Anatomical and histological study of the kidneys and salt glands in great flamingos (Phoenicopterus roseus)

Abstract

<jats:p> This study was designed to explain the anatomy and histology of kidneys and salt glands in Great Flamingos. Eight adult healthy Great Flamingos of both sexes have been used. The results showed that the kidneys in Great Flamingos consist of three separated lobes. The right kidney was longer 8.9±0.3 mm than the left kidney 8.4±0.4mm. The ratio of the kidneys weight to the total body weight was 0.39%. The salt gland was very large crescent shape, and occupied the supraorbital fossa and has 20.8±0.2mm long and 3.9±0.2mm in diameter. The volume of cortex was 60-70% and the medulla was 30-40%. Within the middle region of cortex there were numerous large corpuscles (mammalian type) and few of small corpuscles (reptilian type). There was a variation between the means diameters of mammalian type 59±1µm and reptilian type 42±0.9µm. The proximal and distal convoluted tubules and collecting ducts were lined by simple cuboidal epithelium and their means diameters were 46±0.9, 44±1 and 55.1±0.7µm, respectively. Within medulla the thick and thin segments were arranged at the peripheral zone of medullary cone while the collecting ducts were at the central part of cone and all were lined with simple cuboidal epithelium except thin segments were lined with squamous cells. The salt gland were consisted of lobules surrounded by thick connective tissue capsule and each has mass of branched tubuloacinar secretory unites. The latter were made up by single layer of cuboidal cells. The tubules lead into central duct lined by double layer of cuboidal cells while the main duct lined with stratified cuboidal epithelium. The secretory units of salt gland gave negative reaction to PAS and combined AB (pH 2.5) and PAS stains and this indicate the absence of neutral mucosubstances. The results concluded that the kidneys in great flamingo was small size organ with low relative weight in compare to birds size and the salt glands was active organ.</jats:p>

Morphometrical and Histological Changes in Domestic Duck Salt Glands in Response to Salinated Water

“…The secretary tubules are lining with a single layer of principal cuboidal cells forming a narrow lumen , the peripheral blind end of the tubules are lined round peripheral cells. This histological observed of the salt glands are in agreement with the results of many workers whom studied the histological structures of salt gland in many water birds species such as Hussein et al (2006), Jarrar (2009), Mohammad (2012), Reshag et al (2016) and Waleed (2016). They showed that the salt gland in different avian species is consists of several longitudinal lobules composed of secretary tubules radiating from central canals.…”

“…The gross or anatomical feature of the salt gland in both experiment group birds, which includes the crescent shape and supraorbital location were as the same as what was mention in all most all water birds such as (ducks, geese, common coot, moor hen, and flamingo) which was studied by (Maysoon, 2012;Hussein et al, 2006;Al-Mansour, 2014;Reshag et al, 2016). with some exception, the shape of salt gland in Kentish plovers and love birds was tubular in shape as mentioned by (Jarrar, 2009;Waleed, 2016).…”

“…This changes proved the results of Martin and Philpot (1973);Burgerand Gochfeld (1984). Muller and Hildebrandt (2003) and Reshag et al (2016) found that the histological changes in the salt glands as response to salinity were blood vessels congestion hyperplasia, proliferation and differentiation in different subsets of cells. induces due to adaptive strategy of water birds.…”

“…The salt glands (nasal gland) are very important adaptive tool in many animals species which live in oscine, salty lacks and aired land such as water birds, snakes and crocodile (Sabat, 2000;El-Gohary, 2009;Babonis et al, 2011;Cramp et al, 2008). The salt gland have been reported in many different avian orders (Spheniciformes, Precelariformes, Charadriformes, Pelecaniformes, Anseriformes, Phoenicopteriformes) (Jarrar, 2009;El-Gohary et al, 2013;Maysoon, 2012;Reshag et al, 2016). Since the avian kidneys are not sufficient in excreting salt and electrolytes to control body fluid homeostasis (Holmes and Phillips, 1985).…”

An investigation on the renal portal system in long-legged buzzard (Buteo rufinus)

“…The renal portal system in avian, which is different from mammals, allows the excretion of uric acid by tubular secretion (10,13,17). The vessels in this system may differ between species (5,8,12).…”