Page 594 - WSAVA2018
P. 594

 25-28 September, 2018 | Singapore
Oral cavity
The oral cavity should be examined for diphtheritic plaques or other abnormalities. Its colour should be noted; it is normally pale pink.
There should not be bruising or haemorrhage visible. The abdomen can be trans-illuminated with an intense focal light for closer inspection. As the chick grows, the abdomen reduces in size relative to the rest of the body. It should be concave when palpated; a convex abdomen could indicate a degree of abdominal distension.
Feather growth
Abnormalities include:
· Feathers erupting in an unusual pattern (e.g. in a circular pattern on the crown of the head, rather than running parallel along the line of the body).
and treat this problem without seeking to understand the underlying pathology.
Causes include:
· Generalized ileus (e.g. systemic illness, foreign bod- ies, chilling, heavy metal toxicosis, dehydration).
· Crop disorders (e.g. foreign bodies, overstretched/ atonic crop, infectious ingluvitis, fibrous food impac- tion, or crop burns).
· Dietary problems (e.g. cold food, excessively watery food, food that settles out in the crop, overfeeding, overly dry food).
Clinical presentation
Signs include the crop failing to empty in more than six hours, regurgitation and loss of feeding response. Most chicks will be dehydrated on presentation (erythematous wrinkled skin, tenting of the skin and sunken eyes).
Aspiration of the crop contents usually reveals the sour –smelling fermenting ingesta (‘sour crop’) or thickened ingesta (hand-rearing formula with the fluid drawn out of it).
Faecal output may be reduced, and the stool may be unformed or pasty.
This is based on crop and faecal cytology (Gram stain) and culture, haematology and biochemistry, and radiography.
The cause should be identified using the means outlined above, and corrected where possible.
The crop should be emptied with a feeding tube and repeatedly lavaged with warm saline until a clear wash has been obtained. (In some extreme cases, e.g. foreign bodies, it may be necessary to perform an ingluviotomy.) It should always be assumed that these chicks are dehydrated, and they should be treated with parental fluids until crop motility has been restored.
Appropriate antimicrobials should be given as indicated by crop and faecal cytology/culture. It is overly simplistic to assume that these cases are always yeast infections; in the author’s experience bacterial overgrowth is usually more common.
A crop ‘bra’ can be used if needed. This is a non- adhesive bandage placed under the crop and around the wings to ‘lift and support’ the atonic crop in order to allow gravity to assist with crop emptying.
Once the crop has been emptied, in many cases it may be advisable to leave it empty for a few hours while dehydration is corrected. Initial feeds should be of small volumes of isotonic saline. If this moves through, solids can be added. Small, watery meals should be
· Stress bars in the opened vane.
· Abnormal colouring.
· Haemorrhage in the calamus.
· Dystrophic development.
The faecal portion should be relatively well formed, light brown in colour, and not malodorous. A degree of polyuria is normal (especially in hand-reared chicks), but this should lessen as the chick ages. Excessive or persistent polyuria warrants further investigation.
Diagnostic testing
Microbiology is an important tool in assessing gastrointestinal flora. Gram stains and cultures are frequently used to assess crop or other gastrointestinal problems. Normal bacterial flora includes Lactobacillus, Streptococcus, Staphylococcus and Bacillus spp. Low numbers of E. coli are often normally cultured as well. Other gram-negative bacilli and Candida are rarely cultured from healthy chicks.
Clinical pathology can be used readily on chicks. It is important to note that compared to adults of the same species, chicks normally have:
· Lower PCV and higher white cell count.
· Lower total protein and uric acid.
· Higher CK.
Radiography is an essential tool for assessing the status of the skeletal system, but the low density of the bones and the cartilaginous growth plates in very young chicks can make this difficult.
Common problems
Crop stasis (‘sour crop’)
This is a commonly seen problem in paediatric medicine, with most sick chicks having varying degrees of crop stasis. All too often hand rearers attempt to diagnose

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