Reproduction Manipulation Flashcards
How long after misalliance should you treat and what with?
7 days
What administration precautions must you be aware of with prostaglandin?
Causes abortion in pregnant women
Causes bronchoconstriction in asthmatics
At what time after service can you diagnose a pregnancy?
28 days
What drugs can you use as abortive agents and when will they work?
Prostaglandin - before 100 days
(Can give up to 150 days but the placenta starts producing progesterone after this)
Dexamethasone - best to use after 100 days
What is a risk to the dam if you abort / induce her?
RFM
How long does a cow need to recover post caesarean?
3 months
What are the rectal palpation findings in a pregnant cow at 3 months?
20mm cotyledons
Uterine arteries puny and pulsating
What are the findings from rectal palpation of a 4 month pregnant cow?
Cotyledons - 25mm
Uterine artery to pregnant horn is 2-3mm and has a thrill
What are the rectal palpation findings in a cow that is 5 months pregnant?
Cotyledons - 30mm
Uterine artery 7-9mm and thrill
What are the benefits of synchronising heifers?
Calve down 3-4 weeks early so they have more time to involute
Improves conception rates
Uniform calf size
Reduces disease spread
What length service period should the farmer use for cows vs heifers?
9 weeks (3 cycles) for cows 6 weeks (2 cycles) for heifers - need to synchronise
Discuss the advantages / disadvantages of Spring vs Autumn calving.
Spring calving - better fertility at first service as on a rising plane of nutrition, low BCS at calving as just overwintered = reduced dystocia, turned out on to lush pastures
Autumn calving - poorer fertility at service, can get fat before labour = dystocia risk
How should you advise a farmer manages his heifers?
Small heifers need to be 60% adult bwt at service
6 week service period (calve down 3w before adults)
Wean calf 1m early to allow for heifer growth
Calve down at 24m
Use smaller Bulls
Describe the 7 day co-sync protocol.
Indications - heifers that are already cycling
Day 0 - GnRH and insert PRID
Day 7 - remove PRID and inject prostaglandin
Serve 56-72h later and give GnRH at service
Describe an ovo-sync protocol.
Can be used in heifers that are not cycling but does not produce the best pregnancy rates.
Day 0 - GnRH
Day 7 - prostaglandin
Day 9 - GnRH
Day 10 - serve - 16-25 hours later
Describe a prostaglandin based protocol.
Day 0 - prostaglandin
Day 11 - prostaglandin
Serve in 72h
1/2 should come bulling with the first prostaglandin injection - serve these, then serve the other half after the second injection
Using a prostaglandin protocol with oestrus observation has a better pregnancy rate than fixed time AI
How can you synchronise beef cows that have calved at the end of their batch?
SIDR protocol.
Allow 6-8w sexual rest after calving
Day 0: SIDR inserted
Day 6: prostaglandin injection
Day 7: SIDR removed
What are the trade names of drugs used to manipulate oestrus?
GnRH (Receptal / chorulon) Im
Progesterone (PRID) Intra-vaginal
Prostaglandin - cloprosterol (Estrumate) Im
Prostaglandin - dinoprost (lutylase) IM
How many days in milk should a cow be pregnant by to maintain a 360 day calving interval?
80 days
When will you see a cow first in heat post-calving?
Ovulate a silent oestrus at around 14 days (low oestrogen due to underdeveloped follicles due to low progesterone)
Will first show oestrus at around 42 days (2nd cycle post calving)
When should you suggest routine fertility visits?
200+ cows - weekly
100-200 cows - every two weeks
100 cow - monthly
What animals should you see at a routine fertility visit?
Pregnant cows NSBs Post calving checks - at 21 days post calving History of abortion Additional checks for twins Problem cows
How long should the voluntary waiting period be?
50 days
What other methods of pregnancy diagnosis are available?
Palpation - from the 8th week
No return to oestrus
Ballottment
Blood tests
- oestrogen sulphate - from 52nd day
- progesterone in milk - robot milkers from 21st day
- pregnancy associated glyco-proteins - from 28 days
What is the normal size of an active CL?
Up to 30mm external diameter
A 30mm CL and smaller follicles suggest that the CL is dominant and follicles developing
- won’t ovulate until luteolysis occurs
What is the normal size of a dominant follicle?
Up to 25mm internal diameter (usually dominant at about 20mm)
How soon after giving prostaglandin will you see a cow come into oestrus with a dominant CL and developing follicles?
2-5 days
What is the benefit of giving prostaglandin to induce ovulation?
Shortens calving to conception
What is dioestrus?
Luteal phase
What is proestrus?
Coming up to oestrus
What is oestrus?
Oestrus signs, oestrogen high , progesterone low, LH causes ovulation to occur
What is metoestrus?
The period straight after oestrus when lutenisation occurs
What could you do if you find a dominant follicle on one ovary?
Tell farmer to observe for oestrus - billing string, standing to be mounted
Or give GnRH then serve
Signs of poor oestrus detection?
Long inter-service period (over 18-24 days)
Poor pregnancy rate
What methods of oestrus detection are available?
Observation for 3 and half hour slots per day
Pedometer
Tail paint
Scratch cards
Progesterone low in milk - robot milkers
Teaser bull
What will you see on vaginal exam when a cow has already ovulated / in metoestrus?
Vaginal discharge with flecks of blood in it
Closed cervix
When can you expect a resumption of cyclicity in beef cattle?
90 days
When can you expect a resumption of cyclicity in dairy cows?
2-3w
Ovulate a silent oestrus at 14 days
What will you find during proestrus on vaginal exam?
Closed cervix, a little bit of watery discharge
What will you find on vaginal exam during oestrus?
Open cervix
Bulling string
What size does a CL need to be to be responsive to prostaglandin?
Over 20mm
What are the risk factors for follicular cysts?
Negative energy balance Mastitis, metritis, lameness High BCS at drying off High parity High yielding Twins Periparturient problems Oestrogenic grasses
How can you treat a follicular cyst?
GnRH
Pop the cyst
Aspirate the cyst under u/s guidance
How should you treat a cystic CL?
Prostaglandin or
PRID
When would you suspect a twin pregnancy?
When you can see two CLs
What are the problems associated with twin pregnancies?
Freemartinism Reduced DMI - ketosis Reduces placental attachment LDAs Metritis Hypocalcaemia RFM
What are some differentials for poor fertility?
RFM Cysts Persistent CL Nutritional anoestrus Oestrus not observed Silent oestrus
At what stage of the oestrus cycle is the CL responsive to prostaglandin?
6-18
How soon after giving GnRH will the cow cow come into oestrus?
If developed follicles present - 2-3 days
Follicular wave about to undergo atresia - 4-7 days
