국내육계농장의 닭콕시듐 원충 오염 및 분리원충의 약제감수성

Contamination and drug sensitivity of field isolates of coccidia from broiler farms

Litter samples collected from broiler farms in domestic area from June to November 1985 were investigated for contamination of avian coccidia and the isolates of coccidia from the litters were tested for their resistance to anticoccidial drugs. Of 556 farms investigated, 66.9% was contaminated with coccidia. Percent of farms with light(EPG＜10,000), moderate (10,000≤EPG＜50,000) and heavy (EPG≤50,000) contamination were 50.9%, 10.6% and 5.4%, respectively. Incidences of the contamination by provincial area were highest in Kyeungbuk (74%) followed by Jeunnam(72.3%), Chungnam(62.5%) and Kyeunggi(57.4%) in decreased order. Seasonal incidences of the contamination were highest in September(80.2%) and lowest in June(63.1%) and November(58.0%). The motalities of Nicarbazin, and Stenorol medicated groups(average 0-5%)were significantly lower than those of Salinomycin, and Lasalocid medicated groups(average 8.1-8.8%). Based upon anticoccidial index(ACT), the sum of percent reduction of relative weight gain and percent reduction of lesion score, ACI scores of medicated groups (average 123.0-192.3) were significantly higher than those of infected-nonmedicated group. Of medicated groups, ACI score of Nicarbazin(192.3) was significantly higher than those of the other groups including Stenorol(134.6), Lasalocid(131.5), and Salinomycin(123.0). All 16 isolates of coccidia tested were sensitive to Nicarbazin while 25% of them were sensitive to Salinomycin, 37.5% to Lasalocid, and 43.7% to Stenorol. All isolates except one(93.7%) were resistant to one or more drugs tested.