ABSTRACT
Sea lice data collected from Atlantic salmon farms in the Broughton Archipelago between 2003 and 2005 were examined for inter-regional differences in mobile Lepeophtheirus salmonis (Krøyer) abundance using the generalized linear model procedure. Factors such as age of the salmon populations, location of farms and time of year had a significant effect on the abundance of the mobile stages of L. salmonis whereas water temperature and salinity did not. Separate evaluation of SLICE treatment data found no significant difference in treatment frequency among the areas but did show that there were significantly lower numbers of farm treatments during the summer months when compared with other seasons. The role of environment and wild fish in influencing sea lice abundance on the farmed salmon is discussed. The findings suggest that effective management programmes for sea lice should not only be based on geographical location but should take into account other factors which could influence lice abundance levels.
Subject(s)
Copepoda/physiology , Fish Diseases/parasitology , Salmo salar/parasitology , Animals , British Columbia/epidemiology , Ecosystem , Fish Diseases/epidemiology , Fisheries , Geography , Linear Models , Population DensityABSTRACT
Autoradiography of sections from the brains of anesthetized rats injected with [14C] 2-doexyglucose revealed neural systems unilaterally activated by rewarding electrical stimulation of the medial forebrain bundle. Since this new technique marks neural systems on the basis of their activity, it has great potential in functional neuroanatomy. The potential is easily realized in brain-stimulation studies, where systems may be driven to exceptionally high levels of activity.
