Parasitic Gastroenteritis '" PGE (Gut Worms)
In the spring, significant numbers of overwintered larvaewill migrate onto herbage and infect lactating ewes, andif pastures are heavily contaminated, may also causespring/early summer disease in grazing lambs. Eggsdeposited by the lactating ewes and lambs will developslowly initially, but will begin to develop more quickly asthe weather warms up.
The development of strategiesto keep pasture larval contamination down to a levelthat allows acceptable lamb performance, while alsoallowing the deposition of some anthelminticsusceptibleworm eggs on the pasture to dilute anyresistant parasites present, requires veterinary input onan individual farm level.
However, if BZanthelmintics (White wormers) are to be used for treatment in outbreaksof nematodirosis, the faecal egg count of several lambsshould be checked to indicate whether significant PGE infestation is present or not.