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1.
The effect of Mycoplasma gallinarum isolated from village chickens on embryonated village chicken eggs was investigated. Seven-, 10−, 12− and 18-day-old embryos were inoculated with medium containing 106 colony forming units of M gallinarum or with uninfected medium and incubated at 37°C until they hatched. There was no significant difference between the infected embryos which failed to hatch and those which hatched or between them and the group inoculated with medium only. A much higher percentage of the eggs inoculated as 18-day-old embryos hatched than of those inoculated at seven, 10 and 12 days old. The hatchability of the uninoculated village chicken eggs used in the four trials ranged from 60 to 100 per cent. Mycoplasmas were isolated from the oesophagus, trachea and yolk of the infected chicks and from the dead-in-shell embryos.  相似文献   

2.
The present study was conducted to evaluate the adverse effects of an interaction between low levels of dietary aflatoxins (AF) and Eimeria tenella infection on broiler chicks. A set of 1-day-old chicks were raised for 35 days in the following groups: a control group, a group fed AF, a group fed AF and inoculated with E. tenella (AF + E.ten), and a group inoculated with E. tenella alone. AF in the contaminated diet were given at 200 ppb starting from the seventh day after hatching while E. tenella was inoculated at a dose of 5 × 104 sporulated oocysts per chick at the 14th day after hatching. Worsened performance traits and high mortality were all observed in the treated birds, particularly the AF + E.ten group. Lesion scores and oocyst outputs were not different within groups. Chickens fed with AF had significantly increased serum ALT and ALP activities as well as decreased albumin content. They also showed hepatomegaly, hepatocytic vacuolation and necrosis, an atrophied bursa of Fabricius, and a thymus with tissue depletion. E. tenella-infected broilers displayed a significant reduction in packed cell volume, hemoglobin content and lymphocyte percentage, and showed hemorrhagic typhlitis. The deficits in hepatic function and hematologic parameters as well as the gross pathological, and histopathological changes, were more common and more severe in the group that was exposed to both aflatoxicosis and coccidiosis than in the groups exposed to either treatment alone. Thus, the combination of aflatoxicosis and E. tenella infection may influence the course of coccidial infection due to additive effects.  相似文献   

3.
The effect on the growth of Salmonella infantis in the caeca of chicks pre‐treated with either the cultured flora of the alimentary tract of an adult chicken, horse faeces or bovine rumen fluid was studied. Forty 2‐d‐old chicks were inoculated orally with S. infantis. Pre‐treatment with the cultured flora of the alimentary tract of an adult chicken as well as fluids from the alimentary tract prevented the colonisation of the caeca by S. infantis. The numbers of salmonella isolated from the caeca of all chicks with no pre‐treatment were more than 107 per g. Bovine rumen fluid and horse faeces were ineffective in preventing the caeca of chicks being colonised by S. infantis.  相似文献   

4.
In our continuing effort to generate transgenic chickens, sonoporation was chosen to insert an exogenous gene into the chicken genome. An EGFP expression vector (pCAG‐EGFPac) and microbubbles were injected into the central disc of stage‐X blastoderm or the germinal crescent of stage‐4 embryos, followed by ultrasonic vibration. Nineteen chicks out of 108 treated embryos hatched, six females and six males out of these 19 chicks grew to sexual maturity and two females and three males lived for 3 years. Genomic DNA from 17 out of 35 gonads from embryos and chicks that died before sexual maturity was EGFP‐positive by PCR. No EGFP sequence was detected in the genomic DNA of 322 embryos from six sexually mature females and the semen from four sexually mature males by PCR. When genomic DNA was obtained from various tissues of five 3‐year‐old chickens, the EGFP sequence was amplified from the genomic DNA of the breast muscle of a female (No. 85). The above sequence was subjected to DNA sequencing and verified to be the EGFP sequence. These results showed that sonoporation is an effective tool for the transduction of exogenous genes into chicken embryos for the generation of transgenic chickens.  相似文献   

5.
Quail (Coturnix coturnix japonica) and broiler (Gallus domesticus) chicks were inoculated experimentally with IBH virus (avian adenovirus-1) derived from quails to determine its pathogenicity. Quail chicks were inoculated by the intraperitoneal route at 3, 4, 5, 6 or 7 weeks of age. Lesions were encountered most frequently in the liver, kidneys and lungs. These included pale, swollen and mottled liver, swollen nephrotic kidneys, and congested and pneumonic lungs. The lesions were severe in birds inoculated at 5 weeks of age. Large basophilic intranuclear inclusion bodies were seen in hepatocytes and occasionally in the renal epithelium. The results showed that this isolate is pathogenic for quails above 3 weeks of age. Broiler chicks were inoculated at 4 weeks of age by the intraperitoneal route. The lesions produced in these chicks were similar to those of adenovirus-induced inclusion body hepatitis. Viral antigen was also demonstrated by dot-ELISA in suspensions of liver tissue from both quail and broiler chicks.Abbreviations AAF amnio-allantoic fluid - AAV avian adenovirus - DPI days post inoculation - EID50 dose infective for 50% of embryos - ELISA enzyme-linked immunosorbent assay - IBH inclusion body hepatitis - INIBs intranuclear inclusion bodies - NAF normal allantoic fluid  相似文献   

6.
Summary A total of 1024 enterococci were recovered from faeces of healthy animals from 178 cattle, 178 pig and 156 broiler farms. Enterococcus faecium was the predominant species recovered (35.8%), followed by E. faecalis (31.3%) and E. hirae (25.6%). Oxytetracycline resistance was most frequently found among E. faecalis (85.9%), E. faecium (58.8%) and E. hirae (48.1%). Resistance rates to almost all antimicrobials were higher in E. faecalis than E. faecium and E. hirae. Isolates from cattle were more susceptible to the antimicrobials studied than those from pigs and broilers. VanA‐ or VanB‐type vancomycin‐resistant enterococci have not been found since the ban of avoparcin use 5 years ago.  相似文献   

7.
Day-old broiler chicks, which had been shown to be negative for maternal antibodies against inclusion body hepatitis (IBH) virus and for viral antigen in cloacal swabs, were divided into four groups of 20 chicks each. One group was fed ochratoxin-A at 0.5 ppm from 3 to 38 days of age, another group was inoculated with 1 ml of IBH virus containing 106.5 EID50 per 0.2 ml. A third group was given both ochratoxin-A and infected with IBH virus. The fourth group served as the control. Anaemia was observed in all three treated groups but the changes were more pronounced in the combined group. The biochemical changes also suggested a cumulative damaging effect by ochratoxin-A and IBH virus.  相似文献   

8.
Two trials were made to assess the efficacy of including calcium fosfomycin in the drinking water or in the feed for four days to control the adverse effects of experimentally induced colibacillosis in broiler chickens. Trial 1 had five groups of 15 chicks each: one group of negative controls; an untreated infected control group and three groups treated with 50, 100 or 200 ppm of calcium fosfomycin in drinking water. Trial 2 had the same groups but the antibiotic was incorporated into the feed. The chickens were infected via their air sacs with 1.7 x 108–3.6 x 108 CFU/chick of Escherichia coli O78:K80. The morbidity and mortality, a score for the gross lesions, the relative weight of the liver and spleen, performance and re-isolation of the challenge bacteria were recorded. Calcium fosfomycin in the drinking water controlled the colibacillosis, particularly in the group treated with 200 ppm. However, no effect of the antibiotic was seen when calcium fosfomycin was incorporated into the feed, the mortality, score of lesions and re-isolation of E. coli from the organs in the three treated groups being similar to those for the infected unmedicated group. The amount of antibiotic ingested in trial 1 was three times more than in trial 2. These results suggest that calcium fosfomycin is best used in the drinking water for the treatment of colibacillosis.  相似文献   

9.
Broiler chicks were fed on a high energy, commercial‐type ration with 20 g oxycarotenoids/ton1 for 5 weeks. They were then transferred to two finisher rations: one with 20 g oxycarotenoids from the ingredients plus 3 g canthaxanthin/ton; the other containing 26 g oxycarotenoids/ton derived solely from the ingredients. Three replicated groups fed on each finisher ration were inoculated daily for 5 d with either 6000 sporulated oocysts of E. maxima, 30,000 sporulated oocysts of E. acervulina or no coccidial oocysts. The resultant mild infections caused reduced growth and impaired food conversion irrespective of the ration fed. Pigmentation, based on shank visual scores, plasma and toe‐web total carotenoid concentrations, was adversely affected in all infected groups. Groups fed canthaxanthin had higher visual scores than comparable groups not so supplemented; however, the presence of coccidiosis depressed flesh pigmentation proportionately in both groups judged by several pigmentation parameters. E. acervulina infection was as deleterious to the broiler as E. maxima, based on these criteria.  相似文献   

10.
A study was undertaken to investigate the role of in ovo administrated carbohydrates on the expression pattern of growth and immune‐related genes. In ovo injections (n = 400) were carried out on the 14th day of incubation into the yolk sac/amnion of the broiler chicken embryos. Expression of growth‐related genes: chicken growth hormone (cGH), insulin‐like growth factor‐I & II (IGF‐I & II) and mucin were studied in hepatic and jejunum tissues of late‐term embryo and early post‐hatch chicks. Expression of candidate immune genes: Interleukin‐2, 6, 10 and 12 (IL‐2, IL‐6, IL‐10 and IL‐12), Tumour necrosis factor‐alpha (TNF‐α) and Interferon gamma (IFN‐γ) were studied in peripheral blood monocyte cells of in ovo‐injected and control birds following antigenic stimulation with sheep RBC (SRBC) or mitogen concanavalin A (Con‐A). Glucose injection significantly increased the expression of IGF‐II gene during embryonic period and both cGH and IGF‐II in early post‐hatch period, while ribose‐injected chicks had higher expression of IGF‐II gene during embryonic stage. Enhanced mucin gene expression was also observed in fructose‐injected chicks during embryonic age. Glucose‐injected chicks had higher expression of IL‐6 or IL‐10, while those injected with fructose or ribose had higher expression of IL‐2, IL‐12 and IFN gamma. It is concluded that in ovo supplementation of carbohydrates might help in improving the growth of late‐term embryos and chicks. In ovo glucose could modulate humoral‐related immunity, while fructose or ribose might help in improving the cellular immunity in broiler chickens.  相似文献   

11.
Introduction and purposeDespite the various vaccination programs for protection against New Castle disease, it remains an important threat to the poultry industry. The ability of the probiotic bacteria to improve the immune system in both animals and humans supports their use as immune adjuvants for vaccination. The aim of the present study was to examine the effects of Lactobacillus acidophilus in ND vaccination.Materials and methodsA total of 170 one day old chicks were divided in 5 groups. In groups A, B and C chicks were received L. acidophilus (5 × 109, 3 × 109 and 2 × 109) and also vaccinated with inactivated and attenuated ND vaccines. In group D, chicks only vaccinated without bacterial inoculation and group E was negative control with neither vaccine nor bacteria. Then IgG and HI NDV antibody titers were measured in all tested groups.ResultsIgG and HI NDV antibody levels were significantly higher in Lactobacillus treated groups especially in group A with 5 × 109 bacteria, than only vaccinated and negative control groups. Also antibody levels against NDV increased during the vaccination period especially in probiotic treated groups.ConclusionIn conclusion, L. acidophilus can use for improving immunogenicity of NDV vaccination programs.  相似文献   

12.
Oligodeoxynucleotides (ODN) containing cytosine-phosphodiester-guanine (CpG) motifs have been shown to be effective immunoprotective agents in murine models for a variety of viral, intracellular bacterial, and protozoan infections. We recently have shown that CpG ODN protects against extracellular bacterial infections in mature chickens. The objective of this study was to investigate the effect of CpG ODN on Escherichia coli septicemia in neonatal broiler chicks. Two-day-old chicks, or embryonated eggs that had been incubated for 18 or 19 days, received 50 microg CpG ODN. Three days after exposure to CpG ODN, a virulent isolate of E. coli was inoculated subcutaneously in the neck of each bird. Birds were examined for 7 days post-E. coli challenge and dinical, pathologic, and bacteriologic assessments were conducted. The control group of birds that received no CpG ODN had a survival rate of 0% to 20%. In contrast, groups that received CpG ODN, either by intramuscular or in ovo routes, had significantly higher survival rates (P < 0.0001). Bacterial counts in air sacs were significantly lower when birds or embryos were treated with CpG ODN as compared with controls. A dose as low as 10 microg of CpG ODN, administered intramuscularly, was able to protect birds significantly against E. coli challenge. Formulation of CpG ODN with 30% Emulsigen did not enhance the protection. This study demonstrates that CpG ODN has systemic protective effects in broiler chicks against E. coli infections. This is the first time that CpG ODN has been demonstrated to have an immunoprotective effect against a bacterial infection in chicks following in ovo delivery.  相似文献   

13.
1. The effect of butyric acid glycerides (BAGs) with and without clopidol (CLP) on Eimeria maxima on growth and associated biochemical variables was investigated in broiler chickens.

2. One-day-old chicks were divided into 6 equal groups (Gps) of 30 chicks each; each group was subdivided into 6 equal subgroups. Gp 1 was not infected and not treated. Chicks in Gp 2 were not infected and fed on a ration mixed with 4 g BAGs/kg for 6 successive weeks. Chicks of the other groups were directly inoculated intra-crop with 1 × 104 sporulated oocysts of E. maxima at 14 d of age. Gp 3 was infected and not treated. Chicks in the remaining three groups were given diets mixed with the tested drugs for 6 successive weeks. Gp 4 was fed on a diet mixed with CLP (125 g/kg). Gp 5 was given a diet mixed with BAGs (4 g/kg diet). Gp 6 was fed on a diet mixed with both BAGs (4 g/kg diet) and CLP (125 g/kg).

3. Birds in Gps 5 and 6 showed a reduction in the mean oocyst count, lesion scores and developmental stages in the lamina propria and improved growth and biochemical variables. BAG supplementation enhanced growth and production of healthy broilers.

4. It was concluded that BAGs were a useful supplement in broiler diets as an alternative to growth promoters and antimicrobial drugs.  相似文献   


14.
AIM: To examine the infective dose, incubation period and disease progression of an isolate of Salmonella enterica serotype Typhimurium definitive type 160 (DT160) originating from a naturally-infected house sparrow (Passer domesticus) during an outbreak of the disease in New Zealand.

METHODS: Thirty-six house sparrows captured from the wild and free of Salmonella spp were divided into six groups of six birds, housed individually, and inoculated orally with phosphate buffered saline (PBS) or 101, 102, 103, 105, 2 × 108 colony forming units (cfu) of the outbreak strain of S. Typhimurium DT160. The birds were observed for 10 days for clinical signs and/or mortality, and faecal samples were collected to determine excretion of S. Typhimurium. The birds were eutha- nised 11 days post-inoculation (p.i.) and a wide range of tissue samples were collected for histopathological examination, and culture and typing of Salmonella spp. Macro-restriction profiling by pulsed-field gel electrophoresis (PFGE) using XbaI was performed for the epidemiological typing of S. Typhimurium DT160 isolates.

RESULTS: Mortality in house sparrows inoculated with S. Typhimurium DT160 was dose-dependent, and 2/6 birds inoculated with 105 cfu and all six birds inoculated with 2 × 108 cfu died during the study. Infected sparrows displayed few clinical signs, apart from diarrhoea and/or polyuria, fluffed plumage, and sitting on the floor of the cage. Faecal excretion of DT160 occurred briefly in two birds inoculated with 102 cfu and four birds inoculated with 103 cfu, on most days in five birds inoculated with 105 cfu, and continuously in six birds inoculated with 2 × 108 cfu. DT160 was isolated from the livers of three birds which received 103 cfu, five birds dosed with 105 cfu, and all six birds given 2 × 108 cfu. Following necropsy, histopathological lesions similar to those seen in the natural disease were observed in the liver or spleen of three birds which received 103 cfu, and all birds dosed with ≥105 cfu.

CONCLUSION: The results indicate that an isolate of S. Typhimurium DT60 originating from house sparrows in New Zealand is pathogenic to these birds and that the response is dose- dependent. The persistence and excretion of the pathogen may last for at least 10 days. This confirms that sparrows infected with DT160 could be a source of infection to humans and other in-contact animals.  相似文献   

15.
The effect of the enterocin A-producing EK strain of Enterococcus faecium on Salmonella dusseldorf SA31 was tested in gnotobiotic Japanese quails. Sixteen 3-day-old gnotobiotic Japanese quails, hatched from disinfected eggs placed in sterile boxes, were divided into two groups of 8 birds: a control group, which was inoculated orally with the SA31 strain (1×107 CFU/ml), and the experimental group, which was inoculated orally with 200 l of E. faecium (1×109 CFU/ml), 16 h before infection with the S. dusseldorf. The latter group then received the same average dose of E. faecium daily in drinking water. Faecal samples were taken 8, 24, 48 and 168 h after the inoculation of S. dusseldorf and examined for S. dusseldorf and E. faecium (EK13). The quails were then killed and the number of the EK13 strain of E. faecium and of S. dusseldorf in the caecum and ileum were estimated. A reducing effect of the EK13 strain against the SA31 strain in faeces was detected in the samples taken at 24 and 48 h from the group with the EK13 strain. Significant reductions were also found in the numbers of S. dusseldorf SA31 strain in the caecum but not in the ileum.  相似文献   

16.
为筛选出理想的鸡白痢沙门氏菌宿主感染模型的建立方法,本研究通过选择不同接种方式配合不同菌液浓度接种不同胚龄鸡胚建立感染模型,将90枚SPF鸡胚随机分成9组,每组10枚,分别为A、B、C、D、E、F、G、H、I组,A组为空白对照组,其余各组为模型组,模型组分别以气室接种、蛋壳接触接种的方式对不同胚龄（11和14胚龄）SPF鸡胚接种不同浓度（1×103、3×103、9×103、3×105、9×105 CFU/mL）的鸡白痢沙门氏菌C79-3菌株。每天观察情况直至出雏,待雏鸡孵出后按组分笼饲养,每隔12 h观察1次,连续观察7 d,观察各组雏鸡的临床症状、死亡情况,观察期结束对死亡和存活雏鸡进行剖检、组织病理学检查及鸡白痢沙门氏菌的分离鉴定。结果显示,各模型组均有雏鸡出现明显的鸡白痢病症状并死亡,相较于其他模型组,以11胚龄蛋壳接触感染方式接种9×105 CFU/mL的C79-3菌液的F组和14胚龄气室感染方式接种3×103 CFU/mL C79-3菌液0.1 mL的H组,鸡胚出壳率较高,可分别达到80%和90%,出壳雏鸡呈现明显鸡白痢病特征,剖检可见肝脏出血、盲肠膨大、卵黄囊吸收不良;组织病理切片可观察到肝脏、盲肠、心脏各有不同程度的损伤,发病率分别100%和88.8%,并且鸡白痢沙门氏菌阳性检出率分别达70%和90%。本研究结果表明,以11胚龄蛋壳接触感染方式接种0.1 mL 9×105 CFU/mL的C79-3菌液和14胚龄以气室感染方式接种0.1 mL 3×103 CFU/mL的C79-3菌液的两种方法均可用于建立稳定的鸡白痢沙门氏菌宿主感染模型。  相似文献   

17.
This investigation was designed to characterise the specific cytokine activity from the conditioned medium of concanavalin A-stimulated avian T cells derived from Salmonella enteritidis-immune chickens, S enteritidis-immune lymphokine (ILK). Studies were designed to determine first, whether colony-stimulating activity was present in ILK, second, the type(s) of colonies from the bone marrow that were supported in vitro by the potential colony-stimulating factors in ILK and, third, whether colony-stimulating activity was present in serum from chicks treated with ILK and challenged with S enteritidis, and to use physicochemical treatment as a means of identifying the potential colony-stimulating factor(s) in ILK. Both ILK alone and serum from chicks treated with ILK and challenged with S enteritidis caused significant increases in the number of colony-forming units (CFU) from the bone marrow in vitro. After 10 days of incubation, ILK alone supported the in vitro growth of granulocytic bone marrow colonies. The colony-stimulating activity from serum derived from chicks treated with ILK and challenged with S enteritidis peaked two hours after the challenge. When ILK was either heated at 100°C or treated with trypsin or acid and then injected into chicks, all the chicks responded with significant increases in circulating polymorphonuclear leucocytes (PMNS). However, when assayed for in vitro colony-stimulating activity, only trypsinisation destroyed the activity in ILK. The results indicate that a colony-stimulating factor which preferentially supported the growth of granulocytic bone marrow colonies was present in ILK and that the factor was stable to heat and acid but sensitive to trypsin.  相似文献   

18.
This study aimed to investigate the potential toxic effects of pure glyphosate or Roundup® on hatchability, serum biochemistry and histopathological observation of the liver and kidney of newly hatched chicks. On day six, a total of 225 fertile eggs were obtained from Huafeng breeder hens. The eggs were randomly divided into three treatments: (a) the control group injected with deionized water, (b) the glyphosate group injected 10 mg pure glyphosate/Kg egg mass and (c) the Roundup group injected 10 mg the active ingredient glyphosate in Roundup®/Kg egg. The results showed a decrease of hatchability rate in chicks treated with Roundup® (66%). In addition, no significant change was observed in body weights, yolk sac weight and relative weight organs except the liver and kidney were significantly increased with groups treated with glyphosate and Roundup® compared to the control group. The results showed that serum protein profiles were linearly significantly increased of serum phosphor, uric acid, aspirate aminotransferase, alanine transaminase and alkaline phosphatase in groups treated with Roundup®, as well as the serum concentrations of triglyceride altered after treatment with glyphosate. Furthermore, oxidative stress was observed in the treated chicks, the glyphosate and Roundup® induced changes of the content of malondialdehyde in both the liver and kidney, moreover decrease of glutathione peroxidase, total superoxide dismutase and catalase activity in the kidney tissue and serum. Additionally, changes also happened in the histomorphology of the liver and kidney tissue of the treated chicks. It can be concluded that Roundup® as a probable decrease of hatchability. Exposure to glyphosate alone or Roundup® caused liver and kidney histopathological alterations, serum parameters imbalances and oxidative stress, also induced a variety of liver and kidney biochemical alterations that might impair normal organ functioning in newly hatched chicks.  相似文献   

19.
Freshly excreted Canada goose faeces pose a public health risk as they contain pathogenic microorganisms. Accordingly, a study was carried out on the growth and survival of resident indicator bacteria (enterococci and Escherichia coli) and inoculated Campylobacter jejuni in freshly excreted faeces over summer and winter. Canada goose faeces were collected, mixed thoroughly and inoculated with 108 g?1C. jejuni. The faeces were mixed again before making the Canada goose dropping. The simulated goose droppings (N = 70) were placed on pasture, and the concentrations of E. coli, enterococci and the pathogen, C. jejuni, were monitored. In summer only, the molecular marker of E. coli LacZ and the avian‐associated bacteria E2 was also monitored. Results of the survival study indicated that significant growth of enterococci and E. coli occurred in summer, before concentrations decreased to less than 15% of the original concentration (day 77) for enterococci and 0.01% for E. coli. LacZ followed a similar pattern to E. coli, while the E2 marker dropped to below 0.1% of the original concentration within 4 days. In winter, enterococci grew slightly, while no growth of E. coli occurred. In both summer and winter, C. jejuni was rapidly inactivated. This research highlights the ability of bacterial indicators to replicate and survive in the environment when harboured by avian faeces, and the limited risk aged Canada goose faeces pose as an environmental source of Campylobacter spp.  相似文献   

20.
A study was conducted to evaluate the effects of ochratoxin A (OA) on Escherichia coli-challenged broiler chickens. Day-old broiler chicks were separated into two groups of 92 chicks each, with one group fed a control mash diet, and the other fed a mash diet containing 2 ppm OA. On day 14, each group was further separated into two groups, with one group inoculated with E. coli O78 (1 x 10(7) colony-forming units/0.5 ml), whereas the other group was not inoculated with E. coli. After E. coli inoculation on day 14, four birds from each group were euthanatized at 1, 2, 3, 5, 7, 10, 14, and 21 days postinoculation. Escherichia coli infection caused dullness, depression, huddling, and diarrhea. Mortality was 14.3% in chicks infected with E. coli but fed no OA. Mortality increased to 35.7% in chicks fed OA and infected with E. coli. Decreased body weight and reduced feed intake were observed in chicks fed OA, and the effects were more pronounced in chicks fed OA and infected with E. coli. Increased serum levels of aspartate aminotransferase, alanine aminotransferase, uric acid, and creatinine and decreased levels of total proteins, albumin, globulins, calcium, and phosphorus were observed in OA-fed birds. Escherichia coli infection did not cause significant alteration in any of the serum biochemical parameters. The presence of OA in poultry rations increased mortality and the severity of an E. coli infection.  相似文献   

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