South Waikato Veterinary Services

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1 Spring Newsletter South Waikato Veterinary Services Inside this issue: Mating Management 2 At Risk Cows 2 More tips... 3 PenClox Intramammary 3 In Depth Mating Plans 4/5 Calcium & Down Cows 5 DCAD - Does it matter? 7 Listeriosis 7 Dehorning Calves 8 Handy Hints to make spring easier DON T GIVE OXYTOCIN UNTIL THE CALF IS ON THE GROUND 2 HOURS IS MAX - a cow trying to calve any longer has a problem IF IN DOUBT PUT A GLOVE ON - Far easier than dealing with a rotten calving and better for the cow If you assist a cow in calving, give her an injection of 5mL of Oxytocin afterwards. LUBE!! When calving a cow, you can never use too much lube. PROLAPSES THAT ARE DOWN ARE BEST LEFT THAT WAY If she is bright and alert, do not give her any IV metabolics. A prolapse is much easier to replace in a down cow than a standing cow. If however, she is on her side/sick/very depressed, do give an IV treatment. 19 Swanston St, Tokoroa (07) Tirau St, Putaruru (07) SH 30 Whakamaru (07) If you don t currently do whole herd metrichecking (recommended), mark down problem cows and get them checked 4 weeks after calving. Examples are assisted calvings, twins, retained membranes and downer cows. Retained Membranes? We are hearing anecdotal evidence that giving 5ml Oxytocin for a couple of days is helping speed up removal - Try it out and give us a shout if it looks to be working CAN T PICK CALVES UP TWICE A DAY? Take a bucket of Day 1 Colostrum and stomach tube calves in the paddock - a night on a full stomach is a good idea Check out our Colouring in Competition on PAGE 6- Make sure your kids have a go! Entries close end of August. Cool prizes for the winners of each age group.

2 South Waikato Veterinary Services MATING - TWO THINGS TO DO TAILPAINT The use of tailpaint well in advance of mating can not be overstated. Too many farmers rely on watching cows in the yard - one bulling cow can be ridden multiple times by different cows giving the impression of multiple cows bulling - Tailpaint is the only effective method of actually measuring PREMATING HEATS. So - What should you be doing? Tailpaint colours should be getting sorted now - you need at least FOUR colours - ideally FIVE!! Then start by painting cows as they calve and rotating colours EVERY THREE WEEKS. See the in-depth plan on page 5. METRICHECK Metrichecking is the most economical way of finding dirty cows. By dirty we mean cows suffering from ENDOMETRITIS. Endometritis is a low grade infection that causes reduced conception rates. Studies done show cows that are suffering from this take around 10 days longer to get in calf than cows without an infection. Much like noncycling cows, this is a hidden loss - only evident at scanning time as a lower In- C a l f R a t e. Remember that lower In-Calf Rates mean less days in milk which means less $$. What to do with the At Risk Cow Metrichecking is a fast and economical way of checking for Endometritis in an entire herd. However, over calving we will have many cows that for one reason or another are grouped into an At Risk category. What constitutes At Risk? Two easy things - Calving related trouble or metabolic trouble. Should At Risk cows be treated any differently? Some studies have started to crop up that have been looking specifically at the Sensitivity of metrichecking - Metrichecking is by far the best option for finding Endometritis but unfortunately cows with a closed cervix are missed - the pus is trapped inside. The chance of missing cows INCREASES the further after calving they are checked, this is confused with cows becoming clean on their own - self cure rates 2-3 weeks after calving are quite low (1-2% of cows will self cure from then on as opposed to <2 weeks around 30% self cure). So what should you do? Mark At Risk cows and have them checked NO LATER than 4 weeks after calving, this is especially important regarding cows that retain their cleanings - they are at such high risk there is evidence to suggest they should be treated regardless. Page 2

3 Spring Newsletter 20 Tip One - Magnesium Magnesium Sulphate in the water trough rather than Magnesium Chloride Research has shown that it is better than magnesium Chloride in preventing milk fever Its not about the DCAD either!!! Tips!! Tip Two - Calcium Calcium supplementation to the colostrum mob and preferable to end of AB period...limeflour 150g/cow/day or 300 g/cow/day if dusted. Big Tip Three - Monensin The addition of monensin to a cows ration improves rumen energy efficiency...fact Based on the Otorohanga Trial over 245 days -cows produced 230 more litres and 9.8kg additional milk solids. *The Cost is 1.64cents /day over 245 days = $4.01/Cow 7.50 /MS = $73.50 Yes, we sell it BUT the science is there * the 1.64cents /dose is based on our 20% Monensin product we sell...very cost effective.. Speak to Steve on the 20% Monensin product - limited stock available PenClox For the treatment of Mastitis Penclox 1200 is a new intramammary mastitis treatment with two active ingredients included to target all the common types of bacteria that cause mastitis. It is a dual combination of Penicillin and Cloxacillin in one syringe, that has been developed, trialed and tailor -made in New Zealand for our cows. It contains 1gm of Penicillin (like Lactapen) and 200mg of Cloxacillin (like Orbenin LA/Nitroclox) so in theory will treat all the main mastitis pathogens with one tube. This will reduce the risk of treatment failure due to Penicillin resistance or from using the wrong type of antibiotics to begin with. It is generally assumed that most cases of mastitis early in the season are environmental, whilst those later in the season are contagious (cow-cow transfer). However, some farms will have mixed sources of infection early in the season, and that is where t r a d i t i o n a l l y r e c o m m e n d e d treatments for spring mastitis such as Lactapen won t produce an effective cure. So if you are having recurring mastitis cases and have not sent any milk samples in to be tested, reaching for PenClox whilst waiting for culture results would likely be the best option. To find out more give the clinic a call to discuss whether PenClox would be suitable for your farm. Page 3

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5 Spring Newsletter 20 Calcium and Magnesium -fact or fiction Magnesium: is important for maintaining calcium homeostasis. Poor magnesium levels precalving means greater risk of milk fever pre and post calving. Some Magnesium Rules: Cows require around 35g of elemental Magnesium in the month precalving Dust with g Causmag( 45-49% Mg) per cow/day PLUS g Magnesium Sulphate in the water trough is BEST (preferable to Magnesium chloride) a mix of 50:50 Mg SO 4 and MgCl 2 can be used. Post calving magnesium supplementation : Jerseys 15g Mg /cow/day, Friesians 20 g Mg /cow/day. Research has shown that magnesium in the form of magnesium sulphate compared to causmag or magnesium chloride was better at preventing milk fever in cows. Its not the DCAD effect!! The reason why??? Possibly the sulphur component..we don't know Calcium: A surplus of calcium precalving during the precalving period has traditionally been believed to suppress the normal mechanisms controlling calcium absorption. Traditionally we don't feed calcium precalving.but we have had to break that rule on many occasions and have advised the feeding of Gypsum (calcium sulphate) in the springer mobs to prevent precalving milk fever with excellent results. This is not a general recommendation, consult with Steve, Eddy or Vaughan if you have a problem with cows going down precalving or in the colostrum mob. Post calving Milking cows need calcium. Supplement with 150g/cow/day of Limeflour each day (or 300g/day if dusting) for as long as possible..till end of mating Steve recommendation!!! Written REPRODUCTIVE PLANS Like the look of what s on the other page?? That is a comprehensive plan detailing what should be done, and when, for the entire lead-up and first 3 weeks of mating. It includes everything that could be done for a herd trying to improve their reproductive performance and can be tailored to suit what you want done in particular. Any Questions? Call Steve, Vaughan or Eddy at the clinic for a sit down consultation. Too Busy? The crucial feature of most plans is to have tail painted the herd into calving groups based on THREE WEEK BLOCKS. Follow this pattern and we can come in at almost anytime and have a good idea of where to go Page 5

6 Colouring In Competition!! Name:... Age:... Prizes for best drawing (Judged by the Girls) Age categories are <6, 6-9 and >10 Entries due back by the end of August South Waikato Veterinary Services Colouring in Competition Page 6

7 Spring Newsletter 20 DCAD stands for Dietary Cation Anion Difference The theory behind DCAD is that careful diet manipulation of Cations (electrolytes with a positive value - Potassium and Sodium are the big players) and Anions (those with negative values - Chloride and Sulphate are the big players) can decrease the ph of blood - making it more acidic. What use is acidic blood? The main hormone controlling Calcium absorption (from Bones and the gut) is Parathyroid hormone (PTH). There is a marked increase in the sensitivity of tissues to PTH when blood ph drops (From around 7.45 down to 7.35 (A relatively small change in blood ph)). This increased sensitivity helps to gear the cow for the sudden need to absorb a lot more calcium from calving. DCAD - does it matter? So how does playing with DCAD work? To control DCAD effectively it needs to be a NEGATIVE VALUE - reductions in DCAD from 400 down to 200 have little effect on blood ph. This is where we encounter the first problem with DCAD in NZ pasture based systems - Our DCAD IS HUGE. On NZ farms DCAD can vary from around 200 up to The required amount of anions to reduce DCAD to negative values can be up to a kilo of Mag Chloride or Sulphate!! The next problem with DCAD is that it has a relatively short duration of effects - only about 2-3 weeks after getting DCAD below zero the ph of the cows blood will become to normalize - meaning the diet needs to be selectively fed to springing cows only. So does DCAD matter? In short - Not on pasture based dairy farms. What is Listeriosis? Listeriosis is a disease of cattle of all ages that is caused by the bacteria Listeria monocytogenes. This bacteria is found throughout the environment, mainly in soil, and is not considered very pathogenic (compared with something like Salmonella). Infection with Listeria can cause abortions (one of the reasons pregnant women should avoid uncooked salads) and nervous disease - the most common sign. Outbreaks are commonly associated with poorly made silage - normal silage ph is around ph6 which kills off Listeria, poor silage or silage that does not have a have enough sugar content precut will not drop to this point enabling Listeria to live. Listeriosis Nervous disease is associated with the parts of the brain that become infected. The most common parts are those that control balance so the number one sign we see in infected cows is circling, followed by paralysis of one side of the face. So what should you do? If you see a cow with presenting signs like this it is best to call us for a definitive diagnosis. Treatment can be successful but generally only if started early and aggressively Page 7

8 South Waikato Veterinary Services Calf Dehorning 2013 Stress free and painless calf dehorning, as performed by South Waikato Vets for the past 14 years. Calves (ideally 2-6 weeks old) are sedated in their own pens, local anaesthetic is used to dull the nerves to the horn buds and then electric fired disbudding irons are used to cauterize the horn bud. This is the safe and reliable way to dehorn your calves. Stress free & Painless Farmers able to tag ears at the same time Included in the price - we remove extra teats for you Approximately 60 calves an hour! Calves after sedation & local anaesthetic Cost effective 7.17 exc per calf We have our own generator if there is no access to power We can do Ultravac 5 in 1, Salmonella vaccinations & Dectomax worming at the same time All enquiries welcome! No extra teats! What we require from you Calves, preferably between 2-6 weeks of age Fine weather An area for us to sedate them in - clean dry calf sheds or on the yard Access to power (or we can bring the generator) Calves not to be milk fed that morning (if we are dehorning before 12pm) Calves done after 12pm may be milk fed that morning Ideally in groups of calves at a time Page 8