Treating Lame Cows over the Dry Period

We are now starting the dry period and the cows are heading away for the winter. It’s time to refresh and hopefully take a well-deserved break.

But even on the best farms there will be a group of lame cows at the end of the season and we must take advantage of the dry period to allow these cows to recover.

I would strongly recommend that any lame cows are treated before drying off and spend the winter on the dairy farm.

Lameness is a clear visible sign that a cow is experiencing pain making this an important animal welfare concern. Lame cows spend less time standing and fail to compete with sound cows at the crop face, resulting in a lower dry matter intake and failure to gain condition over the dry period. Treatment often becomes difficult and unsafe if the grazing block yards and head bail/race are not set up for dealing with lame cows.

Lame cow action list:

• Trim any grossly overgrown claws. One of the most important ways to prevent lameness from occurring during the dry period is a functional hoof trim.

• Review the lame cow mob, chronically lame cows may not respond to treatment and require culling from the herd. A veterinary certificate is an absolute must if lame cows are to be transported to the works. If these cows cannot be certified fit for transport, then a decision needs to be made to destroy on farm.

• Look for any new or mild lameness when cows are being yarded for loading onto the truck.

• Giving a anti-inflammatory when treating lame cows will significantly improve recovery rates. Metacam, Rimadyl or Ketomax are all sound options.

If in doubt about a lame cow seek veterinary advice.

General Principles of Correct Fodder Beet Transition

1. Measure your yield accurately

• This is particularly important for the area that you will be transitioning on. Get an expert to help and make sure DM % is measured at a lab.

• Rows are generally planted 50cm apart so there are usually two rows per metre square. A 25-tonne crop should contain 2.5kgDM/m2 and 1.25kgDM/linear row metre respectively. Note some drills are now planting 45cm rows spaces.

2. Allow at least 1 linear metre/cow along the face of the crop

• The 1m spacing means all cows can reach the face. NOTE -any time a practice leads to variable intakes (i.e. shy cows unable to access crop, dominant cows eating more than there allocation) then you increase the risk of acidosis.

3. Ensure there is a 6m (minimum) to 10m headland that can be used for transitioning

• The headland provides space for cows to access the crop face and turn (important for less dominant cows). Use a beet bucket to harvest bulbs and create a headland. The headland can also act as an area where supplements can be fed.

4. Start at 1kgDM/day and stay there for 3 days until you are sure all cows are eating the beet and then increase by 1kg every second day

• It takes over 14 days to reach intakes of 8-9kg. Cows which have never eaten beet before may take 21 days to achieve this (A true ad-lib intake is 10-12kg -depends on breed size).

• Cows should not enter the crop already full on grass or supplement. Full cows will not eat their allocation allowing others to eat in excess.

• Train cows to stay and eat their allocation before shifting them back to grass. Even if most is eaten in 20 minutes, cows should stay on the break for 2-3 hours so they all learn that they need to eat. Moving the herd onto a new break (on mass) straight after milking works well.

5. Setting your allocation

• Cows can comfortably graze 18 inches under a wire. Set your fence 12 inches back from the row you wish to graze.

• Keep it simple – if you know your tonnage/ha, this will covert to kg/linear metre divided by two. Graze rows lengthwise and calculate the total linear metres required for allocation.

6. Feed a good quality supplement, but do not overfeed this.

• For dry cows, feed about @ 7kg of supplement initially. This should be a good quality supplement (not just Barley straw). Keep the supplement levels up around 7kg until the cows reach around 4kg of beet.

• Once at 5kg of Fodderbeet the supplement can be reduced to 4kg (assuming it’s not just barley straw!). Then keep the FB climbing

• 2-3kg of a hay or straw should be maintained even with cows at max feeding levels.

7. If you find beet remaining after the allocated daily grazing time during the first day 7s, pull back – you are over allocating!

• You typically see the biggest issues with acidosis and deaths at day 7-10 of transition. Cows which have been shy eaters or unable to access the crop face may suddenly take a liking to the crop at the same time as break allocations increase. Their intakes may suddenly rise exceeding the rumens capacity to deal with acid production.

Copper Complacency

Over the last 10-12 years a level of complacency has developed around copper deficiency and the need to supplement. This has come about largely through the feeding of palm kernel. PKE has been a great supplementary feed source and it has the bonus of being high in the trace element copper.

However, the replacement R1’s & R2’s are away from the milking platform where they are fed a mostly pasture or crop-based diet depending on the season. Replacements, therefore, are at far higher risk of developing Cu deficiency than a milking herd being fed PKE through the season.

The extent of this problem was investigated several years ago when our practice conducted some basic surveillance work looking at copper levels in rising two-year-olds at grazing. We found that over 80% of R2 mobs sampled had individual animals deficient in copper.

Before disregarding the need to supplement copper in R1’s and R2’s consider the following points:

• Copper levels are at their lowest in late winter/early spring. This coincides with higher copper demands over this period for late pregnancy and early lactation.

• First calving heifers are often slow to start eating PKE in the shed unless they have been fed it as calves. So, feeding PKE can be an unreliable way of supplementing copper to these animals.

• Humeral fractures are a major issue on individual farms and a significant animal welfare problem. While copper supplementation is not the silver bullet to stopping their occurrence it is a key part of the prevention strategy.

The optimal time to supplement Copper in R1’s and R2’s is mid-late autumn before animals go onto winter crop.

Options to supplement Copper in R1’s and R2’s:

• Coppermax and Copaject injection. This can be safely given to cattle over 4 months of age. A 2ml dose is given under the skin of the neck. The dosage may be increased up to a maximum of 4ml if severe copper deficiency has been confirmed through liver biopsies.

• Copper bullets. These are given orally and contain copper oxide wire particles in gelatine capsules. Typically, a R1 would be given a 10 or 20g capsule and a R2 a 30 or 36g capsule depending on liveweight.

To establish the true copper status of a milking herd 5 liver biopsies are the way to go and we should never assume the copper status of a dairy herd is fine because PKE has been fed during the season. Copper levels will naturally decrease over winter especially if the herd is wintered on crop and the property has no in-line dispenser in the water system.

Whilst blood samples can measure copper levels easily, this only tells us what an animal’s copper status is on an individual day. It unfortunately tells us nothing about the animals’ copper stores in the liver which is of far greater importance going into winter.

Liver biopsies are quickly and easily performed on farm. Whilst collecting liver samples from cull cows at the freezing works is convenient on farm liver biopsies have several advantages.

• The vet is on farm so can select the animals to be biopsied.

• Accurate animal identification at sampling.

• Clear traceability of samples from collection to reporting.

February Production Drop and Heat Stress

For many of our clients (especially those more inland), late January/February saw some significant drops in production. Many farms reported cows being listless and inappetant, despite them going into some good quality feed.

I don’t have to labour the point that this summer has been hot (and humid on many days). For a period there was little reprieve as night temperatures failed to dip below 20 degrees. Friesian cows are comfortable in temperatures less than 20 degrees (Jerseys less than 24 degrees). Above these temperatures cows must work to keep their body temperature under 39.0 degrees.

Cows are essentially a large fermentation tank on legs. The rumen produces a lot of heat. This is great in the winter but in higher summer temperatures it means they will struggle to keep their body temperature low. Night time should provide some reprieve if a cow over-heats during the day, but when temperatures stay high throughout the night they may be starting the new day already in heat stress.

Cows in heat stress will open mouth breath (pant), seek shade and spend more time standing to try to reduce body temperature. Think back to when we had bountiful shelter belts as to where the cows would have been standing on these hot days. Once the body temperature raises above 39.5, cows will be less inclined to eat, will have poor immune function and production and body condition may drop.

We cannot replace tree shelter quickly where it has been lost, but other shorter term strategies may be used.

• Cool drinking water is hugely important. Install multiple water troughs in main lanes to and from the shed.

• Wet down the hot concrete before the cows come on the yard.

• Install sprinklers on the yard (these might be used morning and afternoon if the night was hot).

• Put sprinklers on the shed roof (and/or misters inside the shed).

• Try to avoid milking in the heatof the day.

• Milk smaller herd sizes to minimise the time spent on the yard.

• Let cows move at their own pace – chasing slow cows down the lane will just heat them up more.

Recording Clinical Mastitis Cases

Please record your clinical mastitis cases

The rules are getting more restrictive about being able to use whole herd antibiotic dry cow therapy (DCT). Most of you are steadily transitioning away from whole herd antibiotic DCT and are comfortable with it. However some herds will still require whole herd antibiotic DCT but there are criteria that the Vet Council are expecting us as the authorising vets to have met, to authorise the usage of whole herd antibiotic DCT. Two of the five criteria are based on the incidence rate of clinical mastitis (number of cases per 100 cows). One of these measures is the amount of dry period mastitis – this is traditionally very poorly recorded – if you did have some please record it into MINDA. Even if you are not considering using whole herd antibiotic DCT please get your mastitis records entered in MINDA as this data is also valuable for making decisions at the individual cow level.

To make the best decisions regarding a cow at drying off for selective DCT (is she a high or low risk of having an infection?) we do need data. Herd test data is the best, and the addition of her treatment history (clinical mastitis records) is likely to make a difference to an individual cow. Interestingly the proportion of cows correctly classified does not seem to have altered much (in some papers that have looked at the best decision-making rules) whether mastitis data is included or excluded, but these results are at a population level not for an individual cow. An individual cow is either infected or clean, not 70% infected, so please enter your mastitis data.