Dairy Cattle Production

Hello, in this post we’ll be discussing the dairy industry in Australia. We’ll take a look at the breadth and width of the dairy industry, the general principles of milk production and the common management practices used in this industry.

Over the last thirty or so years, the average annual milk production per cow has risen from about 2800 litres in 1980 to about 5700L now.  This increase in production is mainly a result of improved feed systems and the fact that cows have been bred for a large milk production. Victoria produces about two thirds of Australia’s total milk production with New South Wales producing about 10% of total production and the other states making up the rest.

Supply companies buy milk from farmers and then sell the milk to supermarkets. These companies pay farmers according to the attributes, this includes: milk composition, milk volume, and bulk milk somatic cell count (BMSCC – it is the number of leukocytes in the milk and this indicates inflammation). In terms of composition, the farmers are paid according to the proportions of fat and protein in the milk (with protein being 2.5 times more valuable than fat). Some companies prefer to collect large volumes of milk from producers and so will pay the highest price per litre when collecting over a certain volume of milk. For example, they would pay the most if collecting over 2700 litres). Farmers are also paid the best prices for grade 1 milk (milk with a BMSCC of less than 150,000)

Principles of Milk Production

Before we go on, it is useful to understand some terminology related to milk production first. Cows have to have a calf in order to produce milk. The first milk that a cow produces after calving is known as colostrum and lasts for the first three days after calving. The period of time between calving and when a cow ceases to produce milk is known as lactation. “Days in Milk” (DIM) is the number of days that they cow has been milking during that period of lactation. Cows reach peak milk production 5-8 weeks after calving and then milk production is gradually reduced until no milk is produced. At this point, the cow is called “dry”.

Factors Affecting Milk Production

The amount of milk a cow produces during lactation is dependent on several factors such as:

• The Age of the Cow: annual milk production will increase until the 4^th lactation is reached. After this time, production will plateau out. 
•  Nutrition: It is essential that the cows receive the correct amounts of energy, protein, minerals, vitamins and water. There are three types of feed that can be given to dairy cows:

o   Pasture: this is cost effective but its energy, protein and fibre contents depend on the season. Thus, the farmer ensures that the cows calve at a time of peak pasture production.

o   Concentrates (grains, lupens, etc): these are quite expensive but are high in energy and protein and low in fibre.

o   Conserved Fodder (hay or silage): this is lower in energy and protein and higher in fibre and is moderately cost effective.

• Disease Status: diseases animals produce less milk than healthy ones. 
• Genetics: This plays an important role in increasing milk production. Farmers try to ensure that they retain and breed their best cows to the best bulls available and this can be done through artificial insemination. Offspring are thus genetically superior to their parents.

Overall, happy cows produce the most milk.

Milking

The harvesting of milk can have a large impact on the health of cows and the quality of the milk they produce. The design of laneways which guide the cows from the paddock to the dairy is important for cow health as the animals will need to pass through these four times a day (twice for each milking). Well-designed laneways means that cows spend less energy and time getting to the milking shed.

Milking sheds are also called milking parlours and three types exist:

• Walk through: this is an old style or shed that is used by only a small amount of farmers today. They can be classified as a simple walk through or a step up where cows step up onto a platform. They were designed for milking small numbers of cows. 
• Herringbone: This type of dairy is very common in Australia. They are designed so that on one side of the dairy cows are milked while on the other side cows are exit and enter the shed. 
• Rotary: these are popular with large herds but are expensive to build.

Management Practices

Stock Identification

Stock identification is used to distinguish stock belonging to different farmers, to distinguish between different types of stock and to identify individual cattle. There are several types of identification that can be used:

• Ear Tattoo: there are two types, both are permanent:

o   Registered mark: this ties in with the property’s identification code

o   Code identification of stock.

• Ear Mark: A piece of tissue is removed in a specific pattern or area of the ear. These are also permanent and there are four types:

o   Registered mark

o   Year Mark

o   Animal Type Mark

o   Government Mark

• Ear Tag: This is tied to the National Livestock Identification Scheme. The tags can be made from metal, plastic or rubber and are non-permanent as they can be lost or torn out from the ear. However, they are easier to read than ear tattoos. These tags use machine readable radio frequency identification devices (RFIDs) to identify cattle and the owner’s property identification code is linked to the device.
• Branding: These can be registered brands or stock type brands. Three methods of branding can be used:

o   Hot Iron branding: this is easy to use but is very painful for the animal and permanently damages the hide. It is not used very much in the dairy industry.

o   Acid branding: this is a quick method but chemically burns the skin and may produce bad scarring. Scarring is irritating to the animal and may be difficult to read.

o   Freeze branding: this method doesn’t damage the hide and is less painful. However, hair must be clipped from the brand site and the brand needs to be held in place for thirty seconds. It also can’t be used on white pigmented skin.

Reproduction

There are a few different types of calving systems at use in Australia. The year-round calving method is more common in warmer climates where pasture grows for most of the year and calving occurs for at least ten months of the year. Its advantage is that there is relatively constant milk production throughout the year and this means that there is constant income throughout the year. The disadvantage to this method is that it involves lots of work and the farmer is more restricted in terms of holidays etc. because the cows are always calving.

The seasonal calving method involves cows that all calve at a single period during the year. The benefit to this method is that calving occurs during a short period of time and the farmer is able to take time off during other times of the year.  The disadvantage is that milk production and thus income are not constant throughout the year. There is also considerable pressure during mating time to ensure that all cows become pregnant in a short time. 

In the split calving method, herds calve in two or three distinct time periods each year (for example during autumn and spring). This involves less pressure because there is a greater opportunity for the cows to calve.

Oestrus

Consistent signs of a cow in oestrus include: mounting other cows, standing to be mounted by other cows, hair is rubbed off the back of the cow over the pelvic area. In addition, cows may become restless, bellow more, and produce less milk when in oestrus.

Methods of Mating Cattle

There are three methods used to mate cattle:

• Natural Service: this includes:

o   Paddock mating: the bull is put out with the cows for a specified period of time.

o   Individual Cow Mating: The bull is kept separate from the herd and an individual cow in oestrus is taken to the bull and mated.

•  Artificial Insemination (AI): this is quite a popular method with Australian dairy farmers. Frozen, chilled or fresh semen is used by a trained technician or farmer to inseminate a cow.
•  Combination of Natural Service and AI

That’s it for this post, see you next time :)