Efficacy of a topical formulation of ivermectin against naturally acquired gastro-intestinal nematodes in weaner cattle

The efficacy of a topical formulation of ivermectin against naturally acquired gastro-intestinal nematodes in weaner cattle was evaluated. At slaughter, 14-15 days after treatment, burdens of Ostertagia spp, Trichostrongylus axei and Oesophagostomum radiatum were significantly lower in the treated calves than in the untreated controls (p<0.01). Efficacies (based on geometric mean worm burdens of treated and control groups) were 99.6%, 95.1% and 100% respectively. The sizes of the Cooperia spp and Trichuris ovis burdens in the treated group did not differ significantly at the 5% level of confidence from those in the control group.     

Boar culling in swine breeding herds in Minnesota

This investigation was conducted to study boar culling patterns in swine breeding herds. Data were obtained from 84 swine breeding herds and included 440 boars that were culled. Each producer was involved for 12 consecutive months, and recorded every boar that was removed from the herd, the date, and the reason for culling. The annual culling rate for the 84 farms averaged 59.4% ± 6.4 (SEM). The correlation coefficient between boar and sow culling was 0.52 (p <0.0001). Removal was the result of being overweight (47%), reproductive problems (18%), leg problems (12%), death (7%), and other diseases (4%). From the annual culling rate, the average breeding life of boars was estimated at 20 months. From this study, we concluded that the annual culling rate for boars in commercial herds was high and related to several different factors.