PMVPH

Question 1

What is a risk analysis and what are its aims

Answer 1

Structures, transparent approach to deal with undesired events that may happen.
Aims to:
> Identify hazard
> Hazard characteristics
> Exposure assessment 
> Risk characterisation

Question 2

what is COSHH and what are some of its points

Answer 2

control of substances hazardous to health in the workplace.

• vaccination and worming programes
• Avoid contamination of drinking water
• Good waste management
• Use of PPE
• Control pests/vermin
• Educate workers/visitors
• Implement herd health plan

Question 3

What are the most common non-food borne zoonoses control in food producing animals

Answer 3

> Hydatid cyst - prevalence in wales
Influenza virus - When theres an outbreak, all pultry within 3km radius are culled and a surveillance area of 10km, where all birds are tested and restriction on movement imposed
E.coli
Cryptospiridium - usually self limiting, however can be life threatening in vulnerable populations.

Question 4

What is the definition of monitoring

Answer 4

Continuous effort to collect data to detect changes or trends (e.g milk yield) in order to make informed decisions. Often used to assess effectiveness of control program or demonstrate freedom from infection

Question 5

Define surveillance

Answer 5

Special case of monitoring. Data us used to assess a status in response to a pre-defined threshold, once threshold is reached action is taken E.g SCC. Expensive

Question 6

Describe the differences between passive and active monitoring

Answer 6

Passive: Relies on waiting and cases being reported. dependent on motivation and awareness, ie farmer reports cases of mastitis however increased chance of bias because reporting mastitis may decrease the premium he’s payed, therefore high amount of EXTERNAL VALIDITY

Active: Actively seeking results by conducting your own tests and surveys, very expensive but has high amount of INTERNAL VALIDITY

Question 7

describe the concept of surveillance

Answer 7

> Case clearly defined
Detection via notification (passive) or screening (active)
Diagnostic tests - Sensitivity (detect true disease) & specificity ( detect those without disease)
sampling - Must have minimal bias and sample must accurately represent population

Question 8

What is a ‘hazard’ and what is a ‘risk’

Answer 8

Hazard - An agent/substance/action that has the potential to cause and undesired effect. E.g E.coli 0157 from faecal contamination or poor quality silage causes PH increase which increases chances of listeria.

Risk - The probability of an undesired event and the consequences of the undesired effect

Question 9

Describe the difference between risk assessment qnd risk management at farm level

Answer 9

RISK ASSESSMENT at farm level is to identify and relevant hazards, prioritise them and evaluate risk to management strategies. where as RISK MANAGEMENT is to reduce and prevent the risk related to hazard

Question 10

What are sources of pre harvest food safety

Answer 10

> Animal - E.coli 0157 (cattle are largest reservoir) & TB (intervals of testing determined by location)

> Feed - salmonella (active surveillance in poultry and passive in other species) & listeria ( increased PH in poor quality silage causes listeria growth) can also be contaminated with pesticides & fungicides.

> Environment - Campylobacter (most common zoonosis in EU, 73% poultry tested positive, gold standard bio security only reduces 1/3 of cases, is it worth it ?)

> Wildlife - coxiella burnetti (Qfever), TB and campylobacter

> Personnel - Staphylococcus aureus and salmonella

Question 11

What are the 4 points for the risk management strategy

Answer 11

1. Risk transfer - Insurance company take liability
2. Risk avoidance - not performing hazardous activity e.g from production farm converting to petting farm
3. Risk mitigation - reduction of negative consequences, set target levels
4. Risk acceptance - If below set target do nothing

Question 12

Define obesity

Answer 12

Excess body fat is sufficient to result in impairment of health and organ function

Question 13

What are the consequences of being obese ?

Answer 13

> General anesthetic risk increased (especiall post op_
In cats 3.7x more likely diabetes mellitus and increased risk of urethral obstruction, hepatic lipidosis if animal becomes ill and loses excess weight
In dogs increases risk of pancreatitis
increased risk of upper airway resistance and decreased function residual capacity
increased stress at joints causes decreased mobility and increased post op complications

Question 14

What are contributing factors to becoming obese

Answer 14

> Imbalance between intake and expenditure
Client related - Ad lib feeding and multiple family members feeding
Reproductive status - neutering reduces energy requirements by 30% but this inst reflects in the diet
Lifestyle - reduced activity and feeding of scraps
Age - Increased fat with age and decreased lean muscle. Fat has about 25% energy requirements of lean muscle therefore needs to be reflected in the diet
Breed predisposition - Pug, golden retriever, cocker spaniel, basset hound, Labrador and dachshunds

Question 15

What is targeted surveillance

Answer 15

Go out actively looking for samples. commonly done when following up a carcase submission and is done free of charge. Done with:
>Notifiable diseases
>Zoonotic disease
>Novel disease
>Antimicrobial resitance
>Import testing

Question 16

Describe the 6 step process to flock/herd investigation

Answer 16

1. Define the problem - Is it disease related or poor production. herd problem or individual?
2. History - General (time of the year, stage in production), Clinical signs, medicine records, management and any predisposing factors
3. Distance exam - Includes environment (e.g lack of pasture or housing), stocking density and the animals (respiratory rates, postures, abnormal sings)
4. Individual exams - Careful selection of the sickest animals. Basic exam e.g BCS, temp, heart rate, mucous membranes. May want to PM a sick individual
5. Furthur diagnostics - Biochem often unrewarding (chronic cases could be in compensatory phases). Useful tests include F.e.c, trace elements, nutritional analysis and post mortem
6. Data analysis & decision making

Question 17

What is poor thrift and what is the result of it

Answer 17

characterized by: 
> Insufficient weight gain
> Inappropriate weight loss
> Failure to achieve target weight
> Very low BCS

Results in increased outputs and decreased profits

Question 18

What are the effects of poor thrift in an adults dairy cow during mating, early/late pregnancy and during lactation

Answer 18

Mating: Increases the length of anoestrus, decreases conception and ovulation rates. This leads to increased costs due to repeat services and also amount of days in lactation decreases.

Early pregnancy - Decreases placental development
Late pregnancy - Increases the risk of metabolic disorders

Lactation - Decrease in milk production

Question 19

What are the steps involved in investigating poor thrift

Answer 19

Step 1. a) Define the problem - Done via farm records, increased time to slaughter.
b) Refine problem - Is it the entire heard or a subgroup? Is nutrition adequate? - If no then could be underfeeding or trace element deficiency, if yes then could be a maldigestion/malabsorption problem.

Step 2. History - Reproductive rate, time of calving, previous trace element deficiency ? worming regime?

Step 3. Environment exam - Pasture and feed availability

Step 4. a) Distance exam - Variations in size and weight, scouring?, coughing?, lameness? or pruritus

b) Individual exam - Basic exam, mucous membranes, temp (38.6), BCS and lameness.
c) PM - Chronic cases with no signs of improvement may be euthanised for PM. can collect liver sample (Trace elements), examine for liver fluke, worms in GIT and examine lungs

Step 5 - Diagnostic tests - F.e.c, blood tests ( trace elements) and food analysis

Step 6 - Data analysis - If any TE’s are marginal will they respond to supplements?

Step 7 - write report

Question 20

What is the difference between primary and secondary trace element deficiency and when should TE deficiency be suspected they be suspected

Answer 20

Primary - Soil and plant deficiency in CO, Se, I and Cu.
Secondary - Lack of absorption in animal (e.g Cu binds to S and Fe in the rumen)

Should consider TE deficiency when:
> more than one animal effected
> Poor thrift
> Gait abnormalities (sway back - Cu or white muscle disease - Se)
> Goitre

Question 21

What Factors effects TE deficiencies

Answer 21

> Uneven distribution in the pasture
> Uneven distribution withing the plant
> Seasonal changes
> Selective grazing 
> Contamination with soil ( can cause and increase or decrease dependent on taking up by other elements, e.g Sulphur can bind to Cu)
> Animals ability to absorb varies

Question 22

What does Cobalt deficiency cause

Answer 22

Co is a component of vitamin B12. Deficiency leads to a decrease in glucose ( because its a coenzyme involved in propianate). Often presents with weaned lambs with poor thrift. Sheep are more susceptible ! often associated with concurrent parasitism!

Question 23

What does Selenium deficiency cause

Answer 23

Causes white muscle disease effecting lambs usually of the age of 2-6 weeks.
- Subclinical disease will cause decreased growth rates and embryonic deaths. Plasma glutathione peroxidase levels often used as a marker for selenium levels

Question 24

What does copper deficiency cause

Answer 24

Copper is essential for many enzymes including those involved in myelin formation, pigmentation, elastin/collagen synthesis and iron release during RBC production.
Clinical signs include - Poor thrift, Sway back (cant walk due to decreased myelin production) and anaemia.
Liver has high amount of stores, therefore need lots of samples from a number animals.
More of a problem in cattle, however the Texel is susceptible

Question 25

What does Iodine deficiency cause

Answer 25

Needed for thyroid hormone production. Clinical cases will give birth lambs with goitre. Adults seem to deal with fluctuation of iodine as they have adequate reserves. Blood and liver tests can be conducted at the abattoir.

Question 26

How can trace elements be supplemented

Answer 26

> Oral dosing or in feed
Injection
Slow release rumen capsule
Addition of fertiliser ( do a fertiliser test to test)

Question 27

Describe the investigation steps involved in sudden death of farm animals

Answer 27

Step 1. Define the problem - is it sudden death or has the farmer missed it ?

Step 2. History - Number/groups/fields effected. Was there a progression of signs? worming and vaccination history. management changes - recent treatment, changed fields/food or any unusual weather.

Step 3. a) Toxicity? or any led battery in the fields
b) Distance exam - Looking for clear/sick individuals

Step 4. Post mortem - Highly recommended - the quicker sent the better the diagnosis rate

Step 5. Furthur diagnostics

Step 6. Data analysis/decision making - Quick/decisive, management changes and control programme

Question 28

What are possible causes of sudden death on farm

Answer 28

> Infectious - Septicaemia, toxaemia/ anaemia (acute fasciolitosis). Flooding predisposes leptospirosis, High stocking density predisposes salmonellosis.

> Toxicity - Plant (oak, yew and oleander) & chemical

> Metabolic diseases - Hypomagnesemia - No effective tissue store for Mg, critical role in neuromuscular transmission. Also thiamine deficiency will cause cerebro-cortical necrosis.

Climatic - Lightening or hypothermia

Question 29

What are the SCOPS guidelines to parasitism

Answer 29

1. Work out a control strategy with the vet
2. Effective quarantine strategies to prevent resistant worm population
3. Test for Anthelmintic resistance
4. Administer anthelmentics effictively
5. Use anthelmintics only when necessary. Dependent on F.e.c
6. Select appropriate anthelmentic. Dont treat for two different helminths at once. E.g use a flukecide or a anthelmentic not one that covers both
7. Adopt strategies to preserve susceptible worms on farm
8. Reduce dependence on anthelmentics

Question 30

What is the cause of watery mouth in lambs and what is the treatment and how is it prevented

Answer 30

> Caused by E.coli colonisation of the gut of the newborn lamb
Treat with oral electrolyte therapy at a rate of 50ml/kg 4x a day & intramuscular penicillin
Prevention - Ensure adequate colostrum (50ml/kg in 2 hours) or maybe stomach tube warm yoghurt (30mls)

Question 31

What conditions cause hypothermia in lambs and how is it treated

Answer 31

> Linked to management issues. When the lamb reaches 37 degrees or less.
Ensure lambs are well fed, brown fat around kidney will only supply thermogenic heat for first 5 hours.
Primary hypothermia - Glucose in blood is sufficient but environment losses are to high.
Place in a warming box at 45 degrees until strong enough to swallow, then give colostrum. Cant place in a hot box if under 6 hours, will kill lamb. If over 6 hours, give 20ml of 40% glucose and 20mls of boiled water, inject into peritoneum.