T O W N & C O U N T R Y V E T

July / August 2016 D airy Diary

July / August 2016

WELCOME TO OUR NEW E-NEWS

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What you need to know The calving season is fast approaching, so we want to give you a heads-up on the new regulations taking effect 1 August 2016

Fit for Transport – Age and Physical Characteristics When a young calf is transported for sale or slaughter it must: • be at least four full days old • be healthy and free of any illnesses, Injuries or disabilities • be able to stand and move freely • have firm hooves and a dry and healthy navel.

Twelve hour maximum duration of transport

• A young calf must not be transported for more than 12 hours from farm to its final destination.

YOUNG CALF REGULATIONS

Killing by blunt force trauma except in emergency Circumstances • A young calf must not be transported for more than 12 hours from farm to its final destination. • Calves must not be killed by using blunt force trauma (such as a hammer) except in an emergency situation when there are no other alternatives for humane destruction (such as a

rearm or captive bolt device). This rule will apply to all calves until they are weaned. .

Prohibition of transport by sea across the Cook Strait • Young calves must not be transported by sea across the Cook Strait.

Improved transition cow management has resulted in some of the most significant advances in dairy nutrition and production worldwide over the past 20 years, providing a major opportunity to improve cow health, milk production and reproductive performance. The transition period is defined as the four weeks before and after calving and is characterized by a greatly increased risk of disease as cows adapt to the demands of late-term pregnancy and milk production. When the cow fails to adapt adequately from a non-milking to a milking animal, disease may result. Transition cow diseases include: ● Milk fever ( low calcium) and downer cows ● Grass staggers (low magnesium) ● Ketosis and fatty liver ● Udder oedema ● Abomasal displacement ● Retained foetal membranes (RFM) / metritis ● Poor fertility and poor production

In recent years it has been discovered that all metabolic disfunctions, such as milk fever, grass staggers and ketosis, are linked. As a result of this increased understanding, the concept of transition feeding has evolved from one focused only on the control of milk fever to an integrated, nutritional approach that optimize:

Rumen function Calcium and bone metabolism Energy metabolism Protein metabolism Immune function

Nutritional deficiencies during the transition period will likely affect lactation, animal health and reproductive performance. The transition period is a brief but critically important period in a cows life where careful manipulation of the diet can impact substantially on subsequent health and productivity. In light of this knowledge it seems logical to split your “high risk” springer and colostrum cows from the rest of the herd. Typically, springer cows will struggle to consume their ration in the time that other cows, in earlier stages of pregnancy, are able to. This means that if they are mixed with the herd, they may be at risk of nutritional deficits, right at the time when you want to protect them from disease. Forming a separate springer mob allows these animals access to the best nutrition to consume at their lei-sure. It is also necessary to avoid calcium supplementation to cows in the last 3-4 weeks of gestation as they need to mobilize their own calcium stores pre-calving. In contrast, colostrum cows may require calcium supplementation to meet the demands of early lactation. This is just one example of how the nutritional demands of the springer cows and colostrum cows differ. If you would like any advice on how to best manage the transition period in your cows, have a chat to either Roger or Danny who can help you develop the best plan for your farm.

THE IMPORTANCE OF THE TRANSITION PERIOD

Importance of Early Detection To Clean Up Your Dirty Cows! Endometritis is a chronic, often asymptomatic, infection of the uterus in dairy cows which leads to:

These calving delays mean delays in getting cows back into milk production, meaning lost days in milk and reduced productivity of the farm.

Metricure® is the proven cure for endometritis Endometritis is simple to identify and treat, and New Zealand studies1 have shown that treatment with Metricure® results in significant fertility improvements in at-risk and infected cows. Research has shown that treatment is most effective in cows examined within the first 2 – 3 weeks of the calving period, and treated within 2 – 4 weeks after calving.

Three steps to controlling endometritis: 1. Identify and record all cows that show at-risk factors around calving, and notify your vet. At-risk factors include: retained foetal

membranes, a dead calf within 24 hours of calving, assisted calving, a visible discharge, or cows that had twins.

2. Your vet can then identify infected cows using Metricheck™, a rapid on-the-spot testing device which can diagnose infection by

detecting pus. It is important to check the whole herd to ensure all instances of infection are treated.

3. Ensure at-risk and infected cows are treated with Metricure, the proven inter-uterine antibiotic treatment.

The job’s not done until all at-risk and infected cows have been treated.

July / August 2016 www.tcvet.co.nz

Dehorning Calves For those clients wanting us to dehorn their calves again this year, here are a few reminders that can help to make the job run smoothly.

● Mobs of 30 -40 are a good size

● Best to do when 4 – 8 weeks of age and confined in pens. This helps to cut down the time.

● If they have to be done outside in a paddock a few temporary gates in a corner can help with those few that wander off before

they sit down.

● Don’t feed them on the morning they are to be done, and give them 4 – 5 hours to recover after dehorning before you feed

them.

● If you want to do other jobs such as tagging and vaccinating at the same time, make sure you have an extra worker or two to

help out.

● If any calves are unwell, let us know so we can assess them to see if they are alright to do.

Clinical Evidence Confirms There Are Benefits of Using Metacam® 20 at Dehorning

● Metacam® 20 treated calves had significantly less pain sensitivity at horn buds

● Control calves were almost TWICE as sensitive.

● Metacam® 20 treated calves gained significant more weight over 10 days post dehorning vs placebo.

● The mean difference was 650g / day

Leptospirosis – Vaccination of Young Calves Leptospirosis remains a serious threat to the health and livelihood of farmers. Cases of human leptospirosis have been increasing over the last few years, so there is no room for complacency with this disease. Vaccination has done an excellent job over the last 30 years to protect stock and people alike, but that doesn’t mean that there isn’t room for further improvement in the way that we do things. For example, in spite of widespread vaccination, male dairy farm workers have a 4 to 7 % chance of contracting leptospiro-sis, which is a risk 25 to 50 times higher than the average person in New Zealand. Traditional vaccination programmes in calves have delayed vaccination until around 6 months of age. This has been due to a belief that calves are not at a great risk of infection before 6 months of age and also because of doubts about how effective the original lepto vaccines were when given to very young calves. We now know that calves are at risk of lepto infection well before 6 months of age. If they do become infected they can be-come chronic shedders of leptospirosis in their urine for months or years, presenting a health risk to you any time they are handled. Once they are infected, vaccination is too late to be of any use and will not cure their infection. Calves should be vaccinated early, before they have a chance to become infected. Fortunately there are now vaccines which are effective in young calves, Leptoshield® and Ultravac® 7 in 1 can both be used as early as 4 weeks of age.

PRODUCT OF THE MONTH

FLEXI TUBER

Whether you are bottle feeding, teaching calves to suckle, nursing weak calves or providing essential nutrients through a tube feeder, the Flexi Tuber starter pack has you covered. Every aspect of design has been thoroughly checked by farmers to ensure the smoothest and most practical feeding process for your calves. The right start is critical for your calves, both short term and for longevity, and the right products help you achieve optimum outcomes.

Kinder, Easier, Safer, Faster The Flexi Tuber was developed to solve farmer concerns around calf safety, calf comfort and usability with traditional oesophageal feeders. The Flexi Tuber not only prevents bruising and injury to your calf, it also makes the procedure easier for you. The Antahi Feeder bottle is designed with all of the features requested by farmers to ensure the ultimate ease of use. The Suckle Up cap has a quality Peach Teat for optimum bottle feeding and offers quick transition between nipple and Tuber.

$70 Inc. GST

What’s new for calf rearing in 2016?

The BRIX refractometer- revolutionise your calf rearing There is a new tool for testing colostrum quality. It’s called a Brix refractometer and it looks like this:

Refractometer

AVAILABLE AT TOWN & COUNTRY VET

July / August 2016 www.tcvet.co.nz

The Brix refractometer indirectly measures the antibody concentration in colostrum by refracting light. The more solids (antibodies) in the colostrum, the more light is refracted and the better quality your colostrum is. The Brix refractometer is very easy to use and simply involves placing a small sample of the colostrum onto the slide (as shown above). Much like a microscope, you look through the end of the device; you will see a scale reading of between 0 to 32%. Any sample that reads over 22% is satisfactory; any sample that is under 22% does not contain enough antibodies to make the colostrum suitable for feeding to newborn calves.

Why does it matter if the colostrum sample reads less than 22%? If newborn calves drink pooled colostrum that is under 22% they won’t absorb antibodies into their bloodstream and will be more susceptible to calf hood diseases, in particular- scours. Calves with low blood antibody levels are said to have Failure of Passive Transfer (FPT) and are more likely to get sick and are more likely to die. They also don’t: ● grow as well and struggle to hit target weights ● produce as much milk when they reach the herd as heifers ● get in calf as well as their healthy counterparts The above are all very good reasons to make sure your newborn calves get the best possible colostrum you can feed them at birth. In New Zealand, trial work completed on farms from all over the country last season found that first milking colostrum pooled for feeding to newborn calves was of a very poor quality. In fact, fewer than 10% of the samples we collected measured more than 22% on the Brix refractometer. We therefore have a considerable amount of work to do to improve the quality of pooled colostrum that we feed to our newborn calves in New Zealand!

How do we know if we have a problem with FPT in our calves? Poor colostrum quality often leads to FPT in calves. How do you know if there is a problem on your farm? Ask Roger, Danny or Mitch to take blood samples from 12 healthy calves (when they are between 24 hours old to 7 days old). They will test these calves blood samples for antibody levels to check they have absorbed enough antibodies from colostrum. If more than 2 of your 12 calves have low antibody levels, you should look at the following colostrum management risk factors:

Is your colostrum good quality?

Are you feeding enough colostrum

Are you feeding the colostrum quickly enough? Calves should be fed 10 to 15% of their bodyweight in the first 6 to 12 hours of their birth. Because a calf’s stomach capacity is limited to two li-tres, you will need to split the feed into two. For example, a 40kg calf needs a total of 4 litres of colostrum, split into 2 feeds of 2 litres of colostrum within the first 12 hours of its birth.

How do we improve the antibody level of the colostrum pool for our newborn calves? If you measure the pool of colostrum for newborn calves and it reads under 22% on the Brix refractometer, you should: Check that the colostrum you are adding to the pool for newborn calves is fresh first-milking colostrum (not mixed with days two, three and four colostrum). Try to minimise the time between calving and when the colostrum is first collected from fresh cows; the antibody level declines really quickly the more time that passes. Look at individual cow risk factors for poor quality colostrum; consider testing individual cow colostrum with the Brix refractometer to make sure only the best cows are selected to contribute to the pool. Consider risk factors like age, breed, mastitis and milk fever as possible reasons that an individual cow is not producing colostrum readings over 22%. Even if the antibody level is good, bacteria in the colostrum could be problem. Bacteria in colostrum causes souring and spoilage. Bacteria can also block the absorption of antibodies even if there are enough antibodies in the colostrum. The samples collected from all over New Zealand last season showed that bacterial levels are very high in pooled colostrum for newborn calves. Bacteria typically come from four sources: • the cow; • the test bucket; • the storage vat; • and the feeders. Cleaning all your feeding and storage equipment, as well as minimising contamination from the cow herself is the key to keeping colostrum clean and suitable for feeding to calves. Use hot water and detergent to rinse off the fatty residues left by colostrum and rinse off the detergent fully before using your equipment. Once you are happy that your colostrum is the best possible quality you can achieve, consider preserving it. Five reasons to preserve colostrum: Calves prefer fresh colostrum and find it more palatable than old stinky stuff Antibodies in colostrum are important for passive immunity in newborn calves and decline rapidly under room temperature, if untreated or stored colostrum Antibodies in colostrum are also important to protect against infection at the gut level in older calves (although they won’t be absorbed into the bloodstream in calves more than 24 hours old) Bacterial growth in colostrum prevents antibody absorption in calves Bacterial proliferation in colostrum is unhygienic and leads to rapid spoiling Preserving colostrum Stored colostrum in is often full of bacteria and smells disgusting! Antibody levels in colostrum rapidly decline when it is left sitting around and we need to keep the antibody levels high and the bacteria levels low to feed calves the best possible Colostrum.

How do we preserve colostrum for our calves? Potassium sorbate - a new way to preserve colostrum in New Zealand: Historically we have used a wide range of chemical and probiotic preservatives to preserve colostrum in New Zealand; these include Formalin, Hydrochloric acid and Formic acid. However, the issue with these old compounds is that many of them are not approved for use in the food producing industry and some of them are classed carcinogens. Last season our Cognosco research team completed a study into refrigeration, probiotic yoghurt and a chemical called Potassium sorbate to preserve colostrum. Off the back of this research, there is a new school of thought on colostrum preservation in New Zealand; that is the use of Potassium sorbate. This is a method that has been employed for a number of seasons in the Australian dairy sector to great effect. The chemical has also been approved for use in the food-producing industry for making wine and cheese, and is totally safe for human consumption unlike the acid and formaldehyde based products which have been used in the past. Better still, Potassium sorbate is inexpensive and works extremely effectively to preserve colostrum even at room temperature. Since very few farmers have refrigeration facilities for colostrum storage this means that a bit of potassium sorbate added to the drum can go a long way towards ensuring colostrum stays fresh and doesn’t spoil as readily. Mixing instructions for Potassium sorbate. Potassium sorbate comes in a granulated form and needs to be mixed up as a 50% solution; for example 2.5kg to 5 litres of tap water. Add this 50% solution at a rate of 1% to your colostrum vat; so if you have 500 litres in your drum, you will need 5 litres of Potassium sorbate. Treat each additional volume of colostrum with 1% Potassium sorbate before you add it to your vat. Do not use any Potassium sorbate that has been mixed up for more than a week. Easiyo yoghurt doesn’t work: The latest research from our laboratory showed that Easiyo probiotic yoghurt is not effective at preserving antibody levels in colostrum and preventing bacterial proliferation. The concept of promoting ‘good bugs’ in the colostrum to counteract the ‘bad bugs’ by adding yoghurt has simply been shown to be ineffective; although the practice of adding yoghurt to the colostrum vat has been fashionable for a number of years. Using temperature to preserve colostrum - refrigeration and freezing: Refrigeration and freezing of colostrum to preserve it remains a good option, although facilities may be in short supply. Repeated freezing and thawing of colostrum may lead to denaturing of the large antibody molecules we are so interested in preserving, so it is best to freeze and reheat once only, preferably in a large bucket of boiling water.

Calf Milk Replacer (CMR)

Calf milk replacer post-colostrum feeding is an important part of calves’ diet during their young lives. It is important to be aware of the energy requirements of young calves to ensure that they are adequately met in order to optimise their growth and reach their full potential. Remember, building the foundation for future milk production and reproductive success starts from day one. The energy requirements for maintenance can be easily calculated using the following table: Calf LWT (KG) MJME required/day

25 4.8 35 6.2 40 6.8 50 8.1 60 9.3 70 10.4 80 11.5 90 12.6 100 13.6

Add to this the energy required for growth, which is 11.4 MJME/kg growth and you’ll have the total energy needed per day. For example, a 40 kg Jersey calf gaining 0.8 kg/ day will need 15.9 MJME per day. Use this figure to check current diet adequacy, keeping in mind that the energy content of whole milk is on average 3 MJME/L and for meal it varies generally between 11 to 13 MJME/kg DM. To calculate ME of a product you can use the following formula: ((fat% x 9) + (protein% x 4) + (carbohydrate% x 4)) x 0.4183 There are many different brands of CMR available. There are a few things to consider when selecting which CMR to use: ● Composition of the powder: >19% fat, >24% protein, energy content 20-23 MJME/ kg. ● Good curding is important. The curds are slowly digested into small amounts of fat and protein, which are absorbed.

Poor quality CMRs do not curd. This can be tested by adding 5 ml of rennet to 500 ml of reconstituted milk powder at a temperature

of 40 degrees. After 15 min, milk replacers containing a high proportion of (skim) milk form a good curd. ● Do not change between CMRs during the season, as the differences in fat and protein percentages can upset their

stomachs and cause scours. ● Do not overfeed. ●

Calf rearing is an important yet potentially stressful part of dairy farming with a range of different variables to consider. If you need specialist advice give Roger a ring to discuss your options