Thursday 15 October 2015

Equine Thrush

Thrush

Definition

Thrush is a degenerative condition of the Frog caused by anaerobic bacteria characterised by a grey/black necrotic material in the affected area.

Anatomy

Thrush affects the Medial/Lateral & Central Frog clefts

Causes 

Thrush is caused by Unhygienic conditions where anaerobic bacteria can thrive, the bacteria Spherophorus Necrophorus is most commonly found.  The contribution factors to this are;

Unhygienic Conditions
Poor Stable management
Poor grazing
Unclean Feet
Prolong use of sole pack & pads
Irregular Shoeing or Trimming
Long term use of Heart Bars

Clinical Signs

The Clinical Signs of Thrush are

An Offensive odour
Black/Grey narcotic frog
Increase Moisture discharge
Atrophied Frog
Exposure of sensitive Structures
Lameness
Sheared Heels ( in Sever long term cases )

Diagnosis

Diagnosis is based on clinical finding

Treatment


Veterinary 

Veterinary treatment in not normally needed unless infection is sever.

Farriery 

Farriery Treatment is aimed at removing the cause and limiting the cultivation of the bacteria. This can be done by;

Improving Stable Management
Removing all necrotic materiel
Treating with anti-bacterial sprays and Powder 
Regular Trimming and shoring 

   

  The foot should be well trimmed and as clean as possible. With extra attention being paid to the frog clefts. The frog should then be scrubbed with an iodine solution and flushed with hydrogen Peroxide to kill any anaerobic infection.Finally the food should be cleaned and dried with regular use of a hoof pick and anti-bacterial sprays advised.The use of bar shoes and Sole Pack is also ill advised as they can create a low oxygen environment that advantageous for the growth of bacteria. 

Prognosis


A Good Prognosis can be given as long as there is no extensive damage to the underling sensitive structures.





Equine Abscess



Abscess

Definition

An abscess in an infection & inflammation within the horny foot that can cause acute lameness due to the pressure build up from the formation of puss with or without gas pockets.
There are 2 types of abscess.

            Sub Solar Abscess -
A sub solar abscess in an infection between the horny sole and sensitive sole
            Laminal Abscess (Sub Mural) -

A laminal Abscess is an infection between the horny wall and the sensitive lamina (dermal laminae)

Anatomy

The anatomical structures involved with Abscesses are
*      The Horny Sole
*      The Horny Wall
*      Sensitive Sole
*      Sensitive Laminae
*      White Line

Causes


Common Cause of Abscesses are
*      Solar penetrations by foreign object
*      Sole Pressure
*      Suppuration Corns
*      Fractures
*      Nail Prick
*      Laminitis


Clinical Signs

There will be a variable degree of lameness depending on the size of the abscess and the amount of pressure being places on the sensitive structures caused by the underlying infection, this can be a mild lameness to a no weight bearing limb.
There will be heat within the foot and swelling around the coronary bend and fetlock due to the infection, a strong digital pulse can also be felt over the Medial/Lateral digital arteries.  In the later stages of infection there will be a pungent smell from the foot and the possibility of sinus tracts on the sole or horny wall.
With Sub Mural abscesses the infection can track up the horny wall and erupt out of the coronary band causing a interruption in the hoof wall production and will travel distally as a horizontal crack.

Diagnosis

The Diagnosis of an abscess is first done by examining the foot for penetrations and light pairing of the sole, most of the time there can be obvious sinus tracts that will shoe as a black puss coming out of the sole. If an abscess is present the a pungent smell can also be smelt when examining the foot.
light palpitation of the foot by hand looking for a pain response, and the careful use of hoof testers is also a good way of finding the exact area of infection. light exploration can be carried out and if a high pressure tract is relived the puss will spurt out and an immediate relief can be seen by the horse.
if the abscess is from a nail prick then the use of hoof testers on each clench will show signs of a pain response on the offending nail, when the nail is removed then a black smelly puss can be seen on the nail shank.
if the horse is acutely lame but no abscess can be found after light pairing of the sole then the use of a poultice to soften the feet and dray the infection out can help speed up diagnosis
 



Treatment

     Farrier Treatment

Once an abscess is located then it can be drained by the use of a hoof knife, (searcher knives are useful as they allow for very accurate work ) this will relive the pressure build up within the foot and allow for the abscessation area to be cleaned.
The use of Hydrogen Peroxide can be advantageous due to the foaming action and the high oxygen content. then the tract can be cleaned with a dilute povidone solution or soluble metronidazole,
Hot tubing of the foot twice a day with a saturated solution of salt or Epsom salts  can be beneficial for horses with multiple tracts of infection. then use of a hot poultice for 12-24h after will ensure all the infection is removed, a dry poultice can then be used to allow the foot to harden and also protect the area from re-infection 

            Shoes

When the tract has stopped draining then a well fitted wide webbed shoe that has been seated out will allow for good support of the foot and protect the remaining horny foot, the use of pads can be useful in some cases to protect the sole from re infection. however there is still a risk of re infection from contaminates becoming trapped between the healing sole and the pad. The ricsk of re infection can be reduced by using a solar packing material. 


*      Veterinary Treatment  

A vet will be able to administer Non-Steroidal Anti-Inflammatory drugs that will help reduce the amount of inflammation and help reduce excessive loading on the other limb.  antibiotics are not normal given for an abscess that is not draining as this can extend the time it takes for the infection to erupt , but if it is thort that the infection is close to the distal phalanx then they can be used to protect then underlying structures.

Prognosis

An excellent prognosis can be given in the majority of cases and the horse can return to steadily be normal work. But horses with poor foot quality can be prone to reassurance.


Stud Holes in performance horses


The use of Studs in Polocrosse


Polocrosse Vs Polo
Unlike polo, polocrosse horses are stopping and turning on much tighter circle than polo ponies that run a fast long line, this tighter game has a huge effect on what happening inside the limb.

Wants happening inside
When a polocrosse horse dose a sliding stop with studs in, the outside of the shoe will have more grip over the inside twisting the limb through the lower joint and hock placing an naturally high twisting force through the joints and ligaments all the way down to the underlying bony structures., where a shoe without studs will still twist out this is because of the hocks and not the stud in the shoe.

The Effects
Because of the uneven loading that one stud places on the biomechanical structures of the lower limb Studs can have detrimental effects on the horses foot and the ligaments & tendons of the Distal interphalangeal joint (Fetlock Joint) and Proximal Interphalangeal Joint (Pastern Joint). This can result in ligament damage or even broken bones.