Reproduction Flashcards
1
Q
Oxytocin should not be used in which species?
A
Cattle
2
Q
Describe the second stage of labour in cattle
A
Delivery of the calf
Begins with the appearance of the water bag (membranes) at the vulva
May last several hours
Water bag ruptures, cervix dilates with further pressure from calf
Powerful reflex and voluntary contractions of abdominal muscles and diaphragm serve to expel the calf
3
Q
Describe the third stage of labour in cattle
A
Expulsion of placenta
Usually happens within a few hours
If not expelled within 12 hours of delivery of the calf, referred to as Retained Foetal Membranes (RFM)
4
Q
How big should a calving pen be?
A
12 feet x 12 feet
5
Q
What properties should a calving pen have?
A
Size= 12 feet x 12 feet Easy to clean out between calvings A gate, perhaps with a quick release headlock Milking facility Well-bedded and dry Good access to food and water Good lighting Well ventilated and in a quiet area of the farm
6
Q
When should you intervene during calving?
A
Only if:
No progress has been made after 1 hour of the water bag showing
Has not progressed to second stage labour after 6 hours (possible twisted uterus)
Cow appears in extreme discomfort
Significant bleeding from vulva
7
Q
Why should you not intervene too early when the cow is in first stage of labour?
A
Can prevent full dilation of cervix
8
Q
Give some causes of bovine dystocia
A
Foeto-maternal disproportion (heifer impregnated by bull, nutritional, iodine deficiency can lead to longer gestation), dead calf
Malpresentation of calf
Incomplete cervical/vaginal dilation
Uterine inertia (lack of effective contractions; hypocalcaemia)
Uterine torsion (rotation around long axis)
Cervical prolapse
Pelvic fracture
Uterine rupture
Cervical neoplasia
Congenital abnormality (eg spina bifida)
Bull calves more likely to be dystocic
9
Q
Describe the first stage of labour in cattle
A
DILATION OF CERVIX
May take 3-6 hrs
Cow separates herself from herd
Appetite decreases
Alternates between lying and standing
Thick string of mucous often seen hanging from vulva
Towards the end, bouts of abdominal straining occur every 2-3 minutes
Abdominal straining pushes uterine contents against the cervix, giving it further stimulation to dilate
10
Q
How should you approach bovine dystocia?
A
Restrain
Clean (prevent bacterial entry -> endometritis)
Lubricate
Identify problem
3 R’s: Reposition (calf or uterus), repulsion, rotation
Extract
11
Q
Which drug can you use to relax the uterus during bovine parturition?
What are some problems?
A
Clenbuterol
Wont help in delivery-will stop cow contracting
Increases uterine blood perfusion- calf survival?
12
Q
When might you need to call for back-up during calving?
A
Caesarean True breech Twisted uterus Lots of bleeding You don't make progress within 20 mins of trying to calve dam
13
Q
Where should you position ropes/chains when pulling out a calf?
A
Double loop: one above fetlock (metacarpus/tarsus), one below
Minimal chance of leg fracture or rope slipping off
Use different coloured ropes for different legs so as not to twist them/mix them up
14
Q
What would tell you that a calf is too big to be delivered per vaginum?
A
Forelimbs crossing over meaning shoulders are too large to pass through pelvic canal
Head can’t be brought into the pelvis or remain there once traction is released
Not enough room for a hand to be passed between the foetal cranium and maternal sacrum
Unable to exteriorise each fetlock
15
Q
How would you correct a carpal flexure malpresentation during calving?
A
Push leg back with one hand, use rope or other hand to pull foot forward
16
Q
How would you correct a calf with its head back during calving?
A
Push calf back to give more space, and allow head to fall into correct position between legs
Use head rope to prevent head falling back
Clenbuterol
17
Q
How can you see if a calf is alive during calving?
A
Flick tail
Check anal reflex
18
Q
How do you correct breech presentations during calving?
A
Repulsion of perineum
Cup the foot over the pelvic brim (take care with hock-pressure on spine)
19
Q
Regarding cows, are twins more likely to abort if in the same horn or different horns?
A
Same horn
20
Q
What is an episiotomy?
When is it used?
A
Incision in perineum (tissue between vagina and anus)
Calving heifers: if vulva is not fully dilated but cervix is dilated and calf is entering pelvic canal
Try manually stretching vulval lips with arms for 20 mins before resorting to episiotomy
Contamination risk high-give antibiotics
Caudal epidural anaesthesia
Make incision when calf’s head is passing through vulva
21
Q
Where should you cut when performing an episiotomy?
A
10-11 o’clock or 1-2 o’clock
Not 12 noon -> recto-vaginal fistula
22
Q
What are some possible complications of an episiotomy?
A
Wound infection and breakdown
Distorted vulva conformation (pneumo-vaginum, uro-vaginum)
Weak point to muscles which may affect ability to calve naturally in the future
Rectovaginal fistula if cut at 12 noon
23
Q
What is required to perform an embryotomy/foetotomy?
A
Must have sufficient space within vagina and pelvic canal Caudal epidural anaesthesia Clenbuterol Lubrication Good equipment
24
Q
When would you perform a full embryotomy?
A
Large dead calf
Foetal monster
25
When would you perform a partial embryotomy?
Hip locked in pelvis (cut off trunk as close to vulva as possible, split pelvis with wire)
Head back - unable to correct and calf dead (remove head)
Leg back - unable to correct and calf dead (remove leg using 'passing' method; must ensure elbow, shoulder and scapula are removed otherwise no narrowing is achieved)
26
What are the two methods of cutting through a dead calf during calving?
Passing
| Cleating
27
Give some complications of embryotomy/foetotomy
```
Uterine tears
Cervical tears
Vaginal tears
RFM (retained foetal membranes)
Metritis
Adhesions
```
28
Briefly describe how you'd perform an embryotomy/foetotomy
Remove head using 'passing' method of wire placement (cut as far caudal along neck as possible)
Remove forelimb (ensure scapula removed)
Remove thorax using 'passing' method (remove as many vertebrae as possible in one cut)
Remove rest of trunk
Split pelvis using 'passing' method
Extract one hindlimb at a time
29
When do most uterine torsions occur during calving?
Onset of parturition
30
What are the risk factors for uterine torsions?
```
Poor rumen fill
Space in the abdomen
Hilly land
Process of standing up/lying down
Majority are anti-clockwise torsions (whens stood behind cow)
```
31
How may a cow appear if she has a uterine torsion?
Appear to start calving but no progression
No straining as Ferguson's reflex is not stimulated
Slightly raised tail
Dry cow off colour/down/toxic
32
How can you correct a bovine uterine torsion?
'Swing' calf with coordinated ballotment of abdomen whilst holding calf
Twisting the calf's legs may twist the uterus too
Roll cow (usually from left lateral recumbency -> back -> right lateral recumbency) (grab calf's leg if you can whilst rolling cow or hold with calving rope or place plank across abdomen during rolling)
Caesarian (if can't untwist uterus)
33
Name some complications of uterine torsion
If high degree torsion, the blood supply can be occluded -> friable tissue at torsion site
Dead emphysematous calf and toxic cow
34
What are the indications for performing a caesarian section on a cow?
Foeto-maternal disproportion
Irreducible uterine torsion
Insufficient cervical dilation
Foetal malpresentation/abnormal calf/dead or emphysematous calf (where foetotomy not feasible)
Constricted vagina and vestibulum (where massage has not relieved constriction)
35
Why should you avoid sedation when performing a caesarian on a cow?
Can (eg xylazine) cross placental barrier and thus affect calf and decrease viability
36
Which anaesthesia techniques should be used when doing a bovine epidural?
```
Caudal epidural (to block Ferguson's reflex)
Paravertebral nerve block
```
37
What is Ferguson's reflex?
Reflex comprising the self-sustaining cycle of uterine contractions initiated by pressure at the cervix or vaginal walls
Positive feedback
38
Which pre-op medication should be given before a bovine caesarian?
Clenbuterol
NSAID
Antibiotic
Calcium where appropriate
39
Where would you incise when performing a left flank bovine caesarian?
1 hands breadth below transverse processes to 1 hands breadth behind last rib (approximately the length from fingertip to elbow)
40
Briefly describe a left flank bovine caesarian
Make vertical incision
Locate uterine horn containing calf and exteriorise
Incise uterus (from hock to toe/carpus to toe if breech)
Remove calf
Suture uterus- 2 layers (inverted suture pattern, bury knots)
Clean off contamination from uterus, rumen, remove blood clots from abdomen
Suture body wall and skin (add antibiotics to muscle layers) ('tack' layers together to eliminate dead space)
Post-op medication: oxytocin, calcium if appropriate
41
Which method can you use to cast a cow?
Reuff's method (uses ropes to bring a cow down to one side)
42
What is an emphysematous calf?
Dead calf filled with air as they are decomposing
43
Which sedation would you give to a cow when removing an emphysemetous calf?
Xylazine with ketamine
44
Where would you incise when performing a caesarian to remove an emphysematous calf?
Between left stifle and point of entry of the milk vein into the abdomen (40-50cm long)
45
What are some complications of a bovine caesarian?
Haemorrhage (cow may be off colour, tachycardic; re-open and ligate bleed)
Peritonitis (cow may be pyrexic; re-open, identify any leakage, flush abdomen with sterile saline)
Localised adhesions (ovarian, uterine)
Retained foetal membranes
Metritis
Wound infection/seroma/breakdown/emphysema
46
Why may a cow have a uterine prolapse?
Hypocalcaemia
47
What causes milk fever in cows?
Hypocalcaemia
48
How do you replace a uterine prolapse in a cow?
Cow should be standing or in sternal recumbency with HLs out behind her
1. Caudal epidural anaesthesia +/- clenbuterol
2. Put protective cover under uterus
3. Remove foetal membranes and clean off contamination
4. Apply lubricant and gradually feed uterus back in (don't use fingertips -> rupture uterus)
5. Once replaced, ensure horn tips fully everted by using a bottle to extend the reach of your arm, or fill uterus with water
6. Give oxytocin, NSAIDs, antibiotics, calcium
49
When during a cow's life does she start to make profit?
3rd pregnancy
50
How old is a cow when she has her first service and calf?
| What should her weight be at service?
Service: 13-14 months (>380kg)
Calf: 24 months
51
How much should a calf weigh at weaning and 3 months old?
Weaning: >65kg
| 3 months old: >120kg
52
How much should a cow grow per day in order to be 400kg at first service?
40kg at birth
Should be served at 400 days old
Therefore needs to grow 360kg in 400 days = 0.9kg/day
53
Which factors may put a constraint on calf growth?
Disease (neonatal calf scours, 5-21 days old) (pneumonia) (6-12 weeks old)
Sub-optimal nutrition (most rapid growth occurs in early life; lack of colostrum)
Sub-optimal environment (dirty -> bacteria)
54
How much milk should a calf be fed?
2x2x2
2 litres each feed, twice a day, 2 month weaning
55
What is the daily growth rate of a dairy calf?
1kg/day
56
What is the maximum group size for housing calves?
| Within what age range?
8 calves maximum, within a 14 day age range
57
Compare single penned to group housing for calves
```
Single penned:
Reduced risk of disease
Less social
More labour
Less growth
```
```
Group housing:
Better growth
Social interactions
Increased risk of disease
Less labour
```
58
What is the lower critical temperature of a calf?
| What happens below this?
15-20 degrees
Calf uses energy to keep warm -> less energy for growth (poor growth)
-> less energy for immune responses (more disease, poor growth)
59
```
What % extra of milk replacer should you feed to a calf when it is cold?
15 degrees
10 degrees
5 degrees
0 degrees
```
15 degrees: +15%
10 degrees: +27%
5 degrees: +40%
0 degrees: +50%
60
Adding dry straw for 'nesting' adds how much to a calf's body temperature?
4 degrees
61
What are the criteria for weaning a calf?
At least 8 weeks old
| When calf is eating at least 1.5kg daily and weighs at least 65kg
62
How much metabolisable energy does a calf need at weaning?
| What does it typically eat?
11 MJ/kg
| Lots of cake, relatively small forage intake
63
How much metabolisable energy does a calf need at puberty?
| What does it typically eat?
9MJ/kg
ME falls as calf consumes more forage
Give forage ad lib
Hay/straw
64
What % crude protein (CP) should a calf be eating from weaning to service?
15%
65
What is the DMI (dry matter intake) of a cow between weaning and calving?
Weaning: 3%
Calving: 2%
66
How can we feed more milk replacer to calves?
Increase milk replacer concentration eg up to 15%
Increase volume fed eg 3.5l/feed
Feed 3x daily
Computerised feeders (shared teat is a risk factor for pneumonia)
Ad lib feeding (acidified cold milk)
67
How can you monitor calf growth?
Weight
| Withers height
68
What should the withers height of a cow be for service?
>125cm
69
The kennel club will not register litters born to bitches under which circumstances?
Bitches over 8 years of age
| Bitches that have had 6 or more litters
70
When should a bitch be spayed?
6 months of age to prevent mammary tumours
Spaying after 2-3 years shows no reduction in likelihood of mammary tumours
In anoestrus (3 months after season) so as not to develop a pseudo-pregnancy
71
When does puberty occur in bitches?
As early as 6 months and as late as 20 months
| Smaller breeds tend to come into season earlier than giant breeds
72
When are bitches generally first mated?
Second or third season
73
How long does pro-oestrus last in the dog?
9 days
74
How often does a bitch have a season?
Every 6 months, however some have 4 or 12-month intervals
| GSDs and Rotties can come into season every 3 months
75
What are the signs that a bitch is in pro-oestrus?
Vulva swells and reddens
Serosanguinous discharge from vagina
Will not stand to be mated
76
When does ovulation occur in the bitch?
Towards the end of pro-oestrus and the beginning of oestrus (around day 9)
77
How long does oestrus last in the bitch?
9 days
| Starts when bitch stands to be mated and ends when she refuses
78
In dogs, when are ova ready to be fertilised?
Up to 48 hours after being released (around day 11)
Need to undergo meiotic division
Are then fertile for 3 days
79
In dogs, how long can spermatozoa survive in the bitches genital tract?
7-10 days, as they attach to the endometrium
80
What is metoestrus?
How long does it last in the dog?
What are the clinical signs?
Starts when the bitch first refuses to stand
Lasts about 60 days
Vulva becomes less swollen, bloody discharge gradually ceases, may be a mucoid discharge
High progesterone levels
False pregnancies and pyometra occur during metoestrus
81
What is Anoestrus?
| How long does it last in the dog?
Period between seasons, very little ovarian activity
| Usually lasts 4 months
82
Where is GnRH released from?
| What does it stand for?
Gonadotrophin-releasing hormone
Released from hypothalamus (after puberty) in a pulsatile manner and causes the anterior pituitary gland to release FSH and LH
83
How does medical neutering work?
Deslorelin, GnRH agonist
Initially causes stimulation but then causes inactivity of gonadotrophin-producing cells because pulsatile stimuli are prevented
Known as down-regulation
84
What is the role of FSH in males and females?
Females: stimulates growth of follicles in the ovaries
Males: binds to Sertoli cells and spermatogonia (early sperm cells) regulating spermatogenesis
85
What is the role of LH in males and females?
Females: stimulates the maturation, luteinisation and ovulation of ovarian follicles. Ovulation occurs 30-48 hours after LH peak. Maintains the function of the corpus luteum
Males: binds to Leydig cells and regulates testosterone production
86
When are oestrogen levels raised?
Pro-oestrus
87
What is oestrogen produced by?
Growing follicles
88
What is progesterone produced by?
Mature follicles and corpus luteum
| Maintains pregnancy
89
Where is prolactin produced and what does it do?
Secreted by anterior pituitary gland
Maintains function of corpus luteum and maintains a high progesterone concentration
Stimulates milk production
Causes signs of pseudo-pregnancy
90
Which is the only known pregnancy-specific hormone in the bitch?
What is it produced by?
What does it do?
Relaxin
Produced by placenta
Causes the pelvic ligaments to relax during parturition
Used to diagnose pregnancy in the bitch
91
Which hormone is used to diagnose pregnancy in the bitch?
Relaxin
92
What is the role of prostaglandins in the pregnant bitch?
Cause the final lysis of the corpus luteum and the initiation of parturition
Canine CL is quite resistant to prostaglandins, and need a number of injections to cause lysis (abortion) (twice daily for 4 days or more)
93
Where is oxytocin produced?
| What does it do?
Within supra-optic nucleus (in hypothalamus) and is transported axonally to storage sites in posterior pituitary
Causes milk let dos and uterine contractions
94
```
What would you see on a vaginal cytology smear from a bitch during:
Pro-oestrus
Oestrus
Metoestrus
Anoestrus
```
Pro-oestrus: parabasal, small intermediate and large intermediate epithelial cells. Few WBCs. Many RBCs and bacteria. Towards the end of pro-oestrus there are anuclear or cornified cells (cornflakes)
Oestrus: early= maximal cornification, between 60-90% of cells are straight-sided with small/no nucleus. No WBCs, variable RBCs. ,ay be bacteria
Metoestrus: parabasal and small intermediate cells. Polymorphonuclear leukocytes. No RBCs or bacteria.
Anoestrus: parabasal and small intermediate cells. Few WBCs. No RBCs or bacteria
95
What should the blood progesterone level of a bitch be for her to be mated?
>8ng/ml for AI or if can only do one mating
| 4ng/ml for natural matings then again 2 days later
96
How long is gestation in a dog?
58-71 days
97
When should you worm puppies?
2 and 5 weeks old with Panacur liquid
98
How can you detect pregnancy in a bitch?
Behavioural changes: reduced appetite 3-4 weeks after mating, then increase in appetite by 50% after day 40
Physical changes: pink and erect teats with mammary gland enlargement from day 40. Abdomen swells from day 40
Abdominal palpation: done at 4 weeks ('ping pong balls')
Foetal heart beats in late pregnancy (twice that of bitch)
Radiography: after 7 weeks as foetal bones are mineralised
Blood tests: relaxin from day 24
Ultrasound: scan from 28 days, can be scanned again at 7 weeks in case of resorption
99
A rectal temperature of what indicates that a bitch will whelp soon?
Within how long?
What about blood progesterone?
Below 37 degrees means she will start within 8-24 hours
| Progesterone: a fall between 5-8ng/ml means parturition will start within 14 hours
100
How may a bitch appear a few days before parturition?
Restless, seek seclusion or be excessively attentive, may refuse all food
May show nesting behaviour 12-24 hours before parturition
101
Describe the first stage of labour in a bitch
Vagina relaxes and cervix dilates
Normally lasts for 6-12 hours
Panting, tearing up/rearranging bedding, shivering, looking at flanks, may vomit
102
Describe the second stage of labour in a bitch
Puppies are born
Lasts 3-12 hours
3 signs that the bitch has entered second stage: first water bag bursts, visible abdominal straining, rectal temp returns to normal
First foetus is usually delivered within 4 hours of onset of second stage. Bitch normally breaks membrane, licks pup and severs umbilical cord
103
Describe the third stage of labour in a bitch
Expulsion of placenta
Usually follows within 15 mins of the delivery of each pup, although 2 or 3 pups may be born before the passage of their placentas
Remove placentas as may cause v/d if bitch eats them
Greenish discharge is normal following whelping and is the expulsion of foetal fluids and placental remains, can last for 3 weeks
104
When should you intervene during whelping?
Strong frequent straining but no pup for 50 minutes
Greenish/red-brown discharge but no pup within 2-4 hours
Fetal fluid was passed more than 2-3 hours ago but no pups
Weak irregular straining for over 2 hours
Been in second stage labour for over 12 hours
105
Why might III need to examine a bitch after whelping?
```
If not all placentas have been passed within 4-6 hours
Putrid/foul-smelling discharge
Continual heavy vaginal bleeding
Puppies are dull or won't suckle
Bitch is pyrexic or dull
```
106
What should the interval between births of puppies be?
5-120 minutes
107
Give some causes of Dystocia in the dog
Uterine inertia
Obstruction of the birth canal (eg narrow pelvic canal, neoplasms, uterine rupture, vaginal fibrosis)
Malpresentation of puppy
108
Why might you perform a Caesarian in a bitch?
Primary uterine inertia (if P4
109
What is the difference between primary and secondary uterine inertia?
Primary: uterus fails to contract (eg when there are only 1 or 2 pups) because there is insufficient stimulation to initiate labour, or because of over stretching of the myometrium in large litters
Secondary: parturition has started but stops due to exhaustion of the myometrium caused by obstruction of the birth canal
110
What should you give a bitch an hour before caesarian and why?
Dexamethasone 0.5-1ml/10kg IV
| Increases surfactant in pups lungs
111
Describe a possible procedure for administering GA to a bitch undergoing caesarian
Pre-med normally recommended (reduce stress and anxiety)
Induce with Propofol (short duration of action)
Put on IV fluids (Lactated ringers, 10-20ml/kg/hour)
Maintain with isofluorane and oxygen
Give carprofen once pups are out
Post-op oxytocin hastens uterine involution and evacuation of fluids (unless bitch has been spayed)
Send home with synulox and carprofen tablets
112
Which approach is preferred for bitch caesarian and why?
Midline as it provides better access to uterus, bitch can lie comfortably on both sides and pups don't interfere with the wound
113
Briefly describe a bitch Caesarian
Dorsal midline approach
Incise linea alba (careful as gravid uterus is underneath)
Exteriorise uterus with wet swabs
Large litters: make incision in middle of each uterine horn
Small litters: make incision in uterine body
Incise between placentas
Remove pups in uterine body first, then grasp foetus and gently rupture amniotic sac to allow removal of foetus
Clamp umbilical cord 1-2cm from foetal abdominal wall and remove placenta (firmly attached placentas can be left in situ)
114
How do you close the uterus after a bitch Caesarian?
Continuous inverting suture pattern (eg Lembert) to invert the myometrium and appose the serosa
Use Vicryl
115
Why might a bitch not produce milk after a caesarian?
Lain
Anxiety
Parturition was not imminent
116
Give some causes of abortion in dogs
Brucella canis
CDV (canine distemper virus)
CHV (canine herpes virus)
Toxoplasma gondii
117
Give some post-parturient conditions in the bitch
Uterine prolapse/rupture
Toxic milk syndrome (toxins excreted into milk causing ill pups-hand rear)
Subinvolution of placental sites (don't get smaller)
Acute metritis
Retained placenta/foetuses
Haemorrhage
Hypocalcaemia (Ca loss in milk)
Agalactia (failure of milk let-down)
Galactostasis (milk stasis affecting last 2 caudal glands)
Acute mastitis
Mammary tumours
118
Give some clinical signs of preudopregnancy in the bitch
Anorexia, nest making, nursing of inanimate objects, lactation that may lead to mastitis and aggression
Last 2 mammary glands swollen
119
What is the treatment of choice for pseudopregnancy in the bitch?
Cabergoline (Galastop) 5mcg/kg/day, can give every other day after 10 days
(Prolactin antagonist)
May require diuretics or sedatives
Can also spay
Don't give any treatment if just cloudy vulval discharge
120
How does pyometra occur?
| How does it lead to death?
Progesterone induced endometrial hyperplasia -> cystic endometrial hyperplasia -> pyometra
Secondary bacterial infection (usually E.Coli) -> endotoxaemia -> PU/PD, lethargy, anorexia, D/V, collapse and death
121
What can you give to cause abortion in the bitch?
'Estrumate' (prostaglandin, Cloprostenol) 5mcg/kg every other day for 10 days use with Cabergoline 5mcg/kg/day for 10 days
Start at day 28 and pups will be reabsorbed with no vaginal discharge
122
How do you induce oestrus in the bitch?
Cabergoline 5mcg/kg/day
| Use in late anoestrus
123
What is silent oestrus?
| What dog breed is it seen in?
Bitch ovulated during a normal season but there are no external signs of proestrus or oestrus
Greyhounds
