The regulation of populations of Ostertagia ostertagi in calves

摘要: The course of the worm burdens calves infected daily with larvae Ostertagia ostertagi at five different rates was studied by making post-mortem counts on groups killed after experiencing infection for periods time.The relationship between numbers and together evidence that a turnover worms occurred, led to conclusion adult were regulated primarily loss rate proportional number present.Further, estimates based developing fourth-stage indicated proportion administered which became established decreased gradually as experiment progressed.At very low rates, slower than high but in all it remained constant through 6 months duration experiment.The development small arrested early fourth stage. At highest used, inhibited somewhat greater.