Liver Fluke. Acute Fluke - sheep. Chronic fluke. Costs of liver fluke in adult sheep. Fluke Risk throughout the year

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1 What can farmers do to protect against liver fluke? Liver Fluke Over a wet summer... Numbers of snails Numbers of fluke within the snails Dr F. M. Lovatt BVScPhD DSHP DipECSRHM MRCVS leading to levels of disease in autumn & winter Acute Fluke - sheep Usually in autumn after a wet summer Chronic fluke Usually in the adult flock in late spring though increasingly seen out of season Huge numbers of immature fluke travel through the liver NB No fluke eggs in faeces as no adult fluke yet Acute liver damage Bleeding & anaemia Sudden death within 6 weeks of sheep eating fluke systs ADULT FLUKES in the bile duct suck blood NB Fluke eggs can be detected in the faeces Anaemia Dry open fleece Weight loss Ill-thrift Sub-mandibular oedema (bottle jaw or poke) Costs of liver fluke in adult sheep Poor body condition Poor fertility Poor milk supply Reduced scanning % Fewer lambs on the ground Increased ewe deaths Increased involuntary culling Increased lamb mortality Reduced lamb growth rates Fluke Risk throughout the year Risk of acute fluke in sheep Risk of chronic fluke in sheep & cattle ongoing until treatment Build up of snails & fluke numbers in environment over the summer 1

2 POST MORTEMS CHECK LIVERS OF ALL FALLEN STOCK TAKE APPROPRIATE SAMPLES USE YOUR VET YOUR FLUKE STATUS USE ABBATOIR RETURNS FLUKE TOP TIPS Abattoir Feedback NB confusion with Cysticercus tenuicollis Monitor fallen stock Suggested Timings of Fluke Diagnostics Serology on lambs to check timing of metacercarial challenge Biochemistry to check sheep liver enzymes & indicate acute disease Check ewe & cow faeces for fluke eggs (espat turn out to allow adulticidetreatment for pasture protection ) Throughout the year: Serology on lambs to check timing of metacercarial challenge Bulk milk serology Post mortems of all fallen stock Abattoir returns Check efficacy of flukicides with copro-antigen test USE YOUR VET CHECK LIVERS OF ALL FALLEN STOCK YOUR FLUKE STATUS TAKE APPROPRIATE SAMPLES USE ABBATOIR RETURNS FLUKE TOP TIPS DON T RELY ON DRUGS pastures stock WHAT ARE THE IMPORTANT PRINCIPLES OF FLUKE CONTROL? Life Pasture cycle protection Stock protection Pasture protection Stock protection Prevent sheep or cattle shedding fluke eggs on the pasture Keep stock away from snails at risk times Farm protection Quarantine protocols Photo: Moredun 2

3 Stock protection - Fencing off snail habitats Field A Silage Field No sheep this year Field B Ewes & lambs from May to August Bottom Photo James Crilly University of Edinburgh Field C Ewes February to April Ewes & single lambs May to July Water trough Field D Re-seed with drains repaired It is mid September All the sheep were fluke dosed last January The cows & calves will be housed in mid November Lambs should be fat within the next 6 weeks Summer rainfall was above average 1. Which fields have snails? It is mid September All the sheep were fluke dosed last January The cows & calves will be housed in mid November Lambs should be fat within the next 6 weeks Summer rainfall was above average WHERE DO I PUT? Fat lambs? 2. Which fields have most metacercaria? Cows & calves? 3. Which fields are high risk for fluke? Sheep bought in from wet area? 4. Which fields are low risk for fluke? Ewes? Idea by Heather Stevenson, SAC 1. What would reduce the risk on this farm? 2. What happens in a dry year? 3. What happens in a wet year? 4. How can we plan going forward? CHECK LIVERS OF ALL FALLEN STOCK TAKE APPROPRIATE SAMPLES USE YOUR VET YOUR FLUKE STATUS USE ABBATOIR RETURNS DON T RELY ON DRUGS FLUKE TOP TIPS HAVE A ROBUST QUARANTINE POLICY pastures WHICH DRUGS TO USE & WHEN stock Kill immatures in autumn & winter Kill adults in Spring 3

4 Fluke Risk throughout the year Risk of acute fluke in sheep Risk of chronic fluke in sheep & cattle ongoing until treatment Build up of snails & fluke numbers in environment over the summer What products to use? Trade names Tribex, Fasinex, Combinex, Triclacert, Triclafasor Triclamox Flukiver, Supaverm, Closiver, Closamectin or Mebadown Active ingredient Meat withdrawal Triclabendazole Closantel days days Trodax Nitroxynil 49 days Activity Kills all immature stages and adult fluke Killslate stage immature and adult fluke Albacert,Albenil, Albensure, Albex, Endospec, Ovispec, Tramazoleor Valbazen Albendazole 4-8 days Levafas Diamond Oxyclozanide 5 days Allverm or Rycoben Ricobendazole 3 days Kills adult fluke only Sheep treatment timings Treatment effective against immatures Further treatment if used closantel or nitroxynil or if high risk Treatment effective against immatures Further treatment if continued high risk Treatment with adulticide for pasture protection WHAT ARE THE IMPORTANT PRINCIPLES OF FLUKE CONTROL? Pasture protection Stock protection Prevent sheep or cattle shedding fluke eggs on the pasture Keep stock away from snails at risk times Farm protection Quarantine protocols Control of lameness in Sheep What are the costs? Dr Fiona Lovatt BVSc PhD DSHP DipECSRHM MRCVS 4

5 The Five Point Plan 1. Avoidspread of infection (in gateways, at gatherings) 2. Cullout persistent offenders 3. Quarantine bought-in sheep 4. Vaccinateto protect against footrot 5. Treatindividuals quickly and effectively Avoid Avoid spread (at handling & gathering) Bacteria spread in wet muddy soiled areas Improve drainage Think about gateways & troughs etc Separate (&treat) lame or lesioned sheep at, for example, Housing, Turnout, Weaning Footbath clean group - if good facilities Prevents spread of footrot, scald, CODD Footbath to manage scald epidemics Good facilities Clean feet before footbathing Stand on hard surface after footbathing Follow the instructions of the products used - 10% zinc sulphate for at least 2 minutes 3% (no stronger!) formalin as a walk-through Use -for lambs with scald or to control spread afterhandling NB foot-bathing is NOT EFFECTIVE to treat footrot CODD Erythromycin, Lincocinor TylanSoluble at 1g/litre Comparison of Footbaths Cull Lame ewes spread infection to the rest of the flock Keep a record of lame sheep ear tag, spray mark Cull Sheep treated for footrot more than once Sheep with badly misshapen feet, including replacement lambs Do not breed from Lambs from ewes / rams repeatedly lame with footrot BE TOUGH 3 strikes and she is out. Quarantine Necessary to avoid CODD &virulent foot rot Buy in from known source (ideally visit farm!) Reject lame sheep Enquire about vendors vaccination status & lameness policy Quarantine returning / new sheep for > 21days Inspect all feet and footbath / treat on arrival During quarantine treat promptly if become lame Discuss vaccination with vet Only add to flock once sure healthy 5

6 Treat quickly Catch lame animals asap even mild cases Focus on a minimum of 1/3 flock each day Catch, Inspect, Diagnose Treat appropriately Mark and record Topical antibiotic Spray, allow to dry & respray Don t turn onto wet grass directly or footbath post treatment Injectable antibiotic Essential for footrot& CODD Check withdrawal times especially in lambs Vaccination against Footrot Multivalent vaccine containing all UK strains of Foot rot. Discuss strategic use and timings with vet Very useful as part of a package. Two doses (4 wksto 6 months apart OK) and then a single dose each year just before the risk period for that farm. NB 1. Can cause swelling & colouring of wool at injection site care with show sheep! 2. Due to the same carrier system Cydectin 1% should not be given to sheep previously vaccinated with Footvax If there was no lameness treatment or control undertaken (!) Total cost per ewe in flock (Assumptions: cull ewe= 60; fat lamb= 70; store lamb= 40; collection of fallen sheep= 12) 0 If the farmer foot-baths in formalin once a fortnight: Total cost per ewe in flock Formalin costs 1 per litreand it takes 1hours to footbath a flock of 100 sheep) If the farmer vaccinates against foot-rot twice a year: Total cost per ewe in flock 8.70 Vaccine costs= 0.80 per dose; it takes 4 hours to vaccinate 100 ewes) If the farmer promptly catches & treats lame ewes with antibiotic & vaccinates twice a year: Total cost per ewe in flock 5.30 Vaccine costs= 0.80 per dose; Antibiotic costs= 1.30 per ewe; it takes half an hour to catch a lame ewe) 6

7 What does 3% lameness with foot-rot If the farmer promptly catches & treats lame ewes with antibiotic & vaccinates twice a year: Total cost per ewe in flock 3.60 Vaccine costs= 0.80 per dose; Antibiotic costs= 1.30 per ewe; it takes half an hour to catch a lame ewe) Thank you All slides Fiona Lovatt 7