Abstract:
A study was conducted to investigate the accumulation of trehalose in infective third (L 3 ) stage of Haemonchus
contortus induced for hypobiosis by exposure to gradual increase in temperature and decrease in moisture.
Trehalose content in stressed L 3 , hypobiotic (L 4 ) and mature H. contortus was estimated by densitometry. It was
established that infective (L 3 ) larvae subjected to moisture stress accumulated significantly (p = 0.037) higher
levels of trehalose compared to the unstressed controls. In addition, infection of goats with the stressed L 3
resulted in high proportion of larvae arrested at the fourth (L 4 ) larval stage as indicated by the number of L 4
recovered from the abomasal sub-mucosal tissue of goats slaughtered 24 days post infection. These hypobiotic
larvae (L 4 ) had significantly (p = 0.0024) higher relative trehalose content than mature H. contortus recovered
from the lumen of the abomasa. The high correlation of trehalose content in stressed larvae and hypobiosis
suggested that trehalose metabolism could play a role in hypobiosis. It is suggested that further research
should be conducted to confirm or refute this link between hypobiosis and trehalose metabolism.
