Therio - Stallion Repro Dz

drraythe's version from 2017-09-10 04:07

Intro + Impotentia coeundi

Question Answer
Basic reasons there might be Impotentia coeundi? (List for reading)Pain (musculoskeletal or back pain), Penile trauma, Neoplasia, Habronemiasis, Coital exanthema (EHV-3)
Basic reasons there might be Impotentia generandi? (List for reading)Cryptorchidism, Inguinal/scrotal herniation, Torsion of the spermatic cord, Orchitis, Scrotal trauma, Testicular degeneration, Testicular atrophy, Blocked ampulla, Tear in the pelvic urethra
What are the 2 major viral venereal Dzs?Coital exanthema (EHV-3)
Equine Viral Arteritis (EVA)
What are the 3 major bacterial venereal Dzs?Contagious Equine Metritis (CEM- Taylorella equigenitalis)
What is the main protozoal venereal dz of horses?Dourine (Trypanosoma equiperdum)
What’s Impotentia coeundi?Problem w/ the act of sex, not generating the things capable of fertilization
What are some common czs of penile trauma?Cuts after breeding, Kick from mare, Penetrating object from bedding, Others: stallion ring, castration, etc…
How do you treat cases of penile trauma?Stall rest, Elevate → Replace the penis in the sheath (if possible) & put in retention stitches (or apply sling/belly wrap to suspend penis), Lubricate, Cold water hydrotherapy 2-4x/day, Diuretics, NSAIDs, corticosteroids, AB’s, Sexual rest
What are the chronic effects of penile trauma?May get scar tissue formation resulting in phimosis or paraphimosis
What is Paraphimosis?Inability of the horse to retract the protruded penis into the preputial cavity (trauma, exhaustion...)
What is Phimosis?Inability of the horse to protrude its penis from the preputial orifice or preputial ring
What is Priapism?Persistent erection w/o sexual stimulation (most often following phenothiazines) can lead to paraphimosis & paralysis. AVOID ACEPROMAZINE IN STALLIONS
Priapism is usually czd by what & results in what problems?Usually cz by phenothiazines (DONT GIVE STALLIONS ACEPROMAZINE) & can lead to paraphimosis & paralysis
How common are penile neoplasias?Penile neoplasia form up to 10% of equine tumors
4 most common types of neoplasias?Squamous Cell Carcinoma, Sarcoid, Melanoma (greys), Papilloma (benign on the genitalia of young horses, disappears w/ acquired immunity against the virus)
What does SSC look like? What are the DDx?DDx: Habronema, Sarcoid
Habronemiasis → aka? What czs this? DDx?Aka summer sores, czd by migration of Habronema larvae. DDx SCC
How do you Dx & Tx habronemiasis?DDx: Biopsy
Tx: Fly prevention/ Sexual rest/ Systemic & topical anthelmintic (ivermectin etc)

Impotentia generandi

Question Answer
When do testicles usually descend in stallions?Testes normally in scrotum btwn 30 days before & 10 days after birth
How common is cryptorchidism, & is it usually uni or bilateral?Cryptorchidism is seen in 5-8% of foals & is most frequently unilateral
What is a rig?Cryptorchid stallion
How might you be able to Dx cryptorchidism w/ a rectal palpation?Find the inguinal ring & feel for the spermatic cord running through it
Cryptorchidism → hormone assay dx → Basal Testosterone levels of a NORMAL stallion?0.5 to 1ng/ml
Cryptorchidism → hormone assay dx → Basal Testosterone levels of a GELDING?0.05 to 0.1ng/ml
How do you do a hCG stimulation test to Dx a cryptorchid?(Remember that hCG has LH like effects) Take blood sample before hCG administration. Administer hCG 10,000 IU IV or IM (Chorulon®). Take blood samples at 30 min intervals for up to 3h after hCG administration (if only 1 sample then take at 3h after hCG). Normal & cryptorchid stallions should have a marked increase in testosterone in response to hCG
What other hormone can you measure aside from testosterone to try to determine if you have a cryptorchid?Antimüllerian Hormone (AMH) (cryptorchid will have high levels of this, even higher than stallion)
5 main DDx for a swollen scrotum?Inguinal hernia
Hydrocele (Pitting oedema – usually lack of exercise)
Torsion of the spermatic cord, Orchitis, Trauma
Is inguinal/scrotal herniation congenital or acquired?Could be either
CSs of inguinal/scrotal herniation?Colicky – especially if strangulated. Swollen scrotum. Pain on palpation of scrotum. May be able to reduce herniated intestines
DDx & Tx of inguinal/scrotal herniation?DDx: U/S
Tx: Sx
Torsion of the spermatic cord most commonly occurs in what type of testes?Common w/ retained cryptorchid testis but may occur intra-scrotal
Which degrees are common in torsion of the spermatic cord?Can be 180° or 360° torsion
What is the major problem czd by torsion of the spermatic cord?Ischemic damage
CSs of spermatic cord torsion?*180° torsion sometimes have no CSs!! Will see: COLIC!!!!, Swelling & pain of scrotum, NB!! check Orientation of the testis
How do you Tx spermatic cord torsion?Hemi-orchidectomy if long standing… want to protect spermatogenesis in contralateral testis. Sx & pexy
What does testicular (spermatic cord) torsion look like on U/S?
What is the major concern w/ scrotal trauma?Requires QUICK & AGGRESSIVE TX to prevent permanent damage to fertility due to compromised thermoregulation
How do you treat scrotal trauma?NSAIDs, AB’s (depending on cz); hydrotherapy. Consider Hemiorchidectomy to preserve the other testis
What are some nasty chronic changes which can happen due to scrotal trauma? (4)(1) Exposure of body to spermatozoa results in anti-sperm antibody formation
(2) Spermatic granuloma
(3) Testicular degeneration/atrophy
(4) Sub/Infertility
Testicular degeneration/atrophy is usually due to...Usually due to some sort of insult to testes (Eg. Hydrocele due to neoplasia/trauma; following Orchitis or trauma to testes)
What are the testes like in Testicular degeneration?Testes become softer than normal
What are the testes like in Testicular atrophy?Usually unilateral, Affected testis smaller & more fibrotic (Eg. Chronic Orchitis)
Testicular degen vs atrophy - which is SOFTER testes?Degen
Testicular degen vs atrophy- which is usually unilateral?Atrophy
What is Azoospermia?Complete absence of spermatozoa in the ejaculate
What are 6 major reasons for azoospermia? (& the top two?)Incomplete ejaculation
Plugged ampullae
Testicular degeneration
Retrograde ejaculation
Congenital hypoplasia of epididymidis, Genetic abnormalities (trisomy)
When do you usually see blocked ampulla? How is it usually dx?Usually at the beginning of the breeding season...Dx when Hx of mares not falling pregnant after covering, & semen eval reveals Azoospermia/oligospermia
How do you go about Tx of plugged ampullae? (4 things)Repeated semen collection, PGF, Oxytocin, Manual massage per rectum
What is preventative Tx you can do for plugge ampullae?Continue to collect semen on regular basis
What is Spermiostasis like following blocked ampulla?Initially only few dead spermatozoa (loose heads) in the ejaculate → When passage is restored, 1st very high concentration of dead spermatozoa (loose heads & some other abnormalities). → May take several days of daily semen collection to resume normal quality spermatozoa & establish normal DSO.
CSs of tear in pelvic urethra?Blood in ejaculate (hemospermia) No other CSs
Why do we care about blood in ejaculate (hemospermia) aside from the problem causing it?Affects fertility of ejaculate
How do you diagnose a tear in the pelvic urethra?Appearance of blood in ejaculate, Endoscopy, Usually tear in pelvic urethra

Venereal dzs

Question Answer
Coital exanthema is czd by what?EHV-3
How is Coital exanthema spread?Venereally Xmitted & by fomites
How does Coital exanthema present?External genital Infxn! Initially vesicles on external genitalia of stallions & mares → Then pustules, ulcers & crusts. May cz pain during coitus. Non-infectious once ulcers have healed – cz depigmented areas. Immunity short lived – re-infxn
If you see depigmented areas on the external genitals, what might you think?Coital exanthema ( EHV-3)
Tx for coital exanthema?Sexual rest & hygiene
Equine Viral Arteritis (EVA) → where does this like to live geographically?Endemic in Europe – Reportable in the US
How is Equine Viral Arteritis (EVA) Xmitted?By aerosols from acutely infected horses
****Venereally from carrier stallions
Via chilled/frozen semen (AI)
Indirect Xmission by fomites, feces, urine, vaginal secretions etc
How environmentally stable is equine viral arteritis?The virus is heat sensitive but is able to persist at freezing temperatures
How do the majority of cases present for EVA?The majority of cases are subclinical or unapparent
What are the major CSs of EVA?Signs of resp dz: Fever, depression, anorexia, leukopenia, Rhinitis, conjunctivitis, Urticaria; Edema of limbs, ventrum, periorbital region, scrotum, Abortion—associated w/ ‘abortion storms'
Who is a carrier for EVA?Mares, geldings & immature colts rapidly rid themselves of the Dz & develop immunity → Only stallions develop a carrier status
Why are only stallions carriers for EVA?Testosterone-dependent virus, Survives in ampulla, w/ a Variable duration (yrs or lifelong)
How do chronic carries shed EVA?Shed through semen in chronic carriers, but not through the respiratory tract.
How can you eliminate EVA (unique, not w/ drugs)Since TESTOSTERONE DEPENDANT, you can eliminate the virus by Suppressing testosterone for ≥ 6 weeks (GNRH??)
2 ways to Dx EVA?(1) Virus isolation incld whole blood, nasopharyngeal swabs, semen, conjunctival swabs, fetal or placental tissues/fluids
(2) Serology (paired samples)
Is there a Vx for EVA?YES! At-risk stallions re-vaccinated annually
What is something that is a problem w/ the VX for EVA Vx, & how do we try to circumvent this problem?Currently it is not possible to differentiate vaccinated from natural Infxn via serology which has implications regarding breeding shed access & export. So, Stallions are screened serologically before 1° Vx. CERTIFICATION OF NON CARRIER STATE.
What czs Contagious Equine Metritis?Czd by bacterium Taylorella equigenitalis
What economic impact does Contagious Equine Metritis have?Countries that don’t have CEM WILL NOT IMPORT YOUR HORSES!!! REPORTABLE IN THE US!
CEM- → Strict import quarantine & testing requirements → where do you take swabs, & what do you do w/ them?3 swabs taken from urethra, urethral fossa & lamina interna. In charcoal Amies media to reach lab w/in 48h. Sent for culture (OIE recognized) or PCR. Test breeding in USA
How is CEM spread?Xmitted venereally & by FOMITES
What are the CSs of CEM in STALLIONS?***Unapparent carriers
What are the CSs of CEM in MARES?Transient Endometritis post-breeding (Will usually clear themselves & develop transient immunity-- May (25%) become carriers)
Which is only males are carriers?EVA - bc testosterone dependent
*What are the 3 places swabs are taken from for CEM in STALLIONS?Swabs taken from urethra, urethral fossa & lamina interna
*What are the 3 places swabs are taken from for CEM in MARES?Swabs taken from clitoral sinus, clitoral fossa & endometrium
What medium is a CEM swab added to?In charcoal amies medium
Do you want to ship CEM swabs on ice? How quick should it get to the lab?Yes on ice, to lab w/in 48 hrs
How do you treat stallions for CEM?Daily scrubbing of penis w/ chlorhexidine & application of nitrofurazone or silver sulphadiazine ointment for 5-7 days. Application of dry-cow intramammary ointment into urethral fossa/sinus
When & how do you follow-up-test for CEM?One week after initiation of Tx the stallion is swabbed for isolation of Taylorella equigenitalis for 3 consecutive weeks.
What is "Test breeding" & where is this required?Required in the states, where a Stallion test bred to 2 mares → Mares swabbed (clitoral sinus, clitoral fossa & endometrium) 3 times – sent for culture. Following neg results, stallion can resume breeding
Pseudomonas aeruginosa /Klebsiella pneumoniae → how are these spread?Can be spread venereally to mares during coitus
Pseudomonas aeruginosa /Klebsiella pneumoniae → how do these affect the mare?Can cz Endometritis
What usually czs Pseudomonas aeruginosa /Klebsiella pneumoniae to become a problem for stallions?Overgrowth of these bacteria usually due to mismanagement of stallion during breeding (Eg. Overzealous washing of penis w/ disinfectants)
Dx of Pseudomonas aeruginosa /Klebsiella pneumoniae?Swab indicating pure growth – need to capsule type to determine if pathogenic or not
Dourine is czd by?Trypanosoma equiperdum (REPORTABLE in the US)
CSs of Dourine?Edematous swelling of genitalia, Mucopurulent urethral discharge, 2-10cm urticarial cutaneous plaques (“silver dollar” plaques). Progression emaciation, penile paralysis
2 ways to Dx dourine?(1) Complement fixation test
(2) Isolation of trypanosomes in urethral exudate, blood or urticarial plaques
Tx for Dourine?Generally impractical, euthanasia
Reportable in the US?EVA
Contagious Equine Metritis