Nicholas Schneider, DVM Schneider Veterinary Services, LLC.

Milliken, CO

Main functions: Produce Ova Production of

estrogen/progesterone Establishment and maintenance of

pregnancy Normal cycle length: 18-24 Days Estrus typically lasts: 1-4 days!

Varies! Less in gilts

Typically ovulate ≈ 40 hours after onset of estrus Variability is great (10-85 hrs) Rule of thumb is 2/3 estrus length This is why we breed multiple

times Show heat throughout year

Not seasonal like sheep/goats

Goal is to maximize pigs/sow and to minimize costs!! One is usually at the expense of another! Must find middle-ground. Owner and operator must

define their goals and then strive to achieve them

Signs of heat (estrus) Primary Sign (Gold Standards):

Standing while another sow mounts Back pressure test (pressure applied on back like boar

mounting) Secondary Signs:

Red, swollen vulva Increased/changed vocalization Increase in vaginal mucous Increased activity

Courtesy of Purdue Univ.

Critical to reach optimal weight Weight more important than age! 300-350 lbs. (commercial down to 260 lbs) Litter size, milk production, ability to breed back for parity 2,

ease of birth

Heat abatement /protection from cold Can stop them from cycling Negative energy balance

Must have proper plain of nutrition and water access!!!!!

More important than anything else!!!

Rix and Ketchem, 2010

Prepuberal defined as have not been in estrus yet.

Techniques used to control these animals very different than “mature” females.

Tough to gauge what age the pigs will be prepuberal because of nutrition differences Commercial barns anticipate 160-180 days

Boar exposure Exposure of mature boars (>12 months old) to batches of

gilts Pheromones from the boar act to “kick-start” cycling

Provide exposure daily for 5-10 minutes Physical, nose to nose, contact is helpful if housed near

gilts 70-80% gilts show estrus in 28 days

40% in 10-14 days

PG 600 (hormone of 400 IU eCG w 200 iU hCG) Currently not available, potentially discontinued

indefinitely

Treatment with PG600 can induce Prepuberal gilts Injection to estrus interval is 4-6 days typically 60-70% estrus (last 1-2 days) 70-80% ovulate (30-40 hours after onset)

Some use with boar exposure

Increase response 10-20%

Should I breed on first heat? Answer is…it depends.

Expectations Economics

Traditionally, litter size is decreased on first heat Commercial data says around 0.5-1.0 live pig/litter (Kirkwood, et. al,

2000) Depends on maturity of gilt at time of breeding Breeding on 1st heat does not alter lifetime production

(Kirkwood, et. al, 2000) Economics may outweigh additional pig

In most niche systems/show pigs, that additional pig can pay economic dividends

Observe for heat Think back to primary and secondary signs

Once or twice/day heat detection

Twice/day heat detection allows us to more accurately identify onset of estrus

Unfortunately, heat detection is not best around feeding time!!

Competition and eating changes behavior

Feeding Matrix (a synthetic progesterone) Extends the time period to the next ovulation by acting like

progesterone Feed 6.8 mL/gilt/day for 14 Days

MUST FEED FOR 14 DAYS AT THAT DOSE Can cause cystic ovaries if doses are missed

Observe heat in 4-9 Days Some follow with PG600 (claim to shorten time to estrus)

Little to no effect on initiating follicle development or ovulation!

Not successful/worth it in my opinion

Typically how sows are inseminated in commercial barns

After weaning (roughly 21 days), sows are inseminated again 3+ days later.

Litter size typically is largest 3-4 days post weaning, versus longer. Farrowing rate % is also typically larger.

Key is to not have a lot of condition loss during lactation. Also, avoid overfeeding during estrus as that can effect litter size.

Want to maximize fertility with lowest semen costs Maximum fertility for eggs is 8-12 (potentially up to 20

hours) hours after ovulation Sperm is able to successfully fertilize 12-24 hours after

insemination Must go through the process of capacitation Changes the sperm must go through to be able to

successfully complete insemination Much depends on how often/accuracy of heat

detection! The key is getting viable sperm to fertilize viable eggs!

Sows

Rules of thumb: (Note, individual variations! Learn your pigs schedules!!!) Sows: Inseminate 12-24 hours after standing

Again 12-24 hours after 1st for as long as stand 12 hours if detecting once/day If sure you are seeing the beginning of estrus, wait up to 24 hours

My preference is earlier

Gilts: Inseminate at standing estrus and every 12-24 hours afterwards as long as standing Gilts will show heat for less time than sows, thus breed earlier

1. An adequate number of sperm are inseminated and retained (less than 20 mL backflow)

2. Semen is relatively fresh and viable (less than 40 hours)

1. Many people look at semen after inseminating to assess motility

These sample principles apply for Natural Service.

Do not expect a mature male to breed >5 females/week All females should be bred at least twice, so no more than 10

breedings/week

Key word is mature!! Younger boars <2-3 females/week

Avoid very hot and cold conditions. Vaccinate and feed accordingly I error on side of caution with boars. A bad boar can kill

your production. Pay more attention to the boar than anyone!

Supplies: Clean environment Lubricant Palpation Sleeves/gloves Towels Heat lamp/warming source (pigs need to be 70+F) Iodine for navel +/-Oxytocin Iron Basic antibiotic Small lamb/pig snare

Gestation is normally 112-118 Depends on many factors (animal, environmental, etc)

Signs of impending farrowing Swelling and reddening of vulva (about 4 days prior) Mammary gland becoming taut and tense (2 days prior) Mammary secretions (24-48 days prior) Restlessness and increased respiratory rate (12-24 hrs

prior) Sow stops restlessness and likely lays on side (straining

begins)

She is in the farrowing area. Everything is ready.

She is ready. Now what?

She will be on her side and straining. Abdominal straining and shivering will occur.

Small amounts of blood-tinged fluid will pass. Sometimes it is green tinged or has “pellets” in it. This is normal.

Normally within 15-20 minutes, the first pig should be born. Longer in gilts. I do not worry unless more than an hour.

Farrowing usually lasts 2-3 hours (huge variability) Piglet interval is usually 20-30 minutes. Usually, longer interval before a stillborn pig is born.

Pig is in birth canal, but does not pass in time and cannot get oxygen.

When to assist? Greater than one hour since “blood tinged fluid” and no

pig seen Greater than 30 minutes between pigs Tend to wait longer with gilts

Before assisting:

Lubricate well Be clean Be gentle

Most Important: Make sure you are where you can safely examine the sows birth canal. SAFETY FOR YOU AND THE SOW ARE MOST IMPORTANT!!

Examine the birth canal. If problems entering the birth canal, there may be problems with a small birth canal. Make your hands like a cone so you will not irritate with

fingers

If you can feel a pig, assess its confirmation

Normal Front legs retained

Courtesy of Carr Consulting

Backwards Breach

Courtesy of Carr Consulting

Only do what you are comfortable doing. Worst thing that can happen is to hurt yourself and the

sow Feel confident in what you are doing If you do not feel confident, call your veterinarian

Oxytocin is incredibly overused in the Front Range of Colorado. Oxytocin causes uterine contraction. If an obstruction, does

more harm than good. Never use oxytocin before checking birth canal for obstruction!! Think pigs as cars and the cervix as an exit. Not all the cars can exit

at once. If they all try, you get a pile-up! Higher number of stillborns!

Same effect as oxytocin from stimulating natural oxytocin release by vaginal palpation or rubbing the udder with a warm towel.

Limit oxytocin to gilts and sows with history of problems. If sow is farrowing normally, never use until after 6th-7th pig. Limit two doses (1/2 cc) per sow/gilt.

Ensure the piglets are in a dry and warm environment Dry off with a towel if need be. Deep straw bedding or under heat lamp. Iodine dip navels (especially show pigs)

Ensure mom is allowing pigs to nurse ID small pigs, chilled pigs, slow-to-nurse pigs Help if needed.

Colostrum is critical. Sometimes best to do split suckling

After largest pigs have nursed, remove from litter and place in heated box for 1-2 hours. Give the sow 1/2cc oxytocin and allow small pigs to nurse. Repeat this procedure in the morning and afternoon of first 24 hours.

Sow should “clean”/pass placenta in less than 4 hours. If placenta does not pass, be concerned with more pigs in birth canal.

200 mg Iron Dextran at 2-3 Days

Thank you for your attention.

Nicholas Schneider, DVM Schneider Veterinary Services, LLC. Milliken, CO nickschneiderdvm@gmail.com