首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 62 毫秒
1.
The anticoccidial efficacy of diclazuril was studied in rabbits artificially infected with Eimeria flavescens, Eimeria intestinalis, Eimeria magna and Eimeria perforans. Continuous administration at 1 and 2 ppm in pelleted feed proved to be highly efficacious in controlling oocyst output and faecal scores. The weight gain was comparable and the feed efficiency slightly improved compared with the non-infected, non-medicated controls, and clinical signs were fully prevented. Medication of rabbits at 0.5 ppm also provided a significant improvement in all parameters compared with the infected, non-medicated controls. In order to obtain 100% effectiveness in the control of intestinal coccidiosis in rabbits, continuous medication at 1 ppm is recommended.  相似文献   

2.
几种药物对兔球虫病的疗效试验   总被引:5,自引:0,他引:5  
选用40只45日龄左右、严重自然感染兔球虫的日本大耳白兔,随机分成5组,即兔球灵组(1500mg/kg)、地克珠利组(2mg/kg)、拉沙洛菌素组(150mg/kg)、氯苯胍组(300mg/kg)、不给药对照组,分别将药物按一定比例混匀在饲料中,制成颗粒料让兔自由采食,以比较其对兔球虫病的治疗效果.通过临床观察,分析每克粪便卵囊数的变化,记录增重,计算饲料转化率并对每组兔剖杀作剖解观察.结果表明:兔球灵、地克珠利和拉沙洛菌素对抑制兔球虫卵囊产生,减轻肠道病理损害,降低幼兔死亡率,保护兔只增重和提高饲料转化率的作用极显著优于氯苯胍(P<0.01);氯苯胍抗球虫效果较差,与不给药对照组差异不显著(P>0.05);但较长时间连续使用拉沙洛菌素对兔有较大的毒副作用.试验证明氯苯胍不宜单一长期使用,应选用新型高效抗球虫药或变换用药或联合用药.  相似文献   

3.
本文介绍球必清治疗家兔球虫病的方法和效果,并与球痢灵和华宝沙美耳进行疗效对比。球必清以0.25%剂量拌入干粉饲料中,给自然感染艾美耳球虫病兔连喂17天,结果表明相对增重率显著优于球痢灵组(P<0.01),显著抑制卵囊增殖(P<0.01),药物防治保护率达100%。球必清能有效地控制家兔球虫病的发生,值得推广使用。  相似文献   

4.
Experimental infections with field isolates of Eimeria meleagrimitis, E. adenoeides, E. gallopavonis, and E. dispersa in turkey poults were used to test the efficacy of maduramicin ammonium at 2.5-10 ppm in laboratory experiments. Infection with single or mixed species of coccidia reduced the weight gain of unmedicated infected controls and caused 18.1-65% mortality in two experiments. Maduramicin ammonium given at 5-7 ppm prevented mortality, significantly reduced droppings scores and oocyst passage, and improved weight gain to near that of the unmedicated uninfected controls. Maduramicin ammonium was tested at 4-7 ppm in a floor-pen trial lasting 10 weeks. Mortality from coccidiosis averaged 11.9% in unmedicated controls, compared with 0.6% with 4 ppm of maduramicin or no mortality with 5-7 ppm. Average weight gain and feed conversion at 10 weeks were significantly improved over unmedicated infected controls when maduramicin ammonium was given at 5-7 ppm. These results suggest that maduramicin ammonium is highly efficacious against field isolates of Eimeria in turkeys, especially within the range of 5-7 ppm in the feed.  相似文献   

5.
球痢清等药物对人工感染兔肠球虫病的治疗比较试验   总被引:1,自引:0,他引:1  
48只30日龄大耳白杂种兔,试验接种感染兔肠球虫的5种混合孢子化卵囊,将球痢清I、球痢清Ⅱ、莫能霉素和氯苯胍分别拌在饲料中饲喂,以比较其抗兔肠球虫的效果。通过临床观察,分析克粪便卵囊数的变化,记录增重、计算饲料转化率和对每组扑杀兔作病理组织学检查,结果表明:球痢清抑制卵囊产生、减轻肠道病变、增重及饲料转化率的效果明显,与莫能霉素相近,并显著优于氯苯胍。氯苯胍效果较差,几乎与接种不给药组相同。无显著性差异。因此说明氯苯胍不宜单一继续使用。应引入新的高效抗球虫药,并指导正确使用抗球虫药物。  相似文献   

6.
Vaccines composed of either virulent or attenuated Eimeria spp. oocysts have been developed as an alternative to medication of feed with ionophore drugs or synthetic chemicals. The purpose of this study was to evaluate the use of gel-beads containing a mixture of Eimeria acervulina, Eimeria maxima, and Eimeria tenella oocysts as a vaccine against coccidiosis. Newly hatched chicks (Gallus gallus domesticus) were either sprayed with an aqueous suspension of Eimeria oocysts or were allowed to ingest feed containing Eimeria oocysts-incorporated gel-beads. Control day-old chicks were given an equivalent number of Eimeria oocysts (10(4) total) by oral gavage. After 3 days, chicks were randomly assigned to individual cages, and feces were collected between days 5 and 8 postinfection. All samples were processed for total Eimeria oocysts. At 4 wk of age, all chickens and a control nonimmunized group received a high-dose E acervulina, E maxima, and E. tenella challenge infection. Oocyst excretion by chicks fed gel-beads or inoculated by oral gavage was 10- to 100-fold greater than that of chicks spray-vaccinated with the Eimeria oocysts mixture (log 6.3-6.6 vs. log 4.8). Subsequent protection against challenge as measured by weight gain and feed conversion efficiency was significantly greater (P < 0.05) in gel-bead and oral gavage groups compared with spray-vaccinated or nonimmunized groups. Also, gel-bead and oral gavage groups showed no significant difference (P > 0.05) in weight gain and feed conversion efficiency compared with nonchallenged controls. These findings indicate that incorporation of Eimeria spp. oocysts in gel-beads may represent an effective way to deliver live oocyst vaccines to day-old chicks for preventing subsequent outbreaks of coccidiosis in the field.  相似文献   

7.
The pathology of experimental Eimeria stiedai infection in 2- and 4-month-old rabbits raised coccidia-free was studied. Over 50 days of infection, the serum activities of aspartate (AST) and alanine (ALT) aminotransferases, alkaline phosphatase (AP) and gamma-glutamyltranspeptidase (GGTP) were analyzed as indicators of hepatic lesions and total serum globulins with respect to the immune response of the host; parasite development was followed by oocyst output; weight gain, food intake and relative liver weight were analyzed to control the performance of infected animals. The age of the host strongly affected parasite development and consequently the biochemical and zootechnical parameters differed more markedly in the younger animals; however, the enzyme ALT showed an increase independent of parasite development, and infection did not affect GGTP activity. The increase in age was responsible for resistance of rabbits to hepatic coccidiosis and older animals were less affected than young ones.  相似文献   

8.
The prophylactic efficacy of a single oral dose of toltrazuril against coccidiosis (mixed Eimeria infections) in naturally infected lambs was evaluated in two experiments. Toltrazuril at 20 mg kg-1, given on Day 7 or Day 10 after turnout on pasture, proved to be highly efficacious in preventing clinical coccidiosis under Norwegian conditions. Toltrazuril reduced the oocyst output to very low levels, prevented the development of diarrhoea and improved weight gain during the first 4-5 weeks after treatment. Treatment on Day 7 was superior to treatment on Day 10 with respect to improving weight gain and preventing the development of soft faeces. Lambs treated with toltrazuril on Day 7 seemed to be as immune as untreated lambs to natural reinfections with coccidia later in the grazing season. In one of the experiments, natural infections with the nematode Nematodirus battus produced a coccidiosis-like disease in some lambs simultaneously with the outbreak of coccidiosis.  相似文献   

9.
Lambs naturally infected with mixed species of Eimeria were fed monensin (30 mg/kg of feed) and aureomycin (10 mg/kg of feed) separately and in combination. An evaluation was made of the efficacy of the treatments in the suppression of oocyst production. Comparisons were made of the parasitic damage to the intestinal surface. Performance of the lambs was measured by weight gains and feed efficiency. Monensin given separately or in combination with aureomycin produced decreases in oocyst counts that were not significantly different from those in the lambs given only aureomycin. Body weight gains and feed efficiency were best in the aureomycin-treated group, and less so in the monensin-treated and the control groups. Animals fed the monensin-aureomycin combination had the poorest weight gains and feed efficiency. Scanning electron microscopy indicated that the groups fed monensin or aureomycin separately had morphologically normal intestinal surfaces. This was in contrast to the control group and the group fed the monensin-aureomycin combination, wherein there was disrupted intestinal surface morphology.  相似文献   

10.
The purpose of the present study was to evaluate the species composition and salinomycin sensitivity of Eimeria oocysts isolated from commercial broiler farms that differed by means of coccidiosis control (anticoccidial drugs [ACD] vs. live oocyst vaccines [VAC]). A comparison of Eimeria species composition and salinomycin sensitivity was also made before and after a producer switched from salinomycin to live oocyst vaccines. In general, no significant difference was observed in the concentration of Eimeria spp. oocysts in litter from VAC-utilizing farms compared to litter from ACD-utilizing farms. Application of PCR-based methods to detect coccidia found that Eimeria species distribution in litter from VAC operations more closely resembled the species composition in the live oocyst vaccines. Drug sensitivity testing found that Eimeria oocysts from VAC operations displayed greater salinomycin sensitivity as measured by weight gain and feed conversion efficiency compared to oocysts from ACD farms. These findings provide additional evidence for the usefulness of live oocyst vaccines to restore ionophore sensitivity in poultry operations that contain an ionophore-resistant population of Eimeria spp. oocysts.  相似文献   

11.
A cloned Eimeria acervulina gene (3-1E) was used to vaccinate chickens in ovo against coccidiosis, both alone and in combination with genes encoding interleukin (IL)-1, IL-2, IL-6, IL-8, IL-15, IL-16, IL-17, IL-18, or interferon (IFN)-gamma. Vaccination efficacy was assessed by increased serum anti-3-1E antibody titers, reduced fecal oocyst shedding, and enhanced body weight gain following experimental infection with E. acervulina. When used alone, anti-3-1E antibody titers were transiently, but reproducibly, increased at 2 wk and 3 wk posthatching in a dose-dependent manner. Similarly, significantly reduced oocyst shedding and increased weight gain were observed at relatively high-dose 3-1E vaccinations (> or =25 microg/egg). Combined immunization with the 3-1E and IL-1, IL-2, IL-15, or IFN-gamma genes induced higher serum antibody responses compared with immunization with 3-1E alone. Following parasite infection, chickens hatched from embryos given the 3-1E gene plus the IL-2 or IL-15 genes displayed significantly reduced oocyst shedding compared with those given 3-1E alone, while 3-1E plus IL-15 or IFN-gamma significantly increased weight gain compared with administration of 3-1E alone. Taken together, these results indicate that in ovo immunization with a recombinant Eimeria gene in conjunction with cytokine adjuvants stimulates protective intestinal immunity against coccidiosis.  相似文献   

12.
A 42-day broiler floor pen study was conducted comparing the anticoccidial efficacy of toltrazuril (Baycox) as a stand alone treatment and as an additional treatment to in-feed anticoccidial programs. Toltrazuril was administered on days 18 and 19 in the drinking water at 7 mg/kg of body weight. The treatments were 125 ppm nicarbazin (days 0-14) to 66 ppm salinomycin (SAL) (days 15-35) with and without toltrazuril, SAL (days 0-35) with and without toltrazuril, nonmedicated (NM) to SAL with toltrazuril, and NM with and without toltrazuril. The controls were NM noninfected and infected. The treatments were replicated in five blocks of eight pens each in a randomized complete block design. All withdrawal feed was nonmedicated. On day 14, birds, except noninfected, were exposed to coccidial oocysts (Eimeria acervulina, Eimeria maxima, and Eimeria tenella) seeded litter. On days 21, 28, 35, and 42, birds and feed were weighed, four birds per pen were coccidial lesion scored, and litter oocyst counts were performed. The coccidial infection in the NM infected treatment caused a significant (P < 0.05) coccidiosis infection. Coccidiosis was moderately controlled in the anticoccidial treatment birds without toltrazuril. Performance in the NM with toltrazuril was equal to or better (P < 0.05) than the anticoccidial programs without toltrazuril. Toltrazuril was equal to the noninfected birds in performance. Toltrazuril most completely eliminated all coccidial lesions and dramatically reduced oocyst shedding. The performance data, lesion scores, and oocyst counts showed that a 2-day treatment with toltrazuril successfully controlled the coccidiosis with no relapse of infection. Toltrazuril can thus be used for supplemental control with in-feed anticoccidials or as a primary anticoccidial with nonmedicated feed.  相似文献   

13.
Diclazuril, a new anticoccidial drug, was tested for its efficacy in turkeys against mixed Eimeria infections. A floor-pen trial indicated that diclazuril at dosages of 0.5 ppm and 1 ppm in the feed was highly effective against the major pathogenic species E. adenoeides, E. gallopavonis, and E. meleagrimitis in suppressing intestinal and cecal lesions and oocyst shedding. Weight gain and feed conversion improved, particularly at 1 ppm.  相似文献   

14.
Eimeria parasites were isolated from Nanhai Guangdong province (southern China) and studied in chickens in wire cages to evaluate their drug resistance against commonly used ionophores: monensin (100 mg/kg of feed), lasolacid (90 mg/kg), salinomycin (60 mg/kg), maduramicin (5 mg/kg) and semduramicin (25 mg/kg). Chinese Yellow Broiler Chickens were infected with 40,000 crude sporulated Eimeria oocysts at 15 days of age and prophylactic medication commenced a day prior to infection. Drug resistance was assessed for each ionophore drug by calculating the anticoccidial index (ACI) and percentage optimum anticoccidial activity (POAA) based on relative weight gain, rate of oocyst production and lesion values. Results revealed that Nanhai Eimeria oocysts comprising of E. tenella, E. maxima and E. acervulina, were resistant to monensin, sensitive to both salinomycin and lasolacid and partially sensitive to maduramicin and semduramicin. By selection for early development of oocysts during passage through chickens, the prepatent time of E. tenella, E. maxima and E. acervulina were reduced by 49, 36 and 22 h, respectively. The precocious lines are less pathogenic than the parent strains from which they were selected and conferred a satisfactory protection for chickens against coccidiosis. These ionophore-tolerant precocious lines could have wider applications in the development of anticoccidial vaccines for sustainable control of coccidiosis.  相似文献   

15.
The anticoccidial effect of toltrazuril (Bay Vi 9142) against Eimeria flavescens, E. intestinalis, E. magna, E. perforans and E. stiedai was tested in experimentally-infected rabbits. Continuous administration of 10-15 p.p.m. of the drug in the drinking water was highly effective in reducing oocyst output of all five species and in preventing clinical signs and macroscopic lesions. Sporulation of excreted oocysts was not affected. After 5 weeks of medication, no negative influence was noted on zootechnic performance of growing healthy rabbits. Medication of rabbits with 25 p.p.m. only during schizogony or gamogony (2 days of treatment, repeated after 5 days) quickly reduced clinical signs and oocyst output. When administered during late schizogony or gamogony, toltrazuril allowed development of immunity against reinfection with homologous species.  相似文献   

16.
Male Holstein calves were each inoculated with 350,000 sporulated oocysts of Eimeria bovis. Two calves were given decoquinate (0.5 mg/kg of body weight) continuously in dry feed for 29 days, and 2 calves each were given 0.5, 1, or 1.5 mg of decoquinate/kg on an every 2nd-or 3rd-day schedule for 29 days. Calves given decoquinate continuously did not discharge oocysts but had slightly loose feces. In general, the number of oocysts discharged increased and fecal consistency decreased as the time between feeding of medicated feed increased. Calves given 0.5 or 1.5 mg of decoquinate/kg every 3rd day discharged more oocysts and had more diarrhea than did calves given 1 mg of decoquinate/kg every 3rd day. At postinoculation day 29, calves were euthanatized. At necropsy, intestinal tissues of calves given decoquinate were mostly normal. Apparently, reduced infections along with the elapsed time were sufficient to resolve most intestinal lesions caused by the coccidia. Decoquinate was most effective when fed continuously at 0.5 mg/kg. However, when fed at 1 or 1.5 mg of decoquinate/kg every 2nd day or 1.5 mg of decoquinate/kg every 3rd day, oocyst production was reduced and clinical coccidiosis was prevented.  相似文献   

17.
To determine whether northern bobwhite quail (Colinus virginianus) could be immunized against Eimeria lettyae by a low-dose inoculation of oocysts, we inoculated 30 birds each with either 100 or 1000 oocysts at 2 days of age (given orally by pipette). Four weeks after immunization, the immunized birds and unimmunized controls were challenged with 1 x 10(6) E. lettyae oocysts. Eight days after challenge, birds were killed and weighed, and their intestines examined for gross lesions. Effectiveness of the immunization was measured by analyzing weight gain, intestinal lesions, severity of diarrhea, feed conversion ratio, and oocyst production. After challenge, birds immunized with 100 or 1000 oocysts gained an average of 33.3 g and 28.9 g, respectively, whereas unimmunized challenged birds gained an average of 11.5 g. Immunized quail produced approximately 99.7% fewer oocysts, had minimal gross intestinal and cecal lesions, had minimal diarrhea, and had a 50% lower feed conversion ratio compared to unimmunized challenged controls. These findings indicate that vaccination is a viable option for controlling coccidiosis in quail and that further research into vaccination is warranted.  相似文献   

18.
1. The effect of intestinal digesta viscosity on bird performance in chickens with coccidiosis was compared to those without coccidiosis. 2. Six hundred chicks were divided into five groups: one control group was fed a basal maize/soyabean-based diet and the other groups were fed the basal diet supplemented with 2, 4, 6 or 8 g carboxymethyl cellulose (CMC) per kg of feed. At 14 d of age half the birds were individually inoculated with sporulated oocysts of Eimeria acervulina and Eimeria praecox. 3. Intestinal digesta viscosity increased with increasing inclusion of CMC. This effect was considerably less pronounced in inoculated than in non-inoculated birds. 4. There was a significant negative effect on live weight gain and feed conversion ratio (FCR) with increasing CMC inclusion in non-inoculated birds, but in inoculated birds there was no clear relation between CMC inclusion and performance. Neither intestinal lesion scores, nor numbers of Clostridium pefringens in the caeca, were significantly affected by CMC inclusion. 5. Across all diets inoculation impaired growth rate by 9% and FCR by 8%, but did not affect the amount of C. perfringens in the caeca.  相似文献   

19.
Broiler chickens in battery pens were either fed a diet containing 100 ppm lasalocid or no drug for 24 h prior to inoculation with sporulated oocysts of Eimeria tenella or Eimeria acervulina. Different groups of birds remained on medicated feed for 24, 48, 72, 96, 120 or 144 h after inoculation. Conversely, other groups started on an unmedicated diet, were given medicated feed at different times after oocyst inoculation. Starting lasalocid medication 24 h (E. tenella) or 48 h (E. acervulina) after inoculation reduced the lesions and improved the weight gain. There was no significant difference in performance of birds after withdrawal of the drug at 48 h (E. tenella) or 72 h (E. acervulina) and thereafter. Starting lasalocid medication at 96 or 120 h did not suppress but rather reduced oocyst production.  相似文献   

20.
Diclazuril, a new anticoccidial drug, was tested for its efficacy against Eimeria dispersa in turkeys. A dose-titration study indicated that diclazuril at dosages of 0.5, 1, and 2 ppm in the feed was highly effective in terms of weight gain and suppression of lesions, abnormal droppings, and oocyst shedding.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号