Technical Abstract: Widespread anthelmintic resistance in small ruminants has necessitated alternative means of gastrointestinal nematode (GIN) control. The objective was to determine the effectiveness of copper oxide wire particles (COWP) administered as a gelatin capsule or in a feed supplement to control GIN in goats. In four separate experiments, peri-parturient does (n = 36), yearling does (n = 25), weaned kids (n = 72), and yearling bucks (n = 16) were randomly assigned to remain untreated or administered 2 g COWP in a capsule (in Experiments 1, 2, and 3) or feed supplement (all Experiments). A pooled fecal sample collected for culture on Day 0 (day of COWP administration) from the yearling and peri-parturient does indicated that Haemonchus contortus comprised 72% and 61% of nematode population, respectively; the remaining nematodes were mainly Trichostrongylus spp. Pooled fecal samples collected weekly from kids indicated 58% H. contortus on Day 0 reaching a low of 0% in COWP-treated kids on Day 21 compared with 36% in untreated kids. Feces and blood were collected every 7 d between Days 0 and 21 (older goats) or Day 42 (kids) for fecal egg counts (FEC) and blood packed cell volume (PCV) analyses. The FEC were log transformed for data analysis. A peri-parturient rise in FEC was evident in the untreated does, but not the COWP-treated does (COWP × date, P < 0.02). In yearling does, FEC of the COWP treated does tended to be lower than the untreated (COWP, P < 0.02). FEC of COWP-treated kids were reduced compared with untreated kids (COWP × date, P < 0.001). FEC of treated and untreated bucks was similar, but H. contortus was not the predominant nematode in these goats. However, total worms were reduced in COWP-fed bucks (P < 0.03). In summary, it appeared that COWP in the feed was as effective as COWP in a gelatin capsule to reduce FEC in goats. COWP administration may have a limited effect where H. contortus is not the predominant nematode.