Jeffrey Low
email: jeffctlow@yahoo.com



Tuesday, August 4, 2009

MY THOUGHTS ON VITAMINS A AND B-COMPLEX IN THE CAPTIVE SHAMA'S DIET

From the more common ailments that affect the captive shamas, I think it is likely that they could have higher requirements for certain vitamins than other softbills that we keep in this region. It could also be likely that the usual shama pellets that we use here are deficient in these vitamins.

Hobbyists that have kept shamas long enough, especially those that own a large number of these birds will know that they can be often affected by infections of the eyes and respiratory tracts. I strongly believe that the primary cause of these is a deficiency in vitamin A. Some shama pellets that we use here are subjected to high heat during the extrusion process and this could destroy most of the vitamins from the food ingredients used in these pellets. Vitamin A is very sensitive to heat and oxidation.

Deficiency in vitamin A often causes infection of the eyes in shamas. In severe cases of deficiency, it can result in a condition known as xerophthalmia. Captive shamas are known to exhibit the characteristic symptoms of this condition with accumulation of fluids and sticky discharge from the affected eye, often causing the eyelids to crust together. A severe deficiency of vitamin A will cause keratinization of the conjunctiva and inadequate lubrication of the cornea, resulting in this condition which can lead to blindness in shamas.

The mucous membranes of the respiratory tract are also frequently first to be affected by a deficiency in vitamin A. Diminished mucous production from a deficiency in vitamin A will result in pathogenic invasions of the mucous membranes of the respiratory tract, with symptoms of coughing, sneezing, wheezing, clogged nostrils, etc.

A condition known as bumblefoot although not common, can sometimes affect the captive shama as well and the primary cause is also likely to be due to a deficiency in vitamin A, resulting in the infection and inflammation of the balls of the feet.

I always gut load my live feeder insects with carrots and leafy greens which are rich in beta-carotene and I think this is one way of supplying some vitamin A through the diet. Another alternative is to smear feeder insects with red palm oil, one of the richest sources of carotenoids. The enzymatic conversion of dietary carotenoids to vitamin A is regulated according to need of the bird and high consumption of carotenoids does not usually cause toxicity. For so many years, ever since I had started on this regime of ensuring some form of vitamin A is supplied to my caged shamas in these ways, I had only one bird that has succumbed to respiratory infection and it was during the molt when the immune system was much weakened. My molting birds are now further supplemented with multi-vitamins, twice weekly.

Deficiency in the B vitamins can cause lost of appetite, lethargy, hyper-excitability and in more severe cases, convulsions in shamas. B vitamins can be supplied through the pellets by sprinkling and coating them with brewer’s yeast each time the food cup is refreshed, preferably on a daily basis, as prolonged exposure to light will destroy the B-vitamins. De-bittered brewer’s yeast has the bitter taste removed and will be more palatable to the birds. Another way is to smear liquid B-complex vitamins on feeder insects that are to be fed to the birds, on a daily basis. I have already started to practice these, as advised by an experienced shama keeper and so far, although too early to be conclusive, I have not experienced any more convulsions.

Some imported pellets are scientifically formulated and well fortified through a process using the more stable forms of artificially synthesized vitamins, usually at many times the level of what is deemed to be the minimum requirement of our birds. These pellets I would think do not need to be further supplemented during maintenance, if they constitute the major part of the bird’s daily diet.

2 comments:

  1. Hi Jeffrey,

    It is always with great pleasure to read your articles. I would opined personally that they reveal all aspect and is very technical. I should say you are very straight forward in guiding the way to take by making things look simple to follow.

    I have been following your blog to gather info. for myself and friends. Have a good day and good health always.

    abd. nasir, miri, sarawak.

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  2. cool.. great info

    ReplyDelete