Lecture Notes on Veterinary
Obstetrics, VCT 601 (PPT)
BY
S.’Tona Olurode,DVM,MVSc.(Theriogenology)
COLVET, UNAAB
BOVINE PREGNANCY AND
ITS DIAGNOSIS
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Indication for Bovine Px Dx:
to detect those non-pregnant so
that appropriate measure(s) can be
taken.
NB:
Age at 1st calving is approx 24mos
for dairy cows and subsequently at
13-13.5mos intervals
After ~60days post insem foetal
death rates are low
Pregnancy diagnosis
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Methods used grouped under the
following subheadings:
Management
Chemical or laboratory method
Clinical examination
Ultrasonography
Managemental methods of
px dx
• Non-return to oestrus and CL
persistence
• History of exposure of cow to a bull or
A.I.
• Mammary gld devpt (useful only in
primigravida)
• Abdominal ballottment possible at
~7mos of gestation in small breeds such
as jersey
Chemical or Laboratory
methods
• EPF/ECF demonstration in serum or milk
via commercial test kits using the ‘dip
stick’ principle; early in 3days or later in 78 days
• Progesterone assay in plasma & milk using
RIA or ELISA. Blood sample collected
21days post previous oestrus.
• Assay of px-specific protein B via RIA
good tool for twins identification
• Oestrone SO4 in milk
Clinical methods
• Transrectal palpation, can be done as
early as 30days in heifers and 35days
in cows.
(disadvantages – much practice is
reqd)
-uterine assymmetry
-membrane/foetal slip
(see table 1 for the ‘rule of thumb’)
Table 1: Calf foetal size at various stages of pregnancy in relation to the size of some commonly known adult animals.
Stage of pregnancy
Calf foetal size in relation to the size of commonly known adult animals
2 months
Mouse
3 months
Rat
4 months
Small cat
5 months
Large cat
6 months
Beagle dog
position/diameter and
structures during
pregnancy
Stages of Pregnancy
(days of gestation)
Uterine position
Uterine diameter
Palpable structures
35-40
Pelvic floor
Slightly enlarged
Uterine asymmetry/foetal slip
45-50
Pelvic floor
5.0-6.5cm
Uterine asymmetry/foetal slip
60
Pelvis/abdomen
6.5-7.0cm
Membrane slip
90
Abdomen
8.0-10.0cm
Small placentomes/foetus
(10-15cm long)
120
Abdomen
12cm
Placentomes/foetus
(25-30cm long)/fremitus
150
Abdomen
18cm
Placentomes/foetus
(35-40cm long)/fremitus
Clinical methods contd’
• Vaginal examination using either of
the following ways:
• visually with the aid of vaginoscope
• manually through pressing the finger
directly on the external os of the
cervix to detect the presence of an
adhesive tenacious secretion
Ultrasonography
• Requires ultrasonic foetal pulse detector that
employs the Doppler principle. 2 types are available;
• ultrasonic depth analysers (A-mode) with disadv of
questionable degree of accuracy as early as 40days
• Realtime B-mode method of choice for early px dx in
the cow via transrectal imaging
• For early pxs 7.5MHz linear transducer is reqd while
late pxs prefers 3.5MHz transducers
• Useful in foetal age estimation (assmt of trunk
diameter) up to 140days,CRL not easy to assess; sex
determination via migration of genital tuberclein male, migration is towards the umbilicus whereas in
the female, it is towards the tail
Normal Birth in the cow
(Eutocia)
• Normal birth process= calving
• GL averages 290 days, sequel to series of
events emanating from the initiation of
parturition
Preparatory changes are those associated
with the udder, vulva and pelvic ligaments,
body Tº drops 24-48hrs b4 calving,
exudation of clear vaginal mucus,tail head
might appear raised with gluteal muscles
sunken
LABOUR
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Stage 1 of labour
Slide 5 of 56
Stage 2 of labour
Slide 7 of 56
Stage 3 of labour
Events of the 3 stages of
labour
• 1st stage – cervical dilatation or dilation,
the duration is about 3-8 hours in cows but
longer in heifers, 24hrs. The cardinal sign
is restlessness
• 2nd stage – foetal delivery, the duration
averages 2-4 hours in pluriparous cows but
longer in heifers, involves straining by the
dam
• 3rd stage - placental expulsion, time reqd
averages 8 hrs but can last 12hrs
sometimes which is still considered normal.
DYSTOCIA
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Causes of Dystocia
For convenience, causes are divided into 2:
1.
Maternalprimary uterine inertia- ocassioned by multiple or abnormal
foetuses which overstretch the uterus, a defect in the
myometrium that renders contraction impossible, hormonal
defect and periparturient hypocalcaemia. Dam may exhibit few
weak abdominal contractions that fail to progress to 2nd stage.
On exam.,cervix is found dilated with no foetus in the birth
canal. Treatment via gentle traction and correction of position
and postural defects.
secondary uterine inertia – consequent upon myometrial
exhaustion. Possible sequelae include retained placenta, delayed
uterine involution and uterine prolapse. Treatment is by removal
of the impediment.
abnormalities of the birth canal-inadequate pelvis, pelvic
exostoses, incomplete cervical dilatation, vaginal cystocoele,
neoplasms of the vulva and vagina, remnants of mullerian ducts
persisting, uterine torsion, stenosis of the vulva and vagina
(heritable in some breeds or due to immaturity.
2. Foetal
i. Abnormal foetal presentation,
position and posture
ii. Foetal monstrosities- Schistosoma
reflexus, perosomus elumbus e.t.c.
iii. Foetal oversize – most common
cause in cattle due to foetopelvic
disproportion
Obstetrical Procedures
Divided into 4 main groups viz.
1. Mutation- includes repulsion, rotation,
eversion, extension or adjustment of the
extremities. Useful to return a foetus to
normal P. P& P.
2. Forced traction
3. Embryotomy
4. Caesarian section
Lambing & Kidding
• GL ~ 140-150 days on the av.140 days for
sheep
• Prior to EDD, ewe shd be put on
observation every 4-6 hours to check for
certain conditions like pregnancy toxaemia,
hypocalcaemia, vaginal prolapse, abortion,
mastitis & rupture of the prepubic tendon.
Stages of parturition – consult the note!
Causes & Mgt. of dystocia
in sheep and goat
• Goat – parturition normally uneventful. If
labour extends beyond 30 mins, consider
dystocia.
• Most common forms arise when more than
one kids attempt to exit the birth canal at
the same time. Other causes are deviation
from normal PPP, foetomaternal
disproportion, failure of cervical dilatation
(ring womb), vaginal prolapse, uterine
torsion and uterine inertia.
Causes & Mgt. of dystocia
in sheep and goat cont’d
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Mgt – dx based on failure of active labour to be
initiated and history.
NB: if no delivery accomplished within 2-3 hrs,
the cervix will start to close.
Protocols of mgt requires:
Strict adherence to general principles of
cleanliness, lubrication and gentleness
Use of appropriate restraint techniques
± epidural anaesthesia
Relief of dystocia
Infectious causes of
abortion
• Goats tend to have high incidence of
abortion when compared to other livestock
species.
• Infectious causes of abortion is highly
significant. However, all or none principle
is assumed during an abortion outbreak i.e.
all causes of abortion are infectious in
nature
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Infectious causes of abortion, therefore, include the
following:
Chlamydiosis
Toxoplasmosis
Q-fever
Listeriosis
Leptospirosis
Mycoplasmosis
Campylobacteriosis
Brucellosis
Salmonellosis
Yersiniosis
Trypanosomosis
Sarcocystosis
anaplasmosis
Non-Infectious causes of
abortion
• Early embryonic death- due to several physiologic
or environmental factors sequel to predisposing
factors e.g. stress, nutrition etc.
• Genetic disorders- habitual abortion may be
heritable or cross resulting in abnormal
chromosomes
• Nutritional factors- deficient E & protein in the
diet most esp in the late gestation
• Toxic plants and pharmaceuticals
POST-PARTUM
DISEASES
• Uterine prolapse
• Vaginal prolapse
• Acute septic metritis (puerperal
metritis)
• Mastitis
• Retained placenta
Foetotomy (Embryotomy)
• Term used to describe method of dividing
the foetus into smaller pieces to ensure
easy passage thro’ the birth canal.
• Commonly employed in cattle, occasional in
horses, rarely in sheep & goat and almost
never in pigs and small animals. The
technique is a method of choice esp when
foetus is ascertained to be dead in utero.
Classification of
Foetotomy
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2 classes basically, viz;
Complete/ Total
Incomplete / Partial
2 techniques available
Percutaneous foetotomy
Subcutaneous foetotomy
Percutaneous foetotomy
• Requires a tubular embryotome which
confers protection on the maternal
tissues against damage while sawing
through the dead foetus
• Preferred method for nondecomposed foetuses
Subcutaneous foetotomy
• Involves dissecting out foetal parts
from within its skin to cause
reduction in foetal bulk and allowing
the delivery of the remainder mass
par vaginum.
Indications for complete
foetotomy
• Relief of dystocia caused by foetal maldisposition
• Relief of dystocia caused by foetopelvic
disproportion (foetal oversize, foetal monsters)
• Relief of dystocia caused by engaged foetus
within the birth canal e.g. stifle lock (hip lock)
• During CS when large or deformed or maldisposed
foetus is encountered
Indications for partial
foetotomy
• Deviation of the head
• Shoulder flexion
• Breech presentation (bilateral hip
flexion)
• Posterior presentation (hock flexion)
• Foetal monsters
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Care of the dam following
foetotomy include :
Manual exam of vagina and uterus
Administration of local and
parenteral antibiotics
Non-steroidal anti-inflammatory
therapy
Careful removal of the placenta
from the caruncles
Careful nursing
Thanks for your attention