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1.
Peek HW  Landman WJ 《Avian diseases》2006,50(3):434-439
Twenty European Eimeria spp. field isolates were subjected to an anticoccidial sensitivity test (AST). The anticoccidial drugs tested were diclazuril (Clinacox) and monensin (Elancoban). The assay was performed in a battery cage trial. Infected medicated birds were compared with an unmedicated control group. Coccidial lesion scores and oocyst shedding were used as parameters. The results of the AST show that resistance is common amongst coccidiosis field isolates, especially Eimeria acervulina (68% and 53% resistance for diclazuril and monensin, respectively). Resistance is less frequent amongst Eimeria maxima (38% and 50% resistance for diclazuril and monensin, respectively) and Eimeria tenella isolates (23% and 38% resistance for diclazuril and monensin, respectively). A highly significant influence of the coccidiosis prevention program (live coccidiosis vaccination with Paracox-5 vs. anticoccidial drugs in feed) on the sensitivity patterns of Eimeria spp. field isolates for both diclazuril (P= 0.000) and monensin (P= 0.001) was found. Further, when looking at the single species and each anticoccidial drug level, significantly more sensitivity of E. acervulina for monensin (P= 0.018), E. maxima for diclazuril (P = 0.009), and E. tenella for diclazuril (P = 0.007) was found in isolates originating from vaccinated flocks. Moreover, for E. acervulina and diclazuril, E. maxima and monensin, and E. tenella and monensin a trend toward higher sensitivity of isolates for these products was found when live coccidiosis vaccination was applied. The present study shows that sensitivity for the anticoccidial drugs diclazuril and monensin is more frequent in Eimeria spp. field isolates originating from broiler farms where a coccidiosis vaccination policy is followed.  相似文献   

2.
Coccidia were isolated from 90 broiler farms in 15 poultry-producing areas in Brazil and Argentina. Sixty isolates were tested for sensitivity to 7 anticoccidial drugs. The common species were: a) Eimeria tenella, 47 isolates; b) E. maxima, 49 isolates; c) E. acervulina, 44 isolates; d) E. mitis, 26 isolates; and e) E. brunetti, 12 isolates. Isolates were considered sensitive to drugs if intestinal lesion scores of medicated broilers were reduced by at least 50% compared with unmedicated infected broilers or if weight gain was at least 75% of that of uninfected birds in a 6-day laboratory test. According to lesion scores, there was evidence of resistance or seriously reduced sensitivity to monensin in 20 isolates, narasin in 29, salinomycin in 11, maduramicin in 1, clopidol in 36, amprolium in 40, and nicarbazin in 1. According to broiler weight gain, there was resistance to monensin in 36 isolates, narasin in 32, salinomycin in 28, maduramicin in 2, clopidol in 28, amprolium in 50, and nicarbazin in 4. These results suggested incomplete cross resistance of coccidia to polyether ionophorous drugs. The degree of resistance might be explained by previous patterns of use of these drugs.  相似文献   

3.
Drug-sensitivity of 99 isolates of coccidia from broiler farms   总被引:7,自引:0,他引:7  
Coccidia were isolated from 99 broiler farms in 12 broiler-producing states and tested for sensitivity to contemporary anticoccidial drugs. The isolates usually comprised two or more species, including 92 Eimeria acervulina, 47 E. maxima, 28 E. tenella, and 10 E. brunetti. Based on intestinal-lesion-score reduction of 30% or more, 38% of isolates were resistant to monensin (110 ppm), 29% to salinomycin (60 ppm), 20% to nicarbazin (125 ppm), and 46% to amprolium + ethopabate (125 + 4 ppm). Isolates with 50% or greater reduction of lesion scores were considered sensitive. Thirty-three percent were sensitive to monensin, 53% to salinomycin, 67% to nicarbazin, and 39% to amprolium + ethopabate. Other isolates had intermediate response to drugs and were considered to have "reduced sensitivity." There was some evidence for incomplete cross resistance to the polyether, ionophorous products.  相似文献   

4.
Anticoccidial vaccine and an anticoccidial drug rotation program were compared to determine which program was more effective in producing coccidia populations sensitive of 1 ppm diclazuril. The study used an anticoccidial drug-sensitivity battery test (AST) to determine the baseline level of diclazuril sensitivity to field isolates of Eimeria spp. from seven broiler complexes that had used diclazuril. Based on percentage reduction in weight gain and lesion scores, 25% or fewer of the isolates were effectively controlled by diclazuril. Following the baseline sampling, four of the complexes switched to a nondiclazuril in-feed anticoccidial drug program and three of the complexes switched to a vaccination program for two broiler grow-out cycles as the sole coccidiosis-control program. This study demonstrated that the vaccine used (Coccivac-B) contained anticoccidial drug-sensitive strains. Eimeria isolates were subsequently collected from the identical houses and diclazuril AST results were compared with the baseline AST results. Following the two grow-out cycles, sensitivity of the isolates to diclazuril from the four complexes that continued to use in-feed anticoccidial drugs remained essentially unchanged. The isolates from the three complexes that switched to the vaccination program demonstrated a marked increase in diclazuril sensitivity, with 60%-100% of the isolates from each complex effectively controlled by diclazuril. Vaccination with the anticoccidial drug-sensitive strains produced a measurable increase in the level of sensitivity to diclazuril.  相似文献   

5.
目的为检测柔嫩艾美耳球虫秦皇岛株和唐山株株对氯羟吡啶、氨丙啉、马杜霉素、地克珠利和尼卡巴嗪等5种抗球虫药的抗药性。方法选择280只14日龄雏鸡,随机分成14组,其中每株球虫均设5个感染用药组,1个感染不用药组,1个不感染不用药组,每组20只,以POAA、RLS、ROP、ACI作为指标。结果秦皇岛株对所选的5种抗球虫药物均产生不同程度的抗药性,而唐山株对氯羟吡啶、马杜霉素和地克珠利有不同程度的抗药性,对氨丙啉和尼卡巴嗪无抗药性。其中在这5种抗球虫药物中,秦皇岛株和唐山株柔嫩艾美耳球虫对地克珠利均呈现完全抗药性。结论目前地克珠利在秦皇岛和唐山两地区须减少或暂停使用。  相似文献   

6.
为检测巨型艾美耳球虫和柔嫩艾美耳球虫早熟株对常用抗球虫药的敏感性,选用地克珠利、氯苯胍、二硝托胺、癸氧喹酯、尼卡巴嗪、马杜米星、盐霉素和拉沙洛西等8种抗球虫药进行鸡体试验,通过抗球虫活性百分比(percent of optimum anticoccidial aetivity,POAA)、病变记分减少率(reduction of lesion scores,RLS)、相对卵囊产量(relative oocyst production,ROP)和抗球虫指数(anticoccidial index,ACI)4项指标进行综合评价。结果表明,巨型艾美耳球虫早熟株对8种药物敏感;柔嫩艾美耳球虫早熟株对盐霉素轻度敏感,对地克珠利、氯苯胍、二硝托胺、癸氧喹酯、尼卡巴嗪、马杜米星和拉沙洛西敏感。本研究结果可为对球虫早熟株疫苗的开发与应用提供实验依据。  相似文献   

7.
用鸡体实验法,以相对卵囊产量(ROP)、病变记分减少率(RLS)、最适抗球虫百分数(POAA)和抗球虫指数(ACI)等4项指标,分析了一株毒害艾美耳球虫对复方磺胺氯吡嗪钠(20%磺胺氯吡嗪钠+4%二甲氧苄啶)、血痢宁(磺胺氯吡嗪钠可溶性粉)、贝尔球康(又称鸡球虫散,含青蒿、仙鹤草、何首乌、白头翁、肉桂等)、百球清(妥曲珠利)、马杜球败(马度米星铵预混剂)等5种抗球虫药的耐药性.结果显示:该株毒害艾美耳球虫对百球清无耐药性,对复方磺胺氯吡嗪钠和血痢宁有轻度耐药性,对贝尔球康无耐药性或轻度耐药性,对马杜球败有完全耐药性.提示该养殖场应停止使用马杜拉霉素,改用妥曲珠利或贝尔球康,但必须进行轮换用药或联合用药,以延长药物的使用寿命.  相似文献   

8.
上海地区鸡球虫对6种抗球虫药的抗药程度研究   总被引:36,自引:5,他引:36  
为了解上海地区的鸡球虫抗药性状况,作者采集了上海市9个区县10个鸡场的球虫,进行了对地克珠利(Diclazuril)、氯苯胍(Robenidine)、氯羟吡啶(Clopidol)、氨丙啉(Amprolium)、马杜拉霉素(Maduramicin)、莫能霉素(Monensin)的抗药性研究。试验设6个药物组和感染不用药、不感染不用药2个对照组,以抗球虫指数(ACI)、病变记分减少率(RLS)、相对卵囊产量(ROP)、最适抗球虫活性百分率(POAA)为试验指标,进行综合评定,其抗药程度分为无抗药性、轻度抗药性、中度抗药性、完全抗药性4个等级。结果显示来自10个鸡场的球虫中,对地克珠利有90%未产生抗药性,对氯苯胍有90%为无抗药性和轻度抗药,对驻杜拉霉素有50%为无抗药性和轻度抗药,对氯羟吡啶有80%达到完全抗药,对氨丙啉有90%达到中度和完全抗药,对莫能霉素则全部达到中度以上的抗药程度,作者认为目前在上海地区以放心地理合理使用地克珠利和氯苯胍,对马杜拉霉素要慎使用,对氯羟吡啶、氨丙啉、莫能霉素须减少或暂停使用。  相似文献   

9.
柔嫩艾美耳球虫扬州分离株对8种抗球虫药的抗药性   总被引:6,自引:2,他引:4  
将柔嫩艾美耳球虫(Eimeria tenella)扬州分离株感染14日龄苏禽黄羽肉鸡,设立8个用药组、1个感染不用药对照组和1个不感染不用药对照组,以相对卵囊产量、病变记分减少率、最适抗球虫百分数和抗球虫指数为指标对该虫株对盐霉素、马杜拉霉素、球痢灵、氯羟吡啶、氨丙啉、尼卡巴嗪、甲基三嗪酮、地克珠利等8种常用抗球虫药的抗药性进行了综合评定,分析了该地区球虫的抗药性及对策。结果表明,该虫株对甲基三嗪酮敏感,对氨丙啉具有中度抗药性,对盐霉素、马杜拉霉素、球痢灵、氯羟吡啶、尼卡巴嗪、地克珠利等其他6种药物具有完全抗药性。提示目前在扬州地区甲基三嗪酮抗球虫疗效最好,氨丙琳效果稍差,应合理使用,盐霉素等其他6种药物应慎用、减少或暂停使用。  相似文献   

10.
Out of six isolates of coccidia of the species Eimeria tenella, obtained in the years 1984 and 1985 on farms with a stationary occurrence of coccidiosis, five were found to have reduced sensitivity or resistance to monensin. Neither were these isolates sensitive to further monovalent ionophorous anticoccidials narasin and salinomycin. The bivalent ionophorous anticoccidial lasalocid controlled five isolates completely, but for one its effectiveness was reduced. An isolate obtained on a farm with long-term absence of coccidiosis was sensitive to all anticoccidial drugs.  相似文献   

11.
The anticoccidial efficacy of diclazuril, a novel anticoccidial agent, was titrated in laboratory experiments using recent field isolates of Eimeria. Fifty tests were conducted with six individual species isolates, and seven tests were done with a mixture of the six species. Results were based on intestinal lesion scores at necropsy, droppings scores, and weight gain. Diclazuril at 0.5 ppm was almost completely effective against E. tenella, E. acervulina, and E. mitis. Prevention of E. brunetti was better at 1.0 ppm than at 0.5 ppm. In birds infected with E. mitis. Prevention of E. brunetti was better at 1.0 ppm than at 0.5 ppm. In birds infected with E. maxima, diclazuril at 0.5-1.5 ppm significantly reduced lesion scores and droppings scores and improved weight gain, although lesions were higher than with other species. Oocyst shedding by E. maxima was almost completely prevented by 0.5-1.5 ppm. Lesion scores and droppings scores caused by E. necatrix or mixed infections were greatly reduced by 0.5 ppm of diclazuril, but 1.0 ppm was necessary to obtain full protection of weight gain. Results suggest that 1.0 ppm of diclazuril best prevents coccidiosis caused by six species of coccidia in chickens.  相似文献   

12.
Thirty isolates of Eimeria tenella obtained from broiler and breeder farms were examined for their sensitivity to anticoccidial drugs. All were sensitive to robenidine, 28 were sensitive to methyl benzoquate, 25 to clopidol and 21 to nicarbazin. Most isolates were resistant or partly resistant to amprolium and dinitolmide.  相似文献   

13.
为掌握鸡场球虫抗药程度,以便制定合理用药方案,采集福建省莆田市某鸡场盲肠球虫,进行柔嫩艾美耳球虫单卵囊分离和纯化;采用鸡体试验法,设立5个用药组、1个感染不用药对照组和1个不感染不用药对照组,以病变记分减少率(Reduction of lesion sores,RLS)、抗球虫指数(Anticoccidial index,ACI)、相对盲肠卵囊产量(Relative at oocyst production,ROP)和最适抗球虫活性百分率(Percent of optimum anticoccidial activity,POAA)4项为指标,检测该球虫对癸氧喹酯、尼卡巴嗪、地克珠利、二硝托胺和氯苯胍等5种常用抗球虫药的抗药性。结果表明:该虫株对癸氧喹酯敏感,对地克珠利、二硝托胺和氯苯胍具有完全抗药性,对尼卡巴嗪为中度抗药性,说明目前莆田市球虫抗药性非常严重,癸氧喹酯可用于抗球虫病,其他药物应慎用或暂停使用。  相似文献   

14.
Isolates of Eimeria species obtained from broiler or from breeder farms were compared for their sensitivity to two ionophorous anticoccidial drugs, monensin and lasalocid. All of 25 isolates from broiler farms were resistant to 100 ppm monensin or 90 ppm lasalocid, while 14 of 16 isolates were resistant to monensin and seven of 16 to lasalocid from breeder farms (replacement layer and broiler breeder).  相似文献   

15.
柔嫩艾美球虫常州株对5种抗球虫药的抗药性分析   总被引:2,自引:1,他引:1  
将柔嫩艾美耳球虫(E.tenella)常州分离株感染14日龄苏禽黄羽肉鸡,设立5个用药组、1个感染不用药对照组和1个不感染不用药对照组,以相对卵囊产量、病变记分减少率、最适抗球虫百分数和抗球虫指数为指标对该虫株对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪、癸氧喹酯5种常用抗球虫药的抗药性进行了综合评定,分析了该地区球虫的抗药性及用药对策。结果表明,该虫株对癸氧喹酯敏感,对球虫宁、地克珠利、马杜霉素、磺胺氯吡嗪具有完全抗药性,提示目前常州地区球虫抗药性非常严重,癸氧喹酯抗球虫疗效最好,其他药物应合理使用、应慎用、减少或暂停使用。  相似文献   

16.
A method previously described by Jeffers and Bentley, involving calculation of a growth and survival ratio and optimal anticoccidial activity index, was used to investigate the sensitivity of 23 field isolates of Eimeria obtained from turkey flocks to the ionophorous antibiotic monensin. Isolates were obtained from litter and intestinal samples from several major turkey-growing regions of the United States, and in most cases contained at least two species of Eimeria. A mixture of strains that had been maintained in the laboratory for many years in the absence of exposure to anticoccidial drugs was found to be sensitive to monensin. Six of the field isolates were judged sensitive, seven partially resistant, and ten resistant to the drug, judged by the Jeffers and Bentley criteria. This is the first report of the acquisition of resistance to monensin in isolates of Eimeria from turkey flocks in the United States.  相似文献   

17.
雏鸡分组后人工感染果洛地区柔嫩艾美耳球虫分离株2.4×105个/只,分别采用地克珠利、氨丙啉、尼卡巴嗪、磺胺氯吡嗪钠、复方磺胺对甲氧嘧啶等5种常用抗球虫药进行治疗观察,以POAA、RLS、ROP、ACI作为评定指标.结果表明,柔嫩艾美耳球虫果洛分离株对氨丙啉、地克珠利高度敏感,对尼卡巴嗪、磺胺氯吡嗪钠均产生不同程度的耐...  相似文献   

18.
柔嫩艾美耳球虫早熟耐药株对几种抗球虫药的敏感性   总被引:2,自引:0,他引:2  
为了探讨鸡柔嫩艾美耳球虫早熟耐药株对常用抗球虫药的敏感性,采用尼卡巴嗪、氯苯胍、球痢灵、地克珠利和常山酮5种抗球虫药,对由晋球1号球虫疫苗虫株复制的病鸡进行防治试验,通过相对卵囊产量(ROP)、相对增重率、抗球虫指数(ACI)、病变记分减少率(RLS)和最适抗球虫活性百分率(POAA)5项指标进行综合评定.结果表明,柔嫩艾美耳球虫早熟耐药株对盐酸氯苯胍无抗药性,对地克珠利有轻度抗药性,对常山酮、球痢灵、尼卡巴嗪有部分抗药性,它们的抗球虫指数为187.46~246.75,达到了抗球虫效果.  相似文献   

19.
以最适抗球虫活性百分率(POAA)、病变记分减少率(RLS)、相对卵囊产量(ROP)和抗球虫指数(ACI)为指标,检测了尼卡巴嗪对秦皇岛株和唐山株柔嫩艾美耳球虫的敏感性.结果表明,唐山株柔嫩艾美耳球虫对尼卡巴嗪无耐药性,秦皇岛株对其呈轻度耐药性.提示尼卡巴嗪在唐山和秦皇岛地区可以继续合理使用,但应控制用量和使用时间,以...  相似文献   

20.
柔嫩艾美耳球虫YL株抗药性研究   总被引:4,自引:0,他引:4  
用柔嫩艾美耳球虫杨凌株 ( YL t)对 1 4日龄雏鸡进行感染 ,检测了该虫株对 4种常用抗球虫药 (马杜拉霉素、地克珠利、克球粉和氯苯胍 )的敏感性。以最适抗球虫活性百分率、抗球虫指数、相对卵囊产量和病变记分减少率为指标 ,进行综合评定 ,其抗药程度分为无抗药性、轻度抗药性、中度抗药性和完全抗药性 4个等级。结果表明 ,该虫株对马杜拉霉素有轻度抗药性 ,对地克株利有完全抗药性 ,对克球粉和氯苯胍无抗药性。  相似文献   

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