The digestive system of rabbit roughly correspond in their parts to those frog but each region is more developed and the division of labour reaches a higher development of rabbit .The digestive system is concerned which is a complex process consisting of all changes which occur in food with the alimentary canal from the time it is taken into the mouth until it has been built up into actual body substance or used to supply body energy .These changes may be arranged in order under four heads ;[1] digestion [2] absorption [3] distribution [4]assimilation . The digestive system of the rabbit consists of alimentary canal and associated glands such as liver and pancreas that are situated outside the alimentary canal but pour their secretion into it . ALIMENTARY CANAL ; Since the rabbit is hervivorous ,its alimentary canal is very long coiled tube , begining at mouth and end at anus .Starting from the mouth end , it consists buccal cavity , pharynx,oesophagus ,stomach ,small intestine and large intestine . BUCCAL CAVITY The mouth of rabbit is terminal and relative small .It is bounded by the lips which are movable .The upper lips is divided in middle to expose the incisor teeth ,a condition which is the advantage in gnawing .The buccal cavity is seperated from the respiratory channel by the palate which form s somewhat arched roof of the mouth cavity has the skeletol foundation of the horizontal processes of the premaxillae ,maxillae and palatine bones .It is known as the hard palate ; its hinder part , which is purely formed by connective tissue and muscles , is called the soft palate , the free border of which projects into the pharyngeal cavity .The surface of the entire palate particularly that of the soft palate is provided with numerous palatine glands whose secrrtion of mucus helps to keep the mouth cavity moist The hard palate is also provided with palatine ridges or rugae [most well -developed in carnivores ] which give a washboard -like character to the palate thus help in securing a surer grip of the food .In the anterior part of the mouth cavity there are two very smalll naso -palatine openings which join the buccal cavity with the nasal cavity .The posterior internal nares lie at the posterior end of the soft palate and open into the hinder part of the nasal chamber .The glottis is situated under the floor of the pharynx and leads into the trachea .Its opening is guarded by a bilobed cartilaginous flap the epi glottis, which prevent food from entering the wind pipe or trachea .The eustachian tubes open into the posterior nasal chamber . The muscular and slightly protrusible tongue lies along the floor of the mouth cavity and is attached just in front of the hyoid and is directed forward .The tongue is subdivided into the hard posterior part and the soft anterior portion. The side of the posterior part bears the foliate papillie.On the upper surface of the hard region are teo circumvallate papillae, each with the ring like depression round it .On both of these papillae and also on the tip and sides of the soft anterior portion taste buds are collected .Since the tongue is capable of great variety of movements ,it serves many useful proposes .It is auniversal- tooth brush .In furred animals ,it also act as a curry comb .The mucous membrane coverig the tongue has numerous minute finger shaped papaillae which contains nerve cells and hence do the work of organs of taste .
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