North Dakota State University * Dickinson Research Extension Center
1133 State Avenue, Dickinson, ND 58601 Voice: (701) 483-2348 FAX: (701) 483-2005

Cow-Calf Performance on Improved and Native Grass Pastures Following Worming

D. G. Landblom, J. L. Nelson, G. Myers and M. F. Andrews

Worming continued to be an important segment of research at the Dickinson Experiment Station. Several experiments have been conducted recently to evaluate the effects of performance and economic returns where worming is incorporated as a management tool. To date, with one exception, under the conditions of these studies there has been little or no performance or economic advantage for routine worming. The conditions in which we were able to measure an advantage when worming with Safe-Guard and implanting with Compudose were combined in steer calves fed backgrounding rations.

Fecal analysis has been part of each experiment dealing with worming. Analysis of intestinal worms based on fecal egg shedding has shown us that egg shedding among cows drops naturally from the time cows are turned out on spring pasture in May to a fairly stable low in the early part of July. Calves nursing these same cows, however, become infested, have lower resistance, and egg shedding among them increases to a peak in mid July to early August.

Our objective in this investigation is to study the effect that worming cows just before spring turnout and delaying calf worming until mid July has on performance and subsequent economic return to management.

Young second calf Angus X Hereford crossbred cows nursing 3/4 Angus X 1/4 Hereford crossbred calves were used to evaluate the new worming product Safe-Guard. The cows and calves grazed crested wheatgrass pastures from turnout time in May until July 24th when they weighed, calves wormed and moved to native range pastures where they remained until weaning on November 2, 1984.

The control and wormer treated groups were weighed and fecal sampled at selected intervals throughout the grazing season.

Fecal samples were analyzed at the North Dakota State University Veterinary Diagnostic Lab by Dr. Myron Andrews using the Wisconsin Double Centrifugation Sugar Flotation technique.

The animals were allotted by weight, breed, sex, sire of calf and performance index of cow based on North Dakota Beef Cattle Improvement Association performance indexing.

Gains and partial economic results of this investigation have been summarized in Table 1.

Summary: Worming of cows with Safe-Guard resulted in slightly better daily gains for the entire grazing season. There was no advantage for mid July worming of calves even through the eggs per gram of feces being shed was reduced to very low levels.

Based on these results there is no doubt that Safe-Guard is an effective, easy to use product, but the level of parasitism that prevailed under the conditions of this investigation was not great enough to depress animal performance. No economic advantage was realized.

Table 1. Weights, gains and worming costs for cows and calves wormed with Safe-Guard
  Wormed Control
Cows   Calves Cows   Calves
No. head 34   34 34   34
Days on pasture (May 24-Nov 2, 1984)   162     162  
Initial wt., lbs. 969   160 950   163
Final wt., lbs. 1109   474 1062   492
Avg. gain/hd., lbs. 140   314 112   329
ADG, lbs. 086   1.94 .69   2.03
Wormer cost/cow, $ (22ml of 10% Suspension) 2.64     ---    
Wormer cost/calf, $ (7.5ml of 10% Suspension)     .89     ---
Total investment/cow-calf pair, $   3.53        

Back to 1985 Research Reports Table of Contents
Back to Research Reports
Back to Dickinson Research Extension Center