PP2

Question 1

Acids; mechanism of action, properties and using:

Answer 1

MA: oxidation, dehydration, destruction of enzymatic system, disruption of cell membrane permeability, denuaturation of proteins
P: strongest disinfectant, inorganic or organic, effective against specially G+, also G-, viruses and fungi
U: inorganic (strong, corrosive effect) - HCL for disinfection of skin, sulphuric acid - cresol-sulphuric mix, nitric acid - food industry + milking equipment, phosphoric acid - manure and soil, organic - peracetic acid - bactericidalsporicidal and fungicidal effect + mycobacteria and algae

Question 2

What usntable disinfectants do you know? Application?

Answer 2

NaOH - unstable during storage, spray
Peracetic acid - spraying, aerosol or dipping
Chlorinated lime - powder
Aldehydes - formalin/formaldehyde, liquid, vapour or gaseous

Question 3

Peracetic acid mechanism of action, properties and using:

Answer 3

MA: oxidation, dehydration, destruction of enzymatic system
P: bactericidal, virucidal, sporicidal, fungicidal
U: spraying or aerosol, dipping solution

Question 4

Chlorine compounds mechanism of action, properties and using:

Answer 4

MA: oxidation of proteins, fats, effect on enzymatic systems
Markedly reduced at presence of organic matter (form trihalomethanes)
P: Bactericidal and virucidal
U: sodium hypochlorite (liquid, dairy industry for farm buildings), chlorinated lime (powder)

Question 5

How is microbial control of disinfection?

Answer 5

Assess the effectiveness
Direct participation in the conduct of disinfection
Quality of mechanical cleaning
Character of the environment
The way of using disinfectant
Indirect control according to protocol

Question 6

Which indicator of microorganisms is used for effectiveness of disinfection in animal production?

Answer 6

Coliforms

Question 7

Methods for evaluation of drinking water:

Answer 7

Physical evaluation
Chemical evaluation
Microbiological evaluation

Question 8

What are the lifecycles of insects?

Answer 8

1. Hemimetabolous metamorphism - tick, mite - incomplete
2. Holometabolous metamorphism - complete, larva is totally different than adult
3. Ametabolous - no metamorphism

Question 9

Organophosphate insecticides mechanism of action, properties and using:

Answer 9

MA: inhibit neuromuscular enzymes, disrupt brain from sending neurotransmitters, block acetylcholine
P: Physical and chemical, octanol/water partition coefficient, hydrolysis and binding to proteins
U: wide application in agriculture, residental landscaping, pest control programs

Question 10

What is pre-baiting and when is it used?

Answer 10

Placement of non-poisoned baits, to create a bait acceptance. 2-3 days.

Question 11

Specify residual affects of rodenticides:

Answer 11

Resistance development
- against anticoagulant, or develop from generation to generation,
Behavioural: neophybia (bait shyness)

Insecticides:
resistance by genetic mutation and selection

Question 12

Mechanism of action of synthetic pyrethroids on insects, properties and using:

Answer 12

MA: sodium channel modulators, interfere signal propagation, hyperexcitation and tremors followed by paralysis
P: insects are 2250 times more sensitive than mammals
U: households, toxic to fish and bees

Question 13

How do we classify insecticides?

Answer 13

According to effect on lifecycle
- ovicides, larvicides, adulticides
According to entry into organism
- contact, stomach, respiratory
According to mode of action
- systemic or residual
According to origin
- plant derived, synthetic

Question 14

Define types of disinfection:

Answer 14

Preventative
Focal:
- continuous: several times/days, during infection
- final: after infection

Question 15

Name two ways of disinfection:

Answer 15

Chemical and physical

Question 16

Control of disinfectant can be:

Answer 16

Direct: quality of cleaning, character of the environment and use of disinfectant
Indirect: protocol
Chemical control
MO control - total bacterial count

Question 17

Name air gases that can act as pollutants:

Answer 17

CO2 - indicator of general hygiene and ventilation, max 3000 ppm (0.3%)
NH3 - decomposition of organic substances (uric acid and urea), max 25 ppm
H2S - anaerobic decomposition, max 10 ppm

Question 18

Chemical parameters in drinking water and limits:

Answer 18

pH: 6.5-9.5
Ammonia and ammonium ions: max 0.5 mg/L
Nitrites: 0.1 mg/L
Methemoglobin: 500 mg/L adults, 1-10 mg/L young
Nitrates: 50 mg/L, 15 mg/L youngs
Phosphates: 1 mg/L
Iron: 0.2 mg/L
Active chlorine: 0.05-0.3 mg/L

Question 19

Important insects for insecticides to eliminate:

Answer 19

Cockroaches
Housefly
Mosquitoes
Fleas
Lice
Ticks

Question 20

Groups of synthetic insecticides:

Answer 20

Synthetic pyrethroids
Organophosphates
Carbamate insecticides
Neonicotinoid insecticides
Inorganic synthetic insecticides
Chlorinated hydrocarbons
Fumigants

Question 21

Mechanism of effect of organophosphates:

Answer 21

Kill a wide variety of animals and act as stomach, contact and respiratory poisons
Degraded rapidly, short residual effects
Systemic - cholinesterase inhibitors - overstimulation of nervous system and death

Question 22

Mechanism of action of carbamates insecticides:

Answer 22

Stomach and contact poisons
Cholinesterase inhibitors
Longer lasting residual effect

Question 23

Disinfection of excrement and soil use:

Answer 23

Lime 3%
Peracetic acid 0.3-0.5%
Phosphoric acid 1-1.5%

Question 24

Objects of disinfection:

Answer 24

Instruments
Equipment
Working clothes
Footwear
Air
Water
Excrements
Soil
Vehicles

Question 25

Groups of synthetic insecticides:

Answer 25

Pyrethroids Organophosphates Neonicotinoid Carbamates Chlorinated hydrocarbons Fumigants Inorganic synthetic insecticides

Question 26

Objects of sanitation:

Answer 26

Animal housings Food establishments Food processing facilities Hospitals and clinics Public spaces Human dwellings Water