Lecture 5

the different strategies for mechanical ventilation are based on the _ of the animal and the _ conditions

age, weather

animal houses need adequate ventilation to remove _, _, _ like _ and _ along with _, and _

heat, moisture, gases, CO2, NH3, odors, dust

different ventilation modes have _ and _ effects

seasonal, age

if outside temperature is cooler (less than) the inside temperature, heat is _ from the poultry house structure

lost

if outside temperature is _(_than) the inside temperature, heat is lost from the poultry house structure

cooler, less

if outside temperature is _ (_ than) the inside temperature, heat is added to the poultry house structure

warmer, more

if outside temperature is warmer (more than) the inside temperature, heat is _ to the poultry house structure

added

the heat or energy balance of the building is determined by the _ and how much heat/energy the building can absorb from radiation, or its _

size and number of animals in the building, insulation

larger animals and more quantity of animals generate _ heat

more

the _ is a measure of insulation

thermoresistant value r

the thermoresistant value r is a measure of _

insulation

the thermoresistant value r is a measure of insulation

the r value for the wall of the poultry house, for example, is _

20-25

the thermoresistant value r is a measure of insulation

the r value for the standard poultry house as a whole, for example, is _

19-20

_ conditions determine how much heat is gained or lost by the poultry house

outside

ventilation rate can be evaluated based on _ or _, which looks at the balance between outside temperature conditions and the number/size of animals inside and how much heat they generate. allows us to understand ventilation needed to maintain ideal _ for animals.

temperature, heat balance, temperature

ventilation rate based on moisture or moisture balance helps us understand the ventilation required to maintain ideal _ level for animals, with is _

moisture, 50-60% humidity

poultry house managers are looking to use the _ amount of ventilation needed to maintain ideal environmental conditions

minimum

to find moisture balance when evaluating ventilation, the _ level is compared to the _ level of humidity/moisture

outside, inside

moisture can result from a combination of _ moisture generation and _ and _ generation from _

animal, CO2, H2O, propane gas burned for heaters

ventilation rate evaluated for _ or _ looks to bring in enough fresh air to dilute or reduce ammonia concentration inside the house.

ammonia, ammonia balance

levels of _ are of primary concern in terms of air quality in poultry, as this is a very irritating gas in high concentrations that can lead to eye and respiratory tract irritation

ammonia

levels of ammonia are of primary concern in terms of air quality in poultry, as this is a very irritating gas in high concentrations that can lead to _ and _ irritation

eye, respiratory tract

ammonia levels greater than _ start to impact human/animal health, causing eye watering and coughing, for example

25 ppm

ideal ammonia concentration is less than or equal to _

25 ppm

when ammonia reaches high concentration, like _, the corneas of chicks can be burnt, which causes blindness

100-150 ppm

ventilation based on temperature or heat balance as the following flow:

cool air enters _

air picks up _ as travels through house

this air leaves out the _ in the _ of the wall on the _ side

sidewall inlets, heat, fans, middle, opposite

ventilation based on moisture or moisture balance as the following flow:

cool air enters _

air picks up _ from the _ and _ levels as travels through house

this air leaves out the _ in the _ of the wall on the _ side

sidewall inlets, moisture, floor, animal, fans, middle, opposite

ventilation based on ammonia or ammonia balance as the following flow:

cool air enters _

air picks up _ from the _ level as travels through house

this air leaves out the _ in the _ of the wall on the _ side

sidewall inlets, ammonia, floor, fans, middle, opposite

the structure and ventilation of the building helps to determine _ ventilation to maintain ideal temperature, moisture level, and low ammonia levels

baseline

determination of ventilation rates is done by the computer system using equations that look at the _ of the bird, _ of birds, _ characteristics of the building, and _ of different parameters like _, _, and _

age, number, structural/insulation, level, temperature, moisture, ammonia

in the _, less ventilation is needed to maintain ideal temperature, but more ventilation is needed to maintain moisture levels

winter

in the winter, less ventilation is needed to maintain ideal _, but more ventilation is needed to maintain _ levels

temperature, moisture

_ through _ is used to make up for heat loss due to the level of ventilation needed for moisture control in winter

supplemental heat, heaters

supplemental heat through heaters is used to make up for heat loss due to the level of ventilation needed for _ control in winter

moisture

the higher ventilation requirement for moisture removal in winter means that more _ needs to be brought into the house to remove moisture, which causes the house to lose a lot of heat.

this is why supplemental heat in the form of heaters is used in winter

cool air

the minimum ventilation needed to maintain ideal moisture conditions in the cold is _ than the minimum ventilation needed to maintain ideal temperature in cold conditions

higher

birds generate _ heat as they get older, which means their ventilation rates required for heat loss _ as they get older

more, increase

the temperature at which both levels of _ control and _control meet is the critical temperature point for the bird, which _ with age

temperature, moisture, increases

if the outside temperature is _ the critical temperature point for the bird, supplemental heat is needed to maintain ideal temperature with proper ventilation for ideal humidity

below

if the outside temperature is _ the critical temperature point for the bird, a lot of ventilation is needed to maintain ideal temperature with cooling and maintain ideal humidity levels

above

the _ is the minimum amount of air movement needed for the animal to maintain ideal housing conditions (temperature, moisture, ammonia)

minimum ventilation rate Vmin

the maximum ventilation rate Vmax needed to maintain thermoneutral zone in hot conditions, like summer, is _

60-100 ACH

60 ACH means that within a 1 hour period, all of the air in the house is replaced _ times, or 1 time per _

60, minute

ACH means _ and is equal to the ventilation rate/volume

air change per hour

ACH means air change per hour and is equal to the _

ventilation rate/volume

Vmax air speed is _

500-750 feet per minute

tunnel ventilation with higher air speed combined with the wind chill effect drastically _ heat loss from animal

increases

moisture control is tied closely to _ control, meaning that if ventilation can control the moisture levels, it likely also controls _ levels well as well.

ammonia, ammonia

if ventilating for ideal humidity at 50%, the _ should also be able to stay under _

ammonia, 25 ppm

the balance of ventilation in the winter is to _ ventilation to _ heat loss, but not burn too much fuel for heaters to _ overall cost.

can’t have too low ventilation because _ and _ levels will rise and affect performance

decrease, decrease, increase, moisture, ammonia

fan flow rate _ with increasing static pressure

decreases

fan flow rate decreases with _ static pressure

increasing

_ is used to control air speed/flow pattern inside the building

static pressure

ideal air speed for ventilation is _

1000-1200 ft/min

low static pressure means that fan flow rate is _

high

high static pressure means that fan slow rate is _ because…, so _ air is removed by the fan

low, fan works hard against static pressure, less

_ affects the amount of air that can be removed by the ventilation fans

static pressure

typical ventilation fans are _ in size and have _ or _ blades

large, cast iron, aluminum

the _ of the fan provides an exit point for wind, that way cross winds do not negatively affect fan performance

discharge cone

there is variation in fan flow rate even between fans of the same diameter due to ….

how well the fan is maintained

if fan belts are not replaced about every 2 months, fan performance can _ by _

decrease, 20-30%

the stage of ventilation that is used (for example out of 6 ventilation stages) or, in other words, the number of fans that are turned on and for how long, depends on _ and _

outside conditions, animal age

the UD poultry houses have _ fan for the different stages of ventilation. our controller is used to control the run time of the different stages

1

most houses have an average of _ fans, with larger poultry operations having _ fans

8, 12-14

the stages of ventilation are as follows:

V1 = _, for example _ fans

V2 = _, for example _ fans

V3 = _, for example _ fans

V4 = _, for example _ fans

V5 = _, for example _ fans

V6 = for example _ fans

VMin, 2, 1.4V1, 3, 1.4V2, 4, 1.4V3, 6, 2V4, 12, 14

the _ functions by having outside air go through here first, reducing the heat of the air as it enters the building

evaporative cooling pad

broiler houses that can _ ventilate must also be able to operate in two other modes of ventilation:

minimum or traditional ventilation

transitional ventilation

tunnel

broiler houses that can tunnel ventilate must also be able to operate in two other modes of ventilation:

_ ventilation

_ ventilation

minimum or traditional, transitional

the equipment of a tunnel ventilated broiler house includes:

_, _, _, and _

evaporative cooling pads over tunnel inlets, sidewall inlets, tunnel fans, and minimum ventilation sidewall fan

sidewall inlets run along the _ of the wall in a pattern that follows _ feet of inlet, _ feet of space, and another _ feet of inlet. in other words, there is an average of 1 inlet per every _ feet

top, 4, 4, 4, 8-12

for minimum ventilation conditions, tunnel ventilated broiler houses typically use _ tunnel sidewall fans, one at the _, and one at the _ end

2, evaporative pad, opposite

the minimum ventilation fan is typically the _

last sidewall fan on the end wall

during the winter, minimum ventilation sidewall fans are used to remove _, _, and _. they simply allow for basic _

dust, ammonia, moisture, air movement

during winter in the tunnel ventilated poultry house system, only the _ and _ are used. _ are not used, and _ are turned off or shuttered

sidewall inlets, minimum ventilation sidewall fans, evaporative cooling pads, tunnel fans

during colder months with the tunnel ventilated broiler house, pressure is kept steady at _ inch column. this provides good air mixing and _ enough air speed that cold draft is not created or cold spots on the floor

0\.08-1, low

minimum ventilation is used under the following conditions:

when there is _ weather

when the birds are very _, which is when they _ generate a lot of heat

when outside air is _ than inside optimum or thermoneutral zone

in order to provide _

cold, young, do not, cooler, supplemental heat

the purpose of minimum ventilation is to:

ventilate for _

remove _ to keep litter _

and conserve house _

good air quality (less ammonia), moisture build-up, dry, heat

equipment used for minimum ventilation includes:

_

_

_ controlled by _

a _ that overrides the timer

and inlets operated by a _ controller

sidewall fans, sidewall inlets, fans, timer, thermostat, static pressure

an example fan runs is having the fans run a total of _ out of every _. this is equivalent to running about 10% of the time

30 seconds, 5 minutes

most fans are controlled by a timer, as they do not run _

continuously

fans do not run continuously because this could…

bring in too much cool air

inlets are operated by a static pressure controller to maintain the _

air flow pattern

the minimum ventilation requirement per bird gradually _ with age

increases

typical per bird rates for minimum ventilation

week 1 (days 1-7) cfm/bird = _

week 2 (days 8-14) cfm/bird = _

week 3 (days 15-21) cfm/bird = _

week 4 (days 22-28) cfm/bird = _

week 5 (days 29-35) cfm/bird = _

week 6 (days 36-42) cfm/bird = _

week 7 (days 43-49) cfm/bird = _

week 8 (days 50-56) cfm/bird = _

after 8/9 weeks, cfm/bird = _

0\.1, 0.25, 0.35, 0.50, 0.65, 0.70, 0.80, 0.90, 0.1

ideal air flow for minimum ventilation is that cool air enters the _ and picks up _ as it rises to the ceiling. this way the air that hits the animal level is _to be the temperature of the house

sidewall, heat, preheated

minimum ventilation allows for litter _ control, _ control, and energy _

moisture, ammonia, conservation

energy is conserved with ventilation by:

improving structure _ and reducing _ from ceiling, walls, doors, and fans

insulation, heat loss

energy is conserved with ventilation by:

maintaining proper _ and reducing _ from structures

this allows for proper _ and even _ distribution

static pressure, infiltration, air mixing, temperature

energy is conserved with ventilation by:

using the attic vent to harvest _

this should be controlled by the control and used when _ is needed

solar energy, heating

tunnel ventilation is used when there is:

_ weather

for _ (usually _) and _ birds

when the outside temperature is _ than the set point

hot, older, fully feathered, larger, greater

bird’s production of _ is the greatest problem in the poultry house

heat

in the beginning of their life, chicks have a thermoneutral zone of about _ F

90

by weeks of age, the ideal temperature of birds is around _ F

this is because as birds age, their thermoneutral zone _ by _F

65-70, decreases, 5

increased air movement = _ cooling

increased

the purpose of tunnel ventilation is to:

_ in house heat build up

flow _ onto birds

produce _

exhaust, high velocity air, wind chill effect

equipment used for tunnel ventilation incudes:

_

inlets operated by a _

_

fans controlled by _

_ fully closed

may add _

tunnel inlets/curtains, static pressure controller, tunnel fans, temperature/wind chill, sidewall inlets, evaporative cooling pad

_ fans are the large fans located at the opposite end of the tunnel ventilation poultry house from the evaporative cooling pad

tunnel

sidewall inlets are fully closed for tunnel ventilation because they will _ at the _ level if open

reduce air speed, animal

the evaporative cooling pad is used to reduce _ or improve _, if desired

air temperature, wind chill effect

cold stress causes an _ in feed conversion

increase