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HFV News MAY 2021

In this issue…

  • BEWARE: Staggers risk
  • Milk fed calves - how are yours performing?
  • BVDFree - do you qualify for Test Negative Status?
  • Medicines Update
  • HFV - a year on!

BEWARE: Staggers Risk

This recent rain will bring about a welcome flush of grass growth - this fast growing grass tends to be low in magnesium and low in fibre so it passes quickly through her guts before the mag can be absorbed. There are no stores of magnesium in the body for the cow - she gets all she needs from what she eats every day so the next few weeks will be a challenging time for mag availability.

What does staggers look like?

  • initially odd neurological signs: high head carriage, twitching muscles, appears blind, staggering and paddling
  • quickly becomes a flat out cow, paddling, fitting and sweating - these are dangerous animals to go near so PLEASE be careful in handling or treating a possible staggers

Sadly, often the first thing you see is a dead cow, so if you are worried about a possible staggers - you need to act fast; it is one of the true veterinary emergencies.

How do we treat it?

Safety here is VITAL - a thrashing, flat out cow can be a very risky patient.

We need to get blood levels of magesium back up as quickly as possible - but magnesium can kill a cow if you give too much into the vein.

In mild to moderate cases we would recommend a bottle of calcium into the vein if you can restrain her safely enough, and a bottle of magnesium under the skin but sometimes they are thrashing so madly that it is an emergency vet job and we need to sedate them and give muscle relaxants before we can treat them.

What can we do to prevent staggers?

  1. Buffer feed with extra roughage to slow down the grass passing through the guts
  2. Supplement with additional magnesium during high risk periods.

Mag licks are convenient but it doesn't guarantee every cow has had enough.

Mineralised concentrates can help to make sure every cow is supplemented but not all cows need extra energy from concentrate at this time of year.

Rumen boluses guarantee every animal is protected but they are labour intensive.

Mag salts can be added to the water supply which is quick and easy but it's pretty unpalatable for the cows so make sure there are no other water sources.

Milk Fed Calves - how well are yours performing?

Aiming to calve well grown heifers at 24 months old is going to become ever more important for farm efficiency and plays a massive role in your farms carbon footprint for the future.

Did you know? Heifers that calve at 22-24 months old outperform later calving animals in terms of fertility, milk production and survival over their first 5 years of life.

Calving at 24 months old is only successful when growth rates are consistently over 0.8kg/day from birth to weaning, weaning to service and through pregnancy to calving. The average age at first calving in the UK is still 28 months old - dropping that by just 2 months would save £66/heifer reared.

Feed Conversion Efficiency (FCE) in heifers:

The feed conversion rate of newborn calves is the best of their whole life; for every 100g of feed you put in, they can convert it to 50-60g of growth. This drops off after weaning and by the time she is 8 months old 100g of feed only creates 9g of growth.

This window of maximum FCE can make all the difference to heifers - restricting milk replacer to 2 litres twice a day just doesn't give them enough nutrients to grow to their potential. When you push growth rates and feed higher volumes of milk (>3 litres, twice a day at 125g powder per litre) you may have to work a bit harder to get them eating enough concentrate ready for weaning and this tends to mean weaning is delayed and staged.

Whole milk performs differently to milk replacer so you can hit the same maximum growth rates using lower volumes of whole milk, especially with high milk solids. It goes without saying; pasteurised whole milk is best practice, or you will need strict in-parlour protocols for any "ever a positive" Johne's cows to reduce the risk of spreading Johne's disease.

Even though it might seem baby calves aren't taking much concentrate, or straw, or water in the first few days and weeks - all 3 of these are critical for starting the development of the rumen - a process that takes 6 weeks and is key to a successful weaning.

The Rumen:

The rumen in an adult cow is a massive 150 litre vat of bacterial soup that breaks down the diet into energy and protein that the cow can absorb. As you know, the rumen bacteria and the rumen surface take weeks to respond to a diet change in an adult and if something suddenly changes with her diet then her performance nose dives - and this is no different for a calf.

When a calf is born the rumen is small, it's muscles are weak, it has very little blood supply and no capacity to absorb nutrients - milk bypasses it and goes straight into the abomasum. It is the gradual trickle of nibbled concentrate and straw as well as water in those first few weeks that feeds the right bacteria into the rumen and kick starts the surface changes that mean the rumen can start to absorb food ready for weaning.

The following photos show what the inside of a rumen looks like in calves at 6 weeks old depending on different feeding regimes:

MILK ONLY:

The surface is pale, smooth and weak - this rumen has no capacity to absorb nutrients.

MILK + HAY:

You can see some development of the muscles and surface so this calf would be able to absorb some nutrients from the rumen.

MILK + STRAW + CONCENTRATES:

This rumen has developed strong muscles, the surface is highly developed to absorb the nutrients and the darker colour shows how much blood is at the surface ready to take the nutrients to the liver for processing. This calf would sail through weaning.

If you wean a calf before her rumen is ready to feed her then her growth will stall, her immunity will take a hit and the chance of weaning diseases spiral (cocci, pneumonia, ringworm).

Weaning:

The only thing that should change at weaning is the final reduction in milk volume over that last week; no vaccinations, no disbudding, no mixing groups, no moving sheds, no change to the concentrate or protein source. If the rumen has been well prepared, it just continues to process and digest the increasing amount of solid feed so there is no dip in available nutrients to the calf.

Weaning should only ever take place when the SMALLEST in the group is eating 2kg concentrate a day for 3 days in a row.

Targets:

Monitoring growth rates in young calves doesn't need to be complicated - a weigh band works fine and you don't need to weigh every calf - just follow a few heifers from each batch if you calve all year round, or a few heifers from each week of the block whilst your heifers are being born. The same calves should be followed over time - at a minimum you will need a birth weight, a 4 week weight and a before and after weaning weight to cover the early life growth rates.

Target growth rate: 0.8kg/day
Weaning weight: at least double birth weight

Get in touch with Paula or Tom if you would like to to track growth rates and health parameters in replacement heifers.

BVDFree England - do you have Test Negative Status?

BVD is one of the costliest diseases affecting the UK livestock industry. Most of you are signed up either to BVDFree England or a BVD CHeCS accreditation program - these aim to get you BVD free by a combination of strict biosecurity and disease surveillance. This also forms the basis of your BVD health plan; which is now part of your farm assurance for dairy farms, and will be part of beef HHP from October.

If you have your first two years of BVD free testing completed (either virus or antibody), and all the results are negative and uploaded to BVDFree, you can download the "BVDFree Test Negative" form from their website and get BVDFree Test Negative status. For any of you selling stock either through markets or privately, this "Test Negative" status proves your herd is BVD free and will become increasingly valuable over time.

Once you are "Test Negative" we then repeat your ongoing youngstock monitoring, get your negative test results uploaded to the BVDFree website and your herd status is renewed each year.

Make sure Haywood Farm Vets are your selected vet practice on your BVDFree login so we can keep a track of results too.

Medicines Update:

MULTIMIN: meat withdrawal

Multimin is a potent multivitamin that provides a targeted boost of selenium, copper, manganese and zinc. With immediate effect the meat withdrawals have increased from 8 days to 28 days. This increase comes into effect regardless of what is printed on the label for the Multimin you may have in stock.

Trymox LA: milk withdrawal changes

Trymox LA is a long acting preparation of amoxicillin used as a first line treatment at some of your farms. The milk withdrawal has increased from 84 hours to 108 hours. This change does NOT come into effect immediately - but will be phased in with new stock so just follow the withdrawals on the labels and we will let you know when the withdrawal comes into effect.

HFV - a year on!

May 5th is a bit of a milestone for us as we celebrate our first 12 months as HFV!

Paula & Tom would like to take this opportunity to thank you all for your support over the last year; for your confidence in us, for the conversations we have, for the feedback you give, for the way you run your farms and for what we have achieved working together with you all.

We will keep HFV local, personal, experienced and independent!

We're very much looking forward to COVID restrictions easing and perhaps seeing you down at The Wharf for a few drinks in the very near future! Watch this space...

GET IN TOUCH:

Paula: 07764 747855 paula@haywoodfarmvets.com

Tom: 07837 291097 tom@haywoodfarmvets.com

Enquiries: mail@haywoodfarmvets.com

Website: haywoodfarmvets.com

Open hours: M-F 08:30 - 16:30

Out of Hours: 07398 743095

Created By
Paula Scales
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