Reducing Disease & Deaths in Newborn Calves

There is nothing more demoralizing than a pen of sick and dying calves. This frustration is even greater when you appear to have done all of the right things; cleaned out pens, vaccinated the cows, fed high grade colostrum, isolated sick calves, and so on!!

A recent New Zealand trial looks to have shown a potential new tool for these situations. The trial looked at the effects of giving calves a 0.75ml injection of MultiMin within 24 hours post birth. MultiMin contains zinc, manganese, selenium, copper, and chromium. Overseas studies had previously shown reductions in disease and mortality after supplementation at this stage, and this trial backed up these findings.

This trial showed marked reductions in disease morbidity and mortality between 3 and 35 post calving, with the MultiMin group having a 66% reduction in the odds of scouring in that period compared to the control group. At this stage the mechanism of action is unknown, but it is likely that there is a direct effect on the immune system. There are plenty of articles looking at the involvement of zinc and copper in immune function, and other trials with MultiMin in challenge situations with BVD that showed faster rises in antibody levels in calves given MultiMin.

Treating calves with MultiMin could be incorporated into the daily routine, with calves being injected as they arrive in the shed, and give your newest arrivals the best start in life.

Getting Cows to Targeted BCS by Calving

Getting cows to an optimal BCS by their calving date is a key requirement to achieve good cow health, productivity and reproduction in the following lactation.

The target is to get the greater majority (>70%) of cows to BCS 5.0 and R2 and R3’s to BCS 5.5.

Although monitoring the herd average is important, just as important is the shape of the herd profile. Having too many light or fat cows will have negative outcomes at a herd level.

Where a wide range in BCS exists, we recommend that cows be wintered for the month of June based on BCS. Given that many crop yields are a little shy of target this year it is good to identify light cows for preferential feeding and hold back those that have already reached or exceeded target BCS.

Ideally cows will have reached target BCS by mid-July and they can be then drafted into groups based on ‘due to calve date’.

Regular monitoring is the only way to ensure that you are on track. We recommend getting a baseline score on the cows after dry-off when cows first arrive at the winter grazing block. A calculated required dry matter intake can then be derived from the current BCS and worked on a winter feed budget. Key monitoring dates are around the start of June, 20th of June and 10th of July. Contact your prime vet for more details.

General Principles of Fodder Beet Transition

a) Measure your yield accurately - once you know the yield/ha (i.e. 25 tonne/ha crop), you can calculate your yield per square (two rows per metre square) and yield per linear row metre. This would be 2.5kgDM/m2 and 1.25kgDM/linear row metre respectively.

b) Allow at least 1 linear metre/cow at the crop face and at least 5m2 of turning room in the first break.

c) Either drop wires on the permanent fence in the first break to allow a bigger area of scrape bulbs with a front end loader (and feed in paddock or stock pile) to create a headland.

d) Best to calculate offering in linear metres to be fed, i.e. if offering 3kg a cow from a 30 tonne crop this would be 2 linear metres or 1 square metre. To be accurate you will have to offer part rows - i.e. your live strand will have a dog leg in it at some point.

e) Cows will comfortably graze 18 inches under a single strand wire. Make sure that the wire sits back 12 inches from the row you are looking to graze. It must be very high voltage!

f) Always feed your supplement or grass first and give a gap of 2hrs before shifting onto break.

g) For the first couple of days drive over bulbs with tractor tyres to break up bulbs to get cows eating it.

h) Start at 1-2kgDM/day and increase intakes by 1kgDM every second day until transitioned (7kgDM). This takes a minimum of 14 days. Once cows have reached intakes of 7kgDM FB they are unlikely to suffer acidosis but further intakes up to 10-11kgDM total (ad-lib) must still occur at 1kg every second day.

i) Lactating cows (500kg) in most situations should max out at 5kgDM/day of fodder beet (start at 1-2kg). Larger breeds may get up to 6kgDM.

j) If you are going to get acidosis this tends to occur at days 7-10!! It is critical to remain restrained with allocation over this time. Do not let beet bulbs accumulate while still shifting breaks forward.

Once cows have got above 10kgDM/day and looking to ad-lib feed there should be 15-20% of beet left from the previous day when shifting wire and about 5% from the previous day before that. Cows will always eventually clean this up.

Top Reasons Why Your Drench Program Didn't Work

Every summer/autumn we see numerous lines of calves that have suffered poor growth rates and/or shown signs of clinical parasites.

Calves that are ‘loose’ (dirty tails) despite grazing on high dry matter feeds, ‘wormy’ smelling faeces, and coughing may be all indicators.

Here are some of the reasons why parasites may be an issue:

The drench interval was too long in the current season

• Most worm species take 3 weeks to mature and start laying eggs. If the interval between the end of the activity period of the drench extends more than 3-4 weeks eggs and larvae will build up on pasture.

• A key part of a drench programme is to return for next drench before worm eggs in faeces become numerous.

Product selection did not suit the situation

• Oral drenches have no persistent activity - as do most solvent based pour-on products.

• Where high worm pressure is suspected either reduce the drench interval, or use proven long acting pour-on products or consider drench bolus (capsules).

There was a high pre-existing worm larvae load on your pasture from the previous season, meaning calves were always being challenged.

• Every mouthful of dry matter that is high in larvae will reduce appetite and therefore DM intake and weight gain.

• It is important to work in with other graziers on a property to ensure everyone works together every year to keep the pasture larval load limited.

Be aware of climatic conditions

• There is often mass emergence from dung piles after extended dry periods when the weather breaks.

• Conversely with extended warm, wet, humid conditions, larval survival will be aided, this could increase the challenge by more than 10 times!

Vet Certification for Transport

As the mating season concludes many farms will be looking to offload bulls and start making decisions over cull cows. It is during this time we see an increased requirement for veterinary transport certificates. It is a legal requirement that animals are fit for transport. The certificate remains valid for 7 days from the date of examination and the animal must be slaughtered at the nearest processing plant.

What we need from you:

• An area to adequately examine and restrain the animal when required

• The animal tagged with a recordable number for identification

• The location of the processing plant and when killing space has been booked.

From a veterinary point of view:

Due to increased scrutiny being placed on transport certificates by MPI, there is strict criteria that we as veterinarians must follow. Below are common conditions requiring certification and the associated requirements.

Penile conditions: Bulls must be able to urinate freely, not have any haemorrhage, swelling, abscessation or discharge from the area surrounding the penis.

Cancer eye: the cancer cannot be larger than a $1 coin (2cm), confined to the eye of eyelid (not spreading), not bleeding or discharging pus.

Lameness: Great emphasis is now being placed on lame animals being transported for slaughter. Lameness is scored 0-3. Grade 2 animals may be certified fit for transport with specific instructions such as reduced pen density. The link below is the Dairy NZ lameness scoring system and I strongly encourage all farmers to view the following video to assess whether the animal is a suitable candidate for certification.

https://www.dairynz.co.nz/animal/cow-health/lameness/lameness-scoring