Feeding Acidified Milk to Calves

There has been a lot of discussion in the farming community in the last month about the use of pasteurisation and acidification of milk to reduce the risk of Mycoplasma bovis (M. bovis) in your herd.  Please be aware that these techniques will not stop M. bovis getting into your calves if it already exists in your herd (i.e. if they have already drunk from their dam).  Pasteurisation or acidification may slow the spread within a group of calves that are fed pooled colostrum, but the status of the group would largely remain unchanged - i.e. positive.

Pasteurisation of milk does kill M. bovis, but a big benefit is a reduction in the load of any Johnes bacteria it may contain.  Pasteurisation is a very good practice for Johnes prevention/control in a problematic herd.

Acidification of calf milk will provide some other health benefits to calves.  Dropping the pH of milk to between 4 and 5, will prevent the overgrowth of E.coli in stored colostrum thus reducing scour risk and increasing the feed conversion ratio (M. bovis will not survive a pH environment of 4 for more than an hour and pH5 for more than 8 hours).

There are two recommended methods for acidification of milk.  The most tried and tested by using yoghurt cultures.  If you use a live Lactobacillus yoghurt culture this will bring down the pH to 4.5.  Start with 2-3L of fresh clean milk and add a live Acidophilus culture and allow to ferment overnight.  The next day mix them into 2 x 20L containers of fresh warm milk and allow to ferment again in a warm environment.  This then acts as a base culture for milk added daily.

The other option is the addition of citric acid - refer to DairyNZ website for instruction on doing this.  The aim is to achieve a milk pH of 4.5.  Calculation and mixing has to be quite precise to avoid milk from clotting or causing calf refusal. 

Potassium sorbate as a preservative, remains as excellent short-term preservative for colostrum.

Lifting Downer Cows

Calving is just around the corner so inevitably there will be down cows.  When you have decided to lift a down cow it has to be effective.  Hip clamps are meant to assist cows to their feet, they aren't for suspending cows in the air.

• Firstly make sure that there is a reasonable chance the cow will stand.  Is she bright and has a bit of go about her?
• Have some padding around the hip clamps, plastic rubber etc.  This is really important when managing a long term downer.  Ensure her skin isn't getting damaged.
• If she is weak/struggling in the front end use a strop under the brisket.  It is good practice to use this anyway.  See diagram:

• If she refuses to stand, stop straight away.  Check your diagnosis, or get help:  Waimate 0800 VET 999, Oamaru 0800 VET 111.
• Keep hip clamps on for a maximum of 10 minutes.  If she has her feet on the ground but not fully weight bearing keep going for a maximum of 5 minutes then stop.
• Whenever cows are in hip clamps they must be supervised.
• Correct placement of hip lifters and brisket strap.

Animal Health Expenditure Review

The use of Restricted Veterinary Medicines (RVM) to both treat and prevent disease and enhance productivity can be viewed as both a cost and an investment.  Based on accurate sales and production data, the average farm in our practice this season spent:

• 8.5c/kgMS in total on all RVMs
• 3c/kgMS on RVMs directly associateed with the treatment of disease - i.e. mastitis, endometritis, lameness etc.

Last year the average Systems 4 farm in NZ had Farm Working Expenses (FWE) of $3.88/kgMS (source - DairyNZ Economic Survey 16-17).  Therefore the average farm in our practice will be spending about 2.2% of FWE on RVMs and 0.8% of FWE RVMs associated with treatment of disease.

A farm's expenditure on RVMs associated with treatment of disease is a good indicator of the large costs associated with disease.  The actual cost of treatment pales in significance when compared to the other direct costs of disease such as reduced milk production, dumped milk, increased culling, empties and labour.  It is estimated that a single case of the following dieases have the associated costs:

• Mastitis - MA cows - $120
• Mastitis - Heifer - $215
• Endometritis - $200-300
• Lame cow - $300-700
• Non-cycling cows - $285

Over the period of the next two months we will be looking to do an Animal Health Expenditure Review with all our clients as part of the annual RVM consult.  The purpose being to identify potential opportunity cost in your business and to identify areas where specific improvements can be made to increase your profitability.

Using Teatseal alone at Last Dry Off

The following data comes from a 1400 cow herd that last season, based on cell count, treated cows with a SCC >150 with Cepravin and the cows with a SCC <150 with Teatseal.

When assessing the effectiveness of a DCT strategy it is the first 1-2 months of lactation that provide the best answers.  The cows that received Teatseal had less than a 5% incidence of mastitis in the first month of lactation.  This is less than our clinic target of 6% and it was also lower than the Cepravin treated cows.  You will also note that the higher SCC cows (Cepravin treated) had a higher incidence for the remainder of the lactation.  High SCC cows from one season tend to be at greater risk of reinfection throughout the next season.  Culling chronically infected cows will mitigate some of this problem.

When offering enough feed doesn't cut it.......

We have just completed the first weights on a mob of poor-doing calves that have been enrolled in the GrowSmart programme by their owner.  The calves, weighed on the 21st March, are currently 41kg behind target, and therefore will need a very aggressive intervention plan if they are to reach industry targets by mating.

The traditional model for "ill-thrift" investigations looks at four main areas that are likely to be involved when animals aren't reaching targets.  In order of importance these are:

1. Nutrition (or lack of)
2. Parasitism
3. Trace Element (deficiencies)
4. Other Disease

These investigations therefore require a holistic approach to the farm and situation.  "Feeding More" isn't always going to solve the problem if the underlying issue is one of parasitism, trace elements, or other disease.

On this farm a combination of factors appear to be involved, however one of the main issues appears to be a very high pasture larval contamination.  The typical picture of larval contamination is a farm that has:

• had a lot of young stock grazing the paddock over a few years
• the calves usually look "wormy" even soon after a drench
• often eating low on the grass sward

Unless addressed, a high pasture larval level will work to decrease growth rates by decreasing voluntary feed intakes (markedly!).

To overcome this, we have opted to use ALPHEUS anti-parasitic capsules in the calves.  These capsules have been on the market for a couple of years now and have shown great promise on these farms with high challenge situations.  The capsules, which have a levamisole and oxfendazole primer and abamectin payload, last 125 days, and are suitable to cattle up to 300kg.  They should kill all incoming larvae on a daily basis, and therefore negate the effects of contaminated pasture.  Alpheus capsules are now competitively priced.

Watch this space - we will re-weigh this mob in another month and see what difference the capsules have had on our ability to properly feed these calves.  If your calves appear to be behind, get in touch with one of our vets ASAP to discuss the holistic GrowSmart package.