Pathology of the Mammary Gland Flashcards
Companion animals, neoplasia or mastitis?
Neoplasia
Farm animals,
neoplasia or mastitis?
Mastitis
What makes up the natural defense mechanisms of the mammary gland?
Teat orfice and canal make up the mechanical barrier
Lactoferrin, opsonins, and immunoglobins are …
Humoral factor defense mechanisms in milk
Where is mastitis the most costly Dz?
Dairy herds
Inflammation of the mammary gland is usually due to…
Infectious agents - mainly bacteria, some fungi - that gain access through the teat canal
Will you recognized a bacteria infection grossly?
YES! classically inflammation. With viral infections, we will not be able to see grossly
Hematogenous and percutaneous routes…
RARELY occur
When is it peak occurrence to have mastitis?
Shortly after calving and in the drying-off period when milk stagnates in the udder
What are the THREE CONTAGIOUS causes of mastitis?? KNOW THESE!!
Steptococcus agalactiae
Staphylococcus aureus
Mycoplasma spp
Which bacteria is this:
- Specific, contagious mastitis of ruminants; entry is through the teat canal
- Healing is characteristically by fibrosis; sequel = atrophy of quarters
- P is NOT systemically ill
Streptococcus agalactiae
Which bacteria is this:
- Acute inflammation due to an alpha-toxin; may be peracute and fulminating or milder or more chronic
- Abscesses, necrosis, gangrene in cattle
- P is systemically ill
Staphylococcus aureus
Which bacteria is this:
- Cattle and Sheep
- Galactogenic and hematogenous routes
- Sudden onset of agalactia, involvement of all 4 quarters, a precipitous drop in milk production, severe swelling of the udder, poor response to therapy and lack of obvious signs of systemic illness
- much more subtle
- Difficult to grown on culture
Mycoplasma bovis
Mycoplasma otitis can cause…
A head tilt
Where do Coliform mastitis occur?
Usually occur in places of poor hygiene. Once one is infected, may get severe metritis in the rest of the herd.
Why is it that E.coli may cause an acute and often fatal disease?
Potent endotoxin causes vascular damage leading to fluid exudates, hemorrhage, thrombosis and necrosis
What kind of cow does Coliform mastitis severely affected?
Newly calved cows transiently immunosuppressed
Per-acute cases of Coliform mastitis show…
systemic signs of severe toxemia
Mycobacterium bovis
Nocardia asteroids
Cryptococcus neoformans
ALL CAUSE…
Granulomatous mastitis
How is mycobacterium bovis spread?
Hematogenously, while the others are often reported to be iatrogenic
Which bacterial mastitis has been associated with Neomycin infusions in dry cows?
NOCARDIAL MASTITIS
Chronic inflammation of the lactiferous ducts and adjacent mammary gland has resulted in replacement of most of the gland by…
Pyogranulomas and Abscesses
Which bacteria usually causes mastitis in Ewe’s and Goats?
Staphylococcus aureus
Mannheimia haemolytica
What is Contagious Agalactia?
Primarily a Dz of goats, sheep being slightly less susceptible
What bacteria causes Contagious Agalactia?
Mycoplasma agalactiae
What infection are lactating females and kids particularly susceptible to and likely succumb in the septicemic phase of the disease?
Contagious agalactia
Can FMD cause mastitis?
YES!
What 2 viral disease cause mastitis?
Ovine Progressive Pneumonia (Maedi-Visna)
and
Caprine Arthritis Encephalitis (CAE)
What mammary gland neoplasia is common in rats?
Mammary Fibroadenomas
T of F:
Mammary tumors are seen most commonly in bitches and queens and are rare in other species
TRUE!
Are cats or dogs more likely to have a malignant mammary tumor?
CATS!
Ovariohysterectomy at an early age is well documented to significantly reduce the risk of mammary tumor development in dogs (risk of 0.5, 8, and 26% depending on whether ovariohysterectomy is performed before the 1st, 2nd, or 3rd estrus, respectively)
Spay your bitches, bitches!
Define Simple Adenoma of the mammary gland:
Proliferation of well differentiated luminal epithelial cells
Define Complex Adenoma of the mammary gland:
Mixed proliferation of secretory epithelial cells myoepithelial cells
What cells make up a fibroadenoma?
Epitheial and stroma cells
What makes up a benign mixed tumor?
Proliferation of glandular and mesenchymal elememts. These are usually hard.
Which malignant mammary tumor is the most common site of extraskeletal soft tissue in dogs?
Osteosarcoma
The younger the dogs are, the more likely they are to have…
Benign neoplasms than older dogs
Dogs who age is greater than 9.5…
Are more likely to have malignant neoplasms
T or F:
Dogs ovariectomised prior to the 4th estrus cycle are less likely to develop mammary neoplasms
TRUE
Dogs that have had their cycles manipulated with combinations of estrogens and proestrogens are more likely to have an increased number of…
Malignant neoplasms
Lymphatic invasion and lymph node metastasis are…
Significant prognostic factors
Feline mammary neoplasia is the _____ most common neoplasm in domestic cats.
Third most common neoplasm in domestic cats
What is the signal most important prognostic factor in cats?
TUMOR SIZE!
What was used years ago for behavior issues with cats?
Megestrol Acetate
What did the drug megestrol acetate cause in cats?
Mammary fibroadenomas – benign! due to prolonged progesterone therapy
Mammary Fibroadenomatous hyperplasia
AKA…
“Juvenile fibroadenoma
Feline mammary hypertrophy”
Histologically, with this tumor the stroma cells proliferate and take over. Which tumor is this?
Mammary Fibroadenoma— stoma cells will go back to normal count as soon as p is taken off drug causing this
