Development of the sow caliper 2014 Swine Educators In-Service October 1, 2014 Knauer, M. T., and M. Bryan mtknauer@ncsu.edu

NCSU Swine Extension Specialist Focus Swine genetics and production management Appointment 70% extension, 30% research Start date – July 2011

Training graduate students Animal Science – Animal Breeding & Genetics M.S. (4) John Langdon Cassie Ferring Austin Putz Matt Morrison PhD (2) Emily Cook Miranda Bryan

Selection for improved reproduction under heat stress Evaporative Cooling Genetics of piglet quality Pellet quality Selection for improved reproduction under heat stress Sow body condition

Outline Making a case for objective body condition tools Research associating body condition and reproduction Economic impact of implementing the sow caliper Example feeding strategies Summary

Sow feeding management concepts Repartition gestation intake to lactation Reducing gestation feed intake improves Feed cost Subsequent lactation feed intake Increasing lactation feed intake improves Litter weight gain Wean-to-estrous interval Subsequent farrowing rate Subsequent litter size Cull weight

Concept of repartitioning gestation feed to lactation Superior reproductive throughput

Feeding based on visual body condition Pros Cons Requires continuous training Farm to farm variation Potential for reduce profitability Inexpensive

Problem – visual BCS If you cannot objectively measure body condition How will you manage it? will you improve?

Validating problems with BCS Thin Optimal Fat Sow caliper score

Differences in body condition Farm 1 Farm 2

Problem – visual BCS Underfeeding Overfeeding Impaired reproduction High feed costs Farrowing problems Increased preweaning mortality Impaired reproduction Well-being concerns

Problem – visual BCS High feed costs Farrowing problems ↑ preweaning mortality Problem – visual BCS Impaired reproduction Well-being concern Optimal Sow caliper score

Adoption of objective body condition tools Standardize farms & people Train new/existing employees to visually score sow condition Fast and accurate tools will reduce weaned pig cost

Exp. 1 – Define ideal body condition in relation to reproduction Commercial sow farm in eastern NC August 2012 - May 2013 1,500 whiteline sows Multiparous

Sow housing Stalls Pens Weaning to ~35 days ~35 days to farrowing 8×10ft 4 to 5 sows per pen

Body condition traits Caliper score (CS) Weight (WT) Backfat (BF) Loin eye area (LEA) Visual BCS 1-5 by experienced technician

Using the caliper – find the last rib

Knauer sow body condition caliper An objective body condition tool – the sow caliper Slides 10 & 11 are fine.

The concept… Adapted from Edmonson et al. (1989)

The concept… Adapted from Edmonson et al. (1989)

Statistical analysis Data analyzed with SAS using PROC GLM Fixed effects group barn group x barn interaction parity Example model reproductive trait = group + barn + group*barn + parity + body condition trait

Relationships between body condition measures at breeding with subsequent reproductive performance CS CS2 WT BF LEA LEA2 BCS BCS2 NBA BW NW WW PS WCI = (P<0.05) 2Denotes quadratic body condition term. NBA= number born alive, BW= litter birth weight, NW= number weaned, WW= litter weaning weight, PS= piglet survival, WCI=wean-to-conception interval.

Optimum sow caliper score for piglet survival

Lighter weight sows had greater piglet survival Parity p>0.05

Optimum sow caliper score for reproductive throughput

Exp. 2 – Define ideal body condition change in relation to reproduction Commercial sow farm in eastern NC 885 sows 250 gilts Smithfield Premium Genetics February to August, 2013

Farm body condition score Traits measured Ultrasound backfat Sow caliper Here are the two most common objective body condition tools. On the left is an A-mode ultrasound machine measuring backfat. Recommended backfat levels for gestating sows are 0.7 to 0.8 inches measured at the 10th rib. On the right is a sow body condition caliper. The caliper is a composite measure of weight, backfat and muscling. Current recommendations for the caliper define optimal as between 12 and 15 at the last rib (P2 location). 2 3 4 Heart girth (gilts) Farm body condition score

Backfat, BCS, caliper and gilt weight traits Gestation gain Gain late gestation Gain early gestation gestation breeding day 35 day 105

Statistical analysis 24 body condition traits related to reproduction Data analyzed with SAS using PROC GLM Fixed effects farrowing group parity Example model reproductive trait = farrowing group + parity + body condition trait

Results – in general Reproduction associated with Gilts Sows body condition change but not specific body condition Sows specific body condition but not body condition change

Results - gilts = (P<0.05) At breeding Day 35 of gestation Early gestation gain Late gestation gain Gestation gain Backfat NBA STB NW BCS Caliper score Weight = (P<0.05) NBA= number born alive, STB= stillborn, NW= number weaned.

Results - sows = (P<0.05) At breeding Day 35 of gestation Early gestation gain Late gestation gain Gestation gain Backfat NBA STB NW BCS Caliper score = (P<0.05) NBA= number born alive, STB= stillborn, NW= number weaned.

Gilts that gained condition during gestation farrowed fewer piglets

Identifying “ideal” sow body condition Exp. 1 Exp. 2

Benchmarking gestation feed intake Gestation feed intake per day, lb. Agri Stats 2005 to 2010

18,000 sows - implementation of sow caliper in 2013 savings of $285,000, $15.82 per sow 8 farms – 18,000 sows

18,000 sows - implementation of sow caliper in 2013

Fast improvement in sow herd body condition possible Average herd caliper score improved from 18.2 to 15.0 in four months Optimal

Implications – feeding management increase feed 2 lb caliper ≤ 11 = 5 lb caliper =12 to 15 = ? lb caliper ≥ 16 = 3.5 lb 3.5 lb Gilts Gestation breeding ~day 7 day 93

Implications – feeding management Sows increase feed ??? caliper ≤ 11 = 5 lb caliper =12 to 15 = ? lb caliper ≥ 16 = 3.5 lb ad libitum Lactation W2E Gestation breeding day 93

Implications – feeding management increase feed 2 lb caliper ≤ 11 = 5 lb caliper =12 to 15 = ? lb caliper ≥ 16 = 3.5 lb 3.5 lb Gilts Gestation Sows breeding ~day 7 day 93 increase feed ??? caliper ≤ 11 = 5 lb caliper =12 to 15 = ? lb caliper ≥ 16 = 3.5 lb ad libitum Lactation W2E Gestation breeding day 93

Implications – feeding management Feeding level for “ideal” females may vary between farms Variation in drop boxes, etc. Caliper usage Gilts ~7 days after breeding every 3 to 5 weeks - as needed Sows at breeding 90% of sows should be “ideal” (caliper score of 12 to 15) at day 93 of gestation

Summary Repartitioning gestation feed intake to lactation can improve herd reproduction/profitability The sow caliper is an objective tool that can be used to manage body condition We recommend maintaining sows at a caliper score between a 12 and 15 Sow calipers are available to the public – contact mtknauer@ncsu.edu

Summary Sows “Ideal” body condition in relation to sow reproductive throughput was identified Heavy sows have greater preweaning mortality Gilts A one caliper score increase in body condition during gestation decreased NBA by 0.57 piglets

Body condition extension materials Sow body condition poster Free Available @ pork.org – Pork Store

Thank you Dave Baitinger Dr. Dustin Kendall Mark Daughtry Tommie Dale Bob Ivey Stacey Jones Dr. Cary Sexton Miranda Bryan Frank Hollowell

Mark Knauer mtknauer@ncsu.edu Thank you for your time Mark Knauer mtknauer@ncsu.edu