Flashcards in Bovine Deck (459)
What factors affect the normal involution of the uterus?
2. Retained placenta
3. Uterine infection
6. Selenium deficiency
7. Suckling frequency
9. Climate - heat stress
What is post partum vaginal discharge called?
normal for 7-10 days due to sloughing of surface tissue from uterine caruncles. Usually reddish brown and odourless. It is derived from the remains of the foetal fluids, bloods, shreds of foetal membranes but mainly from sloughed surfaces of caruncles. Complete regeneration of caruncular epithelium normally achieved by 25 days pp. Caruncles gradually shrink as involution progresses.
What are the most common bacteria isolated from the uterus?
actinomyces pyogenes, e coli, fusibacterium necrophorum, staph, streps. 90% of uteri swabbed within 15 days post calving have bacterial contamination but this is reduce to around 9% by 46-60 days pp.
Why may bacteria fail to be eliminated from the uterus?
Due to overwhelming degree of bacterial contamination or impaired natural uterine defence mechanisms.
What is puerperal metritis?
Puerperal metritis should be defined as an animal with an abnormally enlarged uterus and a fetid watery red brown uterine discharge, associated with signs of systemic illness and fever >39.5C, within 21 days after parturition. often associated with RFM?
What is the treatment for puerperal metritis?
Systemic broad spectrum antibiotics eg cephalosporins. If toxic shock present give i/v fluids and flunixin.
Why may removal of RFM be contraindicated in puerperal metritis?
Increases uterine trauma and toxin absorbtion, prostaglandin injection may be beneficial when calved 10-14 days.
What is metritis?
Animals that are not systemically ill but have an abnormally enlarged uterus and a purulent uterine discharge detectable in the vagina, within 21 days post partum may be classified as having clinical metritis.
What is clinical endometritis?
Characterised by the presence of purulent uterine discharge detectable in the vagina 21 days or more after parturition. No systemic illness.
What are the predisposing factors associated with endometritis?
Dirty calving environment
Premature calving - twins induced calving
Delay in return of pp cyclicity.
Over fat at calving/fatty liver syndrome
Nutritional deficiency eg selenium
what are the consequences with clinical endometritis?
Extending calving - conception interval in affected cows due to delay in return to cyclicity or deliberate delay in re breeding plus reduced conception rates due to hostile uterine environment causing semen/embryo death.
How Can endometritis be diagnosed?
Evident at three to four weeks post calving by persistent purulent vulval discharge, often evidence of tacky discharge stuck to tail below vulva. May be seen following oestrus when cervix opens. Rectal palpation normally reveals one or both uterine horns enlarged but may be little palpable abnormality in mild chronic cases. Ultrasound is useful to aid diagnosis with distension of the horn and purulent fluid being evident.
What is the treatment of endometritis?
Prostaglandin injection - treatmnet of choice. requires responsive CL for optimum effect.
Intrauterine antibiotics - pessaries of dubious efficacy due to insufficient concentrations of antibiotic administered, metricure washout preferable, can try 12-24 hours after AI in repeat breeder cows if suspect low grade endometritis.
Antiseptic wash out - irritant to endometrium and cause PGF2a release which may have curative effect.
How can endometritis be Prevented?
Environment - general calving hygiene and minimise dystocia problems.
Host immunity - physical barriers, acquired immunity, innate immunity
Pathogens - coli, a pyogenes, anaerobes,
Avoid over fat cows
ensure adequate mineral/vitamin supplementation.
What is a pyometra?
Defined as the accumulation of purulent material within the uterine lumen, in the presence of a persistent corpus luteum and a closed cervix. Will palpate distended uterine horn which must be distinguished from pregnancy as could develop after service. With pyometria uterine wall is often thicker and no membrane slip or cotyledons palpable. Can confirm using ultrasound.
What is the treatment for pyometra?
Injection with PGF2a with luteolysis being followed by return to oestrus and evacuation of the uterus.
What is retained foetal membranes?
Partial or complete retention of foetal membranes beyond 12 hours post partum. effectively this means failure of normal 3rd stage labour. Failure of normal separation of foetal cotyledonary vili from maternal caruncles or primary uterine intertia. Phsyiological processes controlling separation of placenta begin weeks pre partum.
What factors predispose to RFM?
Premature parturition - immature placentomes not physiologically prepared for separation eg twin births, late abortions, induced births.
Oedema of chorionic villie caused by trauma eg dystocia, caesarian, uterine torsion.
Pathological inflammation eg placentitis caused by abortion agent such as bacillus licheniformis.
Uterine inertia due to hypocalcaemia, hyposelenaemia, hydrops, twins.
What are the clinical signs of RFM?
Putrif placenta hanging out from the vulva, but may be retained in the cervix/vagina and not obvious from outside. May be straining in attempt to pass the placenta. Usually no systemic illness unless puerperal metritis develops.
How can RFM be treated?
Manual removal probably contraindicated unless comes away with gentle manual traction. Best time to attempt manual removal is 3-5 days pp. Definetly contraindicated if associated with metritis as causes trauma to endometrium which may increase toxin absorption and decrease phagocytic function. If puerperal metritis is present appropriate systemic antibiotics will be needed.
When do most ovarian cysts develop?
20-60 days pp often in 2nd and 3rd lactation high yielding cows.
What is the definition of an ovarian cyst?
Fluid filled structure >2.5cm diameter present for >ten days on one or both ovaries in the absence of a CL.
What are the two types of ovarian cyst?
Follicular - thin walled, non progesterone producing
Luteal - thicker walled, progesterone producing.
Why do ovarian cysts form?
Cysts form due to failure in LH surge around the time of ovulation, or failure of follicle to respond to LH. Folicle fails to ovulate and instead of becoming atretic continues to grow and forms cysts. Cystic follicles initially produce oestradiol which suppresses further follicular development and then they may enter oestrogen inactive phase during which time the cyst can persist for many weeks.
What are the possible reasons for the failure of LH surge to cause an ovarian cyst?
Sterss - cortisol can interfere with lh surge. eg energy stress, movement, change of diet.
Metritis - also causes cortisol release.
What are the clinical signs of a follicular cyst?
Anoestrus or occasionally nymphomaniacal behaviour i.e irregular or recurrent oestrus behaviour
Luteinised cysts: anoestrus
Most cysts cause anoestrus and are detected on routine pp checks .
How can you diagnose ovarian cysts on milk progesterone?
follicular cysts have low milk progesterone 2ng/ml.
What is the treatment for ovarian cysts?
Progesterone - PRId for 10-12 days. Causes atresia of cyst by suppression of LH and FSH through progesterone negative feedback.
PGF2a - can use alone if luteal cyst.
If positive it is a luteal cyst - use PG
if positive it is a follicular cyst use a PRID/CIDR for 10-12 days or GnRH injection.
If unsure of cyst type use GnRH + PG in 7-14 days if not seen in oestrus or insert prid for 10-12 days with injection of PG at removal.
What is the definition of abortion?
The expulsion of a dead or non viable calf before 260 days gestation.