PRRS Control Practitioner s View. John Hayden BVSc MRCVS Integra Veterinary Services

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1 PRRS Control Practitioner s View John Hayden BVSc MRCVS Integra Veterinary Services

2 PRRS diagnoses trend and seasonality (data for Q3 and 2015 incomplete)

3 Viruses PRRS and swine flu predominant PCV2 associated disease lower level Mycoplasma hyopneumoniae (Mycoplasma hyorhinis) Bacteria Main PRDC pathogens in GB Haemophilus parasuis predominant Pasteurella multocida mainly secondary APP declining Bordetella bronchiseptica, Trueperella pyogenes Streptococcus suis common concurrent disease Parasitic pneumonia

4 Disease detection: Diagnoses concurrent with PRRS in 2014: Syndrome Diagnosis Number PRRS (total) 49 Systemic Streptococcus suis 13 (13) PCVAD 0 Respiratory Past. multocida 17 (27) Haemophilus parasuis 5 Enteric (10) Other (9) Swine influenza 0 Mycoplasma 3 APP 2 Salmonellosis 7 Gastric ulceration 1 E.coli 2 Trueper. pyogenes 5 Unusual other 4

5 Cost of PRRS 70 per sow per year 3.50 per finisher pig Xavier de Paz PRRS cost for the European swine industry. cost for theeuropean swine industry_10069/

6 Where were we? Pre 2001 Sows herds experienced regular waves of infertility, abortions, low viable pigs Porcilis PRRS off licence use in breeding herds started to stabilise immunity across the herd Used once per cycle 7 10 days after farrowing to start with Then mid pregnancy 6 10 weeks in pig.

7 Stability and Control Use of Porcilis PRRS in most herds once per cycle Porcilis PRRS in boars 6 monthly Negative repops to insure against breakdown Introduction of only negative stock and then vaccinate on entry Closed herds testing of gilts at 15 weeks, before vaccinating to monitor Production of virus negative pigs Rearing and finishing negative Ability in some instances to eradicate PRRS altogether Good times

8 Then what? 2006 first East Anglian reports of novel strains later found to be different on the dendrogram from the original Lelystad and Porcilis PRRS viruses

9 Then what? 2006 first East Anglian reports of novel strains later found to be different on the dendrogram from the original Lelystad and Porcilis PRRS viruses PRRS symptoms despite vaccination. Breakdowns in negative but vaccinated sow herds detected in off site finishing

10 Diversity in Britain over time (ORF5-based): 1990s

11 Diversity in Britain (over time):

12 Diversity in Britain (over time):

13 Diversity in Britain (over time):

14 Diversity in Britain (over time):

15 Diversity in Britain (over time):

16 Diversity in Britain (over time):

17 Where are we now? Despite heavy use of vaccine sometimes up to 4 x before a maiden gilt farrows and twice a cycle for sows we have some herds testing strongly PRRS positive on PCR. Some herds have stopped using vaccine altogether and the problem has burnt out (VLA meeting, Feb 2015) Other vaccines dead and alive are available but I have not tried them

18 Is it all about vaccines?

19 Monitoring Bloods 12 unvaccinated pigs, every 3 months Rope tests PCR / antibodies

20 New tools ReproCyc PRRS EU 2ml for sows PRRS Flex EU 1ml for piglets / growers Unistrain PRRS

21 Whole herd PRRS elimination

22 Experiences since August 2015 ReproCyc PRRS EU used as a blitz to stabilise the herd by vaccinating ALL boars, sows, gilts and weaner gilts over 30kg Day 0, Day 21 and then every 15 weeks All stages of pregnancy / lactation Virus has nowhere to hide Reduced transplacental transfer so aim is no viraemic pigs are born

23 Herds done Gilts at all stages of pregnancy Sows at all stages of pregnancy Some returns after first dose, but within 2 days of the injection so in theory too soon to be due to the vaccine Second dose no observed problems 2 full herds done in November

24 Planned 3 rd dose after 15 weeks Full herd 2 nd doses in December

25 Spreadsheet to calculate vaccination dates etc PRRS Programme to produce PRRS free weaners 15 Oct 15 Vaccinate all weaned pigs at weaning with PRRS Flex EU : 15 Oct Nov Mar Apr 16 Vaccinate all sows, boars, gilts on site with ReproCyc PRRS EU : 26 Nov Dec Mar Jul weaned pig blood tests # 28 Jan Mar Apr Jun Jul 16 If weaned pig bloods are negative stop vaccination of weaners 04 Aug Sep 16 Weaners monitored ## ALL INCOMING GILTS & BOARS ReproCyc PRRS EU on entry # Ear swabs to SAC for PCR PRRS before PRRS vaccination ## 6 bloods for PCR and ELISA from each batch on site

26 New monitoring ideas PCRs done at SAC Edinburgh from: Drop of blood on a swab / cotton bud from earprick Possibly tail stump blood drops on a cotton bud Possibly tails removed at docking

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28 Aim 1 Production of PRRS negative weaned pigs

29 Aim 2 PRRS negative rearing and finishing pigs

30 Aim 3 Think about regional eliminations

31 Acknowledgements Susanna Williamson (APHA Bury St Edmunds) Jean Pierre Frossard (APHA Weybridge) PH Rathkjen (Boehringer Ingelheim Animal Health)