ANSWERING O c t o b e r 2 0 14 INSIDE THIS ISSUE: Case: Cow injured ... 2 Heifer growing 2 Safe Medications at VETPlus 3 BVD Lockdown Day 3 Drenching Dairy Calves 4 Worksafe NZ 4 OCTOBER The month for: Premating bloods Premating heat recording Non-cycler treatment Bull fertility testing BVD vaccinations Lamb docking SOME QUESTIONS ON BY FANNY LEDUC MILK UREA Milk urea (MU) values are now being supplied to New Zealand dairy farmers by the dairy companies and we are fielding a lot of questions regarding their meaning. Milk urea is an approximate indicator of the amount of crude protein in a cow's diet. The digestion of protein in the rumen releases ammonia. If there is excess ammonia it is absorbed through the rumen wall into the blood stream and converted to urea in the liver. Most of the urea is excreted in the cow’s urine although some passes into the milk. What are normal MU values and what do they mean? Generally in NZ pasture fed cows MU will vary between 20-35mg/dl. High MU values usually reflect excess dietary protein. For example spring grass is very high in protein (up to 25%), when cows in early lactation only require about 18%. This can have environmental implications with nitrogen leaching. There is also a slight energy cost to the cow as she converts and excretes the excess nitrogen. Low MU values can reflect low dietary protein, or an imbalance in the composition and type of protein being supplied to the cows. Low MU values are more likely to be seen in high input systems where grass is a smaller part of the cows’ diet. My herd’s MU results are low/high. What should I do? This will depend on circumstances. Using starch or protein supplements can help balance the cows’ diet and alter MU closer to the normal range. The cost-benefit of instituting such changes must be considered before deciding if they are worthwhile. For more information on MU, you can go to the DairyNZ website and search for “milk urea”, or contact Fanny, Darren or Daniel—your Intelact consultants at VETPlus. PROACTI VE ANIMAL HEALTH PAY S D IVIDENDS - METRICURING RATES DOWN BY DARREN FLORENCE This spring has certainly seen its ups and downs and has been a pretty busy one all round for most farmers and vets. One thing that has stood out this spring is the drop in percentage of cows requiring Metricure treatment to cure reproductive infections. As with anything when it comes to animals and biological systems there has been a range in the percentage of cows infected across the district, we have seen herds with only 2% infected up to the top end of 24% in a couple of cases. We have seen decreases of 5-6% in some herds when compared to last season and we believe this is due to a combination of factors some of which we can do very little about and others that we have a good deal of control over. Weather can often play a big factor and this year it was very positive with ideal calving conditions during a very dry August. Herds on our HEALTHPlus programme were able to pick up early on energy deficits and low Magnesium/Calcium levels as colostrum cows were blood sampled at the beginning of calving. Sorting out DCAD problems early and in particular spraying pastures with anionic salts proved very beneficial in a number of cases. The key message is to identify problems early and sort them out before they can have a negative influence on your herd’s future reproductive performance. If you wish to discuss Metricuring rates on your farm or our HEALTHPlus programme feel free to call at any time to talk to one of our production animal vets. Page 2 CASE: COW INJURED BY BALE SPIKE BY GREG NICKS Recently I was on duty and I got called to see a cow that had been injured after another cow had pushed it onto a round bale spike in the paddock. On inspection there was a large gash on some of the last ribs. One rib had cracked and the small intestine was hanging out of the side. The crack in the rib had opened up, the loop of intestine was outside of it, and the cracked rib had closed again preventing its re-entry back into the abdomen—quite a tricky scenario! The cow was sedated and local anaesthetic applied. The wound was sterilised and an arm entered into the side to inspect the damage. Amazingly the damage was confined to the body wall with little damage internally. The rib was opened up and the intestines carefully returned back inside. The gash was closed in three layers to stop the intestines coming out again and to make sure the rib was held nicely in place. During the operation the calf inside her did a few somersaults just to remind us of its presence! A week later the cow was doing fine and yet to calf. H E I F E R G R O W I N G — H AV E Y O U R H E I F E R S ( R 2 S ) ACHIEVED MATING TARGET WEIGHTS? BY AINSLIE SPEEDY We all know how important it is to be raising high quality herd replacements. Just a quick memo to check R2s are reaching target weights for mating. Breed Friesian Mating Target Weight (start of October) 272kg Weight gain targets per day during October 1.29kg/day Friesian/Jersey cross 249kg 1.12kg/day Jersey 219kg 1kg/day The above targets are based on the Dairy NZ breed targets. These are based on 30%, 60% (aim for mating) and 90% (aim for calving) of the final mature liveweight of the animal at 6, 15 and 22 months of age, respectively. How are mature liveweights established in your herd? There are a few different ways to establish the final mature liveweight in your herd. • Within our grazing business we currently use the following method to create a target line based on Dairy NZ breed target weights. Dairy farmers will supply a MINDA group profile of the mob, a count of the number of Fresian, cross breeds and jerseys in the mob is made and weighted in a calculation which gives us an overall mob breed score. These can be either F, FFJ, FJ, JJR or J. The target line for graphs in our reports are based on these. • Liveweight breeding value can be obtained from MINDA weights. This factors in parentage information which gives an accurate prediction of individual and group liveweight targets. • Weigh milking herd yourself and use this average as the mature liveweight. You should weigh 6-8 year old cows as these cows will be at their mature weight by this age. In spring calving herds the best times to weigh them are December to January or April to May. At this time you should aim to weigh them at BCS 4.5 and the unborn calf will not yet be having a great impact on liveweight. Page 3 V ET P L U S VI B E S SAFE MEDICATIONS AT VETPLUS BY DAVID O’BRIEN At VETPlus we pride ourselves on using medications in animals that have; • Undergone clinical trials to ensure animal and client safety, • Have quality control manufacture, • Have minimal adverse side effects, • Are statistically proven to have the desired effect. Some of the medications in the animal health marketplace have little or no research completed DIRECTLY on the product. VETPlus steer well clear of these products and VETPlus supports the companies that proactively prove and improve their products for the New Zealand farmers and pet owners. To that end, VETPlus has been working for the last 14 months with a manufacturer of animal medications, which has involved • Testing animal and client safety, • Ensuring no side effects, • Statistically proving the product works as desired. The process has involved working closely with the manufacturer, client owners and the New Zealand governing agency: The New Zealand Food and Safety Authority, Agricultural Compounds and Veterinary Medicines department. Just another example of how VETPlus ensures the products we use to medicate your animals are precisely what the doctor ordered. BVD LOCKDOWN DAY BY MAX BAROT There is no understating the importance of having a good control and management plan in place to tackle BVD on your dairy farm. In the hectic period leading up to mating, a BVD “Lockdown Day” is a great way to ensure there are no BVD Persistently Infected (PI) animals in the herd before mating begins. A BVD lockdown day involves a visit from VETPlus where: A Bulk Tank Milk sample is collected from the vat (s) after milking. • Individual testing is carried out on all noncontributing animals (Springer’s, Penicillin mob, pet cows) on the same day. • These samples are then tested for the BVD virus. If your test returns negative, no further action is required. However, remember to keep vigilant to ensure your farm biosecurity is maintained (e.g. bulls tested and vaccinated) and that you have a plan for BVD control and management in the young stock. If your test returns positive for virus (meaning a PI cow is detected to be milking into the vat), then identifying and removing this animal from the herd rapidly is key. In discussion with your VETPlus veterinarian, you can decide on the most effective way to achieve this. In summary, the BVD lockdown day is a cost and time effective method of screening your entire population of adult cows for a possible PI animal. To discuss a BVD lockdown day or any other aspects of BVD control and management, don’t hesitate to give your VETPlus veterinarian a call. Page 4 DRENCHING DAIRY CALVES VETPlus Taupo 07 376 2800 Nukuhau Street Taupo VETPlus Reporoa 07 333 8707 605 Settlers Road Reporoa VETPlus Rural 07 348 9587 181 Old Taupo Road Rotorua VETPlus@SPCA 07 348 9589 24 Old Taupo Road Rotorua 0800 VETPLUS 0800 838 7587 www.vetplus.co.nz WHO, WHAT, WHERE? Sam Taylor from Rolls Peak was recently persuaded to pose for a ‘Huntaway’ shot outside the Taupo clinic. If you find yourself in a situation where young Dairy Calves are being drenched while some are still not fully weaned there are a few precautions to be aware of; Best Practice indicates a combination drench should be used. • Use an oral drench (not an injection or pour on). • Do not use a drench containing the abamectin chemical (i.e. Matrix C, Switch C, Matrix minidose, Converge, Alliance). Once they are at least 120kg and fully weaned then these are the products of choice. • Drench calves individually not in the calfeteria. • Dose the calves accurately (avoid over and under dosing). • Ensure the calves are not dehydrated when drenched. • Check whether the drench contains Selenium (usually labeled as “hi mineral”) and ensure no other source of Selenium is being given at the same time. Oxfen C plus (1ml per 20kg) is a combination drench suitable for young calves, it does contain Selenium. Arrest C (1ml per 10kg) is a combination drench suitable for young calves, it does not contain Selenium. WORKSAFE NZ HAZARD IDENTIFICATION MANAGEMENT PLAN AND BY KARL WEAVER As you are probably aware there is a real emphasis by Worksafe NZ to ensure that rural work places are safe for both employees and contractors. I attended a DairyNZ farm discussion group in the spring and the recommendation by companies such as Hazardco was for farm owners to disseminate this information to all the contractors who visit your farm. To help you met the legislative and regulatory requirements under the Health and Safety Act, if you have completed an assessment of your farm and have identified the potential hazards that have resulted in the creation of a management plan please email it to us ([email protected]). We have a system in VETPlus that will then get the identified risks notified to our staff that would be likely to work on your farm. That way both yours and VETPlus’s obligations in regards to OSH in providing our services to your business are met. Thank you for endeavoring to create a safer work place and forwarding this information to us, it is really appreciated.