EQUINE | CPD Article
EQUINE | CPD Article
Other rare infections can be caused by Clostridial infections , including C . botilinum and C . tetani , the latter especially in unvaccinated animals . Myositis , necrotizing cellulitis and systemic toxaemia may also follow . These are potentially life threatening conditions and should be treated aggressively and intensively . 3
Septic Peritonitis Non-septic , sub-clinical peritonitis is a common occurrence post castration due to the communication between the vaginal and peritoneal cavities . Nucleated cell counts of peritoneal fluids of up to 10 X 109 / l for as long as five days after the castration have been demonstrated without clinical signs of peritonitis . 10 ( A diagnosis of peritonitis is usually made in the presence of a nucleated cell count of more than 5 x 109 / l4 or 10 x 109 / l2 .) Therefore the abdominal fluid must be cytologically evaluated for degenerative neutrophils or the presence of bacteria if septic peritonitis is supected . 10 Septic peritonitis after a castration is a rare complication . In retrospective studies from Europe , USA and Hong Kong , accounting for almost 800 castrations , no horses were reported to have developed peritonitis after being castrated , 4 , 5 , 7-9 although one case was suspected to have developed an inguinal abscess . 8
Clinical signs of septic peritonitis include pyrexia , colic , diarrhoea , tachycardia , reluctance to move , anorexia , decreased habitus and weight loss . Cytological examination of peritoneal fluid will reveal degenerative changes in the neutrophils . Intra- or extracellular bacteria may also be seen in severe cases . Intensive treatment needs to be instituted , including broad spectrum antimicrobial therapy ( pending culture and antibiogram results ), NSAIDs and anti-endotoxic treatment . In severe cases an indwelling abdominal drain with frequent abdominal lavage may be needed . However , generally the prognosis for horses with a known cause of peritonitis is poor . 4
Hydrocoele A hydrocoele or vaginocoele is an idiopathic accumulation of a sterile amber-colored fluid within the vaginal cavity . It will appear as if a testicle was left behind . However it is a soft , fluctuant swelling and the fluid might be reducible into the peritoneal cavity . 1 The condition may become apparent months to years after the castration and is associated with open castrations because of the non-removal of the parietal tunic . Mules are predisposed to this complication . Although it may be esthetically unacceptable to the owner , it is of no clinical relevance . Drainage will only temporarily alleviate the swelling . Treatment consists of complete surgical removal of the cyst-like structure . The incision can be sutured or left to heal by secondary intention . 1 , 10
Penile Damage The shaft of the penis can be mistaken for a testicle , leading to significant damage to the penis . Such a patient need to be referred to a surgical facility for surgical repair or a partial phallectomy . 3 If the fascia surrounding the penis is sufficiently damaged , it may cause soft tissue swelling and paraphimosis . 3
Incomplete Cryptorchid Castration 10 The presence of a small inguinal testicle must be differentiated from the tail of the epididymis or the gubernaculum remnant . The gubernaculums testis is a mesenchymal cord extending from the caudal pole of the fetal testis , situated caudal to the kidney , to the scrotum . The role of the gubernaculum is to guide the descending of the testicle . Around day 45 of gestation , the peritoneum evaginates through the inguinal canal , around the extra-abdominal portion of the gubernaculum to form the vaginal tunic . During this period , the testicle enlarges to its maximum size at 5 months ( up to ten times the size at birth ) because of multiplication of the interstitial cells . Around the fifth month , the epididymis descends into the vaginal
18 • Equine Health Update •