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.
List the main methods of oestrus detection in mares
CONSIDERATIONS
• If a mare is not in oestrus–> damage to stallion will occur: female will NOT accept stallion for mating if in proeotrus, female will kick out and cause an injury to stallion
• ‘Foal heat’ or ‘Foal shy’: if mare still has foal with her she may not show strong signs of oestrus- they are being protective of foal
Detection in mares:
• Detection of a large follicle (>20mm) in absence of a CL) (by palpation or ultrasound examination)- Mares ovulate when follicle is around 30-40mm in size
• Demonstration of follicle size, follicle wall thickening, follicle softening on ultrasound examination: Follicle changes in texture just before ovulation: soften and enlarge, walls become thicker: indicates best time to mate
List the main methods of oestrus detection in bitches
- Assessment of vaginal epithelial cells
- Assessment of vulval softening
- Examination of the appearance of the vaginal wall
- Cells chane in phenotype and composition at different types in the cycle
- Plasma progesterone concentrations (detecting a rise in progesterone that precedes ovulation), unusual, not seen in other species
- Measure progesterone levels from proestrus signs, when they begin to rise need to mate as oestrus will occur.
List the main methods of oestrus detection in queens
Oestrus detection is important for although the queen is an induced-ovulator (and ovulation will therefore not be missed), the LH response to mating decreases with each day of oestrus and follicles ultimately regress
Proestrus is short and often unnoticed
Describe reasons why oestrus may not be seen
Cows and low oestrus activity:
– Hard, non-supportive floor is best
– Concrete reduces oestrous behaviour by up to 50% especially when wet and slippery
– High environmental temperature: heat stress is a common cause of cows not showing oestrus signs, especially in countries with high temps
– Overcrowding
– Recent mixing / stress
– Lameness
– FEEDING
Anoestrus is seen due to:
• Gestation
• Lactation / presence of offspring will suppress oestrus in some species Note: species differences
• Seasonality: mares can enter anoestrus during winter months, spring time sees transition periods
• Stress suppresses oestrus behaviour
Metabolic
Heat
• Ovarian pathologies
Cystic ovarian disorders: can cause prolonged periods of anoestrus
Inactive ovarian activity
• Monoestrous breeders
e.g. bitches: have long periods of being anoestrus programmed into cycle
Silent oestrus:
=Ovulation with limited signs of oestrus
• Often at first oestrus after seasonal anoestrus / parturition
• No progesterone priming previously, brain needs to be primed with high progesterone levels so that it responds to rises in oestradiolm, giving rise to oestrus signs
• No progesterone fall
• No sudden release of oestrogen or LH suppression
Silent oestrus/ovulation?
Problem in cows: don’t show signs but ovulate anyway
more obvious in cows that are undergoing a greater negative energy balance
Management issues: misses oestrus
Breed effects: holstiens can show less signs of oestrus than other breeds (not proven with research)
