Biometrical and histological studies on blood-air barrier of gaddi goats and sheep of Himalayan region

A study was designed to find out any significant difference in the morphology of gas exchange chamber of lungs in Gaddi goats and sheep that migrate every year for low hills to higher pastures of Himalayas. Lung samples were collected from 17 Gaddi goats and 20 sheep for histo-architecture and histo chemistry. The average size of alveolar duct in Gaddi goats and sheep was 219.78±8.51 and 141.00±7.86 μm, respectively. The average height of pneumocyte-I cells in Gaddi goats and sheep was 4.97±0.99 and 4.02±0.13 μm, respectively. The average thickness of the blood air barrier in Gaddi goats and sheep was 9.90±1.40 and 8.04±0.15 μm, respectively. The study suggests that Gaddi sheep has thinner barrier for oxygen permeability in the lungs than Gaddi goats. This may help them to thrive better at higher mean sea levels, where atmospheric oxygen concentrations are low.