These are some brief notes on equine therapeutics, to cover broad principles and contraindications, doses are not given in most cases and should always be checked before administrarion... Remember that horses and donkeys have metabolic species differences and may require different doses.
Body Weight KG = Length cm x Girth cm 2 12 000
Fluid maintenance requirement 50ml/kg/day Replace losses like with like ie match the fluid and electrolytes to the losses Acidosis, alkalosis rehydrate! the kidney will then restore the acid/base balance Sweat loss of Na, Cl, Ca Diarrhoea, anorexia loss of K Stress, lactation loss of Ca
66% body weight water of that 66% ICF 33% ECF 25% of ECF is plasma Ie blood approx 10% of body weight Dehydration 7% dry mucus membranes, skin tenting 10% raised PCV 12% sunken eye cold limbs tachycardia
Intravenous fluid therapy Sterile catheter management Frequent flushing with heparin saline to avoid thrombus formation Large bore catheter 10 or 12 gauge, stab incision ensure catheter security! Risks air, thrombus and catheter embolism Jugular vein deeper in donkey
Plasma Useful therapy in diarrhoea and septicaemia providing... Fluid Albumin Antithrombin3 Fibronectin C etc Sterility important
Sedation Alpha 1 adrenergic blocker ACEPROMAZINE Alpha 2 adrenergic agonists ROMIFIDINE DETOMIDINE XYLAZINE Benzodiazapines DIAZEPAM MIDAZOLAM
Wound Lavage Iodine 0.1% 1:100 of 5% 5% for EZL Chlorhexidine 0.05% 1:40 of 2%
Opioids BUTORPHANOL Partial agonist Synergistic with alpha2 agonists Analgesic CODEINE 1-3 mg/kg antidiarrhoeal
Anaesthetics KETAMINE Dissociative anaesthetic Good induction and recovery after alpha 2 agonists Barbiturates THIOPENTONE 10 mins anaesthetic Poor induction and recovery Inhalation anaesthetics ISOFLURANE HALOTHANE SEVOFLURANE
Anaesthetic Donkeys and Mules Alpha 2 agonist mules require 50% more alpha 2 agonist than donkeys or horses Butorphanol Ketamine increase dose by 20% Less obvious signs of lightening anaesthesia than a horse
Antibiotics Trimethoprim sulphadiazine (gram ve and +ve) Gentamycin, Amikacin (gram ve) Penicillin (gram +ve) Metronidazole (anaerobies) Ceftiofur/cefoquinome (Gram ve +ve ) Fluroquinones (gram +ve and Gram ve)
Antibiotics in donkeys... Penicillin, gentamycin, trimethoprim sulphadiazine Metabolised faster than in horses. Need more frequent dosing
Antiprotozoals Diminazene Resistance Low therapeutic index Anaphylaxis Local reactions IMIDOCARB Local reactions Toxic in donkeys and mules
Antifungals Enilconazole (Imaverol) Natamycin (Mycophyt) Miconazole (Malasseb) Amphoteracin B 5% Povidone Iodine KI 10mg/kg q 24 PO
Non Steroidal Anti-Inflammatory Drugs NSAIDS Cyclo-oxygenase inhibitors Anti-prostoglandin Anti-inflammatory Antipyretic Analgesic Antiendotoxic Foals.. Increased risk of... gastric ulceration,renal toxicity
PHENYLBUTAZONE safe long term but small risk renal toxicity and colonic ulceration FLUNIXIN MEGLUMINE very good visceral analgesic and anti-endotoxic FIROCOXIB COX 2 specific,less risk gastric ulceration MELOXICAM less gastric ulceration CARPROFEN don t use in donkeys DIPYRONE anti- spasmodic with hyoscine in Buscopan ASPIRIN oral powder
NSAIDS in donkeys and mules Short t1/2 compared to horses, twice daily dosing Except Carprofen... Avoid this in donkeys!!!
Corticosteroids Prednisolone 1-5mg/kg PO, occular preps. + (safest) Dexamethasone 0.1mg/kg i/v i/m + + + Triamcinolone intra-articular 10 mg/joint + Beclomathasone inhaled + + Anti-inflammatory, enhance vasoconstriction, mobilise fat, immunosupression, muscle loss.
Antihistamines Premedication against potential anaphylaxis For treatment of allergic conditions Not helpful in RAO Skin allergies?
Sympathetic nervous system Sympathetomimetics Alpha 1 vasoconstriction smooth muscle Phenylephrine Alpha 2 neurotransmitter inhibition Detomidine,Romifidine,Xylazine Beta 1 myocardial contraction Dobutamine. Dopamine, Adrenaline Beta 2 vasodilation smooth muscle relaxation Clenbutarol, Salbutamol DOPA 1 DOPA 2 vasodilation diuresis Sympathetolytics Acepromazine
Parasympathetic nervous system Parasympathomimetics Neostigmine Bethanechol Pilocarpine Parasympatholytics Atropine Hyoscine
HORMONES Altrenogest to prevent oestrus GNRH Buserelin to stimilate ovulation Chorionic gonadotrophin (chorulon) to stimulate ovulation Cloprostanol PgF2 Alpha to cause luteolysis Oxytocin to cause uterine contraction and milk let- down
Adrenaline 1;1000 3-6ml slow i/v Anaphylactic shock Cardiac resuscitation Crash Kit available for emergency use... Have drugs drawn up and labelled Or Doses on laminated sheet in mls/kg
Amitraz (CNS side effects) Amoxycillin (local reaction) Monensin ( myopathy, myocarditis) Lincomycin (Severe Diarrhoea) Tylosin Imidocarb (toxic to donkeys and mules)