News From FarmVets SouthWest

August Newsletter

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Please see below a portion of our latest Farm Vets South West Newsletter, to see the whole document please click here:

Farm Vets South West August Newsletter

 

Newsletter August 2010

Dry Bedding and Lying Times

It has been shown that cows prefer lying on

dry bedding, no surprise there really. However,

apart from an increased risk of mastitis,

cows will spend one hour less lying on damp

bedding per day.

It is often heifers who end up forced to use

these cubicles, often in exposed areas or near

broken water troughs etc, and these are the

last animals that need mastitis and lameness.

A heifer that gets a solar ulcer is 4 times

more likely to have it in following lactations

than the average animal.

 

 

Fat Mobilisation and Milk Yield

Cows and heifers that start to mobilise too much fat

before calving are 20% less likely to become pregnant

within 70 days after calving and gave 683Kg

less milk in the following lactation. On milk yield

alone this is a penalty of around £136 per cow.

Excess fat mobilisation is also associated with retained

cleansings, acetonaemia (ketosis), and LDAs.

This can be drastically reduced with good transition

cow management coupled with getting cows back in

calf ASAP so that they do not get fat. Every one will

get a few cows that go stale and put on a few pounds

but if it happens on a herd level then it can become

very costly.

 

 Mastitis and Conception Rates

Clinical mastitis from 14 days before AI to 35 days after it has been shown to reduce conception rates. This effect on conception rates was greater for gram negative infections e.g. e.coli compared to gram positive infections e.g. strep uberis, staph aureus and was particularly severe if mastitis was diagnosed in the week after AI when an 80% drop in the likelihood of AI success was observed. Any sort of handling can stress cows but it is important to have handling areas clean and the cows relaxed in order to stop cows getting more covered in dung than they need be. This can lead to mastitis and if that occurs then you may as well just squirt the semen down the drain.

Clinical Notes

We have seen a few more cases of sudden death in cattle over the last few months. The last case was on a small suckler unit where two calves had died without any signs of illness. Generally, we advise that if clients would like a post-mortem that they take the carcase to the VLA at Langford since taking a fresh,whole carcase is more likely to lead to a diagnosis. In this case one of our vets carried out the PM. The animal had typical signs of clostridial infection plus a very blackened heart. Samples were taken to theVLA and a diagnosis of Blackleg of the heart was arrived at. This is a very rare sort of Blackleg but kills cattle very quickly as does other types of clostridial disease. Vaccination is very cheap, two injections of Covexin 8 or Blackleg can be given six weeks apart and will provide excellent protection.

Johne’s Disease

There is an on going effort to come up with a standard control programme for Johne’s disease. The management practices used are

1) Test all cows for Johne’s disease once yearly

2) Cull strongly positive cows before next calving

3) Separate maternity pens for Johne’s positive cows

4) Use colostrum from negative cows only

5) Remove calves within 2 hours of birth

6) Hygienic collection of colostrum (not left in Orbeseal tubs in the dairy!!)

7) Feeding milk replacer/pasteurised milk until weaning

8) Minimise contact with dung/slurry from older animals especially adults

Points 5 to 7 are generally good management practices and it is no co-incidence that farms that employ Johne’s control practices also have good control of calf scours and early onset pneumonia. If you have a Johne’s problem that testing cattle once yearly or as part of NMR’s Johne’s testing programme is beneficial and allows you to follow all eight points.

However, if you do not wish to enter in to a herd testing programme then the following can be controls can be used:

1) Test suspect individuals e.g. Typically, a thin, sub-fertile cow with poorer yields than expected

and possibly cell count issues

2) Do not re breed strong positives

3) Keep “suspect” or positive cows away from calving areas if practicable

4) Only use colostrum from cows that milked well, got in calf early and are in good body condition.

5) to 8) Follow as above

Events in August

As a change to our usual  Farm Vets South West evening meetings we will be running a few day-time get togethers. The first will be a “Bring a Bag Day”, this will be a chance to have your TMR looked at, as long as you bring a sample along. Feel free to bring a dry cow and milking cow TMR sample. As well as discussing the samples that have been brought along we will visit one or two farms to look at their mix and discuss other factors that impact on dry matter intake such as feed space and timing of delivery as well. This will be a fairly informal day with a limited number of people per day so we hope clients will share ideas and opinions too. Invites containing dates, times and places will be sent out shortly. We plan to

have one Bridgwater day and one Ilminster day.

If this sort of meeting proves popular then we will look to introduce other day time meetings so please

think of some topics that you would like to look at. Each of these meetings will be on-farm and as

practical as possible.

We will also be running a couple of foot trimming courses in the near future too. These will be two

day courses and will cover preventative and curative (lame cows) trimming, bandaging and block

application as well as a bit of theory. The cost of this course is £140 per person attending. There will

only be 4-6 people per course to ensure that practical skills are well honed. Invites to people who have

expressed an interest will be sent out shortly. If you are interested but have not contacted us previously

then please contact any of our three offices.