خيارات البحث
النتائج 11 - 20 من 156
Inhibition of lacteal leukocyte phagocytosis by colostrum, nonlactating secretion, and mastitic milk.
1986
Targowski S.P. | Niemialtowski M.
Mortality in swine herds endemically infected with Haemophilus pleuropneumoniae: effect of immunization with cross-reacting lipopolysaccharide core antigens of Escherichia coli.
1986
Fenwick B.W. | Osburn B.I. | Cullor J.S. | Henry S.C. | Olander H.I.
Demonstration of vaccine-induced immunity to anaplasmosis without induction of persistent postvaccinal complement-fixing and agglutinating antibodies in yearling steers.
1985
Corrier D.E. | Johnson J.S. | Wagner G.C.
Influence of Combined Yeast-derived Zinc, Selenium and Chromium on Performance, Carcass Traits, Immune Response and Histomorphological Changes in Broiler Chickens
2020
Basant Mohsen Sobhi | Esam Yousef Ismael | Ebtihal Elleithy | Mabrouk Elsabagh | Khaled Nasr El-din Fahmy
This study was carried out to assess the effects of dietary supplementation of yeast-based Zn, Se, and Cr on growth performance, carcass characteristics, immune response, and histomorphological changes in broiler chickens. A total of 1092 one-day-old unsexed broilers of Ross 308 strain were randomly allocated into two equal treatment groups (6 equal replicates/ group). Birds were fed the dietary treatments from day 1 to day 35 of age. The first group was fed a basal diet without yeast-based Zn, Se and Cr supplementation (control). The second group was fed a basal diet supplemented with 1.5 mg, 0.15 mg and 2 µg / kg diet of Zn, Se, and Cr, respectively. The yeast-based Zn, Se and Cr increased (P<0.05) the growth rate, carcass traits and improved feed conversion ratio compared to control. The antibody titer against avian influenza and the relative weight of bursa, thymus and spleen were increased (P < 0.05) in broilers supplemented with yeast-based Zn, Se, and Cr compared with the control. The intestinal villi height and crypt depth and bursa diameters were increased in broilers fed the yeast-based Zn, Se and Cr supplemented diet. In addition, there was an increase in the lymphocytic infiltration in the bursa and a decrease in germinal centers in the submucosal lymph nodules of the ileum of birds supplemented with yeast-based Zn, Se and Cr compared to the control. In conclusion, dietary supplementation of yeast-based Se, Cr, and Zn in combination could improve growth performance, carcass traits, immune responses and histo-morphological parameters in broiler chickens.
اظهر المزيد [+] اقل [-]Studies on infectious bursal disease maternal immunity decay curve in native and Lohmann chicken breeds
2018
M. F. El-Kady | A. M. Dahshan | H. M. Madbouly
This study was done to evaluate and study the decaying curve of IBD MDAbs of the native chicken breeds including (Fayoumi, Dandrawi, Senawi and Baladi) were taken in consideration as compared with (Lohmann white) layer type breed. The results showed that the decline of maternal immunity of IBDV in Lohmann is the faster followed by Senawi, Baladi, Fayoumi and Dandrawi and the 1 day IBD ELISA titers were shown to be nearly equal in Senawi (5449 ± 371) and Lohmann (4536±437) and titer of Baladi chicks was close to the for mentioned two breeds (5327±371), the Dandrawi (4649±331) and Fayoumi (4596±857) are lower but close to each other. The standard deviation (SD) values recorded in Fayoumi breed showed great variation in the recorded titers, while of the other 4 groups seamed to be homogenous. Comparing the 22 day decline manner in titer it was clear that the loss in titer in Fayoumi (3494) and Lohmann (3413) was nearly equal and followed by Dandrawi (3093) and Baladi (2972) those showing lower titers. The recorded unprotected titer ≤ 400 was detected at 43 days in Lohmann, Baladi and Senawi, 37 days in Dandrawi and 31 in Fayoumi. Percentage of decline from its original values showed that Fayoumi last (75.95%) at 22 days followed by (66.53%) in Dandrawi followed by (62.78%) Lohmann,(55.79) Baladi and (55.19) Senawi. Different breeds showed different slope values that indicate differences in the decay of maternal antibodies. The predication of antibody titer for each breed as the slope in decline curve in Lohmann chicks showed highest values followed by Dandrawi chicks while the Fayoumi and Baladi were as the same values and on the other hand the Senawi showed the lowest value.
اظهر المزيد [+] اقل [-]Molecular characteristics of fowl adenovirus strains detected in broiler chickens on diets without immunostimulant supplements
2024
Niczyporuk Jowita Samanta | Kozdruń Wojciech | Tomczyk Grzegorz | Piekarska Karolina | Barabasz Marcin | Michalski Marcin
Outbreaks of fowl adenovirus (FAdV) infection in chicken flocks in Poland threaten birds’ health and lives and are rising in frequency. The risk of these infections in immunocompromised poultry flocks with developed clinical symptoms was analysed through virus detection in broiler chicks and correlation of cases with the birds’ immune strength.
اظهر المزيد [+] اقل [-]Evaluation of a canine transmissible venereal tumour cell line with tumour immunity capacity but without tumorigenic property
2019
Zayas, Yareellys Ramos | Molina, Moisés Armides Franco | Guerra, Reyes Tamez | Padilla, Cristina Rodríguez
Introduction: Canine transmissible venereal tumour (CTVT) is a sexually transmitted tumour affecting dogs worldwide, imposing a financial burden on dog owners. A stable culture cell line in continuous passages for >18 months has only been achieved once. The present study investigated a stable CTVT cell line isolated from a bitch and its potential as a vaccine. Material and Methods: A biopsy from a 2-year-old mongrel bitch with CTVT was obtained for histopathological confirmation and isolation of tumour cells. The isolated cells were cultured to passage 55 and characterised by flow cytometry, with karyotyping by GTG-banding and by PCR detection of myc S-2 and LINE AS1. The isolated CTVT cell line was also used as a preventive vaccine in a canine model. Results: Histopathological analysis of the isolated tumour cells revealed typical CTVT characteristics. Constant proliferation and stable morphological characteristics were observed during culture. Phenotypic analysis determined the expression of HLA-DR⁺, CD5.1⁺, CD14⁺, CD45⁺, CD83⁺, CD163⁺, and Ly-6G-Ly-6C⁺. GTG-banding revealed a mean of 57 chromosomes in the karyotype with several complex chromosomal rearrangements. LINE-c-myc insertion in the isolated CTVT cell line at 550 bp was not detected. However, a 340-bp band was amplified. Isolated CTVT cell line inoculation at a concentration of 1×10⁸ did not induce tumour growth in bitches, nor did a challenge with primary CTVT cells. Conclusion: The present study successfully identified and isolated a stable CTVT cell line that may be useful in CTVT prevention.
اظهر المزيد [+] اقل [-]Changes in blood lymphocyte subpopulations and expression of MHC-II molecules in wild mares before and after parturition
2017
Krakowski, Leszek | Bartoszek, Przemysław | Krakowska, Izabela | Stachurska, Anna | Piech, Tomasz | Brodzki, Piotr | Wrona, Zygmunt
Introduction: Pregnancy is a physiological state in which the immune system undergoes certain changes. On the one hand, by depleting cell defence mechanisms, it favours development and maintenance of the pregnancy. At the same time cells of the immune system ensure resistance to many risk factors, including infectious agents.Material and Methods: The study was carried out on 24 Polish Konik breed mares which were divided into two equal groups. The first group (group I) included mares living in the reserve. The second group (group II) comprised mares maintained under conventional conditions in the stables. The blood samples were collected for the first time in the perinatal period, i.e. 2 weeks before parturition (trial 0), then within the first 24 h after delivery, and then on 7ᵗʰ and 21ˢᵗ day after foaling. Flow cytometric analysis of lymphocyte expressing TCD4+, TCD8+, CD2+, and MHC class II antigens was performed.Results: Before the delivery, in group I there was a significantly higher CD4:CD8 ratio compared to group II (P ≤0.05). Similarly, significantly increased CD4:CD8 ratio in group I was noted within 24 h after parturition (P ≤0.001) and it was also observed on 7ᵗʰ day (P ≤0.03) and 21ˢᵗ day after foaling (P ≤0.02). In the first 24 h after parturition, a significant decline of lymphocytes CD8+ (P ≤0.02) was noted. No significant differences in terms of lymphocytes CD2+ and CD3+ were observed. Expression of MHC-II molecules before and after the parturition was higher in group I compared to group II; however, the difference between the groups was not significant.Conclusion: The results obtained indicate that mares living in the reserve display higher activity of cell defence mechanisms.
اظهر المزيد [+] اقل [-]Selected aspects related to epidemiology, pathogenesis, immunity, and control of African swine fever
2016
Woźniakowski, Grzegorz | Frączyk, Magdalena | Niemczuk, Krzysztof | Pejsak, Zygmunt
African swine fever (ASF) is currently one of the most severe viral infections of domestic pigs, wild boars, and other hosts belonging to Suidae family. ASF is also considered as the most complex and devastating infectious and haemorrhagic disease of swine due to its severe socio-economic impact and transboundary character. ASF it is a notifiable disease and due to the lack of specific treatment and vaccine, the disease can be only limited by the administrative measures comprising wild boar hunting and stamping out of affected pigs. ASF occurred for the first time in Kenya in 1921 while in Europe (Portugal) the virus was detected at the end of the 1950s. In spite of successful eradication of this threat in a number of affected regions, the virus remains endemic in both feral and domestic pigs in Africa and Sardinia. The ‘new era’ of ASF started in 2007 after its re-introduction to Georgia. Following its intensive expansion, the virus spread to other Caucasian countries, including the territory of the Russian Federation. In 2014 the virus reached Ukraine, Belarus, and, consequently, European Union countries: Lithuania, Latvia, Estonia, and Poland. The occurrence of ASF in wild boars and pigs had a severe impact on both epidemiology and economy because of the national and international transport and trade consequences. Up to date, starting from the February 2014, eighty ASF cases in wild boar and three outbreaks in domestic pigs have been diagnosed. Taking into account the diverse rate of spread in Poland, this review aims to present and discuss the current state of knowledge on ASF including its epidemiology, pathology, transmission, and perspectives of control.
اظهر المزيد [+] اقل [-]Oxidative stress and antioxidant defence markers in muscle tissue of rainbow trout (Oncorhynchus mykiss) after vaccination against Yersinia ruckeri
2016
Introduction: The goal of this study was to assess the influence of vaccination against enteric redmouth disease on oxidative stress biomarkers and antioxidant defence in the muscle tissue of rainbow trout (Oncorhynchus mykiss Walbaum) vaccinated against Yersinia ruckeri in the first and second month after immunisation. Material and Methods: Healthy fish were vaccinated orally with inactivated whole cells of a virulent strain of Y. ruckeri. One and two months after immunisation the muscle samples were collected. Results: No significant difference was noted in lipid peroxidation level in either the first or second month after vaccination, while aldehydic and ketonic derivatives of oxidatively modified proteins (OMB) in the vaccinated group were significantly lower in the second month compared to those in the first month after vaccination (P < 0.05). The content of ketonic derivatives of OMB in muscles in the first month after immunisation was higher compared to untreated control. All these culminated in a depletion of glutathione peroxidase (GPx) activity and low level of total antioxidant capacity (TAC). Conclusion: Correlations between catalase activity and lipid peroxidation and TAC confirmed the pivotal role of catalase in antioxidant defence during immunisation. From a broader perspective, it is suggested that immunisation of fish with Yersinia vaccine is associated with induced free radical formation and oxidative stress. Free radicals would therefore be at least partially responsible for the induction of both humoral and cellular elements of the immunity and increased protective immunity against Y. ruckeri infection.
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