Post on 09-Apr-2017
Normal parturition process in large animals
(bovine and equine)M.Waseem
DVM, UCV&As, IUB
Why to study
normal process?
To understand the time of
calving
To assistance in calving
To understand
the dystocia
Parturition
Give birth to young one
Possible factors that induces parturition
Increases in fetal size
Fatty degeneration of placenta
Physiological factors Increased co2
in maternal blood due to fetal activity
Release of fetal antigen serotonin
Biochemical factors
ParturitionPhysiological factors
Biochemical factorsHypothalamus Anterior
PituitaryAdrenal Cortex
CRH ACTH
Fetal Corticosteroids(Cortisol)
Lung(surfactant)
Liver(glycogen)
Thyroid(metabolism)
Progesterone Estrogen PGF2a
UterineContractions
Relaxin
Oxytocin
Uterine Endometrium» Oxytocin receptors
Ovary(CL)
CLRegression
Pelvic ligament stretching
placenta
enzymes
17-alpha hydroxylase
aromatase17-20 dismolase
Enzymes converting P4 to E2
Final Role of OxytocinSensory Neurons in Cervix
Oxytocin fromPosterior Pituitary
MyometrialContractions
Signs of labor
changes in body temperature
enlargement of the vulva
relaxation of the sacro-sciatic
ligaments
dilation of the cervix.
changes in quantity and viscosity of vaginal
secretions
udder changes including enlargement, tenseness and filling of the teats
Process of parturition consists of 3 stages
stages
Stage 1: Cervical dilation
Stage 3: Expulsion of the placenta
Stage 2: Delivery of the fetus
Stage 1 signs
The pastured cow will usually seek an isolated
place.
Restlessness ,lie down and get up
frequently
Occasionally, she will kick at her belly and wring her tail.
The cow (particularly first-calf heifers) will
show signs of uneasiness and
pain.
Vaginal discharges increase
Stage 2 signs
cervix is fully dilated.
plus fetal parts enter the birth canal
second water sac (amniotic sac)
Normalp.p.p
presentation
position
posture
Anterior longitudinal
Dorsal or dorsosacral
extended
Expulsion of fetal
membranes
3rd stage