Studies on the development of omasum in west african dwarf goats (Capra hircus)

Abstract

This work studied the sequential morphological changes of omasum in foetuses, neonates and adult West African Dwarf (WAD) goats by gross and light microscopic methods. The mean omasal volume was 1.37 +/- 0.36, 4.2 +/- 0.4, 8.7 +/- 6.9 and 60.1 +/- 8.6 ml for gestation day 87 and 146 foetuses, neonates and adults respectively. Grossly the mucosa exhibited longitudinally oriented primary, secondary, tertiary and quartnery laminae with smooth surface in foetuses and numerous papillae in the adults. Microscopically it was lined by stratified squamous epithelium which was divided into larger lighter luminal and smaller darker basal zones in gestation day 60 foetuses. The core of the laminae contained extension of the inner muscular tunic. The basal zone developed lateral evaginations (corial papillae) into the lighter zone of the laminae in gestation day 106 foetuses. By term these corial papillae approached the luminal surface. The papillae emerged above the luminal surface in 4 week old neonates. The papillae were fully developed in adult goats. The mean papillary height and width were -205.1 +/- 34.0, 67.0 +/- 9.6; 235.0 +/- 86.5, 185.0 +/- 42.3 and 570.3 +/- 60.0, 290.1 +/- 66.3 microm for foetuses, neonates and adult goats. The inner circular layer was thicker than the outer longitudinal layer of the muscular tunic. The central muscular layer of the laminae originated from the inner circular layer with attachment to the outer muscular layer in adults. This attachment could be adaptation for better anchorage and muscular contraction of the laminae in WAD goats.

Gestational variations in the macro anatomy of the fore stomach of goat (Capra hircus)

“…Tertiary and quarterly laminae were first observed by 55 and 87 days of gestation, respectively and were eight and twenty four in number, respectively. Present observations were in partial agreement with the findings of Nwaogu and Ezeasor, (2008) in West African dwarf goats. These authors observed only first three type laminae by mid gestation while quarterly laminae by full term.…”

“…8). In contrast to this Nwaogu and Ezeasor (2008) noticed smooth omasal laminae in the fetuses and numerous papillae in adult West African dwarf goats. Dellmann and Brown (1987) mentioned that largest omasal laminae had a thick concave free edge.…”

Morphological Features Of Fetal And Adult Adrenal Glands In Kano Brown Goats (Capra hircus)

“…Twenty-one fetal and twenty-one adult adrenal glands used for this study were collected from slaughtered Kano brown goats in Nsukka and Obollo-Affor abattoirs. The age of the fetuses was determined by crown-rump length method (Nwaogu and Ezeasor, 2008). The age of the adult goats was estimated using dentition (Chibuzo, 2006).…”

Understanding the role of rumen epithelial host-microbe interactions in cattle feed efficiency

“…(1978) reported that the rumen tissue of a 90-day bovine fetal was already distinguished into mucosa, muscularis, and serosa with a stratified-cubodial epithelium including 2 different epithelial layers (basal and superficial; 10 cell layers) before birth. Postnatally, the rumen epithelium of neonatal ruminants (30 d after birth) had lower cell layers (6 cell layers) and more differentiated structure, a stratified squamous epithelium ( Arias et al., 1978 ; Nwaogu and Ezeasor, 2008 ). Increased intake of solid feed particles during early life stimulates the increased rumen mass, papillary growth, and keratinization.…”