- February, 2011
- January, 2011
- December, 2010
- November, 2010
- October, 2010
- September, 2010
- August, 2010
- July, 2010
- June, 2010
- May, 2010
- April, 2010
- March, 2010
- February, 2010
- January, 2010
- December, 2009
- November, 2009
- October, 2009
- September, 2009
- August, 2009
- July, 2009
- June, 2009
- May, 2009
- April, 2009
- March, 2009
- February, 2009
- January, 2009
- December, 2008
- November, 2008
- October, 2008
- September, 2008
- August, 2008
- July, 2008
- June, 2008
- May, 2008
- April, 2008
- March, 2008
- February, 2008
- January, 2008
- December, 2007
- November, 2007
- October, 2007
- September, 2007
- August, 2007
- July, 2007
- June, 2007
- May, 2007
- April, 2007
- March, 2007
- February, 2007
- January, 2007
- December, 2006
- November, 2006
- October, 2006
- September, 2006
- August, 2006
- July, 2006
- June, 2006
Most read articles
|0806 PD: Relocation and expansion planning for dairy producers|
|Archives - Past Articles|
|Wednesday, 23 August 2006 06:31|
Relocating or expanding a dairy facility is a process that requires a tremendous amount of time and planning. Owners or managers of dairies will go through a number of steps including:
•writing a business plan
This article will discuss designing and locating a dairy facility to maximize labor efficiency and cow performance by focusing on milking parlors, cow housing, grouping strategies and site selection.
Options for the milking parlor
Sizing parallel and herringbone milking parlors
Having as many occupied stalls as possible per cycle maximizes parlor efficiency. Typically, it is assumed the milking parlor is turned over 4.5 times per hour during milking. The average number of cows milked per hour can be calculated using the following formulas:
Total number of parlor stalls x 4.5 = cows milked per hour (CPH)
Number of milking cows = CPH x milking shift length (hours)
Sizing rotary parlors
Theoretical throughput assumes the parlor never stops, cows are milked out in one rotation and a new cow occupies every stall at entry. In reality, there are empty stalls, cows not milked out in one rotation and times when the rotary table is stopped. As the number of empty stalls, cows making a second trip around and number of stops increases, the percent of theoretical throughput is decreased.
The number of stalls or size of the rotary parlor affects the available unit on time. A rotary parlor must be large enough to allow approximately 90 percent of the cows to be milked out in one trip around the parlor.
In reviewing data available today, rotary parlors should be sized at an entry time of 11 to 12 seconds per stall rotation and 80 percent of theoretical throughput. The parlor should be large enough to allow nine minutes of available unit on time.
Selecting parlor type
The square footage requirement for parallels range from 1,890 to 5,300 square feet, while the square footage requirement for rotary parlors ranges from 3,025 to 9,216 square feet. Producers need to compare the construction cost of the different parlor types they are considering.
Equipment dealers are estimating basic equipment inside the parlor milk line, wash line, basic detacher and stall at $3,000 per stall for herringbone and parallel parlors and $3,400 for a rotary parlor. In parallel and herringbone parlors, the operator pit can be constructed to allow additional stalls to be added as the dairy expands.
Expanding rotary parlors is difficult. The operator pit can be constructed in parallel and herringbone parlors to allow additional stalls to be added as the dairy expands. In parallel and herringbone parlors, an operator can leave the parlor and the other operators can continue to milk cows at a slower pace. In a rotary parlor, if one operator needs to leave the parlor, he or she will have to be replaced by another operator.
One versus two parlors
Wash pen design
Wash pen use is essential in open-lot dairies. Many new freestall barns are being built without wash pens and depend on proper freestall management to deliver clean cows to the milking parlor.
The necessary area per cow for proper cow cleaning will depend upon several factors:
1. If the wash pen is at a 90-degree angle to the cow traffic lane, additional area is necessary to allow the cows to properly fit into the wash pen.
2. As group size increases, the area per cow increases. With group size up to 200 cows, a wash pen of 15 square feet per cow is adequate. With groups above 200 cows, 16 to 17 square feet per cow will provide adequate space.
Design of the sprinkler system is essential for adequate cow cleaning. With solid (concrete or metal) sidewalls, cows will face toward the parlor. This puts the udder next to the wall. A wash line should be placed 18 to 24 inches from the sidewall and use a pop-up sprinkler design. Such sprinklers are not as efficient as impact sprinklers. However, if all impact sprinklers are used, cows against the wall will not be cleaned well.
After placement of the outside row of sprinklers, the remaining sprinklers should be placed on a 5-foot-by-6-foot grid. For example, a 40-foot wide holding pen with outside rows 2 feet from the sidewalls would have five rows of sprinklers spaced 6 feet apart and 5 feet top to bottom.
Use a three-stage timer to operate the sprinklers. The timings will effect the amount of water used. This wash system is the largest user of water on the farm. Water use will vary from 18 to 30 gallons per cow per wash.
Drip pen design
Provisions should be made to allow for floor mat thickness, if mats are to be used. The curb of the cow platform typically overhangs the operator pit wall 9 to 12 inches, depending on the size of the parlor. Normally, the operator pit and cow platform should have a 1 percent slope to the rear of the milking parlor. Operator pits typically have 2 inches of side slope from the center of the pit to the pit walls.
Constructing the milking parlor shell
When long-term plans include expansion, the shell can be constructed with room to add a second parlor or add stalls to an existing parallel or herringbone parlor. If a second parlor is added, usually the two parlors will share a common equipment and milk storage facility. If additional stalls will be added to a parlor, space should be left in the front of the parlor to reduce cow entry time and allow installation of new stalls without impeding current milking routines. The final size of the holding pen (number of cows per group) should be sized for the total number of cows that will be milked after the expansion.
The milking facility should be properly ventilated to maintain employee and cow comfort. Office, meeting room, break room and restroom facilities should be incorporated to meet the needs of management.
Selecting cow housing
Windbreaks are constructed in areas where winter weather is severe. It is important to realize that drylot housing does not allow managers the luxury of managing the risk Mother Nature can present in the form of rain, snow and severe windchill. The advantage of drylot facilities is the lower capital investment per cow as compared to freestall housing.
Freestall housing usually is selected to minimize the effect of weather changes and to improve cleanliness and cow comfort. Providing a clean, dry bed is essential to minimize the incidence of mastitis in the herd. Comfort refers to providing a comfortable bed and the correct freestall dimensions. This makes it easy for the cow to move in and out of the stall and to lie comfortably in the stall. The disadvantage of freestall housing is the cost of constructing freestall housing and the costs associated with maintaining the beds.
Selecting and locating freestall barns
The advantage of 2-row or 4-row freestall barns is access to feed, more square feet per cow and a lower heat load per stall in the barn. The advantage of 6-row barns is cost; however, producers should be concerned about the level of heat stress and the limited feeding area. Providing supplemental cooling in 6-row barns may be more critical due to the reduction in square feet per stall.
Ventilation and orientation of freestall barns
Curtains on the sides of freestall barns allow greater flexibility in adjusting the environment around the cow. Since warm air rises, steeper-sloped roofs provide upward flow of warm air. Roof slopes for freestall housing with gable roofs should be 4/12. Gable roofs with slopes less than 4/12 may have condensation and higher internal temperatures in the summer.
Providing openings on the end walls in addition to alley doors will improve summer ventilation. Gable buildings should have a continuous ridge opening to allow warm air to escape. The ridge opening should be 2 inches for each 10 feet of building width. Naturally-ventilated buildings should have a minimum of 100 feet between structures and preferably 1.5 to 2 times the building width.
Freestall barns are typically oriented east to west to take advantage of sun angles and provide afternoon shade. Barns constructed north to south will have an overhang on the west side producing desirable shade for stalls on the west side of the barn during the afternoon. Freestall barns should be located within recommended walking distances to the milking center but not restrict natural ventilation.
Field observation in freestall buildings reveal cows begin to bunch up about halfway through the pen. It is not known if this bunching causes additional stress as compared to cows exiting drylot housing. So at this time, we would figure one-half alley length plus the distance from the top of the pen to the holding pen as forced walk distance in freestall barns.
Cow traffic lanes
Group size x .15 x 2 = tank perimeter in feet
The water system must be able to provide 75 to 100 gallons per cow per day. Peak flow rate is determined by number of waterers, assuming 100 percent utilization or milk parlor usage during cleaning. A minimum size well is probably 10 gallons per minute per 100 cows, with 20 to 30 gallons per minute per 100 cows being preferred.
How many crossovers do I need?
Producers often reduce the number of crossovers in freestall barns to reduce construction costs. Reducing the number of crossovers limits the cow’s access to feed and water. It also reduces the total length available to construct the feedline. Very few producers stock freestall barns at one cow per stall. The tendency is to overstock freestall facilities. Therefore, reducing the number of crossovers or the width of crossovers restricts access to feed and water and limits the space for cows at the feedline. The bottom line is that the cows suffer when the number of crossovers is reduced.
Recommended stall dimensions
Stalls that are too long may allow lying too far forward unless brisket boards are used. These conditions increase the possibility of manure being deposited on the stall bed, dirtying bedding. In hot climates, consideration to heat build-up in the freestall area may lead to wider (48 inches) and longer (8 feet) freestalls.
With two rows of freestalls placed head-to-head and designed for space sharing, stall partitions usually are mounted on individual posts to allow for unrestricted open space for the forward lunge into the adjacent stall space. It is important that building support posts are located at multiples equivalent to stall width. This will prevent building support posts from obstructing the lunge space. Freestall width should determine building post spacing, not vice versa.
Group size is determined by the size of the parlor and milking frequency. Observations on commercial dairies indicate a group should be milked in 60 minutes when milking 2X per day, 40 minutes when milking 3X per day and 30 minutes when milking 4X per day. This will constrain the amount of time cows are being kept away from feed and water to no more than two hours per day.
Within the eight groups of healthy lactating cows, individual cows are assigned to pens based on nutritional requirements, reproductive status and social factors. First, heifers respond favorably when grouped separately from older cows. Heifers have lower dry matter intakes (DMI) and greater growth requirements as compared to older cattle. In addition, mixing heifers with older cattle increases social pressure, resulting in less than optimal heifer performance.
Heifers should be kept in separate groups and divided based on reproductive status. Heifers could be grouped as open, not breeding, breeding and pregnant. This increases labor efficiency during breeding by concentrating all breeding activities to one pen. The remaining healthy lactating cows are allotted to groups by reproductive status and nutritional needs. Nutritional requirements for these groups vary and, as above, concentrating breeding activities maximizes labor efficiency.
One disadvantage to the above grouping scheme is the need to move cows from pen to pen. Movement of cattle increases labor requirements and disrupts the social order in a pen. Usually, three to four days are required to reestablish social order when cattle move to a new pen. The result is reduced feed intakes and lost milk production.
As a result, some producers have chosen to freshen cows as a group and maintain the group throughout lactation. Rather than moving the cows to correct diet or management area, this strategy brings the diet and management to the cow. The difficulty in this system is calving enough cows to fill a pen in less than 30 days.
In addition to the healthy lactating cows, some lactating cows will have special requirements. Separating fresh, sick, lame or slow-milking cows increases parlor and treatment labor efficiency, as well as reducing stress on the cattle.
Fresh cows will account for 4 percent of the healthy herd size, assuming the number of calvings annually is 115 percent of lactating cows. The fresh cows should be housed in a loose housing pen for 10 days.
Provisions must be made to segregate nonsalable milk. Careful attention to intake, milk production, health and cow comfort is necessary for cattle in this pen to prosper. The sick pen should handle 2 percent of the healthy lactating cows. Removal of the sick cattle from the healthy pens is necessary for efficient treatment, to prevent antibiotic contamination of milk, and increase cow comfort.
It is recommended the fresh and sick pens be loose housing with sand bedding in order to maximize cow comfort. Lame and slow-milking cows often are housed in the same pen and located close to the milking parlor. Removing slow moving or slow-milking cows from the other pens will increase parlor efficiency 8 to 10 percent. Lame and slow-milking cows will be about 2 percent of the healthy lactating cows and can be housed in freestalls.
On large dairies, nonlactating cattle should be divided into five groups defined as maternity, overconditioned dry cows, underconditioned dry cows, close-up dry cows and close-up heifers. Nutritional needs of these groups vary greatly and grouping of these heifers and cows according to nutritional requirements is critical to minimize metabolic problems associated with calving.
Ideally, cows calve in individual maternity pens. Close attention to close-up pens allows cows that are just beginning the calving process to be moved to the calving pens. Cows normally stay in the maternity pen less than 24 hours. The number of maternity pens needed is approximately equal to .33 percent of the total milking cows.
These plans do not include a quarantine area. True quarantine pens should be located away from this facility. If a true quarantine period were desired, springing heifers would need to be received at another facility at least one month prior to moving to this facility. In general, this is not the typical practice. Thus, the overflow pen will generally be utilized as the receiving pen for replacement heifers.
Site evaluation and selection
Other factors such as waterways, separation distances, neighbors, etc. may limit the area where manure can be applied. The facilities, buildings, feed center and waste management system will require approximately 1 acre per 75 to 100 cows. Initial site evaluation must consider the availability of three-phase electricity, water accessibility and sewer (manure storage and handling). If any one of these four items appears cost-prohibitive or not feasible to obtain, another site should be considered.
Martin notes other factors to consider include:
•Access by milk and feed trucks
The layout of the complete dairy operation will be determined based on plans for:
•Freestall barns (numbers of groups, stall layout, etc.)
Complete plans for waste handling, storage and land application must be developed by a consulting engineering and dairy design team. All regulatory agencies must approve the plans before any construction begins (health department, milk inspector, designated manure regulatory agency, local government, etc.). PD
References omitted due to space but are available upon request.
—From Kansas State University Extension website
J.F. Smith, M.J. Brouk and M.J. Meyer, Department of Animal Sciences and Industry, Kansas State University; J.P. Harner, Department of Biological and Agricultural Engineering, Kansas State University; D.V. Armstrong, Department of Animal Sciences, University of Arizona; M.J. Gamroth, Department of Animal Sciences, Oregon State University; Gene Boomer, Greg Bethard and Dana Putnam, Monsanto Dairy Business