Posilac 1 Step® In Other Countries
Monsanto Dairy Business
Key Points:
POSILAC 1 STEP® and Genetics
Key Points:
The effect of bovine somatotropin is similar to the selection goal of genetic programs and other dairy technologies which is to lower farm fixed costs over units of milk produced. Use of POSILAC bovine somatotropin will not eliminate genetic variation, and selection will continue to be important. There will be challenges in distinguishing between “AI proven bulls” and “BST proven bulls,” which is no different from established practices that have always existed within the industry. Dairy producers who use POSILAC will pay more attention to the contribution genetics can make to increasing productivity.
Genetic progress is likely to increase with POSILAC from the current gain of 125 lbs per year.1 Genetic progress is expected to increase because both the mean and variance are expected to increase in an environment with POSILAC. Genetic progress could be less under an environment with POSILAC compared to current progress if manipulation of records occurs. Manipulated records will decrease the accuracy of cow and sire evaluations. Dairy records rely on the integrity of individual producers. Under current conditions, records can be manipulated by simply offering additional feed, for example. Biases due to POSILAC can be handled if records are properly coded.2
Several computer simulation models1,3,4 indicated that if administration of BST is accurately recorded, then effects on genetic progress will be minimal. The more random the use of BST in the population, the less will be the effect on genetic evaluations, especially for bulls.3 A major problem would arise if individual cows are supplemented with BST and the highest responders are used as bull dams. However, as stated previously, research has not been successful in predicting individual cow responses so manipulation of potential bull dams would be difficult. POSILAC is not recommended for use on any bull dams as we do not have any specific trial data on the effects on male offspring. If the response would be an individual trait, this would lead to a preference for high responders.5 High-yielding cows and daughters of bulls with high PDs will respond to BST equally as well as cows of lower genetic merit.6,7
Dairy farmers with top genetic and production herds will have top genetic and production herds under POSILAC bovine somatotropin.1 The selection goal, increased yield, will remain the same, and will continue to be highly associated with net income within a herd. The top genetic herds will still sell bulls to AI and producers will continue to benefit from sampling young sires.1 The importance of selection will continue to grow with increased emphasis on milk production efficiency. With POSILAC, variation within herds will increase and the top genetic cows will be the best daughters of the best bulls. If all available cows are supplemented, the variance will increase because the mean will increase. If only a part of the herd is supplemented with POSILAC, then there will be a significant increase of within the herd variation because the difference between the highs and the lows will increase.8 This can be handled by adjusting the records for the effect of POSILAC.2
The impact of POSILAC on sire proofs is unknown until widespread adoption within the industry occurs. POSILAC may neutralize the effects of some genes, but is not likely to reverse their actions and cause bulls to rank much differently.1 There might be slight changes in sire rankings and sire proofs, but the net effect is expected to be minimal and the best bulls available today will also rank at the top in a POSILAC environment.
References
1. Everett RW: How will bST affect dairy genetics in the 1990’s? Hoards Dairyman 1987(April 10), p 301.
2. Everett RW, Galton DM, Kachman SD: Dairy genetics in a bST environment. Proc: Advanced Technologies Facing the Dairy Industry: bST. Cornell Cooperative Extension Meeting, Rochester, NY, 1989.
3. Burnside EB, Meyer K: Potential impact of bovine somatotropin on dairy sire evaluations. J Dairy Sci 1988;71:2210.
4. Frangione TA, Cady RA: A simulation study of the effects of somatotropin usage on sire evaluations and milk yield and yield heritabilities. J Dairy Sci 1988;71(Suppl. 1):239.
5. Gravert HO: bST and breeding-overview. Monsanto bST-Symposium, Brussels, May 22-24, 1988.
6. Ferguson JD: Strategies of bST utilization. Proc: Advanced Technologies Facing the Dairy Industry: bST. Cornell Cooperative Extension Meeting, Rochester, NY, 1989.
Source: Monsanto
Economic & Farm Benefits of Using POSILAC 1 STEP®
Key Points:
The benefit of POSILAC is its ability to increase milk production significantly and, in doing so, to lower farm fixed costs over units of milk produced. As with all production-enhancing management practices, the objective of using POSILAC is to provide increased profitability to the dairy producer. Maximum economic response is obtained by following the use instructions described in “POSILAC - Milk Production and Management.” Basically, beginning supplementation of ALL healthy cows beginning in the ninth or tenth week of lactation and providing constant availability of a ration designed to support the increased level of production will result in maximum economic response. The concept is so simple that virtually all producers can use POSILAC to increase the profitability of their herds. POSILAC can help raise the profitability of cows as their lactation progresses. Research has shown that, by following proper use instructions, milk production can increase from 5 to 15 lb/cow/day. The economic benefit of using POSILAC can be calculated by merely subtracting the additional incremental costs associated with using POSILAC from the incremental income. Since use of POSILAC requires no capital investment, all fixed costs of producing milk remain unchanged. Only the variable costs and returns need to be evaluated. To calculate the daily return per cow with POSILAC, multiply the extra pounds of milk produced each day times the mail box price of milk. Subtract the extra costs of producing that amount of milk: the daily cost of POSILAC (price per unit/14) plus the cost of the extra feed required. Refer to Table 1 for some examples.
Table 1 Economic benefit of POSILAC bovine somatotropin
| POSILAC price/14-day supplementation | $5.80 |
| Incremental costs per lb milk response (feed & other costs) | $0.035 |
| Herd size | 100 |
| Percent of herd supplemented | 50% |
Profit/herd/year using POSILAC
| Incremental milk response | 8 lbs | 10 lbs | 12 lbs | |
Incremental cost/profit per cwt for milk produced with POSILAC
| Incremental milk response | 8 lbs | 10 lbs | 12 lbs |
The actual increased profits enjoyed by individual dairy producers will depend on their mail box milk price, the price of POSILAC, feed costs, and the actual response to POSILAC achieved on their farm. Another example of how POSILAC bovine somatotropin provides economic benefit is its use in extending the lactation of cows that would otherwise be culled due to inability to breed or other health or age reasons. The economic benefit in this case depends on factors that are highly variable from farm to farm, and relate to the level of daily production required to break even. Generally speaking, each additional day that a cow is kept in the production string rather than culled can mean an extra $5.00 or more in income. Thus, keeping the cow in production an extra 30 to 100 days provides a significant, positive economic impact. POSILAC can also be used to decrease the number of cows necessary to produce the same amount of milk. This provides additional income from the sale of cull cows, lowers feed costs, and is of particular benefit in areas of the country where per cow facility costs are relatively high. POSILAC may be a particularly valuable management tool for the dairyman who has too high a density of cows for his facility. Since no capital expenditures are required to incorporate POSILAC into a producer’s dairy management regime, the benefits are equally available to producers regardless of size or location. POSILAC can provide economic advantages to virtually all dairy producers.
Focus on the Fundamentals – Financial
Gary Sipiorski, Citizens State Bank of Loyal
Armfelt, Caddy, Weisman
When the milk price drops and stays down as long as it has, emotional decisions are a dairy producer’s first reaction. A better approach may be to Stop, Think, Talk and Calculate the Impact. It is too easy to Fire, Ready, then Aim. Here are a few Dos and Don’ts of which dairy producers should be reminded. Remember, cows are not economists. They react to comfort and care. If you were doing things right with the cows before, you should keep doing those things now.
Do:
1. “Cash Flow” is and always will be King. Think about the impact that each decision will have on the Gross Income. An often asked question: “Why does production go up nation wide when the price of milk drops?” Dairy producers that can, are adding cows or work to achieve higher production to recapture lost Gross Income. The bottom line is to generate cash!
2. Now is the time to really “know your monthly cash expenses”. Sit down with key employees and go through each expense category. In times like these, sit down at the first of the month and write down those anticipated expenses on a pad of paper next to the anticipated income. At the end of the month, review those expected numbers against the real numbers. How did you do? If you missed the acceptable outcome, redo the numbers for next month and discuss what management changes need to be made to make the projected monthly numbers match. It is best to go through this exercise monthly. If you wait for year-end, you may not be there to see the outcome. Computers are fine, but everyone seems to take more responsibility in times like this when you have the pencil in hand.
3. Review key and major expense areas. Feed bills are always at the top of expense categories. Make sure each ingredient is pulling its weight with the cow. Review other major input areas. Resist major changes in those areas that worked before the milk price dropped, like feed protein and POSILAC®. Make sure you are using high quality feed that has the potential to make milk. 4. Talk to your money source people before they want to talk with you. Lenders hate to be surprised. You take the lead to share your balance sheets, cash flows and thought process.5. Talk with time proven advisors that you have come to trust. This list may include your veterinarian, nutritionist, crop specialist, extension personnel and others. They still have good advice to share.
6. Surround yourself with producers that build you up, rather than pull you down! Many of your peers have been through times like these. Talk with those that have positive outlooks and suggestions.
Don’t:
1. Don’t change the things you know are right for the cows. (See “Focus on the Fundamentals - Cow Management”).
2. Don’t buy assets that have a long payback such as land, machinery and pickup trucks.
3. Don’t stop talking to the right people that have been through this before and have been successful.
Source: Monsanto
Authors: Armfelt, Caddy, Weisman
Milking Frequency
By Dennis V. Armstrong
Department of Animal Sciences,
University of Arizona, Tucson
520-621-1923
fax 520-621-9435
Milking Frequency
The majority of present dairy owners and managers probably think that the milking frequency and schedule on the majority of North American dairy farms in the past was twice a day milking at approximately 12-hour intervals. In fact, many variations in milking frequency or different lengths of intermilking intervals have been tried over the last few decades. Usually these have been for social, production management, or economic reasons. As milk production per cow and herd averages have increased, the interest in milking frequency and interval by dairy farm management has also increased. Practices which were considered to be common in the early part of the century, such as once a day milking, twice a day with intervals of 9-14 hours between milking, and even skip-a-milking a day, would not be considered as acceptable in present milking management of high producing cows. A review of past milking practices may help understand what and why about the practices of milking management used today.
Once-A-Day Milking
Milking a cow once a day still is a common practice in some areas of the world where maximum milk production is not always the goal. Once-a-day milking may be more acceptable in some social-labor relationships. It is also common where dairy cattle calve (seasonal) to coincide with the availability of feed. For example, the cows are grazed with the calves for approximately half the day, and then the calves are separated and the cows are milked by hand, usually just before the calf is returned to the cow. The effect of the calves frequent nursing during the day may stimulate milk production was suggested in a trial in 1963 at the University of Minnesota (24).
Even on today’s modern dairy farms, with ice storms, blizzards, and other violent type storms, it is not uncommon to have power outages of over one day. What cows to milk first when the power returns is a management dilemma. The results from a research trial in 1963 (5)which omitted one and two milkings on a weekly basis would indicate that the middle to late lactation will decrease the largest percentage. This could suggest that they should be milked first after a short interruption of the normal milking procedure.
Once-a-day milking has occurred on many dairy farms in the past, although not always a planned event. These unusual happenings, would occur on New Years morning or after a family celebration such as a wedding, were the favorite times of the once-a-day milking. The result of these once-a-day milkings have not been documented as to the loss of milk production.
A trial by Auburn University (5) reported that cows which had one milking a week omitted lost 7% of their milk production, and cows with two milkings a week omitted lost 14%. Similar results were reported by Illinois State University (27), with a loss of 7% for cows with one milking a week omitted.
In New Zealand and Australia, milking cows once-aday in late lactation has been researched. In several trials (9) milk production losses of 18 to 35% have been reported. In a 1953 study at the University of Connecticut (16) cows in late lactation milked once a day produced 10.8 lb per day compared to 17.4 lb per day for twice-a-day cows on a 10-14-hour schedule.
Twice-A-Day Milking (2X)
2x milking is the most common milking schedule of dairy cattle. Only in the last 30 years has the practice of milking on 2x schedule been at twelve-hour intervals. Even today in Midwestern U.S. where the dairyman also is a crop farmer, milking on a 10 to 14-hour schedule is a common practice. In Europe, Australia, and New Zealand 12-hour milking schedule for 2x milking are not common practices. The major reason for the 10 to 14-hour milking interval is usually a social factor.
Research is not conclusive as to the benefits of a 12- hour interval as compared to a 10-14 schedule. In a 1963 Cornell study (34) cows milked at an 8- to 16-hour interval milked only 4.3% less than a 12-hour interval for 2x milking. In the same trial cows milked at a 10- to 14-hour interval produced only 1% less than a 12-hour interval,milk production per cow per year was 15,000 lbs of milk for the Cornell trial. In research trials with cows which had a relatively low daily milk production of 17-28 lb at the University of Minnesota in 1954 (20), New Zealand in 1956 (26) and Australia in 1955 (37), an unequal daily milking interval of 10 to 14 hours for 2x milking did not have a significant decrease in daily milk production when compared to a 12-hour interval. Level of milk production may have contributed to the results of these trials.
A more recent study by the University of Illinois (36) with cows milking over 70 lb of milk daily, a 2=% decrease was observed with cows milked at a 9- to 15-hour interval as compared to cows milked on a 12-hour interval. It is an observation by the author (3) that dairy herds with a daily milk production of more than 60 lb per cow per day on a 10- to 14-hour interval would increase milk production 4 to 6%, when changing to a 12-hour schedule within two weeks of the change.
There is no data available from research trials on intervals between milking to indicate any effect on udder health of different intervals for 2x milking. Therefore, one could hypothesize that the present practice of milking high producing herds on a 12-hour interval for 2x milking will result in higher milk production.
Three-Times-A-Day Milking (3x)
Milking cows 3x has become a common milking frequency in recent years. From 1920 to 1950 milking 3x was usually done only on purebred registered herds to increase milk production on selected cows. The rising cost of facilities per cow, the increase in labor efficiency through parlor mechanization, and higher production per cow have increased the interest in milking 3x to improve the profitability of the dairy enterprise. A response percentage of 3 to 39% for cows changed from 2x to 3x milking intervals has been reported in research literature (6, 11, 14, 15, 25, 30, 31, 39). Management and facilities certainly have an important role in the percentage response to 3x milking. Nutrition requirements for any potential increase in milk production must also be met, with 3x herds being fed three times or more each day. Milking management and milking systems must be of top quality to assure udder health. Walking distance in the lane from the corral or housing area to the milking parlor should not exceed 600 to 700 feet, and group size should not exceed one hour of milking capacity of the parlor. The lack of proper facilities or management can result in a low response to 3x milking frequency.
An additional milking shift will increase labor requirements, although the total time required to milk the same herd size will be approximately 8 to 10% less for 3x than 2x herds (35). For example, a 2x herd which requires 8 hours per milking shift will require 8 to 10% less on 3x or a milking shift of 7 hours. For large dairy herds using hired labor for milking, the organization of the milking shift is less difficult than for smaller farms where family labor is used.
The response to 3x milking also varies by lactation number. In a comparison of seven herds in California in 1986 (1), the increase in milk production for first lactation cows was 19.4%, second lactation 13.5%, third lactation 11.7%, and four or more lactations 13.4%. Another California study in 1986 (13) analyzed monthly herd summaries of 28 herds prior to and for the first 36 months after switching to 3x milking and reported a 12% increase on 3x milking, with first lactation cows increasing 14% in milk yield. In an Arizona study (23) of DHIA records on herds changing from 2x to 3x increased 15% in milk yield within 12 months after changing milk frequency. In a Connecticut study in 1977 (14) of six herds which changed from 2x to 3x, milk yield was increased 7% for second lactation cows and older, and 11% for first lactation cows above their projected 2x yield. British research (32) evaluated 3x milking during the first 20 weeks of lactation and reported an increased milk yield of 19% for multiple lactation cows and 13% for first lactation cows.
The majority of research studies on 3x milking have been to measure milk production. There is less data on the effects of milking on reproduction and udder health, and the data is not conclusive. No effect of 3x milking on reproduction performance was reported in a Georgia research trial in 1985 (2). A California trial in 1986 (1) reported a difference in reproductive performance by lactation number for cows milked 2x vs 3x. Cows during the first lactation milked 3x had more breeding and days open than 2x milked cows, second lactation and more cows showed no difference in days open for 3x vs 2x cows. De Peters et al. in 1985 (10) reported a trend for reproductive performance of 3x milked cows to be poorer than cows milked 2x a day. Gisi et al. in 1986 (13) reported a trend in reduced reproductive efficiency for 3x cows when compared to 2x cows, with days to first breeding less for 3x cows. Cows during the first and second lactation milked 3x had more breeding (0.2) than 2x milked cows; with no difference in third and fourth lactation. Some research reports have suggested that higher milk yields adversely affect reproduction efficiency of cows, even of cows milked 2x (21, 29).
A summary of previous research data would indicate that reproduction efficiency may be lower during the first two lactations for 3x milked cows with no effect on later lactation cows. The decrease in reproductive efficiency if lower is very small and in most of the trials was not statistically significant. Cow longevity was evaluated in the 1986 California trial (1), with fewer cows being culled from the herds milking cow 3x vs. the 2x herds.
Udder health was not affected by 3x milking in a number of research trials. a California trial in 1986 (13) reported no difference in California mastitis test scores. Pearson et al (30 ) reported no difference in udder health for 3x milked cows. When compared to 2x cows in a 1983 trial by Kentucky research workers (39) somatic cell count was lower, and there was no difference in the number of new bacterial infections between 3x and 2x milked cows.
Therefore, if a dairy farm has properly installed and maintained milking equipment and acceptable milking practices, no increase in somatic cell count or clinical mastitis should occur. In conclusion, if herds are well managed 3x milking should increase milk production by 10 to 18%, reproduction efficiency in first and second lactation cows may be slightly lower, and somatic cell count and clinical mastitis may be lower. Conversely, in poorly managed herds or herds with inadequate facilities for 3x milking, this may only aggravate existing problems and would not be advantageous.
Two-And-A-Half-Times-A-Day Milking?
Many dairymen have pushed their facilities past the time necessary to milk all their cows either 3x or 4x. For example, a herd may require 27-28 hours to complete 3x milking. Although there is little research to study the effect of these types of milking intervals, such as 2=x, research in Holland (18, 19) would indicate that a cow does have a biological clock. That is, a cow will have higher milk production if she is milked and fed on the same daily routine. Therefore, if the time of milking is moved 3 to four hours each day, the benefits of the increased frequency in milk production will be reduced. If your milking frequency is 2=x you do not get one-half the benefit of 3x milking. If a dairyman is milking more cows than the milking parlor and labor can milk in a 24- hour period, it probably is preferable to decrease the milking frequency so that milking and feeding are done on the same routine each day.
Source: University of Arizona
The Impact of Dairy Herd Management on Nutrient Losses to Water Resources By Richard Kohn, Ph.D., University of Maryland
Introduction Current programs to reduce nutrient losses from farms have focused on soil and manure management. These practices by themselves are not adequate to reduce nutrient losses by 40% as needed to restore the Chesapeake Bay ecosystem.
The feeding and management of dairy cattle have a profound impact on reducing nutrient losses to water resources. With improved herd management, less manure is produced so fewer manure nutrients are left to runoff or be leached. In addition, productivity can be maintained with less feed, which means there is a lower requirement for crop production and fertilizer use.
The objectives of the current research are 1) to evaluate new technologies in herd management and feeding for their potential to reduce nitrogen and phosphorus excretion in manure, and their potential to reduce nutrient losses from the farm, 2) to estimate the cost-effectiveness of these technologies, and 3) to make recommendations for technology transfer, cost-share, tax credit, or other incentive programs to encourage implementation of desired programs.
Several new technologies were evaluated for their impact on changes in nutrient excretion to manure by summarizing data in the literature and developing mathematical models. Most animal research is conducted on individual animals and so the impact on the herd was calculated from the results of animal trials by aggregating according to expected herd distributions. The predicted change in nutrient losses from the farm that results from application of new technologies was calculated using a model adapted from previous efforts.
This research was supported by the US EPA Chesapeake Bay Program.
Results
Conclusions
Using multiple strategies to improve nutrient utilization in dairy cattle could reduce N and P feeding by more than 50%. About half the manure N will be lost from the farm before becoming available to crops in soils, and about half of the soil available N will be lost from the soil before being taken up and harvested in crops. With these assumptions, reducing feed N requirements by 50% without harming production could reduce the need for feed N by 50%, and reduce manure N output by 59%. In a typical dairy production system (including the production of imported feeds), improving N utilization in the animal by 50% would decrease total farm N losses by 55%.
Source: University of Maryland
Author: Richard Kohn, PhD
Environmental Benefits of rbST Supplements
PRODUCING MILK USING FEWER RESOURCES & GENERATING LESS WASTE
The net benefits of producing 10% more milk than the 1996 annual supply (19 billion gallons) using the same number of dairy cows and 100% adoption of rbST would include:
Gases – methane (greenhouse) gases from cows. 100% adoption of supplemental rbST would reduce 4.9 million tons/yr gas emissions.
Manure – 100% adoption of supplemental rbST would reduce 0.9 million metric tons/yr of manure.
Soil loss — erosion from grain farming. 100% adoption of supplemental rbST would reduce 5.3 million tons/yr soil loss, or 1% of the U.S. total soil.
Source: Kansas State University
Author: Brouck, Smith
(TTV) FLUSH SYSTEM FOR DAIRY FACILITIES
J.P. Harner, J.P. Murphy and J.F. Smith
summary
Flushing characteristics of a tower tank valve flushing system with 12 in diameter manual valve were determined. Data were obtained using the outside cow alleys in a four row freestall barn. The alleys were 12 ft wide and 420 ft long with a 2 percent slope. The average flow rate exceeded 8,000 gpm when the average head was above 30 ft and the manual valve opened 80 degrees. Opening the valve to 90 degrees increased the flow rate to over 9,700 gpm. The velocity of the flushing wave was 8.5 fpm with a flow depth of 3.5 in. The estimated wave duration or alley contact time was 14.6 sec with a 25-40 sec release time from the flush tank. The flow rate ranged from 5,300 gpm to 7,200 gpm when the average head was between 16 and 28 ft.
(Key Words: Flushing, Manure, Water, Freestall.)
Introduction
Flushing systems which collect and transport manure are utilized in dairy operations.
It offers the advantage of labor reduction with automated systems, limited scraping requirements, lower operating cost, drier floors, potential reduction in odor and cleaner facilities. An optional method of handling the manure may be necessary during colder weather which is a disadvantage. Other disadvantages include the water requirements per cow and the initial fixed cost.
Designed flush systems utilize a flush device to release the correct volume of water at the appropriate discharge rate and length of time. This achieves the designed flow velocity, contact time, and depth of water in the gutter to obtain adequate cleaning.
Daily water requirements for flushing vary depending on the width, length and slope of the flushed area. Buildings with alleys sloping 2 to 4 percent will use less water for flushing when compared to alleys with a 1 percent slope. At an optimal slope of 3 percent, a minimum flush volume is 100 gal per ft of gutter width for flushing lengths of less than 150 ft. Longer lengths require more water with a suggested maximum release of 175 gal per ft. One study found 40 to 50 gal per cow per flush were required for effective flushing. A study of six dairies found flush water requirements ranging from 240 to 620 gal per cow per day. Another design procedure suggests selecting the larger of two volumes - either 52 gal per cow per flush or 1.35 gal per sq ft of alley per flush.
Most flushing systems utilize purchased components which include pipe line systems using pop-up valves or plates and underground piping. The objective of this study was to develop a tower tank valve (TTV) flushing system which could be incorporated into an existing or new dairy using sand bedded freestalls. Desired flushing characteristics included a release rate of 9,000 to 10,000 gpm, water usage of 4,200 gal per flush, 30 sec flushing interval and the ability to move sand laden manure. Procedures A TTV system was installed at a dairy in North Central Kansas. The freestall building was 420 ft long with a 2 % slope. The alleys had a one in slope towards the freestall curb from the outside wall. The four row barn had 84 freestalls per row. The feed alley was 14 ft wide and the cow alley was 12 ft wide.
The TTV flush system consisted of open-top flush tanks which are 10.4 ft. in diameter and 38.5 ft. tall. The flushing system uses a 6 to 7 ft section of 16 in pipe exiting the tank at a right angle. The 16 in pipe has a 45 degree slope inside the tank. Another 6 to 7 ft section of 12 in pipe, which includes a 12 in manual gate value, is then used to carry the water to the flush alleys. The pipe outlet directs the water along the freestall curb.
Data and measurements were taken using the upper 200 ft of the 12 ft alleys while the cows were milking. Except for the first flush, the alleys were free of manure and sand. During the study, the gate value was opened 80 degrees for the first study and then 90 degrees during the sec.
Tests were conducted at the site on two separate days. Measurements taken during the study used the 12 ft outside alleys and the data averaged together based on initial head. The flush water velocity was measured at a distance of 50 ft and 100 ft from a reference point. The reference point was located 90 ft from the outlet of the flush tank. The water front reached uniform flow prior to the reference point. Stop watches were started as the wave front passed the reference point and then stopped as it traveled past the known distance. The flush velocity was determined by averaging the velocities of the wave traveling 50 and 100 ft.
The flush tanks were equipped with pressure gages to measure the water pressure before and after each flush. The difference in pressure was used to determine the drop in water elevation and the water volume released. The average discharge rate was determined by the water volume release during a given time. The time interval was based on the time the valve was opened. The actual flush was normally 2 to 3 sec longer which was the time interval required to fully open the valve. The flush value was closed after the front had traveled 200 ft. or approximately 30 sec. The steady state release volume was not measured. However, based on Bernoulli equation and using the friction losses of the different components, the estimate steady state rate was 10,500 gpm.
The flow depth was determined at the reference point and the 50 and 100 ft intervals. The depth was determined by measuring the distance from the top of the curb to the top of the flush water and then subtracting this value from the total curb height. After the flush tanks were filled, the fill value was closed. Multiple tests were conducted until the tank depth was below 10 ft.
Results and Discussions
Table 1 present the results of the data collected when the valve was 80 degrees open. The discharge rate was a function of initial head and varied from 8,700 gpm to 5,000 gpm. The initial head varied from 34 ft to 16 ft. The wave velocity ranged from 7 to 10 fpm with an overall average of 8.5 fpm. The average water depth was 4 in.
Table 2 presents the results of the sec. study with the valve opened 90 degrees. Discharge rates increased a minimum of 500 gpm as compared to opening the valve only 80 degrees with a similar initial head. There was a reduction in velocity from 11.5 fps to 6.7 fps as the head reduced from over 30 ft to less than 10 ft. The depth of wave also reduced about 50 percent as the initial head reduced.
The water usage based on a 8,500 gpm discharge rate and a 30 sec flush is equal to 0.84 gal per square ft, a flow rate of 700 gpm per ft width of gutter and a water usage of 350 gal per ft of gutter. Based on number of freestalls and flushing three times per day, the water usage was 48 gal per stall per flush or 140 gal per day per stall. Based on a 30 sec flush three times per day in the milk parlor, the water usage in the milk parlor was 39 gal per stall per day. The flush system removed the sand and manure from the alleys based on visual inspections.
Summary
Procedures were developed for determining on-site the performance flushing systems. The flushing parameters of tower tank valve flush system exceeded current design recommendations. The modifications simplified the construction process and ease of maintenance. If repairs are necessary, the whole system does not have to be drained unless the pump has to be replaced. The manual values can be replaced by electric driven actuators with flush intervals based on time. The TTV flush system is also able to adapt to existing dairies providing there is room to handle the flush water at the lower end. One disadvantage to a TTV flush systems is more tanks are required. The initial cost appears to be similar to pipe line systems which use underground piping to equalize the pressure between two tanks.
It is important that the flush tank release rate be considered at the upper and lower end of the alleys. Sand traps and gravity solid settling basins need to be designed to handle higher velocities of flush water. Based on visual inspection of the alleys, it is suggested with sand bedded freestalls the minimum flush velocity be 7.5 fps with 10 fps being preferred. Current recommendations on release rates appear to be adequate based on this study and with 400 ft alleys. The water depth at the freestall curb should be a minimum of 3 in with 4 in preferred. The energy of the flush water needs to be directed along the freestall curb rather than in the center of the alley with sand bedded freestalls. This enables the flushing system to remove sand away from the curbs and avoids having to occasionally scrape the sand away from the curbs. Properly designed flush systems can be utilized for effective removal of sand laden manure in new or existing dairy facilities.
Table: 1 Characteristics of flushing system with valve 80 degrees open
| Initial Head (ft) | No. of Rep | Velocity (fps) | Flow Rate1 (gpm) | Flow Depth(in) | Contact Time2 (sec) |
| ? 30 | 2 | 10.6 | 8,420 | 4.9 | 11.5 |
| 26 - 30 | 2 | 9.8 | 8,150 | 3.9 | 13.9 |
| 21-25 | 3 | 8.5 | 6,360 | 4.2 | 12.2 |
| 16-20 | 3 | 7.8 | 5,670 | 3.7 | 13.0 |
| 11-15 | No measurements taken | ||||
| 6-10 | No measurements taken | ||||
1 Average flow rate based on from opening to closing of valve.
2 Estimated based on released rate, flow depth, velocity.
Table: 2 Characteristics of flushing system with valve 90 degrees open
| Initial Head (ft) | No. of Rep | Velocity (fps) | Flow Rate 1 (gpm) | Flow Depth(in) | Contact Time 2 (sec) |
| ? 30 | 3 | 11.5 | 9,740 | 3.6 | 11.2 |
| 26 - 30 | 3 | 10.8 | 8,630 | 3.6 | 11.9 |
| 21-25 | 2 | 9.4 | 7,760 | 3.0 | 13.4 |
| 16-20 | 3 | 8.3 | 7,390 | 3.3 | 15.4 |
| 11-15 | 3 | 7.6 | 5,940 | 3.0 | 16.3 |
| 6-10 | 3 | 6.7 | 5,010 | 2.5 | 20.0 |
1 Average flow rate based on from opening to closing of valve.
2 Estimated based on released rate, flow depth, velocity.
Source: Kansas State University
Author: Murphy Smith
| Title: | Principles of Cooling Cows… | |
| Source: | Kansas State University | |
| Author: | Brouck, Smith | |
| Date: | ||
| Content : |
Cooling Cows:
How Does Sprinkling Frequency and Airflow Impact Animal Response?
M.J. Brouk, J.F. Smith, and J.P. Harner
Kansas State University
Summer heat stress is just around the corner and the results of a study conducted by the dairy team from Kansas State University will help you keep your cows cooler this summer. Have you ever wondered if you should soak cows, increase airflow or both? Many producers have questioned which is most important. Last summer the team conducted a study to determine the effect of soaking frequency and airflow on respiration rates and skin temperature of heat stressed dairy cattle. Sixteen heat stressed lactating cows (8 primiparous and 8 multiparous) were arranged in a replicated 8×8 Latin Square design. Cattle were housed in freestall dairy barns and milked 2x. During testing, cattle were moved to a tie-stall barn for a 2-hour period from either 1- 3 pm or 3-5 pm on 8 different days in late August and early September. Afternoon temperatures ranged between 88 and 96 °F. During the testing period, respiration rates were determined every five minutes by visual evaluation. Skin temperature of three sites was measured with an infrared thermometer and recorded every 5 minutes. Treatments (Table 1) were 4 different soaking frequencies with and without supplemental airflow. Soaking frequencies were control (no soaking), every 5, every 10 or every 15 minutes. Supplemental airflow was either none or 700 cfm. Each soaking cycle provided similar amounts of water for all treatments. Initial data were collected for three 5-minute periods prior to the start of the treatments.
Cows soaked every 5 minutes with supplemental airflow (5+F) responded with the fastest and largest drop in respiration rate reducing the initial respiration rate by 47% at the end of 90 minutes of treatment (Figures 1 and 2). Soaking cows every 5 minutes without airflow (5) resulted in a similar response as soaking cows every 10 minutes with airflow (10+F). Soaking cows every 15 minutes with airflow (15+F) and soaking cows every 10 minutes without airflow (10) resulted in similar responses until the last 30 minutes of the study. Supplemental airflow without soaking (0+F) resulted in little improvement over no soaking or airflow (0). Soaking had a greater effect on respiration rate than airflow. However, the combination of wetting and airflow had the greatest effect on the respiration rate. When cooling heat stressed dairy cattle, the most effective treatment included continuous supplemental airflow and wetting every 5 minutes.
Skin temperatures are shown in figures 3, 4 and 5. Temperature of the thurl and ear were likely directly affected by the presence of water from the soaking procedure. However, the skin temperature of the rear udder was not directly affected by water from soaking. The rear udder skin remained dry throughout treatment. The reduction in rear udder skin temperature is the result of cattle directing less blood flow to the skin surface. This indicates that the cooling 2 systems were reducing heat stress as indicated by a reduction in respiration rates. The most effective treatment was the 5 minute soaking with supplemental air flow.
This data suggests that different cooling strategies could be developed for different levels of heat stress. Under severe heat stress soaking every 5 minutes with fan cooling will be the most effective. Under periods of moderate stress soaking every 10 minutes with fan cooling may be adequate. Reducing soaking frequency when temperatures are lower could significantly reduce water usage. Data clearly indicate that the combination of soaking and supplemental fan cooling are superior to either single treatment. If used singularly, soaking cows would have more impact than the use of fans only for cow cooling. These data indicate that about 1/3 of the total reduction in cow respiration rates was due to airflow and the remainder due to soaking. Under periods of severe heat stress, soaking every 15 minutes with airflow is not adequate and soaking frequency must be increased.
These data also suggest that different cooling strategies might be nearly as effective. For example, the effects of the 10 + F treatment were similar to those of the 5 minute soaking interval without supplemental airflow. This was also true of the 15 + F and 10 minute soaking interval without supplemental airflow. In situations where supplemental airflow is not provided, increasing soaking frequency may provide similar heat abatement as less frequent soaking with supplemental airflow. However, the data does clearly show that maximum cooling is achieved with frequent soaking with supplemental airflow.
Cow cooling with soaking and supplemental airflow is very effective in reducing respiration rate. Many systems may be ineffective because they do not deliver adequate water to soak the cow and/or have an inadequate soaking frequency.
Table 1. Experimental Treatments
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| Treatment | Soaking frequency* | Supplemental Airflow |
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| 0 | None | None |
| 0 + F | None | 700 cfm |
| 5 | Every 5 minutes | None |
| 5 + F | Every 5 minutes | 700 cfm |
| 10 | Every 10 minutes | None |
| 10+ F | Every 10 minutes | 700 cfm |
| 15 | Every 15 minutes | None |
| 15+ F | Every 15 minutes | 700 cfm |
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*.35 gallon/headlock applied in 1 minute
Figure 1. Effect of Sprinkling Frequency and Airflow on Respiration Rate of Heat Stressed Dairy Cattle
Figure 2. Initial, Final and Percentage of Initial Respiration Rate of Heat Stressed Dairy Cattle Treated with Different Cooling Strategies
Figure 3. Cooling strategy effect on thurl skin temperature over 1.5 hours of cooling.
Figure 4. Cooling strategy effect on shoulder skin temperature over 1.5 hours of cooling.
Figure 5. Cooling strategy effect on rear udder skin temperature over 1.5 hour of cooling.
Herd Management Opportunities for Decreasing the Nitrogen Load on the Dairy Farm
Charles G. Schwab, University of New Hampshire, Durham, and Rick A. Kohn,University of Maryland, College Park
INTRODUCTION
Dairy farming in the United States faces two major challenges, an economic challenge and an environmental challenge. The solution to the economic challenge continues to be one of becoming more efficient. Two ways of becoming more efficient has been to increase milk production per cow (i.e., rolling herd average) and to increase cow numbers.
Unfortunately, increasing cow numbers on the farm has contributed to the environmental challenge. From an environmental point of view, in regard to nitrogen, there are two major areas of increasing concern. The first is the pollution of surface water (e.g., streams, lakes, wetlands and estuaries) and ground water from excessive land application of nitrogen. Some nitrogen may be lost with runoff water after a rainfall (Baker and Senft, 1993). Nitrogen incorporated into the soil in excess of crop needs is eventually lost to ground water (Joshi et al., 1994).
The second environmental concern is the volatilization of manure nitrogen into ammonia and its emission into the air. Ammonia contributes to acid rain that endangers forests and lakes (Luebs et al., 1973). Also, some nitrogen may be lost from the farm by conversion to atmospheric N2 in a process known as denitrification (Thompson et al., 1987). Studies indicate that up to 50% of manure nitrogen can be lost to the atmosphere during handling, storage, and land application (Borton et al., 1995; Hutson et al., 1998). The problem is that 60 to 80% of the nitrogen imported onto most dairy farms in the form of feed and commercial fertilizers stays on the farm. The reason for this is that only about 30% of the nitrogen consumed by lactating cows in high producing herds is transferred to the milk, the remainder is excreted in feces and urine (Wilkerson et al., 1997).
It is becoming increasingly clear that how we handle nitrogen and other nutrients (particularly phosphorus) on the dairy farm will affect both farm profitability and the number of animals per unit of cropland that will be allowed. The challenge is to find the appropriate balance between environmental stewardship and an efficient,economically viable dairy production system.Thus, the goal is to increase dairy farm efficiency and profitability while maintaining or reducing nutrient losses to the environment.
The purpose of this presentation is to compare the potential impact of some of the newer technologies in dairy cattle feeding and management on reducing nitrogen losses per unit of milk produced from typical dairy farms.
These technologies are grouped into those aimed at improving biological efficiency through increased production and those aimed at providing a better match of protein sources with the animal’s needs. The reader is referred to other publications that focus on manure, soil, and crop management practices as strategies for reducing nitrogen losses to the environment (e.g., Borton et al., 1997; Joshi et al., 1994; Van Horn et al., 1994).
Source: Monsanto Dairy Group
Author: Schwab, Durham, Cohn
