Friday, June 6, 2008

The Molting Process

written on November 18th , 2006

Every adult shama will need to undergo a yearly cycle in its development if it is to be healthy and be able to perform well. The cycle commences with the annual moult when, over a period, the bird sheds and replaces all its feathers. As the moult nears completion, the bird's form (i.e. its breeding condition) will start to rise in preparation for the breeding season.

The form should continue to rise over a period of 2 months or so after the moult until the bird reaches its peak breeding condition. The male will then take over the territory of a weaker male, or, if he already has an established territory, he will warn other males against intruding into it. He does this by patrolling his territory and singing his loud territorial song especially during the morning and evening.

Having secured his territory, the male will then pair with a female. They will build their nest and rear their young. In the wilds, the pair will probably raise 2 or 3 clutches. By the end of the breeding season, the physical condition of the birds will have started to deteriorate. This deterioration will eventually lead to the moult and the whole yearly cycle will start again.

Many enthusiasts only provide their shamas with more nourishing food than the daily fare when the molt has already commenced. I think this is wrong. For the moult to commence, the shama’s brain must issue a signal that the food required for a successful moult is plentiful and that the moult should start. This signal is issued in the form of hormones being released into the bloodstream that cause the new feathers to grow. As the new feathers grow, they push out the old feathers which fall off.

When the brain feels that the quantity or quality of the food is insufficient for a good moult, it does not release the hormones that are required for the moult to commence or only a little hormone may be released for a short period or sporadically. The moult may thus be delayed, it may be sporadic, or the bird may only experience a partial moult. In such case, the bird's yearly cycle is interrupted and the hormones necessary to bring the bird into top form are not released or insufficiently released. Such a bird does not perform well and the owner wonders why his bird’s form does not go up after the moult.

If the nutrition of the bird leading up to the moult is correct, the 2 primary tails (i.e the longest tails) will shed on the same day. At most, there should be only one day between the shedding of the first and second primary tails. If there is several days delay, the consequence will be that one of the tails will be longer than the other. As the tails grow at the rate of approximately 4� a month, it will be appreciated that a delay of even one week will likely result in one of the primary tails being an inch or so longer than the other.

When the quantity or quality of the food is inadequate even for one day during the moult, the result may be seen in the semi-transparent lines running horizontally along the tail or wing feather. These lines are known as ‘stress lines or fault lines. They are caused because the feather continues to grow regardless of whether or not the nutrition is adequate for its growth. The result is that there is a gap in the development of the growing feather and this is represented in a stress line. This is a weak spot in the feather and it will tend to break at this point in due course. If the feather has no weak spots, it is quite strong and flexible and should last in good condition until the next moult is due.

Feathers are comprised mostly of protein and there should be lots of good quality protein available to the bird at all times during the moult. The feeding of small invertebrates (animals with backbone) such as frogs, fish, skinks (sand lizards) lizards etc will help to ensure that the bird receives the quality protein that it needs. Insects such as crickets and mealworms contain much fat and comparatively less protein. While they should be fed as part of the bird's diet during the moult, feeding them solely to the bird may adversely affect the moult. Grass-hoppers, because they have more protein and less fat are more suitable for the moulting bird. As in everything, there will need to be balance and the greater the variety of live food that you are able to provide to the bird, the more likely it will be to have a good moult.

What about the suitability of dry food? In my experience, no dry food currently on the market completely meets the requirements of the shama. My practice when feeding dry food is to feed solely dry food from morning until early evening and then provide a variety of live food to the birds for the rest of the day. Using this method, I have successfully moulted long-tailed shamas though I prefer to feed only live food to the males during the moult.

As the shama will need to consume a great deal of protein and other food for feather growth, the vitamins and minerals that assist the body to process and assimilate them will need to be provided in adequate quantities. A multi-vitamin and mineral supplement should be provided to the birds during the moult. Of the vitamins, the B Complex vitamins are the most important. Vitamin B6 helps to metabolize the protein and B12 gives the bird appetite and also assists in digestion. An oil based supplement such as vitamin E or wheat-germ oil should be provided 3 to 4 days a week to obtain a glossy shine on the feathers. Without adequate vitamins the bird eats less as it is unable to process the food (and especially the protein) properly. Such a bird lacks energy and appears listless. This may give the false impression that it is tame.

During the moult the bird will not be active as all its energy will be directed towards the moult. If it is kept in a cage, the cage should be partially covered with a cloth and placed in its usual spot so that the bird has a quiet time during the moult. If possible, bathing facilities should be provided daily. Wetting the feathers softens them and assists growth. Preening of the feathers by the bird will also help to remove the sheath from the growing feather and assist in its development.

During the moult, try to do the following:-

1. Keep the cage half covered with the cage cloth cover.

2. Keep the cage in its usual place in the house that the bird is already familiar with and likes.

3. Do not take the bird to bird gatherings or hang its cage in the garden etc. The moult should be a time of rest and rejuvenation while the feathers are changed.

4. Make sure that the place where the shama is kept is cool as shamas cannot take much heat.

5. Provide bath facilities once a day. This encourages the bird to preen and this helps the feathers to grow.

6. Ensure that the bird receives sufficient protein in its diet. Protein is especially important as the new feathers are made up mostly of protein. If possible, feed only live food or supplement the dry food with a variety of live food.

7. A good vitamin and mineral supplement should be given to the birds. In addition, B Complex should be given 4 to 5 times a week and Vitamin E in oil form should be given 3 times a week. The oil makes the feathers glossy.

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