Calving Management and Education
On most dairy farms calving is one of the most intensive times of year. It requires a team effort to go smoothly and achieve ideal outcomes. Given the likelihood of staff turnover, the need for annual refreshing and the appearance of new information, precalving training is essential. There is a lot going on at one time, and a great deal to consider if you don’t want to miss anything and want the whole team on the same page.
The key goals of calving time are to:
Ensure most cows deliver their calves without mishap or injury, and start their lactation in good shape, health and nutrition wise.
Secure a good number of heifer replacement calves, starting them off on a good footing to grow well and ultimately become productive members of your future milking herd.
Transition your staff team through a range of “once a year” tasks usually involving extra hours, energy and stress.
Areas which should be covered include:
Feeding and management of transition (springer) cows. When/how will mobs be drafted? What supplements will be fed and by whom? What preventative health measures will we take, such as magnesium supplementation?
Contingencies for adverse weather, especially if continuously wet. How does pasture management and allocation change during wet periods?
Calving cows. How and how often to collect cows and calves? What is your system for calf tagging, colostrum feeding, navel spraying etc? What checks do we conduct on freshly calved cows?
Calving assistance. When do we check cows and who is on the roster. What gear do we have with us, or keep in the paddock. At what point do we assist a cow, and how do we deal with simple assists? Under what circumstances do we call for help, and who do we call? How do we approach metabolic cases?
Calf facilities. These should be organised well in advance, with ample bedding, shelter from prevailing wind, adequate area per calf and reasonable ventilation. Is there a calf scours treatment plan in place, and have you considered prevention, eg vaccination of dry cows?
Calf rearing. How much milk and how often? How many calves per pen, and what other supplements do they get? Who teaches them to drink? When do they go outside? How do we deal with bobby calves?
Cow health management. What are procedures for common diseases, eg retained placenta, mastitis. How do we manage the colostrum mob to find, treat and prevent mastitis? Are we recording disease events, and at what level do we consider them a problem and seek help?
Milking routines and milk quality. Do we have efficient systems in place? What checks and balances do we have to avoid milk quality and antibiotic penalties?
Looking after your staff. Are you sufficiently staffed to cover weekends off? Are employment agreements sorted? Is equipment in good safe working order? Will staff be well fed, oriented and mentored? Do you have smart solutions for heavy lifting?
What a list! Fortunately you don’t have to figure it all out by yourself. The clinic is here to help with advice and expertise, particularly in the areas of herd health and management. We can also put you in touch with good resources, contacts and information sources for any of the areas mentioned above.
Feed Budgeting and Farm Systems Advice
One of the big frustrations we vets find when doing herd fertility work is the uphill battle with cow body condition. If Body Condition Score (BCS) is not up to scratch around calving and mating, herd fertility will never be wonderful.
BCS is the running balance of the “body bank”. Cows withdraw energy during lactation, pregnancy, walking, cold and disease. They gain energy by eating plenty of balanced and quality feeds. In early lactation it is impossible for a cow not to lose condition, so it is best for her to not calve too thin and not lose too much condition between calving and mating.
The InCalf programme has done a lot of work spreading the message of the importance of good BCS. Targets have been set for BCS at pre calving, pre mating, mid lactation and prior to drying off. It’s worth big bucks to have fewer than 15% of your herd either too thin or too fat at the critical times.
Despite this information being freely available, the majority of cows in New Zealand are still too thin at calving. A few are too fat at calving as well. There is a band of “ideal condition” throughout the year that provided cows stay in the zone they will perform extremely well.
Reality Checks
Part of the problem with maintaining good BCS is that people get too close to the action. Spending day in and day out with the same cows and no others can make you “drift” with them. They can be producing plenty and look healthy, but steadily moving away from ideal targets. Without objective scoring tools and/or outside help you will lose your perception eventually. If you are intimately involved with the management of the animals you also start to see what you “should” be seeing, eg if you have increased their feeding you will be looking for an increase and therefore find one.
Sometimes it is quite a “reality check” and a disappointment to find someone qualified scores your cows way lower than you. It means you have probably been below par all year. At other times a qualified person scores them just the same, which is very encouraging.
As dairy health and welfare professionals we pride ourselves on condition scoring cows in an accurate and unbiased way. Getting around lots of different herds helps, and it also helps that we are paid to it, which forces us to do a good job.
We also have some expertise, tools and skills in the clinic to help you achieve your BCS targets. Having health issues sorted is a given, but the most effective advice is related to feeding and feed budgeting. Getting the right feeding levels for sufficient time is critical to reaching BCS goals. We can work out a plan to feed your cows to meet BCS targets on time.
We can also look at your whole farm system and big picture plans to feed the cows optimally all year. This involves feed budgeting and farm setup. Feed budgeting is necessary to ensure adequate feed supply and quality at a good price. We can do simple or complex calculations to suit your approach and pocket. We can also give some advice on fertiliser, agronomy and farm economics; or put you in touch with an expert. As a result you will be able to feed your cows better and more consistently at a very reasonable price, reaping plenty of benefits in production and reproduction.
Milking Management and Efficiency
Improving milking efficiency
Milking cows is the “business end” of dairy farming. It is in the farm dairy that the cows which you have invested in for 2-10 years of their lives pay you back. You have fed and managed them to arrive at the farm dairy today, deliver the product that is going to keep your business financially afloat and (hopefully) make you good money. Successfully extracting quality milk in an efficient, low stress manner is crucial. Get it wrong (such as with an antibiotic violation) and all the other work is wasted.
The average farmer finishing his or her working life after cupping cows for the last 20 years will have put on about one million sets of cups. In modern farm dairies where perhaps one person is cupping 500 cows by themselves on a large rotary the number will be closer to 7 million cuppings in 20 years. This places even greater importance on smoothness, efficiency and sustainability.
Depending on the shed setup and herd size, staff can spend up to 8 hours per day milking. Savings of half an hour night and morning can result in considerable gains to the farm system where that extra hour is available. These sorts of savings are not out of the ordinary if a cow flow or milking efficiency issue is diagnosed and sorted.
Milking efficiency is affected by a big range of factors. How smoothly and quickly do the cows move through the shed? How efficient are the milking machines? Are staff well trained and skilled at working with the cows and managing the various tasks required? Is the rotary platform set at the ideal speed, and what settings are the Automatic Cup Removers on? Fortunately milking management information is more accessible than ever, with programmes such as MilkSmart providing plenty of research done to help us advisors on farm.
If you are frustrated with your milking efficiency or think there’s room to improve, talk to us and we may be able to help.
Milking Management and Mastitis
One area we vets specialise in is mastitis. Mastitis can be environmental, contagious or both. If there is any contagious element this means that infection is passed from cow to cow milking. Milking management is a risk factor in many cases.
If the farm is incurring BMSCC penalties it is imperative we get out on farm as soon as possible and do a milking management visit before more direct financial losses are incurred. In some cases the Milk Processors may sponsor advisory services by reducing financial penalties.
At this “Gradebusting” visit we will help sort out the cows which should be removed from the vat. Samples can be taken and a programme put in place to restore these to the herd when their cell count settles. During this visit we will also assess milking management in relation to mastitis. Teat spraying, cupping technique, general hygiene, teat condition and milking dynamics are all up for examination.
Sometimes we discover short term, easy to fix issues that cost almost nothing to change, for example teat spray technique. Other times the issues may be harder or more expensive to fix, e.g. milking machine equipment problems. These may also require networking with other trained rural professionals. Whatever the root cause(s) of the problem it all starts with a visit to the farm while the cows are being milked. There is no substitute for this “hands-on, real-time” view of your specific situation. It’s the first step in implementing the tailor made solution you need.
Trace Elements – Cobalt, Iodine and Zinc
Cobalt, zinc, iron and manganese deficiencies are less common than copper and selenium deficiencies, but nevertheless can be very important on certain farms.
Cobalt
Cobalt is important in the synthesis of vitamin B12 by rumen microbes. B12 is critical to energy metabolism and growth. Affected cattle slowly develop anorexia, ill thrift, listlessness, rough coat and a watery ocular discharge, even if relatively good feed is offered (eg Bush sickness). Infertility, low milk production, depraved appetite and death may follow.
Deficiency can be diagnosed by soil, feed, serum or liver samples. Sheep are an indicator species; lambs in particular are much more sensitive to cobalt deficiency than cattle.
The cobalt status of soils varies markedly within districts of New Zealand. Recent volcanic soils and coastal calcium sands are among the most commonly deficient. Rapidly growing lush spring pasture has seasonally low levels of cobalt.
Supplementation can either supply inorganic cobalt or organic vitamin B12. Long term, cobalt fertiliser application can raise herd B12 status. Oral supplementation of B12 is useless, as rumen microbes will destroy it, however low concentrations of cobalt in trough water are effective over time. Injectable vitamin B12 is the most effective and practical supplementation in most circumstances, and long acting formulations are available.
Iodine
Like copper, iodine deficiency can result from a simple shortage of dietary iodine or a problem with it’s metabolism. Iodine is essential for thyroid hormone synthesis and many body functions. Clinical iodine deficiency, manifested as a swollen thyroid (goitre) looks like something out of a horror movie. General sluggishness, poor hair and skin condition as well as poor reproductive performance including abortion and births of weak, hairless calves is seen. Newborn calves may have goitre.
Certain crops, such as brassicas and canola have high concentrations of unhelpful goitragens, which interfere with thyroid hormone metabolism. Pregnant cattle grazing high rates of forage brassicas for long periods are therefore at high risk of iodine deficiency.
Sheep are more sensitive to iodine deficiency than cattle.
Iodine deficiency can be diagnosed by serum thyroxine (T4) measurements. However care must be taken, as many conditions such as onset of lactation gastrointestinal parasitism may artificially elevate levels. Blood iodine levels can also be used.
Milk iodine is a reasonable diagnostic, but beware contamination with iodine teatspray!
If the reason for goitre is purely dietary shortage, supplementation is simple via fertiliser or potassium iodide in water. If the situation is more complex, injectable iodine is best. One advantage of this is that the iodine will come out in the milk, benefitting calves.
Iodine toxicity is possible due to over supplementation, and is a human health concern, due to overly high milk concentrations.
Zinc
Zinc deficiency is reasonably rare in Australasian pasture fed herds. Supplementation of zinc is more commonly used as a protective mechanism against facial eczema.
High producing dairy cows have a high demand for zinc, and may experience subclinical deficiency if grazing low zinc forages.
Clinical signs of zinc deficiency include visible deterioration of hair, skin and hooves. There can be poor growth, poor milk performance and male infertility. Subclinical deficiencies can be harder to pin down, but include increased incidence of mastitis and lameness.
Diagnosis can be made through assessment of diet, blood or liver samples. Supplementation is with zinc sulphate, or zinc oxide as either powder or bolus. Toxicity can occur where young animals are overdosed during facial eczema prevention; the signs including anorexia, diarrhoea, excessive drinking/urinating and seizures. Occasionally zinc supplementation can trigger milk fever in adult cows.
Trace Element Deficiencies
Trace elements are minerals which cattle require in very small amounts. By small we mean in the single figure parts per million (ppm) of the diet. That’s not very much, but these minerals punch well above their weight in terms of animal health and performance.
Much of the significance of trace elements has only been discovered in recent decades, and there is still some debate and science being done to define normal ranges and responses to supplementation. In severe cases trace element deficiency can cause clinical disease or even death, but probably more significant is subclinical deficiency, where animals appear normal but are not performing to their potential.
Trace elements are of great interest if you are a farmer seeking to maximise the performance of your herd and reduce herd wastage from disease and infertility. Whether or not trace element deficiency could be an issue for you depends very much on your soil type, but also to some extent on bought in feed and herd management and performance.
Books have been written about trace elements, so we will be very much scratching the surface to summarise some of the common and important ones. The two biggest deficiencies in NZ are copper and selenium.
Copper
Most of the areas where copper deficiency is found have been established, but within areas and even within farms we can get mixtures of soil types so local knowledge is very important.
Copper deficiency can result from either a simple shortage of the mineral in the diet, such as in recent volcanic soils.
Alternatively it can result from an abundance of complexing minerals causing secondary copper deficiency. The deficiency happens when dietary copper is bound to the likes of iron and molybdenum in the rumen, making it unavailable to the animal. This secondary type of deficiency was recognised in cases of "peat scours” in the 1940s on peat soils.
There is a seasonal reduction in copper availability from spring pastures (when sulphur levels are high) and when soil (and therefore Iron and Manganese) levels ingested are high in wet conditions.
Combining this with the high copper demand from pregnant cows and growing yearling calves and we see most copper deficiency in these high risk groups in late winter through to the end of spring.
Zinc can be a direct antagonist to copper, secondary deficiencies arising when zinc supplementation is heavy during facial eczema control periods.
Clinical copper deficiency can result in ill thrift, immunosuppression, anaemia, falling disease (heart attack), peat scours and ligament/bone disease including fractures. Subclinically growth rates and milk production are affected. Black hair appears more red.
Copper is stored in the liver and circulates in blood enzymes. Blood tests give us current working levels but liver biopsies give us information on copper reserves. Both are important measures and apply at different times. If we test your herd we can customise an action plan to avoid deficiency.
Copper can be supplemented by many different routes, mainly orally. Copper drenches can be given or water troughs treated with a soluble supplement. Mineral supplements can be added to feed, or feeds high in copper (such as palm kernel) can contribute to the “copper budget”. Copper needles can be given as a bolus capsule, copper can be injected or pasture can be topdressed. The best supplementation depends on the reason for the deficiency (primary or secondary), the depth of the deficiency and the way the animals are being managed.
Occasionally accidental or overzealous supplementation can result in copper overload, toxicity and rapid death. The liver struggles to contain and process the copper, effectively nuking it’s cells.
Selenium
Selenium is the essential antioxidant trace element. Unlike copper, the deficiency mechanism is simple. Deficient soil, deficient pasture, deficient animals. By world standards the whole food chains in Australasia are short of selenium, but we seem to only see the effects and responses to supplementation when we are very short.
The signs of selenium deficiency are associated with cell damage. This can be heart and muscle groups, such as in fatal white muscle disease or it can affect immune function (immune cells). Ill thrift in young growing cattle and poor milk production and fertility in cow herds are the most common subclinical effects. Other less common signs are retained foetal membranes (RFM), subclinical mastitis, perinatal calf mortality and abortion and anaemia.
Selenium deficiency is widespread in New Zealand and can be diagnosed from feed tests, blood, animal tissues such as liver and soil tests. Response to treatment may also be considered a diagnostic, and treatment is cost effective.
Supplementation can arrive in fertiliser on pasture, water systems, feed additives, intraruminal pellets, drench and injection.
Overdosing with selenium can cause rapid and violent death where the dose is high. Long term over supplementation can cause chronic selenium toxicity resulting in weight loss, hair loss and hoof damage.
If you are considering supplementation with trace elements or diagnosing your status, sit down with us to work out a smart plan. It is easy to waste money on trace elements, so talking to us before you do much is a very good investment.
