Slide Set 15: Mastitis

Question 1

What is mastitis?

Answer 1

inflammatory reaction of the udder’s tissue to bacteria, chemical, thermal or mechanical injury

Question 2

Describe the inflammatory response in mastitis

Answer 2

high levels of blood proteins and white blood cells in the mammary tissue and milk

Question 3

What is the purpose of an inflammatory response in mastitis?

Answer 3

destroy the microbes and repair the damaged tissue

Question 4

What are the types of mastitis?

Answer 4

1. infectious mastitis caused by microbes
   a. environmental mastitis caused by microbes in the environment
   b. contagious mastitis caused by microbes on or inside the udder
2. non-infectious mastitis caused by physical injury to the udder

Question 5

Describe the contagious mastitis

Answer 5

• caused by microbes live on the skin of the teat and inside the udder
• can be transmitted from one cow to another

Question 6

Describe the environmental mastitis

Answer 6

• caused by microbes that live in contaminated environment (e.g. water, feces)
• caused by mainly coliforms (e.g. e.coli)
• <10% of mastitis cases

Question 7

What are the 3 types of contagious mastitis?

Answer 7

• chronic mastitis
• clinical mastitis
• sub-clinical mastitis

Question 8

What are the 3 types of clinical mastitis?

Answer 8

• percute mastitis
• acute mastitis
• sub-acute mastitis

Question 9

Describe chronic mastitis

Answer 9

• A persistent infection of udder.
• Exists most of the time in the subclinical form.
• Occasionally can develop into the clinical form before returning to the subclinical.
• This results in hard lumps in the udder.

Question 10

Describe clinical mastitis

Answer 10

Clinical cases of mastitis are those where the cow displays definitive symptoms of the disease.

Question 11

Describe sub-clinical mastitis

Answer 11

the cow herself displaying no obvious clinical symptoms of the illness and no visible changes to the composition of her milk. These cases of mastitis are termed sub-clinical, and can be up to 40 times more common than clinical cases of the illness.

Question 12

Percute mastitis

Answer 12

Peracute mastitis is characterized by a sudden onset, severe inflammation of the udder, serous milk. Peracute mastitis can lead to agalactia. The inflammation may result from the organism itself, enzymes (from the tissue or the bacteria), toxins (endo or exo), or leukocyte products. The systemic illness is due to septicemia or toxemia, results in fever, anorexia, depression, decreased rumen motility, dehydration, and sometimes death of the cow. Systemic illness often precedes the symptoms manifested in the milk and mammary gland.

Question 13

Acute mastitis

Answer 13

Acute mastitis is characterized by a sudden onset, moderate to severe inflammation of udder, decreased production, and serous milk/fibrin clots. Systemic signs are similar but less severe than the peracute form.

Question 14

Sub-acute mastitis

Answer 14

Subacute mastitis is characterized by mild inflammation, there may be no visible changes in udder, there are generally small flakes or clots in the milk, and the milk may have an off-color. There are no systemic signs of illness.

Question 15

What are the causes of mastitis?

Answer 15

1. bacteria (S. agalactiae): the most common
2. milking machine
3. contaminated hands
4. contaminated cloth
5. coliforms
6. yeast and mycoplasma (overuse of antibiotics and poor sanitation (uncommon)

Question 16

S. agalactiae

Answer 16

• main cause of sub-clinical mastitis
• lives inside the udder
• spreads during milking

Question 17

S. aureus

Answer 17

• causes both clinical and sub-clinical mastitis
• lives inside and outside the udder on the skin
• more damaging (more potent toxins)

Question 18

Coliforms

Answer 18

• caused mainly by E-coli

- result from polluted water and feces

Question 19

True/False - Explain

Mastitic milk has higher protein levels

Answer 19

True

• the immune responds sends signals (cytokines) will increase the amount of Ig from the blood into the mammary epithelial cells as well as blood flow increase
• whey protein will be high in mastitis milk (low quality protein)

Question 20

What is the first sign of mastitis?

Answer 20

a milk clot

- it is basically a combination of dead epithelial cells, dead bacteria, and WBC as well as milk

Question 21

What happens in severe cases of mastitis?

Answer 21

the bacteria will start to enter the blood system and cause blood toxicity

Question 22

What are the factors affecting incidence of mastitis?

Answer 22

1. type of bacteria
2. stage of lactation
3. age of cow
4. inherited conformation of the cow
5. level of milk production
6. improper use of milking machine
7. environment

Question 23

How does the stage of lactation affect the incidence of mastitis?

Answer 23

most cases occur during the first 3 weeks of the dry period and the first month post-calving

Question 24

How does the age of the cow affect the incidence of mastitis?

Answer 24

older cows are more susceptible to mastitis to young cows

Question 25

How does the inherited conformation of the cow affect the incidence of mastitis?

Answer 25

- length of the legs relative to the size of the udder | - strength of the udder attachment

Question 26

How does the level of milk production affect the incidence of mastitis?

Answer 26

- no direct relation | - factors affecting milk tiled might affect mastitis

Question 27

How does the improper use of milking machine affect the incidence of mastitis?

Answer 27

- irregular fluctuation of the vacuum level | - or milking or incomplete milking

Question 28

How does the environment affect the incidence of mastitis?

Answer 28

- chilling of the udder in cold weather or cold ground - unclean bedding - improper housing as related to udder and teat injury

Question 29

What are the two types of somatic cells found in milk?

Answer 29

- leukocytes WBC (75%) - increases in response to infection or injury - Epithelial cells (25%) - increases as a result of infection or injury

Question 30

Somatic cell count and mastitis

Answer 30

- # of somatic cells indicate the severity of mastitis - can be expressed as Somatic Cell Count (SCC) or Somatic Cell Score (SCS) - normal milk contains <200,000 somatic cells/ml

Question 31

What are the tests that can be done to test for mastitis?

Answer 31

1. stip cup test 2. california mastitis test 3. Wisconsin tes 4. electronic somatic cell count

Question 32

Explain the California mastitis test

Answer 32

- test reagents react with nuclei of somatic cells to form a gel - the amount of gel formed is used to score mastitis - useful in detecting infection in each quarter - useful in case of sub-clinical and chronic mastitis

Question 33

Explain the Wisconsin test

Answer 33

- lab test conducted usually on bulk tank samples - reaction to reagents is measured and not estimated - goals according to WMT 1. Bulk tank reading <8mm (300,000 cells/ml) 2. Milk with score of 19mm (855,000 cells/ml) is considered unsuitable for human consumption

Question 34

Explain electronic somatic cell count

Answer 34

- automated system for somatic cell count - use by DHI service (e.g. VALACTA) - more accurate than CMT and WMT - can be used to monitor the udder's health of individual cows as well as that of herd - use the information from DHI report to milk loss due to subclinical mastitis

Question 35

What is the cost of mastitis?

Answer 35

- loss in milk (greatest loss) - change in milk quality and composition - cost of treatment - premature culling

Question 36

What can be done for control of mastitis?

Answer 36

- dry treatment - teat dripping - culling of chronically infected cows - proper milking hygiene - good nutrition - milking machine

Question 37

What is the treatment of mastitis?

Answer 37

- mastitis is treated with antibiotics - clinical mastitis successful in treating S. agalactiae successful rate for S. aureus sub-clinical mastitis treated with antibiotics during the dry-off period - treatment with vaccine - E.coli J5 vaccine (made from E.coli mutant strain) - vaccination against S.aureus made from 3 inactivated strains of S. aureus cure up to 60^of infected cows more efficient when administered with antibiotics

Question 38

What is the occurrence of mastitis in sow?

Answer 38

- around furrowing | - at weaning

Question 39

What are the reasons of mastitis in sow?

Answer 39

- due to bacteria gaining entry to the mammary gland | - flare-up of existing sub-clinical mastitis

Question 40

What are the causing agents of mastitis in sow?

Answer 40

- staphylococci and streptococci - coliform bacteria - miscellaneous bacteria

Question 41

Describe coliform mastitis of sow

Answer 41

- environmental mastitis (contamination with feces and urine) - caused mainly by E.coli

Question 42

Describe acute mastitis in sow (symptoms)

Answer 42

- reduced milk production - marked discolouration of skin over the udder - sick and very thin piglets

Question 43

Describe the Staphylococci and streptococci mastitis in sow

Answer 43

- less severe and less acute than environmental mastitis - occurs sporadically in one or more gland - may present in the gland in a subclinical form and then become clinical after furrowing - acute mastitis may be caused by staphylococci (exceptional cases). - the gland becomes swollen and the sow becomes sick

Question 44

Describe miscellaneous bacteria mastitis in sow

Answer 44

- caused by organisms such as pseudomonas - produce a serious mastitis and septicemia - often resistant to antibiotic treatment - infections are rare

Question 45

What are the symptoms of mastitis in sow?

Answer 45

- lack of appetite at furrowing - infected glands red, swollen, painful - discoloration of the mammary gland - refuse to suckle - fever and blue skin - piglets hungry, thin and squeal from lack of milk

Question 46

How is mastitis diagnosed in sows?

Answer 46

- clinical signs are usually sufficient to diagnose mastitis - a sample of the secretion from the infected quarters should be submitted to lab for examination - carried out by wiping the teat end with cotton wool soaked in surgical spirit, injecting the sow with 0.5ml oxytocin and once there is a good flow squirt the milk on to a sterile swab

Question 47

What are the problems with milk production after furrowing?

Answer 47

occurs in combination with mastitis 1. hypogalactia (reduction in milk production 2. agalactia (lack of milk production less frequent)

Question 48

What is the cause of agalactia?

Answer 48

- caused by inhibition of prolactin and oxytocin - toxin released into blood from mastitis inhibits the action of both hormones - other factors contributing agalactia include constipation and insufficient gut motility around the time of furrowing.

Question 49

What are the symptoms of agalactia?

Answer 49

- rapid breathing and depressed appetite - fever and reluctance to move around to allow nursing - infected glands will be enlarged and discoloured

Question 50

What is a plugged duct in humans?

Answer 50

- plugged duct is a sore tender lump or knotty area in the breast - occurs when milk duct is not draining well and inflammation builds up - a plugged duct is not accompanied by fever - if the plugged area is not drained, pressure can build up behind it and cause the surrounding tissue to become inflamed

Question 51

What is the occurrence of plugged duct in human?

Answer 51

- plugged duct occurs mostly in women with abundant milk | - more frequently during the early weeks of nursing and during winter months

Question 52

What are the contributing factors to plugged duct in human?

Answer 52

- anything that contribute to inadequate drainage of the milk ducts can increase the incidence of plugged ducts - missed or shortened feedings - factors that put pressure on the breast

Question 53

What is a caked duct in humans?

Answer 53

- if a large area of the breast is inflamed, hard and tender, it is sometimes referred as a "caked breast" - usually plugged or caked duct occurs only in one breast at a time.

Question 54

Describe mastitis in humans

Answer 54

- localized tenderness and heat together with systemic reaction of fever and sometimes nausea and vomiting - occurs mostly in one breast (staphylococcus) - may occur in both breasts (caused by staphylococci) - may occur in both breasts (caused by streptococci) two types: - lactational (most common) - non-lactational

Question 55

What is a subareolar abscess?

Answer 55

- the second most common breast infection - occurs when sebaceous glands around the nipple become infected. When this happens, an abscess will be formed - if the infection is detected early before the abscess is formed, it can often be treated with antibiotics - more often it may be necessary to make an incision and drain abscess

Question 56

What are breast lumps?

Answer 56

- most lumps are benign - found in both breasts - reasons include: normal changes in breast tissue, breast infection or injury and medicines that may cause lumps, changing estrogen and progesterone levels during menstrual cycle

Question 57

What are the 5 types of breast lumps?

Answer 57

- fibroadenomas - fibrocystic lumps - intraductal papilloma - traumatic fat necrosis - breast cancer

Question 58

Explain fibroadenomas

Answer 58

- the most common benign tumors - they are solid, rubbery lumps that move freely in the breast when pushed and usually painless - result from excess formation of lobules and surrounding breast tissue - occurs between age 20-30

Question 59

Explain fibrocystic lumps

Answer 59

- the most common breast disease between the age of 35 and 50 years - caused mainly by changes in hormones during normal monthly menstrual cycle - women with these lumps usually experience lumps in both breasts that increase in size and tenderness just prior to menstrual bleeding - the lumps are milk ducts and surrounding tissues that have grown and dilated to form cysts. - the cysts rapidly enlarge in response to hormones released near menstruation

Question 60

Explain intraductal papilloma

Answer 60

- small wart-like growth in the lining of the mammary duct near the nipple - usually affect women aged 45-50 and can produce bleeding from the nipple

Question 61

Explain traumatic fat necrosis

Answer 61

- occurs when there is trauma (sudden injury) to the breast | - causes fat to form in lumps which are generally round, firm, hard, and painless.

Question 62

What are the types of breast problems that can be seen in women?

Answer 62

- plugged duct - caked duct - subareolar abscess - benign breast lumps - breast cancer - mastitis

Question 63

What are the two types of lactational mastitis?

Answer 63

- cellulitis: an infection of the connective tissue | - adenitis: an infection of the milk duct

Question 64

What are the predisposing factors of mastitis in women?

Answer 64

- during breast feeding a woman's single nipple becomes cracked and sore allowing bacteria from the baby's mouth to enter the ducts - untreated plugged ducts or cracks in the nipple through which an infectious organism gains entrance to the breast tissue

Question 65

Explain non-lactational mastitis. Why does it occur?

Answer 65

- occurs in non-lactating women - in women who had lumpectomies followed by radiation therapy - in women with diabetes - in women whose immune systems are depressed - usually accompanied by high fever and headache and usually treated with antibiotics

Question 66

What are the reasons for milk stasis?

Answer 66

- frequency and duration fo feeds - ineffective suckling - blockage of milk duct - suboptimal attachment - overabundant milk supply

Question 67

Explain the pathophysiology of mastitis

Answer 67

LOCALIZED PATHOGENS - alter metabolic activity of mammary epithelial cells (decreased a-lactalbumin and b-lactoglobulin) - produce enzyme to decompose milk protein INFLAMMATORY CYTOKINES - Mediate nutrient change in nutrient transporter expression - Affect substrate availability to lactating epithelial cells INFLAMMATION TRIGGERS DAMAGE TO EPITHELIUM LAYER - Opening of tight junctions (decreased lactose, increased sodium) - increased oxidative stress (synthetic and secretory capacity)