Dairy farming, milk

 

Dairy farming is a class of agriculture for long-term production of milk, which is processed (either on the farm or at a dairy plant, either of which may be called a dairy) for eventual sale of a dairy product.

A rotary milking parlor at a modern dairy facility, located in Germany

Common types 

Although any mammal can produce milk, commercial dairy farms are typically one-species enterprises. In developed countries, dairy farms typically consist of high producing dairy cows. Other species used in commercial dairy farming include goats, sheep, water buffaloes, and camels. In Italy, donkey dairies are growing in popularity to produce an alternative milk source for human infants.[1]

History 

lking cattle in ancient Egypt

While cattle were domesticated as early as 12,000 years ago as a food source and as beasts of burden, the earliest evidence of using domesticated cows for dairy production is the seventh millennium BC – the early Neolithic era – in northwestern Anatolia.[2] Dairy farming developed elsewhere in the world in subsequent centuries: the sixth millennium BC in eastern Europe, the fifth millennium BC in Africa, and the fourth millennium BC in Britain and Northern Europe.[2]

In the last century or so larger farms specialising in dairy alone have emerged. Large scale dairy farming is only viable where either a large amount of milk is required for production of more durable dairy products such as cheese, butter, etc. or there is a substantial market of people with money to buy milk, but no cows of their own. In the 1800s von Thünen argued that there was about a 100-mile radius surrounding a city where such fresh milk supply was economically viable.

Hand milking cows morden

Woman hand milking a cow.

Hand milking on a farm in Namibia

Centralized dairy farming as we understand it primarily developed around villages and cities, where residents were unable to have cows of their own due to a lack of grazing land. Near the town, farmers could make some extra money on the side by having additional animals and selling the milk in town. The dairy farmers would fill barrels with milk in the morning and bring it to market on a wagon. Until the late 19th century, the milking of the cow was done by hand. In the United States, several large dairy operations existed in some northeastern states and in the west, that involved as many as several hundred cows, but an individual milker could not be expected to milk more than a dozen cows a day. Smaller operations predominated.

For most herds, milking took place indoors twice a day,[3] in a barn with the cattle tied by the neck with ropes or held in place by stanchions. Feeding could occur simultaneously with milking in the barn, although most dairy cattle were pastured during the day between milkings. Such examples of this method of dairy farming are difficult to locate, but some are preserved as a historic site for a glimpse into the days gone by. One such instance that is open for this is at Point Reyes National Seashore.[4]

Dairy farming has been part of agriculture for thousands of years. Historically it has been one part of small, diverse farms. In the last century or so larger farms concentrating on dairy production emerged. Large scale dairy farming is only viable where either a large amount of milk is required for production of more durable dairy products such as cheese, butter, etc. or there is a substantial market of people with cash to buy milk, but no cows of their own. Dairy farms were the best way to meet demand.

Hand milking

Demonstration of a new Soviet milker device. East Germany, 1952

The first milking machines were an extension of the traditional milking pail. The early milker device fit on top of a regular milk pail and sat on the floor under the cow. Following each cow being milked, the bucket would be dumped into a holding tank. These were introduced in the early 20th century.

This developed into the Surge hanging milker. Prior to milking a cow, a large wide leather strap called a surcingle was put around the cow, across the cow's lower back. The milker device and collection tank hung underneath the cow from the strap. This innovation allowed the cow to move around naturally during the milking process rather than having to stand perfectly still over a bucket on the floor.

Milking pipeline 

Main article: milking pipeline

The next innovation in automatic milking was the milk pipeline, introduced in the late 20th century. This uses a permanent milk-return pipe and a second vacuum pipe that encircles the barn or milking parlor above the rows of cows, with quick-seal entry ports above each cow. By eliminating the need for the milk container, the milking device shrank in size and weight to the point where it could hang under the cow, held up only by the sucking force of the milker nipples on the cow's udder. The milk is pulled up into the milk-return pipe by the vacuum system, and then flows by gravity to the milkhouse vacuum-breaker that puts the milk in the storage tank. The pipeline system greatly reduced the physical labor of milking since the farmer no longer needed to carry around huge heavy buckets of milk from each cow.

The pipeline allowed barn length to keep increasing and expanding, but after a point farmers started to milk the cows in large groups, filling the barn with one-half to one-third of the herd, milking the animals, and then emptying and refilling the barn. As herd sizes continued to increase, this evolved into the more efficient milking parlor.

Milking parlors 

Efficiency of four different milking parlors.

Bali-Style 50 cows/h

Swingover 60 cows/h

Herringbone 75 cows/h

Rotary 250 cows/h

Innovation in milking focused on mechanizing the milking parlor (known in Australia and New Zealand as a milking shed) to maximize the number of cows per operator which streamlined the milking process to permit cows to be milked as if on an assembly line, and to reduce physical stresses on the farmer by putting the cows on a platform slightly above the person milking the cows to eliminate having to constantly bend over. Many older and smaller farms still have tie-stall or stanchion barns, but worldwide a majority of commercial farms have parlors.

Herringbone and parallel parlors 

In herringbone and parallel parlors, the milker generally milks one row at a time. The milker will move a row of cows from the holding yard into the milking parlor, and milk each cow in that row. Once all of the milking machines have been removed from the milked row, the milker releases the cows to their feed. A new group of cows is then loaded into the now vacant side and the process repeats until all cows are milked. Depending on the size of the milking parlor, which normally is the bottleneck, these rows of cows can range from four to sixty at a time. The benefits of a herringbone parlour are easy maintenance, the durability, stability, and improved safety for animals and humans when compared to tie stall [5] The first herringbone shed is thought to have been built in 1952 by a Gordonton farmer.[6]

Rotary parlors 

Rotary milking parlor

In rotary parlors, the cows are loaded one at a time onto the parlor as the whole thing rotates in a circle. One milker stands near the entry to the parlor and pre-dips the teats on the udder to help prevent bacteria from entering. The next milker puts the machine on the cow to begin milking. By the time the platform has completed almost a full rotation, the cow is done milking and the unit will come off automatically. The last milker will post-dip her teats to protect them before entering back into the pen. Once this process is done, the cow will back out of the parlor and return to the barn. Rotary cowsheds, as they are called in New Zealand, started in the 1980s[7][8] but are expensive compared to Herringbone cowshed – the older New Zealand norm.[9]

Automatic milker take-off

It can be harmful to an animal for it to be over-milked past the point where the udder has stopped releasing milk Consequently, the milking process involves not just applying the milker, but also monitoring the process to determine when the animal has been milked out and the milker should be removed. While parlor operations allowed a farmer to milk many more animals much more quickly, it also increased the number of animals to be monitored simultaneously by the farmer. The automatic take-off system was developed to remove the milker from the cow when the milk flow reaches a preset level, relieving the farmer of the duties of carefully watching over 20 or more animals being milked at the same time.[citation needed]

Fully automated robotic milking

An automatic milking system unit as an exhibit at a museum

Further information: Automatic milking

In the 1980s and 1990s, robotic milking systems were developed and introduced (principally in the EU). Thousands of these systems are now in routine operation. In these systems the cow has a high degree of autonomy to choose her time of milking freely during the day (some alternatives may apply, depending on cow-traffic solution used at a farm level). These systems are generally limited to intensively managed systems although research continues to match them to the requirements of grazing cattle and to develop sensors to detect animal health and fertility automatically. Every time the cow enters the milking unit she is fed concentrates and her collar is scanned to record production data.

History of milk preservation methods 

Cool temperature has been the main method by which milk freshness has been extended. When windmills and well pumps were invented, one of their first uses on the farm, besides providing water for animals themselves, was for cooling milk, to extend its storage life, until it would be transported to the town market.

The naturally cold underground water would be continuously pumped into a cooling tub or vat. Tall, ten-gallon metal containers filled with freshly obtained milk, which is naturally warm, were placed in this cooling bath. This method of milk cooling was popular before the arrival of electricity and refrigeration.

Refrigeration 

When refrigeration first the equipment was initially used to cool cans of milk, which were filled by hand milking. These cans were placed into a cooled water bath to remove heat and keep them cool until they were able to be transported to collect facilities. As more automated methods were developed for eating milk, hand milking was replaced and, as a result, the milk can was replaced by a bulk milk cooler. 'Ice banks' were the first type of bulk milk cooler. This was a double wall vessel with evaporator coils and water located between the walls at the bottom and sides of the tank. A small refrigeration compressor was used to remove heat from the evaporator coils. Ice eventually builds up around the coils, until it reaches a thickness of about three inches surrounding each pipe, and the cooling system shuts off. When the milking operation starts, only the milk agitator and the water circulation pump, which flows water across the ice and the steel walls of the tank, are needed to reduce the incoming milk to a temperature below 5 degrees.

This cooling method worked well for smaller dairies, however was fairly inefficient and was unable to meet the increasingly higher cooling demand of larger milking parlors. In the mid-1950s direct expansion refrigeration was first applied directly to the bulk milk cooler. This type of cooling utilizes an evaporator built directly into the inner wall of the storage tank to remove heat from the milk. Direct expansion is able to cool milk at a much faster rate than early ice bank type coolers and is still the primary method for bulk tank cooling today on small to medium-sized operations.

Another device which has contributed significantly to milk quality is the plate heat exchanger (PHE). This device utilizes a number of specially designed stainless steel plates with small spaces between them. Milk is passed between every other set of plates with water being passed between the balance of the plates to remove heat from the milk. This method of cooling can remove large amounts of heat from the milk in a very short time, thus drastically slowing bacteria growth and thereby improving milk quality. Ground water is the most common source of cooling medium for this device. Dairy cows consume approximately 3 gallons of water for every gallon of milk production and prefer to drink slightly warm water as opposed to cold ground water. For this reason, PHE's can result in drastically improved milk quality, reduced operating costs for the dairymen by reducing the refrigeration load on his bulk milk cooler, and increased milk production by supplying the cows with a source of fresh warm water.

Plate heat exchangers have also evolved as a result of the increase of dairy farm herd sizes in the United States. As a dairyman increases the size of his herd, he must also increase the capacity of his milking parlor in order to harvest the additional milk. This increase in parlor sizes has resulted in tremendous increases in milk throughput and cooling demand. Today's larger farms produce milk at a rate which direct expansion refrigeration systems on bulk milk coolers cannot cool in a timely manner. PHE's are typically utilized in this instance to rapidly cool the milk to the desired temperature (or close to it) before it reaches the bulk milk tank. Typically, ground water is still utilized to provide some initial cooling to bring the milk to between 55 and 70 °F (13 and 21 °C). A second (and sometimes third) section of the PHE is added to remove the remaining heat with a mixture of chilled pure water and propylene glycol. These chiller systems can be made to incorporate large evaporator surface areas and high chilled water flow rates to cool high flow rates of milk.

Milking operation 

Management of the herd 

Concerns 

Market Edit

Worldwide Edit

Holstein cows on a dairy farm, Comboyne, New South Wales

Dairy farm in Võru Parish, Estonia

There is a great deal of variation in the pattern of dairy production worldwide. Many countries which are large producers consume most of this internally, while others (in particular New Zealand), export a large percentage of their production. Internal consumption is often in the form of liquid milk, while the bulk of international trade is in processed dairy products such as milk powder.[citation needed]

The milking of cows was traditionally a labor-intensive operation and still is in less developed countries. Small farms need several people to milk and care for only a few dozen cows, though for many farms these employees have traditionally been the children of the farm family, giving rise to the term "family farm".[citation needed]

Advances in technology have mostly led to the radical redefinition of "family farms" in industrialized countries such as Australia, New Zealand, and the United States. With farms of hundreds of cows producing large volumes of milk, the larger and more efficient dairy farms are more able to weather severe changes in milk price and operate profitably, while "traditional" family farms generally do not have the equity or income other larger scale farms do. The common public perception of large corporate farms supplanting smaller ones is generally a misconception, as many small family farms expand to take advantage of economies of scale, and incorporate the business to limit the legal liabilities of the owners and simplify such things as tax management.[citation needed]

Before large scale mechanization arrived in the 1950s, keeping a dozen milk cows for the sale of milk was profitable. Now most dairies must have more than one hundred cows being milked at a time in order to be profitable, with other cows and heifers waiting to be "freshened" to join the milking herd. In New Zealand, the average herd size increased from 113 cows in the 1975–76 season to 435 cows in 2018–19 season.[47]

Worldwide, the largest cow milk producer is the United States,[48] the largest cow milk exporter is New Zealand,[49][50] and the largest importer is China.[51] The European Union with its present 27 member countries produced 158,800,000 metric tons (156,300,000 long tons; 175,000,000 short tons) in 2013[52](96.8% cow milk), the most by any politico-economic union.

Supply management 

The Canadian dairy industry is one of four sectors that is under the supply management system, a national agricultural policy framework that coordinates supply and demand through production and import control and pricing mechanisms designed to prevent shortages and surpluses, to ensure farmers a fair rate of return and Canadian consumer access to a high-quality, stable, and secure supply of these sensitive products.[53] The milk supply management system is a "federated provincial policy" with four governing agencies, organizations and committees—Canadian Dairy Commission, Canadian Milk Supply Management Committee (CMSMC), regional milk pools, and provincial milk marketing boards.[54]:8 The dairy supply management system is administered by the federal government through the Canadian Dairy Commission (CDC), which was established in 1966 and is composed mostly of dairy farmers, administers the dairy supply management system for Canada's 12,000 dairy farms.[55] The federal government is involved in supply management through the CDC in the administration of imports and exports.[56] The Canadian Milk Supply Management Committee (CMSMC) was introduced in 1970 as the body responsible for monitoring the production rates of milk and setting the national Market Sharing Quota (MSQ) for industrial raw milk.[57]:31[58] The supply management system was authorized in 1972 through the Farm Products Agencies Act.[53] Supply management ensures consistent pricing of milk for farmers with no fluctuation in the market.[59] The prices are based on the demand for milk throughout the country and how much is being produced. In order to start a new farm or increase production more share into the SMS needs to be bought into known as “Quota”. in this case farmers must remain up to or below the amount of “quota” they have bought share of. Each province in Canada has their own cap on quota based on the demand in the market.[58][60] There is a cap on the countries quota known as total quota per month. In 2016 the total butter fat produced per month was 28,395,848 kg.[61]

World Milk Production 

Total milk production, measured in tonnes per year, per continent.

World total milk production in 2017

FAO statistics [62]

(including cow/buffalo/goat/sheep/camel milk)

Rank Country Production (1000 tonnes/year) Share in Global Production

  World 827,884 100%

1 India 176,272 21.29%

2 United States 97,760 11.81%

3 Pakistan 44,293 5.35%

4 China 34,869 4.21%

5 Brazil 33,742 4.08%

6 Germany 32,695 3.95%

7 Russia 31,177 3.77%

8 France 25,260 3.05%

9 New Zealand 21,372 2.58%

10 Turkey 20,700 2.50%

11 United Kingdom 15,256 1.84%

12 Netherlands 14,544 1.76%

13 Poland 13,702 1.66%

14 Italy 12,027 1.45%

15 Mexico 11,988 1.45%

16 Ukraine 10,520 1.27%

17 Uzbekistan 10,167 1.23%

18 Argentina 10,097 1.22%

19 Australia 8,800 1.06%

20 Canada 8,100 0.98%

United States Edit

Further information: Dairy industry in the United States

In the United States, the top five dairy states are, in order by total milk production; California,[63] Wisconsin, New York, Idaho, and Texas.[64] Dairy farming is also an important industry in Florida, Minnesota, Ohio and Vermont.[65] There are 40,000 dairy farms in the United States.[66]

Cow Milk Production by State in 2016

After a brief rise following the Great Recession, milk prices crashed again in the late 2010s to well under $3 a gallon at major grocers.

Pennsylvania has 8,500 farms with 555,000 dairy cows. Milk produced in Pennsylvania yields an annual revenue of about US$1.5 billion.[67]

Milk prices collapsed in 2009. Senator Bernie Sanders accused Dean Foods of controlling 40% of the country's milk market. He has requested the United States Department of Justice to pursue an anti-trust investigation.[68] Dean Foods says it buys 15% of the country's raw milk.[69] In 2011, a federal judge approved a settlement of $30 million to 9,000 farmers in the Northeast.[70]

Herd size in the US varies between 1,200 on the West Coast and Southwest, where large farms are commonplace, to roughly 50 in the Midwest and Northeast, where land-base is a significant limiting factor to herd size. The average herd size in the U.S. is about one hundred cows per farm but the median size is 900 cows with 49% of all cows residing on farms of 1000 or more cows.[71]

European Union 

European total milk production in 2009

FAO statistics [62]

(including cow/goat/sheep/buffalo milk)

Rank Country Production (106 kg/y)

   European Union

(all 27 countries) 153,033

1 Germany 28,691

2 France 24,218

3 United Kingdom 13,237

4 Italy 12,836

5 Poland 12,467

6 Netherlands 11,469

7 Spain 7,252

8 Romania 5,809

9 Ireland 5.373

10 Denmark