Blowflies have just started buzzing around as the weather tries to warm up and we've still got lots of moisture around. The production impacts, welfare impacts and efforts needed make this is big problem. We’d be preaching to the converted to say that this is a disease worth preventing. So how is it done?

• The easiest way to manage the issue is a long-term plan to breed a flystrike-resistant flock. This is achieved by selecting rams with low wrinkle and low dag breeding values. It is surprising how quickly gains can be made towards a hardy flock of flystrike-resilient sheep.
  
  
• Short wool dries fast. Therefore the timing of shearing and crutching sheep is important. You are able to create your own risk assessment using the flystrike decision support tool which sits on the Flyboss website. This allows you to assess the risk of flystrike when moving shearing, crutching and chemical treatments to different times of year. The risk is based on local historical climatic data.
  
  
• The application of long-acting chemicals is effective either before or during peak risk periods. Clearly, this needs a plan, as most chemicals have withholding periods.
  
  
• Breech modification is an effective way of reducing flystrike risk. Some tips for this include:
  
  
  • Tail dock lengths should just reach the tip of the vulva in ewe lambs- long enough to swish some flies and reduce prolapse risk
  • Equipment must be kept sharp and frequently disinfected.
  • Mulesing is effective, especially in flocks with poor flystrike resistance. When done, TriSolfen should be applied immediately post-procedure. If you’re still mulesing, you should be aiming to breed hardy, flystrike-resistant sheep that don’t require mulesing.
  • Prompt treatment of any struck sheep is important. The best guides on treatment, including video, can be found here.

With the large prices being paid for trade cattle at present, it’s important to induct them well onto your property to both prevent them developing disease and to minimise the chance of them spreading a new disease into your herd. Here are some important points:

PRIOR | Pre-arrival/purchase

• Obtain a Cattle Health Statement from the vendor, check treatment history and assess risk of key infectious diseases.
• Check yards and new paddocks, assess water quality and remove or limit access to toxic plants.

FIRST 24 HOURS | Unloading

• Provide ad lib access to good quality water (<5000ppm) and good-quality hay.
• Count animals onto the farm and check for transport injuries. Seek help if needed.

24-48 HOURS | Animal health treatments

• Vaccinate with Ultravac 7-in-1. Don’t forget to re-vaccinate in four weeks if the vaccination history is nil or unknown.
• Vaccinate with Bovi-Shield MH-One and an IBR vaccination to protect against respiratory disease - speak with us about options.
• Quarantine drench with a combination drench. Dectomax V is a good choice.
• Check liver fluke status of farm of origin and decide if a flukicide treatment is necessary.

DAY 2-28 | Isolation/quarantine period

• Keep cattle in isolation (either in containment yards or accessible paddocks).
• Observe cattle for key health conditions - pneumonia, pink eye, lameness, scours.

DAY >28 | Turning out

• Ensure cattle are full and watered before walking to the destination paddock to minimise pulpy kidney risk and ingestion of toxic plants.
• If boxing mobs, beware this is a stressful event for cattle, and a time that new diseases transfer.
• Consider pestivirus status. Boxing pregnant mobs of cattle can lead to a pestivirus outbreak.

Vaccination of breeding animals is critical to reduce the risk of pestivirus outbreaks.

Foot abscess often occurs when horses experience varying ground conditions between dry and soft or muddy. There is evidence that horses that are unshod are more prone to this condition particularly near the white line when there are cracks in the wall of the hoof.

Horses with foot abscesses can be mildly lame initially but this may progress to non-weight bearing as the abscess grows. The abscess can sometimes self-drain and then reseal and grow again producing lameness that varies in severity. 

Diagnosis
A hoof affected by this condition will often be hot and sensitive to pressure. The leg above the hoof may be swollen, particularly if the abscess has started to drain. The drainage point is often along the edge of the hoof (coronary band).

There may be a dark spot or a crack visible near the white line on the bottom of the hoof indicating where the abscess has drained. This tract can be explored by our veterinary team with a hoof knife and will run towards the centre of the hoof.

X-rays can be helpful too, especially if there is a foreign object in the hoof, or  in rare cases when the bacteria produce gas. Horses with hoof abscess may or may not respond to nerve blocks.

Treatment
You could probably write a whole textbook on foot abscess treatment as there are many levels of severity and complications.

In straightforward cases, we will make a narrow hole to establish drainage of the abscess and also to allow a poultice to be applied to help the pus drain effectively. A narrow hole will help your horse start using the hoof quicker after the infection has been treated.

Poultices are relatively easy to use these days, rather than the old, large wads of cotton wool with venus turps and thick bandages to keep it in place. These days poulticing for a week is much easier, as long as the feet stay dry.

When re-examining at the end of the week, the horse should no longer be lame. The whole process may need to be repeated if the hole has sealed up too soon and infection re-establishes. When this treatment is successful, the whole can be plugged with betadine-soaked cotton wool until a farrier can shoe the horse and cover the hole with a breathable packing.

Pestivirus is a highly contagious virus that is spread throughout the dairy and beef herds of Australia. It is estimated that 60-70% of beef herds have this disease actively circulating. When pregnant cattle are infected, there can be major problems.

The impact of infection of pregnant cows depends on the stage of pregnancy when infected. Infection during the first six months of pregnancy can result in loss of the developing calf. If the cow is pregnant during the first trimester when infected, she can subsequently abort, often later in pregnancy or deliver a stillborn calf. If the cow is between one-and-four months pregnant when infected, a persistently infected calf can be born (PI or shedder) although abortions and stillbirths can also occur. Between four-and-six months of pregnancy, the calf may be born persistently infected but is more commonly born with deformities of the eyes and brain including small eyes and dome heads (dummy calves).

A study investigated reproductive losses in cattle infected with pestivirus around artificial insemination. In this study, heifers infected with pestivirus around the time of artificial insemination had a 45% reduction in conception rates.

Source: A field investigation of the effects of bovine viral diarrhoea virus infection around the time of insemination on the reproductive performance of cattle. Theriogenology 39:443-449

The cash cow project in Australia reported a 23% reduction in cows becoming pregnant within four months of calving and an increase of 9% in calf wastage (losses from pregnancy testing to weaning) in herds with active infection.

This is one of the most important reproductive diseases in Australia and needs to be controlled. There is a vaccine available to control pestivirus. It is called Pestigard and it provides good protection for your breeding stock. Other biosecurity plans also help reduce risks. Please speak with us about implementing a program.

The most common cause of blindness in horses is an inflammation of the eye called uveitis. This condition can be acute or it can recur, often frequently in a condition sometimes called “moon blindness”. It is a group of diseases characterised by inflammation of the inner tissues of the eye. This inflammation is often an overreaction of the immune system to some injury or infection.

Cause(s)
Acute uveitis can be triggered by a wide range of infectious incursions, including bacterial (such as leptospirosis), parainfluenza or parasitic (such as toxoplasmosis). A range of other conditions including trauma (like injuries that cause ulcers) and even cancers can also trigger this immune dysfunction.

Symptoms
The symptoms of uveitis can be divided into two main groups. The first type presents as a gradual progression of signs that are difficult to detect until the horse shows evidence of vision loss. In this presentation, a low-grade inflammation causes damage over time without causing the horse any significant pain. Your horse will show typical signs of vision loss, such as bumping obstacles, shying unexpectedly and lack of confidence in seemingly simple steering. This form is more common in Appaloosa horses. The acute form is more obvious and presents with pain, redness and discharge. The horse will squint and may rub the eye. The eyelid may be swollen. This inflammation can be cyclical and can be seasonal with periods of discomfort.

Diagnosis
The diagnosis of uveitis is largely based on clinical signs. However, specialist veterinary ophthalmology can often ensure an accurate diagnosis with specialist equipment needed to rule out all other conditions. Special stains, and ultrasound may be required to rule out external conditions, such as ulceration of the surface of the eye, or deeper structural conditions. Blood chemistry can also provide a window into the immune reactions. Tests to determine causes, such as bacterial or viral, may also be useful.

Treatment
Treatment of this challenging condition is largely based around controlling the immune system dysfunction. Corticosteroids are the cornerstone of this treatment and are often applied to the eye’s surface, injected under the conjunctiva or systemically by injection. Other drugs are often given to provide some relief of symptoms by dilating the pupil and decreasing pain.
Long-term treatment of this condition can be required when no underlying cause like bacterial infection can be found. As using corticosteroids is not a safe long-term proposition, small implants under the conjunctiva of the eye have been developed to modify immune system reaction and inflammation associated with this challenging condition.

Of course, we can arrange a referral to a veterinary eye specialist- just ask us. We are fortunate that one of the Sydney eye specialist clinics is coming to visit us at Orange Vet Hospital again! They will next visit in late October. See the section above. Let us know if this is something that you would like us to explore. 

Most sheep properties have resistant worms to one or more sheep drenches. Using effective drenches is key to controlling worms and maintaining a healthy and productive sheep flock. Farmers either breed resistance on their farm with the ongoing use of ineffective drenches, or they buy resistance in with new purchases on the farm.

When choosing a drench to use on your farm, Wormboss recommends three principles:

1. Use the most effective drench for your property.
2. Use an effective combination of two or more drench groups.
3. Use short acting treatments and restrict the use of persistent products for specific purposes and high worm-risk times of year.

To assist Australian sheep producers with selecting the correct drenches, Zoetis has created a website called SheepTRAX. The website is a database showing the prevalence and geographical distribution of drench resistance. The data has been generated from hundreds of on-farm drench resistance tests (FECRT) across all sheep producing areas in Australia. Sheep producers can use this data to:

• Improve knowledge of drench resistance.
• Assist in making informed decisions of what drenches to use.
• Assist in understanding the likelihood of resistant worms in purchased sheep.

SheepTRAX aims to help put research behind your drench selection, helping to maximise your return on investment.

Downer cows can be time consuming and labour intensive, but can have good outcomes. At this time of year, grass tetany, calving paralysis and trauma, for example, splaying legs in slippery hilly paddocks, can all trigger a downer cow situation.

When cows are down, there are a number of secondary injuries that can occur, including neurological changes, pneumonia and metabolic issues. For all of these reasons, as well as ow welfare, it is important to get cows up as soon as possible.

If the cow is bright and alert, nursing care and medications may be enough to get her on her feet again. If she is lethargic, dull or notably abnormal as well as being on the ground, then it is prudent to arrange a prompt veterinary visit to get to the correct treatment as soon as possible.

Golden Rules for nursing care:
Maintain dry, soft, non-slip bedding
Bring feed and clean water to her
Move the cow from side to side every 3hours, and try to maintain her sitting up on her chest- hay bales can be helpful for propping her up. A horse halter can help to control her head while moving her.
Check the udder regularly for heat or swelling suggestive of mastitis
Use lifting devices to stand her

Dairy Australia has made a helpful guide for managing downer cows. Although the photos all have dairy cows, the principles of management are the same for beefy bovines.