Sunday, August 25, 2013

Three things I learned: veterinary care of backyard chickens

This chicken presented with a nice bright comb, but she was quite depressed and straining to lay an egg.
Chickens are just delightful. I don’t treat many of them but they are always absolutely gracious patients and they are staggeringly beautiful. I am trying my best not to overdose on webinars, but when the Centre for Veterinary Education announced a webinar on backyard chickens, no wasn’t an option.

Well known avian and exotics luminary Dr Michael Cannon, of Cannon & Ball Veterinary Surgeons, gave a fact-packed presentation.

One point he made was that most backyard chickens (BYCs) produce eggs for around three years…but they live well beyond that (8-10 years). So urbanites who adopt chooks as an ethical source of eggs need to cater for their long retirement. (Another point he made – which I had not thought of as most of my chook-owning clients say their chickens are companions) is that as veterinarians we need to be mindful to ensure that a withholding period is observed if people intend to eat their chickens. i.e. chickens can’t be consumed within a certain time period (e.g. 7 days for amoxyl and14 days for trimethoprim-sulfa drugs).

  1. Egg binding occurs due to oversized eggs, overproduction of eggs, dietary deficiencies (calcium & vitamin D3), shell gland infections and when hens are too old to lay. Dr Cannon’s medical treatment for egg-binding consists of placing the patient in a warm, dark, humid environment; giving fluids (usually Hartmanns – PO/SC/IV or intra-osseus); calcium (50-100mgkg/IV or slow IM); oxytocin (5 IUkg IM with a repeat dose 30minutes later if required) and the surgery if no response within 12-24 hours.
  2. Healthy chickens have a bright eye, clean beak, nice plumage, an evenly coloured and reasonably erect comb and a generally bright demeanour. The best way to assess their hydration is the feel the skin over their pectoral mass and slide it side to side. If they are well hydrated this feels smooth, but if they are dehydrated it can be quite sticky. Subcutaneous fluids can be given between the shoulder blades or in leg fold in the inguinal region.
  3. Scaly-leg is probably due to the Cnemidocoptes mite which probably thrives in immunosuppressed chickens. It can be treated orally with ivermectin (200-400micrograms/kg; dose each 10-14 days until resolved).

But thanks to some medical treatment...out it came. 
The webinar also covered much about common respiratory diseases and conditions such as heavy metal poisoning, treatment of scaly-leg (probably due to immunosuppression) and feeding BYCs.