Changes

* Timing may not be absolutely perfect, there is considerable variation in the timing of drug action and effect.

* Timing may not be absolutely perfect, there is considerable variation in the timing of drug action and effect.

* Premature delivery of small, immature offspring.

* Premature delivery of small, immature offspring.

* Increased incidence of [[Parturition_-_Risks_in_Parturition_-_Anatomy_%26_Physiology#Retained_Placenta|retained placenta]].

* Increased incidence of [[Parturition_-_Risks_in_Parturition_- Anatomy & Physiology#Retained_Placenta|retained placenta]].

* Pharmacological induction can only be used commercially in cattle and pigs.  Induction in other species is used only to overcome birth associated problems.

* Pharmacological induction can only be used commercially in cattle and pigs.  Induction in other species is used only to overcome birth associated problems.

* Increased dystocia in cattle

* Increased dystocia in cattle

You must ensure the foetus is appropriately developed before inducing parturition.  The lungs must be mature to enable survival.  Naturally maturation of the lungs is induced by foetal cortisol, so it may be useful to administer '''glucocorticoids''' to artificially mature the lungs.

You must ensure the foetus is appropriately developed before inducing parturition.  The lungs must be mature to enable survival.  Naturally maturation of the lungs is induced by foetal cortisol, so it may be useful to administer '''glucocorticoids''' to artificially mature the lungs.

   Prostaglandin F2α: [[Parturition_-_Cervical_Softening_-_Anatomy_%26_Physiology|Cervical dilation]]

   Prostaglandin F2α: [[Parturition_-_Cervical_Softening_- Anatomy & Physiology|Cervical dilation]]

   Prostaglandin F2α and Oxytocin: [[Parturition_-_Coordinated_Myometrial_Contraction_-_Anatomy_%26_Physiology|Uterine contractions]]

   Prostaglandin F2α and Oxytocin: [[Parturition_-_Coordinated_Myometrial_Contraction_- Anatomy & Physiology|Uterine contractions]]

   Oxytocin: delivery of the [[Gestation_-Placenta_-_Anatomy_%26_Physiology|Placenta]]

   Oxytocin: delivery of the [[Gestation_-Placenta_- Anatomy & Physiology|Placenta]]

* Oxytocin and Prostaglandin F2α both signal by the Gαq -> IP3 + DAG pathway to raise intracellular calcium , so are able to effect each other in the [[Parturition_-_Endocrine_Control_of_Parturition_-_Anatomy_%26_Physiology#Furgesson_Reflex|Fergusson reflex]].

* Oxytocin and Prostaglandin F2α both signal by the Gαq -> IP3 + DAG pathway to raise intracellular calcium , so are able to effect each other in the [[Parturition_-_Endocrine_Control_of_Parturition_- Anatomy & Physiology#Furgesson_Reflex|Fergusson reflex]].

* COX II increases during labour, so prostaglandins will form as long as arachidonic acid is available.

* COX II increases during labour, so prostaglandins will form as long as arachidonic acid is available.

* Used in conjuction with Oestradiol Benzoate

* Used in conjuction with Oestradiol Benzoate

** Oestradiol induces oxytocin receoptor upregulation on the endometrium.   

** Oestradiol induces oxytocin receoptor upregulation on the endometrium.   

** Inhibits uterine activity, but sensitizes the [[Female_Reproductive_Tract_-The_Uterus_-_Anatomy_%26_Physiology|uterus]] to oxytocin.

** Inhibits uterine activity, but sensitizes the [[Female_Reproductive_Tract_-The_Uterus_- Anatomy & Physiology|uterus]] to oxytocin.

=== Tocolytic Drugs ===

=== Tocolytic Drugs ===

== Myometrial Innervation and Manipulation ==

== Myometrial Innervation and Manipulation ==

The autonomic nervous system is not important in normal labour, since uterine contractions are controlled by the [[Pituitary_Gland_-_Anatomy_%26_Physiology#Parturition|neuroendocrine release of oxytocin]]. However, the autonomic nervous system can be used to control parturition pharmacologically by changing cAMP levels which effects the myometrium.

The autonomic nervous system is not important in normal labour, since uterine contractions are controlled by the [[Pituitary_Gland_- Anatomy & Physiology#Parturition|neuroendocrine release of oxytocin]]. However, the autonomic nervous system can be used to control parturition pharmacologically by changing cAMP levels which effects the myometrium.

=== Sympathetic ===

=== Sympathetic ===

===== Corticosteroids =====

===== Corticosteroids =====

* Mimic foetal cortisol to remove the progesterone block by upregulating enzymes that will increase the oestrogen:progesterone ratio (for more information see [[Parturition_-_Endocrine_Control_of_Parturition_-_Anatomy_%26_Physiology|endocrinology of parturition]]).

* Mimic foetal cortisol to remove the progesterone block by upregulating enzymes that will increase the oestrogen:progesterone ratio (for more information see [[Parturition_-_Endocrine_Control_of_Parturition_- Anatomy & Physiology|endocrinology of parturition]]).

* '''Short Acting''': apply 2-3 days before the due date (270+ days gestation).  Complications include [[Parturition_-_Risks_in_Parturition_-_Anatomy_%26_Physiology#Retained_Placenta|retained placenta]] and stillbirth.

* '''Short Acting''': apply 2-3 days before the due date (270+ days gestation).  Complications include [[Parturition_-_Risks_in_Parturition_- Anatomy & Physiology#Retained_Placenta|retained placenta]] and stillbirth.

* '''Medium-Long Acting''': apply 2-3 weeks before the due date.  Administration after 260 days will cause no advance of the calving date. Administration before 260 days will cause neonatal mortality.  Thus use of these corticosteroids is reliant upon accurate record keeping by the farmer so that exact dates are known.

* '''Medium-Long Acting''': apply 2-3 weeks before the due date.  Administration after 260 days will cause no advance of the calving date. Administration before 260 days will cause neonatal mortality.  Thus use of these corticosteroids is reliant upon accurate record keeping by the farmer so that exact dates are known.

===== Corticosteroid & PGF2α  Analogue =====

===== Corticosteroid & PGF2α  Analogue =====

* Has the additional benefit of acting to [[Parturition_-_Cervical_Softening_-_Anatomy_%26_Physiology|dilate and soften the cervix]] to facillitate delivery.

* Has the additional benefit of acting to [[Parturition_-_Cervical_Softening_- Anatomy & Physiology|dilate and soften the cervix]] to facillitate delivery.

===== PGF2α Analogue Alone =====

===== PGF2α Analogue Alone =====

* Administer 2 days before the mean [[Reproductive System - Anatomy & Physiology#Gestation|gestation]] of the herd.

* Administer 2 days before the mean [[Reproductive System - Anatomy & Physiology#Gestation|gestation]] of the herd.

* Causes luteolysis to remove the progesterone block keeping the [[Female_Reproductive_Tract_-The_Uterus_-_Anatomy_%26_Physiology|uterus]] quiescent.

* Causes luteolysis to remove the progesterone block keeping the [[Female_Reproductive_Tract_-The_Uterus_- Anatomy & Physiology|uterus]] quiescent.

* 97% will farrow within 36 hours

* 97% will farrow within 36 hours

* Used to ensure tight farrowing

* Used to ensure tight farrowing

* Favoured method

* Favoured method

* Tightens the delivery pattern

* Tightens the delivery pattern

* The oxytocin increases milk production and ensures delivery of the [[Gestation_-Placenta_-_Anatomy_%26_Physiology|placenta]].

* The oxytocin increases milk production and ensures delivery of the [[Gestation_-Placenta_- Anatomy & Physiology|placenta]].

===== β Adrenergic Antagonist =====

===== β Adrenergic Antagonist =====

=== Mare ===

=== Mare ===

Drugs are used in individuals with a history of difficult birth and in emergency situations,  The mare must be 320-330 days pregnant to ensure adequate maturity of the foetus.  Also, the [[Lactation_-_The_Mammary_Gland_-_Anatomy_%26_Physiology|mammary gland]] must be developed and contain [[Lactation_-_Milk_Composition_and_Biosynthesis-_Anatomy_%26_Physiology#Colostrum|colostrum]].  The [[Lactation_-_The_Mammary_Gland_-_Anatomy_%26_Physiology|mammary gland]] is a good indicator of foetal maturity.  Mammary secretion of calcium carbonate increases 24 hours before foaling.  So, calcium carbonate levels can be used to assess foetal maturity prior to induction.  Mammary secretions are generally tested using a titret kit. A disadvantage of this is that essential immunoglobulins can be lost by this pre-parturient release of colostrum, resulting in the foal receiving less colostrum on its first suckle.

Drugs are used in individuals with a history of difficult birth and in emergency situations,  The mare must be 320-330 days pregnant to ensure adequate maturity of the foetus.  Also, the [[Lactation_-_The_Mammary_Gland_- Anatomy & Physiology|mammary gland]] must be developed and contain [[Lactation_-_Milk_Composition_and_Biosynthesis- Anatomy & Physiology#Colostrum|colostrum]].  The [[Lactation_-_The_Mammary_Gland_- Anatomy & Physiology|mammary gland]] is a good indicator of foetal maturity.  Mammary secretion of calcium carbonate increases 24 hours before foaling.  So, calcium carbonate levels can be used to assess foetal maturity prior to induction.  Mammary secretions are generally tested using a titret kit. A disadvantage of this is that essential immunoglobulins can be lost by this pre-parturient release of colostrum, resulting in the foal receiving less colostrum on its first suckle.

* Corticosteroids are NOT effective and prostaglandin results in abdominal pain.

* Corticosteroids are NOT effective and prostaglandin results in abdominal pain.