Haywood Farm Vets Newsletter november 2024

BOVILIS CRYPTIUM - new Crypto vaccine

Crypto is a disease in calves caused by the parasite Cryptosporidium parvum that can lead to severe diarrhoea, dehydration, and death. It's one of the most common causes of calf diarrhoea, especially in calves that are 7 to 21 days old and is the most common reason for deaths in calves under 1 month old.

Historically Crypto control has been focussed on hygiene in the calving yard, hygiene in calf pens, making sure the calf has good levels of immunity from colostrum and a bit of "cross your fingers"! It tends to be a disease of accumulation so you get breakthrough cases when calving yards get busy or you get a bit blocked up in calf pens or staffing is a bit tight.

Infected calves shed millions of the parasite eggs in every gram of scour and it only takes 17 Crypto eggs to cause infection in a calf, so spread is almost inevitable in group housing. These eggs survive for months in the environment and are only killed by a few disinfectants that can break down the tough outer coat (Cyclex, Coxicur, Kenocox)

There are daily oral drenches "Kriptazen" or "Halocur" that can be used from day 1 which reduce the infection risk and shedding level of Crypto from infected calves but these medicines only reduce the severity of disease, don't prevent it entirely.

Bovilis Cryptium

Bovilis Cryptium is a new vaccine from MSD that boosts the immunity in the cows colostrum to a protein on the Crypto parasite called Gp40. This means that feeding the colostrum from vaccinated cows to young calves prevents infections happening as the antibodies in the colostrum attach directly to the Crypto parasite and stop in entering the gut cells in the calf. The antibodies produced by the vaccine neutralise the adult parasite as well as 4 other immature stages - this means all stages of the Crypto lifecycle are blocked.

Colostrum Feeding

Bovilis Cryptium works by boosting levels of Gp40 in the milk of freshly calved cows - this boosted milk needs to be fed for a minimum of 5 days for the calves to have full protection.

5 days whole milk feeding and Johne's risk:

Some of you may be concerned about feeding colostrum beyond the first 2-3 feeds because of Johne's risk from the cow. The risk of milk is highest from clinically affected Johne's scouring cows - but as always, the risk of muck contamination of milk is the bigger risk.

There are huge benefits to feeding colostrum beyond the first 2-3 feeds - we're only just starting to understand what's in colostrum - it contains much more than just immunity!

There are sensible precautions you can take to reduce the Johne's risk of feeding colostrum for 5 days if you're worried:

• make sure medium, as well as high risk Johne's cows are served to beef so your heifer calves are born from your safest cows with the lowest risk colostrum
• do a full parlour routine for collecting colostrum so any bacteria on teats are removed before milking to reduce the risk of contamination (strip, dip, wipe, cup on)
• colostrum needs to be collected and stored in lidded buckets so muck splashes can't contaminate the milk
• you can use 0.5% Potassium sorbate (a food preservative) to reduce bacterial growth in colostrum - but remember this only reduces growth so the colostrum still needs to be collected cleanly
• a pasteuriser massively reduces the risk of Johne's bugs surviving in the milk and would be an obvious solution

Dose: 2ml under the skin

Year 1: 2 doses, 4 weeks apart, 3-12 weeks before calving

Booster dose: 1 dose 3-12 weeks before calving

VAN - is yours due for renewal?

If you are not farm assured, and are selling cattle or sheep fat, you will need a "Veterinary Attestation Number" - a number of these are coming up to their 12 months renewal so make sure you get in touch so we can get these sorted in plenty of time.

MEDS UPDATE

A few vaccine related updates this month. Making sure we protect you from outages, supply issues and communicate any essential changes is an important part of what we do at HFV.

Heptavac-P update:

There are supply issues with Heptavac-P again this season - the supply of 25 dose and 125 dose bottles looks unlikely this season due to manufacturing problems, but there will be (limited) stock of 50 dose and 250 dose bottles.

We will have stock coming in the next few weeks and again in Jan, so we will be in touch with all our vaccinated farms who have confirmed orders with an update as soon as your vaccine arrives.

There are alternative vaccines available; none are like for like with Heptavac-P but we can still get you Clostridial and Pasteurella protection to cover lambing time if these stock issues continue.

Fencovis

Fencovis is our new scour vaccine to give cattle before calving to boost immunity against E coli, Rotavirus and Coronavirus - the three main causes of calf scour in the first week of life. It is the first scour vaccine to have a full prevention claim against E coli and Rotavirus, as well as reducing the severity of scour caused by Coronavirus.

Dose: 2ml IM 3-12 weeks before calving

Note - this is a different dose to our previous scour vaccine so make sure you let everyone know to reduce the dose to 2ml

Pack sizes:

• individual doses x10
• 5 dose bottle
• 25 dose bottle

Vaccine reactions: Fencovis is much less reactive than some of the other scour vaccines on the market so there should be far fewer lumps and bumps post-vaccine.

Extended colostrum feeding: All the scour vaccines work best if the boosted milk is fed beyond the first few colostrum feeds. The antibody levels remain high for weeks in the transition milk and continue to "mop up" bugs in the calves gut which prevents scour during those first few weeks.

"Cascade Use" - a reminder about what it means

The cascade is a legal, risk-based decision tree that allows vets to prescribe medicines that are not authorised for a given species, or for a given condition or when there are problems with supply and we have to import meds. Cascade use is legally a vet only decision, and we have got to document it and record it at our end for each individual treatment as well as setting different meat and milk withdrawals.

Examples of cascade use:

• Extending a course of lactating cow tubes by an extra day
• Extending a course of antibiotics beyond the 3 days that is on the leaflet
• Using an antibiotic for sheep that is only licensed in cattle
• Using a bigger dose than what is on the leaflet
• Putting a medicine licensed for under the skin into the muscle

As you know, the vast majority of treatments used on farm won't be cascade use as they will be as per your agreed protocols, and as per the instructions on the leaflet and so these treatments just need recording at your end as normal. If you are struggling with a case and need some advice about what to do next, just make sure you speak to your vet so we can keep treatments safe, legal and keep our records up to date at this end.