2000 June

Pre-milking teat disinfection

Pre-milking teat preparation is widely practiced in Europe and North America. In the US it is a requirement of the food safety legislation. In recent years pre-milking teat disinfection has become more widespread in Australian herds. The application of a teat disinfectant prior to milking may provide some extra control over environmental infections, especially in early lactation. If you are using, or are considering pre-milking teat disinfection there are a few issues that should be considered.

The pre-milking protocols used by the Americans have names like " dip, strip, dry and apply" and the benefits of these protocols are not only due to the application of a disinfectant. The disinfectant solutions act primarily as cleaning agents with the bacteria and debris being removed when the solutions are wiped off prior to cup attachment. The stripping of the quarter permits the fore milk to be examined for evidence of mastitis and stimulates milk ejection, increasing milk flow rates and thereby reducing milking time. The removal of the disinfectant is important. It ensures the teats are clean and dry before the cups are applied, it further stimulates the ejection reflex and it prevents an inhibitory substance (the disinfectant) from contaminating the milk. The products used differ from products applied as post-milking disinfectants. It takes time and effort for the procedure to be done properly. The benefits of pre-milking teat preparation include fewer bacteria delivered into the milk, less bacteria around the teat end, quicker milking, and the identification of infected quarters. It is quite likely that the greatest benefits from pre-milking teat preparation are delivered by the improved milk let down leading to faster, cleaner milking, and the improved detection of clinical mastitis. Most farms in Victoria that employ pre-milking preparation simply spray on their normal teat disinfectant and then apply the cups. Some people are finding that their cell counts and the number of clinical cases have reduced following the adoption of pre-milking spraying. The negatives associated with the practice are numerous. For a start, there are no products in Australia registered for use as a pre-milking disinfectant, and this means that any use of a registered teat disinfectant is "off label". In short, we do not have guidelines for the practice. Secondly, by applying the cups to wet teats, the cups are likely to crawl up the teat reducing the quality of the milking. The presence of emollient in the mix acts as a lubricant and accentuates the cup crawl and may cause cup slip at the end of milking. The liner life may be altered because of exposure to the chemicals in the disinfectants. Finally, by failing to remove the disinfectant before application of the cups you ensure that an inhibitory substance enters the milk vat.

The benefits of pre-milking teat disinfection are greatest when applied to freshly calved cows, in early lactation or any other period when the teats are exposed to high levels of contamination. If iodine is being used it should be applied in a more dilute form than for post-milking disinfection. Emollients should not be added. Ideally, any disinfectant applied before milking is mixed separately from the post-milking product and is wiped off before the cups are applied.

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Preventing lame cows

Lame cows cost you in many ways. Reduced production, decreased fertility, increased culling rates, and the time and cost involved in treating lameness. Apart from these direct costs there are also animal welfare issues and the increased risk of putting antibiotics in the vat. One estimate puts the cost of an average lame cow at $200.

There is currently a good opportunity to lessen the risk of lame cows in your herd. If you noticed your tracks deteriorating with the rains earlier this month, then a little track maintenance now will result in fewer lame cows this season.

The two most important points with your track are to make sure that the middle of the track is raised, so water doesn't sit on it, and to remove high edges on the side of the track so this water can run off easily without pooling on the edge. Ideally the edges of the track should extend under the fence.

Most lameness in cows can be prevented by proper track maintenance and by allowing cows to walk at their own pace along the track.

If cows are left to drift at their own pace they do the following:

They sort themselves into groups with the dominant cows mostly in the middle and front of the mob and the less dominant cows mostly at the back.
Cows avoid touching other cows.
They will keep their heads down, accurately picking a safe place to put their front foot.
The back feet will go in the same place as the front feet.
Cows will tend to follow other cows, often placing their feet in the same places as the one in front.

If you notice the following telltale signs, your herd will be at an increased risk of lameness problems.

Cows at the back of the herd begin to move from one side of the track to the other, rather than follow the cows in front of them
Cows will be seen pushing one another.
Cows will have their heads raised over the back of others.

If you notice these signs, you can make changes to lessen the chances of lame cows.

Move the cows more slowly.
Move cows in smaller mobs.
Improve track surface.
Widen the track.

What makes cows move faster?

It is always very frustrating when cows are reluctant to move through dairy facilities. As the frustration grows, the tendency to force the cows to move also grows. We often resort to shouting, twisting tails, or hitting with polypipe or worse. Does all this help the cows move through quicker or does it just make you feel better? (even if only temporarily).

In a recent Canadian trial, researchers forced cows to walk down a narrow walkway of similar dimensions to a herring bone dairy. All cows passed through the walkway nine times and were exposed to a particular treatment being either shouting, electric shock, hitting, twisting the tail or no interference. The time taken for each pass was measured. The researchers determined that cows found shouting to be just as aversive as electric shocks, and that any interference slowed the progress of cows when compared to no intervention. The findings of this trial quite clearly show that cow flow was best when the cows were not fearful and were permitted to walk at their own pace without interference. The design of the dairy facilities will have an impact on cow flow, however, the way you behave towards your cows can be just as big an influence.

By trying to make the cows move through more quickly, your intervention slows the whole process down.
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Salmonella Update

Recent research performed by the Aus-Vac company has shown some benefits of vaccinating against salmonella. The first benefit is that cows that are fully vaccinated before calving deliver a degree of immunity to the calf through the colostral antibodies. When these calves were exposed to salmonella bacteria they were less likely to become clinically affected than calves that did not receive antibodies. Secondly, vaccinated cows were shown to not shed salmonella organisms in their manure, even when they exhibited signs of clinical salmonellosis. This is an important feature as organisms shed by "carrier" cows act as the source of infection for the rest of the herd. If the level of bacterial shedding can be reduced the spread of infection will theoretically be reduced. Finally, when vaccinated animals were dosed with sufficient salmonella organisms to become sick, they recovered more quickly than unvaccinated animals. It is important to realise this is preliminary research on a small number of animals but the results give some weight to the effect of preventative vaccine. Lately we have seen very few large salmonella out breaks. Many of these are related to such events as upsets in feed intake or balance. This indicates that these cows probably had salmonella present in the gut prior to the outbreak.

As a general recommendation we don't feel salmonella vaccination is a vital component of an animal health program. It is available for anyone who wishes to use it and the above research indicates some protection may be gained. Previous experience tells us that vaccinating in the face of an outbreak does not alter the course of that outbreak.
Clinically affected animals shed large numbers of salmonella bacteria in their milk. If you are treating cows with salmonella, it is advisable that the milk is discarded and NOT fed to calves. It is important to remember that salmonella can infect humans. The control of salmonella is important for the health of your stock and the people on your farm.
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GST Price Effects

All businesses are currently evaluating their businesses to determine the effects of the GST on their pricing structure. For some businesses this is reasonably straightforward, as the goods and services they supply are well documented. The effects of the loss of sales tax has been calculated and a recommended level of price alterations made.

This process is more difficult for us to carry out as our services encompass such a large variation that is not covered in most general business categories. The tax office publishes a calculation tool to enter in costs of the business to get an indication of the GST effects. The result depends on where certain services are categorised. Our result showed that our costs should decrease by 0.05 to 1 percent. We have decided to reduce our prices by 1 per cent in line with the upper end of the loss of sales tax effect. This will mean a saving to our commercial clients of 1 percent and a GST increase effect for non-commercial clients of 9 percent.

It will be interesting to see the effects on pricing of input supplies to the Dairy Industry after 1st July. Those inputs with transport as a major part of their cost will need to be assessed particularly closely. Offices supplies will be reduced in cost quite significantly resulting in an effect on administration backup services to some degree, estimated at about 1.3 percent.

In general prices to the Dairy industry will not alter remarkably due to the GST. Other forces such as supply and demand of feed inputs, labour inputs and world feed and fertiliser prices will be the continuing major influences on farm profitability.
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What will deregulation do to our farm gate price?

There has been much discussion in recent months in the media about the impact of deregulation on the farm gate price of milk. This has been especially directed at NSW, WA and QLD farms where the impact of deregulation will be greater.

Liquid milk sales

In Victoria, prior to deregulation, a continually decreasing percentage (approx. 6%) of our milk has been sold on the liquid milk market, regulated by the VDIA. This has been distributed evenly across all supply factories so that each farm receives an equal percentage share of the liquid milk market.

Deregulation will reduce the price received by factories for this milk purchased by the processors, currently at 46 cents. The processors are then levied 11 cents per litre to fund the package. If the price they pay is 35 cents or less, then there will be no upward rise in the retail milk price attributed to deregulation.

Each milk supply factory, in the deregulated market, will have the opportunity to contract sale of liquid milk to processors. National Foods and Parmelat are the two major liquid milk processing companies in Victoria. The profit from liquid milk sales for each supply company will depend on the price they negotiate with these processors and the volume of sales. If, for example, they double the sales volume, at half the profit margin, then it will not impact on farm gate price.

Given that domestic consumption of liquid milk will not alter significantly post deregulation, then increased market share by a Victorian milk supply company will come at the expense of other supply companies, including interstate. Deregulation will open up state borders and allow supply of domestic milk to northern states from Victoria.

There is a real possibility that the effect on farm gate price could be positive, depending on the marketing ability of your supply company.

The Dairy Market Support Scheme

This legislation was introduced in the mid 1980's by the Commonwealth Government under the Kerin Plan. The DMS levy is on all city milk at 1.9 cents/litre and 3.7 cents/litre on l manufactured milk sold domestically in Australia. It is redistributed to factories on all manufactured milk with the effect of increasing the average milk price by 0.9 cents/litre. In the early days of the scheme, it was at a level which increased the price received for export product by up to 25%.

One of the aims of the scheme was to assist the development of an export component of the dairy industry. This gave the industry the opportunity to expand without the need for quotas. In NSW, QLD and WA, quotas were retained which has lead to the inefficiencies and high cost of production evident in these states today. This is partly contributed to by the high cost of quota and land paid by farmers reflecting the higher farmgate price.

In Victoria, production in excess of liquid milk requirements has not been restrained by a quota system. Instead, supply factories have developed an export industry of world competitive standard. The DMS levy has assisted the development of this market. It has allowed the Australian dairy industry to increase supply by nearly 200% in 15 years predominantly due to growth in the non quota southern states.

The impact of removal of the DMS on Victorian factories after deregulation will depend on the level of export at each factory. Approximately 50% of all Australian milk is currently exported. A company exporting 50% of its milk supply would be in a relatively neutral position since it would receive the same amount of DMS as is levied. Supply factories in NSW and QLD which have a much smaller manufacture component of their milk, have always received less than they have been paid under this scheme.

On July 1st this year when the Commonwealth government removes this legislation, there will be no incentive from Victorian factories to keep out of the city milk market in other states. They will also be able to compete more equitably on the domestic market against importing products from NZ and Europe which have been excluded from the DMS levy.

Other Effects on Price

By far the most significant impact on farm gate price in the next year will be the world market price for milk products. In recent weeks there have been some positive signs for Australia as the Euro has strengthened and supply from Europe has reached quotas.

Provided the $A against the $US remains at relatively low levels, Australian milk companies will have the opportunity to lock into contracts at favourable exchange rates.

Finally, the farm gate price will be influenced by the capability of each company to maximise efficiency of processing. Just as each dairy farm is driven to cost efficiencies, supply factories are faced with similar economic pressures.

The industry does have a positive outlook. For Victorian dairy farmers who have taken on the challenge of efficient production of a quality product, their future in a world competitive industry is optimistic. Murray Goulburn has already set the pace with a strong opening price, up 17 % on last year, reflecting the stronger world prices. This demonstrates the relative insignificance of deregulation on Victorian farm gate prices.

The Other States

To date NSW has still not passed legislation to dismantle state marketing legislation. If, as proposed by the Australian Milk Producers Association, QLD or NSW continue with a quota scheme, even if open to all states, the package under the national Dairy Structural Adjustment Program will not be available to any farmers.

The states have until October to pass this legislation. If they elect to reintroduce quotas, as is being considered by the Queensland premier, it will be in defiance of section 92 of the Australian Constitution. This demands the free trade of all commodities between states. It will potentially invoke a High Court injunction against the state legislation and bring about the same result, that is, full deregulation, but without the package. It would be a brave state government to deny the rest of the Australian Dairy Industry the opportunity to introduce deregulation in an orderly fashion in response to a minority group of farmers attempting who are attempting to retain exclusive access to a domestic market in a society committed to economic rationalism.

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Nitrate Poisoning

In recent year there have been a number of isolated outbreaks of nitrate poisoning in cattle. This year is no exception. Although nitrate poisoning is not common compared with diseases such as salmonella or bloat it can be lethal with significant mortality rates.

The outbreaks are usually associated with grazing of cattle of any age group, on capeweed dominant paddocks. These paddocks are more commonly newly sown pastures with young capeweed or regrowth of a brassica crop. They may or may not have been sprayed to control broadleaf weeds.

Typically the disease occurs when hungry cows are placed in such paddocks in overcast and cool conditions. Nitrate levels in plants appear to be greatest in these conditions, especially following a bout of warm weather. Plants also take up nitrates following long periods of dry weather. This is due to concentration in the roots. Once rains arrive, these are released into the plant leaf material in levels toxic to stock.

Nitrates will convert to nitrites in the rumen if conditions are suited. The nitrites are the active substance causing the disease. Cows will become distressed, and will have laboured breathing. This is accentuated if they are moved. As the symptoms progress, they sit and can quickly die through lack of oxygen. Treatment involves injection of methylene blue into the blood stream. Unless cows are treated quickly losses can be high.

Although there have been cases where to half the animals within a group have died, this is rare. Susceptible paddocks can be grazed with caution, making sure that cattle have had access to hay before or that they are at least not moved into such areas after long periods with out feed.

Long term avoidance of this disease can be through rigorous control of broadleafs early in the season and spraying of crop paddocks before resowing in autumn.

Clinical mastitis rate is ten times higher around calving

The following article is taken from the Countdown Downunder Farm Guidelines.

This publication is available from the office and contains a wealth of practical and accurate advice about mastitis.

A recent study in Victoria showed the incidence of clinical mastitis at calving and for the month after calving was on average 10 times higher than the rest of the lactation.

Cows are very susceptible to udder infections around calving because many of their natural defence mechanisms are low and there is significant contamination of the udder with manure. Some of the worst clinical cases of mastitis occur around the time of calving. Heifers may be particularly susceptible to infection as they tend to spend longer on the ground at calving and often suffer a degree of udder oedema (flag).

Measures taken to reduce exposure to bacteria that cause environmental mastitis (such as Strep uberis and Escherichia coli) are a sound investment for a mastitis control program. They include:

Calve on clean, dry pasture or a clean, dry calving pad.

It is often not the first or second group of animals into the calving area that develop cases, but those that calve there later in the season when the area is not as clean and dry' as it was.

In practical terms a calving area with more than 2 pats of manure per square metre is not clean enough for calving cows. Pasture or calving pads must not be pugged or wet. If water is visible on the surface or in your gumboot prints, it is not dry enough for calving cows either.

Although wet weather in some years makes 'clean and dry' impossible, there will be areas on most farms that are more suitable than others.

Subdividing the calving area, with back fencing of the used parts, can help reduce the exposure to environmental bacteria. If the calving area has a slope on it, using the lower parts first and moving the active area up the slope can also reduce contamination for the later calvers.

Bring cows into the shed as soon as possible - certainly by 24 hours after calving.

Don't allow cows to drip milk. Even if they have NOT calved, bring them into the shed, check their udders and machine milk. To reduce the risk of mastitis it is important to milk udders out completely - using good milking preparation and ensuring milk fever control (diet, calcium treatments etc) is adequate. Similarly, only let calves suckle cows for up to 12 hours, then remove them and machine milk the cow twice daily.

Take special care with induced cows.

Induced cows can be particularly susceptible to infection. Make sure they are kept in clean, dry paddocks after induction, machine milk them as soon as they begin to bag up and watch udders carefully for signs of mastitis.

These measures will help reduce the number of cases of environmental mastitis in your herd during the calving period and reduce the risk of mastitis outbreaks in very wet and muddy seasons.

Timboon Veterinary Group