Reproduction Flashcards
What pathology can occur with the scrotum
> Often dermatitis associated - E.g choriopitic mange in rams
Thermoregulatory failures - Leading to fertility issues
Neoplasia - Commonly MCT or haemangiosarcoma in dogs and papilloma in boars
What pathology can occur with the tunica vaginalis
Thin Mesothelium around the testis that is continuous with the peritoneum. Therefore acitis can be associated with hydrocoele.
Can also get inflammation of the tunica vaginalis - Periorchitis
What pathology can occur with the testis
> Intersex conditions
- Male pseudohermaphroditism - External female genitalia and testes in the position of the ovary
- True hermaphroditism - Animals have one testi and one ovary or combined
> Cryptorchidism - Testes retained between kidney & inguinal canal. Usually unilateral. Likely polygenic cause ( genetic + environment). Testes often small and fibrotic which increases risk of tumour formation.
> Testicular hypoplasia - Congenital or prepuberty (wont notice until after puberty). causes include: Zn deficiency, genetic, endocrine.
> Testicular atrophy - Occurs post puberty. Most common cause of infertility! Unilateral = Local and bilateral = systemic. causes include Increase in testicular temp, decrease in blood supply, hyperoestrogenism or vitamin A/zinc deficiency.
> Inflammation of testis - Very rare. 3 possible causes:
- Haematogenous - E.g brucella abortus
- Trauma - Dog bites, often associated with periorchitis & epididymitis.
- Reflux orchitis - Extention of inflammation from the epididymis, prostate, urethra or bladder
*Loss of blood testes barrier will result in granulomatous reaction, because spermatozoa are haploid = seen as foreign
What pathology can occur to the epididymis
Epididymitis
> Mainly an ascending infection from urogenital tract or accessory sex glands
> Enlargement often followed by abscess & granuloma formation
> Degree of testicular atrophy & degeneration due to pressure + heat
> Often a mixed infection involving coliforms, staphylococci and streptococci
Describe the 3 types of testicular neoplasia that can occur
- Leydig cell (interstitial) tumour - usually effects >8year. grossly appear as spherical, orange/greasy haemorrhagic masses. Bulge on cut surface. No enlargement of testes - Benign.
- Sertoli cell tumour - usually effecting >6years, 20x increase in occurrence with cryptorchidism. Usually unilateral, with a firm lobulated discrete mass that causes testicular enlargement. Around 25% secrete oestrogen and can cause hyperoestrogenism ( causes attraction to other males, mammary swelling, symmetrical alopecia, atrophy of testis. 10% metastasise
- Germ cell tumour - Seminoma, derivered from spermatogonia. Usually unilateral and grossly look like a soft cream mass, with a bulge on cut surface.
* Teratoma - Effects young horses, tumour originates from totipotential primordial germ cells.
Describe possible pathology to the accessory sex glands
> Hyperplasia of prostate - Occurs in old entire dogs. Causes constipation and/or urinary stasis. Castration causes atrophy as its hormone dependent
> Metaplasia of prostate - Glandular epithelium changes to squamous cell epithelium. Predisposing to inflammation.
> Prostatits - Often associated with hyperplasia. Mostly due to an ascending infection, invading the prostatic urethra. If left untreated can lead to peritonitis and septicaemia
> Neoplasia - Mostly a carcinoma occuring >10years. Castration not effective. Will cause constipation and urethral blockage. Possible locomotor issues if it compresses SC. High rate of local reoccurence or metastasis to LN’s, lung and bone
What pathology can occur to the penis and prepuse
> Venereal transmitted diseases - Tritrochomonas foetus - Causes infertility, early embryonic death & metritits in cows. Diagnosed by sheath washings and culture
> Non inflammatory diseases:
- Direction deviations
- Hypoplasia with early catsrations
- Haematomas
- Paraphimasis - Inability to retract penis
> Inflammatory conditions:
- Balanitis - Glans penis inflammation
- Posthitis - Inflammation of prepuce
Can occur together - Balanoposthitis - Infectious cause in bull known as Bull infectious balanoposthitis
What neoplasia is common on the penis
> Squamous cell carcioma - Most important in horses. Associated with equine papillomavirus type 2. Has a low grade of malignancy and will reoccur if not completely removed
> Fibropapilloma - Glans penis of the bull (1-2years) caused by bovine papillomaviruse type 1
> Transmissable venereal tumour - histocytic origin ( abnormal amount of chromosones). Prone to ulceration and secondary infections
What could vulval discharge indicate (SA)
Age and & neutered status is key! also important to know stage of reproduction cycle.
> Mucopurelent white - Could indicate a vaginitis, open pyo or early metoestrus.
> Haemorrhagic - Proestrus/oestrus, cystitis, persistent follicle or ovarian/urethral neoplasia
> Greeny black - Parturition (normal) or dystocia
> Brown/red/black - Metritis
What is vaganitis
> Occurs in juveniles (pre-puberty)
will resolve under the influence of oestrogen (1st cycle).
Due to bacterial contamination & excess vaginal secretions
Describe the difference between open and closed pyometra and its cause
Usually presents withing 8 weeks of the last oestrus
> Open Pyometra - Mucopurolent vaginal discharge & mild-moderately enlarged uterus
> Closed - Closed cervix therefore no vaginal discharge associated. Uterus grossly enlarged and animal is systemically ill
Cause?
>Cystic endometrial hyperplasia provides good environment for bacterial proliferation
> Bacteria from faecal cotamination (E.coli), generally when cervix is one during oestrus
> Then during diestrus increase in progesterone causes immunosuppression & increased bacterial proliferation
Blood profile
- Neutrophilia with Left shift
- Acidosis
- Endotoxaemia
- Hypoglycaemia
- Anaemia
- Coagulopathies
What is the most common vaginal neoplasia and how is it treated
Smooth muscle tumour of the vagina/vestibule - Leiomyoma or leiomyosarcoma. Slow growing benign tumours, can present with visible bulging at perineum, dysuria and dyschezia
Treatment includes surgical excision of mass + ovariohysterectomy
What may be a cause of vaginal prolapse in SA and what breed is predisposed
Vaginal oedema due to excessive response of vaginal mucosa to oestrogens during the follicular phase.
Brachycephalic breeds predisposed, and tends to reoccur during subsequent oestrus’s
How is dystocia determined in SA, what are the causes and how is it managed
Cause for concern when:
> Fetal fluids passed but no birth in 2-3 hours
> Weak and irregular straining for 2hours with no birth
> Last pup/kitten was 2-4 hours ago
Maternal causes include narrow birth canal, uterine abnormalities (torsion/rupture/malformation), or uterine inertai
> Primary inertia - Uterus fails to respond to foetal stress
> secondary inertia - Exhaustion of the myometrium or Secondary to obstruction of birth canal
Management: Only when theres no sign of obstruction
> Feathering the roof of the vaginal floor
> Repeated (30-40mins) of small oxytocin doses (0.2-0.4Iu/kg)
> Treatment of hypocalcaemia if present
What is paraphimosis and when/how can it be treated
Non erect protruding penis (differs from priapism as this is a constant erection due to block in draining veins). Due to abnormally narrow preputial orifice, short prepuce or weak retractor muscle.
Treatment if penis becomes ischaemic, then a penilostomy + urethrostomy ( new urinating opening)
What is hypospodias
Congenital abnormality causing incomplete formation of penile urethra
What is phimosis
Inability to protrude penis beyond preputial orifice . surgical enlargement of preputial orifice possible
What are the possible reasons for prostatic enlargement excluding neoplasia
> Benign prostatic hypertrophy (BPH) - Normal ageing change in entire males, testosterone dependent. Castration cause involution withing 3-12 weeks.
> Prostatis/Prostatic abscessation - Common in dogs. associated with a purulent urethral discharge, a systemically ill patient, Dysuric (painful urination). Need to drain (syringe + 3 way tap) to avoid septic peritonitis
> Prostatic (inside body of prostate) & para prostatic (outside body) cysts - Generally an incidental finding to UTI patient thats more systemically ill than expected. Biopsy should be taken to rule out neoplasia
What are typical properties of prostatic neoplasia, how is it diagnosed and how is it treated
More common in neutered dogs. Common types are adenocarcinoma and transition cell carcinoma
Tend to be locally invasive and metastatic (commonly bone formation on the wing of ileum)
Clinical signs include dysuria, pain, weight loss & dyschezia.
Diagnosis based on ultrasound guided biopsy - poor prognosis
Treatment includes - Urethral stent, NSAIDS, cystostomy tube
How can you Induce ovulation in seasonally anoestrus ewes or anovulatory post partum cow
> Cow - Use a controlled internal drug release (CIDR) for 12 days, then on the day of removal give 500iu of eCG to increase LH pulse frequency.
> Ewe - Progesterone sponge for 10-12d then 500iu injection of eCG. Present to rams 24 hours later.
How can you induce puberty in gilts
Intramuscular injections of PMSG + hCG at 6/7 months (100kg). Has no effect on LH/GnRH, binds directly to granulosa cells acting like LH/FSH
Give 3 ways in which oestrus can be synchronized
- PGF2a - Ideally injection at day 10 of oestrus cycle, CL is refractory up to day 6, therefore 2 injections are given 10-11d apart to ensure it meets a responsive CL.
- ‘Ovsynch’ - Give GnRH to synchronise a new LH wave. 7days later give PGF2a causing luteolysis. 2nd GnRH dose given 2 days after Prostaglandins, synchronizing LH surge in all animals, can be AI’d in 24 hours.
- Use CIDR & remove at day 12 with a PGF2a dose.
In cows, what are the treatment options for
- luteal cysts
- Follicular cysts
- pyometra
- Luteal cysts - Prostaglandins
- follicular cysts - GnRH
- Pyometra - Prevents PGF2a causing a persistent CL. Therefore intramuscular PGF2a
How can parturition be induced in Large animals
Intramuscular injection of dexamethasone - parturition 3-5 days later
How can you try to increase number of gametes in sheep
Aim to decrease atresia or increase follicular recruitment.
> eCG is a recombinant FSH = superovulation
> Also can flush, so increase plane of nutrition which causes and increase in hepatic portal circulation and increase in metabolisation of steroid hormones. Leads to a decrease in eostrogen and therefore no negative feedback on FSH.
Describe 3 ways in which immunology is used to control reproduction in LA
> Immunisation against androstendione - Pre cursor to oestrogen. Therefore removes negative feedback on hypo-pituitary causing an increase in FSH, increase in recruitment and follicles and therefore an increase in ovulation rate
> Immunisation against GnRH - Inhibits LH and FSH production causing a decrease in testicular size and function. Practised to help comntrol aggression and reduce male associatyed odours
> Spayvac - Ig’s bind to ZP, preventing sperm binding
How can eostrus be controlled in the bitch
> Synthetic prostagen - Medroxyl progesterone acetate. Side effects include increase growth hormone (can cause acromegaly), Diabetes melitus and mammary tumours
> Proligestone - Synthetic prostagen that is stongly anti-gonadotrophic, weakly prostagenic and antioestrogenic (doesn’t have associated side effects of medroxyl progesterone acetate, control vulval swelling and bleeding)
> Testosterone - Can give orally but effects fertility & causes protrusion of the clitoris and enlarged vulva
What are signs of clinical pseudopregnancy in the bitch and how is it treated
> Clinical signs - Weight gain, mammary development & behavioural changes. Also a associated rise in prolactin
> Treatment - synthetic prostagens keep progesterone high and suppress prolactin. Can also use a dopamine agonist which will inhibit prolactin, however this can induce vomiting.
How is eostrus controlled in the queen
> Progesterone can be given as soon as calling starts
> hCG - Induce ovulation & delay subsequent calling because queen goes through pseudopregnancy
What are the possible the reasons for no observed oestrus?
> Congenital abnormalities such as ovarian aplasia or hypoplasia
Ovarian cysts
Cyclical ovarian activity but no behavioural signs (silent heat )
Signs of oestrus not detected due to staffing issues
Persistent CL (+ pyometra?)
- Should display signs of oestrus every 18-24days or 4-6 weeks post partum
What is a free martin cow
Hermaphrodite or imperfect sterile female calf who was a twin with a male (share same chorioallantoic sac). Hormone from male calf effected development of female calf.
Diagnosed by the history of twin birth with a male + short vagina (stick a probe in and doesn’t go far)
What reason may a cow be in anoestrus
> Increase in milk yield such that animal doesnt have enough energy to cycle
Decrease in BCS
Stress e.g lameness
Inadequate nutrition - Cause a decrease in IGF-1 = decreased GnRH = Decreased LH/FSH = Decreased ovarian function
- To treat wait until milk yields begin to decrease so cow can go back into a positive energy balance and increase he amount of concentrates - This can be accompanied by Controlled internal drug release (CIDR)
What is the size of a normal follicle and what are the different types of cysts in cattle and how are they treated
A normal follicle is no bigger than 1.5-2cm. CL can become vacuolated which is normal.
> True follicular cyst - Thin walled & >2.5cm in diameter. Secrete oestrogen - Give GnRH = high amount of LH = luteinisation
Luteal cyst - Thick walled (>3mm) and diamater of 2.5cm. Progesterone secreting - Treat with PGF2a
Thin walled functionally undifferentiated cysts are inactive.
