Repro formative case 2

Question 1

You are presented with a 3rd parity cow that has not been seen bulling since she calved. She is now 80
days in milk. You restrain the cow appropriately in a crush, and you are standing behind the cow to start
your rectal examination.
Describe the procedure of performing a systematic rectal examination in this cow to investigate her
reproductive tract.
Do this by listing five important steps you perform, after you have inserted your arm in the cow’s rectum.

Answer 1

Main points demonstrated in Moo tube video: ‘Female bovine repro tract’:

• *Start by identifying the pelvic floor/brim, followed by identifying the cervix (1):**
  1. run your hand from left to right over the pelvic brim to identify cervix
  2. retrace to cervix and identify both uterine horns and ovaries

Uterus:
Move up to each uterine horn in turn (1) and asses (1):
1. Size
2. Presence of fluid
3. Thickness of wall
4. Asymmetry

• *Ovaries:**
  1. Locate both ovaries(1)
  2. Feel for palpable structures (follicles, CLs) on both ovaries (1).

Marking criteria: 3 essential marks, including cervix, uterus and ovaries. If these are not listed you cannot
get the additional 2 marks; 2 additional marks can be gained from describing detail of the examination as
suggested, to a maximum of 5 marks in total

Question 2

These are your findings on rectal examination:
Left ovary: no significant palpable structures
Right ovary: no significant palpable structures
Uterus: present within the pelvic cavity, palpable tone on both uterine horns and the cow has a
string of clear mucous with specks of blood at the vulva.

At what stage in the oestrus cycle in this cow?
Justify your answer.

Answer 2

• *Stage:**
  1. Day 1-3, this cow has ovulated recently
  2. Cow is in metoestrus
• *Justification:**
  1. No structures palpable as corpus haemorrhagicum is short-lived (12-24 hours) and difficult to palpate
  (0. 5)
  2. Clear mucous with blood is an important indicator for ovulation to have recently occurred (0.5)
  3. Tone on uterus support your diagnosis of being close to/just past ovulation. (0.5)

Question 3

The farmer would like to get this cow pregnant.
Describe in detail three management and/or treatment options for this cow and list two advantages for
each of your options?

Answer 3

Option 1: do nothing and watch for oestrus (more closely, use heat detection aids (tailpaint, estrotect,
kamars, pedometers etc); she will come into oestrus in approx 17-21 days.
Pro:
1. no intervention
2. no Tx cost

Option 2: ‘ovsync’ (need to specify protocol!) day 1 GnRH, day 7 PGF2a, day 9 GnRH, blind AI 16 hours
after GnRH injection.
Pro:
1. Fixed time AI, reasonable conception rates (30-50%) in cycling cows that don’t show heat
2. Works irrespective of stage of cycle
3. Earlier service compared to waiting for natural heat

Option 3: CIDR/PRID & PGF2a; the vaginal insert should be left in for at least 7 days with injection of
PGF2a administered 24 hours prior to removal. Oestrus generally occurs within 2-4 days after removal of
the insert.
Pro:
1. Earlier service opportunity compared to no Tx
2. Observed oestrus serve gives better conception rate than fixed time AI
3. Added progesterone may increase chance of conception compared to GnRH/PG only in high yielding
cows.

Option 4: 1xPGF2alpha 7-14 days after examination, use heat marker to observe oestrus, serve on
observed heat in approx 3-5 days.
Pro:
1. Easy to manage
2. Relatively cheap, although vet visit required administer PG
3. inseminate on observed oestrus gives better conception rates compard to TAI
4. Earlier service opportunity compared to no Tx

Option 5: Run with bull
Pro:
1. Easy intervention
2. Cost effective if bull present

Option 6: AI her asap
Pro:
1. Small chance that the semen will reach the oocyte in time for fertilization; however, most times it will
be too late.
2. Quick

Any sensible combination of a progesterone device with GnRH and/or PGF2alpha (eg. CIDR
sync=ovsync with CIDR for 1st 7 days) may create earlier ovulation compared to waiting for a natural
observed oestrus. GnRH/PGF2alpha increase chances of successful AI because of more defined
window of time to expect to observe oestrus/ovulation (ie. the farmer knows to look for heat in that cow
for around 2-3 specific days instead of leaving it up to her natural cycle which may be more variable)

Question 4

Give two pieces of information you need from your client to best advise him on the most suitable
management/treatment option for the cow.

Answer 4

• Assessment of the heat detection ability on farm (to decide on blind/timed AI vs observed oestrus AI)
• Identify importance of cost (doing nothing may seem cheap short term but could be more expensive
• long term, as it may lead to more days open)
• Attitude towards using drugs to induce oestrus, as it is not essential in this case, it is merely used for
• cost effectiveness, and there appears to be no disease/abnormality present. Type of farming
• conventional vs organic will limit possibilities.
• Does he have fortnightly routines? Can you fit PGF2a injections in the routine to manage cost, so you
• don’t have to charge a separate visit to PG 1 animal?
• Any other health/fertility history features about the cow. How is reproductive performance in general,
• what are his goals for calving index? (to assess how important early intervention is)
• What value semen is being used
• Is the herd block calving and if so where we are in the service window.