A Detailed Guide to Sow Farrowing Time and Key Feeding and Management Points
Farrowing specifically refers to the period and process in which the fetus leaves the mother's body and becomes an independent individual. Pigs, like humans, are viviparous, so when do sows generally farrow? What are the key feeding and management points?
When do sows generally farrow?
Sows mostly farrow at night, generally lying on their side; after several intense bouts of straining and abdominal pressing (abdominal pressing refers to the tonic contraction of the respiratory muscles: the abdominal wall muscles and the diaphragm, which push the fetus outward; it is a reflex contraction caused by the straining squeezing the fetus into the birth canal and pressing on the nerves of the birth canal), the fetal membranes rupture, blood water and amniotic fluid flow out, and then the piglets are delivered. In a normal farrowing, one piglet is usually delivered every 5 to 25 minutes; after all piglets are delivered, the fetal membranes are expelled 10-20 minutes later, and the whole farrowing process takes about 1 to 4 hours. To improve the survival rate of piglets, manual assistance during farrowing is mostly carried out for sows.
What are the key feeding and management points for sow farrowing?
1. Pre-farrowing preparation. Accurately calculate the expected farrowing date (the gestation period of pigs is 114 days), and prepare clean towels, silk thread, scissors, disinfectant, as well as a piglet farrowing box, heat preservation lamps and other farrowing supplies. The person assisting the farrowing should first disinfect their arms and the farrowing tools.
2. Farrowing assistance management. Keep watch in shifts day and night over sows about to farrow, ready to assist at any time. After a piglet is born, immediately wipe dry the mucus from its mouth, nose and whole body with a cloth so that the piglet can breathe freely, tie and cut the umbilical cord at about 3 cm from the piglet's abdomen, and disinfect the cut end with 2% iodine tincture. Also do a good job in rescuing apparently stillborn piglets, weighing, numbering, tooth clipping and tail docking.
3. Handling of difficult farrowing. If no piglet is delivered after 30 minutes of straining, assistance for difficult farrowing should be carried out. Drug-assisted farrowing: the dosage of oxytocin is 2 ml per 100 kg of body weight; after injection, piglets can be delivered in 20-30 minutes; if ineffective, manual assistance should be used. Manual assistance: the assistant should cut short and file smooth their fingernails, wash their hands with soapy water, then disinfect their hands and arms with disinfectant, apply lubricant or wear sterilized rubber gloves, then insert their hand into the sow's birth canal and pull out the piglet along with the rhythm of the sow's straining. After one piglet is pulled out, if delivery becomes normal, manual assistance is no longer needed. After the procedure, inject antibiotics into the sow to prevent infection.
4. Do a good job in feeding and management of sows before and after farrowing. Pay special attention to the condition of the sow 5-7 days before farrowing, and deal with any problems promptly to ensure normal digestive tract function in the sow and prevent constipation and elevated body temperature. On the day of farrowing, the sow can be fed 1-1.5 kg of daily ration, and fed 2-3 times with bran salt water soup (20 g bran, 25 g salt, 2 kg water). For 2-3 days after farrowing, the feeding amount should be 1/3 to 1/2 of the normal feeding amount, then gradually transition to free feeding, and ensure an adequate supply of clean drinking water.