At a glance. Accurate identification and treatment of parasites can save producers time and money while enhancing production and profit.

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1 RESEARCH REPORT: Toni Nugent KONDININ GROUP At a glance Prices for cattle health products vary between suppliers so it pays to shop around for the best price. Seek advice and trial results before treating animals to ensure the most effective products are used. Producers can save money on their animal health bill by buying generic products and larger pack sizes. An integrated animal health programme allows producers to gain further benefits while decreasing costs. Integrated programmes wean animals onto clean pastures and use quarantine systems for new livestock. Use correct vaccination methods to reduce carcass damage, immunity failure or infection. Take time to understand the key disease risks for cattle to plan proactive animal health programmes. Are tiny microscopic organisms robbing you of valuable cattle returns? In this exclusive report, Kondinin Group researcher Toni Nugent goes undercover to give you the tools to spot a disease ambush and select cost-effective products to launch an attack. A national price survey has shown farmers could save at least $600 on their cattle health bills with minor changes to their management. The comprehensive Farming Ahead survey of cattle health products showed farmers could save by shopping around for the best price, buying large pack sizes and using generic products. Prices for cattle health products varied dramatically between suppliers. For example, Ivomec Eprinex Pour-on (20-litre pack) was $2150 $2522, a difference of $372. With many producers feeling the pinch of drought, shopping around will yield major savings. Price differences could be the result of pharmaceutical companies having preferred suppliers, selling to resellers for different prices and exclusivity agreements where certain manufacturers do not sell within specific networks. Generic products yield a saving One way cattle producers can save money is by using generic alternatives to patented products. When the difference between generic and brand products is calculated, producers can save almost $600 per calendar year on cattle health treatments. Generics have identical active ingredients as patented products but are produced by other manufacturers. These manufacturers are allowed to produce generics when the original patent expires. Accurate identification and treatment of parasites can save producers time and money while enhancing production and profit. Increased supply of the same product results in more competition which drives down prices. For example, Abamectin ranges from $0.68 per 100 kilograms to $1.50/100kg liveweight treated. Beware of special deals Most people are lured in by an attractive deal but buying decisions need to be based on more than the chance to gain a freebie. Toni Nugent 46 Farming Ahead December 2006 No

2 RESEARCH REPORT: There is little point buying a product to receive a freebie if the product is not needed. When it comes to buying a product, check the chosen formulation is registered. Table 1 (on page 50) and Table 5 (see pages 60 63) outline products from the 2006 Index of Veterinary Specialties (IVS) Annual showing those registered with the Australian Pesticides and Veterinary Medicines Authority. Time to manage diseases Producers who use integrated pest management (IPM) can decrease their reliance on drenches and vaccines by weaning onto clean pastures or using effective quarantine systems for new stock. In fact, producers who set up an IPM programme are better positioned to identify disease risks and minimise herd losses. Other tools such as pregnancy testing and management records will help identify fertility problems early, allowing quick action to slow disease spread across the property. Short joining times also help detect disease-induced fertility problems. Know the enemy Knowing the disease cause is vital to shape an effective response. Faecal egg counts and blood tests are useful to identify non-visible (subclinical) symptoms, allowing producers to take corrective action early to limit losses. For example, waiting for symptoms to appear before treating parasites could result in large losses. Typical symptoms include weight loss, reduced milk yields, poor conception, low calving and weaning rates and retarded post-weaning growth. These animals appear unwell but less-obvious subclinical diseases also could be insidiously wreaking havoc on herd production. Positive factors including lower worm burdens, low stress, effective nutrition, strong immune responses and genetics play a role in reducing the outward signs of an intestinal worm infestation. Spot the signs Failure to use faecal worm egg counts can allow disease to quietly eat away at production. Similarly, viral diseases such as pestivirus can go undetected for years without obvious signs. Disease symptoms include prolonged calving periods, deformed calves or poor doer s. If in doubt, seek advice from a veterinarian before implementing a management plan. Pesticide tolerance Chemical resistance is a major issue for cattle parasites but drench effectiveness can be prolonged with IPM. Save on health bills by buying generic products in bulk. The most severe resistance problems occur in cattle ticks and buffalo fly but options are available to preserve chemical effectiveness. IPM includes administering the correct dose, effective pasture management and applying chemical less frequently. Staving off parasites: Effective management of internal parasites incorporates several treatments that vary only slightly from yearto-year. Adopt programmes that allow additional treatments to prevent parasite numbers from reaching levels that cause economic impact at other times of the year. Fever in the blood: Cattle tick limit production and spread the blood disease tick fever. Check cattle for tick infestations and take appropriate control options such as chemical treatments and dips, tick vaccines and running tickresistant cattle. Fleur Muller Test before drenching: There is no point spending money on expensive animal health products if internal parasites are not limiting production. Carry out faecal egg counts to check the worm status of the herd. Kondinin Group NSW Department of Primary Industries Farming Ahead December 2006 No

3 RESEARCH REPORT: Disease risk: All animals are at risk of clostridial diseases including tetanus (inset) and blackleg (above) but younger animals are often at higher risk with operations such as marking creating an opportunity for clostridial invasion. Toni Nugent. Inset: Belinda Walker, NSW DPI Peter Windsor, University of Sydney Vaccines remove disease sting Vaccines are economical but incorrect application methods can produce carcass damage, immunity failure or even infection. For optimum disease protection, most cattle need two vaccinations at four and six weeks as well as an annual booster. The first dose prepares the animal for disease while the second stimulates a high antibody level to fight the disease. Animals are not protected from disease until they produce high antibody levels. Over time antibody levels decline unless animals are exposed to the disease through natural infection or as an annual booster vaccine. Vaccinations will be most cost effective if disease incidence is high, animal values are high, mortality or production losses are high and vaccine costs are low. Speak with a veterinarian to confirm disease suspicions before buying a vaccine. Clostridial diseases The clostridial bacteria are found in the soil, faeces and intestines of healthy animals. The bacteria produce diseases including tetanus, malignant oedema, enterotoxaemia (pulpy kidney), blackleg and black disease. But younger animals are more at risk due to their exposure to bacteria during operations such as marking and castration. Breeding females are at risk if they are injured during calving. All cattle are at risk of clostridial diseases, particularly calves. Treatments and dosage Use a 5-in-1 vaccine to treat calves from six weeks of age. Administer two doses 4 6 weeks apart, with the first dose 4 6 weeks before marking and subsequent annual boosters at marking. Give previously unvaccinated adult cattle two doses 4 6 weeks apart and a booster 12 months after the initial two shots for lifelong immunity against tetanus and blackleg. Annual boosters are necessary for immunity against black disease. Be aware that pulpy kidney immunity might only last 3 6 months, especially if feed changes occur. In this case, vaccinate valuable cattle and animals on grain, silage or pasture-rich diets twice yearly. Farming Ahead November December 2006 No

4 RESEARCH REPORT: Vaccinate correctly Step 2: If using a needle and syringe, draw vaccine into the syringe by pushing the needle through the rubber bung and inverting the vaccine pack (pictured left). Fill the syringe with the required dose and remove the needle from the bung. Step 1: Check the vaccine s use-by-date and whether it was stored appropriately. Ensure the syringe, draw-off tube and vaccine are sterile. A syringe is only sterile the first time it is used. The needle becomes contaminated when the first animal is treated. To maintain sterility, wipe the top of the vaccine pack with a 70 per cent methylated spirit solution and allow it to dry before the needle is pushed through the rubber bung. Swab the rubber bung again if a vaccine pack is reused at a later date. Pictured right: Vaccination guns are commonly used to administer vaccines. Set the gun to the correct dose level and draw vaccine into the gun. Ensure the tube is full and contains no air bubbles. To expel bubbles, hold the syringe upright and squeeze the plunger until all air is removed. TABLE 1 Prices for commonly used cattle vaccines (registered*) Active ingredient Trade name Dose and administration Pack size (ml) (ml/kg bodyweight) and price ($) Babesia bovis and Anaplasma centrale strains Bivalent tick fever vaccine, chilled 2mL subcutaneous or intramuscular injection. Babesia bovis, Babesia bigemina and Trivalent tick fever vaccine, chilled 2mL subcutaneous or intramuscular injection. Anaplasma centrale strains Campylobacter vaccine Vibrovax Subcutaneous injection. Females less than 18 months: 5mL, repeat four weeks later, then 2mL annually 4 6 weeks before mating. Bulls: 5mL, repeat four weeks later, then 5mL annually before mating. Clostridium antigens Ultravac 5-in-1 vaccine Initially 2mL subcutaneous injection into neck. Repeat four weeks later, then 2mL annual booster. Websters 5-in-1 vaccine for cattle and sheep 4mL subcutaneous injection into neck. Repeat 4 6 weeks later, then 4mL annual booster. Clostridium antigens and B12 Websters 5-in-1 vaccine with Vitamin B12 4mL subcutaneous injection into neck. Repeat 4 6 weeks later, then 4mL annual booster. Clostridium toxoids Websters low-volume 5-in-1 vaccine for Initially 2mL subcutaneous injection. cattle and sheep Repeat 4 6 weeks later, then 2mL annual booster. Tasvax 5-in-1 4mL subcutaneous injection into neck, then 4mL 2 3 weeks before calving. Clostridium toxoids and Leptospira cells Cattlevax LC 7-in-1 Initially 4mL subcutaneous injection into neck. Repeat 4 6 weeks later, then 4mL annual booster. Ultravac 7-in-1 vaccine Initially 2.5mL subcutaneous injection into neck. Repeat 4-6 weeks later, then 2.5mL annual booster. Websters Clepto-7 4mL subcutaneous injection into neck. Repeat 4 6 weeks later, then 4mL annual booster. L. hardjo and L.pomona vaccine Leptoshield vaccine Initially 2mL subcutaneous injection into neck. Repeat 4 6 weeks later, then 2mL annual booster. Websters Lepto HP vaccine 2mL subcutaneous injection. Repeat 4 6 weeks later, then 2mL annually one month before calving. Toxoids from both C and D Longrange Botulinum vaccine 2.5mL subcutaneous injection into neck. type Clostridium botulinum Annual booster. SingVac three-year single shot 2mL subcutaneous injection into neck. Bivalent Botulinum vaccine Booster dose 36 months after initial vaccination. Bovine pestivirus Pestigard 2mL subcutaneous injection. Annual booster 2 4 weeks before mating. * As registered with the National Registration Authority, 2006 IVS Annual, MIMS (other products since might have been registered). Check all dose rates, methods and withholding only. Prices were gathered from major product distributors in all Australian States and Territories. If more than one price was obtained, a range is provided. The cost per dose has Legend: A = Immunisation for cattle against pulpy kidney, blackleg, malignant oedema, black disease, tetanus and leptospirosis. B = Prevent botulism (carrion poisoning). ticks B. bovis and A. marginale. F = Immunisation for cattle against the ticks B.bovis, B. bigemina and A. marginale. G = Prevent Campylobacter fetus (vibriosis) infection. Source: Kondinin Group. 50 Farming Ahead December 2006 No

5 RESEARCH REPORT: Step 3: Administer vaccines subcutaneously (under the skin) and not into muscle. The direct jab method might be faster but it will increase injection site reactions. Subcutaneous vaccinations can be given anywhere on the body. High on the neck is ideal as it reduces damage to hides and meat. To inject a dose, grab a handful of clean skin with a free hand and position the needle at the base of the fold, taking care not to pass the needle through the skin fold. For valuable cattle, use a clean needle for each animal. Step 4: Never return vaccine into the pack. Keep a sterile needle in the bottle for drawing out vaccine or antibiotics and do not return the needle used on animals to the pack or bottle. Discard the syringe and drawoff tube after use. To maintain sterility, place tape over the top of the rubber bung and store vaccine in a refrigerator. Photos: Toni Nugent Pack size (ml) and price guide ($) Cost/dose ($) Withholding period Export Treats (days) slaughter (see Meat Milk interval legend) Nil Nil Not given E Nil Nil Not given F Nil Nil Not given G Nil Nil Not given D Nil Nil Not given D Nil Nil Not given D Nil Nil Not given D Not given Not given Not given D Nil Nil Not given A Nil Nil Not given A Nil Nil Not given A Nil Nil Not given C Nil Nil Not given C Nil Nil Not given B Nil Nil Not given B Nil Nil Not given H periods on manufacturer s instructions. Export slaughter intervals are based on correct re-treatment interval being applied. = Other pack sizes are available. Prices are a guide been calculated using an average of each guide price for each pack size. Prices include goods and services tax. C = Prevent leptospirosis. D = Immunisation for cattle against pulpy kidney, blackleg, malignant oedema, black disease and tetanus. E = Immunisation for cattle against the H = Immunisation against bovine pestivirus. Farming Ahead December 2006 No

6 RESEARCH : WORMS No excuse for internal parasites Producers can maintain high growth rates in their herds with careful management of internal parasites. Effective management will incorporate several treatments that vary only slightly from one year to the next. Cattle producers who control small brown stomach worm in a 100-cow herd can expect to be $3000 $8000 better off. By using several treatments producers can keep their cattle healthy and worm-free. Such treatments suppress parasite populations before they explode in response to favourable conditions (for example, early spring liver fluke and roundworms), minimise parasite burdens before cattle face major nutritional stress (for example, weaning), as well as help prepare animals for peak performance (for example, cows before calving or bulls leading into joining). These programmes allow additional treatments to be used to prevent parasite numbers from reaching financially devastating levels at other times of the year. Only use products targeted to the appropriate parasite and maintain flexibility to accommodate for seasonal changes and unusual weather. Parasite susceptibility Cattle vary in their susceptibility to parasites according to their age and sex. Age Young cattle are more susceptible to parasites than adults. As cattle age, their immune response strengthens. Health status An animal s health status will affect its ability to withstand a parasite attack. Cattle in poor condition will have a weak immune response. Poor nutrition during unfavourable conditions such as drought is the most common cause of stress, increasing the herd s susceptibility to parasites. Carefully monitor cattle on poor quality diets. Other common stressors include calving, lactation, weaning, droving, trucking, new environments, mixing cattle and cold weather. Naïve When cattle are moved to a new environment contaminated with parasites, they will be susceptible to infection until their immune system responds. A reaction can take several months and careful monitoring is needed. Breeds In most cases, breed does not have a major influence on an animal s susceptibility to parasites. The exception is cattle tick where Bos indicus breeds such as the Brahman are less susceptible than Bos taurus breeds like the Shorthorn. In this case, running Bos indicus breeds in tick-endemic areas can reduce the need for tick treatments. WORMS FIGURE 1 Life cycle of worms Worm burden: Worm larvae populations build up from spring to peak during late summer. Confirm suspicions with faecal egg counts. Drench cattle appropriately. When it comes to effective worm control, drench application and timing will have a larger impact than the brand used. Ostertagia and cooperia Small brown stomach worm (Ostertagia ostertagi) is the most prolific roundworm in temperate Australia. Cattle producers who control small brown stomach worm in a 100-cow herd can expect to be $3000 $8000 better off, depending on location and severity of the problem. While in the intestine, adult parasites mate and lay eggs, which are expelled in faeces. The eggs hatch in dung pats and swim onto pasture where they are picked up by grazing cattle (see Figure 1). Ostertagia have an inhibited stage, which enables them to form nodules in the stomach lining when pasture conditions are unsuitable. Larvae populations follow a regular pattern, building up from late spring and peaking during late summer. The nodules resume their development during autumn. Before selecting a drench, consider the herd s susceptibility to inhibited Ostertagia as efficacy at this stage varies. Cooperia are the main worm of 2 12-month-old cattle. These animals start to develop strong resistance to reinfection from six months of age and by 12 months only a small number of Cooperia become established. Source and illustration: Kondinin Group. Cooperia are important in early-weaned calves or where calves are heavily stocked. But in most situations Cooperia are not a serious threat. Cooperia is the limiting parasite for the macrocyclic lactone (ML) drenches. Adult cattle By two years of age most cattle have a strong immunity to worms and do not need drenching as adults. Only drench adults showing signs of parasites (those with scours) and bulls before and after mating. Where high worm populations are suspected, confirm with faecal egg counts. An animal s immunity will decrease when stressed such as during drought or at its first calving. Treat these rare outbreaks as they occur. A cost-effective drench programme will focus less on adults and more on cattle between weaning and two years of age. 52 Farming Ahead December 2006 No

7 WORMS : RESEARCH WORM TREATMENTS Strategic drenching and worm-free pastures can improve weight gains during the first spring after weaning by up to 60 kilograms per head. A sound understanding of the major drench classes will help producers make more informed buying decisions. Roundworm drenches Three drench classes are available for treating cattle roundworms the macrocyclic lactones (ML), benzimidazoles (BZ) and levamisole. Macrocyclic lactones MLs offer exceptional efficacy against internal parasites, particularly all stages of Ostertagia (see Table 2). MLs have superior persistence to other classes. Products such as doramectin and moxidectin have the longest persistence against Ostertagia. Persistence is important when cattle need to be returned to contaminated environments during autumn, winter or early spring. For example, spring-born calves weaned during autumn. MLs are best used at weaning. Persistence for autumn-born calves is less important as larval activity is lower in warm, dry summer conditions. When using MLs, consider generics such as Baymec Pour-on (for $1.18/100kg liveweight treated) compared with expensive brands that can cost up to $2.40/100kg when weaning autumnborn calves. Pour-ons versus injections Pour-on drenches have a higher dose of the active ingredient than injectibles but the price per dose is similar. Producers often prefer pour-ons for their ease of application, storage benefits and reduced potential for injection site lesions. For producers with clean and quiet cattle, use pour-ons but injectible drenches are a better alternative if animals are excessively dirty or conditions are dusty. Benzimidazole drenches The benzimidazole class is administered orally with the exception of the oxfendazole-based backline Alternate. The BZs offer high efficacy against adult and immature Ostertagia. Fendendazole and oxfendazole are more effective then albendazole against inhibited Ostertagia, with trial results suggesting they can remove 85% of inhibited larvae. Oral drenches usually cost about one-third less than ML drenches, which could be sufficient Peter Windsor, University of Sydney to cover the extra labour costs involved with oral drenching. Levamisole for Ostertagia Levamisole is available as a pour-on, oral and injectible product but its efficacy against inhibited Ostertagia larvae is low. Strategic drenching and worm-free pastures can improve weight gains after weaning by up to 60 kilograms per head. The product is highly effective against adult worms in calves less than one year old that have acquired worms during autumn and winter. For month-old cattle, levamisole is 50 80% effective. Levamisole can be cost effective in spring-born cattle (July October) weaned during autumn (March May) as they will not have ingested inhibited Ostertagia. Stomach worms: Controlling the small brown stomach worm (Ostertagia ostertagi) can increase net financial benefits in growing cattle by $3000 $8000 for a 100-cow herd, depending on location and the severity of the problem. The combination of strategic drenching and wormsafe pastures can improve weight gains in the first spring after weaning by up to 60kg per head. Bowel disease: Cooperiosis in young cattle can cause extensive disease of the bowel with hemorrhage, sometimes resulting in death. TABLE 2 Persistance of worm treatments Active ingredient Ostertagia Cooperia Abamectin Up to 14 days Doramectin Up to 35 days Up to 35 days Eprinomectin Up to 28 days Up to 28 days Ivermectin Up to 14 days Up to 28 days Moxidectin Up to 42 days Source: Kondinin Group. Peter Windsor, University of Sydney Farming Ahead December 2006 No

8 RESEARCH : PARASITES Beauty is not just skin deep External parasites tend to diminish the appearance of cattle leading to low prices at sale. This section details how to deal with costly external parasites that erode profits when herds come under attack. CATTLE LICE Lice treatments: Applying lice control treatments such as backline types are quick to use. Treat cattle when lice are causing stress or if there is excessive rub damage. In large numbers, sucking lice can cause anaemia. Lice populations are highest during winter and lowest in summer but they thrive when cattle are stressed, particularly when nutrition is poor. Lice irritate cattle causing them to rub, scratch and bite, attracting lower prices at sale. Diseased or nutritionally stressed cattle will develop more severe lice infestations than healthy animals. Two lice affect cattle: biting and sucking lice. The cattle-biting louse (Bovicola bovis) feeds on skin debris and causes severe irritation. Sucking lice such as the short-nosed cattle louse (Haematopinus eurysternus) and the long-nosed cattle louse (Linognathus vituli) pierce the skin and suck blood. In large numbers, sucking lice can cause anaemia. Lice populations are highest during winter and lowest in summer. Cooler skin temperatures are associated with heavier lice infestations with dense winter coats and cooler weather favouring lice survival. Lice thrive when cattle are stressed, particularly when nutrition is poor. Improved feed conditions and warm temperatures favour low lice numbers. Controlling lice Several insecticides are registered to control cattle lice (see Table 3). These include organophosphates, synthetic pyrethrins, insect growth regulators and MLs. If cattle appear to be in a poor condition, investigate if lice are the cause. If lice are not the cause treatment is unnecessary. Treatment is warranted when lice cause stress or if there is excessive rub damage before a sale. Application times Many insecticides do not effectively kill louse eggs, requiring treatment 2 3 weeks later. This interval is critical for effective TABLE 3 Comparison of chemical groups for lice treatment control as it allows the eggs to hatch but not mature into adults. Chemical timing and frequency depend on individual circumstances but in most cases treatment during late-autumn or early-winter will provide adequate lice control. Several lice products are available with little difference in their efficacy so allow price to influence the buying decision. Backline lice treatments are quick to apply but some can adversely affect dung beetles. Only use ML drenches for lice if internal parasites are present, otherwise they are unnecessary. Using narrow spectrum products such as synthetic pyrethrins will reduce selection for resistance. Treatment group Pros Cons Organophosphates Low price Toxicity to operator and cattle (bendiocarb, famphur, phosmet fenthion, diazinon) Synthetic pyrethrins Low price Toxicity to operator and cattle (deltamethrin, flumethrin, zeta-cypermethrin) Environmental impact Insect growth regulators Environmentally friendly Operator safety (diflubenzuron, fluazuron) Macrocyclic lactones Activity against a range of internal Expensive for lice control alone (abamectin, doramectin, ivermectin, and external parasites eprinomectin, moxidectin) Source: Kondinin Group. Pamela Lawson 54 Farming Ahead December 2006 No

9 PARASITES : RESEARCH BUFFALO FLY Queensland cattle producers rate buffalo fly as the most important animal health issue affecting their profitability. Surveys show producers spend $4 $6 million a year on chemicals to control buffalo fly at an industry-wide cost of $20 $30 million. The buffalo fly is a small biting insect found in northern Western Australia, Northern Territory, Queensland and north-eastern NSW. Untreated infestations can cost producers up to $30 per head in lost production. One Queensland study showed a steer protected from buffalo fly could gain an extra 14% in bodyweight over 13 months. Another study showed cattle protected from flies gained an extra 33 kilograms over 21 weeks. Unprotected animals have lower milk production and cattle develop sores in the inner corners of their eyes. Some cattle are allergic (hypersensitive) to buffalo flies and are irritated by as few as four or five insects. Adult flies live for 2 3 weeks, with peak activity from late-january to May. Bulls, old animals and dark-coated cattle usually attract the heaviest burdens. Treatment options Cull hypersensitive cattle from the herd. Treat the herd when infestations are more than 200 flies per animal. NSW Department of Primary Industries Buffalo flies have developed resistance to some insecticides so use IPM. Use chemicals strategically with non-chemical methods to reduce the risk of meat and milk residues. Non-chemical treatments involve culling hypersensitive cattle, buffalo fly traps and increasing dung beetle numbers. Chemical treatments include ear tags that slowly release organophosphate (OP) or synthetic pyrethroid (SP) insecticides, OP or SP backline or full body sprays, OP, SP and ML pour-ons, back rubbers and dust bags. Buffalo fly trap: If left untreated, buffalo fly infestations can cost producers up to $30 per head in lost production. Buffalo flies have developed resistance to some insecticides so use nonchemical control options such as buffalo fly traps as part of the management programme. BOVINE EPHEMERAL FEVER Three-day sickness or bovine ephemeral fever (BEF) is a viral disease spread by biting insects such as midges and mosquitoes. BEF usually occurs in north-eastern Australia, including the NT, and follows a pattern of sporadic cases for 1 2 years and then moves south. Outbreaks usually occur during January-April with most cases in March and some from December to early June. Cases during winter and spring are rare. Symptoms and treatment BEF symptoms include a sudden onset of fever, loss of appetite, excess watery discharge from the mouth, nose and eyes, lameness and stiffness. Cattle are usually sick for a few days followed by a rapid and complete recovery. Dairy cows show a sudden and severe reduction in milk production (at least 50%) and pregnant cows can abort. Bulls and fat, lactating cows are at most risk with animals rapidly losing condition and slowly regaining bodyweight. Some bulls can become infertile for 3 6 months due to high fever. Permanent infertility is uncommon but does occur. Treatment is only necessary in bulls and highmilk producing cows during early- to peakproduction. Give cattle a calcium injection to help them stand and anti-inflammatory drugs for recumbent animals. Most BEF-affected animals are resistant to repeat infection but older cattle might lose immunity after a few years. Vaccinate against BEF using one of two vaccines live and inactivated. Toni Nugent Live vaccine requires a veterinary prescription. This freeze-dried treatment gives at least 12 months protection after two doses. The inexpensive inactivated vaccine is refrigerated and easy to use but only provides about six months protection. Protection is only provided when two doses are given four weeks apart. Cattle can be vaccinated from six months of age and given an annual booster vaccination for ongoing protection. For dairy herds, vaccination will protect against milk production losses. Vaccination is necessary in areas prone to BEF outbreaks or in commercial herds during high-risk periods coinciding with heavily pregnant animals or steers close to finished market weight. Watch for discharge: Bovine ephemeral fever or three-day sickness is a viral disease spread by biting insects. Outbreaks occur from January April, with affected animals sick for a few days followed by rapid and complete recovery. Symptoms include excess watery discharge from the mouth, nose and eyes, lameness and stiffness, sudden onset of fever and loss of appetite. Farming Ahead December 2006 No

10 RESEARCH : PARASITES CATTLE TICK High cost: Cattle tick costs the Australian cattle industry more than $150 million each year. Cattle ticks affect about one-third of Australian cattle resulting in rapid weight loss, lack of energy, anaemia and reduced milk production. Plunge dips are one chemical option for controlling cattle tick. Ticks (Boophilus microplus) cost the Australian cattle industry more than $150 million a year. They affect about one-third of Australian cattle and severely limit production. The cattle tick also spreads the blood disease tick fever. In Queensland alone, one in 20 animals at risk of tick fever will die during an outbreak. Surviving cattle lose condition, have reduced milk production and are at risk of abortion or loss of bull fertility for up to one breeding season. Tropical (Bos indicus) cattle and their crosses develop better resistance to ticks than British breed Bos taurus and European cattle. As a rule of thumb, the more Bos indicus within a breed or cross, the better the tick resistance. Cattle ticks are most active from late-spring to mid-winter. Adult females feed on cattle for about one week and drop into pasture to lay eggs. If temperatures are more than 15 degrees Celsius a female tick will produce eggs. Larvae or seed ticks climb grasses and wait for a passing host. TABLE 4 Returns for tick fever vaccination* Parasite Bos indicus 50% Bos taurus Bos indicus Anaplasma marginale $22 $40 $53 Babesia bovis $1 $5 $55 Babesia bigemina $1 $2 $44 * Estimated returns for tick fever vaccination in weaners. Source: Meat and Livestock Australia. NSW DPI Larvae can survive in pasture for up to two months during summer or 6 7 months during winter. Seed ticks pierce the skin and suck white blood cells. From day 4 13 they shed their skin and nymphs emerge, which undergo another moult to become adults about two weeks after the seed tick has attached to the host. Symptoms of tick infestation Heavy tick infestations result in anaemia, licking and rubbing at bite sites (tick worry), tick sores, ulceration, lack of energy, rapid weight loss and death. One female adult tick feeding on a cow can reduce milk yield by nine millilitres and weight gain by 0.6 grams per day. To eradicate ticks, spell pastures, use chemical treatments and run tick-resistant cattle. Some chemicals will also treat other pests such as buffalo fly and lice. Two vaccines are available to protect against all three tick fevers or just Babesia bovis and Anaplasma marginale. See Table 4 for returns on vaccinations and Table 1 on page 50 for detailed vaccine information. This space is deliberately blank 56 Farming Ahead December 2006 No

11 INFERTILITY : RESEARCH Healthy lifestyle boosts fertility Cattle producers can reward themselves with excellent conception rates and high calf numbers with careful attention to herd fertility. Managing herd fertility and careful attention to disease prevention will pay off in more, healthier calves. Cattle infertility can be expressed in several ways. Some cases cause early embryonic death followed by recovery and successful conception. This is reflected in prolonged calving periods if bulls remain with cows. Other cases lead to abortion, resulting in empty cows. Abortions can be sporadic and small in number or appear as sudden abortion storms. Some pathogens produce weak calves or calves that are born healthy but fail to thrive before or after weaning. Occasionally, deformed calves can appear due to viral exposure of the dam during pregnancy. Some cases result in poor calving rates with no evidence of sick bulls, cows or calves. Common and preventable causes of infertility include intestinal parasites, pestivirus, Neospora, vibriosis and leptospirosis. A veterinarian will diagnose the disease and help develop a treatment programme. Treating pestivirus in an infected herd can lift annual production by 5 10%. PESTIVIRUS Bovine pestivirus affects all types of cattle, with about 70 per cent of Australian beef herds infected. Production losses of 25 40% have been recorded due to reduced reproductive performance, death and ill-thrift. Left untreated, pestivirus commonly reduces annual production by 5 10%. Pestivirus symptoms The complex disease pestivirus can cause a variety of diseases in cattle with some developing immediately after exposure to the virus and others later in life. Symptoms of pestivirus include ill-thrift, diarrhoea and infertility. Depending on the virus and pregnancy stage, cows can fail to conceive, abort, reabsorb an early pregnancy and return to service, produce a stillborn or deformed calf or give birth to a calf that carries the pestivirus. Carriers appear normal or as poor doers. While poor doers usually die before two years of age, they harbour the virus, enabling it to persist on a property. Many carriers are left with the herd and considered one-offs, while other herds might experience infertility. Failure to investigate the disease will lead to inappropriate drenching. But a simple faecal worm count will help avoid costly mistakes. If parasites are ruled out, blood tests might reveal that one miserable weaner could be the source of infection in four-year-old cows on the other side of the property. In older animals pestivirus causes lethargy due to fever, respiratory disease and lesions on the feet and muzzle similar to the symptoms of foot and mouth disease. Sarah Robson, NSW DPI Managing pestivirus Herds with pestivirus need careful management to stop the disease from spreading. High protection against the disease requires an ongoing vaccination programme. Before vaccinating, discuss the programme with a veterinarian. Initially, the entire herd will need treatment with two further vaccinations 4 6 weeks apart according to label directions. Complete the treatment at least two weeks before joining. In intensive systems, treat animals 2 4 weeks before contact with other cattle. Worm counts vital: Pestivirus carriers within a herd can appear as poor doers and are often considered one-offs and left to run with the herd. Sickly animals are often drenched with inappropriate products at inopportune times. Simple faecal worm counts can help avoid costly mistakes. If parasites are ruled out, blood tests might reveal that one miserable weaner could be the source of infection in older cows on the other side of the property. Farming Ahead December 2006 No

12 RESEARCH : INFERTILITY NEOSPORA CANINUM Pop-eyed appearance: Neospora is a major cause of abortion in cattle and is estimated to cost the Australian dairy and beef industries more than $110 million annually. Adult cows show no clinical signs of illness and most have normal pregnancies. Infected calves are born with abnormalities including lack of co-ordination, underweight and unable to stand, decreased reflexes and sensory perception and a pop-eyed appearance. The disease Neospora caninum is a major cause of abortion. The parasite is a microscopic protozoan estimated to cost the Australian dairy and beef industries about $110 million annually. In areas such as the New South Wales north coast the parasite is responsible for more than 30 per cent of cattle abortions. A survey of central Queensland beef producers showed that in 1400 beef cattle, more than 15% of animals were infected with the parasite. Neospora caninum infections are not frequently diagnosed inland but this could be because aborted foetuses are less likely to be noticed in pastoral areas. Disease spread and diagnosis Cows act as in intermediate host of Neospora caninum and are usually infected by eating parasite oocytes (eggs) passed by a dog. Infection also passes from a cow to her foetus via the placenta, which is the main infection source in herds. When infected, adults show no signs of illness and most have normal pregnancies. Abortion due to Neospora caninum usually occurs when cows are 4 7 months pregnant but it can happen from three months onward. Abortion does not always occur when the embryo dies. Mummified or partly digested foetuses can be expelled. Sometimes infected calves are born with abnormalities including lack of co-ordination, flexed or hyper-extended limbs, poor birthweights LEPTOSPIROSIS The bacterial infection Leptospirosis is caused by Lepstospira hardjo and L. Pomona that colonises in the kidney and genital tract. When bacteria are shed in urine and from the genital tract, the disease can spread to humans and other animals. In young calves, symptoms include infertility, abortion, fever, jaundice and red water but infected adult cattle might not show any signs of illness. Belinda Walker, NSW DPI Peter Windsor, University of Sydney and an inability to stand, decreased reflexes and sensory perception and popped eyes. Sometimes an abortion storm occurs where many cows abort within a short time. These storms usually result when the herd is exposed to something that reduces immunity in a previously infected herd, resulting in parasite re-activation. This could include exposure to toxins in mouldy feed. Laboratory tests of aborted foetuses are necessary for diagnosis. The brain and heart are the best specimens for diagnosis as they show distinctive changes under the microscope. Blood samples or foetal fluids also can be tested for antibodies. Not much is known about Neospora caninum, making control difficult. Where possible, prevent dogs from defecating in cattle feed, scavenging aborted foetuses and eating afterbirth. Aborted foetuses: Leptospirosis bacteria are shed in urine and from the genital tract of infected animals into the surrounding environment. Leptospirosis can result in infertility or increased returns to service and aborted foetuses but infected adult cattle may not show any signs of illness. When to vaccinate The risk of infection varies according to location. Bacteria spread in water and are usually found in highrainfall areas. Beef herds in areas with less then 550 millimetres of rainfall are unlikely to report outbreaks more than 1.2% of the time. So, for example, with a live calf valued at $200, calf deaths need to be more than 1.2% for vaccination to be worthwhile. The disease can spread to people who come in contact with the urine of infected animals. For most beef producers, the risks are low. But for producers in close contact with their livestock or those medically susceptible such as the aged or young children, the risk might justify the negative returns from vaccination. Which vaccine? A treatment is available as a dual-acting vaccine that protects against L.hardjo and L.pomona or as a mixture in combination with 7-in-1. A 7-in-1 vaccine is convenient to use, conferring similar immunity as the single leptospirosis vaccine. The combined vaccine saves time and labour as only one injection is necessary, causing less skin irritation to the animal and only one injection site. Seek veterinary advice to confirm whether to vaccinate cattle with a single leptospirosis treatment or 7-in-1. In high-risk areas, vaccinate all calves with 7-in-1 at marking and again at the next yarding. Follow with an annual booster for all livestock. Always check label directions as the optimal age for first vaccination varies between products. To reduce costs in low-risk areas, give steers a 5-in-1 shot and breeders a 7-in-1 booster annually. Vaccinate all breeding stock one year later with 7-in-1. All other cattle can be given an annual 5-in-1 booster. 58 Farming Ahead December 2006 No

13 INFERTILITY : RESEARCH VIBROSIS The disease bovine vibriosis or Bovine Venereal Campylobacteriosis (BVC) is caused by Campylobacter fetus bacteria. BVC can reduce gross margins up to 65 per cent in the first year. When established in herds, gross margins are usually 35% less than non-infected herds. Infected animals show no symptoms but herd conception drops by up to 40%. As immunity develops, calving rates increase to about 65 75% but re-infection often occurs as immunity wanes about one year after initial infection. Vibriosis could be suspected if bulls are working and cows are cycling but no calves are produced. This is obvious if many cows return to cycling as a result of early embryonic losses. If the joining period is sufficient, an infected cow might develop immunity and eventually become pregnant. Use laboratory tests to confirm the disease in cows but the results for bulls are not as reliable. BOVINE RESPIRATORY DISEASE BRD or Bovine Respiratory is common in feedlots and affects the airways. Because animals from different herds come together in close proximity under stressful conditions, the spread of viral and bacterial diseases can affect returns. The most common disease agents are pestivirus (Bovine Viral Diarrhoea Virus), Bovine Herpes Virus (Infectious Rhinotracheitis Virus) and Mannheirnia haemolytica. These three viruses are often combined and referred to as BRD, estimated to cause per cent of all feedlot illnesses at an annual cost of $60 million. Symptoms of BRD BRD usually occurs within the first 3 4 weeks of feedlot entry. Symptoms include low interest in surroundings and an unwillingness to stand and move. Coughing can be present and there is usually a discharge from the nose and eyes. The breathing rate is initially increased with rapid, shallow movements. Failure to treat cattle early can lead to death. Vaccine teatment An appropriate vaccine programme will prevent all three diseases. Pestigard (Pfizer) protects against Bovine Viral Diarrhoea Virus; Rhinogard (Q-Vax) is an intra-nasal vaccine against infectious Bovine Rhinotracheitis and Bovilis MH (Intervet Australia) protects against Mannheirnia haemolytica, the major component of BRD. Several Australian feedlots require cattle to be vaccinated before entry. Robert Bridle Belinda Walker, NSW DPI Disease spread is via bulls Bulls spread vibriosis to susceptible cows through sexual contact. Immunity in bulls is not easily developed and a bull can be infected for a long time without obvious signs. Controlling vibriosis Vaccination is the best way to control vibriosis. Vaccinate all bulls at joining even in herds where vibriosis has not been identified. Provide two injections 4 6 weeks apart during the first year and a single booster in subsequent years. Vaccinate four weeks before joining. To manage BRD, Elders has developed the Feeder Guard programme, a third-party (AUS- MEAT Limited)-audited membership commercially available to producers supplying feedlots. The programme enables suppliers to identify cattle treated according to prescribed protocols. Feedlots can easily identify and pay premiums (minimum of $6 per head) for cattle supplied under the programme. ACKNOWLEDGEMENTS Lou Beck, Wagga Wagga Veterinary Hospital, New South Wales; Greg Duncan, Pfizer Animal Health; CRT; Landmark; Elders; Nick Austin, Adelong, NSW; Robert Bridle, Dalby, Queensland; David Buckley, Charles Sturt University; Sarah Robson, Belinda Walker and Phil Bevan, NSW Department of Primary Industries; Peter Windsor, University of Sydney; and Meat and Livestock Australia. Testing is essential: Vibriosis is one of the most important venereal diseases in Australian cattle, reducing gross margins by up to 65 per cent in the first year of infection. Laboratory tests of semen from bulls will confirm a herd s disease status. Feedlot disease: BRD or Bovine Respiratory Disease affects the airways and is a major problem in cattle feedlots. BRD results in per cent of all feedlot illnesses, costing the Australian cattle industry about $60 million annually. BRD commonly occurs during the first 3 4 weeks of feedlot entry. Farming Ahead December 2006 No

14 RESEARCH REPORT: TABLE 5 Prices for commonly used cattle health products (registered*) Trade name Dose and administration Pack size (ml) and price guide ($) and active ingredient (ml/kg bodyweight) 100mL 200mL 250mL 500mL 1L 2L 2.2L 2.5L 5L Abamectin Genesis injection 1mL/50kg, subcutaneous injection into neck. 190 Paramectin injection 1mL/50kg bodyweight, subcutaneous injection into neck. 170 Paramectin pour-on 1mL/10kg bodyweight, with applicator Virbamec antiparasitic 1mL/50kg plus 1mL for every 50kg more than 650kg, 366 injection subcutaneous into neck. Virbamec pour-on 1mL/10kg bodyweight, cattle more than 650kg need an endectocide additional 5mL/50kg over 650kg. Abamectin and triclabendazole Genesis Ultra pour-on 1mL/10kg bodyweight, with applicator Albendazole Strategik mini-dose 3mL/45kg orally (worms), 4mL/45kg orally (worms, fluke) 183 Valbazen broad spectrum 3mL/45kg orally for worms, mini-dose 4mL/45kg orally for worms and fluke. Amitraz Amitik WP Mix 500g/1000L water, refer to instructions. 500g water-soluble sachets 58 Amitraz and liquid hydrocarbon Taktic EC 400mL/200L water, spray thoroughly as directed Amitraz EC cattle and 400mL/200L water, spray thoroughly as directed pig spray Amitraz and hydrated lime Taktic WP Dips: 500g+10kg stabiliser/1000l water. 500g water-soluble sachets 58 Spray races: 500g/1000L water. Chlofenvinphos liquid hydrocarbons Supona Buffalo Fly insecticide Refer to product label Cypermethrin Cypafly Buffalo Fly Spray Mix 40mL concentrate/10l water Cypermethrin and chlorfenvinphos Barracide S cattle dip 1 in 250 parts water , 4 and spray Deltamethrin Arrest Easy-Dose Up to 100kg = 5mL, kg = 10mL, kg = 15mL, kg = 20mL, kg = 25mL, kg = 30mL, more than 650kg 5mL/100kg bodyweight. Coopers Easy-Dose 5mL/100kg bodyweight, backliner gun Deltamethrin and ethion Tixafly Plunge dip: 1L/500L water, then top up as indicated. Hand 485 spraying: 400mL/200L water, spray at 10L dilution/beast. Deltamethrin-hydrocarbon liquid Coopafly Flies: 2mL/100kg bodyweight. Lice: 4mL/100kg/bodyweight 750 with backliner gun. Diazinon Di-Jet Buffalo fly: back rubber at rate of 500mL/10L oil Lice: hand spray at 250mL/100L water using 5 10L/head. Nucidol 200 EC Lice: 250mL/100L water, spray thoroughly as directed; 24 Buffalo fly: 400mL/100L water, spray thoroughly as directed, back rubber and rubbing post: 500mL/10L oil, repeat after 14 days. Y-Tex Optimiser Apply tag to each ear (two tags/animal). Tags: 20, 100 and Diazinon and chlorpyrifos Y-Tex Warrior Apply a tag to each ear. Controls buffalo fly for 12 weeks. Tags: 20 = $68, 100 = $298, 500 = $1360 Doramectin Dectomax injectible 1mL/50kg bodyweight, subcutaneous 278 Dectomax pour-on 1mL/10kg bodyweight, with applicator Eprinomectin Ivomec Eprinex pour-on 1mL/10kg bodyweight, with applicator Fenbendazole Fencare 100 3mL/40kg bodyweight, oral drench. 170 Panacur 25 15mL/50kg bodyweight, oral drench Panacur mL/50kg bodyweight, oral drench Fenbenazole plus a Mineralised Fencare 15mL/50kg bodyweight, oral drench. * Registered with the National Registration Authority, 2006 IVS Annual, MIMS (other products since might have been registered). Check all dose rates, methods and withholding periods on resale merchants. The cost per 100kg bodyweight was calculated using an average price for each pack size but if there are no prices given, the cost could not be calculated as there is no 30 days of calving. 1b = Or within 42 days of calving. 1c = Or within 60 days of calving. 1d = Or after the first mating. 1e = Or within 28 days of calving. a = Fenbenazole plus cobalt, Legend: A = Susceptible early immature, immature and mature liver fluke. B = Susceptible immature and mature roundworms, lungworms and tapeworms. C = Adult liver fluke only. Susceptible immature and mature other worm species inlcuding barber s pole worm, hookworm and nodule worm. H = Sucking lice. I = Biting lice. J = Cattle ticks. K = Used to treat 60 Farming Ahead December 2006 No