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286 Cards in this Set
- Front
- Back
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what are the main organs of the hemolymphatic system?
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lymph nodes, spleen, thymus
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an antigenic stimulation can cause what effect on lymph nodes?
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hyperplasia
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what are the two main rule-outs for generalized lymphadenopathy?
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1. neoplasia
2. systemic infection |
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what is the gross appearance of a hyperplasic lymph node versus a neoplastic lymph node?
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hyperplastic is mottled, whereas a neoplastic lymph node is homogeneous
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how do hyperplastic lymph nodes differ from neoplastic lymph nodes upon palpation?
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hyperplastic lymph nodes can be painful or tender, whereas neoplastic lymph nodes are not painful
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what three things are usually seen histologically in hyperplastic lymphadenopathy?
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1. histiocytosis of the sinuses
2. plasma cell proliferation 3. enlargement and increased activity in the lymphoid follicular areas |
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focal hyperplastic lymphadenopathy (few regional nodes) is usually indicative of what?
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localized invaders/insults
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in what species can senile atrophy of lymphoid tissue be seen?
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horses and dogs
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what would be the rule-out for a shrunken spleen with a thick capsule and shrunken lymph nodes?
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senile atrophy
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if you find a darkly-colored lymph node, what could it be?
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1. a hilar lymph node near the lung or a mesenteric lymph node (which are commonly dark all of the time)
2. hemorrhagic lymphadenopathy 3. anthracosis |
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what is the pathological condition of hemorrhage into lymph nodes called? what is commonly seen histoloigcally?
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hemorrhagic lymphadenopathy
- erythrophagocytosis - hemosiderin deposition |
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the presence of foreign pigments or substances in the lymph nodes
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anthracosis
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inflammation of the lymph nodes
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lymphadenitis
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caseous lymphadenitis of sheep and goats is indicative of what disease?
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Corynebacterium pseudotuberculosis
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ulcerative lymphangitis of cattle and horses is indicative of what disease?
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Corynebacterium pseudotuberculosis
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Corynebacterium pseudotuberculosis
- appearance of lesion in lymph nodes - how long can organism survive in the environment? - virulence factors - route of infection - clinical signs - organs affected |
The lesions appear as caseous lymphadenitis (sheep & goats) or ulcerative lymphangitis (cattle and horse). In sheep, they have an onion-like appearance. This does not happen in goats
The bacteria can survive up to 5 months in the environment The organism has an exotoxin that increases vascular permeability and a leukotoxic surface lipid. Infection is usually through a surface wound (e.g. shearing in sheep) Chronic wasting is a clinical sign; often comorbid with retroviral infection In goats, affects lymph nodes in the head and neck; in sheep, affects dermal, prescapular, or crural lymph nodes Infection can spread to lung, liver, spleen, and kidney |
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purulent lymphadenitis with green, odorless pus in horses, swine, and dogs is due to what?
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streptococcal infection
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what is "strangles" in puppies and horses?
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purulent lymphadenitis due to streptococcal infection.
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what are "bastard strangles" in horses?
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purulent lymphadenitis that has spread to develop internal abscesses
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infiltration of the lymph nodes with macrophages
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granulomatous lymphadenitis
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what are three important rule-outs for granulomatous lymphadenitis?
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1. tuberculosis
2. histoplasmosis 3. leishmaniasis |
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granulomatous lymphadenitis is also accompanied by what pathologic condition of the hemolymphatic system?
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splenomegaly
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what is the difference between lymphoma and leukemia?
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lymphoma: no neoplastic cells are circulating
leukemia: neoplastic cells are circulating |
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leukemia with significant bone marrow neoplasia will typically show what three things in a CBC?
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1. anemia
2. thrombocytopenia 3. neutropenia |
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any type of primary neoplastic disorder of the hemolymph system is called what?
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lymphoma
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lymphoma:
- appearance of lymph nodes - which nodes are affected - etiology |
- Lymph nodes appear tan/gray with no mottling and are usually homogeneous, large, soft, and pale
- usually disseminated in multiple nodes - in cats and cows, usually associated with a retrovirus; other species, it is unclear |
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what is the histologic pattern of small lymphocyte lymphoma?
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small cells with scant, basophilic cytoplasm. Rare mitoses. Dark nuclei with little evidence of nucleoli or other structures. Slowly growing.
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what is a common clinical sign seen in dogs with lymphoma and why?
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hypercalcemia is commonly seen because the lymphoma is secreting a parathormone-like hormone.
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acute lymphocytic leukemia
- common species and age - etiology - how do lymph nodes appear? |
- cats and calves under 1 year; dogs under 5 years
- associated with a virus in cats, but not in calves - lymph nodes are not enlarged; usually bone marrow involvement |
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chronic lymphocytic leukemia
- species - pathological findings |
- cats, cattle, dogs 8 years and older
splenomegaly, profound lymphocytosis, moderate anemia; infiltrated liver is pale with a reticulated pattern |
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a lymphoma with neoplasms resembling plasma cells is likely what?
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secretory/non-secretory immunoblastic sarcoma
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what pathological signs would be expected with secretory immunoblastic lymphoma?
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- lysis of flat bones due to metastasis to bone marrow
- monoclonal gamma-globulin spike (neoplastic immunocytes don't shut off antibody secretion) - hyperviscous blood - irreversible hypotension during surgery - splenomegaly with splenic infarcts |
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a neoplastic disease involving small, round, hard plaques within the skin.
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cutaneous lymphoma
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cutaneous lymphoma:
- lesions - species - speed of disease |
- small, round, hard plaques within the skin
- dogs, horses, and other spp. - slowly-progressing disease; can take years for the disease to become fulminate |
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which disorders can occur as a result of a congenital thymic aplasia or hypoplasia? Where is this most common?
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- t-cell disorders
- b-cell disorders - combined immunodeficiency, CID (both t- and b-cell disorders) most commonly found as CID in Arabian foals as a recessive disease. |
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which hemolymphatic syndrome is common to Arabian foals and how will it present on pathological examination?
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CID (combined immunodeficiency)
foal will present with a congenitally small thymus, lymph nodes, and spleen, and will have virtually no circulating lymphocytes of either lineage. |
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an Arabian foal dies of adenoviral pneumonia. What congenital disease is on your rule-out list?
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CID
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a large swelling of the thymus in the neck of Nubian goat kids. Comment on the pathology.
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"milk goiter"
This is not pathologic. "Too much thymus doesn't hurt anything" |
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what is "milk goiter?"
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In Nubian goat kids, a large thymus that protrudes through the thoracic inlet and causes large swellings in the neck. This is normal and not a pathological condition.
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what are two examples of inflammatory changes of the thymus? What does the thymus look like in these diseases?
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1. foals with rhinopneumonitis (equine herpesvirus) abortion. Thymus will have necrotizing lesions with prominent intranuclear inclusions typical of a herpesvirus.
2. cats with panleukopenia. They will present with thymic atrophy |
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what are the two basic consequences of thymic neoplasia?
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1. space occupying tumor can compromise normal respiration and cardiovascular function
2. metathesis |
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what are the two basic types of thymic neoplasias and are they malignant or benign?
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1. thymomas - benign
2. thymic lymphomas - malignant |
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what are the two types of thymomas? How do they appear histologically?
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1. lymphoid thymoma - comprise mostly lymphoid cells but include some epithelial component
2. lymphoepithelial thymoma - a sheet of lymphocytes with scattered tight whorls of epithelial cells |
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thymic lymphoma
- benign or malignant? - species - clinical presentation |
- malignant
- dog, cat (30% of all feline lymphomas), calves cats: acute respiratory distress calves: huge masses on the ventral neck; compress the lungs and vascular structures; vascular return to the heart is compromised |
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lymphoid thymoma
- benign or malignant? - species - clinical presentation |
- benign
- dog, sheep, goat, (rarely) horse - firmly encapsulated lesions that cause problems because of their space-occupying nature |
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lymphoepithelial thymoma
- benign or malignant? - species - clinical presentation |
- benign
- sheep and goat (and other species) - encapsulated lesions; associated with myasthenia gravis in the dog |
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what is the most common congenital abnormality of the spleen? Species differences?
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congenital extra spleens
- pig: common - calves and lambs: part of a syndrome of congenital defects leading to a nonviable fetus |
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what are two major ways in which extra spleens can occur in an animal?
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1. congenital
2. post trauma |
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what are three presentations of a degenerative spleen? comment on prevalence
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senile atrophy and amyloidosis - rare
siderotic plaques - common |
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grey or tan fibrogranulomatous capsular lesions on the spleen of the dog
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siderotic plaques
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what are siderotic plaques?
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in the dog, degenerative accumulations of fibrous tissue, macrophages, hemosiderin, and mineral in the splenic capsule. Most likely the result of the end-stage of capsular hemorrhage.
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what are the three main causes of splenomegaly?
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1. congestion
2. infiltration 3. neoplasia |
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what are three rule-outs for congestive splenomegaly?
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1. gastric/gastrosplenic torsion - pigs and dogs
2. systemic bacterial infection (e.g. anthrax) 3. barbiturate anesthesia/euthanasia |
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what are four rule-outs for splenic infarcts?
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1. forestomach disease (ulcers/trauma) - cattle
2. abscesses - horses 3. hog cholera - (rare) 4. left-sided vegetative endocarditis |
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anthrax
- where in the environment? - infective form - clinical presentation - species susceptibility |
- found in alkaline soils with decaying vegetation
- spores are infective; vegetative are not - lymphadenitis and lymphangitis (except dogs and pigs) - very little inflammatory response - generalized hypocoagulability - splenomegaly - diffuse hemorrhage - local necrotizing or hemorrhagic lesions at site of entry - cattle: peracute - sheep: acute - swine: resistant; they can limit the disease to the throat or intestine |
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a meaty spleen that does not ooze blood is indicative of what pathogenic process?
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infiltrative disease of the spleen
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what are the two main rule-outs for an enlarged, infiltrated spleen?
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1. immune-related
2. neoplasia |
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what is the pathogenesis of non-neoplastic diseases that cause an enlarged, meaty spleen? What are two common diseases?
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pathogenesis: infiltration by immune cells, usually by macrophages related to a hemolytic disease
1. autoimmune hemolytic anemia - dogs 2. parasitic anemias such as anaplasmosis in cattle |
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how does an infiltrative neoplastic spleen present grossly?
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enlarged, diffuse (usually hematopoietic or "round cells"), pale, soft, and fragile
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what is the pathogenesis of scattered focal lesions throughout the spleen? what are three common etiologies?
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pathogenesis: a blood-borne disease targeting the white pulp. These create foci of necrosis in the spleen through lympholysis, endotoxins, or neoplasm.
1. Gram-gegative bacteria such as enteric salmonellosis 2. herpesviruses such as equine rhinopneumonitis 3. lymphomas |
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what part of the spleen is most likely to be affected with lymphoma first?
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the white pulp
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what is the most common solitary mass of the spleen and what species do they occur in? how do they appear and feel? why do they appear this way? malignant or benign?
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- nodular hyperplasia
- usually occurs in dogs - they range from blood-filled to pale - they are soft to reasonably firm - difference in appearance and feel is relative to number of blood or lymphoid elements in the nodules - they are benign and mimic neoplastic lesions |
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how does hemangiosarcoma present in the spleen?
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a solitary lump, which can undergo hemorrhage to form large hematomas that obscure the original neoplastic mass. They often rupture, which kills the animal.
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how do sarcomas and carcinomas that have metastasized to the spleen, commonly present?
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- sarcomas are usually deep
- carcinomas are usually surface plaques (e.g. from the pancreas or ovary) and are throughout the abdomen |
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how does lymphoma usually present in the spleen?
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a fleshy, pale, solitary mass
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what is the most common neoplasm?
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lymphoma
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abnormal medullary and/or extramedullary proliferation of one or more bone marrow cell lines
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myeloproliferative disease
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why is the incidence of myeloproliferative disease higher in cats than in other species?
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because of feline leukemia virus
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what are the two pathogenic pathways of erythrocyte destruction? clinical signs? etiology?
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1. intravascular (extracellular) - from a toxin; the RBC lyses, resulting in hemogloninemia, hemoglobinurea, anemia, and ultimately, kidney damage. Caused by toxins such as red maple in horses, leptospirosis, Clostridia.
2. extravascular (intracellular) - macrophages phagocytose the RBCs with surface abnormalities; hyperbilirubinemia and a large, meaty spleen. Etiology: hemangiosarcoma, other defective erythrocyte conditions, autoimmune hemolytic anemia. |
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list the four centers of hematopoiesis in order of activity with increasing severity of anemia?
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1. flat bones (normal)
2. long bones 3. spleen 4. liver |
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why would an ox present with widespread hemorrhage, thrombocytopenia, and increased capillary fragility?
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anthrax or bracken fern toxicosis
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what are the clinical signs for feline panleukopenia viral infection?
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(a parvovirus)
- symptoms mimicking radiation poisoning - attacks rapidly growing cells - lymphoid, bone marrow, and intestinal epithelium affected (diarrhea) - at the end-stages of the disease, thymic atrophy |
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why are hemolymphatic cells a good target for parvoviruses and radiation?
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because they are rapidly dividing
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anemia caused by replacement of bone marrow by tissues other than hematopoietic tissues
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myelophthisic anemia
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what are three main causes of myelophthisic anemia?
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(bone marrow replaced by non-hematopoietic tissue)
1. lymphoma 2. osteodystrophy fibrosa (fibrous degeneration of bone & formation of cystic cavities) 3. osteopetrosis (abnormal thickening of bone) |
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comment on the general relationship between a morphologic lesion of an endocrine gland and its physiologic state (e.g. amount of hormone secreted)
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there is not a correlation
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how can hyperplasia of an endocrine gland be distinguished from benign neoplasia histologically?
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neoplasia will compress the surrounding tissue whereas hyperplasia will not
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what is a major cause for pseudohyperparathyriodism in the dog?
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lymphosarcoma or adenocarcinoma of the anal sac gland
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what are three main pathogenic mechanisms for endocrine tissue hypofunction?
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1. autoimmune destruction
2. space occupying lesion (e.g. cyst or abscess) causing pressure-related destruction of healthy tissue 3. congenital lack of tissue |
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what are the embryologic origins of the pituitary?
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adenohypophysis: Rathke's pouch
neurohypophysis: brain |
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an autosomal recessive disorder in the dog resulting in the anterior pituitary being only a fluid-filled cyst
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juvenile panhypopituitarism
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a dog that is small in stature, has a juvenile appearance, small stature, and is losing hair probably has what? what is its etiology and pathogenesis?
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- juvenile panhypopituitarism
- etiology: a congenital defect that results in no oropharyngeal epithelium (Rathke's pouch) being formed - a fluid filled cyst instead of an anterior pituitary |
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how does pituitary pathology relate to dwarfism?
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sometimes it does when there is a pituitary lesion, but more often than not, dwarfism is not accompanied by a pituitary lesion
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what is the most common pituitary problem?
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pituitary adenoma
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in general, in what two ways can pituitary adenomas cause disease?
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1. space occupying effects
2. hyperfunction |
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what are two diseases caused by pituitary acidophil adenomas?
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1. acromegaly
2. diabetes insipidus (cats) |
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what clinical signs are associated with nonsecreting pituitary chromophobe adenomas? In which species do these commonly appear?
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- PU/PD
- cachexia - cats, dogs, parakeets |
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what are five clinical signs of pituitary adenomas in the horse?
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1. PU/PD
2. polyphagia 3. hyperhidrosis 4. hirsutism 5. intermittent hyperpyrexia |
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what are the three cell types of the adenohypophysis and what hormones do they produce?
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1. acidophils: somatotropin, prolactin
2. chromophobes: ACTH, endorphin precursors 3. basophils: TSH, FSH, LH |
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why would a pituitary adenoma cause PU/PD?
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it disrupts the secretion of ADH (diabetes insipidus)
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why would a pituitary adenoma cause blindness?
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compression of the optic chiasm
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why would a pituitary adenoma cause inappetance and chachexia?
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compression of the hypothalamus
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the parathyroid is stimulated to secrete in response to concentration of what two solutes in the blood?
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Ca and Mg
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generally, where are cysts most likely to occur?
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in embryologically complicated areas
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in general, what is hyperparathyroidism from a clinical pathology perspective?
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hypercalcemia
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what effect would the supplementation of calcium to have on the parathyroid glands?
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it will cause them to regress
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following the removal of a functional primary parathyroid adenoma, what happens to the physiologic state of the animal? why does this happen?
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hypocalcemia will result because the functional adenoma was causing so much calcium intake that the other parathyroid glands regressed.
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how does kidney failure lead to secondary hyperparathyroidism?
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- inadequate conversion production of 1,25-dihydroxycholecalciferol
- increased hydroxyappetite deposition into bone due to high phosphate levels |
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how can diet lead to secondary hyperparathyroidism?
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- hypovitaminosis D
- reverse Ca:P ratio |
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name three degenerative lesions of the thyroid gland and their ability to disrupt function
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1. copora amylacea (mineralized concretions) - rarely disrupt function
2. lipofuscin - incidental 3. amyloid - can cause dysfunction, but amyloid in the thyroid is rare |
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why are endocrine organs generally resilient to degenerative lesions?
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because they have a great deal of redundancy built into them, do they can have degenerative disease and still maintain function
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what are three causes of hypothyroidism?
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1. pituitary lesion (i.e. no TSH secretion)
2. idiopathic atrophy (most common) 3. lymphocytic thyroiditis |
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enlargement of the thyroid
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goiter
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goiter is usually what type of lesion?
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hyperplasia
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what is the pathological process of producing a colloid goiter?
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- thyroid is incapable of producing enough hormone (e.g. iodine deficiency)
- hyperplasia --> solid/diffuse goiter - enough hormone is now produced --> compensation - hyperplasia regresses, but size stays the same. colloid replaces the space that the hyperplasia took up --> colloid goiter |
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what are three causes of thyroid hyperplasia?
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1. Brassica toxicosis (kale, broccoli, etc.)
2. low dietary iodide 3. high dietary iodide (inhibits thyroid enzymes) |
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what animals commonly have congenital goiter?
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Goats, especially Boer goats
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what is the most common thyroid lesion in the cat? benign or malignant?
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multinodular hyperplasia, benign, but can cause hyperthyroidism
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what species have inherited dysmorphogenetic goiters? what causes them?
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- cattle, sheep, goats
- they are secondary to inborn errors in metabolism - these occur rarely |
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what are the three types of benign thyroid neoplasms?
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1. trabecular
2. oxyphilic 3. papillary |
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in dogs, why does carcinoma of the thyroid usually metastatize to the lungs?
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because the lymphatic drainage of the thyroid is directly to the lung without an intervening lymph node
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which species is at most risk for malignant thyroid carcinoma?
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dogs
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a dog presents with a palpable thyroid, but no signs of thyroid dysfunction. what is high on your rule-out list?
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malignant thyroid carcinoma
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why can prolonged, excessive calcium intake cause neoplasia of the thyroid? what species are at risk?
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- because the C-cells (parafollicular cells), which secrete calcitonin, can hypertrophy and then become neoplastic
- dairy bulls on alfalfa, horses |
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what are the zonas of the adrenal cortex? what hormones do they produce? which are pituitary-dependent?
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(outer to inner)
1. zona glomerulosa - corticosteroids (not pituitary dependent) 2. zona fasciculata - glucocorticoids (pituitary dependent) 3. zona reticularis - sex steroids, glucocorticoids (pituitary dependent) |
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in what species are accessory adrenal cortices common? where are they usually located? why are they located there?
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- cats and horses
- located near the gonads - they arise near each other embryologically (this is intuitive since they are both steroid-producing glands) |
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what usually occurs with the congenital absence of adrenal glands?
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death
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if a cat or horse has ectopic adrenal cortex, what problems are usually present? why?
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usually no problems because the adrenal glands already have built-in redundancy
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what is the most common pathogenesis of adrenal cortical hypoplasia?
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pituitary lesions
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which part of the adrenal cortex is most likely to maintain function secondary to a pituitary lesion? why?
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- zona glomerulosa
- not as dependent on pituitary function as the other zonas |
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what are the two most common senile changes to the adrenal cortex and the animals that they affect?
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1. mineralization - old cats and old dogs
2. capsular sclerosis - old bovines |
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what is adrenal cortical capsular sclerosis, in which species is it common, and why does it happen?
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- hardening of the adrenal cortical capsule caused by fibrosis and contraction of the adrenal gland
- happens in old cows (and bulls) - commonly in old cows with follicular cysts because estrogen favors the development of collagen |
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why are we not particularly worried about adrenal failure caused by amyloid deposition?
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because in these cases, amyloid is probably causing worse problems in other places
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what is the most common cause of adrenal cortical hemorrhage?
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- stressful or painful incidents
- routine and rarely causes problems |
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what are the two most common causes of inflammatory adrenal cortical lesions and what is the animal's prognosis for each type?
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1. herpesviruses in fetuses or neonates - poor prognosis
2. aberrant parasite migration - good prognosis (note that both of these are rare) |
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what are the three most common causes of adrenal cortical atrophy?
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1. idiopathic (most common)
2. secondary to inflammation 3. pituitary lesion (i.e. reduced ACTH secretion) |
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what are the two most common types of adrenal cortical hyperplasia and the dysfunction they cause?
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1. nodular - incidental
2. diffuse - usually due to increased ACTH, which will cause a Cushing's-like disease |
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what is the most common type of adrenal medullary lesion?
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neoplasia
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what are the three most common adrenal medullary neoplasms?
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1. pheochromocytoma (most common)
2. neuroblastoma (rare) 3. ganglioneuroma (rare) |
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what are clinical signs and pathological presentations of malignant pheochromocytoma?
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- repeated collapsing due to uncontrolled release of vasoactive catecholamines
- tumor infiltrates into vena cava and aorta |
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what are the two major chemoreceptors? what is a neoplasm of a chemoreceptor called? where are these neoplasms usually found? how do they present grossly?
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- carotid body and aortic body
- called chemodectomas (usually benign) - usually found at the base of the heart - can present as an enlarged heart base |
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what is the most common disease secondary to a pancreatic islet lesion?
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diabetes mellitus
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how can pancreatitis cause diabetes?
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through non-specific loss of islet tissue (self-digestion)
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how do pancreatic islet lesions differ between the cat and dog?
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dog: non-specific loss of function, usually through exocrine pancreatitis
cat: usually specific either through inflammation of the islets or amyloidosis of the islets |
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what are the two most common neoplasms of the endocrine pancreas and associated clinical signs?
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- insulinoma --> episodic hypoglycemia --> collapse
- gastrinoma --> gastrin secretion --> hyperactive gastric lining --> pyloric and duodenal ulcers |
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what species are commonly susceptible to endocrine pancreatic neoplasms?
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dogs, cats, ferrets
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what is the first step in sexual differentiation in the embryo?
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gonadal differentiation
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which embryonic structures are associated with the male and female tubular reproductive structures?
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- male: mesonephric duct
- female: paramesonephric duct |
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how does the hY antigen affect gonadal differentiation in the embryo?
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- mammals: hY+ = male; hY- = female
- birds: hY+ = female; hY- = male |
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what determines which tubular tract will develop in the embryo?
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gonadal hormones. Androgens cause development of the mesonephric duct; Proteins in the testis (regressing factor) cause regression of the paramesonephric duct; In the absence of male hormones (females) the paramesonephric duct develops.
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how do androgens act on the brain of the fetus?
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they rearrange the hypothalamus to be acylic
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what is a true hermaphrodite?
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an animal with both ovarian and testicular gonadal tissue.
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ovarian and testicular tissues combined into the same gonad
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ovotestis
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why are animals born as true hermaphrodites?
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because some hY antigen is present
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in what species has true hermaphroditism been traced? Where does this genotype exist?
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dogs, X-linked
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an animal having the gonads of one sex but the tubular tract of the other
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pseudohermaphrodite
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what is the most common type of pseudohermaphrodite? what "parts" do they have?
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male pseudohermaphrodite. Male testes, female genitalia.
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in what species are male pseudohermaphrotiditism important? what is a common clinical disease associated with this defect?
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- swine: uterus becomes distended --> hydrometra --> pyometra --> peritonitis --> death
- dogs (cocker spaniels, miniature schnauzers): cryptorchid --> cystic endometrial hyperplasia --> pyometra - goats: hypospadia (failure of penis to close around the urethra); cryptorchid; genetically female; genitalia range the whole spectrum |
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what is hypospadia?
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failure of penis to close around urethra
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the failure of the penis to close around the urethra (genetic defect)
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hypospadia
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what breed of goats are most susceptible to being born as male pseudohermaphrodites?
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homozygous polled Swiss breed goats
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what are consequences of testiscular feminization in the embryo?
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somatic cells are resistant to androgens, so no male or female tubular tract
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what is the only well-documented female pseudohermaphrotidism in animals?
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- adrenogenital syndrome
- normal ovaries - abnormal enzymes in adrenal system leads to development of male genitalia - ovaries do not descend into scrotum |
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what are the two embryologic steps required to form a freemartin?
|
1. fusion of placentas
2. exchange of cells and hormones |
|
|
what are the morphologic changes in the freemartin?
|
- overall: suppression of female characteristics and enhancement of male characteristics
- Normal vestibule - enlarged clitoris - small or absent vagina - uterus with horns but no body or cervix - small gonads - seminal vesicles - prominent rete ovarii |
|
|
why do freemartins have a normal vestibule and urethra, but deformities in the vagina and other parts of the repro system?
|
because the vestibule and urethra have ectodermal origins and are not sensitive to the gonadal hormones during embryological development
|
|
|
how does increased gonadal size affect reproduction?
|
- earlier puberty
- higher fecundity - longer reproductive life |
|
|
what does a hypoplastic ovary look like?
|
small, "squashed", wrinkled surface
|
|
|
what is the most common cause of ovarian hypoplasia?
|
germ cell deficiency
|
|
|
why would a spayed bitch still exhibit signs of heat?
|
she had accessory ovaries that were not completely removed
|
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|
small tags of fibrous tissue or fine adhesions between the ovary and bursa
- name - pathogeneses |
- ovarian tags
- clotting of fluid post-ovulation - inflammation from bacteria that have ascended up the uterine tube |
|
|
in the mare and cat, small yellow masses in and around the ovary
|
ectopic adrenal cortical tissue
|
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|
inflammation of the ovary
|
oophoritis
|
|
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what is an important cause of oophoritis in cows?
|
tuberculosis
|
|
|
why is oophoritis more common in ruminants than other species?
|
because the uterotubal junction is not a tight barrier in ruminants, as opposed to other species
|
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|
spherical, clear, fluid-filled cysts around the ovary
- name - etiology - affect on fertility |
- parovarian cysts
- remnants of the mesonephric ducts - usually no consequence to fertility - large cysts in bitches and queens can cause pressure necrosis of the ovary |
|
|
where are parovarian cysts usually located? how are they named if located elsewhere?
|
- usually at the hilus and in the mesovarium
- if at the cranial pole, they are called epoophoron - if at the caudal pole, they are called paroophoron |
|
|
in which species are cysts of the rete ovarii most common? how do they cause disease?
|
- dogs, cats, guinea pigs, and mice
- pressure necrosis of the ovary - stretches ovarian cortex and interrupts normal intraovarian communication |
|
|
what is a germinal inclusion cyst? when do they impair function?
|
- following ovulation, a portion of the mesovarium gets trapped in the ovarian stroma. The mesovarium is secretory, so a cyst develops
- they can cause infertility in the mare because she only ovulates through the ovulation fossa |
|
|
what is a cyst that commonly occurs in the bitch that resembles germinal inclusion cysts? how are they different?
|
- germinal epithelium sends projections down into the subsurface of the ovary.
- in contrast to germinal inclusion cysts, these tend to be larger and grow in response to estrogen |
|
|
what is the most common pathogeneis of a cystic ovarian follicle? what species are these most commonly problematic?
|
- failure of adequate LH release from the pituitary prevents ovulation
- more common in dairy cattle; "COD" |
|
|
what is the pathogenesis of a luteinized cyst?
|
- failure of adequate release of LH prevents ovulation and a cystic ovarian follicle develops
- with LH secretion, this becomes luteinized |
|
|
what is the difference between a luteinized cyst and a cystic corpus luteum?
|
- a luteinized cyst did not ovulate and has no papilla
- a cystic corpus luteum did ovulate, and filled with fluid or tissue, and has a papilla |
|
|
what are two types of cysts, especially occurring in cattle, that occur from oophoritis? what is their morphology?
|
1. tubo-ovarian cyst - following dense adhesions caused by oophoritis, tubular-shaped cysts involving only the uterine tube
2. cystic ovarian bursae - due to adhesions caused by oophoritis, large, irregular cysts that envelop the entire ovary - both can be up to a foot in diameter |
|
|
if a mare has a single, large ovarian cyst, what most likely is it? Pathogenesis?
|
- remnant of a granulosa cell tumor
- the neoplasm stimulates fibrous production of a wall around the tumor as a result of estrogen stimulation. The tumor dies and becomes a liquefactive necrotic cyst |
|
|
in ovarian neoplasms, which type of tissue is most commonly neoplastic? What are the three basic types of neoplasia in these cases?
|
- stroma
1. Granulosa cell tumor 2. Thecoma 3. Luteoma |
|
|
what do granulosa cell tumors of the ovary usually look like?
|
firm, white, and cystic
|
|
|
what do thecomas and luteomas of the ovary usually look like?
|
solid (not fluid filled), firm to soft, white to gold-orange
|
|
|
which type of ovarian stromal cell tumor is most likely not to be a mixed tumor and why?
|
granulosa cell tumor, because it forms a cyst
|
|
|
what is the morphology of benign versus malignant thecomas and luteomas?
|
- benign: smooth surface
- malignant: rougher, shaggy surface and metastasize throughout the peritoneum |
|
|
why are luteomas prone to metastasis?
|
because they have a rich blood supply
|
|
|
what is the most common type of ovarian neoplasm in the mare? what is their morphology? what behavioral changes to mare are common?
|
- granulosa cell tumor
- unilateral, solid or cystic - cause virilism (masculine behavior) or nymphomania - these tumors produce testosterone |
|
|
how can malignant ovarian papillary adenocarcinomas lead to ascites?
|
- they are shaggy and the piece of shag breaks off into the peritoneum
- these can plug up the diaphragmatic lymphatics - ascites is the result - note, these are not as invasive as normal metastatic tumors |
|
|
what are the four common types of neoplasms of germ cells?
|
1. dysgerminomas
2. teratomas 3. "epithelial" papillary adenomas 4. "epithelial" cystadenomas |
|
|
what is a common pathogenesis of hydrosalpinx?
|
inflammation --> fibrous deposition --> clogged uterine tube --> hydrosaplinx
|
|
|
uterine tube cysts:
- embryologic origin - location, size, shape - impact on fertility |
- paramessonephric duct cysts are in the free edges of the fimbriae of the infundibulum, up to 1 cm (cow and mare), and round. they do not usually impact fertility
- mesonephric duct cysts: in or adjacent to the wall of the uterine tube and spherical. the do not usually impact fertility |
|
|
in what species is inflammation of the uterine tube most common. why?
|
cows, because the cervix in the cow is the main barrier to the environment and the uterotubal junctions are "looser." Infections of the uterus can ascend up the uterine tube. In other species, the opposite is the case.
|
|
|
what are three common possible end-stages of pyosalpinx?
|
1. return to normal of no adhesions develop
2. small cysts can be left 3. large cysts (or even the entire length of the tube is cystic), leading to hydrosalpinx and infertility |
|
|
in cysts of the uterine tube, which morphology of the cyst is most likely and least likely to cause infertility?
|
- tubular cysts cause infertility
- spherical cysts are less likely |
|
|
in which species are neoplasms of the uterine tube most common?
|
birds
|
|
|
what is the most common malformation of the uterus? in which species is this most common? how does this malformation present? how does it affect fertility?
|
- segmental aplasia.
- most common in cows. - a portion of one or both uterine horns is missing. - infertility if both horns are missing |
|
|
unilateral anterior segmental aplasia of the uterus where the aplastic horn is intact and cystic:
- what is it called? - why is this a problem? |
- uterus unicornis
- a CL in this malformed structure cannot be lysed |
|
|
why can post-partum involution of the uterus develop cysts? how do these affect fertility?
|
becuase it wrinkles and since the surface is serosal, small adhesions can become cystic. they are harmless.
|
|
|
what is the most common type of degenerative lesion of the uterus? what are some etiologies?
|
- endometrial cystic hyperplasia
- cow: due to estrogenic influences such as cystic follicles - sheep: subterranian clover in pasture (phytoestrogens) - unbred bitch: prolonged anestrus due to not being bred |
|
|
what is a common pathogenesis of pyometra in the unbred bitch
|
- unbred = longer anestrus under the influence of progesterone
- progesterone --> lower immune response and lower PMN efficiency - progesterone --> cystic endometrial hyperplasia --> hydrometra - hydrometra/mucometra --> pyometra |
|
|
why does endometrial cystic hyperplasia that is under the influence of estrogen, generally lead to infertility, but not pyometra?
|
- estrogen boosts the immune response
- hyperplasia --> hydrometra - no progesterone --> no endometrial growth --> pressure atrophy --> sterility |
|
|
in what species is estrogen-influenced endometrial cystic hyperplasia most common?
|
queen
|
|
|
what is another name for pseudopregnancy?
|
pseudocyesis
|
|
|
what is a very common degenerative condition of the uterus in mares that can result in sub-optimal fertility? why does this cause infertility?
|
fibrosis of the endometrium. the fibrosis causes the endometrial glands to occur in clusters instead of being diffuse
|
|
|
what is a good historical indication of a mare's ability to conceive?
|
her past reproductive performance
|
|
|
what is the significance of post-partum inflammatory cells in the uterus?
|
this is normal unless it is purulent
|
|
|
in the cow, when should the uterus return to its non-pregnant size? when should lochia be completely discharged?
|
- involuted by day 14
- lochia discharged by day 10 |
|
|
degraded bits of caruncle and placenta in the bovine uterus, post-partum
|
lochia
|
|
|
if the post-partum caruncles do not liquefy and pass out of the uterus before involution, what can happen?
|
pseudopregnancy: the presence of these materials in the uterus will prevent the cow from cycling
|
|
|
what are common etiologies of metritis/endometritis in the cow?
|
- post-partum or post-abortion disease
- pyometra - retained CL --> pyometra - Mycoplasma bovis |
|
|
what veneral disease of bovines can result in endometritis? Who is particularly susceptible?
|
- Mycoplasma bovis
- especially susceptible: virgin heifers that have not developed immunity to M. bovis |
|
|
when is the common time for mares to acquire endometritis? why does it occur? how can this impact fertility?
|
- post-breeding
- failure of implantation will cause inflammation - inflammation can cause fibrosis and be determental to fertility because the endometrial glands occur in clusters instead of being diffuse |
|
|
what is a common infectious etiology of endometritis in the bitch?
|
distemper
|
|
|
what two things commonly cause granulomatous metritis? what would be seen histologically
|
1. tuberculosis
2. oil-based medications that can't be eliminated by the uterus - histology: focal lesions of giant cells and macrophages |
|
|
in the cow, how does the location of a uterine abscess relate to its etiology?
|
- dorsal: trauma due to AI
- ventral: trauma due to calving |
|
|
what is the common pathogenesis of ectopic fetuses in litter-bearing species during necropsy?
|
- torsion of the uterine horn
- tear of the uterine horn and fetus deposits in peritoneal space - uterus twists back and heals |
|
|
why can an endometrial fibroadeomatous polyp cause infertility? death?
|
- infertility: they are a space-occupying lesion that prevents pregnancy
- death: they can be the center of uterine torsion --> ischemia --> necrosis --> shock --> death |
|
|
what are four hyperplastic/neoplastic lesions of the uterine epithelium?
|
1. fibroadenomatous polyps
2. leiomyomas 3. leiomyosarcomas 4. lymphosarcomas |
|
|
benign, smooth muscle neoplasms of the uterus
|
leiomyomas
|
|
|
malignant neoplasm of the uterine myometrium
|
leiomyosarcoma
|
|
|
what term is used to describe the dense, fibrous carconomas of the uterus?
|
schirrous
|
|
|
firm, dimpled, fibrous lesions of the uterus are likely to be what?
|
uterine carcinomas - highly metastatic
|
|
|
in what species are shirrous uterine carcinomas most common?
|
cows and rabbits
|
|
|
what abnormalities of the cervix commonly occur if the paramesonephric ducts fail to completely fuse?
|
- dorso-ventral band
- partially duplicated cervix - two cervices and two uteri, each with only one horn |
|
|
condition of having two cerivices, uteri, and one horn per uterus
|
uterus didelphys
|
|
|
what is the most common cervical abnormality in the cow?
|
duplication of the caudal rings. The dorso-ventral band can sometimes be in the vagina
|
|
|
what is the common end-stage of cervical hypoplasia in the cow?
|
chronic endometritis --> infertility
|
|
|
what is the common end stage of a severely deformed cervix in the cow?
|
- mucometra/hydrometra --> infertility because the uterus cannot discharge properly
|
|
|
how does the cervix of the zebu differ from the humpless cow?
|
it is naturally larger and can be confused as a malformed cervix
|
|
|
how does prolapse of the cervical rings in cows lead to infertility?
|
they become edematous. then they become fibrous, which causes the cervix to contract, restricting its opening
|
|
|
what is the most common etiology of cysts in the vaginal wall?
|
persistent mesonephric ducts. Not a problem
|
|
|
why can the vagina protrude through the lips of the vulva in a bitch that is in estrus?
|
it is caused be edema of the mucosa, which becomes organized into fibrous connective tissue over several cycles. they can resemble polyps, which themselves become especially edematous during estrus.
|
|
|
what is "granular venereal disease"
|
exudation of neutrophils and hyperplastic lymphoid follicles in the vagina due to a variety of bacterial infections
|
|
|
in the bitch, when is vaginits most common?
|
puppies before their first estrus
|
|
|
a tear resulting from trauma that goes through the vagina and rectum
|
rectovaginal fistula
|
|
|
a venereal disease of horses that cause ulcerated foci on the vulva and skin. What causes this?
|
Coital exanthema - caused by a herpesvirus
|
|
|
why are squamous cell carcinomas of the vulva so dangerous?
|
because the tumor tissue can slough off and be transmitted sexually, causing malignant squamous cell carcinoma in other animals
|
|
|
what are some common etiologies of vulvitis?
|
- ureaplasmas in the cow
- infectious pustular vulvovaginitis virus in the cow - bacteria |
|
|
what is the most common cause of testicular hypoplasia?
|
germ cell deficiency
|
|
|
what is the best way to eliminate testicular hypoplasia in a line?
|
select for large scrotal circumference
|
|
|
in which species are cryptorchidisms most common?
|
horse, pig, dog
|
|
|
what is a common disease caused by a cryptorchid testis that is not removed?
|
Sertoli tumor
|
|
|
why should you be careful when removing a cryptorchid testis in the horse?
|
because the testis is very small and not well adhered to the epididymis. you might accidentally leave the testis in the horse.
|
|
|
why is the testis in the equine fetus so large?
|
interstitial cell hypertrophy due to high estrogen production (sustains pregnancy)
|
|
|
what is a common comorbidity of monorchidism?
|
missing kidney on the opposite side
|
|
|
comment on the practical impact of and reversibility of testicular degeneration
|
- results in reduced spermatogenesis (lower sperm count)
- some conditions are reversible and others are not |
|
|
what two factors determine the prognosis of a testicular degenerative disease being reversible?
|
1. length (time)
2. severity - good prognosis: short and mild - poor: long or short & severe |
|
|
if you cut the capsule of a normal testis, what should occur?
|
the parenchyma should bulge out of the surface
|
|
|
what lesions are common in testicular degneration?
|
- cells replaced with fluid
- collapse, resulting in a soft testis - immature germ cells in the lumen and ejaculate - multinucleate spermatid giant cells in the lumen and ejaculate |
|
|
what are two common causes of orchitis?
|
- Brucella
- Strongylus edentatus |
|
|
what is the common end-result of sperm stasis?
|
blockage as a result of granuloma formation and subsequent mineral concretions
|
|
|
what is the most common etiology of an infarcted testis? in which species are these most common?
|
torsion. most common in horses and dogs
|
|
|
what are the five common testicular neoplasias?
- color - shape - texture - species affected |
|
|
|
in what animal is lymphosarcoma of the testis most common?
|
rams
|
|
|
what is the color, shape, and texture of a Leydig cell tumor?
|
gold/tan, round, soft
|
|
|
what is the color, shape, and texture of a Sertoli cell tumor?
|
white, lobulated, very firm
|
|
|
what is the color, shape, and texture of a Semenoma?
|
gray, round, soft
|
|
|
what is the most common malformation of the epididymis? what is the pathological result?
|
failure of the efferent ductules to connect to the epididymal duct. results in sperm stasis --> granuloma --> mineral concretions
|
|
|
why does sperm stasis cause granulomatous inflammation?
|
because they contain mycolic acid, the same substance found in M. tuberculosis
|
|
|
why is mild inflammation in the epididymis or testis bad?
|
because the tissues are exquisitely sensitive to damage
|
|
|
what is the usual culprit for severe epididymitis and describe the lesions?
|
Brucella infections will cause abscess formation in the epididymis
|
|
|
compare the etiology of epididmyal defects depending on location along the epididymis.
|
head - usually a congenital malformation
tail - usually an acquired malformation, e.g. an ascending infection |
|
|
outgrowth of ductal epithelium of the epididymis into the surrounding muscle
|
adenomyosis
|
|
|
what is adenomyosis of the epididymis? what are two common causes? common species?
|
outgrowth of the ductal epithelium into the surrounding muscle.
1. too much steroid synthesis (feminizing Sertoli cell tumors) 2. chronic inflammation - common in rams; bulls fed a hormone drug |
|
|
what is a very important aspect of the vaginal tunic of the testes and spermatic cord?
|
it is continuous with the peritoneum; castration can lead to peritonitis
|
|
|
what is a common remnant of the paramesonephric duct in the otherwise normal male?
|
uterus masculinis
|
|
|
what is the embryologic origin of the seminal vesicles?
|
mesonephric duct
|
|
|
in the male, what is usually the first part of the reproductive tract to become affected with inflammatory disease? how does the inflammation progress? when is it usually noticed clinically?
|
starts in seminal vesicle --> ductus deferens --> epididymis is where it is commonly seen
|
|
|
what is a useful early method to detect some kinds of male reproductive tract inflammatory diseases?
|
neutrophils in the semen
|
|
|
what is a common cause of vesculitis in bulls that can damage the sperm viability?
|
Mycoplasma bovigenitalium
|
|
|
how can a "natural service" bull infected with Mycoplasma decrease fertility wihtout having a low sperm count?
|
by infecting the female, which can cause infertility in her or abortion
|
|
|
which species has the most prostate problems?
|
dog
|
|
|
how can you differentiate acute from chronic prostatitis in the dog?
|
- acute: lesion is fluctuant, hot, and painful
- chronic: abscess presents as a soft spot in the otherwise firm prostate |
|
|
what are two common causes of a symmetrically enlarged prostate? pathogenesis? treatment?
|
1. hyperplasia
2. squamous metaplasia caused by estrogenized testes castrate |
|
|
what are three causes of an unsymmetrically enlarged prostate in the dog?
|
1. prostatitis
2. "cysts" 3. neoplasia |
|
|
what are the two types of malignant neoplasias of the dog prostate? what is the degree of severity of malignancy? how can they be distinguished from hyperplasia?
|
- carcinoma and adenocarcinoma
- extremely malignant - epithelium is stratified; epithelial cells are pleomorphic and have poor relationship to the basement membrane |
|
|
what is the most common cause of pathologic change in the bulbourethral glands? why is this important?
|
- squamous metaplasia in rams or wethers that feed on estrogenic subterranian clover pastures
- these lesions can be confused with tapeworm cysts and cause carcass condemnation |
|
|
in which species is a double-penis most common?
|
bulls
|
|
|
inflammation of the penis
|
balanitis
|
|
|
what is the most common cause of non-specific balanitis? Common species?
|
older animals have wrinkly penises (keratinized crypts) that extrude more often, and can become infected and exude neutrophils. Dogs and zebu bulls.
|
|
|
what are two causes of specific balanitis of horses?
|
1. coital exanthema caused by a herpesvirus
2. Habronema larvae |
|
|
what are three common neoplasms of the penis? species? etiology?
|
1. papilloma - usually viral and regress
2. squamous cell carcinoma - carcinogenic effects of smegma in horses 3. transmissible venereal tumor in dogs |
|
|
why is infection of the placenta very bad?
|
it is an immunologically privileged site
|
|
|
name the extra-embryonic membranes from outside to inside
|
1. chorion
2. allantois 3. amnion |
|
|
large cysts on the umbilicus of the foal are probably what?
|
yolk sac cysts
|
|
|
if you see a red, velvety texture on a bovine placenta, what is the likely cause? why is this important
|
it is adventitious placentation, usually caused by damaged caruncles. This is indicative of uterine damage.
|
|
|
comment on the prevalence and gross appearance of placentits caused by:
- protozoa - fungi - viruses - bacteria |
- protozoa: rare, multiple small foci
- fungi: common, gross lesions - viruses: don't usually occur - bacteria: common, gross lesions |
|
|
what how does the appearance of a normal placenta compare with one with severe placentitis?
|
- normal: shiny, translucent
- placentitis: leathery, dull-brown |
|
|
what is the most common reason that a fetus dies from placentitis?
|
vasiculitis of the placental blood vessels, which impair oxygen and nutrient flow
|
|
|
dull, white calcified structures on the chorion or keratinized plaques on the amnion are indicative of what?
|
nothing. this is normal, especially in pigs and ruminants
|
|
|
amorphous, rubbery masses that develop in the allantoic or amniotic cavity of horses and cattle
|
hippomanes
|
