Dr. Michael Dyck - Alberta Pork

Strategic steps for implementing improvedAI programsMichael DyckSwine Reproduction-Development ProgramAlberta Pork Regional MeetingsJune 12 & 13, 2012

Genetic Gains from AI?• Short-term Gains– Use fewer superiorboars siring slaughterpigs(Pork Storks, Australia)NucleusMultiplierSow HerdSlaughter• Long-term Gains– Reduced “genetic-lag” innucleus-multipliercommercialpyramid(John R. Cosgrove, Banff Pork Seminar, 1996)

Key ConceptStrategically use geneticallysuperior boarsSemen concentration/AI doseNumber boars neededGenetic index

Not all boars are created equal……A single sperm is half apig …………it probablyrequires < 1 thousandsperm at the site offertilization to producea litter….

Current AI practices:Q. How many sperm are used to produce a litter?A. 5-9 billion (2-3 inseminations at 2.5 -3 billion sperm/dose)The excessive number of sperm used per litter born• Increases the numbers of boars needed forsemen production• Reduces the genetic impact of our best boars

Not all boars are created equal!Reproductive Performance– Despite “rigorous” semen evaluation, certain boarsdo not have the same reproductive performance– Research has shown• Some boars have lower fertility if numbers of sperm perAI dose are reduced (2 billion) even though they have“normal” semen characteristics at the AI stud (15-20%boars), while others maintain their fertility• Current AI dose of 2.5-3 billion sperm compensates for aminority of boars in production.

Limitations of using Pooled SemenCertain boars have lower fertility if numbers of sperm per AIdose are reduced (say < 2 billion)- Therefore, “diluting” sperm numbers of morefertile boars within a pool with sperm from boarsthat produce few offspring at lower sperm doses isan ineffective strategy when trying to maximizethe impact of AI- Use of pooled semen breaks the link betweenknown genetic value of individual boars and thepaternity of progeny produced.

Litter Size Data for 31 Boars(minimum of 50 matings/boar)Tony Chandrauk - Personal Communication

Not all boars are created equal!What is stopping us from achieving gains inproduction by better utilizing our best boars?1. We don’t assess relative fertility of boars with high geneticmerit when used with low numbers of sperm per AI dose.2. Use of pooled semen from boars with different, butlargely unknown, “relative” fertility.3. Limited application of advanced AI technologies withsemen from superior boars• Post-cervical AI (PC-AI)• Fixed-time AI (FT-AI)

Benefits of Post‐cervical AI (PC‐AI)PC‐AI = semen deposition in the uterine body of the sowso fewer sperm are needed per insemination(also referred to as intra‐uterine insemination‐IUI)• Reduces semen requirements by reducing the number of spermneeded per insemination• Allows boars of higher genetic merit to be more widely used.• No semen backflow & efficient procedure to deposit semencloser to point of fertilization

Benefits of Fixed-time AI (FT-AI)FT‐AI = hormones (e.g. Lutropin – Bioniche) usedto control ovulation in sows of gilts so only oneinsemination is needed.• Reduces semen requirements by reducing the number ofinseminations needed to produce a litter• Allows boars of higher genetic merit to be more widelyused.• Reduces labour needed for estrus detection and multipleinseminations

Steps for Improved AI programs1. Identify boars with acceptable fertility• Characterize boar fertility using Single-Sire matings2. Eliminate boars with for limited reproductivecapacity at lower sperm doses (2 billion)3. Use boars with proven fertility with AI technologiesthat require less sperm PC-AI or FT-AI4. Retain boars with the highest genetic merit (EBVs)for producing commercial progeny

Research Trials• University of Alberta & Industry Collaborators• Objective: Decrease semen concentration per AI dose toimprove the use of genetically superior boarsPhases of the trial:1. Prove boars at entry with single-sire matings (SSM) at2B viable cells using multiple doses2. Move whole system to SSM with 2B viable cells3. Move to SSM of sows with 1B viable cells using PC- AI

2 BillionCharacterize boarfertility usingsingle-sire AI.Moving towards more efficient andimproved AI .............Evaluating the true potential ofa boar• 50 Single sire matings per boar at aconcentration of 2 Billion sperm• Production characteristics measured:- Pregnancy & farrowing rate- Litter size (total and alive)Single sireMultiple breedings,standard AI

D30 Pregnancy & Farrowing Rate100%95%90%PRFRRate85%80%75%70%65%60%32%1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64Boar

Unproven boars2 Billion2 BillionProven fertile boarsCharacterize boarfertility usingsingle-sire AI.33%Removals due tolow production &overall value.15-20% due tofertilitySingle sireSingle sireMultiple breedings,standard AIMultiple breedings,standard AI

Factors contributing to the value of the boarNPDNPDEBVFarrowingRateLitterSizePigsProducedOthers?(survivability)

Contribution Index (CI)Value of pigs produced (estimated per 100 sows)= Farrow rate * Born Alive * Index * Value (7¢/index point)Boar Value ($)20001800160014001200100080060040020001 4 7 1013161922252831343740434649525558616467BOAR

Unproven boars2 Billion2 BillionProven fertile boars1 BillionCharacterize boarfertility usingsingle-sire AI.Removals due tolow production &overall value.Removalsprimarily due tooverall value.33%33%Single sireMultiple breedings,standard AISingle sireMultiple breedings,standard AISingle sirePCAI and/or FixedTime Insemination

Economics for Holden Farms: (40,000 Sows)AI method Standard Standard PC-AI (Sows) Standard (Gilts)AI dose (billion) 3 ¯ 2 ¯ 1 2# Inseminations 2.4 = 2.4 ¯ 2.4 2.4# boars needed 231 ¯ 155 ¯ 61 31Average index 115 + 118 + 123 123# Sows/Gilts 40,000 = 40,000 = 32,000 8,000Pigs/Sow/Year 25 + 25 = 25 25W-to-F losses 7% = 7% = 7% 7%Total pigs 1,000,000 = 1,000,000 - 800,000 200,000Sold/year 930,000 = 930,000 - 744,000 186,000Value per pig $0.07 = $0.07 = $0.07 $0.07$416,640 $104,160$7,486,500 $7,681,800 $8,007,300Annual Opps: $195,300 $520,800(Diff 2 & 3B) (Diff PC-AI sows & 3B and gilts 2 & 3B)(Williams, 2011)

Take-home MessageStrategically use geneticallysuperior boarsSemen concentrationNumber boars neededGenetic index$0.80 to $1.31 per pig(Williams, 2011)

THANK YOU!!

Future Directions: On-going StudiesBoar FertilityParametersGenotypic SNPProfileSeminal PlasmaProteomic ProfileGenomic & Proteomic Markersof Boar Fertility