STEVENS - PINK-BACKED PELICAN



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is not during the first week after hatching, but later when competition for

food is evidentally severe and the danger of falling from the nest is at its


greatest (Johnsgard, 1993).


Problems during rearing


During the hand-rearing of this species at Longleat, a recurrent problem

has been the premature death of chicks between six to 17 days old due to

yolk retention. Of the 26 premature deaths that have occurred since 1998,

15 were from suspected yolk sac infection; this included one bird which was

being reared by its parents. Tierpark Berlin did not list this or any other

problems when answering the questionaire.


The symptoms that appear to be synonymous with yolk sac infection

include:


Fits/convulsions.


Regurgitation.


Hanging head over side of nest bowl.


Laboured breathing.


Loss of appetite.


Lethargy between fits/seizures.


Pecking at air in a gulping fashion.


Various methods of managing this infection have been employed over

the years. All chicks are given an antibiotic for the first three weeks of their

life. The antibiotics used have changed over the years. At present Synulox

palatable drops are given three times a day for the first 14 days at a rate of

0.25ml/kg. The antibiotic is then changed to Baytril 2.5% oral solution

given at a rate of 0.4ml/kg. The change is to prevent resistance to any one

antibiotic. The new feeding regime that has been implemented is also aimed

at combating yolk retention. One of the chicks reared in 2005 was given

an ultrasound scan at 12 days old to see if the yolk had been retained. This

proved negative. An unobtrusive yolk sac removal operation can be carried

out, however there is an element of risk during anaesthesia and from post¬

operative infection.


Other problems have included regurgitation and deformed legs. The first

can be a symptom of yolk retention, but may also be a sign of overfeeding.

Leg and foot deformities were an issue in 2001, when chicks developed

brittle bones and splayed legs. Husbandry techniques were changed (i.e.

the diet and the proper administration of vitamin and mineral supplements,

plus the use of lime twigs in the nest baskets and crates), since when there

have been no further incidences of this problem.



