Sheep Flashcards

Question

Clinical signs of hypocalcaemia in sheep?

Answer 1

``` Initial weakness and excitement Progresses to recumbency Dilated pupils Constipated Bloated Collapsed Flaccid paralysis Comatose -> death ```

Answer 2

Slow IV 40-80ml 20% calcium boroglucoronate or very slow 20-40ml 40% - rapid response SC 1ml/kg 20% CaBG (50-100ml) warm - slow response Monitor as may relapse

Answer 3

History: post lambing/peak lactation, lush grass/bare pasture Rapid onset Sudden death usually Neurological signs - excitable, tremors, recumbent, hyperaesthesia, convulsions, death/found dead

Answer 4

IV 40-80ml 20% Calcium | SC 50-80ml 25% MgSO4

Answer 5

``` Hypocalcaemia Hypomagnesaemia Pregnancy toxaemia Listeria Mastitis Metritis ```

Answer 6

NSAIDs Epidurals Antibiotics Give lamb colostrum

Answer 7

Dead lambs which are not possible to deliver per vaginum Lots of lube Remove forearms - cut through skin around leg above carpus, then up towards elbow, undermine attachment of shoulder to chest wall, pull leg off Repeat other if necessary

Answer 8

``` Over sized lambs Ringwomb (failure of cervix to dilate) Vaginal prolapse Foetal monster Malpresentation ``` Contra: rotten lamb/smelly fluids unless can exteriorise uterus (embryotomy or euthanasia best)

Answer 9

Broad spectrum antibiotics (5 day coverage) NSAID Local anaesthetic - local infiltration (40ml total), inverted L block or paravertebral T13, L1, L2, L3, 5ml procaine/site), sacra-coccygeal epidural (with xylazine)

Answer 10

Incise half was between last rib and wing of ileum, 10-15cm below transverse processes 15cm incision Skin and SC tissue with scissors External and internal abdominal oblique, then lift transverse and peritoneum before incising (so don't puncture rumen) Grasp uterine horn and exteriorise Incise 10-12cm with scissors Remove lamb Check for other - reach into other horn, can make another incision if needed Suture uterus with continuous inverting pattern - catgut, clean, can do 2 layers Peritoneum and transverse, then internal and external abdominal obliques with continuous simple catgut Skin - ford interlocking, simple interrupted or other, nylon Blue/yellow spray Can give sheep oxytocin after to involute uterus and protect the sutures (1-2ml) Feed lambs!

Answer 11

dystocia - poor hygiene, dead lambs | Post abortion

Answer 12

Dull, recumbent, depressed Toxaemia - congested mucous membranes Red/brown or purulent vaginal discharge

Answer 13

Antibiotics and NSAIDs Poor prognosis Prevent with hygiene

Answer 14

Common in last 4 weeks of pregnancy (1-2%) Vagina or vagina and cervix, may include bladder Inflamed swollen infected tissues, obstruction of bladder, urine retention Can be fatal if untreated

Answer 15

``` Prolific breeds > hill breeds Litter size Age Obesity Hypocalcaemia 35-40% will re-prolapse ```

Answer 16

Retention devices - discomfort, irritation of mucosa, secondary infection Harnesses - avoid pressure sores NSAIDs Long acting antibiotics Surgery Cervix post-lambing - same and mark for culling Prevention - difficult as cause uncertain, cull as increased risk, put harness on before occurs next lambing, review poss risk factors

Answer 17

Epidural anaesthetic - reduce straining, analgesia, sacra-coccygeal or first intercoccygeal space, procaine (short action) or procaine and xylazine (24h+) NSAIDs and antibiotics Clean and assess - mild chlorhexidine Replace prolapse - gently with palm of hand, raise back end of ewe Suture with obstetrical tape, purse string (leave 1.5cm opening, burner Mark ewe, remove sutures before lambing

Answer 18

Rectal prolapse Epidural, replace, purse string suture Tissue non viable - amputate rectum

Answer 19

``` Epidural Clean Remove or trim placenta Replace carefully and fully evert Suture Oxytocin Antibiotics NSAIDs Calcium? ```

Answer 20

Ewe mortality Ewe premature culling Lamb mortality Lamb poor growth

Answer 21

Staph aureus - via teat skin | Mannheimia haemolytica - via lamb's mouth

Answer 22

Peracute - cold blue +/- necrotic in gangrenous mastitis Acute - hot, red, painful, swollen Chronic - udder may be light with hard swellings (abscesses) Subclinical - abnormal milk appearance (clots) and composition

Answer 23

``` Toxaemia - congested mucous membranes? Pyrexia Tachycardia Rumenal stasis Lameness Recumbency Hungry lambs ```

Answer 24

Nutrition - undernutrition in late pregnancy/lactation, low BCS, vitamin E/selenium deficiency Concurrent disease - fluke, jones, worms, dystocia etc Prolificacy - multiple lambs Older ewes Udder conformation - abnormal teat position Udder abscesses Teat lesions - orf, over-suckling, chilling (chapped teats) Genetics Hygiene Milking practices (dairy sheep)

Answer 25

No real evidence basis Gangrenous - euthanasia (v poor prognosis) Acute - systemic antibiotics (ideally based on c+s, first line amoxicillin for 5 days, tilmicosin licensed), strip udder to remove toxins, NSAIDs, IV fluids, supportive care Chronic - cull

Answer 26

1. Ensure adequate ewe nutrition pre and post lambing 2. Wean lambs at 12-16 weeks abruptly 3. Control orf 4. Control concurrent disease e.g. fluke, worms 5. Don't turn out ewes with triplets 6. Cull ewes over 7/with broken mouth/udder lumps/abnormal teat positions 7. Ensure good bedding and hygiene in sheds

Answer 27

August - December

Answer 28

Spring - easy management, essential for hill and upland (limited housing, later grass growth) Christmas - intensive management (housing essential), better lamb prices at easter market

Answer 29

The pineal gland Tryptophan --> serotonin --> melatonin Melatonin only secreted during hours of darkness Hypothalamus is sensitive to melatonin during the late afternoon Coincidence of hypothalamic sensitivity and melatonin = short day breeders Oestrogen negative feedback

Answer 30

2-5 50% have 4 35% have 3

Answer 31

At least 35 days Ewes ovulate and are receptive to the ram every 16-18 days So allows for ewes that didn't conceive when first mated to be bred again at next heat Can saddle the ram to see mated ewes

Answer 32

Laparoscopy due to cervical anatomy | 12-24 hours after oestrus detected

Answer 33

Introduction of a 'novel' male or after 2+ weeks of male absence Induces cyclicity earlier in the season Can synchronise cycling sheep to some extent 2 peaks of oestrus activity after male introduction First ovulation 'silent' for some 19 days first ovulation for others 25 days second ovulation for those who had silent ovulation Use vasectomised ram so cannot fertilise Breeding males then later introduced

Answer 34

Melatonin implant at base of ear - Suffolk/Cross - use from mid May to late June to introduce ram in late June/July - Mules/halfbreds - use from early June to late July to introduce ram from mid July to late August - Day 1: 30 weeks before want to lamb - move ewes from sight/smell/sound of rams - Day 7: Implant ewes - Day 42: 30-40 days after implantation - introduce rams - Delay of 14-21 days before mating, peaks at 25-35 days - Use vasectomised ram for first 14 days to get more compact lambing period

Answer 35

Chronogest = synthetic progesterone in a sponge, place intavaginally for 12-14d to get into bloodstream Combine with PMSG (FSH activity) injections at time of sponge removal to stimulate cyclicity - only needed if out of season Oestrus 36-72 hours after sponge removal 1 ram:10 ewes Ram in 48 hours after sponge out (not earlier) Lamb in 3 week period, most in 7 days Also CIDR now licensed (real progesterone so can measure?)

Answer 36

Can use to cause luteolysis and induce oestrus in cycling animals Not authorised but can use half of cattle dose CL refractory to PG for 2-4 days Oestrus in about 40 hours 2 PG injections 7-11 days apart induces 95% of ewes in 72 hours Some data suggests lower pregnancy rates than progestergens

Answer 37

8ml Dexamethasone injection from day 140 after ram in Lamb about 40 hours later Not authorised

Answer 38

BCS 3.5 | 60+ days

Answer 39

Conception-42 days: maintenance only 42-90 days: maintenance + 2MJ/day (grass/forage) 90days-parturiton: good nutrition needed for rapid foetal growth/colostrum quality and quantity/prevention of metabolic diseases, feed according to single/twin/multiple, should be 2xmaintenance by lambing time (but reduced appetite in last 2 weeks due to rumen space)

Answer 40

Store the epididymis | Identify the animal (ear tag)

Answer 41

``` Actinobacillus seminis Haemophilus somnus Histophilus ovis Treatment unsuccessful! Prevent by growing rams in small groups, graze and rotate to clean paddocks May develop to orchiditis ```

Answer 42

Cryptorchidism (rig) - uni or bilateral, need lower temp for sperm to develop, don't put with too many ewes if unilateral Testicular degeneration - bilateral unless specific local injury Testicular hypoplasia - uni or bilateral

Answer 43

Chorioptes bovis - sheep adapted strain Crusty scabs on lower 1/3 of scrotum Crake and expose sore, weeping dermis Sore as get 'gratification reflex' when handled Can occur on lower legs and poll If extensive then raises blood flow and testes temperature --> testicular degeneration and reduced sperm quality Confirm with skin scrapes from several locations Doramectin and diazinon sheep dip effective

Answer 44

Affects rams and wethers - castrations affect development of area so urinate inside prepuce Ranges from small ulcers and discharge at prepuce to scanning?? causing blockage of the prepuce and fly strike Corynebacterium renale - also associated with off Produces ammonia from urea in urine

Answer 45

High protein concentrates and lush grass = risk factors Access to water, salt or ammonium chloride to increase drinking and acidify urine Isolate animals to reduce environmental contamination Clip wool away and clean area Systemic antibiotics and fly treatment

Answer 46

At lambing (0-48h)

Answer 47

``` Pre-partum - abortion/still birth Intra-partum: dystocia: - Birth trauma - Ruptured liver - Fractured ribs - Brain haemorrhage - Anoxia Post partum: - Hypothermia - Starvation - Infection (e.g. watery mouth, salmonella, cryptosporidium, septicaemia, meningitis, joint ill, clostridial disease) - Predation - Accidents - Congenital defects ```

Answer 48

``` Maternal factors - genotype 'mothering ability', experience, ewe health, nutrition, stress, ewe health Prenatal infections Lamb birth weight - genetics, nutrition Dystocia Colostrum/milk Hygiene - pens, lambing, equipment, navel dipping Shepherds - experience, number Weather ```

Answer 49

Inadequate immune system No energy Die of hypothermia, starvation or infection

Answer 50

50ml/kg in first 6 hours (200ml) 200ml/kg in first 24 hours (1L) Check - full belly, ewe has colostrum, watch for suckling Supplement if needed - triplets, orphans, thin ewes, dystocia, weak lambs

Answer 51

Ideal > 60g/L Minimum > 45g/L Suckling from ewe is best!

Answer 52

``` Concurrent disease - dystocia, lameness Undernutrition of ewe Breeding - mothering, lamb vigour Age of ewes Multiple births Lambing environment - stress, mis mothering, shepherding skills, poor weather ```

Answer 53

Ewe colostrum - can use oxytocin to assist milking out single ewes Goat colostrum is good - similar energy, good Ab spectrum, but CAE negative herds Cow colostrum - 2 hours of calving, jones and TB negative, vaccinated for clostridia, less energy so need 30% more Commercial colostrum - variable quality, often good energy and protein but poss less Ig, often dried cow colostrum

Answer 54

``` 50ml/kg colostrum in first 6 hours Total 250ml/kg in first 24 hours Week 1 - 300ml milk (warm) 3-4 x daily Week 2 - 1-1.25L twice daily Hay and creep feed from week 1 Wean 4-6 weeks at 15kg 0.4m squared/lamb ```

Answer 55

Early lambing flocks/outdoor lambing Usually in first 6 hours Can use brown fat for 6 hours

Answer 56

``` Bad weather Weak Premature Triplets Dystocia Infection Poor ewe nutrition Mis mothering ```

Answer 57

Warming a hypoglycaemic lamb without giving glucose first will cause a hypoglycaemic fit Oral administration of fluids to hypothermic lambs can cause regurgitation and inhalation pneumonia or asphyxia So need I/P glucose!

Answer 58

``` Will be severely weak, depressed, arched back, stands close to dam, recumbent Dry I/P 20% glucose 10ml/kg Warm to 37C Colostrum 50ml/kg Warm to 39C Return to ewe Monitor Shelter ```

Answer 59

``` Moderately weak but can still suckle and hold head up Dry Feed warmed colostrum Check ewe's milk status/health Return to ewe Provide shelter Supervise ```

Answer 60

Strength is 20% 10ml/kg warm Use 19G 1'' needle Hold lamb by front legs Just below and to one side of navel Warm in box with fan heater under wire mesh When lamb is conscious and able to suck, feed 150-200ml colostrum

Answer 61

Breeding - breed from good mothers, hardy vigorous lambs Ewe nutriton - lamb birth weight, brown fat, colostrum Provide shelter Identify at risk lambs and give special attention Lamb coats

Answer 62

E.coli - lack of colostrum or delay allows gram negative bacteria to multiply unchallenged, bacteriaemia, bacterial death releases endotoxins, lamb dies of endotoxaemia Within first 3d of birth Depressed, profuse salivation, swollen abdomen, collapse, dehydration, death

Answer 63

``` High litter size Low birthweight Early castration Inadequate colostrum Poor hygiene Later in lambing period ```

Answer 64

Oral fluids - 50ml/kg every 6 hours NSAIDs - anti-endotoxic effects Broad spectrum antibiotics - amoxicillin/clavulonic acid, spectinomycin

Answer 65

Nutrition/BCS of pregnant ewes Colostrum - check, policies Hygiene of environment Don't castrate until >24h (as would sit around for few hours as painful) Check/monitor sensitivity Metaphylactic oral antibiotics - spectinomycin in outbreak scenarios

Answer 66

Targeted oral antibiotics for prevention of WMD may be appropriate if: - Lambs born into groups where there ave been previously recent clinical cases - Triplets or low birth weight lambs born into challenging environmental conditions or towards end of lambing period But whole flock treatment of all lambs at birth should be avoided

Answer 67

``` Lamb dysentery - Clostridium perfringens E.coli Rotavirus Cryptosporidium parvum Salmonellosis (typhimurium or dublin) ```

Answer 68

Streptococcus dysgalactiae Erysipelothrix rhusiopathie Tick pyaemia (Staph aureus) Anaplasma phagocytophila?

Answer 69

Unknown? Theory: - Low carriage rate in ewes (milk, report tract?, faeces) - Direct contamination of her lambs and indirect to other lambs - Contaminated lambing environment (bedding, equipment etc) - Builds up through lambing Route of infection unsure - oral? milk? faecal? bedding? respiratory? cutaneous has good evidence - exposed surfaces such as umbilicus and wounds (docking and castration)

Answer 70

<4wo Mild or no pyrexia Moderate to severe lameness Single joint (50% of cases) or 2 or 4 Paresis, intra-vertebral joints affected Carpal, hock, fetlock, stifle most common Joints swollen, hot and painful Progress to chronic thickened joints, restricted movement, poor growth Radiographically thickening of joint capsule, osteophytic changes

Answer 71

No evidence base for treatment or control 5 day course early in disease - suggested repeat once if required, euthanise if not better Penicillin drug of choice - not sensitive to tetracyclines NSAIDs Dexamethasone

Answer 72

Move all ewes and lambs away from contaminated environment Hygiene - turnout to pasture, clean+disinfect sheds and pens between ewes, remove placentas and afterbirths, re-bedding frequently, wear gloves when lambing, wash hands between lambing, disinfect all equipment between lambs Ensure colostrum intake Navel dipping in 10% iodine by 15mins old and repeat 2-4h later Metaphylactic treatment of neonatal lambs in outbreaks but don't continue in successive years

Answer 73

6 weeks - 6 months old Polyarthritis (fibrinous), pyrexia, lameness, stiffness High morbidity

Answer 74

Ubiquitous Commensal and pathogen Faces, urine, saliva, nasal secretions, carrier animals, wild birds Environmental contamination Skin wounds - surgical castration and docking sites, umbilicus? Post dipping

Answer 75

Penicillin daily for 5 days NSAIDs Control - clean, dry lambing environment, hygiene of wounds and navels, vaccination licensed for pigs

Answer 76

``` Hunched back Poor body condition Poor suckling Moist, swollen, painful navel Pus from navel Spreads to joints ```

Answer 77

Poor prognosis Broad spectrum antibiotics for at least 5-7d (penicillin etc) Prevention same as joint ill

Answer 78

Opportunistic bacteria, inadequate colostrum Weak, depressed, collapsed, fitting Congestion of blood vessels around the eyes Prognosis poor

Answer 79

1-3 weeks old Acute ataxia and uncoordinated tendency to recumbency Death quickly follows usually within 24-48 hours

Answer 80

Clinical signs and lab confirmation Biochemically lambs may be weakly azotaemic and hyperphosphataemic All have metabolic acidosis due to excess D-lactate (due to colonic fermentation)

Answer 81

Sodium bicarbonate dissolved in tap water orally with parenteral long acting amoxicillin

Answer 82

Treat early - check at birth | Flip out lid, sub-conjunctival injection with penicillin, staples

Answer 83

``` Use small amount of local Incise skin where anus should be Identify and open blind rectum Evacuate Suture rectal wall to skin ```

Answer 84

``` Gaseous GA Surgically repair Clean intestines with sterile fluid Enlarge hole Replace Suture defect Good aftercare ```

Answer 85

Umbilicus swollen (ddx hernia/abscess) Dribbling urine (ddx urolithiasis) Surgery under GA to locate Usually need antibiotics as infection common

Answer 86

Copper deficiency | When ewes deficient in pregnancy

Answer 87

Still births Weak lambs Characteristic weakness of pelvic limbs Delayed form in offer lambs

Answer 88

Scottish blackface

Answer 89

Copper injections/boluses/capsules

Answer 90

Ewes grazing pasture or crops with high goitrogens Newborn lambs - hypothermia, starvation, pot bellied, weakness, death Thyroid gland goitre in lambs Late abortion PM: goitre gland:bodyweight ratio

Answer 91

Treat ewes with potassium iodide 4 weeks pre-lambing or boluses

Answer 92

Single: 5.5-7kg Twin: 5-6kg Triplet: >4kg

Answer 93

``` Swollen head/tongue Meconium staining Oedema of head and shoulders Fractured limbs and ribs Free blood in carcass Haemorrhages Hepatic rupture ```

Answer 94

No brown fat | No milk in abomasum

Answer 95

``` EID and electronic scales, or traditional weigh scales and paper Pick typical group of lambs (known age) Assume 4kg birth weight 8 week weight - 300-500g/day Weaning weight - 300-500g/day Sale weight - 200-250g/day ```

Answer 96

``` Low birth weight Border disease Congenital problem Neonatal/chronic infection Inadequate milk - triplets, too little milk, bottle fed, weaned too early ```

Answer 97

``` Inadequate nutrition Parasitic disease - esp anthelmintic resistance Trace element deficiencies Pneumonoa Lameness - joint ill, CODD, FR/scald Off, scab ```

Answer 98

``` E.coli Salmonella Clostridium perfringens type B (lamb dysentery) Clostridium perfringens type D (pulpy kidney) Cryptosporidium parvum Coccidiosis Nematodirus battus Parasitic gastroenteritis Acidosis ```

Answer 99

``` Severe outbreaks at end of lambing/calving Intensive systems Lambs 3-7d old Profuse diarrhoea (blood) Dehydration Can be fatal ```

Answer 100

Stain faecal smear C parvum PM histopathology (definitive) Check for E.coli

Answer 101

Supportive treatment - house, oral fluids (50ml/kg 4-6xdaily) No drugs licensed Prevention - use different fields/housing for lambing and calving, move to fresh pasture in outbreak, put newborn animals to clean pasture, improve indoor hygiene

Answer 102

Eimeria crandalis/ovinoidalis Non disease causing strains normally in sheep Source is from ewes or older lambs multiplying

Answer 103

``` High stocking rates Inadequate colostrum Mixing ages Stress Concurrent Nematodirus infection ```

Answer 104

``` 4-8 weeks old Diarrhoea (can be haemorrhagic) Tenesmus Fever Weight loss Death Subclinical - poor growth ```

Answer 105

Faecal samples for coccidia count - not speciation to determine if pathogenic strain House sick animals Oral fluids (50ml/kg 4-6xdaily) Diclurazil, toltrazuril - usually group problem so treat metaphylactically

Answer 106

Reduce risk factors: Hygiene of pens and feed troughs Stocking rates Colostrum intake Nutrition Batch rearing - avoid grazing younger and older lambs together Consider prophylactic/metaphylactic treatment at risk times

Answer 107

Consumption of rapidly fermentable carbohydrates - e.g. sudden introduction of ad lib carbohydrates Stubble grain crops, wheat and barley Fall in rumen pH Lactic acid production Rumenitis Metabolic acidosis Lead liver abscessation, fungal rumenitis and death

Answer 108

``` Sudden death Dull, depressed Reluctant to move Teeth grinding Colic, bloat Ataxia, recumbent Dehydration No rumen sounds Diarrhoea ```

Answer 109

History and clinical signs Rumenocentesis pH <5.5 Rumen liquor no live organisms PM

Answer 110

``` IV fluids - isotonic saline plus bicarbonate Oral fluids by stomach tube Multivitamins Penicillin daily for 10 days Hay Review feeding ```

Answer 111

Uncommon in sheep Grain, oesophageal obstruction, legumes (frothy bloat) Left side distension

Answer 112

``` Hypocalcaemia Abdominal catastrophes Peritonitis Ascites Uroperitoneum ```

Answer 113

Stomach tube Simeticone Consider rumen trochar

Answer 114

2-12 weeks old Older lambs (>4 weeks) tend to lose condition and have diarrhoea Stand around water troughs or field drains due to increased thirst

Answer 115

Raised urea and creatinine, hyperkalaemia Decreased albumin:globulin ratio Metabolic acidosis No treatment found to be effective - tend to waste away and die within a week so euthanasia preferred

Answer 116

For red cell development, amino acid synthesis, energy metabolism - constitute of vitamin B12

Answer 117

``` Weight loss Anaemia Slow growth Debility Watery eye discharge ```

Answer 118

Cobalt rumen boluses/oral drenches Vitamin B12 injections Cobalt in creep feed Pasture treatment

Answer 119

White muscle disease - ill thrift lambs, weakness, collapse, lame Poor reproductive performance of ewes

Answer 120

North Ronaldsy Suffolk Blue faced Leicester Texels

Answer 121

Acute - ingestion of large amounts Chronic - ingestion over long time period, stored in lysosomes in liver, capacity suddenly released into circulation, may be precipitated by stress, intravascular haemolysis and jaundice

Answer 122

``` Ataxia Head pressing Jaundice Recumbency Death ```

Answer 123

Sodium calcium EDTA Supportive therapy Remove feed source Molybedenum and sulphur added to water

Answer 124

Mannheimia haemolytica Present in nasopharynx of healthy sheep - disease when enters lung Often secondary to other disease/stress

Answer 125

Pyrexia Mucopurulent nasal discharge Cough Death

Answer 126

Oxytetracycline/amoxixillin/macrolides - 5-7d Avoid stress Consider metaphylactic treatment of groups at risk or treat when signs appear Prevention vaccine - heptavac P

Answer 127

Mycoplasma ovipneumoniae | Cough, slight nasal discharge

Answer 128

Diagnosis - history, clinical signs, BAL, PM Treatment - oxytet long acting Prevention - ventilation, stocking rates, hygiene

Answer 129

T pyogenes Usually 1-2 in group Secondary to pasteurellosis infection/inhalation pneumonia Chronic weight loss, pyrexia, soft cough, increased resp effort, nasal discharge? Poor prognosis

Answer 130

Dictyocaulus filaria Muellerius capillaris - not thought to be significant Coughing, dyspnoea Baermann test - larvae in faeces Treatment - anthelmintics, antibiotics, NSAIDs, supportive

Answer 131

<95% efficacy

Answer 132

BZs: 80% of farms have resistant strains Levamisole: 47% have resistant strains MLs: 30% have resistant strains

Answer 133

Damage gut lining - reduces absorption Remove nutrients Remove blood (Haemonchus) Host immune response

Answer 134

Teladorsagia - peaks early summer Trichostrongylus - late summer/autumn Haemonchus - doesn't survive well over winter but produces lots of eggs (10,000/day/worm) - mid spring-late autumn serious outbreaks

Answer 135

Lamb to next year's lambs Most hatching and release occurs during period of chill, followed by 10-18C (some don't require chill anymore so causes disease in autumn) Large numbers of L3 hatch simultaneously Severe outbreaks of diarrhoea typically 6-12 week old lambs in late spring/early summer Clinical signs caused by invading L4 - can have disease but no eggs in faeces

Answer 136

Type 1 - lambs first grazing season, mid summer onwards | Type 2 - yearlings in winter months, emergence of hypobiotic larvae

Answer 137

Trichostrongylus

Answer 138

``` Acute regenerative anaemia Chronic hypoproteinaemia Bottle jaw Weakness, collapse Tachycardia Sudden death ```

Answer 139

Very acute severe diarrhoea | Can have high mortality

Answer 140

``` 5-6 months old Must have been exposed Nutrition Genetics Stage of production - peri-parturient immunosuppression 2-4 weeks pre-lambing until 6-8 weeks after ```

Answer 141

BZs: tubular binding, prevents glucose uptake, ovicidal Imidathiazoles (Levamisole): ganglion blocking, paralysis MLs: blocks Cl- and GABA channels, paralysis Amino-acetonitrile (monopantel): ACTH receptors, paralysis Spiroindoles (e.g. derquantel): nicotinic cholinergic paralysis

Answer 142

Broad spectrum round worms Tape worms - but not clinically significant in sheep N battus Some hypobiosed larvae Fluke (Albendazole) But has most resistance - strong probability won't work

Answer 143

Round worms and mites | All injectable forms active against mange mites

Answer 144

Don't keep for best | Use regularly as part of worm control plan, especially as quarantine dose

Answer 145

``` Treating everything Treatment frequency Over use Underdosing Biosecurity ```

Answer 146

``` 10 lambs per group 4 groups - control, BZ, LM, Ivermectin Weigh and mark Pre-treatment FEC Accurate dose of drug 7-14d post-treatment FEC Calculate mean reduction in WEC Should be >95% ```

Answer 147

Would just populate clean pasture with resistant strains so return to contaminated pasture

Answer 148

For all bought in sheep Dose with monopantel or derquantel and abamectin Plus moxidectin or doramectin to treat scab Hold off pasture for 24-48h Return to contaminated pasture

Answer 149

At lambing - leave at least 10% untreated Tupping time - only if thin Lambs - targeted to weight/FEC/use forecast/clinical signs/Famancha test

Answer 150

Famancha test | Uses pallor of eye mucous membranes

Answer 151

Group - same age/repro status/field/AH treatments Gather loosely in corner of field for 5-10 mins Collect fresh dung (at least 10 samples) Keep separate and cool - reach lab in 48h Some labs accept pooled samples

Answer 152

Monezia expansa: soft mite -> sheep - uncertain pathogenicity Taenia hydatigena: cysticercus tenucollis in sheep -> dog - liver damage, condemnation at slaughter Taenia ovis: cysticercus ovis in sheep -> dog - cysts cause muscle damage and condemnation at slaughter Taenia multiceps: coenuris cerebralis in sheep -> dog - neurological disease Echinococcus granulosus: hydatid cysts in sheep -> dog - cysts in liver and lungs, condemnation at slaughter, zoonotic

Answer 153

Thin necked bladder worm = Taenia hydatigena Sheep bladder worm = Taenia ovis Gid worm = Taenia multiceps

Answer 154

BZs for Monezia expansa in sheep Surgical removal of Taenia multiceps cysts in sheep Praziquantel every 6 weeks for dogs for all Taenia and Echinococcus granulosus Don't allow dogs to stray onto pasture Don't allow dog access to sheep carcasses

Answer 155

Scald = interdigital dermatitis = benign footrot = footrot grade 1 Footrot grades 2-4 (progression of scald) Scald is most common cause of lameness in sheep Occurs when wet underfoot

Answer 156

Dichelobacter nodosus = main pathogen | Fusobacterium necrophorum found in some cases (=polymicrobial)

Answer 157

``` Red/pink inflamed interdigital skin Necrotic focal epidermitis Discharge (white/grey pasty 'scum') Acute lameness No horn under-running No foul smell ```

Answer 158

Virulence and dose of D nodosus Susceptibility go the sheep Whether the sheep is treated promptly before separation of hoof horn occurs

Answer 159

Progressive under-running of sole of hoof horn, starting at medial aspect of sole and progressing laterally Grey necrotic pungent smelling horn Extremely painful -> rapid weight loss (reduced feed intake) Lameness Death from starvation and thirst in some cases Infection reservoir = infected foot (direct/indirect contact transmission)

Answer 160

Facultative anaerobe Survives in environment for 7 days Present in normal sheep feet Not flagellated Fastidious gram negative anaerobe Pathogenesis: - produces extracellular proteases = key for virulence - has fimbriae conferring motility and adherence - fimbrial proteins = highly immunogenic (basis of serotyping) 10 major serotypes: A-I and M

Answer 161

Anaerobe | Gut, faeces, widespread in environment

Answer 162

``` Warm Wet underfoot conditions Muddy Housing Gathering Genetics - heritable susceptibility ```

Answer 163

Topical treatment: -Oxytet spray - make sure dry before return to grazing -Footbathing: formalin 3% max, zinc sulphate - must be exposed to infected interdigital area for 2 mins, clean feet beforehand, need correct conc and depth, dry standing on concrete after, repeat after 5-7d if necessary Systemic: -LA oxytet - usually not necessary

Answer 164

Diagnosis based on clinical signs (culture based diagnosis not routine as fastidious) Treat asap! Isolate lame sheep Treat individuals/groups Injectable long acting ABs best - LA oxytet cure rate 70-80%, may need to repeat until clinical cure Footbathing: formalin, copper sulphate DO NOT TRIM FEET! Control: - footbathing - vaccination: based on fibril proteins - biosecurity, isolation and selection for resistance (culling?)

Answer 165

35-50% of farms | 0-50% prevalence on farms

Answer 166

Ulcerative or proliferative lesion starting at coronary band Progressive under-running of hoof wall downwards Frequently results in sloughing of entire foot horn capsule Very painful Grade 1 - coronary band lesion only Grade 2 - <50% horn capsule separated Grade 3 - 50-100% hoof capsule off Grade 4 - healing but still active lesion present Grade 5 - healed

Answer 167

CODD | Extensive damage to foot even down to bone

Answer 168

Treponemes strongly associated - T.medium-like/phagedenis-like/pedis D nodosus and F necrophorum also found but unknown role

Answer 169

Seasonal trend late summer/early autumn Large flock size Lowland pasture, lush pasture, poached pasture Sheep with footrot Dairy cattle in close proximity Bought in sheep Ruminant GI tract, direct contact and foot trimming equipment = infection reservoirs

Answer 170

``` Diagnosis normally visual (lameness and lesion score) Responds to antibiotics LA amoxicillin 71% cure rate Often require repeated injections Macrolides licensed in sheep Formalin/copper sulphate footbaths Topical tetracycline ``` Control: - no vaccine and host immunity not protective - regular footbathing - improve farm hygiene - don't trim infectious sheep lesions - flock biosecurity: purchase from known sources/health status, isolate lame sheep

Answer 171

1. Vaccinate twice yearly - footvax 2. Treat lame sheep quickly 3. Biosecurity 4. Environmental challenge 5. Cull chronically lame sheep

Answer 172

Footrot vaccine - treats and prevents 70-100% cure rates 60-100% protection rates May also have small protection against CODD Multivalent vaccine containing multiple D nodosus strains Oily adjuvants - site lumps Don't use prior to shearing or lambing Don't give treated sheep moxidectin 1% Initial vaccination - 2 doses 5-6 weeks apart 6 monthly booster at risk periods - post scanning (housing) and post shearing in summer

Answer 173

After 2-3 cases of lameness

Answer 174

No infection just separation of sole from wall - can carefully pare out area of separation Doesn't cause lameness unless sensitive tissue affected - impaction with stones, mud etc Can develop abscesses - heat, pain, swelling, may burst out at coronary band, pare out if necessary to release pus

Answer 175

IV regional anaesthesia Cut back granulation tissue Cauterise with disbudding iron to stop bleeding and ensure granuloma removed

Answer 176

Consequence of white line abscess Flush and antibiotics? PTS Digit amputation?

Answer 177

``` Sedation - xylazine IV regional anaesthesia or ring block around foot - procaine Clip, clean and prepare foot Antibiotics, NSAIDs Disarticulate between P1 and P2 Bandage foot Change after 3-4 days ```

Answer 178

Delays healing May spread disease to hands and clippers Studies showed treating alone with antibiotics better - foot shape will return to normal by self So trimming and topical treatment not recommended for footrot

Answer 179

``` Likely to self correct Only careful cosmetic trim Don't over trim - causes granulomas Don't cause bleeding Don't trim if infectious foot lameness! ```

Answer 180

``` Erysipelothrix rhusiopathie Number of sheep 1 week post dipping Lame, swelling above coronary band Then progresses to other joints Prompt treatment with penicillin Clean dipper tank ```

Answer 181

Proliferative scab lesions of distal limbs Orf dermatophilus Topical antibiotics and move to dry fields

Answer 182

Infectious arthritis - neonatal (strep dysglactiae), tick pyaemia (staph aureus), E rhusiopathie Non infectious arthritis - degenerative joint disease, elbows of adult sheep, unknown aetiology

Answer 183

``` Parapox virus - zoonotic Vesicular/proliferative scabby lesions - mouth/head and teats Lambs but can affect ewes esp teats 4-6 week duration Painful - Interferes with suckling/eating - Teat lesions - predisposes to mastitis - Poor growth - Death ```

Answer 184

Spread by contact Damage to skin and mouth allows virus in - rough grazing/feed esp thistles Virus doesn't survive over winter outside but scabs remain infective for long periods in dry conditions

Answer 185

Isolate clinical cases - disinfect feeding bottles etc Thorough cleaning and disinfection - steam cleaning (heat sensitive), trigene No treatment - antibiotics for secondary infection Vaccine only for infected farms (live and can cause disease, vaccine scabs are infectious, don't use indoors as will contaminate housing)

Answer 186

Psoroptes ovis - allergic reaction | Spread by direct contact or infected scab fomites material on fence posts etc

Answer 187

Kicking, scratching Wool loss, ragged fleece, moist yellow appearance Flank/dorsum/whole sheep Progressively distressed, stop eating, weight loss, seizures, death

Answer 188

Choose itchiest sheep with wool loss Edge of exudative lesions - wool pluck (seal in bag), skin scrape (put in container) Warm sample If negative sample again ELISA - detects early stages, good se and sp

Answer 189

Must consider re-infection as survive off host 17-19 days Must treat all sheep Dexamethasone for severely affected sheep Improvement in 2 weeks Organosulphate dip - must do correctly to be effective, 1 minute in dip, do not use showers Ivermectin - 2 doses 7 days apart, must move to clean grazing after first dose Doramectin - 1 dose, must move to clean grazing after first dose Moxidectin 1% - 2 doses 10 days apart, don't need to move, don't use if had footvax Moxidectin 2% - 1 dose, don't need to move, difficult to administer

Answer 190

Biosecurity Observation not enough as 7-8 weeks before see clinical signs Treat all bought in sheep Double fencing Disinfection of vehicles and equipment esp shearers and scanners

Answer 191

Ventral abdomen, scrotum Pruritis, infertility Skin scrape Organophosphate dips

Answer 192

``` Small pale red brown louse Highly host specific (sheep) Permanent parasite Spread by direct contact Chew at skin and coat - feed on skin debris and wool Like warm dark environment, not wet Shearing and rainfall reduces risk Pruritis, fleece loss Hypersensitivity and irritation Part fleece on back and flanks and look for clumps of lice Treat worst affected Synthetic pyrethroid pour ons - resistance concerns Plunge dip, diazinon, OP dip ```

Answer 193

Usually neurological but can present as primary skin disease Pruritis Notifiable

Answer 194

May to October Lucilia sericata - lay eggs in fleece, larvae hatch 12h later, proteolytic enzymes and mouth hooks Damage skinAttract other flies

Answer 195

``` Wounds Separate Depressed Foot lesions Toxaemia Death ```

Answer 196

``` Temperature - eggs need 10C to develop Humidity >65% - rainfall Shearing and fleece length Faecal soiling - lush grass/worms, tail docking Carcasses on farm ```

Answer 197

Early is best Kill maggots - synthetic pyrethroid pour ons, deltamethrin Clean woundsSupportive - antibiotics, NSAIDs, fluids House Address risk factors

Answer 198

Peri-orbital eczema Spread by contact, feeding troughs Course of penicillin injections

Answer 199

``` 'Lumpy wool' Associated with wet conditions esp after shearing Thin wooled breeds Crusty lesions with wool loss Pruritic Risk for fly strike Treat with penicillin 3-5 days ```

Answer 200

Corynebacterium pseudotuberculosis Affects lymph nodes, esp parotid Abscesses - antibiotics can't penetrate so no effective treatment Spread by close contact, fomites (shearing), resp spread (mediastinal LN abscessed rupture into airway)

Answer 201

Infected flock: Test and cull affected (culture, ELISA), hygiene of shearing, vaccination Biosecurity - disease monitoring schemes, isolate and test bought in sheep

Answer 202

St John's wort

Answer 203

Border disease - hairy shakers | Copper deficiency of growing lambs

Answer 204

Anaplasma phagocytophila Seen in tick areas upland Profound immunosuppression: - secondary infections - fever: spermatogenesis infertility of rams, abortion of ewes - Predisposed to other diseases Do become immune Bought in animals and new lambs most susceptible (no previous exposure) Control: - treat with sheep pyrethroid pour ons before entering tick area - avoid introducing naive sheep when pregnant or at tupping time

Answer 205

Staph aureus Polyarthritis/joint ill Immunosuppression Spinal abscesses/joint abscesses

Answer 206

Flavivirus transmitted by ticks Non suppurative meningoencephomyelitis Varying severity - incoordination to seizures and death Variable signs - head pressing, trembling/tremors, nystagmus, lip twitching, 'louping gait' Most infections are slight and give immunity Often young stock bought in - immunologically naive Protective immunity in colostrum, vaccine, tick control, grazing management Zoonotic

Answer 207

Season Infectious infertility - toxoplasma, border disease Ewe - BCS, age, disease Ram - age, disease, number, fertility

Answer 208

Maedi visna (MV)/Caprine Arthritis Encephalitis (CAE) accreditation scheme Enzootic abortion of ewes (EAE) accreditation Scrapie genotyping Scrapie monitoring sheme Caseous lymphadenitis (CLA) Johne's risk assessment

Answer 209

``` Birth trauma (rib fractures, dystocia) Starvation Hypothermia Clostridial disease - lamb dysentery, tetanus Meningitis Septicaemia Diarrhoea Watery mouth Intestinal torsion Predators ```

Answer 210

Clostridial disease - pulpy kidney, brassy, abomasitis, tetanus Pasteurellosis - B trehalosi, M haemolytica Urolithiasis Parasitic gastroenteritis Fluke Rumen acidosis Plant poisoning

Answer 211

Metabolic disease - hypocalcaemia/magnesaemia Parasites - fluke, Haemonchus Plant poisoning - rhododendron, yew, laurel, acorns Pasteurellosis Toxaemia - mastitis, metritis Clostridial disease - struck, blackleg, black's disease, tetanus

Answer 212

Usually when lack of other food available - starvation, snow etc Yew, acorn, laurel, rhododendron, laburnum Sudden death, severe abdominal pain, neurological signs

Answer 213

``` Bibersteinia trehalosi Normal inhabitant of URT Sudden death 6-12mo lambs Change of grazing, weather, concurrent disease Stress of handling/gathering may worsen ```

Answer 214

Sudden death | Organisms multiply rapidly and produce toxins

Answer 215

Changes in environment Injury/trauma/insult Endoparasites Poor hygiene

Answer 216

``` Anaerobic gram positive rods Grouped by organ systems: - Enterotoxaemia - Parenchymatous organs (liver and kidney) - Myonecrosis and toxaemia - Neurotropic ```

Answer 217

C perfringens -B: lamb dysentery (enterotoxaemia) -C: struck (enterotoxaemia) -D: pulpy kidney (nephrotoxic) C novyi -A: big head (rams head wounds, myonecrosis and toxaemia) -B: black's disease (hepatotoxic) -D: bacillary haemoglobinuria (hepato and nephrotoxic) C septicum -Braxy (enterotoxaemia) -Malignant oedema (myonecrosis and toxaemia) C sordelli - abomasitis C chauvoei - blackleg (myonecrosis and toxaemia) C botulinum C - botulism (neurotrophic) C tetani - tetanus (neurotrophic)

Answer 218

Enterotoxaemic and parenchymatous groups: dietary change and fittest animals - prevent with vaccination and avoid sudden diet changes Myonecrosis and toxaemia: contamination of wounds (lambing, castration/tail docking/injections/fighting wounds) - prevent with vaccination and good hygiene

Answer 219

Pasture contaminated with poultry manure | Flaccid paralysis and death

Answer 220

Contamination of docking and castration wounds Spastic paralysis, stiffness, recumbency Often not sudden death

Answer 221

``` C perfringens type B Lambs <3 weeks olf Often fit lambs Overcrowding, hygiene Severe abdominal pain, dysentery, sudden death ```

Answer 222

``` C perfringens type D Most common clostridial disease 4-10 weeks old or finishing lambs 6 months plus Sudden death May see ataxia, opisthotonus ```

Answer 223

``` Clostridium sordelli 4-10 weeks old Intensively housed creep fed lambs Sudden death Or bloat due to displaced distended abomasum ```

Answer 224

4 weeks before lambing to also protect lamb via colostrum | Then lambs from 3 weeks

Answer 225

Bacillus anthracis Sudden death Rare in sheep but don't rule out Notifiable

Answer 226

Lameness Blisters on tongue Fever Not usually fatal (but economic impact)

Answer 227

``` Culicoides imicola Up to 70% mortality Fever Swelling of head and neck Lameness Mouth ulceration Drooling Haemorrhages of skin Respiratory probelms ```

Answer 228

Causes abnormal protein to accumulate in brain causing neurological dysfunction Spreads mother to offspring prenatally and via colostrum and milk And also horizontally via birth fluids, placenta

Answer 229

``` Progressive, fatal neurological disease Long incubation period: 2-5 years Single animals Altered mental state Excitable, nervous, depressed, aggressive Tremors, ataxia, recumbency Pruritis, rubbing, scratching Weight loss Death ```

Answer 230

Altered mental state - depressed, hyper excitable, disorientated Blindness Seizures Opisthotonus - recumbent, extended front legs, flexed hind legs

Answer 231

Bacterial meningitis Cerebrocortical necrosis Pregnancy toxaemia

Answer 232

Contralateral blindness Circling Proprioceptive deficits

Answer 233

GID cysts (Coenuris cerebrally, Taenia multiceps) Brain abscesses Trauma

Answer 234

``` Altered head carriage Balance - ataxia not weakness, wide-based stance Dysmetria - high stepping Intention tremor Nystagmus ```

Answer 235

Not common Congenital - cerebellar hypoplasia Border disease hairy shaker - cerebellar hypoplasia Poss abscess (rare)

Answer 236

``` Head tilt to affected side Loss of balance Circling Falling/rolling to one side Horizontal nystagmus Aural discharge Can get facial paralysis ```

Answer 237

Middle ear infection | Unilateral facial nerve paralysis - runs close to middle ear

Answer 238

``` Depression (because of ARAS) Multiple cranial nerve deficits due to brainstem nuclei - esp V, VII, VIII, Ipsilateral hemiparesis (motor tracts passing through) ```

Answer 239

Listeriosis

Answer 240

``` No signs of central disease Depends on site of spinal cord Tetra/paraparesis Proprioceptive deficits Skin sensation Pain Pedal and other spinal reflexes ```

Answer 241

Spinal abscess - joint ill tick pyaemia Wobblers syndrome - texels Trauma Congenital abnormality

Answer 242

Border disease (tremors, hairy shakers) Congenital swayback (ataxia) - copper deficiency Drunken lamb syndrome (ataxia, depression) Lamb nephrosis (ataxia, depression) Bacterial meningitis (collapsed) Tetanus Trauma accident Spinal abscess (joint ill) Listeriosis - circling, facial nerve paralysis Louping ill

Answer 243

1mg/kg dexamethasone | Penicillin for 5 days at least

Answer 244

``` Cerebro-cortical necrosis (CCN) Listeriosis Gid Louping ill (tick area) Trauma accident ```

Answer 245

Vitamin B1 deficiency (thiamine) Acute onset in growing lambs (6-12mo) Sporadic but can get outbreaks History of diet change or worming

Answer 246

``` Vary depending on progression of disease Dull Disorientate Blind Tremors Recumbency Opisthotonus Convulsions ```

Answer 247

``` Vitamin B1 IV (slowly) Vitamin B1 IM every 12 hours For 3 days House quietly Vision should return in 5-7d ```

Answer 248

Listeria monocytogenes Associated with feeding poorly preserved silage, soil contaminated (mouldy) 18-24mo common - changing molar teeth allowing buccal tissue infection Ascending infection to brainstem

Answer 249

Encephalitis, septicaemia Anorexia Depression Unilateral hemiparesis Trigeminal nerve paralysis - salivation, food impacted in cheek Facial nerve paralysis - drooped ear, lowered eyelid, deviated muzzle, loss of blink Abortion (1-2 weeks after feeding poorly preserved/soil contaminated/mouldy silage)

Answer 250

Clinical signs CSF tap PM

Answer 251

Good if caught early Gold standard for 75kg ewe: - 6g benzylpenicillin IV - 20ml procaine penicillin IM (divided sites, one dose on day of scam) -1ml/kg dexamethasone IV - 5ml procaine penicillin daily for 5 days Supportive care Remove silage Septicaemic listeriosis at lambing - hopeless prognosis

Answer 252

Taenia multiceps Eggs ingested by sheep Develop in brain cerebrum and cerebellum (coenuris cerebralis) Dog primary host

Answer 253

``` Gradual onset Circling Contralateral blindness Head tilt Skull softening ```

Answer 254

Surgically remove cysts Good prognosis if cerebral location Poor prognosis if cerebellar location

Answer 255

Pasteurella spp Streptococcus T pyogenes

Answer 256

``` Cervical sub-luxation (paresis, rams fighting) Gid cyst Listeriosis Brain abscess Louping ill Trauma accident Pregnancy toxaemia Hypocalcaemia Hypomagnesaemia Wobbler - texels Scrapie ```

Answer 257

Infectious neurological disease of sheep Fatal, chronic, progressive brain disease of sheep TSE, prion disease

Answer 258

Very rare | Non infectious, sporadic

Answer 259

TSE testing scheme - annually, fallen and slaughtered stock and from infected flocks/herds TSE feed controls - e.g. illegal to feed animal protein to ruminants, and feeding of processed animal protein to all farmed animals SRM controls at abattoirs - specified risk material removed from sheep >6mo and incinerated (brain, spinal cord, spleen)

Answer 260

SRUC Scrapie monitoring scheme - annual flock inspection, samples and test fallen stock Scrapie genotyping scheme - breeding stock, checks for susceptibility to disease

Answer 261

Teeth/oral lesions Poor nutrition - hill ewes over winter, late pregnant ewes, inadequate grazing, poor forage quality Chronic disease - respiratory, alimentary

Answer 262

Pre-tupping - reduced ovulation so less lambs Low lamb birth weights Pregnancy toxaemia and poor colostrum quality Low milk production so poor lamb growth Ewe deaths

Answer 263

``` 8 incisors Lamb - all small 1 year - centre pair tall 2 years - 2 centre pairs tall 3 years - 3 centre pairs tall 4 years - all tall ```

Answer 264

``` Ageing Periodontal disease - bacteria - malocclusion - diet - uneven wear, feeding of root crops, mineral imbalances ```

Answer 265

Necrotic stomatitis - F necrophorum Wooden tongue - Actinobacillus lignerisei Lumpy jaw - Actinomycosis bovis Caseous lymphadenitis

Answer 266

Common! History: few days/weeks after drenching, number of sheep affected Dull, depressed, inappetent, weight loss Halitosis, pain, cellulitis Poor prognosis - euthanasia, penicillin prolonged courses

Answer 267

``` Laryngeal chondritis Jaagsiekte (OPA) Maedi visna Chronic suppurative pneumonia Mannheimia haemolytica ```

Answer 268

Abscessation of arytenoid cartilages Common in Beltex and texels Rams more common Loud inspiratory dyspnoea

Answer 269

Early Corticosteroids and broad spectrum LA antibiotics Temporary tracheostomy tube May not recover/may reoccur

Answer 270

Jaagsiekte Sheep Retrovirus (JSRV) Progressive and fatal pulmonary carcinoma Oncogenic (env gene is the oncogene) Overproduction of type II pneumocytes -> overproduction of surfactant Chronic wasting disease

Answer 271

``` Spread via lung fluids and aerosols Long incubation of 2-4y Sudden death Weight loss Increased respiratory effort Exercise intolerance Panting ```

Answer 272

``` Clinical signs Crackles and wheezing lung sounds Ultrasound - lung consolidation Wheelbarrow test - do quick and stop as soon as fluid appears as distressing for sheep, PTS if +ve PM for definitive No treatment - PTS ```

Answer 273

Biosecurity - buy from known history farms, double fencing, closed flocks Cull thin sheep/resp signs Don't keep offspring for breeding Reduce close contact housing Consider outdoor lambing Vaccine has poor immune response No reliable test to enable test and cull/testing of bought in

Answer 274

Small Ruminant Lentivirus (retrovirus) - slow progressive disease Maedi = chronic respiratory disease, can also cause chronic mastitis and arthritis Visna = neurological signs Pathology: - Infects monocytes - Progressive lymphoid infiltration and smooth muscle hyperplasia in lungs

Answer 275

Infected when young from mother's milk/colostrum, respiratory route Incubation period is several years Clinical signs >2y, usually 4-5

Answer 276

Weight loss Increased respiratory effort Exercise intolerance

Answer 277

Less common Weight loss Abnormal gait, ataxia, incoordination, paralysis Circling, head tremor etc

Answer 278

Cull Don't breed from their offspring Stocking rates, housing Difficult as by the time clinical signs seen, 50% may be infected Test and cull/create separate flocks Virus latent in genome and avoids immune system so no vaccine Buy from MV accredited stock

Answer 279

``` Eggs shed by sheep/cow Develop into miracidia Miracidia must swim and find mud snail by 24h after hatching from egg or dies! Cercariae released from snails Encyst on grass as metacercariae Metacercariae eaten by sheep/cow ```

Answer 280

Increases snail habitats Allows development of fluke eggs Miracidia can find snails Dispersal of cercariae from snails

Answer 281

>10C for miracidia to develop in egg | >15C for eggs to hatch and multiplication in snails

Answer 282

Summer infection of snails: disease in sheep in Autumn | Winter infection of snails: disease in sheep in summer

Answer 283

``` 2-6 weeks after ingestion of very large numbers of metacercariae Sept-Dec Severe haemorrhage due to migration of immature stages through the liver Sudden death Weakness Pale Dyspnoea/tachypnoea Tachycardia ```

Answer 284

Metacercariae ingested over longer time than acute Reach bile ducts, haemorrhage to liver en route Late Autumn onwards Haemorrhage anaemia Hypoalbuminaemia Weight loss Enlarged liver Submandibular and facial oedema Secondary clostridial infection - black's disease Common clinical presentation in UK

Answer 285

``` Late winter/early spring 4-5 months post ingestion Jan-March Hepatic fibrosis and cholangitis Hypoalbuminaemia Anaemia Weight loss Submandibular oedema ```

Answer 286

History and clinical signs FEC - low but often presence Haematology - hypo chromic microcytic anaemia, eosinophilia Biochemistry - AST, GLDH, GGT 13d post infection, hypoalbuminaemia, hyperglobulinaemia ELISA PM Abattoir returns

Answer 287

Fluke egg count - 12 weeks post infection, fluctuates Serum ELISA antibody - from 3 weeks post infection but only indicates exposure not whether active infection (good for monitoring naive animals e.g. lambs) Coproantigen - 8-10 weeks (2-3 weeks before fluke eggs seen), drops quickly after treatment so is used as a drench test

Answer 288

``` Triclabendazole - kills all stages but resistance probem Treat and move to low risk pasture Closantel Nitroxynil Oxyclozanide Albendazole ```

Answer 289

1. Avoid (reduce stocking density in autumn, assess farm known risk areas e.g. drain wet fields, biosecurity, closantel for bought in animals) 2. Monitor (serum ELISA, coproantigen, FEC, forecasting to predict high risk years, PM sudden deaths) 3. Targeted drug treatments

Answer 290

Autumn against immature stages (TCBZ) Winter immature and adults (Close/Nitrox) Late spring remove all adults (albendazole) High risk year/farm: - extra dose in November for immature (TCBZ) - extra dose in June for winter infection of snails (TCBZ)

Answer 291

Rotational use of drugs - use 3 causes throughout year Only use triclabendazole when necessary (autumn) Spring dose against adults important to prevent egg output and summer infection of snails Quarantine drenching - closantel/nitoxynil Test for resistance to TCBZ - composite faecal egg count reduction test

Answer 292

``` Mycobacterium avian paratuberculosis Non specific clinical signs Weight loss Anaemia Bottle jaw High parasite burdens Cattle and sheep strains - may transmit between ```

Answer 293

Can survive for many months on pasture Shed in faeces (milk) Oral route (in utero and colostrum but less important)

Answer 294

In GI lymph nodes and gut Cellular infiltration, thickening of intestines Malabsorption and protein losing enteropathy Hypoalbuminaemia

Answer 295

``` Difficult in live animals -faecal smear for acid fast organisms -serology - low se, good sp -low serum albumin -faecal culture SRUC sheep: MAP culture+PCR PM - histopath ileocaecal junction and enlarged distal mesenteric lymph nodes ```

Answer 296

``` No treatment Don't graze sheep and goats with cattle Low stocking rates Use plenty of bedding and dag ewes if necessary Cull suspected/confirmed cases asap DOn't keep offspring of infected animals Provide mains water from clean troughs Wean lambs onto grass not grazed by adult sheep this year ```

Answer 297

Ovien Infectious Keratoconjunctivitis Mycoplasma conjunctivae Mixing of sheep, tupping time or feeding

Answer 298

``` Early cases respond better Isolate affected sheep Look at risk factors for close contact LA oxytet IM of those affected Plus topical antibiotics ```

Answer 299

Listeria monocytogenes | Associated with feeding baled silage in ring feeders

Answer 300

``` Blephorospasm Cloudiness of cornea Swollen, folded iris Material in front of eye chamber Sub-conjunctival oxytet and dexamethasone Systemic penicillin Remove source ```

Answer 301

Chlamydophila abortus (Enzootic abortion) Toxoplasma Campylobacter foetus foetus (C jejuni) Salmonella abortus ovis Others: - Border disease virus - Listeria monocytogenes - E.coli - Tickbourne fever - Coxiella burnetti (Q fever - Yersinia spp - Fungi - Trueperella pyogenes - Bluetongue

Answer 302

Chlamydia abortus: - gram negative cocci - intracellular reproductive stage - extracellular infectious phase Zoonotic to pregnant women and immonocomprised people Sources of infection: - aborting ewes are main sources: discharged products of abortion heavily contaminated and viable for several days - carrier ewes less commonly: may or may not abort, shed at lambing +/- at oestrus Route of infection: - oral - close contact at lambing facilitates spread

Answer 303

1. Exposure of pregnant ewe: - if >90d pregnant, may abort - if <90d pregnant, may abort after 90d or may become latently infected by harbouring agent in reproduction tract and abort at next pregnancy 2. Exposure of non pregnant ewe: - becomes latently infected harbouring infection in reproduction tract and aborts at following lambing season 3. Ewe lamb born to infected ewes: - can become infected and abort at their first lambing 4. Exposure of a ewe who already aborted from infection: - most ewes become immune and will not abort again - some will become carriers and shed at oestrus and lambing

Answer 304

Relatively low levels of abortion in first year Abortion storms of 30% in the following year Then endemically infected flocks have abortion rate of 5-10%

Answer 305

After 90d bacteria replicate in trophoblastic epithelial cells Severe placentitis is with thickening and necrosis Placentitis: inflammation of placenta affects transport nutrients and hormone production -> death or damage to lamb Inflammation of lamb’s internal organs

Answer 306

Abortion after 90d of pregnancy, often in last month Death of lambs or birth of weak lambs or birth of one live and one dead Ewes vaginal discharge couple days Rarely sheep are ill, occasionally metritis (can be fatal)

Answer 307

Diagnosis: - abortion of well preserved lambs in late pregnancy - submit aborted lamb's placenta to lab - gross Pathology: necrotic placentitis - modified Ziehl Nielson stain: placenta, vaginal discharges or fetus to identify organsim - culture techniques - PCR available - if no abortive material can test vaginal discharges, serology on ewes (care with interpretation, paired serology is best)

Answer 308

``` During an outbreak 1) Stop spread of infection: - burn abortion material and bedding - clean and disinfect pens - isolate aborted ewes 2) Reduce further abortions: - treat remainder of flock with killed inactivated vaccine - or treat all ewes yet to lamb (>90 days) with 20mg/kg oxytetracycline long acting and repeat in 2 weeks The year following an outbreak: - vaccinate all ewes pretupping - if consider there is risk of ewes being infected from previous year, it is acceptable to repeat oxytetracycline injections the year following an outbreak (not acceptable after that) ``` Also: - clean flock: don't buy in, buy EAE accredited sheep SRUC health scheme, breed own replacements

Answer 309

Definitive host = cats Reservoir for cats is wildlife Cats shed millions of oocysts in faeces and then become immune Oocysts contaminate sheep feed and water - very resistant (>500d) Sheep ingest oocysts from pasture, bedding, feed or water etc contaminated by cat faeces

Answer 310

1. Non pregnant when exposed: develop immunity 2. Early pregnancy: - foetal resorption (ewes will present as barren) = important cause of low scanning % 3. Mid pregnancy: - foetal death - foetal retardation - mummification 4. Late pregnancy: - abortion of freshly dead lambs - weak lambs with high mortality rate - live and immune lambs - (depends on lamb and placenta's ability to deal with infection) Aborted ewes become immune In endemically infected flocks often see mainly abortion in younger ewes

Answer 311

Submit foetus placenta, or paired blood sample ewe for serology Gross pathology of Placenta: frosted strawberries cotyledons Histopathology of foetus and placenta Immunofluorescent Antibody test of Toxoplasma antigen in placenta PCR Serology

Answer 312

``` Biosecurity: - Control cat population - Control rodents - Secure feed stores to prevent access Vaccination: - Toxovax = live attenuated strain, undergoes limited multiplication in host - Given at least 3 weeks prior to tupping - Not in pregnant animals - Booster as data sheets ```

Answer 313

Particularly immunosuppressed people and pregnant women | From undercooked meat, raw sheep milk, cat faeces, lambing

Answer 314

Sources of infection: - Apparently, healthy carrier sheep (e.g. bought in sheep) - birds, rodents, wildlife contaminating feed etc Outbreaks of abortion in last 1/3 pregnancy (can be abortion storms) Ewes often systemically ill: metritis following abortion Diagnosis based on isolation of organism from aborted material: - foetus and placenta - foetal stomach

Answer 315

``` Reduce spread: - Isolate aborting ewes - Burn infected material - Clean and disinfect pens Consider antibiotic treatment: - Sick sheep - Whole flock - Long Acting oxytetracycline, repeat 7-10day - NSAIDs Consider source of infection: - Sheep, biosecurity measures (closed flock, don't mix bought in sheep until after lambing) - Other animals e.g. wildlife reduce exposure - Access to feeds, lambing sheds ```

Answer 316

``` Abortion in last 6 weeks or weak born lambs, 1-4 weeks post infection Ewes may become ill with metritis Sources of infection: - carrier sheep - contaminated feed or water - aborted material - birds Can occur in storms Very contagious in environment Diagnosis: - smear and culture of placenta, fatal stomach and liver Control: - isolate aborting ewes and dispose of material - broad spectrum antibiotics - no vaccine in UK - risk often to bought in replacements - zoonotic! ```

Answer 317

``` Pestivirus closely related to bovine BVDV and CSF Infection introduced and maintained in flock by PI animals Pregnant <60d: - fetal death (barren) - mummification - abortion - still birth - 50% survive and are normal Pregnant 60-85d: - foetal death - abortion - still birth - hairy shakers: encephalitis (cerebral hypoplasia, ataxia, hypermetria), long limbs - small weak lambs - PI (can look normal) Pregnant >85d: - normal Ab positive lambs Non pregnant: no clinical signs What happens with pregnant ewes depends on: - stage of pregnancy - immuno-competence of foetus - strain and dose of virus ```

Answer 318

Diagnosis: - clinical signs of hairy shakers - PM lambs (histology, virus isolation) - Ab serology from ewes - Ag PCR from ewes - test suspect PIs from 3mo for Ag Control: - if bought in and diagnosed, don't breed from entire lamb crop and try to identify PI from the bought in sheep and slaughter her - if endemic, test whole flock for PI and cull? - biosecurity: closed flock, test bought in for PIs (virus PCR on serum)

Answer 319

Zoonotic (fever, vom diarrhoea, headache) Infects many species including arthropods, sheep and goats Spread in infected placenta/foetus/fluids/milk and urine and faeces, dust Very resistant in environment Infection via direct contact and inhalation Abortion storms, still births, poor lambs Diagnosis: - Serology, bacteriology and histopathology of foetus Control: - Isolation of infected animals - Burn contaminated material - Oxytetracycline injectable - Pasteurisation of milk

Answer 320

``` Bunyaviridae family Transmitted by Culicoides Signs in cattle: - mild disease - diarrhoea, fever, milk drop of 50% - recover quickly in 2-5d Sheep: - no apparent clinical signs - increased return to service - increased barren ewe rate Congenital malformations: - may be born alive or dead - may be >25% abnormal births - bent limbs and fixed joints - twisted neck or spine - domed head - short lower jaw - live 'dummy' - blindness - wobbly - inability to suck - fitting Small window of infection of foetus in sheep: 26-56 days Control: - vaccine but not always available - delay breeding to midge season finished? ```

Answer 321

Not notifiable | They will send off samples which are tested for free to check for the virus

Answer 322

``` Isolate ewe Remove contaminated material and burn Clean and disinfect pens Beware zoonotic risk Take appropriate samples: - foetus and placenta - foetal stomach, foetal fluids, placenta - if foetus and placenta not available, blood sample and vaginal swab from ewe ```

Answer 323

Mannheimia haemolytica | Bibersteinia trehalosi

Answer 324

Vertical: - = mother to offspring in utero Pseudo-vertical: - parten to offspring at birth, from infected birth tissues Horizontal: - adult to adult/lamb from infected sheep Contaminated land: - where infected sheep used to live (decades before) Iatrogenic: - needle contamination

Answer 325

``` ARR - resistance AHQ - resistance with VRQ ARG - susceptibility ARH - susceptibility with VRQ VRQ - susceptibility ```

Answer 326

Polymorphisms known at 17 codons | Disease linkage to scrapie at codons 136, 154 and 171

Answer 327

Scrapie-free farms: - Voluntary scheme, aimed to protect currently uninfected farms by increasing level of genetic resistance - lambs and sheep genotyped at no cost, under condition that those bearing VRQ allele will be culled Scrapie-infected farms: - Compulsory scheme known as the Compulsory Scrapie Flocks Scheme (CSFS) - Compulsory slaughter of entire flock (with later restocking) OR compulsory genotyping of entire flock, followed by culling of all animals encoding VRQ (except ARR/VRQ) Goats also get scrapie (and BSE): TSE control is by whole herd killing, as there is not significant genetic resistance

Answer 328

Characterised by: - unusual distribution of PrPSc in brain - High age: mean 6.5 years - mostly single cases in flocks

Answer 329

Clostridium perfringens/tetani vaccine

Answer 330

Chronic pyelonephritis

Answer 331

Chronic fasciolosis associated with Fasciola hepatica Liver is reduced in size and cirrhotic with enlarged and thickened bile ducts (anaemia + winter) - johnes less likely?

Answer 332

Nematodirus battus

Answer 333

Dictyocaulus filaria

Answer 334

Haemonchus contortus (also if lambs which are found dead, or lethargic, weak and pale mm but no scour

Answer 335

Echinococcus granulosus and/or Cysticercus tenuicollis

Answer 336

Anthelmintic resistant Teladorsagia circumcincta