Lecture 12: Canine Andrology & Male Infertility (Kelleman) Flashcards
accessory sex glands in dog
prostate only
stud dog BSE includes
Hx
Brucella status
semen collection & evaluation
general physical, scrotal, and prostatic exams (check for cryptorchid, retained testes)
neoplasia common to retained testes
seminoma, Sertoli cell tumor
3 semen fractions in canine
1 and 3: prostatic
2nd: sperm (cloudy white)
teasing
tease stud with in heat female or swabs from in heat female
frenulum normal or abnormal in stud dog?
abnormal (snip it)
normal motility**
> 70-80% motile or progressively motile
normal morphology**
> 80% normal
how many sperm should you count?
at least 100
parts of sperm
head neck middle piece principal piece (tail) end piece
use what stain to evaluate sperm
eosin nigrin
can use H&E to evaluate for red/white cells, epithelial cells, etc.
method of determining concentration of sperm
hemacytometer:
-dilute sperm 1:100, count # in central box for #millions/ml
total number of sperm =
volume x concentration
-depends on technique, presence of estrous teaser, weight/size of dog (testes)
avg. # sperm/lb. BW
10 million
semen with WBCs is normal or abn?
abn
scrotal exam
- do after collection
- epididymis should be caudal
- evaluate symmetry, size, texture, consistency, orientation, spermatic cords of testes
- scrotal skin issues? (dermatitis can affect temp.)
T/F: prostate should be palpable in intact dogs
T (caudal portion only). should have symmetry and non-painful
most common cause of apparent infertility
breeding at improper time
azoospermia**
ejaculation of seminal fluid that doesn’t contain sperm
oligospermia**
low total number of sperm
-not necessarily sterile
teratozoospermia**
decreased percentage of morphologically normal sperm (<70% normal) (correlated with asthenozoospermia)
asthenozoospermia**
progressive motility of less than 70% (correlated with teratozoospermia)
-may be first indication of infection
causes of testicular azoospermia
intersex animals
germinal cell aplasia (testicular tissue didn’t form correctly)
bilateral cryptorchidism
testicular trauma (causes insulation –> high temp)
autoimmune orchitis
testicular neoplasia
what are likely causes of male infertility if stud can breed naturally, has normal semen quality, and breeding is timed properly?
prostate dz
brucellosis
testicular neoplasia
genetic incompatibility
what are likely causes of male infertility if stud can’t breed naturally?
behavioral
pain
prostate dz
penile abn.
what are causes of male infertility if stud can breed naturally, but semen quality isn’t normal?
aspermia (libido, apprehension, pain, young/old)
azoospermia (abn. sex. develop, hypo T4, apprehension, cryptorchid, high fever, neoplasia, occlusion)
oligospermia (orchitis, prostatitis, pain, hypo T4, retrograde ejac., high fever)
terato-zoospermia (orchitis, prostatitis, brucellosis, neoplasia, hypo T4, high fever)
asthenozoospermia (same as terato. + ciliary dyskinesia)
(see slide 26)
methods of diagnosing azoospermia
testicular palpation karyotype culture of seminal fluid brucella testing testicular ultrasound testicular aspiration, biopsy if final stge -risk of infection, hemorrhage
alkaline phosphatase
- measured when azoospermia suspected
- present in high conc. in semen (<5,000 IU/L indicates incomplete ejaculation from bilateral obstruction of ejaculatory ducts)
- originates from tail of epididymis
zeuterin
- chemical sterilant injected into testis to cause azoospermia
- destroys testicular tissue
- used when sx too expensive
causes of oligospermia
idiopathic (11%) seasonal (heat/cold) testicular neoplasia prostatic dz orchitis/brucella hypothyroidism fever drugs (glucocorticoids, estrogens, ketoconazole, chemo)
abnormalities correlated with teratozoospermia
midpiece attachment, ultrastructure
microcephalic sperm
proximal droplets
acquired causes of teratozoospermia
testicular tumors orchitis prostatitis high fever obesity sexual abstinence hypothyroid
causes of asthenozoospermia
testicular tumors orchitis prostatitis high fever obesity sexual abstinence hypothyroid primary ciliry dyskinesia latex exposure water-soluble lubricants
prostate cancer effects intact or castrated dog more?
castrated
chars. of canine prostate
only accessory gland* smooth, bilobed encircles urethra androgen-dependent produces 1st and 3rd fractions
benign prostatic hypertrophy chars.
- androgen dependent
- age-related (>5yrs)
- CS: asymptomatic or incontinence, tenesmus, “ribbon-like” stool, hematuria
- symmetrical enlargement
- nonpainful on palp.
tx of benign prostatic hypertrophy (BPH)
- castration (50% reduction in 3 wks)
- anti-GnRH vaccine (no longer available)
- finasteride (lowers testosterone that dog sees)
finasteride
- 5a reductase inhibitor
- lowers testosterone that dog sees
- decreases semen volume
- no effect on libido, semen quality
prostatitis
- inflammation +/- infection of prostate
- occurs 2ary to BPH
- acute or chronic
- ascending or hematogenous
- common in older dogs
- abscessation
- prostatic cysts
signs of ACUTE prostatitis
- painful on palp.
- clinically ill (v, anorexia, fever, abd. pain)
- dec. libido
- pain on ejaculation
- hemospermia
signs of CHRONIC prostatitis
- typically subclinical
- may present for recurrent UTI
- urethral discharge
- poor semen quality, hemospermia
- infertility
- nonpain palp.
- symmetric or asymmetric on palp.
tx of prostatitis
castration
acute: tx CS (IV fluids, abx)
chronic: long-term oral abx (fluroquinolones, sulfa, or chloramphenicol)
prostatic neoplasia
- common in CASTRATED older dogs
- adenocarcinoma
- asymmetrical firm enlargement
- calcification on US
- lung, bone mets
- grave prognosis
Brucella canis chars.
- gram negative aerobic coccobacillus
- limited do dogs and wild canines
- intracellular infection
- ZOONOTIC
- difficult to clear
- acquired through mm (oronasal contact with vaginal discharge/aborted materials, seminal fluid, urine, fomites)
dx of brucellosis
screen q 6mo. using RSAT test
- sensitive but not specific (false positives common**)
- neg. result is usually true negative**
- RSAT+ should be confirmed with Ag testing
Clicker Q: which of the following most likely from Brucella canis infection?
2yo male, peripheral lymphadenopathy with discospondylitis
what to do with animals positive for Canine Brucellosis
- reportable in some states
- isolate for testing
- sterilize
- euthanasia/depopulation (shelters)
shedding of canine brucellosis more/less likely in neutered animals?
less
absence of penile spines in tom cat means:
tom cat doesn’t have adequate testosterone
-most common cause = castration
penile spines regress how soon after castration?
5-6wks
reasons for tom infertility***
- penile hair rings
- mate preference
- karyotype or intersex issues (male calico or toroise shell)***
- cryptorchidism
- nutritional testicular degeneration (i.e. riboflavin, EFA linoleate, Vit. A deficiency)
- orchitis (bacterial from trauma, bites)
- FIP (peritonitis extending to tunic surrounding testes)
methods of semen collection in toms
emission with sedation (using tom cat catheter)
electroejaculation
