By the time of hatching, the residual yolk sac (RYS) should be
completely internalized into the body cavity of the chick through
the navel, then the navel should be completely closed (healed).
After hatching, the RYS contents are used for general
growth
including growth of the small intestine. The aim of this study was to
verify if there is any effect of navel condition on the growth of
small intestinal villi. Jejunum samples from 200 new hatched
chicks (at the age of 1 up to 5 days), with the average of 20 chicks
per day were obtained, and divided into 2 groups: healed navels and
unhealed navels, which were collected and studied histologically.
For the first time, this study demonstrated the negative effect of
unhealed navel on the growth of small intestinal villi. The results of
this study also demonstrated by Morphometric Parameters
Measurements of small intestinal villi that the high and the surface
areas of villi were increased in healed navel chicks in comparison
with unhealed chicks.
The research was conducted at Faculty of Agriculture, Damascus University/
Syria, with the help of Scientific Agricultural Research Center in Latakia during
2013 and 2014 seasons. Three rootstocks were used i.e. Sour orange, citrumelo
and troyer c
itrange, to study some factors affecting the success of micrografting
technique (concentrations and periods of sterilization, rootstock, shoot tip size, type
of nutritive medium and the grafting method). The nutritive medium was prepared,
and the shoot tips was isolated from Navel orange source, then the micrografting
was done for the three rootstocks.
This research was conducted during 2010-2011 growing seasons on 15 years old
trees of “Washington Navel” variety grafted on Citrus aurantium (sour orange) stock and
planted in the village of “Al-hinnady” in Lattakia. To determine the appropriate pr
eharvest
and post-harvest treatments to get the most production and better quality of fruits.
