Post partum disease in cattle Flashcards
What happens between calving and successful establishment of next pregnancy?
1) involution of the uterus (after expulsion of calf and placenta)
2) restoration of the endometrium
3) resumption of ovarian cyclicity
4) Insemination
5) Fertilisation = conception in a timely manner
6) Maintenance of the pregnancy
7) Calve again
What happens to the endometrium post-partum?
- 48hrs post partum = septal mass, stretched stratum compactum + thick myometrium
- 5 days post partum = sloughing of necrotic septal mass
- 10-15 days post partum = necrotic septal mass sloughed + vascular stubs on stratum compactum
- 19 days post partum = smooth surface of stratum compactum + shrinking
What needs to be avoided with a c-section?
- Avoid caruncles = V vascular
When does resumption of cyclicity occur?
Puberty
Onset of seasonal breeding (N/A in cows)
Recovery from NEB
Post parturition - cows have increase in FSH which stimulate follicular wave
What is normal ovarian function post-partum in cows?
Low progesterone and oestrogen after calving
Resumption of FSH surges increases within 3-5 days, at 7-10 day intervals
1st post partum follicle wave –> 1st Dominant Follicle
Does the 1st Dominant Follicle ovulate?
- yes if sufficient E2 from the DF for LH/FSH surge
-Capacity for E2 secretion depends on =
1. size of DF
2. LH pulse frequency (nutrition, health)
3. IGF-I bioavailability (nutrition)
What can be used for oestrus detection?
- Visual observation
- Tail-head markers (stickers/chalk)
- Activity meters
- Progesterone monitoring
- External technician (single job to do)
- Bull/Teaser bull
What occurs with embryogenesis?
- Day 0 = fertilization
- Day 1 = 2-cell
- Day 1.5 = 4-cell
- Day 7-12 = blastocyst
- Day 13-35 = elongated blastocyst
What are reasons for failure of fertilisation + embryonic loss?
- Failure of fertilisation - AI technique/timing, oocyte quality/health
- Uterine environment
- Infectious agents (BVD, BHV1, Lepto, Campy)
- Metabolic status of dam / nutrition (Pre/post calving)
- Genetic abnormality of embryo
What goes wrong after calving as seen by the farmer / vet?
- Retained Foetal Membranes
- Metritis / Endometritis
- Cystic ovarian disease
- Failure to resume ovarian cyclicity = non-buller/NSB/ONO (or failure of detection???)
- Return to oestrus (on time or not on time) Insufficient IFT production = fails to implant = Embryonic death (early / late)
- Abortion
What are different uterine infections?
- Metritis
- Endometritis
- Pyometra
What are the consequences of uterine infections?
- Damage the uterus
- Suppress hypothalamic GnRH + pituitary LH secretion
- Have localised effects on ovarian function
What are the main pathogens for uterine infections?
- E.coli (Gram Neg)
- Truperella pyogenes (Gram Pos)
- Dichelobacter nodosus (Gram Neg)
- Fusobacterium necrophorum (Gram Neg)
- (BoHV4)
What are risk factors for uterine bacterial infection? (in order)
- Retained foetal membranes
- Abortion
- Dystocia
- Twins
- Induction
- Milk fever
- Multiparous (older cow)
What is metritis?
- an abnormally enlarged uterus and purulent uterine discharge detectable in the vagina, within 21 days after parturition
What are the grades of metritis?
- Grade 1 = enlarged uterus and a purulent uterine discharge but no pyrexia
- Grade 2 = ‘puerperal metritis’ - overt systemic illness (decreased milk yield, fever, >39.5oC, reduced appetite)
- Grade 3 = ‘toxaemic metritis’ - signs of toxaemia (cold extremities, dullness)