Abstract:
Proc. Aust. Soc. Anim. Prod. I996 Vol. 21 PROTECTED PROTEIN REDUCES THE FAECAL EGG COUNT OF WEANERS EXPOSED TO GASTROINTESTINAL PARASITES R.M. SMITHA, J.E. HOCKING EDWARDSA and R.A. DYNES B * Faculty of Agriculture, Animal Science, University of Western Australia, Nedlands, W.A. 6907 * CSIRO Division of Animal Production, Private Bag, PO Wembley, W.A. 6014 Growing lambs infected with gastrointestinal parasites are in a state of induced protein deficiency at a time of maximum growth potential and when an effective immune response is required (Bown et al. 199 1). The present experiment investigated the effect of supplementation with protected protein on the development of immunity in growing lambs. Sixteen 12-week old Merino wethers were stratified by liveweight and randomly allocated to 1 of 2 groups (mean liveweight 17.6a.38 kg; n=8). All sheep received 5000 Trichostrongylus colubriformis and 3000 Ostertagia circumcincta infective larvae per week (week 1-12). From week 5, both groups received oaten chaff; in addition, the canola group received 33% canola meal pellets (65% canola meal, 24% lupins, 10% oats and 1% Ca(OH)z; 57% protection) and the lupin group received 30% lupins (35% protection; Hume 1974) (week 5- 12). The two diets were isonitrogenous. Faecal egg counts (FEC) were monitored weekly, commencing week 3. Peak FEC did not differ between groups but declined more rapidly in the lambs being fed protected protein than the lupin fed group (Figure 1.). The lupin group produced significantly more eggs than the canola meal group at the termination of the experiment (week 12; PcO.05); this difference tended towards significance from week 9 (PcO. 10). The rapid decline in FEC in the canola meal fed animals may indicate earlier or enhanced development of immunity. . Parasitol. 56: 163-80. 386