Oestrus signs and detection Flashcards
Describe the behavioural signs of oestrus in the cow
- After oestrus there is sometimes a red discharge representing blood seepage from caruncles
- Don’t show strong proestrus signs
Coming into heat: - Reduced milk yield
- Brawling, restlessness
- Chin pressing
- Vulval swelling, mucoid discharge
- Mount other cows
Oestrus: - Standing to be mounted, mount other cows
Describe the behavioural signs of oestrus in ewes
• Restless Seeks the ram, Forms a following harem • Stands for the ram waggles tail moves tail laterally to allow mating: induces phelman reaction in male • Vulva Slightly swollen Slight mucoid discharge
Describe the behavioural signs of oestrus in sows
- Vulval swollen and congested prior to oestrus
- Seeks the boar
- Stands firmly to be mounted: the back pressure test: placing pressure onto the sow’s back: if not in oestrus they will move away, if in oestrus they will remain still
- Stands for a smelly old boar that produces lots of saliva
- Restlessness with repetitive grunts
- Pacing and searching
- Lowered feed intake and loss of appetite
- Red, swollen vulva
- Male-like sexual behaviour
- Increase in vaginal mucus
- Response to boar pheromones: can buy can of pheromones ?(Boar Mate), will stand for mounting when sprayed
Describe behavioural signs of oestrus in mares
- Vulva: Oedema / mucoid discharge
- Elevated tail and lean her hindquarters towards the stallion, deviates tail
- “winking” (repeated exposure of clitoris)
- Induces “flehmen” response in stallion
- Commonly, daily teasing is performed
Describe the behavioural signs of oestrus in the bitch
• Proestrus: Very long (classically 9 days) Bitch is attractive but not allow mating: will present and show all classic signs but will not allow male to mate Vulval swelling Presence of a serosanguinous discharge (bloody discharge on vulva, not always seen as bitch often cleans it off) • Oestrus: 9 days Standing to be mated Deviation of tail Discharge becomes paler in colour Reduction in vulval oedema (swelling)
Describe the behavioural signs of oestrus in the queen
- Increased vocalisation, rubbing and rolling
- Increased activity and will seek tom
- Possible slight mucoid vulval discharge
Describe the relationship between oestrus and ovulation in cows
- Return to oestrus is reliable, very little variation
- Ovulation occurs at a repeatable time: timing is very tightly regulated and very well defined
- Oestrus is short, esp in the modern dairy cow, which can make it difficult to detect: if it occurs overnight it will be missed as occurs in a very short period of time
- Timing of insemination/mating: Relatively easy since oestrus is short and tightly regulated to time of ovulation- Inseminate/mate at oestrus
Describe the relationship between oestrus and ovulation in ewes
- Ewes have a shorter luteal phase than cows, and a longer oestrus
- Timing of insemination/mating: Not a problem since mated throughout oestrus by a ram. Key issue: correct ram:ewe ratio/identification of mated ewes. AI: insemination is slightly delayed (c.f. Cow): 12h after onset of oestrus
Describe the relationship between oestrus and ovulation in sows
- Have a similar luteal phase, longer oestrus
- Timing of insemination/mating: Sows / boars housed separately, sow presented to the boar for mating. Oestrus detection is very important. Mating and AI usually start on day 2 after the onset of standing oestrus.2 inseminations: 12-24 hours apart- ensures spermatozoa are within the correct part of the tract at the right time
- Ovulation occurs two-thirds way through oestrus; ovulation takes 2-4 h, means ovulation is over before the end of oestrus
Describe the relationship between oestrus and ovulation in mares
- Mares have a variable follicular phase (proestrus and oestrus vary greatly in length), which makes it difficult to know when to inseminate.
- Normal practice is to tease daily and breed throughout this period, or to monitor ovaries with ultrasound
Describe the relationship between oestrus and ovulation in bitches
- Bitches are a problem! – they are mono-oestrus: very long period between oestrus (an interoestrus phase following the luteal phase)
- Oestrus is very variable and signs relate very poorly to the time of ovulation.
- Oestrus detection is not very useful for planning mating and investigation of the time of ovulation based on vaginal cytology or plasma progesterone measurement is important
- If we miss the opportunity to mate a female, we will have to wait 7 months for another opportunity
- No fixed regime for ovulation: can be early but does vary, can change from season to season
- Difficult to know when to introduce male
- Can’t use oestrus signs to time breeding, must use other techniques: vaginal cytology and/or plasma progesterone measurement
- There is a very poor relationship between the serosangious dischargeseen during proestrus and the onset of oestrus, massive amount of variation (usually around 2 weeks but can be anywhere from 5-30 days) this is very difficult to manage
Describe the relationship between oestrus and ovulation in queens
• Proestrus: short & often unnoticed
• Induced ovulator
• LH response to mating decreases with each day of oestrus and follicles ultimately regress
Oestrus detection important
List the main methods of oestrus detection in cattle
Oestrus detection= critical: • Non-detection --> delayed breeding • Variable time for return to cyclicity • Job of herdsperson: Not usually run with a bull and so need to monitor behaviour to know when to introduce a bull • Detection rates <50% (ideally >80%) Strategies: • Examine cows at least 4 times per day • Detection aids e.g. Kamars, pedometers, Estrotect, GPS, electronic noses, paint/chalk • Van Eerdenburg’s scoring
• Pedometer: increase in activity due to restlessness oestrus
Clinical assessment/measurements:
- Low plasma or milk progesterone: when progesterone falls, signals either about to come into oestrus/is already in oestrus, not the best detection method but is useful
- Detection of a large follicle (and absence of a CL) by (palpation) or ultrasound examination of the ovaries
List the main methods of oestrus detection in ewes
– Only important when using an AI regimes
– Vasectomised ram with raddle mark used in AI systems (tease ewes into entering oestrus)
– Synchronisation protocols minimise need for oestrus detection- should all enter oestrus simultaneously
– Low plasma progesterone
List the main methods of oestrus detection in sows
CRUCIAL
• Need to ensure we present to boar/AI at correct time
• Consistent time of the weaning to oestrus interval (WOI), very useful e.g. weaning at 4 weeks ensures they will come into oestrus within the next 4-6 days
• Observations 2x day, remote from feeding time
Sows coming into heat soon after weaning (day 3-4) will show oestrus over 3 days, so insemination must be begun on day 2-3 of heat. Sows with an average interval from weaning to onset of heat (5 days) present a heat period of approximately 2 days and should be inseminated 24h after heat onset, with a second insemination to be done 12h later. Sows showing delayed heat after weaning (day 6 and beyond) tend to show heat only for a short period (1 day) indicating that insemination should be performed within 24h of heat detection.
