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1.
In veterinary medicine plant based medicine is achieving a huge importance worldwide. This research was subjected to rectify the hydrophilic Moringa Oleifera alcoholic leaves extract could improve the immune system in vaccinated and non-vaccinated broiler Hubbard chickens experimentally exposed to Newcastle disease (ND) virus. Seventy five chicks with age one day old were splitted randomly into five groups equally in distribution with fifteen chick in each group. Group I was untreated unvaccinated (control negative group) while group IV was infected group with NDV (control positive group). The experimental Groups II and V were given daily oral treatment of hydrophilic alcoholic leaves extract of M. oleifera at 200 mg/kg body weight until day 21 of age while groups III and V were ND vaccinated with La Sota strain of ND vaccines. The four groups (II, III, IV, V) were infected with ND virus velogenic strain (VNDV) on day 21. Following to infection, Monitoring of birds were done daily for clinical signs, postmortem examination, morbidity and mortality. Cellular, humeral immune response and phagocytic activity were evaluated and the data were statistically analyzed using (SPSS). Total and differential cell numbers as well as Haemagglutination inhibition (HI) titre increased in the extract treated and vaccinated group which give total protection against NDV much more than treated and unvaccinated group. As a result it could be recommended to use M. Olifera extract from the first day of rearing in Hubbard chicken with ND vaccination program as a prophylactic treatment in protection of birds against ND infection.  相似文献   

2.
Abstract

We evaluated the role of some matrix metalloproteinases (MMPs) in enhancing the effect of vitamin A and the inhibiting effect of methylprednisolone on amyloid arthropathy in brown layer chicks. We used 100 one-day-old Isa brown layer chicks. The chicks were allocated to one of four groups as follows: negative control group (I), vitamin A group (II), positive control group (III) and methylprednisolone group (IV). Amyloid arthropathy was induced by injections of complete Freund's adjuvant into the left intertarsal joints of the chicks. Serum vitamin A and tissue MMP (MMP-1, MMP-2, MMP-9) levels were measured and differences among the groups were investigated. Serum vitamin A rates (μg/dl) were: 63.57 ± 4.10, 47.13 ± 10.62, 53.26 ± 10.79, 98.48 ± 8.20 in groups I, II, III and IV, respectively (p < 0.001). MMP-1, MMP-2 and MMP-9 levels were evaluated in tissues from the chickens with amyloid arthropathy. Methylprednisolone significantly suppressed the release of MMP-1 and MMP-2, and increased the release of MMP-9 in birds with amyloid arthropathy. In addition, vitamin A significantly increased the release of MMP-1, MMP-2 and MMP-9.  相似文献   

3.
Experiments were conducted to evaluate the effects of different competitive exclusion (CE) cultures on the concentration of cecal propionic acid in 3-day-old broiler chicks, and the correlation between cecal propionic acid concentration and protection againstSalmonellacolonization. CE cultures that significantly (P < 0.05) increased cecal propionic acid in 3-day-old chicks decreased (P < 0.05) cecalSalmonellacolonization in 10-day-old chicks compared with the untreated controls. CE cultures that failed to significantly (P > 0.05) increase cecal propionic acid concentrations in 3-day-old chicks failed to protect (P > 0.05) against cecalSalmonellacolonization in 10-day-old chicks compared with untreated controls. A significant (P < .05) correlation (−.88) was found between cecal propionic acid concentration in 3-day-old chicks and cecalSalmonellacolonization in 10-day-old chicks.  相似文献   

4.
The study was conducted to investigate the effects of different levels of eucalyptus powder (EP), virginiamycin and probiotic on performance, immunity, blood components and carcass traits of broiler chickens. A total of 250, 1-day-old male broiler chickens (Ross 308) were randomly allocated to five treatments with five replicates and 10 chicks each, as a completely randomized design. The dietary treatments consisted of: basal diet (BD), BD+0.25% EP, BD+0.5% EP, BD+0.01% of diet probiotic (Protexin), BD+0.02% of diet antibiotic (virginiamycin). Dietary supplementation did not affect feed intake, BW gain (BWG) and feed conversion ratio (FCR) during starter and grower phases, but BWG and FCR were affected during the finisher and whole periods (P<0.05).The highest BWG and lowest FCR were obtained in birds fed with virginiamycin and 0.5% EP. Dietary supplementation significantly increased the relative weight of carcass and breast (P<0.05). Treatments had no effect on relative weights of internal organs and small intestine except for bursa that increased by treatments. Relative length of jejunum also increased by treatments (P<0.05). Antibody production against sheep red blood cells did not changed in primary titer (day 35), but it significantly increased in secondary titer (day 42) by 0.5% EP. White blood cell counts were increased and cholesterol decreased by dietary supplementation (P<0.05). In conclusion, the results of this study showed that 0.5% EP served as a useful replacement for antibiotic and would improve performance and immune response of broiler chickens.  相似文献   

5.
Abstract

Sixty chickens were randomly divided into two groups (30 chickens in each group) to determine the effect of oral administration of chicken intestinal antimicrobial peptides (CIAMP) on the humoral immune response. Chickens of both groups were fed the same diet. In the treatment group chickens received drinking water supplemented with CIAMP (1 µg/ml) right after hatching. Samples of blood, bursa of Fabricus, spleen and intestine were taken at day 1, 4, 7, 10 and 17 of experiment. CIAMP supplementation enhanced the content of IgG and IgM in serum from day 4 – 10 and day 10 – 17, respectively, (p < 0.05), IgM-forming cells in bursa of Fabricus and spleen at the age of 7 days (p < 0.05) and IgG-forming cells in bursa of Fabricus at the age of 4 days (p < 0.05). In addition, CIAMP enhanced the IgA-forming cells in caecal tonsils diffuse area at day 4 (p < 0.05). Furthermore, CIAMP enhanced the antibody response to infectious bursal disease virus vaccine (IBDV) in chickens 21 days following IBDV vaccine administration (p < 0.05). These results suggested that CIAMP could modulate the humoral immune response of chickens and increased the antibody titres of infectious bursal disease virus vaccine.  相似文献   

6.
 A replication-deficient recombinant vaccinia virus, NYVAC, was developed by deleting 18 open reading frames in the vaccinia virus genome. Recombinant NYVAC, encoding the murine T cell co-stimulatory gene B7.1 (CD 80) (NYVAC-B7.1) and the murine interleukin-2 gene (NYVAC-IL-2), were prepared and the expression of B7.1 and the secretion of IL-2 were respectively confirmed in vitro. The use of these viruses to prepare a potent tumor cell vaccine was studied in a syngeneic murine CC-36 colon adenocarcinoma model. Mice were immunized on days 1 and 8 with 106 irradiated CC-36 cells that were infected with 107 plaque-forming units of either NYVAC-B7.1, NYVAC-IL-2 or a control virus, NYVAC-HR, which encodes a vaccinia virus host-range gene. These mice were then challenged with 108 viable CC-36 tumor cells on day 15. All mice (10/10) in a group that had received no vaccination and all mice (20/20) in a group that had received a control vaccine of CC-36/NYVAC-HR developed tumor 4-weeks after tumor cell challenge. Interestingly, only 16/20 mice in a group that had received CC-36/NYVAC-B7.1 showed the development of tumor after the same interval. The protection against tumor development and the reduction in tumor burden (as mean tumor diameter, 4 weeks after tumor challenge) were significant in this group when compared to groups that were either unvaccinated or vaccinated with CC-36/NYVAC-HR (mean tumor diameter = 6.51±3.2 mm compared to 26.5±0.9 mm or 26.2±1.8 mm respectively) (P = < 0.05). The protection against tumor in a group of mice that received CC-36/NYVAC-IL-2 vaccination was similar to that in the unvaccinated group or the group receiving a CC-36/NYVAC-HR control vaccination. However, in a survival experiment, mice that received either CC36/NYVAC-B7.1 or CC-36/NYVAC-IL-2 vaccination on the day of tumor transplantation survived significantly longer than mice that had not been vaccinated (median survival 60+ days, 60+ days or 23.5 days respectively) (P = <0.05). Interestingly, when a therapeutic tumor vaccination was performed on day 4 after tumor transplantation, mice that had been vaccinated with either CC36/NYVAC-B7.1 or CC-36/NYVAC-IL-2 did not show an improved survival when compared to mice in the control that had not been vaccinated (median survival 28 days compared to 26 days or 25 days respectively). However, mice that had received a therapeutic vaccination with CC-36 cells infected with both NYVAC-B7.1 and NYVAC-IL-2, 4 days after tumor transplantation, survived significantly longer than control mice that had not received any vaccination (median survival 29.5 days compared to 25 days respectively) (P<0.05). These results suggest that a replication-deficient recombinant NYVAC encoding the B7.1 gene and NYVAC encoding the IL-2 gene can be used to produce an effective vaccinia-virus-augmented tumor cell vaccine. Received: 2 March 1998 / Accepted 23 March 1998  相似文献   

7.
To understand the effectual role of COVID-19 vaccination, we must analyze its effectiveness in dampening the disease severity and death outcome in patients who acquire infection and require hospitalization. The goal of this study was to see if there was an association between disease progression in admitted COVID-19 patients and their prior vaccination exposure. A prospective cohort study based on 1640 admitted COVID-19 patients were carried between June 2021 and October 2021. Depending on vaccination exposure they were divided into vaccinated (exposed) and unvaccinated (unexposed) groups, excluding partially vaccinated patients. Disease severity was assessed at admission on severity index scale. Disease progression to mortality or need of mechanical ventilation and survival were taken as outcome. Absolute difference with 95%CI and Risk Ratio were calculated using cross tabulation, Chi square test and multivariable logistic regression analysis. Among 1514 total analyzed cohort (median age, 53 years [IQR, 17,106]; 43.7% from 46 to 65 years of age group, 56.2% males,33.4% with no comorbid factor for disease progression) 369(24.4%) were vaccinated breakthrough cases and 1145(75.6%) were unvaccinated controls. 556(36.7%) progressed to death or mechanical ventilation, 958(63.3%) patients survived and were discharged home. Disease progression to death or mechanical ventilation was significantly associated with decreased likelihood of vaccination (24.9% among vaccinated breakthrough vs 40.5% unvaccinated controls, [Absolute difference ?15.6% 95%CI (?10.2% to ?20.6%); RR 0.615 95%CI (0.509, 0.744); p <.001]). This association was stronger for old age population and for increase time span between second dose of vaccine and onset of symptoms. There was no statistically significant difference among different types of vaccination and occurrence of outcome when compared to unvaccinated controls (RR 0.607(0.482, 0.763); 0.673(0.339, 1.33) and 0.623(0.441, 0.881) for Inactivated virus vaccine, mRNA and Adenovirus vector-based vaccine respectively. The patients who were fully vaccinated against SARS-COV-2 die or shift to mechanical ventilation less frequently than unvaccinated COVID-19 admitted patients.  相似文献   

8.

Objective:

To analyze the body fat (BF) content and distribution modifications in coronary artery disease (CAD) patients in response to a 1‐year combined aerobic and resistance exercise training (CET) program.

Design and Methods:

We followed two groups of CAD male patients for 12 months. One group consisted of 17 subjects (57 ± 12 years) who engaged in a CET program (CET group) and the other was a age‐matched control group of 10 subjects (58 ± 11 years). BF content and distribution were measured through dual energy X‐ray absorptiometry (DXA) at baseline and follow‐up.

Results:

We found no differences on body mass and BMI between baseline and end of follow‐up in both groups but, in CET group, we found significant reductions in all analyzed BF depots, including total BF (21.60 ± 6.00 vs. 20.32 ± 5.89 kg, P < 0.01), % total BF (27.8 ± 5.5 vs. 26.4 ± 5.4%, P < 0.05), trunk fat (12.54 ± 3.99 vs. 11.77 ± 4.01 kg, P < 0.05), % trunk fat (31.1 ± 6.9 and 29.2 ± 7.1%, P < 0.05), appendicular fat (8.22 ± 2.08 vs. 7.72 ± 2.037 kg, P < 0.01), % appendicular fat (25.7 ± 4.9 and 24.5 ± 4.9%, P < 0.05), and abdominal fat (2.95 ± 1.06 vs. 2.75 ± 1.10 kg, P < 0.05). Control group showed significant increase in appendicular fat (7.63 ± 1.92 vs. 8.10 ± 2.12 kg, P < 0.05).

Conclusions:

These results confirm the positive effect of CET on body composition of CAD patients, despite no changes in body mass or BMI. In this study, we observed no alterations on BF distribution meaning similar rate of fat loss in all analyzed BF depots. These results also alert for the limitations of BMI for tracking body composition changes.  相似文献   

9.
Intensive selection of broilers for faster growth and better feed efficiency resulted in greater susceptibility to metabolic disorders such as ascites syndrome, which is one of the major causes of mortality and economic loss in broiler industry. Whereas cool temperature is one of the primary triggers for ascites, early feed restriction (FDR) significantly alleviates its incidence and mortality. However, little is known about effects of FDR, cold environmental temperature and their interaction on physiological responses in broiler chickens. For this purpose, 320 one-day-old male broilers were divided into two treatment groups of Ad libitum (Ad) and feed restricted (FR) with eight pen replicates each. Chickens in FR group underwent feed access limitation from days 7 to 14 of age. On day 21 half of the birds (four pens) in each group exposed to the cold temperature (CT) and the other half (four pens) continued at normal temperature (NT). Average daily feed intake, average daily weight gain and feed conversion ratio (FCR) were measured at days 7, 14, 21, 28 and 42. At 39 and 46 days of age two chicks with a BW around the pen average were selected from each pen and slaughtered after collecting blood samples. Then, relative weight of internal organs and right ventricle weight per total ventricle weight (RV : TV) ratio were calculated. Compared with NT group, CT birds had higher daily feed intake and FCR (P<0.05) from day 28 to 42. Cumulative ascites mortality in CT chickens was higher (P<0.001) than NT chicks. Within the CT group, ascites mortality in FR chickens was reduced (P<0.001) to 1.25% compared with 8.75% in Ad chicks. Birds in CT group had significantly (P<0.05) thicker right ventricle and greater relative weight of heart, hematocrit and triiodothyronine concentration. However, none of these parameters were affected by FDR. Under cold stress conditions, FDR reduced activity of alanine aminotransferase and aspartate aminotransferase (P<0.05). Serum triglyceride, cholesterol, high-density lipoprotein and total protein were not influenced by either temperature or feeding regimen. In conclusion, these findings suggest that FDR reduces ascites incidence mainly by allowing better development of internal organs, which helps them to cope with the high metabolic pressure and suffer less damage.  相似文献   

10.
The aim of this study was to evaluate a nasal vaccine using antigens derived from sporozoites of Eimeria tenella incorporated into Iscom to protect broiler chicks. Forty-five one-day-old chickens (Cobb), unvaccinated against coccidiosis, were used in this experiment. The birds were maintained in separated battery cages and divided into three groups: G1 (n = 15), G2 (n = 15), and G3 (n = 15). G1 received 50 μg of sporozoites + Iscom vaccine, G2 received Iscom without antigens, and G3 received only PBS. The treatments were administered by nasal route on days 0, 7, and 21 of the experiment. On the 28th day, all birds were challenged with 105 sporulated oocysts of E. tenella. On the challenge day, three birds from each group were euthanized to evaluate lymphocyte proliferation. Lesion scores were obtained from five birds from each group, 7 days after challenge. The remaining animals were euthanized on the 50th day. The mean lymphocyte proliferation responses were significantly different (P = 0.03); G1 was 2.3-2.6 times more elevated than G2, and G3 (P < 0.001). 83% of the birds from G1 showed an IgY antibody reaction by ELISA at challenge. The means for oocysts shedding were 16,890 ± 20,511, 48,080 ± 50,047, and 65,020 ± 74,461, for G1, G2 and G3 birds, respectively. There was no significant difference (P > 0.17) in oocysts shedding between groups. However, the G1 and G2 chicks demonstrated reduction in percentage of oocyst shedding when compared to control birds (G3) by 74.02% and 26.05%, respectively. The average lesion scores were G1 = 0.4, G2 = 1, and G3 = 2. This study demonstrated that the lowest lesion score and oocyst shedding were observed in the birds from the group that received antigens derived from sporozoite with an Iscom adjuvant (G1). These results suggest that this vaccine can induce protection against avian coccidiosis.  相似文献   

11.
Five Rocky Mountain bighorn sheep (Ovis canadensis canadensis), approximately 5 mo old and without detectable antibody titers to respiratory syncytial virus (RSV), were assigned to two groups to study the effects of RSV challenge inoculation in vaccinated (n = 3) and unvaccinated (n = 2) bighorns. The three lambs vaccinated with a modified live bovine RSV vaccine developed a detectable antibody response to the vaccine. Vaccinated and unvaccinated lambs challenged with an ovine isolate of RSV developed increased levels of neutralizing antibody, but clinical signs of disease were not observed. Neutralizing antibody titers to RSV remained higher (2-4-fold) in vaccinated lambs over time when compared to unvaccinated lambs.  相似文献   

12.

Background

Coccidiosis is a major global veterinary health problem in intensively reared chickens. It is caused by apicomplexan parasites of the genus Eimeria.

Principal Findings

A subunit vaccine composed of purified antigens from the gametocytes of Eimeria maxima was used to stimulate the production and transfer of maternal antibodies between breeding hens and their hatchlings. The vaccine was injected into hens twice before they began laying eggs. Immunization had no adverse affects on egg laying or health of the hens and resulted in high antibody levels throughout the life of the hens. Progeny of immunized hens excreted significantly less oocysts of various species of Eimeria in their faeces than chicks from unvaccinated hens. Furthermore, the offspring of vaccinated hens developed stronger natural immunity to Eimeria, so that they were resistant to challenge infection even at 8 weeks of age, well after all maternal antibodies had left their circulation. Field trials were conducted in South Africa, Brazil and Thailand, involving at least 1 million progeny of vaccinated hens and at least 1 million positive control birds (raised on feed containing anticoccidial drugs or immunized with a live vaccine) in each country. Additionally, trials were carried out in Israel involving 60 million progeny of vaccinated hens and 112 million positive control birds. There were no significant differences in growth rate, feed conversion ratios or mortality in the offspring of vaccinated hens compared with the positive control chickens in any of these countries regardless of different management practices, different breeds of chickens or climate.

Conclusions

These results demonstrate that a vaccine composed of antigens purified from the gametocytes of Eimeria can be used safely and effectively to prevent the deleterious effects of coccidiosis. It is the first subunit vaccine against any protozoan parasite to be successfully applied on a commercial scale.  相似文献   

13.
【目的】本文旨在研究猪脾转移因子(TF)对新城疫(ND)病毒弱毒疫苗La Sota株的免疫增强作用及机理,为兽医临床防控提供理论依据。【方法】以4种不同剂量La Sota疫苗株分别单独、与TF联合免疫SPF鸡,14 d后以ND病毒(NDV)参考强毒F48E9株(104.7 ELD50)进行攻毒,采用蛋白质芯片技术测定鸡外周血IL-6、IL-10、IL-16和IL-21浓度,并以血凝抑制(HI)试验和荧光定量RT-PCR方法分别检测鸡ND HI抗体效价和F48E9株的病毒血症水平。【结果】攻毒保护试验表明,单独免疫105.17、104.17、103.17和102.17 EID50剂量时疫苗攻毒保护率分别为100%、55%、0%和0%,半数保护量(PD50)为12 023 EID50;对应剂量联合免疫时疫苗攻...  相似文献   

14.
1日龄非免疫鸡分别接 马立克氏病病毒(MDV)Ⅰ强毒GA株、Ⅰ型MDV疫苗毒CVI988株和Ⅲ型火鸡疱疹病毒(HVT)疫苗株后第4日起,定期采血并和抗MDV囊膜糖蛋白B(gB)单克隆抗体介导的间接免疫荧光试验检测MDV在外周因液单核细胞(PBMCs)中的感染状况。结果发现,自接种Ⅰ型强毒GA株后第4日至鸡发病死亡前,都能检出GA株引起的病毒血症,并于2周左右达到高峰;自接种CVI988株后第4日至第20日止,能检出病毒血症,并于第8天左右达到高峰;自接种HVT后第4日至第16日止,能检出病毒血症,并于第6天左右达到高峰。与此同时,将GA株病毒血症的IFA检测结果与细胞培养上病毒空班计数试验结果比较,发现IFA试验比空斑计数试验更为敏感。本试验既可用于判断对鸡作MDV疫苗免疫的接种效果,又可用于检测MDV野毒感染状态。  相似文献   

15.
Marek's disease has been controlled by vaccination with avirulent strains of MDV. However, the protection mechanism following vaccination is not fully understood. In this study immune responses of PBMC and splenocytes derived from vaccinated chickens challenged with virulent MDV were examined using real-time PCR and ELISA. Higher levels of IFN-γ induction were observed in chickens vaccinated during the latent phase of infection with virulent MDV than in similarly challenged, unvaccinated chickens. Furthermore, the mean expression of IFNGR2 and IFN regulatory factor-3 mRNAs was significantly higher in vaccinated than in unvaccinated chickens. These results show that IFN-γ could be one of the important factors in prevention of MD by vaccination and is effective during the latent phase of the infection.  相似文献   

16.
The objective of this study was to compare the effects of natural clinoptilolite and modified clinoptilolite on growth performance and antioxidant capacity in broiler chicks. Two hundred forty 1-day-old commercial Arbor Acres broilers were randomly distributed into three treatments, each of which had eight replicates. Each replicate contains 10 chicks. Control (CON) group fed with the basal diets, natural clinoptilolite (NCLI) group fed basal diets with 2 % natural clinoptilolite, and modified clinoptilolite (MCLI) group fed basal diets with 2 % modified clinoptilolite for 42 days. The results showed that the 2 % supplementation of natural clinoptilolite and modified clinoptilolite had no adverse effect on growth performance of broilers at 42 days of age. Relative weights of organs were not influenced by dietary treatments at 21 and 42 days. The activity of total nitric oxide synthase was significantly (P?<?0.05) decreased in MCLI group than CON group at 21 days of age. At 21 and 42 days, the activities of glutathione peroxidase, catalase, total superoxide dismutase, total antioxidant capacity (T-AOC) were significantly (P?<?0.05) increased in NCLI and MCLI groups than the CON group while there was no difference in T-AOC between CON and NCLI groups. The malondialdehyde content was significantly (P?<?0.05) decreased in NCLI and MCLI groups than the CON group. It was concluded that the addition of 2 % natural clinoptilolite and modified clinoptilolite to diet can improve antioxidant capacity in broilers, although their effects on growth performance was negligible.  相似文献   

17.
The aim of this study was to identify the effect of inclusion of defatted black soldier fly larvae (Def-BSFL) meal as a protein source on the performance and blood plasma constituents of broiler chickens. A total of 360-day-old chicks were assigned into four dietary groups, which included four different levels of Def-BSFL meal namely control (0% BSFL), T1(4% BSFL), T2 (8% BSFL) and T3 (12% BSFL) for six weeks experimental feeding period. At the end of the experiment, the blood samples of three birds from each treatment were collected to measure plasma constituents. Birds fed control and T1 diets demonstrated higher feed intake during the finisher stage compared with T2 and T3 diets. The heaviest weight for the 6-week feeding trial was recorded at T1 (1043.8 ± 65.9 g). Birds fed T1 (1.1 ± 0.0) and T3 (0.9 ± 0.1) diets displayed lower feed conversion ratio during the finisher stage than those fed control (1.7 ± 0.1) and T2 (1.8 ± 0.3) diets. Birds fed the control diet demonstrated the highest red blood cell with mean and standard deviation of 7.5 ± 0.34, whereas those fed the T2 diet showed the highest haemoglobin levels with mean and standard deviation of 15.8 ± 0.24. Birds fed T1, T2, and T3 diets exhibited a higher number (P < 0.05) of monocytes than those fed a control diet. There were no differences in white blood cell count across all the groups. In addition, birds fed the T2 diet showed higher (P < 0.05) blood urea nitrogen followed by the T3, control, and T1 diets. As a conclusion, the 4% Def-BSFL in the broiler chicken diet could be used to replace fish meal (FM) and soybean meal (SBM) without compromising bird performance and blood traits.  相似文献   

18.
Preventing congenital infection is important for the control of porcine reproductive and respiratory syndrome (PRRS). Recently, in our laboratory, an inactivated porcine reproductive and respiratory syndrome virus (PRRSV) vaccine has been developed. Promising results in young pigs encouraged us to test the vaccine potency to prevent congenital infection. In the present study, the performance of this experimental inactivated vaccine was investigated in pregnant gilts. An advanced protocol was used to test the PRRSV vaccine efficacy. This protocol is based on recent insights in the pathogenesis of congenital PRRSV infections. Three gilts were vaccinated with an experimental PRRSV 07V63 inactivated vaccine at 27, 55, and 83 days of gestation. Three unvaccinated gilts were included as controls. At 90 days of gestation, all animals were intranasally inoculated with 105 tissue culture infectious dose 50 (TCID50) of PRRSV 07V63. Twenty days postchallenge animals were euthanized and sampled. The vaccinated gilts quickly developed virus neutralizing (VN) antibodies starting from 3 to 7 days postchallenge (1.0 to 5.0 log2). In contrast, the unvaccinated gilts remained negative for VN antibodies after challenge. The vaccinated gilts had shorter viremia than the control gilts. Gross pathology (mummification) was observed in 8% of the fetuses from vaccinated gilts and in 15% of the fetuses from unvaccinated gilts. The number of fetuses with severe microscopic lesions in the fetal implantation sites (a focal detachment of the trophoblast from the uterine epithelium; a focal, multifocal, or full degeneration of the fetal placenta) was lower in the vaccinated (19%) versus unvaccinated (45%) gilts (P < 0.05). The number of PRRS-positive cells in the fetal placentae was higher in unvaccinated versus vaccinated gilts (P < 0.05). In contrast, the number of PRRS-positive cells in the myometrium/endometrium was higher in vaccinated versus unvaccinated gilts (P < 0.05). Fifty-seven percent of the fetuses from the vaccinated gilts and 75% of the fetuses from the unvaccinated gilts were PRRSV-positive. In conclusion, implementation of the novel experimental inactivated PRRSV vaccine primed the VN antibody response and slightly reduced the duration of viremia in gilts. It also reduced the number of virus-positive fetuses and improved the fetal survival, but was not able to fully prevent congenital PRRSV infection. The reduction of fetal infection and pathology is most probably attributable to the vaccine-mediated decrease of PRRSV transfer from the endometrium to the fetal placenta.  相似文献   

19.
The aim of this study was to investigate the effects of chronic ethanol intake and cigarette smoke exposure on rat kidney. The animals were divided into four experimental groups: (1) the control group (C), (2) the ethanol group (E), (3) the cigarette smoke group (CS), and (4) the cigarette smoke plus ethanol group (CS+E). Rats in E, CS and CS+E groups were treated with ethanol and/or cigarette smoke for 6 months. The animals were killed and the kidneys were removed to determine the activity of xanthine oxidase (XO), myeloperoxidase (MPO) and the levels of nitric oxide (NO). Histopathological and immunohistochemical analysis were performed in kidney tissues. The activity of XO/g protein were 2.8 ± 0.3, 5.2 ± 0.3, 3.2 ± 0.1, and 7.4 ± 0.7 U for C, E, CS and CS+E groups, respectively. In groups E, and CS+E, the XO values were significantly higher than in group C (P < 0.05). The increase in XO activity of CS was not significantly different from group C (P > 0.05). There was a significant increase in XO activity of group CS+E as compared to CS and E groups (P < 0.05), and also a significant difference in XO activity between E and CS was observed (P < 0.05). The activity of MPO/g protein were 13.5 ± 0.6, 16.2 ± 1.1, 14.7 ± 1.1, 23.8 ± 0.9 U for C, E, CS, and CS+E groups, respectively. While MPO activity of kidneys from group CS+E were significantly higher as compared to C, CS, and E groups (P < 0.05), there was no significant difference among the groups of C, CS, E (P > 0.05). The levels of NO/g wet tissue were 347.7 ± 8.5, 261.1 ± 4.8, 329.8 ± 5.6, and 254.2 ± 3.8 nmol for C, E, CS, and CS+E groups, respectively. In groups of E and CS+E, the NO values were significantly lower than that of group C animals (P < 0.05). Although we detected lower NO levels in the E and CS+E groups than in CS group (P < 0.05), a significant difference in NO levels between CS+E and E groups was not observed. In the histopathological analysis of the kidney slices, severe degenerations in kidney tissues of group CS, E, CS+E were observed. Generally, the histological changes in kidney of CS+E and E groups were more severe than those observed in CS alone. While we observed a strong immunoreactivity for anti-nitrotyrosine antibody in kidneys of group CS+E, examination of sections from rat kidneys in group E revealed moderate staining. On the other hand, group CS had very little immunostaining. There was no immunostaining in group C.We concluded that chronic ethanol administration and cigarette smoke exposure may cause oxidative and nitrosative stress which lead to rat kidney damage.  相似文献   

20.
Enterotoxaemia vaccine is a polyvalence vaccine from different types of Clostridium perfringens, and C. septicum toxins that prevents various diseases, the most important one being enterotoxaemia in sheep. The aim of the present study was to evaluate the enterotoxaemia vaccine effects in reducing isolates of intestinal clostridia genus specifically C. perfringens. Sheep dung samples were randomly collected from 10 places in Kerman, Iran. The samples were taken from 90 vaccinated Kermani sheep against enterotoxaemia and 50 unvaccinated sheep of same age from flocks with similar management. Following processing and culture of the samples, colonies were identified applying morphological, gram stain and biochemical tests. Using these tests C. perfringens were isolated from 27 out of 50 unvaccinated sheep (54.0%) and from 2 out of 90 vaccinated sheep (2.2%). All of the clostridia isolates were analyzed by multiplex PCR. Genotyping of 2 strains isolated from the vaccinated sheep indicated that these strains were type D, while the strains isolated from the unvaccinated sheep were types A, B, C and D; 14.8% (4 out of 27), 22.2% (6 out of 27), 40.7% (11 out of 27) and 22.2% (6 out of 27), respectively. However, no isolate containing the iota gene (type E) was detected. Vaccination against enterotoxaemia had a significant effect (P < 0.01) on reducing C. perfringens isolates. Occurrence of the disease in the vaccinated and unvaccinated groups was 3.3% and 64.0% (P < 0.01), respectively.  相似文献   

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