Cambridge Veterinary Services Golf Day 2013

Transcription

1 June 2013 Cambridge Veterinary Services Golf Day 2013 STOCK SENSE CLASSES Cambridge Vets are now trained up and eager to teach new farm employees the introductory Stock Sense course. This is a half-day teaching session set up by DairyNZ, which means it is free to levypaying farmers. It covers how to spot and report sick cows and lame cows, and other important practical skills. This course will be run on the 1 st of July, and will be restricted to people. Phone the clinic to book in any new workers. Spaces are limited to both the Spring Seminar and the Stock Sense Class, so don't delay! SPRING SEMINAR We will be hosting our annual Spring Seminar on the 2nd of July. The topics to be covered include: Calving techniques and tips Downer cows and metabolic treatments Mastitis Lameness and Hoof trimming It is a great opportunity for new staff to be trained up, or old hands to get a refresher course from enthusiastic vets. Lunch and drinks will be provided. Notes will be available to keep as a resource. Cost: $50 (vet club members will be sponsored by the vet club.)

2 Due to the structure of the bovine placenta, the calf is born without protective antibodies and is totally dependent on the successful transfer of these vital antibodies via mum s colostrum. Multiple studies have shown that failure of this process markedly increases the risk of disease and death in calves. Between 40-45% of dairy calves in New Zealand have antibody levels below the satisfactory level and are susceptible to disease; most commonly calf scours, navel infections & joint ill. There are a number of factors that come into play when discussing why a calf has not received enough protection including, feeding poor quality colostrum, inadequate intake of colostrum, poor mothering or a delay in mothering instinct (cow being exhausted after a difficult or prolonged calving) & calves born to heifers. In NZ, the primary reason for failure of passive transfer is calves not sucking sufficient colostrum soon enough after birth. If we look at when a calf is born to when she is collected from the paddock the average length of time is 13.4 hrs and the average time it takes for that calf to start sucking is 4.5 hrs (range 1-19 hrs). We also know that a large number of calves are born during the cold of the night, these calves take longer to stand and therefore longer to suckle. From birth, the intestine s ability to absorb antibodies decreases so that by 9 hours of age the calf absorbs only half what it would have 8 hrs earlier. This ability continues to decline at a progressively greater rate until the gut closes at 24 hrs. It is no surprise then that 40% of NZ calves are receiving inadequate antibody protection. So what can we do to ensure our valuable replacements receive sufficient antibody protection? Remove the calf from the cow as soon as possible ensure two collections a day Use first milk colostrum in newborns Ensure each calf receives good quality colostrum - at least 2ltrs in 6 hours (10% of the calf s body weight). Use oesophageal feeder if necessary. Continue to feed 2L s colostrum twice daily for 5 days In addition to getting your calves off to a cracker start, early removal of the calf reduces the development of the mothercalf bond. The dam will spend less time searching for and protecting her calf and will focus on foraging. She will also have a lower risk of developing mastitis. Bonuses all round! SHEEP TO DO LIST Scan ewes and separate singles / multiples to feed accordingly Body condition score to feed up thinner ewes Trim feet of any lame sheep Pre-lambing drench Pre-lambing 5in1 vaccination to help protect lambs Have feeding bottles and colostrum ready for any orphans Look out for ewes with sleepy sickness (ketosis) or milk fever in late pregnancy as the foetal demand for energy and calcium increases dramatically have ketol and calcium ready. Inhibitory Substance Grades: Common Faults Josh Wheeler from QCONZ identified 8 main management areas that could be improved to reduce risk: Clearly identifying treated cows. Not cancelling out markings when withholding (WH) has finished can lead to milkers ignoring the markings. Also, colostrums cows need to be marked. Treatment Records - these are essential to be confident of WH, and availability to staff. Separation of Treated Cows - this includes not rowing up the treated cows behind the herd, and not milking non-treated cows within the treatment mob! Treatment administration especially treating cows in the milking herd, also incorrect WH times or treatment intervals. Medicine Storage have a locked cabinet, legible labels, within expiry date, DCT separate from milking cow tubes. Medicine Usage - correct dose, number of treatments, potential risk with multiple drug cocktail. Dry Cow Therapy Usage - delivery line disconnected, avoid DCT given to dry quarters, mark cows, maintain records, separate cows. Plant Cleaning Issues hot wash twice a day when colostrum / treated cows are being milked, check all clusters receiving wash. ORGANICS A recent comparison of a conventional and organic unit at Massey looked at mineral levels. Magnesium: It appeared that the organic herd had higher levels of magnesium and fewer cases of milk fever (2.7 vs 5.6 cases per 100 cows). Herbage magnesium was generally higher in the spring on the organic property, but not at other times of year. Copper: Herbage copper was higher on the organic unit for 8/10 years. This was probably due to plantain and chicory having twice the copper concentrations of perennial ryegrass or clover, although soil ph may play some part in copper-molybdenum interactions. Selenium: The organic unit did not have improved selenium levels, and required supplementation, as did the conventional farm. Cobalt: No difference between the two systems here. Iodine: Iodine teat spray should provide adequate levels, but in the drought year that cows were dried off early, an abnormal number of calves were born dead or weak, with enlarged thyroids. Stock iodine through the water prevented further problems. Having run Infovet for its first season, we are very happy with the options this system gives us: Better analysis of mastitis and mating data Easier / quicker paperwork for you, with prescriptions & inductions Bulk Cell Count Monitoring Pregnancy Testing results can be loaded onto a tablet and uploaded to Minda as we are scanning. Please phone the clinic to sign up to the future!

3 At Cambridge Vets we have a comprehensive range of what we think are the best products in the market place, at competitive prices, with professional advice to ensure you get through this season without a hitch. Calving gear - ropes, chains, handles Disinfectant, lube, gloves Pessaries, penicillin, oxytocin Metabolics - Calcium, Magnesium, Oral treatments Ketol, MPG, Starter Drench Rumensin Eprinex / Drench Bulk Magnesium, Molasses, Calcium, Salt Mastitis treatment, Intramammary & Injectable Teatspray and Udder Cream Hoof gear Calves Iodine spray, Electrolytes, tags, feeders Shed disinfectant, teats Be in to win...order/purchase any of the above deals/products before the end of July and go into the draw for a great escape prize. One entry for every $100 dollars spent.

4 Spring Product Deals! Kelvin has put together some early bird deals on these essential spring products. Purchase in July and be into win. See below for details. Magnesium - We stock or can have delivered on farm, magnesium drenching and dusting products including Agrimag, Nutrimag and Imperial. Give Kelvin a call for a great price, and good advice, on the best product for you and your budget. Bomac metabolic products -If you buy a box of 12, you will get one flexipack free! This includes the entire injectable range. The Bomac flexipack range is proven and reliable. Get those cows up and milking. We stock the professional range of these products which includes a dose of B12 to boost appetite. Our recommended treatment for down cows after calving is a bag of the appropriate calcium in the vein followed by an oral dose once the cow can swallow well and is alert. This will help to stop these cow relapsing and keep them eating. Remember that products containing dextrose like Calpromax/Calprophos should only be given in the vein. They are not absorbed well from under the skin. Oral calcium products: We highly recommend the use of oral calcium products instead of under the skin treatments. As long as the cow has a good swallow reflex. These products give much more calcium than putting a bag under the skin and it lasts much longer. We find it drastically reduces the number of milk fever cows that relapse. Most of these products have a burst of energy as well. We stock the following proven oral products. Calform Plus- Rapid acting calcium and a shot of energy that s easy to pour. The vets choice. Emulsi-Cal-In 400ml bottle or 4.8L. This is an excellent oral calcium drench to keep those milk fever cows on their feet after i/v treatment. Oral max - 650ml bottle and 10 Litre packs. Starter plus 200 litre Our proven cost effective post calving start up drench. Keep them on their feet and eating through the transition period. Its a cheaper price than last year. Drench deals -We recommend all heifers and cows are drenched at calving. There is good research work using Eprinex, in NZ, to show on average heifers get in- calf 13 days earlier and cows give an extra 8 kg of milk solids during lactation if treated as they calve. Eprinex - Buy 3 x 5 litre packs and get a 5 litre free of charge. Genesis litre - Still at a crazy price with 10% extra free. Be in to win...order/purchase any of the above deals/products before the end of July and go into the draw for a great escape prize. One entry for every $100 dollars spent.

5 KETO$I$ Ketosis is a profit-stealer & we now have a COW-SIDE TEST & service that will give you a quick assessment of ketosis in your herd. Ketosis is caused by a failure to cope with negative energy balance. This results in metabolic changes which mobilise body fat and muscle to supply additional energy. Negative energy balance is universal in dairy cows in early lactation and the degree of energy deficit coupled with other factors such as body condition and pre-calving nutrition will determine the severity of ketosis. Clinical Signs include loss of appetite, depression, sudden drop in milk production, a staring expression, an acetone smell on the breath, compulsive behaviour such as licking of rails and fences, chewing, bellowing, head pressing, followed by a staggery appearance and becoming a downer cow. Treatment: Increase available carbohydrate stores by better feeding, oral energy sources such as ketol, intravenous dextrose may be helpful. However, ketosis often remains sub-clinical; in New Zealand in 2009, a study of 58 herds determined a ketosis prevalence of 16.8% within 7-12 days of calving. In 2010 a study of 15 herds showed a ketosis prevalence of 25.7% one week post calving. But we can now provide a cow-side test and service that will give you a quick assessment of ketosis within your herd. This is best done with cows calved 7-14 days 1-3 weeks after start of calving. The cost of subclinical Ketosis can be up to $5700 per 100 cows for a high prevalence herd. The cost of a single case of sub-clinical ketosis is in the vicinity of $86 per case. Ketosis has multiple effects on health, production and reproduction and is considered a gateway disease for other problems including decreased six week in-calf rate, endometritis and milk production losses, which have been built into these cost estimates. Prevention and control strategies for ketosis will involve best practice management for feeding and reaching condition score targets in the lead up to, and immediately post calving. This is of course easier said than done, particularly when weather events can add an unknown dimension. Rumensin is a proven tool to assist in the prevention and control of ketosis, and is a logical choice from the start of calving. If practical, its use from 3 weeks pre-calving will deliver optimal results for both ketosis and milk production. A recent 857 cow study in 2012 using Rumensin in Waikato herds found an overall SCK incidence of 57% in untreated cows within 12 days of calving. Rumensin treatment reduced sub clinical ketosis incidence by 17.9% and also increased the proportion of cows with steady or increasing BCS after calving by 9%. Don t let subclinical ketosis be the silent robber on your farm; talk to us today for ways to assess and control this costly disease. The Downer Cow All of the above metabolic diseases may result in a downer cow, but so too can acute infectious diseases (mastitis, uterine infection, pneumonia, salmonella) or various injuries (leg fractures, dislocations, uterine rupture, post calving paralysis). If there is no dramatic improvement after treating an animal with metabolic disease urgent veterinary attention is warranted. All downer cows need to be provided with adequate feed and water, protection from harsh weather, and monitored for signs of improvement or deterioration. Downer cows may require more than 40 litres of water per day. Grass Staggers (Hypomagnesaemia) Grass staggers is caused by low blood magnesium levels. Unlike calcium, magnesium is not stored in the body and is required on a daily basis from the diet. This disease occurs most commonly in springtime due to increased requirements for magnesium from lactation and the fact that rapidly growing spring pasture is low in magnesium. Clinical Signs can occur in cows of any age, and is not confined to the period around calving, and may be seen any time during spring and autumn. Cows with grass staggers initially may show similar signs to cows with milk fever with a staggery, uncoordinated gait, often with a spasm of the eyelid muscles. This usually progresses to a cow becoming touchy or jumpy, and some cows may become aggressive and attempt to charge, followed by the animal going down, convulsing and dying if not treated. Many cows that reach the stage of having convulsions may die during or following treatment. Treatment: Restoring normal blood levels of magnesium with magnesium salts is required. Magnesium Sulphate is available in 25% solutions & can be given under the skin only, never put it in the vein as this will kill the animal. Warming the solution to body temperature may assist absorption. IV solutions containing a mixture of Calcium & magnesium (with Magnesium at a much lower concentration) can be given in the vein. Again, run the solution in slowly. Review your magnesium supplementation programme to be sure the cows are receiving enough. Milk Fever (Hypocalcaemia) Milk Fever is the most common cause of Downer Cows at calving time. It usually occurs in the 72 hours around calving and is most common in older cows and only occurs rarely in 1st and 2nd calvers. Milk Fever is caused by low calcium levels in the blood. Cows absorb calcium from their diet and store calcium in their bones. With the start of lactation at calving there is a sudden demand for calcium in the milk, the cow s blood levels of calcium drop and this triggers the release of parathyroid hormone to restore the blood levels of calcium. This is quite a normal occurrence, but only a few develop the clinical signs associated with milk fever. Signs may vary in severity but usually begin with muscle tremors, followed by a staggery gait then recumbency (sitting or lying down) and an inability to stand. Affected cows generally have their heads around to one side or sit with a kink in the neck. They appear depressed and respond poorly to stimuli. If untreated they may die. Treatment involves administration of calcium. Intravenous Treatment Use the jugular vein in the neck. This can be raised by placing pressure at the base of the neck and the vein usually becomes visible. Select a clean area of skin to insert the needle through and if possible disinfect the area first. Use a clean sterile needle! Blunt needles do not go into veins. Placing the needle into the vein at a slight angle should result in a flow of dark red blood from the needle. Attach the flexipack and slowly run the contents into the cow over at least 10 minutes. Running it in too fast may be fatal, so don t squeeze the bag! Subcutaneous treatment Again using a clean sterile needle, insert the needle under the skin along the neck or ribs on a clean area, and run contents of bottle or pack under skin. The area should be rubbed afterwards to spread out the solution to facilitate absorption. Solutions containing dextrose with calcium are only slowly absorbed from under the skin and should be avoided for this form of treatment. Oral treatments. When the cow is still standing or in a sitting position and able to swallow, this is often the treatment of choice as the solutions are rapidly absorbed and there is no mucking around with needles to find a vein. However care is required, and they should only be used on cows that are alert and able to swallow. Never force it down the throat of animals that are lying flat out.

6 MILK BACTERIOLOGY Milk cultures are a really useful tool to identify what wee bug is actually causing mastitis. This is a useful thing to do even if you are not having lots of difficult-to-cure cases. Knowing which bacteria are to blame can give you a handle on the underlying risk factors, and what farm issues may need looking at or fixing. Checking the antibiotic sensitivity will inform us for antibiotic choice, and warn us of any resistance issues. There has been some discussion amongst vets recently as to whether we are seeing different bugs to what we might expect at different times of the year, and if some previously effective drugs may be less effective nowadays. In addition, we can only know what is going on in your farm, and get a picture of the district in general, if milk samples are submitted. This will also help with the udder health and dry cow consultation later in the season. So I suggest: Taking milk samples of cases of mastitis, marking them with cow ID and date, and putting them in the freezer. Take spring and summer samples to get a full season picture. Teats wipes should be used to clean the teat, then the first few strips of milk discarded before squirting some into a clean pottle at a 45 angle (to avoid dirt dropping in). If you find you are seeing an outbreak of mastitis, or lots of difficult cases, you can drop them into the clinic. If your cell count is high, taking samples from high cell count cows can be informative. Remember, if you are having a mastitis or cell count problem, don t stress, just call us. We are Fonterra registered, and can help by doing a grade bust / mastitis investigation. Theileria Key Messages Over this past summer there was an increase in the numbers of cattle suffering anaemia (they tire easily, have poor appetite, and may have slower growth rates and reduced production) associated with the presence of a parasite that s transmitted by cattle ticks. This parasite is known as Theileria (Theileria orientalis). While we have had Theileria orientalis in New Zealand for some thirty years, the current situation appears to be related to a recently identified strain of Theileria called Ikeda. It has particularly affected stock in the upper half of the North Island and there has been one case in Canterbury. In some cases, animals show little signs of disease at all, but some herds have suffered clinical disease and animal deaths. Currently MPI has recorded 44 herds in Northland, Auckland, Waikato and latterly Canterbury affected, with about 70 cattle deaths. MPI is working closely with the cattle industries to gain a clearer picture of what s going on how widespread the issue is and how it can be managed. There is no cause for panic - the number of reported cases are relatively low and impacts from this condition are likely to reduce over time as cattle nationally build up immunity. This disease only affects cattle and is not a human health or food safety issue. Signs farmers could see in their cattle are: lethargy, poor growth, poor appetite, reduced milk production. Farmers noticing this kind of general illness should contact their vet. Stock most at risk are those that have not come into contact with Theileria previously (known as naive). There is no vaccine for Theileria currently available, and although no current treatments have yet proven 100% effective, treatments are being trialled on affected farms and there are some management practices farmers can apply. Specific advice includes: reporting suspect cases to vet; checking for ticks and treating regularly; resting affected animals; giving high quality feed and water to affected stock; minimising movement or yarding; and keeping an eye on newly introduced cattle to an infected area. Cambridge Vets have diagnosed several herd outbreaks, and recommend using tick control on farms where ticks are a known issue. It is best practice not to re-use needles, and to sterilize all taggers between animals (and other equipment that could transmit diseases). SMALL CALF GENE Following up farmer reports of calves born small, LIC have identified a recessive gene using genetic sequencing. The Small Calf Syndrome affects predominantly Holstein Friesian and a lesser number of crossbred animals. Incidence of the Syndrome has been assessed to be around one to two affected calves in the average 400 cow herd per year. The Small Calf Syndrome has probably been around for decades, but it will now be possible to breed it out of the national herd. Breeding companies can use this knowledge for screening to ensure future sires do not carry the gene, but several current high use bulls are carriers and will not be removed. Instead, they will be identified on DataMate to alert the AI technician if the cows is also a carrier. Because the gene is recessive, it is only expressed if both bull and cow are carriers, and 1 in 4 calves from such a mating would have small calf syndrome.