Int. J. Adv. Res. Biol. Sci. (2016). 3(8): 149-159 International Journal of Advanced Research in Biological Sciences ISSN: 2348-8069 www.ijarbs.com Volume 3, Issue 8 - 2016 Research Article SOI: http://s-o-i.org/1.15/ijarbs-2016-3-8-25 Macroscopical anatomy of the air sacs of the turkey Ragab S. A. and *Reem R. T. Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Cairo University, Egypt. *Corresponding author: [email protected] Abstract Because of its physiological importance in the rapid growth rate of birds and the continous air flow that provided it the lungs in both inspiration and expiration, the present study was performed to examine the air sac system on twelve mature turkeys of both sexes and different weight . Seven air sacs were demonstrated associated with the two lungs and characteristic for the turkey. They comprised; the single composite cervicoclavicular air sac and the paired medial clavicular, thoracic and abdominal air sacs. The cervicoclavicular air sac closed partially the thoracic inlet and aerated the coracoid, the clavicle, the sternum, the sternal ribs and most of the vertebral column. The medial clavicular air sacs were the smallest ones, characteristic in the turkey and connected with the preceeding air sac with several small ducts on each side. The thoracic air sac related to the last two ribs, cranially and the abdominal wall, caudally. The medial clavicular and thoracic airsacs had no diverticula and aerated no bones. The paired abdominal air sacs were the largest, interwoven with the abdominal organs and gave off the femoral, perirenal and iliolumbar diverticula as well as the unique pericloacal diverticula dorsolateral to the cloaca on both sides. The abdominal air sacs aerated the synsacrum and the ilium but did not ventilated the femur or any bone of the leg. Keywords: Turkey- Air sacs- Morphology Introduction Dyce et al. (2002) described the air sacs as blind thin- In general, there were a total of eight air sacs located walled enlargements of the bronchial system, extended in the body cavity of the domestic birds, two single beyond the lung in close relationship to the thoracic and three double. The single sacs were the cervical and abdominal viscera. Diverticula from these sacs and clavicular, while the paired ones were the cranial entered some bones and even extended between the thoracic, the caudal thoracic and the abdominal (King, skeletal muscles. O’Malley (2005) recorded that the 1975; Mitchell, 1984; Scheid and Piiper, 1987 and air sacs acts as bellows but do not participate in gas Dyce et al. 2002). However, in some species, the exchange. He added that, the bellows system allows cervical sac was double making nine air sacs (Nickel continuous air flow to the lungs in both respiration and et al., 1977; Baumel et al., 1993; Fedde, 1998; expiration. Duncker, 2004; El-Mahdy, 2005, O’Malley, 2005; Daoust et al., 2008 and Casteleyn et al., 2010). In the embryo there are six pairs of air sacs: cervical, Meanwhile, Bezuidenhout et al. (1999) in ostrich lateral clavicular, medial clavicular, cranial thoracic, revealed five pairs of air sacs; cervical, clavicular, caudal thoracic and abdominal. In nearly all species cranial thoracic, caudal thoracic and abdominal. there is some fusion of the air sacs during the embryonic process or soon after hatching and King and Atherton (1970) revealed seven air sacs in consequently the final number of air sacs in the turkey. The paired cervical sacs fused early with the hatched bird is reduced (King and Mclelland, 1984). primordial pair of the lateral clavicular sacs forming a 149 Int. J. Adv. Res. Biol. Sci. (2016). 3(8): 149-159 single composite cervicoclavicular air sac. The between the body wall and the abdominal air sacs. primordial pair of the medial clavicular sacs persisted The cranial thoracic sac was connected to the third throughout life as a pair of very small separate sacs. medioventral while the caudal thoracic sac was Also, a pair of cranial thoracic and a pair of abdominal connected to the first lateroventral secondary bronchi. sacs were present. They added that the paired caudal Both thoracic air sacs possessed no diverticula and thoracic air sacs were totally suppressed in the early aerate no bones (King 1975, Nickel et al., 1977, Dyce embryo. et al., 2002). Meanwhile, Crespo et al. (1998) recorded that, the turkey had paired single thoracic In mallard duck, Demirkan et al. (2006) revealed the sacs with two ostia in 90 % of the examined general eight air sacs, while in white Pekin ducks, the specimens while in the other 10% the turkey had caudal thoracic sacs were absent, and so six air sacs paired cranial and caudal thoracic air sacs, each with a were present. single ostium, similar to that recorded by Ficken and Barnes (1990) and Ficken et al. (1991). Onuk et al. (2009) in domestic native geese, reported a totally of seven air sacs; a single cervicoclavicular, In the domestic pigeon, El-Mahdy (2005) observed and a paired cranial thoracic, caudal thoracic and that the anterior ends of the cranial thoracic sacs were abdominal sacs. completely fused with the caudal border of the interclavicular air sac, and also attached by two small The cervical air sac consisted of a median chamber, tubes-like connections with the cervical air sacs. situated between the lungs and dorsal to the Moreover, the caudal ends of the cranial thoracic air esophagus, and a pair of tubular vertebral diverticula, sacs were connected by two short narrow tubes with on each side of the vertebral column, which aerate all the caudal thoracic air sacs. the cervical vertebrae, except atlas and axis, and the first two thoracic vertebrae as well as the first two The abdominal air sacs were the largest ones in the vertebral ribs. The cervical air sac was connected chickens, and occupied the caudodorsal part of the dorsally to the first medioventral secondary bronchus celom. Their extensive lateral surfaces were in contact (Nickel et al., 1977, King and Mclelland 1984, Dyce with the abdominal and pelvic walls while the medial et al., 2002, El-Mahdy, 2005 and Demirkan et al., surfaces of both sides enclosed the abdominal organs. 2006, in chickens, pigeon and mallard duck). On the Each abdominal sac gave off several perirenal and other hand, Kurtul et al. (2004) demonstrated that the several femoral diverticula. The former was extended cervical sac of the rock partridge had a caudally along the kidneys and invading the adjacent vertebrae pointed diverticula located between the two lungs. The of the synsacrum and pelvic girdle. The latter latter diverticulum was termed the interpulmonary diverticula invading the muscles of the pelvic girdle diverticulum by Onuk et al (2009) in the goose. and acetabulum but never aerate the femur or any other bone of the leg (King, 1966 and 1975 and In chickens, the clavicular air sac was a large and Duncker, 1975). Moreover, King (1975) added that, complicated sac occupying the thoracic inlet. It the abdominal air sacs detached also two iliolumbar consisted of intrathoracic diverticula which extended diverticula which proceeded through the iliolumbar around the heart and along the sternum, and canal of the synsacrum. In the duck and geese, the extrathoracic diverticula which spread between the abdominal air sac aerated the synsacrum as well as the bones and muscle of the thoracic girdle and shoulder last two or three ribs (Demirkan et al., 2006 and Onuk joint. It aerated the sternum, the sternal ribs, the et al., 2009). humerus and the coracoid. It was connected to the third medioventral bronchus (King, 1966 and 1975, Materials and Methods Duncker, 1971, King and Mclelland 1984andO’Malley, 2005). Moreover, Demrkan et al. Twelveadult baladi turkeys of both sexes and different (2006) revealed that, in Japanese quails, the humerus weight were slaughtered and allowed to and the sternum were not aerated and the pneumatic exsanguinate.The trachea of six birds was injected by foramina were absent. latex neoprene. The specimens were fixed in 10% formalin for 3-4 days and then dissected. In addition, In the domestic fowl, the paired cranial thoracic air the kem-apoxy 151 was injected intratracheally in the sacs were situated ventral to the lungs between the other six birds (Sawad and Udah 2012)for cast sternal ribs and the heart and liver, while the paired preparations.The specimens wereleft in cold room for caudal thoracic sacs were placed more caudally about one week and then the specimens were 150 Int. J. Adv. Res. Biol. Sci. (2016). 3(8): 149-159 macerated in 3% potassium hydroxide solution for 1.2.1. Extrathoracic diverticula comprised a 48hrs, finally the air sacs were painted by different cranioventral diverticulum (figs 3, 4 & 5\3a) and acrylic colors. three lateral diverticula. The former occupied the thoracic inlet ventrally and extended between the Results clavicle and coracoid bones. On both sides, they were converged ventrally and diverged dorsally forming a In the turkey, seven thin walled and transparent air V-shaped enlargement that embraced dorsally the sacs were extended from the lungs, penetrating trachea, oesophagus, blood vessels and nerves as well between the viscera and into some bones. They as the cervical part. It aerated the coracoid bone comprised a single cervicoclavicular, paired medial (fig.7\C) as well as the clavicle (fig.7\E). The lateral clavicular, thoracic and abdominal air sacs. diverticula comprised the axillary diverticulum (fig. 1\3b) just caudal to the shoulder joint, the I. Saccus cervicoclavicularis subscapular diverticulum (fig. 1\3c) and the pectoral diverticulum (fig. 1\3d), between the The cervicoclavicular sac was a fairly large scapula and the thoracic cage, they entered between complicated air sac formed by the fusion of the the muscles of the shoulder joint and the thoracic cage.