a serum albumin protein derived from cows. It is often used as a protein concentration standard in lab experiments. The nickname "Fraction V" refers to albumin being the fifth fraction of the origi ...

immunoglobulins An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...

) (Na and Cl ions) and other ions (Cu, Fe, Zn) various enzymes and certain

glycoprotein Glycoproteins are proteins which contain oligosaccharide chains covalently attached to amino acid side-chains. The carbohydrate is attached to the protein in a cotranslational or posttranslational modification. This process is known as glyco ...

s increase significantly. The pH of the milk increases too. Enzymes namely

protease A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the ...

lipase Lipase ( ) is a family of enzymes that catalyzes the hydrolysis of fats. Some lipases display broad substrate scope including esters of cholesterol, phospholipids, and of lipid-soluble vitamins and sphingomyelinases; however, these are usually ...

aldolase Fructose-bisphosphate aldolase (), often just aldolase, is an enzyme catalyzing a reversible reaction that splits the aldol, fructose 1,6-bisphosphate, into the triose phosphates dihydroxyacetone phosphate (DHAP) and glyceraldehyde 3-phospha ...

sorbitol Sorbitol (), less commonly known as glucitol (), is a sugar alcohol with a sweet taste which the human body metabolizes slowly. It can be obtained by reduction of glucose, which changes the converted aldehyde group (−CHO) to a primary alcoho ...

dehydrogenase A dehydrogenase is an enzyme belonging to the group of oxidoreductases that oxidizes a substrate by reducing an electron acceptor, usually NAD+/NADP+ or a flavin coenzyme such as FAD or FMN. Like all catalysts, they catalyze reverse as well as ...

also get increased.

Constituents with decreased constitution

The levels of

lactose Lactose is a disaccharide sugar synthesized by galactose and glucose subunits and has the molecular formula C12H22O11. Lactose makes up around 2–8% of milk (by mass). The name comes from ' (gen. '), the Latin word for milk, plus the suffix ' ...

, fat, total

(alpha and beta fractions decrease but gamma fraction increase ) some whey proteins (

alpha-lactalbumin Lactalbumin, alpha-, also known as LALBA, is a protein that in humans is encoded by the ''LALBA'' gene. Overview α-Lactalbumin is a protein that regulates the production of lactose in the milk of almost all mammalian species. In primates, alp ...

and

beta-lactoglobulin β-Lactoglobulin (BLG) is the major whey protein of cow and sheep's milk (~3 g/L), and is also present in many other mammalian species; a notable exception being humans. Its structure, properties and biological role have been reviewed many time ...

) potassium and other minerals (Ca, Mg, P) decreases. Mastitic milk generally has lower SNF (solid-not-fat).

Xanthine oxidase Xanthine oxidase (XO, sometimes XAO) is a form of xanthine oxidoreductase, a type of enzyme that generates reactive oxygen species. These enzymes catalyze the oxidation of hypoxanthine to xanthine and can further catalyze the oxidation of xanthin ...

reduces by nearly half.

Detection

California Mastitis Test Schalmtestplatte

Cattle affected by mastitis can be detected by examining the udder for inflammation and swelling, or by observing the consistency of the milk, which will often develop clots or change color when a cow is infected. Another method of detection is the

California mastitis test The California mastitis test (CMT) is a simple cow-side indicator of the somatic cell count of milk. It operates by disrupting the cell membrane of any cells present in the milk sample, allowing the DNA in those cells to react with the test reage ...

, which is designed to measure the milk's

as a means for detecting inflammation and infection of the udder. The pH value of mastitic milk is higher than that of normal milk. On mixing 5ml of milk with 1 ml of bromothymol blue, the appearance of blue green colour indicated mastitic milk which has a pH of 6.8 or more as against the grass green colour produced by normal milk that has a pH of 6.6. Normal milk has a chloride content of 0.08 to 0.14% whereas abnormal milk has more than 0.14%. The chloride content of milk can be estimated by addition of

silver nitrate Silver nitrate is an inorganic compound with chemical formula . It is a versatile precursor to many other silver compounds, such as those used in photography. It is far less sensitive to light than the halides. It was once called ''lunar causti ...

solution and 2 to 3 drops of potassium chromate as an indicator, A yellow colour indicates that the milk is abnormal.

Catalase test Catalase is a common enzyme found in nearly all living organisms exposed to oxygen (such as bacteria, plants, and animals) which catalyzes the decomposition of hydrogen peroxide to water and oxygen. It is a very important enzyme in protecting t ...

is also used to detect catalase which is present only in mastitic milk. Resazurin

rennet Rennet () is a complex set of enzymes produced in the stomachs of ruminant mammals. Chymosin, its key component, is a protease enzyme that curdles the casein in milk. In addition to chymosin, rennet contains other enzymes, such as pepsin an ...

test is based on the disturbance in the salt balance and increase in leucocyte content in mastitic milk. Coagulation of milk by rennet is sowed down due to disturbed salt balance and leucocytes reduce resazurin dye faster. Mastitic samples give delayed coagulation but faster resazurin reduction compared to normal milk

Treatment

Treatment is possible with

antibiotics An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and preventio ...

- such as penicillin, but milk from such cows is not marketable until drug residues have left the cow's system. Antibiotics may be systemic (injected into the body), or they may be forced upwards into the teat through the teat canal (intramammary infusion). Cows being treated may be marked with tape to alert dairy workers, and their milk is syphoned off and discarded. To determine whether the levels of antibiotic residuals are within regulatory requirements, special

tests Test(s), testing, or TEST may refer to: * Test (assessment), an educational assessment intended to measure the respondents' knowledge or other abilities Arts and entertainment * ''Test'' (2013 film), an American film * ''Test'' (2014 film), ...

exist. Vaccinations for mastitis are available, but as they only reduce the severity of the condition, and cannot prevent reoccurring infections, they should be used in conjunction with a mastitis prevention program.

Control

Practices such as good

nutrition Nutrition is the biochemical and physiological process by which an organism uses food to support its life. It provides organisms with nutrients, which can be metabolized to create energy and chemical structures. Failure to obtain sufficient ...

, proper milking

hygiene Hygiene is a series of practices performed to preserve health. According to the World Health Organization (WHO), "Hygiene refers to conditions and practices that help to maintain health and prevent the spread of diseases." Personal hygiene refer ...

, and the culling of chronically infected cows can help. Ensuring that cows have clean, dry bedding decreases the risk of infection and transmission. Dairy workers should wear rubber gloves while milking, and machines should be cleaned regularly to decrease the incidence of transmission.

Prevention

A good milking routine is vital. This usually consists of applying a pre-milking teat dip or spray, such as an iodine spray, and wiping teats dry prior to milking. The milking machine is then applied. After milking, the teats can be cleaned again to remove any growth medium for bacteria. A post milking product such as iodine-propylene glycol dip is used as a disinfectant and a barrier between the open teat and the bacteria in the air. Mastitis can occur after milking because the teat holes close after 15 minutes if the animal sits in a dirty place with feces and urine.

Industry costs

This disease costs the US dairy industry about 1.7 to 2 billion USD each year.

References

External links

UC Davis fact sheetNMC - Global organization for mastitis control and milk quality
{{DEFAULTSORT:Mastitis In Dairy Cattle Dairy farming Bovine diseases