Internal Parasitism of Beef Yearlings as Affected by Type of Pasture, Supplemental Corn Feeding, and Age of Calf

Abstract

The following general conclusions may be drawn from the data herein reported: Calves on fescue pastures had heavier worm loads at autopsy, or showed more harmful effects of parasitism, than similar calves on temporary winter or crimson clover pastures. This was due, at least partly, to a lower nutritive value of the fescue grass. Conversely, the high nutritional quality of temporary and crimson clover forages appeared be a factor in checking the harmful effect of large numbers of parasites which were sometimes acquired on these pastures. Calves on each type of pasture that received corn supplement generally had fewer worms than those on the same types of pasture without corn supplement. Spring-dropped, and, therefore younger calves, as a group, had from two to three times as many worms as the fall-dropped or so-called early calves. A difference of only two months in time of dropping of calves resulted apparently in a considerable difference in the degree of parasitism.