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 15 毫秒
1.
Two experiments were conducted to evaluate lasalocid as a coccidiostat in Holstein calves and to compare lasalocid with monensin and decoquinate. In experiment 1, calves in 3 groups (6 calves/group) were each inoculated with 500,000 sporulated oocysts, 88% of which were Eimeria bovis and 12% were E zuernii. Calves in each group were given lasalocid-medicated feed at 0.50 (group 3), 0.75 (group 4), or 1 mg/kg (group 5) of body weight/day for 45 days. Two control groups (6 calves/group) were also evaluated; calves in control group 2 were inoculated and nontreated, and calves in control group 1 were noninoculated and nontreated. At 0.50, 0.75, or 1 mg/kg/day, lasalocid was equally effective in preventing induced coccidiosis (E bovis and E zuernii) in calves. Compared with inoculated nontreated controls, treated calves had significantly (P less than 0.05) fewer oocysts in feces and had fewer clinical signs of coccidiosis from days 16 to 30 after inoculation. Experiment 2 was conducted to compare the effectiveness of monensin, lasalocid, and decoquinate for the prevention of experimentally induced coccidiosis. Calves (n = 48) were allotted into 4 groups (12 calves/group); each was inoculated orally with 275,000 sporulated oocysts, predominantly E bovis and E zuernii, and each was given nonmedicated feed (group 6) or feed medicated with 33 mg of lasalocid (group 7), decoquinate (group 8), or monensin (group 9)/kg of feed for 46 days. Calves given medicated rations had significantly (P less than 0.05) fewer oocysts in their feces and fewer clinical signs of coccidiosis than did calves given nonmedicated rations.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
Seven beagles in a colony of dogs had chronic diarrhea for at least 30 days. The dogs were subsequently treated with tylosin 20 mg/kg BW q24h PO for 10 days. During the treatment period, the feces became firmer but remained loose. When the treatment was discontinued, the diarrhea reappeared in 3 weeks. The feces remained abnormally loose in all dogs treated with metronidazole, trimethoprim-sulfadiazine, or doxycycline and prednisone. The diet was then changed for 10 days from a highly digestible moist pet food to a dry food developed for normal adult dogs. The feces again became firmer, although still loose in some dogs. The period was then extended to 3 month, but the fecal consistency continued to fluctuate from ideal to diarrhea. The dogs were treated a 2nd time with tylosin 20 mg/kg BW q24h PO for 10 days. The feces then became significantly firmer and remained so throughout a 3-month follow-up. We conclude that the combination of diet and tylosin was more effective than either agent alone in control of chronic diarrhea.  相似文献   

3.
We compared the therapeutic effect of three anticoccidial drugs (toltrazuril, sulphadimidine and amprolium) in buffalo (Bubalus bubalis) calves experimentally infected with Eimeria bovis (E. bovis) and E. zuernii oocysts (3 x 104oocyst/calf). Buffalo calves (1.5-4 month old, 70-kg body weight) were randomly allocated into 3 groups (9 calves each). Group T was experimentally infected with oocysts and treated with toltrazuril (20 mg/kg BW twice orally at a 1-week interval). Group S was experimentally infected with oocysts and treated with sulphadimidine (125 mg/kg injected IM followed by half dose for 4 successive days). Group A was experimentally infected with oocysts and treated with amprolium (50 mg/kg orally for 7 successive days). Each group had three subgroups (three calves/subgroup) to represent timing of the drug administration: 1st day of coccidia infection (FD), onset of clinical signs of coccidiosis (CC), and onset of oocyst shedding into the faeces (OS). Clinical signs, body-weight gain (BWG) and number of oocysts per gram feces (OPG) were monitored daily for 35 days post-infection (DPI). The OPG were reduced (but the BWG was not different) in the T calves compared to S and A calves. Within the same group, treatment from the 1st day of infection reduced the OPG and increased the BWG compared to the later treatment timings.  相似文献   

4.
Twenty coccidia-free Holstein bull calves were allotted to groups to study effects of treatment with lasalocid and decoquinate on subsequent resistance to coccidiosis (Eimeria spp infections). Calves fed medicated rations of either drug at dosages of 50 mg/kg of feed (approx 1.2 mg/kg of body weight) had significantly fewer oocysts (P less than 0.01) than did nontreated controls regardless of other procedures used. Treated calves premunized with 2,000 oocysts/day for 5 days and later challenge inoculated with 200,000 oocysts did not develop diarrhea, unless the drugs were withdrawn from feed. Animals premunized (2,000 oocysts/day for 5 days) in absence of drug were no more resistant to the challenge inoculation than nonpremunized animals. These results indicated that lasalocid and decoquinate were efficacious coccidiostats and protected calves as long as they were administered. Cessation of drug treatment usually resulted in appearance of oocysts in feces and diarrhea. Premunization alone cannot be expected to prevent coccidiosis when animals are exposed to large numbers of oocysts.  相似文献   

5.
Efficacy of praziquantel against Nanophyetus salmincola, the trematode vector of salmon poisoning disease, was determined in coyotes (n = 29) and dogs (n = 25). The 10- to 14-week-old animals were fed fish or fish kidneys that contained metacercariae of N salmincola. To prevent salmon poisoning disease, all animals were treated with tetracycline on days 8 and 9 after they were fed fish. Ten days after ingestion of infected fish, 19 coyotes and 12 dogs were treated once with praziquantel, administered SC or IM, at dosages between 6.68 and 38.73 mg/kg of body weight. Within 8 days after treatment, the numbers of trematode eggs in feces and trematodes recovered from the small intestine were reduced by greater than 99% when compared with untreated controls. Signs of drug toxicosis were not observed. On the basis of these results, praziquantel at doses approved for use in dogs against cestodes was highly effective against N salmincola in coyotes and dogs.  相似文献   

6.
Decoquinate was evaluated as a coccidiostat in domestic goats. Fifty goats less than 4 months of age were assigned to 5 groups (pens) of 10 goats each and were treated for 87 days with 0 (control), 0.3, 0.5, 1.0, or 4.0 mg of decoquinate in feed/kg of body weight. Goats were inoculated orally weight. Goats were inoculated orally with 30,000 oocysts, mainly Eimeria christenseni (74%) and E ninakohlyakimovae (20%) on day 19. Nontreated goats developed profuse watery diarrhea and tenesmus and gained weight poorly; 2 died. Treated goats did not develop clinical coccidiosis and gained significantly more weight (P less than 0.05), regardless of the dose used. Treated goats also had significantly fewer (P less than 0.05) oocysts in feces than did nontreated controls. Oocyst numbers were inversely related to dose; a more rapid decrease in oocyst numbers occurred as the dose was increased. At the doses used, decoquinate was safe in goats and was an effective drug for the prevention of clinical coccidiosis.  相似文献   

7.
Cystitis was produced in 4 groups of 6 female dogs each, using salicylic acid, ethanol, and Staphylococcus intermedius. Group-I dogs served as nontreated controls. Starting 2 days after infection was induced, group-II dogs were treated with trimethoprim-sulfadiazine at a dosage of 15 mg/kg given orally 2 times a day for 21 days; groups-III and -IV dogs were treated with single oral dosages of the antibiotic at 60 mg/kg and 90 mg/kg, respectively. Group-I dogs (controls) remained infected for the 26-day duration of the study. The response to therapy seen in group-II dogs was better than the therapeutic responses in groups-III and -IV dogs (P less than 0.05). Results of the present study do not support the efficacy of single-dose therapy for this model of cystitis.  相似文献   

8.
Forty‐four faecal samples from piglets (2–3 animals per group) experimentally infected with Isospora suis were examined 4, 5, 7, 10, and 11 days after infection either with a modified flotation technique followed by McMaster counting (MM), MM combined with autofluorescence microscopy of faecal smears (MM‐A), or nested‐polymerase chain reaction (PCR). PCR was the most sensitive method, detecting I. suis in 70% of the samples (MM 25%, MM‐A 52%). More positive samples were detected in the untreated and the diclazuril‐treated [15 mg/kg bodyweight (BW) once or twice, respectively] groups (10 samples per group; MM 30–40%, MM‐A 50–70%, PCR 60–90%), than in the toltrazuril‐treated (20 mg/kg BW) group (14 samples; MM 0%, MM‐A 21%, PCR 57%). Parasites could be detected in the untreated group on all days with PCR and MM‐A, while MM detected oocysts only from day 5. Autofluorescence should be used as a routine diagnostic aid for the detection of oocysts in faecal samples, while PCR, being the most sensitive technique, can be employed when large numbers of samples are examined, and in experimental setups.  相似文献   

9.
Selected pharmacokinetic parameters for sulfadimethoxine and ormetoprim, administered in a 5:1 ratio, via the oral and intraperitoneal (i.p.) routes were determined in the hybrid striped bass (Morone chrysops x Morone saxitalis). Plasma concentrations of both drugs were determined by high-performance liquid chromatography. A first-order one-compartment model adequately described plasma drug disposition. The elimination half-lives for sulfadimethoxine following i.p. and oral administration were 26 and 10.5 h, respectively. The half-lives for ormetoprim administered via i.p. and oral routes were 7.5 and 3.9 h, respectively. Cmax for sulfadimethoxine via the i.p. and oral routes were calculated to be 27.7 (+/-9.0) microg/mL at 3.6 h and 3.2 (+/-1.2) microg/mL at 1.2 h, respectively. Cmax for ormetoprim via the i.p. route was calculated to be 1.2 (+/-0.5) microg/mL at 9.1 h and 1.58 (+/-0.7) microg/mL at 5.7 h for the oral route. The oral availability of sulfadimethoxine relative to the i.p. route was 4.6%, while the oral availability of ormetoprim relative to the i.p. route was 78.5%. Due to the nonconstant ratio of these drugs in the plasma of the animal, the actual drug ratio to use for determining minimum inhibitory concentration (MIC) is unclear. Using the ratio of the total amount of each drug that is absorbed as a surrogate for the mean actual ratio may be the best alternative to current methods. Using this ratio as determined in these studies, (2.14:1 sulfadimethoxine:ormetoprim) to determine the MICs the single 50 mg/kg oral dose of the 5:1 combination of sulfadimethoxine and ormetoprim appears to provide plasma concentrations high enough to inhibit the growth of Yersinia ruckeri, Edwardsiella tarda, and Escherichia coli.  相似文献   

10.
Twenty-four specific-pathogen-free Beagles were each given 50 cysticerci of Taenia pisiformis that had been harvested from experimentally infected rabbits. Quantitative fecal egg counts and fecal screening for recovery of passed segments were performed on postinoculation days 56 through 70. Twenty-three of 24 dogs fed cysticerci developed patent infections. The 23 dogs with patent infections were assigned to 1 of 2 groups and treated with nitroscanate or a placebo 60 days after inoculation. Egg counts in the treated dogs had markedly decreased by the second day after treatment, and by the sixth day after treatment, segments were not found in the feces of any of the treated animals. The control dogs continued to pass eggs and segments in their feces throughout the 9 days after treatment. The dogs were euthanatized and necropsied 70 days after being inoculated. At necropsy, the mean number of scolices recovered from control dogs was 24.6, the mean number of scolices recovered from treated dogs was 0.25. Worms recovered from the control dogs were intact, gravid cestodes. Efficacy of treatment with nitroscanate at a mean dosage of 56 mg/kg of body weight was 98.9%.  相似文献   

11.
Effects of feeding sulfadimethoxine and ormetoprim to sows and gilts in late gestation were evaluated. One sow and 2 gilts were randomly selected and were fed 1 of 3 rations: (1) a gestation ration from farm A, where congenital goiter in newborn pigs was a problem, (2) gestation ration from farm A containing 275 g of sulfadimethoxine and 55 g of ormetoprim/100 kg of ration, or (3) standard swine gestation ration containing 275 g of sulfadimethoxine and 55 g of ormetoprim/100 kg of ration. Sows and gilts were fed the appropriate ration for 22 to 58 days before farrowing. The numbers of stillborn or weak pigs did not increase in any group. However, congenital goiter was detected in all pigs from swine fed medicated rations 2 and 3. Congenital goiter was not present in pigs from swine given gestation ration 1.  相似文献   

12.
Pan BL  Zhang YF  Suo X  Xue Y 《The Veterinary record》2008,162(5):153-155
The effect of subcutaneously injected diclazuril on the output of Eimeria species oocysts was studied in experimentally infected rabbits. Diclazuril was administered either prophylactically at 0.5, 1 or 2 mg/kg bodyweight two days before each rabbit was inoculated with 20,000 oocysts of a mixed-species field isolate of Eimeria or therapeutically at 1, 2 or 4 mg/kg bodyweight five days after they were inoculated. The prophylactic treatments significantly reduced (P<0.05) the output of oocysts in faeces and the numbers in the rabbits' livers at all doses. The therapeutic treatment at 4 mg/kg also caused a significant reduction (P<0.05) in oocyst shedding, but the lower doses resulted in only a moderate reduction. The shedding of the pathogenic species Eimeria stiedae, Eimeria magna, Eimeria irresidua, Eimeria flavescens, Eimeria piriformis and Eimeria intestinalis was significantly reduced (P<0.05) in all the treated groups. The burden of oocysts in the livers of the therapeutic groups (4000 to 9000) were significantly lower (P<0.05) than in the inoculated but untreated control group (23,000), but higher than in the prophylactic groups (around 1000).  相似文献   

13.
Experimental infection of dogs with camel (Camelus dromedarius) meat resulted in infection of the dogs with Isospora canis, Hammondia heydorni and Sarcocystis cameli. The dogs fed sheep (Ovis aries) meat passed oocysts of Isospora canis, Isospora ohioensis and sporocyts of Sarcocystis spp. Extraintestinal stages were detected in the intestinal lymph node of a rabbit killed 4 days following inoculation with Isospora ohioensis oocysts. Dogs fed the rabbit (killed 4 days after inoculation with I. ohioensis) passed I. ohioensis oocysts in their faeces 8 days post-infection.  相似文献   

14.
Neospora caninum is widely distributed in the world and this parasite is one of the major causes of abortion in cattle. Dogs and coyotes are definitive hosts of N. caninum and several species of domestic and wild animals are intermediate hosts. Dogs can become infected by the ingestion of tissues containing cysts and then excrete oocysts. It is not yet known whether sporulated oocysts are able to induce a patent infection in dogs, i.e. a shedding of N. caninum oocysts in feces. The objective of this study was to experimentally examine the infection of dogs by sporulated oocysts. The oocysts used in the experiment were obtained by feeding dogs with brain of buffaloes (Bubalus bubalis) positive for anti-N. caninum antibodies by indirect fluorescent antibody test (IFAT ≥200). Oocysts shed by these dogs were confirmed to be N. caninum by molecular methods and by bioassay in gerbils, and sporulated N. caninum oocysts were used for the oral infection of four dogs. The dogs were 8 weeks old and negative for antibodies to N. caninum and Toxoplasma gondii. Dogs 1 and 4 received an inoculum of 10,000 sporulated oocysts each; dog 2 an inoculum of 5000 sporulated oocysts and dog 3 received 1000 sporulated oocysts of N. caninum. The total feces excreted by these dogs were collected and examined daily for a period of 30 days. No oocysts were found in their feces. The dogs were monitored monthly for a 6-month period to observe a possible seroconversion and when this occurred the animals were eliminated from the experiment. Dogs 1 and 4 seroconverted 1 month after the infection with titer, in the IFAT, of 1600 and 800, respectively; the other two dogs presented no seroconvertion during the 6-month period. Dogs 1 and 2 were euthanized 180 days after infection and were examined for the detection of N. caninum in tissues (brain, muscle, lymph node, liver, lung, heart and bone marrow) by immunohistochemistry and PCR with negative results in both techniques. Bioassay in gerbils with brain of these dogs was also performed and again the results were negative. In conclusion, dogs infected with sporulated oocysts of N. caninum were not able to shed oocysts in feces. However, a higher dose of infection stimulated the production of antibodies against N. caninum in the dogs.  相似文献   

15.
In this study, we evaluated the efficacy of monensin as a preventive therapy for porcine neonatal coccidiosis. Fifteen three-day-old piglets were given 50,000 sporulated oocysts of Isospora suis and eight of them received 15 mg/kg of monensin orally every other day. Seven piglets served as normal controls. Fecal samples were collected and checked for oocyst shedding. At 18 days of age, piglets were euthanized and necropsied.

The onset of clinical signs was delayed in the treated group, but all inoculated piglets displayed anorexia, soft stool, or diarrheic feces. Treated piglets shed large numbers of oocysts in their feces (up to 201,200 oocysts per gram of feces). All infected piglets had lesions of villous atrophy in the jejunum and most of them were in the late atrophic or villous regrowth stages.

The results of this study suggest that monensin does not prevent clinical signs, oocyst shedding, and intestinal lesions caused by I. suis in neonatal piglets.

  相似文献   

16.
Hematophagous gastrointestinal parasites cause significant economic losses in small ruminant grazing systems. The growing reports of multi-drug resistant parasites call for intensive research on alternative treatments for anthelmintics to help small ruminants cope with these parasites. Two-month-old lambs with mean body weight (BW) of 22.5 kg were experimentally infected with a multidrug-resistant Haemonchus contortus strain. Infected animals were dosed orally with Cymbopogon schoenanthus essential oil to evaluate its anthelmintic potential. Eighteen animals were allocated into three groups of six animals, and each received one of the following treatments: Group 1 - control (10 mL of water), Group 2 - C. schoenanthus essential oil (180 mg/kg BW); and Group 3 - C. schoenanthus essential oil (360 mg/kg BW). Animals received the oil once a day for 3 consecutive days. Lambs were evaluated clinically for blood biochemistry before, at 1, 5, 10, 15 and 20 days after treatment, and then were euthanized to assess the total worm burden. No statistically significant reduction in fecal egg count, packed cell volume or total worm count was observed after treatments. Also, no statistical difference among group means for blood levels of urea, creatinine, albumin, alkaline phosphatase, aspartate aminotransferase and gamma glutamyl transferase was found. Larval development assay (LDA) and egg hatch assay (EHA) were performed from feces of treated animals at 1, 5, 10 and 15 days after essential oil administration. An inhibition in LDA was observed 1 day after the 3-day treatment in larvae from feces of animals treated with 360 mg/kg essential oil. In conclusion, the essential oil at the doses of 180 mg/kg and 360 mg/kg was safe to sheep, but failed as an anthelmintic treatment when applied to young sheep artificially infected with a multidrug-resistant H. contortus strain.  相似文献   

17.
One thousand and eighty-five newly received, stressed calves were used in studies to determine the effectiveness of certain mass medication procedures for reducing morbidity from shipping fever-bovine respiratory disease complex. In two experiments, im injections of oxytetracycline at 11 mg/kg body wt for 3 successive days reduced treatment days/calf purchased 21 (P less then .05) and 31% (P less than .05). Oral administration of 150 mg of sulfadimethoxine/kg body wt reduced treatment days/calf purchased 20 (P less than .05) and 54% (P less than .05) in the same two experiments. When sulfadimethoxine followed oxytetracycline on the third injection day an 81% reduction in treatment days/calf purchased was obtained, indicating an additive effect of the two drugs. The use of long acting oxytetracycline and sustained release sulfadimethoxine at the time of processing resulted in a 90% reduction in treatment days/calf purchased (P less than .01) and required only one handling of the calves for mass medication purposes.  相似文献   

18.
Ibuprofen (IBU)-a nonsteroidal anti-inflammatory drug-inhibits the biosynthesis of prostaglandins with pro-inflammatory and immunosuppressive properties and is therefore proposed as a candidate molecule for the treatment of coccidiosis in broiler chickens. In all experiments, IBU was administered via drinking water. In a first experiment, chickens were infected at 10 or 21 days of age with oocysts of Eimeria acervulina (5 X 10(4)), Eimeria maxima (3 X 10(4)), and Eimeria tenella (7.5 X 10(3)) and medicated with IBU at a dose of 15 mg/kg body weight (BW). In a second experiment, chickens were infected at 6 days of age with 10(4) oocysts of E. acervulina and medicated with IBU at a dose of 100 mg/kg BW. In the third experiment, an inoculum consisting of 5 x 10(4) or 10(5) E. acervulina oocysts was administered at 6 days of age to chickens medicated with IBU at a dose of 100 mg/kg BW. In a fourth experiment, the effect of IBU on sporulation and infectivity of E. acervulina oocysts was studied. Coccidial lesion scores (CLSs), oocyst shedding, and weight gain were used as evaluation parameters in all experiments except the fourth, where weight gain was not taken into account. In addition, the sporulation percentage was determined in the last experiment. No influence of IBU on the indicated parameters was observed after providing the drug at a dose of 15 mg/kg BW, whereas CLSs and oocyst shedding were reduced when IBU was provided at a dose of 100 mg/kg BW. However, IBU did not significantly show any effect on the degree of sporulation and infectivity of E. acervulina oocysts at a dose of 100 mg/kg BW.  相似文献   

19.
To determine the drug dose required to inhibit platelet reactivity by at least 50%, 2 drug regimens were evaluated in heartworm-negative, heartworm-infected, and heartworm-infected dogs embolized with dead heartworms. Aspirin, or a combination of aspirin and dipyridamole, were administered to 2 groups of Beagles (n = 5 each) for 5 to 9 days; a third group of 5 Beagles served as nontreated controls. For heartworm-negative dogs, mean (+/- SD) aspirin dosage that inhibited collagen-induced platelet reactivity by at least 50% was 6 (+/- 2) mg/kg of body weight given once daily. The aspirin/diphridamole combination dosage was 1 mg of each drug/kg given every 12 hours. All dogs (n = 15) were implanted with 7 adult heartworms each and remedicated (or not treated) beginning at 21 days after heartworm implantation. In heartworm-infected dogs, mean aspirin dosage required to inhibit collagen-induced platelet reactivity greater than or equal to 50% was 10 (+/- 6) mg/kg. Mean dosage of aspirin/dipyridamole combination was 1.6 +/- (0.5) mg of each drug/kg given every 12 hours. When platelet reactivity in response to collagen was determined to be inhibited by at least 50% in all medicated dogs, each dog (n = 15) was embolized with 7 dead adult heartworms to mimic heartworm adulticidal treatment. Platelet reactivity was monitored for 21 days after treatment, and drug dose was adjusted to maintain platelet inhibition by at least 50%. In embolized dogs, mean aspirin dosage was 17 (+/- 14) mg/kg given once daily. Mean dosage of the aspirin/dipyridamole combination was 2.8 (+/- 1.3) mg of each drug/kg given every 12 hours. All dogs (n = 15) were euthanatized 21 days after heartworm embolization. Each lung lobe was evaluated for severity of lesions and presence of organized or fibrinous thrombi. Lesion severity in the aspirin- and aspirin/dipyridamole-treated dogs was not significantly different from that in control dogs.  相似文献   

20.
Isospora spp. are the causative agents of canine isosporosis. Of the 3590 diagnostic samples from Austrian dogs (< or = 2 years old), 8.7% contained Isospora oocysts, 78% of which from dogs up to 4 months of age. Non-haemorrhagic and haemorrhagic diarrhoea were significantly more prevalent in Isospora-infected animals than in coccidia-negative ones. Twelve of 15 litters from a large commercial dog breeding unit (examined from the third to the 10th week of life) also excreted Isospora (average prevalence: 36.4%) in intensities from 333 to 35,000 oocysts per gram of faeces (opg). In experimental trials 26 3-week-old Beagle puppies were infected with low (600-6000), medium (10,000) or high (20,000) dose of Isospora ohioensis-group or Isospora canis field isolates. Additionally 21 puppies were infected as above and treated with a symmetrical triazintrione. Parasitological and clinical parameters were examined. The two Isospora species differed significantly concerning intensity and duration of excretion. The pre-patent period was 6-7 days for I. ohioensis and 10-12 days for I. canis. The latter species showed significantly longer excretion and higher opg. This was not influenced by simultaneous infections with both species. Individual patterns of faecal consistency were very variable, irrespective of the infection dose. Treatment significantly reduced both the intensity and the duration of oocysts excretion as well as diarrhoea in comparison with the infected, untreated group and thus proved to be effective against coccidiosis in experimental infections.  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