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1.
For two consecutive years, determinations were made of the prevalence and abundance of coccidian oocysts from crossbred beef calves raised on Bahia grass pastures in the coastal plain area of Georgia. Of the 534 fecal samples collected during the survey, 461 (86.3%) contained one or more species of coccidian oocysts. The total mean oocysts per gram of feces (OPG) was significantly different (P less than 0.10) between the two years. Thirteen species of Eimeria were found during both years of the survey. Eimeria bovis was the most prevalent species found in the survey; E. ellipsoidalis, however, had the greatest number of OPG. Eimeria bukidnonensis, E. pellita, and E. brasiliensis were the least prevalent species and also had the lowest numbers of OPG. Only one clinical case of coccidiosis was seen. A nine-month-old calf had E. zuernii coccidiosis; it excreted E. zuernii oocysts in several fecal samples before the clinical disease appeared.  相似文献   

2.
Macroscopically visible spherical cysts measuring up to 260/μm in diameter and showing characteristics typical of those of the genus Besnoitia were observed in rats dosed with isosporan oocysts recovered from the faeces of a feral cat. Kittens fed these rats shed similar oocysts measuring 16.9 ± 0.1 × 14.6 ± 0.1 μm in their faeces 11–12days later. The feeding of sporulated oocysts of this coccidian to mice, rats, rabbits and guinea pigs resulted in the formation of Besnoitia cystsin all hosts except the last.

Besnoitia is the fourth sporozoan genus, together with Isospora, Toxoplasma, and Sarcocystis to be recovered from New Zealand cats.  相似文献   

3.
The prevalence and numbers of coccidian oocysts in faecal samples from young (less than 6 months old), immature (6–12 months old) and adult (over 12 months old) sheep on 15 farms in Nyandarua district were studied during the dry and wet seasons. The species ofEimeria occuring in these sheep were also identified. The proportion of animals shedding coccidian oocysts did not vary significantly with season. The prevalence of the oocysts was significantly higher (p<0.05) in young sheep (mean 85.3%) compared to immature (mean 40.2%) and adult sheep (mean 32.15%). OPG counts (oocysts per gram of faeces) were significantly higher (p<0.01) in the young sheep compared to immature and adult sheep during both seasons. Prevalence and OPG did not differ between immature and adult sheep. There was no significant difference in OPG during the wet season (mean 328±997) compared to the dry season (mean 219±773). The sex of the sheep had no significant effect on prevalence or OPG. Eight species ofEimeria were recognized. They (and their prevalence) wereE. bakuensis (ovina) (43.6%),E. ovinoidalis (23.6%),E. ahsata (15.2%),E. intricata (8.27%),E. granulosa (4.8%),E. faurei (2.8%),E. parva (1.06%) andE. pallida (0.67%).Abbreviations OPG oocysts per gram of faeces  相似文献   

4.
The present paper reports the prevalence of coccidiosis in industrial broiler chickens in Faisalabad, Punjab, Pakistan to determine the occurrence of different species of Eimeria in the area and to assess their correlation with the environmental conditions including temperature, humidity and rainfall. The study was conducted from January 2009 to December 2010. Examination of chicken guts revealed 43.89% (n = 3,283/7,480) prevalence of coccidiosis. The highest prevalence (27.04%) was recorded of Eimeria tenella followed by Eimeria maxima (22.42%), Eimeria acervulina (19.89%) and Eimeria necatrix (4.02%). The prevalence of disease was significantly higher (P < 0.05) in autumn (60.02 ± 4.38) followed by summer (47.42 ± 2.92), spring (36.92 ± 2.27) and winter (29.89 ± 3.43). Likewise, prevalence of different species of Eimeria also varied (P < 0.05) in different seasons of the year except that of E. necatrix. A strong correlation (P < 0.05) of environmental conditions with the overall and species-wise prevalence of coccidiosis was recorded except E. necatrix.  相似文献   

5.
A crude resinous extract from Commiphora swynnertonii was tested against an experimental coccidial infection in local chickens. A total of 80 growing chickens were randomly assigned into five groups, which received different treatments. Chickens in G1 were not infected with coccidian oocysts and therefore served as a negative control. All chickens in G2, G3, G4 and G5 were infected through oral administration of coccidian oocysts suspension at a dosed rate of 1.5?×?104 Eimeria spp. oocysts per bird. Starting from day 3 post-infection (p.i), chickens in different groups were treated for 7 consecutive days as follows: G1 and G2 (positive control) received 5 ml of normal saline as placebo, G3 and G4 were given the extract at 400 and 800 mg/kg bodyweight whereas G5 received anticoccidial drug. Clinical signs, bodyweights, oocysts counts and mortality rates were observed regularly. Results showed that oral administration of the resinous extract to chickens with coccidiosis significantly reduced mortality rate from 94 to 25 % and oocysts counts from 1.03?×?105 to 6.55?×?103 oocysts/g faeces (p?<?0.05). Also a body condition score chart indicated less severe clinical signs of the disease in the groups which received the extract. Mean daily body weights were slightly reduced by the administration of the extract but this effect disappeared by day 7 p.i. These findings clearly indicate that resinous extract from C. swynnertonii has significant anticoccidial effect against experimental Eimeria spp. infection in chickens. A larger field trial to validate the use of the extract in chickens naturally infected with Eimeria spp. is required.  相似文献   

6.
Abstract

The coccidian Eimeria southwelli is associated with chronic fatal disease in captive cownose rays Rhinoptera bonasus. Clinical signs include discoloration of the epidermis, emaciation, coelomic cavity distention, and death. The oocysts can be demonstrated in coelomic fluid obtained by coelomic aspiration. Prevalence of E. southwelli in wild cownose rays was 92% in Pamlico Sound, North Carolina, USA. Recommended management practices include strict quarantine and screening by using coelomic cavity aspirate sampling. A dosage of 10 mg toltrazuril/kg orally once a day for 5 d reduces but may not eliminate parasitic loads.  相似文献   

7.
Coccidia in cows and calves on pasture in north Georgia (U.S.A.)   总被引：2，自引：0，他引：2  
The prevalence and abundance of coccidian oocysts were determined in a herd of beef cows and calves on fescue pastures in the Piedmont area of Georgia during 4-consecutive grazing seasons. Twelve species of Eimeria were found in the feces of the calves and 10 species were found in the feces of the cows. Eimeria bovis was the most prevalent species found in both the calves and cows. It occurred in 72.5% of 1090 samples from the calves and 10.2% of 719 samples from cows. Eimeria bovis also comprised the majority of oocysts present in the fecal samples from the calves and cows. The greatest number of E. bovis in a sample was 45 800 oocysts per gram of feces (OPG) from a calf and 1900 OPG from a cow. No cases of clinical coccidiosis were seen in any of the animals sampled during the survey.  相似文献   

8.
The presence of Eimeria spp. oocysts in fecal samples collected from 1,108 broiler houses in six regions, representing about 12% of all broiler farms in Turkey, was studied using the modified McMaster method. The age of the chickens in the 1,108 pens varied from 1 to 50 days. Oocysts were found in 602 (54.3%) of these broiler houses, and the mean OPG (oocysts per gram of feces) in those samples was 36,498.7 (50–952,000). No indication of clinical coccidiosis or other clinically evident infection or wide mortality was encountered in any of the pens studied. Further study showed that the age of the chickens, the occurrence of diarrhea on the houses and the density of broiler breeding in the area correlated with subclinical coccidiosis prevalence.  相似文献   

9.
Porcine neonatal coccidiosis in quebec   总被引：8，自引：2，他引：6       下载免费PDF全文
Intestinal coccidiosis was diagnosed in 110 diarrheic piglets originating from 66 farrowing operations. These piglets had been submitted alive for necropsy early after the beginning of diarrhea, and the diagnosis of coccidiosis was based on the demonstration of coccidial forms in their jejunum by histopathological examination. Enteropathogenic strains of Escherichia coli were demonstrated in only nine of the 110 piglets while the transmissible gastroenteritis virus and rotavirus were each present in three pigs. The most common lesion was a multifocal villous atrophy in the middle and lower jejunum, and ileum of the affected pigs. Coccidial forms were present in variable numbers of the cells lining the affected villi and they were mainly asexual stages (meronts and merozoites).

In the affected farrowing houses diarrhea began between five and 15 days of age with the highest frequency around seven to ten days of age. Morbidity rates were very variable and mortality was less than 20%. The disease was a persistent problem in large farrowing operations on continuous farrowing programs, and losses were due mainly to retarded growth and treatment costs which were usually inefficient. The disease occurred year round with the highest prevalence in summer and fall months, and in January.

Search for oocysts in fecal samples or colonic contents from 28 of the 110 pigs revealed that 13 of them were shedding oocysts identified as Isospora suis.

  相似文献   

10.
Abstract

AIMS: To estimate the seroprevalence of antibodies to Erysipelothrix rhusiopathiae in chickens in New Zealand, and to estimate the effect of housing type, geographical location and age on seroprevalence.

METHODS: A cross-sectional serological survey of a convenience sample of 545 broiler, breeder, and layer chickens in 55 flocks was conducted in 2010–2011. Birds were aged 5–83 weeks; housing types were free-range, shed, caged, and unknown; and flocks were located in the Auckland, Manawatu, North Canterbury, Otago, Taranaki, Waikato, and Wairarapa regions of New Zealand. An ELISA was used to measure antibodies to E. rhusiopathiae. Samples with an optical density reading ≥1.50 were considered to be positive. Logistic regression analysis was used to model the effect of housing type, geographical location and flock age on the prevalence of samples positive for antibodies to E. rhusiopathiae.

RESULTS: The overall prevalence of samples with antibodies to E. rhusiopathiae was 39.8 (95% CI=35.68–44.06)% for the 545 samples, and 46/55 (84%) farms that were tested had at least one positive sample. Mean seroprevalence for types of housing was 44.2 (95% CI=37.79–50.70)% for free-range (n=240 birds), 23.7 (95% CI=17.83–30.38)% for shed (n=190), 73 (95% CI=56–86)% for caged (n=37) and 50 (95% CI=38–62)% for unknown (n=78). The disease was present in all seven geographical locations from which samples were obtained for this study. Seroprevalence increased with increasing age of birds (p<0.001); for birds ≤12 weeks of age it was 2 (95% CI=0.3–8)% (n=91), 13–24 weeks 29.1 (95% CI=23.34–35.46)% (n=230), 25–36 weeks 47 (95% CI=32–64)% (n=40), 37–48 weeks 75 (95% CI=51–91)% (n=20), >48 weeks 63.8 (95% CI=54.78–72.12)% (n=127). Neither housing type nor geographical location had a significant effect on the likelihood of samples being positive for antibodies to E. rhusiopathiae.

CONCLUSIONS: The results of this study suggest the prevalence of erysipelas under New Zealand field conditions may be higher than expected and that the disease is significantly associated with increasing age. Housing type and geographical location appear to be unrelated to seroprevalence.

CLINICAL RELEVANCE: Further study of the epidemiology of E. rhusiopathiae in chickens in New Zealand should be considered in order to minimise the extent of birds' exposure to the organism. These findings will assist in the design of further studies.  相似文献   

11.
Background: Besides the anticoccidial drug resistance problem, increasing consumer concerns about food safety and residues have propelled the quest for alternative prevention and control strategies amongst which phytotherapy has gained appeal due to a renewed interest in natural medicine.Objective: The objective was in vivo screening of four phytochemicals/extracts and a fungal immunomodulatory protein (FIP) against an Eimeria acervulina infection in broilers.Animals and methods: Four phytochemicals/extracts (extract from Echinacea purpurea, betaine (Betain?), curcumin, carvacrol (two different doses)), and a recombinant FIP from Ganoderma lucidum cloned and expressed in Escherichia coli were investigated for their anticoccidial potential. The experiment was conducted in a battery cage trial with 54 cages of eight birds each. Broilers infected with E. acervulina (a low and high infection dose of 104 and 105 sporulated oocysts, respectively) and treated with the phytochemicals/extracts or the FIP were compared with broilers treated with the anticoccidial salinomycin sodium (Sacox®) and with an untreated uninfected and an untreated infected control group. Coccidiosis lesion scores, body weight gains and oocyst shedding were used as parameters.Results: The results showed a coccidiosis infection dose effect on the mean coccidiosis lesion scores. The phytochemicals/extracts and the FIP failed to reduce coccidiosis lesion scores and oocyst shedding, while salinomycin efficiently controlled the E. acervulina infection and enabled significantly higher body weight gains.Conclusion: In conclusion, the selected phytochemicals/extracts and the FIP did not reduce the lesions of an experimentally induced E. acervulina infection.  相似文献   

12.
An observational study was conducted to determine the prevalence of Isospora suis oocysts in fecal samples from suckling piglets in Ontario, and to evaluate the relationship between the presence of I. suis oocysts and diarrhea. Fifty farms and 709 litters of piglets were included in the study. Oocysts were detected on 70% of farms, with 187 litters infected. A litter of pigs that was positive for oocysts was significantly more likely to exhibit diarrhea than a litter that was negative [odds ratio (OR) = 4.0; 95% confidence interval (CI) = 2.8 to 5.8; P < 0.001]. Management and housing factors were examined with respect to risk factors for the presence of I. suis. Farms that did not use a detergent when cleaning farrowing crates were 10-times more likely to be positive for I. suis than those that used a detergent (P = 0.007). It was concluded that coccidiosis is a common problem on Ontario swine farms.  相似文献   

13.
为了筛选有效的球虫消毒剂,本研究将柔嫩艾美耳球虫卵囊分别与16种常用消毒剂和1种高效抗球虫药物溶液（250 mg/L妥曲珠利溶液）混合作用2 h然后在2.5%重铬酸钾溶液中孢子化培养,或混合作用4 h后接种14日龄雏鸡,根据卵囊孢子化率、孢子化抑制率、每克粪便卵囊数量（oocysts per gram of feces,OPG）、病变计分和血便情况评价消毒剂和抗球虫药物抑杀球虫卵囊效果。结果显示,8%氨水对未孢子化卵囊和孢子化卵囊均表现为100%的抑杀效果;250 mg/L妥曲珠利、3%甲醛、4%苯酚、0.5%过氧乙酸、5% NaOH+10% NaCl和5% NaOH对球虫卵囊活性具有一定的抑制作用,孢子化抑制率超过10%,但是对孢子化卵囊抑杀作用不明显;而剩余10种常用消毒剂对球虫卵囊没有明显的抑杀作用。氨水抑杀球虫卵囊条件优化的试验结果显示,1%~8%氨水与未孢子化卵囊作用1 h以上,均可100%抑杀球虫卵囊活性。粪便干扰试验结果显示,粪便不影响2%和4%氨水对球虫卵囊的抑杀效果。本研究结果说明常用消毒剂和抗球虫药物不能有效杀灭球虫卵囊的活性,而氨水是一种高效球虫消毒剂。本研究结果可为开发新型高效球虫消毒剂和球虫病控制提供参考。  相似文献   

14.
Control of Isospora suis-induced coccidiosis on a swine farm   总被引：6，自引：0，他引：6  
Results of a program designed to control neonatal porcine coccidiosis on a total confinement, farrow-to-finish swine farm are reported. The control program consisted of washing, phenol disinfection, and steam cleaning of farrowing houses and treatment of sows with amprolium HCl before and after farrowing. Before initiation of the control program, 88.9% of the sows examined in the farrowing house were negative for coccidian oocysts, 9.9% were positive for Eimeria spp, and 1.2% were positive for Isospora suis. Most pigs nursing on sows before initiation of the control program had diarrhea at 5 to 10 days of age, which led to dehydration and weight loss. Morbidity was high, and mortality was moderate. Composite fecal samples from these litters were all positive (100%) for I suis. After initiation of the control program, 99.6% of the sows examined in the farrowing house were negative for coccidian oocysts and 0.4% were positive for Eimeria spp. Clinical signs of coccidiosis were rarely present in nursing pigs examined after the control program was initiated; however, I suis was still present in 19.8% of the composite fecal samples from pigs examined. An association between oocyst production in sows and I suis infections in pigs was not found in the present study. Oocysts of Eimeria spp were not found in the feces from the pigs.  相似文献   

15.
Background

Toxoplasma gondii is a common protozoan parasite among all mammals, in particular small ruminants, worldwide. Traditional husbandry can be a major risk factor for infection of sheep and goats with this parasite.

Objectives

The present study aimed to determine the current status of the prevalence for T. gondii in livestock of Qazvin Province.

Methods

In this cross-sectional study, the sera of 455 sheep and 375 goats were examined to detect anti-Toxoplasma IgG antibodies by using in-house indirect ELISA.

Results

Overall, 33.62% (153/455) of sheep and 36.41% (130/375) of goats were positive for anti-Toxoplasma IgG antibodies with no statistically significant difference. The prevalence rate of T. gondii among the sheep of Qazvin County was significantly higher than in Abyek and Abhar counties (p < 0.001).

Conclusions

The results of the present study indicate that the prevalence of T. gondii in sheep and goats of the study area is high. Therefore, the meat of the animals reared in this area can be a potential source of human infections by this parasite.

  相似文献   

16.
Abstract

Factors influencing rate of barren ewes, number of lambs born per pregnant ewe, and autumn live weight of the lambs were studied in 627 Norwegian sheep flocks based on herd level data from the Norwegian Sheep Recording System and a mailed questionnaire to the sheep farmers. The following factors were significantly associated (P<0.05) with rate of barren ewes: breed, herd average lambing date, type of production/age of farmer, routines for treatments for parasites, and housing type. Number of lambs born per pregnant ewe was significantly associated with rate of barren ewes, herd average lambing date, breed, percentage grass silage of total roughage, and no separation of gimmers during the housing period. Corrected autumn live weight of the lambs was significantly associated with breed, flock size, lambs born per pregnant ewe, no separation of gimmers during the housing period, and type of summer pasture.  相似文献   

17.
Hereford calves, seven months old, were inoculated orally with sporulated oocysts of Eimeria bovis and E. zurnii and housed in a heated building together with uninoculated animals. Duplicate groups of similarly treated animals were left unsheltered in cold winter weather. Clinical coccidiosis developed in most of the inoculated calves, sheltered and unsheltered. There was no marked difference in the severity of the infections. The sheltered uninoculated contact animals remained clinically unaffected, but mild coccidiosis developed in the unsheltered controls.

The results suggest that cold may increase the host's susceptibility to clinical coccidiosis, but may not increase the severity of the signs once the clinical infection is established.

  相似文献   

18.
Abstract

AIM: To determine the prevalence of Mycobacterium avium subsp. paratuberculosis (Map) infection in wildlife, in pastoral landscapes with a recent history of clinical Johne's disease in livestock.

METHODS: A total of 449 wild mammals and birds from three farms in the South Island of New Zealand with recent histories of clinical Johne's disease in their deer herds were trapped and examined for gross pathological changes in the gastrointestinal tract. Additionally, individual mesenteric lymph nodes from 380 mammals, and segments of gastrointestinal tract from 32 birds were excised, homogenised and cultured for viable Map bacilli. The prevalence of Map infection was then calculated for the various species. Faecal samples from those mammals which had culture-positive tissues were further cultured for the presence of Map.

RESULTS: Gross pathological changes were identified in the gastrointestinal tract of four brushtail possums, one cat, six ferrets, 12 hares, six hedgehogs, three rabbits, one stoat, and one paradise shelduck. Infection with Map in the gastrointestinal tract was confirmed in only three of these cases, one each of brushtail possums, hares and hedgehogs. In contrast, Map infection in the absence of gross pathological changes was frequently recorded in enteric tract tissues of mammals and birds. Among mammals, Map infection was recorded in 18/73 (25%) brushtail possums, 4/23 (17%) cats, 15/42 (36%) hedgehogs and 29/113 (26%) rabbits. Among birds, intestinal tract tissue Map infection was recorded in 3/17 (18%) paradise shelducks. Among 64 of the 74 mammals which had Map culture-positive tissues, 38% (n=5) of hedgehogs and 11% (n=3) of rabbits also had culture-positive faecal samples.

CONCLUSIONS: This study is the first to identify that Map infection can be prevalent in wildlife in New Zealand. There was a high prevalence of Map infection among both scavenging and grazing wild animals. Both mammals and birds are capable of harbouring viable Map organisms in their gastrointestinal tract; further, viable Map was excreted into the environment via faeces by hedgehogs and rabbits.

CLINICAL RELEVANCE: Previous studies overseas have postulated a role of wildlife as reservoirs of Map infection and possible vectors of Johne's disease to livestock. Here, brushtail possums, hedgehogs and rabbits and in particular were identified as potential wildlife hosts for Map infection in NewZealand. This suggests that several wildlife species could contribute to the persistence of Map infection within a wildlife/livestock complex, and potentially, perhaps more importantly, to the spread of infection between farms.  相似文献   

19.
Faecal samples from 232 domestic pigs raised on concrete, 98 free-ranging village pigs, and five wild boar showed 46.6 (108/232), 54 (53/98) and 80% (4/5) prevalence of coccidian oocysts, respectively. Eight species of Eimeria, and Isospora suis, were recovered. In their descending order of predominance in the pigs raised on concrete, the species of coccidia were E. debliecki (26.7%), E. scabra (22.4%), E. neodebliecki (19.8%), E. porci (15.5%), E. suis (11.6%), E. polita (8.6%), E. perminuta (7%), E. spinosa (5.6%) and I. suis (3.9%). The first five species listed above predominated in the village pigs as well. E. polita, E. spinosa and I. suis were not found in the wild boar. I. suis oocysts prevailed in 8.3% of the 36 sows on concrete, and in 11.1% (3/27) of those which were positive for coccidia. Isosporoid oocysts were absent in the village sows. Of the 125 less than 24-day-old piglets, 29.6% were diarrhoeic, and of these, 43.2% were positive for coccidia. Four of the 16 (25%) coccidia-positive, diarrhoeic piglets, and four of the 37 (10.8%) coccidia-positive non-diarrhoeic piglets shed I. suis oocysts, an observation which seems to weaken the present contention that I. suis is the primary causative agent of neonatal porcine coccidiosis. The highest mean number of oocysts per gram faeces (23,550) was recorded from the diarrhoeic farm piglets on concrete, and the lowest of 6,100 from the gestating farm sows. Mean opg data revealed very little significant quantitative variation between the corresponding age groups of the free-ranging village pigs and the commercially-farmed ones. One of the most interesting findings in the study was that the sows were more frequently infected than all other age groups.  相似文献   

20.
Coccidiosis is a disease of almost universal importance in Poultry production. The subclinical form of coccidiosis has most significant economic impact due to impaired growth rate and feed conversion. Some factors such as: age, size of flock, season, etc., may effect on severity of this disease. In this study, the relationships between some major risk factors and prevalence of subclinical coccidiosis were investigated. This study was done in 120 broiler farms in five different cities of Mazandaran province, north of Iran. Five chicks (3–8 weeks of ages) were taken randomly from every 120 farms and post-mortem and parasitological examinations were performed. Five Eimeria spp. were recognized: Eimeria tenella, Eimeria maxima, Eimeria acervulina, Eimeria brunetti, and Eimeria necatrix. The prevalence rate of subclinical coccidiosis among them is 75% (90 farms out of 120). E. acervulina was the most prevalent species (65.5%) followed by E. maxima (17.7%), E. tenella (15.5%), E. brunetti (10%), and E. necatrix (5.5%). According to what the results approve, the occurrence of subclinical coccidiosis is significantly related to the age and size of flock, whereas the other factors such as the season of year, industrial strains, chicken’s keeping system, and anticoccidial drugs do not affect this phenomenon remarkably.  相似文献   

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