Рефераты. Replacement Housing (Помещения для ремонтного молодняка)

continuous exchange of air, Table 7. Because the number of calves and young

heifers in a facility vary, design mechanical ventilation systems for a

range of stocking rates.

Calf housing (up to weaning)

Calves and young heifers are very susceptible to respiratory illness

and other diseases. Keep calves less than two months old in clean, dry,

draft-free facilities with adequate space, bedding and fresh air. Separate

calves to reduce disease transfer from nose-to-nose contact. Separate calf

groups from older animals to minimize exposure to disease organisms. Keep

calves in individual pens in an enclosed building or individual hutches

until weaning. After weaning they can be moved to small group pens.

Hutches in Cold Housing

Calf hutches have proven to be an excellent way to house calves. Only

one calf occupies each hutch. Typical hutches are 4'x8'x 4'. Fig 2

illustrates plywood construction. Leave one end of the hutch open and

provide a wire fence enclosure so the calf can move outside. Optional

tethers can be used where predators are not a problem. Seal tightly all

other sections of the hutch, except for the front and bottom, to reduce the

wind blowing through the hutch in winter. During summer, the rear of the

hutch can be blocked up 6" to allow for cross ventilation or design an

opening in the rear of the hutch with a tight fitting door.

There are also a variety of prefabricated plastic/fiberglass hutches on

the market. Hutches made of a translucent material require shade in summer.

Summer shade reduces heat stress on all types of hutches. Provide enough

shade to allow hutches to be moved.

Hutch management

Face hutch fronts south or east to provide draft protection during

winter and sun exposure during the day. Provide enough hutches to allow a

minimum of two weeks resting period after a calf is removed. Locate hutches

on a well drained area. Crushed rock or sand base provide a solid base for

bedding and lessen the possibility the hutch will freeze to the ground in

winter. After removing the calf, move the hutch to a clean site to break

disease cycles. Use enough bedding to keep calves clean and dry and to

insulate calves from the ground. To provide operator comfort, hutches may

be placed inside a well ventilated shed or structure, in effect providing a

cold housing environment in winter and shade in the summer, Fig 3.

Individual Pen in Cold Housing

Individual calf pens, Fig 4, can be used inside a cold housing

building. Pens are typically 4'x7' and removable. They provide isolation

for each calf. Solid partitions between pens and beyond the front of the

pen prevent nose-to-nose contact. A hover or cover on the back half of the

pen gives the calf additional protection in especially drafty locations.

Pens use building space more efficiently than do calf hutches, although

increasing animal density increases ventilation requirements. Place pens on

a crushed rock base or concrete floor to provide a base for bedding.

Individual pens require the same type of management as calf hutches.

Individual Stall in Warm Housing

Use individual 2'x4' stalls only in warm housing. This system requires

the least space per calf, but must be used in insulated, environmentally

controlled buildings with mechanical ventilation and supplemental heat.

Drafts, which occur in elevated stalls with open floors for drainage,

are detrimental to calf health. The incidence of calf disorders increases

in warm housing facilities after several years, due in part to warm

temperatures. Warm temperatures increase viability of disease organisms.

The facility must be adequately ventilated and sanitized on a routine

basis. Good ventilation, proper sanitation and careful observation of

calves are especially essential in warm housing systems to reduce disease.

Table 7. Dairy ventilating rates. Size the system based on total building


| |Ventilating rates |

|Animal |Cold |Mild |Hot |

| |Weather[8] |Weather |weather |

| |cfm/animal |

|Calves 0-2 months |15 |50 |100 |

|Heifers | | | |

|2-12 months |20 |60 |130 |

|12-24 months |30 |80 |180 |

|Cow 1,400 lb |50 |170 |470 |

|Room |Cfm |

|Milkroom |— |— |600 |

|Milking parlor, |— |100 |400 |

|cfm/stall | | | |

Transition housing (3-5 months)

Moving a newly weaned calf from an individual pen to a small group

environment is an abrupt change or transition. The combination of stresses

due to new social interactions with other calves, competition for feed and

water, and a new housing system can seriously affect calf growth and


Giving special consideration to the calf's environment can make this

transition less stressful as the calf adjusts to group living and learns to

compete. Monitor calves for adequate dry feed and water intake and make

sure calves are disease free before moving them into a group pen.

Provide transition housing for calves from weaning to 5 months of age.

Maintain small groups of 4-5 calves per group with a small range in size or

age (I month maximum). Provide well bedded pens that allow 25-30 ft2 of

resting space per calf. Have fresh water available at all times. Transition

housing should provide an environment similar to calf hutches only in a

group setting. Depending on herd size and the ability to observe an

individual calf, the maximum group size would be 20 calves.

Calf Shelter or Super Hutch

Portable shelters or super hutches can provide transition housing for

calves from cold housing. A super calf hutch is designed for up to six

calves, Fig 5. An optional paved lot and addition of a fenced area can be

used with the super hutches, Fig 6. Keep the shelter well bedded and

alternate the hutch site between groups of calves. In a pasture system the

super hutch can be rotated on the pasture, Fig 7. Waterers can be centrally

located or moved with the hutch site.

Transition Barn

For herds greater than 100 milking cows, a series of 10'x24' pens can

be used in a «transition barn» for calves up to six months old, Fig 8.

Capacity for this arrangement is six animals if the feed alley is scraped

and eight animals if the entire pen is bedded.

Transition barns commonly have a 3:12 single slope roof with no

insulation. The barns should open to the south or east to take advantage of

the sunlight. The eave in the back wall is open to aid in moisture control

in the winter. During summer remove fabric or other coverings on the back

and endwalls for natural ventilation. Extend both ends of the barn 4'

beyond the pen fronts to minimize wind effects at the corners of the barn

during cold weather. Locate waterers in the feed manger line to minimize

splashed water in the bedded area.

To minimize excessive drafts in long barns, attach plywood to gates and

hang fabric from the underside of the roof down to the gate between

alternate pens. During cold weather, place straw bales along the bottom

edge of the gates to stop drafts. Remove bales during warm weather.

Calf Barn

Calf barns combine individual pens, Fig 4, and transition group pens

for calves into one building design, Fig 9. A full open sidewall with

curtain provides cross ventilation in summer and draft protection in the

winter. The upper half of the building can be a pivot door or curtain for

draft protection in winter. The lower part of the wall can have removable

panels for better summer ventilation. Air movement through the building

should be sufficient to maintain inside temperature only slightly above

outside temperature in the winter and slightly below outside temperature in


Use solid partitions between calves to prevent nose to nose contact.

Wire fences on fronts and backs of pens allow better air circulation during

warm weather, but arrange pens to keep calves from contacting each other.

In winter, use solid pen backs to provide draft protection. Hovers may be

needed in winter. Choose or construct pens that are easily dismantled for

manure removal.

Heifer housing (6-24 months)

There are several options for housing heifers after transition housing.

Regardless of housing type, group animals according to a management plan

considering nutritional, health and reproductive needs of each group. At a

minimum, a logical break in grouping is a breeding age group and a bred

heifer group.

The primary functions of heifer housing are to:

> Minimize animal handling for treatment.

> Allow for animal breeding.

> Allow for animal observation.

Even though heifers can tolerate more stress as they grow older, they

still must be protected from wet conditions, drafts, and poor environment.

In open front housing, provide group pens of sufficient depth to protect

heifers from winter winds. Solid pen partitions help reduce drafts.

Freestall Housing

Young heifers are grouped in freestall housing with stalls sized

according to age or size of heifer, Table 4. Freestall housing requires

considerably less bedding than bedded pack housing. Frequent manure removal

is required (once or twice a week), unless floors are slotted. Frozen

manure can be a problem in cold barns, but is manageable.

There are several different layouts that can be used in freestall

housing. Each alternative is suited to particular feeding and manure

handling situations. Each alternative has adequate feedbunk space, Table 6.

Freestalls can be inside with outside lots for exercise and feeding. The

trend is having freestalls and feeding included under the building roof or

confined area. Outside exercise lots may still be provided for use during

periods of good weather.

Two-row freestall barn

Two-row freestall barns are typically used for up to 100 heifers, Fig

10. Freestall length for each group in Table 4 is sized to provide maximum

comfort for the size of animal in the group. Heifers are grouped in pens

around the perimeter of the building.

Manure is either scraped automatically, the alley is slotted or

flushed, because it is not possible to move animals during tractor

scraping. When animals have access to outside runs, tractor scraping can be

accomplished. Build an 8' alley when a feed cart is used. For drive-through

feeding, a 16'-18' alley is required.

Two-row graduated freestall barn

A two-row graduated freestall barn changes the length of the freestall

in the pen by placing the curb at an angle to the side of the building.

Stalls at one end of the building are shorter than at the other end of the

building. The alley floor is sloped toward the freestall where a grated

gutter is used to remove manure. The floor slope provides a self-cleaning

floor. Stalls are bedded with chopped bedding to allow movement of the

manure and bedding through the grate. Gravity gutter, flush gutter or barn

cleaner can be used to remove manure. Building temperatures must remain

above freezing most of the time to prevent frozen manure in gutters. This

type of building requires a controlled natural ventilation system.

Two-row gated freestall

A two-row gated freestall barn can provide good housing, Fig 11. Two

rows of freestalls along one side of a single bunk, all under roof,

provides flexibility in feeding system design. Depending on the particular

layout, feeding may be accomplished with a feed cart, mechanical bunk or

mobile scale mixer. In three-row barns, there is limited bunk space; when

feed is always available, competition for feed can be managed.

Two-row gated freestalls with optional outside exercise lots, can be

used in good weather, Fig 12. Manure in the gated freestall system is

easily removed by a tractor-mounted scraper. Cows are fenced in one alley

while the other alley is cleaned. When the feed bunk is located on the

south or east side in a cold barn, the bunk side of the building may be

left open. In warm housing, 4"-8" wide slats are an alternative for manure

handling. Slats could be placed over gravity channels to separate manure

from animals.

Drive-through gated freestall

Gated freestall barns can be expanded for larger herds by using a

common center feed alley. Stall rows are located on both sides of the feed

alley. Feeding can be accomplished with drive-through feeding alleys sized

for a feed wagon or feed cart.

Bedded Pack

Bedded pack housing is commonly used in conjunction with an outside

feeding and exercise area, Fig 13. However, there are advantages of roofing

the entire area including the scrape and feeding alley. Provide enough

space for each group of animals in the bedded resting area, Table 3. The

bedded area is roofed and provides a warm, draft-free resting surface.

Bedded pack barns are often sized to allow installation of a scrape alley

and freestalls at a later date.

Macadam or crushed rock surface can be used under the resting area pack. If

concrete is used, provide drainage by sloping to the scraped manure alley.

Add bedding to the upper end of the resting area pack as needed. Remove

manure and bedding as a solid 2-4 times a year. A substantial amount of

bedding is required to keep animals clean and dry.

Paved feeding alleys are typically scraped 2-3 times per week.

Extending the roof over this area reduces runoff. To provide for a system

with an outside lot, the feeding alley is extended away from the building

and is generally not roofed. Runoff must be controlled to prevent surface

water and groundwater contamination.

Outside drive-by feeding can be done or the feed platform can be roofed

under the same building when a scrape alley is used. The bunk can be roofed

separately when an outside lot is used. Bunk space may be limited in this

type of housing so feed should be available at all times to limit


Counter-sloped barn

The counter-sloped barn, a relatively low cost facility, is based on a

sloped resting and feeding floor separated by a tractor scraped alley, Fig

14. The resting floor and feeding floor are sloped 8% (l"/ft) toward the

center scrape alley and are self-cleaning. Size the resting area of the

pens to allow for a self-cleaning resting area. Table 3.

Runoff from uncovered alleys must be controlled to prevent stream and

groundwater pollution. The building can also be designed to be completely

under roof to control water entry. This system is not recommended for

heifers younger than six months or bred heifers during the last three

months of pregnancy because of bedding and the larger group sizes.

Optional outside lots

Optional outside lots can sometimes be incorporated into building

design when desired. Outside lots can help reduce manure accumulation in

the building, but must be cleaned and managed properly. Outside lots may be

of some benefit in reducing foot and leg problems in dry cows. Pasture is

sometimes used as part of the feed ration. Animal density is low to allow

the pasture to recover after grazing. Pasture can be rotated to provide

rest and recovery of vegetation. Pasture that is too heavily grazed becomes

a dirt lot over time and can cause problems when not managed properly.

Dirt exercise lots tend to have a high animal density and typically

have little or no vegetative cover. They become muddy in wet weather and

can cause environmental mastitis in heifers before they enter the milking

herd. Use dirt lots only when weather permits.

Concrete paved exercise lots can be incorporated into building designs

either as an exercise area or an integral part of the building design.

Runoff from lots must be controlled and handled as part of the manure

handling and storage system. Additional labor is required to scrape lots

and dispose of manure. Consider the cost of a runoff control system in the

total system cost. Also consider water quality issues in the overall design

of the housing option.

По мере того как подрастает ремонтный молодняк, изменяются его

потребности. Под этим подразумевается необходимые изменения в среде

обитания животного. Когда телки подрастают, они изолируются от других

животных для уменьшения риска заболевания. По мере того как телка растет,

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