The histology of the adrenal gland of the African elephant,Loxodonta africana

Abstract

The histology, particularly the ultrastructural cytology, of the adrenal gland of the African elephant, Loxodonta africana, is virtually unknown. Tissue from 14 adult male and female elephants was processed for light and transmission electron microscopy. The gland is surrounded by a thick capsule composed of an outer layer of dense connective tissue and an inner layer in which smooth muscle fibres predominate. Below the layer of smooth muscle, a continuous layer of relatively undifferentiated 'capsular' cells occur. Where the capsular cells abut on the zona glomerulosa, they appear to be differentiating into glomerulosa cells, as small lipid droplets are present in their cytoplasm. The cortex is divided into three zones as is found in the adrenal glands of other mammals. Large amounts of collagenous and reticular tissue support the secretory cells, which have a marked lipid content. With electron microscopy, the cortical cells show features typical of steroid-producing cells. The medulla is characterized by an outer region of pale-staining chromaffin-positive (adrenaline) cells and an inner region of intensely staining chromaffin-positive (noradrenaline) cells. The latter cells contain granules of different sizes and structure.

How should the psychological well‐being of zoo elephants be objectively investigated?

“…Long-term studies of HPA output or changes in circadian patterning seem not to have been conducted on zoo elephants; there also seems to have been no use of adrenal size/structure post mortem to assess the merits or demerits of particular husbandry systems, even though elephant adrenals have been well-studied [Kramer et al, 1991] and are typically removed during necropsies (cf. AZA standard protocols).…”

Histology of 24 organs from Asian elephant calves (Elephas maximus)

“…Organ histology records patterns of growth and provides information on the biology, evolution and physiology of life, but little is known about the histology of elephant organs. Out of all the organs in the elephant body, a few organs have been studied for their histological structure; for examples: testis ( Johnson & Buss, 1967 ; Jones & Holt, 1981 ), esophagus ( Van Aswegen et al, 1994 ), stomach ( Indu et al, 2014 ; Van Aswegen et al, 1994 ), intestine ( Van Aswegen et al, 1996 ), adrenal gland ( Kramer, Teixeira & Hattingh, 1991 ), skin ( Spearman, 1970 ), temporal gland ( Meyer, Weissengruber & Busche, 2010 ), articular cartilage ( Egger et al, 2008 ) and bone ( Curtin et al, 2012 ; Nganvongpanit et al, 2017b ). Moreover, most studies have been done on African elephants ( Curtin et al, 2012 ; Egger et al, 2008 ; Johnson & Buss, 1967 ; Jones & Holt, 1981 ; Kramer, Teixeira & Hattingh, 1991 ; Spearman, 1970 ; Van Aswegen et al, 1994 , 1996 ), while studies on Asian elephants have been limited ( Curtin et al, 2012 ; Indu et al, 2014 ; Nganvongpanit et al, 2017b ).…”

The Age Histology Adrenal Medulla of the Cattle

“…The lack of harmony between physiological state of the animal and the production technology is primarily reflected in the endocrine system. In its role as an integrating and adaptive systems, it ensures the integrity of the organism and its unity with the environment [1,4,6]. Currently, special importance has acquired a detailed study of the morphology, physiology and biochemistry of endocrine producing animals, since knowledge of the laws of the adrenal glands, as bodies directly providing the body's metabolism, is a biological basis for the development of full feeding and improving the productive qualities of farmed livestock.…”