14 to 21 Day Post-Service Vulval Discharge

Definition	Infection of uterus during breeding, which is released at the next oestrus
Clinical signs	Sows with a creamy cheesy discharge from the vulva which subsequently repeat
Causal agent	None specifically identified. Escherichia coli (E. coli), staphylococcus, streptococcus and klebsiella are often isolated from swabs
Management factors	Infection of the genital tract late in oestrus
Treatment
Individual
1	If the sow returns to oestrus 18 to 21 days post-service, cull the sow
2	No antimicrobial therapy will be effective at stopping discharge or maintaining 'pregnancy'
Herd
Breeding control
	Two services only are needed 24 hours apart am/am ideally
	Only serve sows in standing heat, recognised the signs of oestrus. Late serving is strongly associated with 14-21 day vulval discharges
	Use all AI or Use single natural service followed by AI
Breeding area hygiene
	At all times stalled sows must be separated from her urine and faeces
	Clean any sow with a soiled rear prior to service. Ideally this should be done on arrival to service area
	Avoid human contact with the boar's penis during service, only use prepuce to direct penis
	Ensure that the underline of the boar is kept clean by managing the boar in a clean dry environment
	Ensure service is carried out on a good non slip floor
	Do not serve lame sows with boars, only use AI
	Cease heat checking by 'thumbing'
	Ensure AI service carried out by single use disposable catheters
Farrowing house management
To limit trauma and infection of the vagina and bladder
	Improve hygiene behind the sow by manually removing faeces 3 days prior and 7 days post-farrowing. Very dirty rear regions should be cleaned with soap and water
	Reduce manual farrowing as much as possible, use plastic gloves and clean hands
	All sows manually farrowed should receive a suitable antibiotic by 16 g 1.5" needle intramuscularly into the neck
	Encourage the correct use of oxytocin at 5 IU doses
	Ideally increase lactating length to 24 days
Increase water supplies to flush out vagina
	Heat check three times daily in breeding area and ensure sows rise and urinate
	Ensure water supplies clean and freely available
Antibiotic therapy
	Consult your veterinarian

The pathogenesis of 14-21 post-service vulval discharges:

Normal events in good standing heat
12 x 10^10 sperm and normal bacteria in 150 ml enters the uterus. Protective oestrogen levels are high		Uterine contractions rapidly transport semen to oviducts. 100,000 sperm only enter oviduct		The uterine defence mechanisms kill off any sperm remaining in the uterus and any bacteria		After ovulation uterine defence mechanism switches off. Progesterone rises. Cervix closes			Day 2-3 embryos enter the uterus. Pregnancy continues. Embroys implant in insensitive uterus
Serving late
Sow possibly still in some standing heat, may need some force. 12 x 10^10 sperm in 150 ml with normal bacteria enters the uterus.	Uterine defence mechanism reduced under increased progesterone levels.		Uterine contractions poor with poor uptake of semen		Uterine defence mechanism not activated to kill off sperm or invading bacteria.		Cervix closes trapping the invading bacteria. Bacteria multiply and uterus responses with normal immune response.			Day 2-3 post ovulation embryos enter uterus fighting bacteria embryos caught in battle and die. Go to new line.
Infection killed. Purulent material trapped by closed cervix.	No positive pregnancy signals. Sow prepares to return on days 18-24		Day 14 to 21 cervix opens and purulent material is released. Healed uterus looks normal					Sows with a purulent post-service vulval discharge evident between 14 and 21 days post-service. Both sows presented in oestrus within 4 days of the discharge becoming evident