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Alternative approach to mastitis management – How to prevent and control mastitis without antibiotics?
2018
Sofie Piepers | Sarne de Vliegher
Mastitis affects a high proportion of dairy cows throughout the world and is one of the greater problems faced by the dairy industry today. The disease is still a major cause of economic loss on a dairy farm. Mastitis poses not only negative consequences for the dairy farmer but also for the dairy industry as a number of issues threaten the reputation of milk as a healthy product from healthy animals. The use of antimicrobials is one of those concerns and threats. Antimicrobial usage on dairy farms is most often related to udder health as most medicines are used in prevention and control of mastitis. Antimicrobials remain vital for treatment of bacterial infections in dairy cattle, but in light of the upcoming debate instigated by the potential link between the use of antimicrobial products in animal husbandry and the development of antimicrobial resistance in both animal and human pathogens, there is an urgent need for innovation and alternatives to antibiotic therapy for mastitis treatment and control. Alternative approaches include vaccination, probiotics or beneficial microorganisms and inhibitory substances, immunomodulation, bacteriophages, homeopathy, and plant-derived inhibitory substances, yet only when scientifically-proven evidence is available indicating these alternatives are effective.
Show more [+] Less [-]Early cytokine response after vaccination with Coxiella burnetii phase I in an infected herd of dairy cattle
2018
Małaczewska, Joanna | Kaczorek-Łukowska, Edyta | Szymańska-Czerwińska, Monika | Rękawek, Wojciech | Wójcik, Roman | Niemczuk, Krzysztof | Siwicki, Andrzej Krzysztof
Introduction: Coxiella (C.) burnetii, the aetiological agent of Q fever, is able to modulate the macrophage/T-lymphocyte axis in an infected organism and impair synthesis of monokines and lymphokines. Material and Methods: The purpose of this research was to determine the levels of the cytokines that play a key role in the response to C. burnetii antigens (IL-1β, IL-2, IL-6, IL-10, IFN-γ and TNF-α) in the serum of animals originating from an infected herd prior to vaccination (day 0) and at 1, 7, and 21 days afterwards. Results: The vaccination of animals did not affect the production of IL-6, IL-1β, or IL-2. The serum levels of these cytokines were too low to measure in most of the samples. The initial levels of TNFα, IFNγ, and IL-10 were higher in seropositive than in seronegative animals, although significant differences between seropositive shedders and seropositive nonshedders appeared only in the levels of IFNγ and IL-10. Additionally, the course of the post-vaccination response concerning these two cytokines was different among seronegative nonshedders, seropositive nonshedders, and seropositive shedders. Conclusion: It seems that analysis of the IFNγ and IL-10 concentrations in animal blood serum may have some practical value in an assessment of the health status of seropositive animals and post-vaccination response.
Show more [+] Less [-]Saponin-based Mycoplasma bovis vaccine containing lysozyme dimer adjuvant stimulates acute phase response in calves
2018
Dudek, Katarzyna | Bednarek, Dariusz
Mycoplasma bovis is known as a causative agent of many disorders in cattle. In Europe, there is still a lack of commercial vaccines against M. bovis infection. Acute phase response (APR) is a non-specific host reaction to infection, most seen in changes in production of acute phase proteins. The aim of this study was to analyse APR in calves administered with an experimental M. bovis vaccine. Twelve healthy female calves were divided into two equal groups: experimental and control. The experimental vaccine containing the field M. bovis strain and two adjuvants such as saponin and lysozyme dimer was subcutaneously administered to the experimental group. Phosphate buffered saline was taken as the placebo and given to the control group by the same route as the vaccine. Blood samples were collected prior to the study (day 0), then daily up to day 7, and then each seven days until day 84 post vaccination. The concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-γ (IFN-γ), and inteleukin-4 (IL-4) were determined using commercial ELISA kits. Following the vaccination, a significant increase in SAA, Hp, and IFN-γ concentrations was observed when compared to the unvaccinated calves, whereas the IL-4 concentration was not detectable. The experimental saponin-based M. bovis vaccine containing lysozyme dimer adjuvant visibly stimulated the APR in the calves, and some specific cytokines (Th1-dependent) directly involved in this response.
Show more [+] Less [-]Avian reticuloendotheliosis in chickens – an update on disease occurrence and clinical course
2018
Woźniakowski, Grzegorz | Frant, Maciej | Mamczur, Andrzej
Avian reticuloendotheliosis (RE) represents an important immunosuppressive disease of poultry. The occurrence of RE in both chickens and turkeys has an immunosuppressive effect and may lead to vaccination failures. Avian reticuloendotheliosis virus (REV) is widely distributed in different kinds of birds, causing subclinical infections. Another important issue adhering to this disease is contamination of vaccines against fowl pox (FP) and Marek’s disease (MD) with REV. The capability of REV to integrate into the genome of other larger DNA viruses complicates its diagnosis and prevention. There are no efficient vaccines against RE nor treatment, which also complicates how to limit its impact on poultry farming. This paper reviews the current state of knowledge of this important immunosuppressive agent of poultry emphasising the importance of this problem in terms of diagnosis of RE.
Show more [+] Less [-]Inactivated H5 antigens of H5N8 protect chickens from lethal infections by the highly pathogenic H5N8 and H5N6 avian influenza viruses
2018
Jin, Myongha | Jang, Yunyueng | Seo, Taehyun | Seo, Sang Heui
Introduction: Highly pathogenic Asian H5-subtype avian influenza viruses have been found in poultry and wild birds worldwide since they were first detected in southern China in 1996. Extensive control efforts have not eradicated them. Vaccination prevents such viruses infecting poultry and reduces the number lost to compulsory slaughter. The study showed the efficacy of inactivated H5 vaccine from the H5N8 virus against highly pathogenic H5N8 and H5N6 avian influenza viruses in chickens. Material and Methods: Reverse genetics constructed an H5 vaccine virus using the HA gene of the 2014 H5N8 avian influenza virus and the rest of the genes from A/PR/8/34 (H1N1). The vaccine viruses were grown in fertilised eggs, partially purified through a sucrose gradient, and inactivated with formalin. Chickens were immunised i.m. with 1 µg of oil-adjuvanted inactivated H5 antigens. Results: Single dose H5 vaccine recipients were completely protected from lethal infections by homologous H5N8 avian influenza virus and shed no virus from the respiratory or intestinal tracts but were not protected from lethal infections by heterologous H5N6. When chickens were immunised with two doses and challenged with homologous H5N8 or heterologous H5N6, all survived and shed no virus. Conclusion: Our results indicate that two-dose immunisations of chickens with H5 antigens with oil adjuvant are needed to provide broad protection against different highly pathogenic H5 avian influenza viruses.
Show more [+] Less [-]Determination of lowest immune protective titer against Salmonella gallinarum and Salmonella pullorum in chicken vaccinated with BAU-Salmonella bivalent vaccine
2018
Eusha Islam | Rajib Saha | Md. Golzar Hossain | Shah Md. Abdur Rauf | Md. Mansurul Amin | Sukumar Saha
Objective: The research work was conducted to determine the duration of protective efficacy and lowest immune protective titer of Salmonella bivalent vaccine containing Salmonella gallinarum and Salmonella pullorum prepared at the Livestock and Poultry Vaccine Research and Production Centre (LPVRPC) of Bangladesh Agricultural University (BAU), Mymensingh, Bangladesh.Materials and methods: The experimental chickens were subdivided into four main groups (A, B, C and D). Group A and B were vaccinated with BAU-Salmonella bivalent vaccine with dosed 0.5 mL intramuscularly at the age of seven weeks followed by a booster vaccination at 12 weeks of age while group C and D served as unvaccinated control. The sera samples were obtained at 7, 12, 15, 18, 23, 27, 30, 32, 34, 36 and 41 weeks of age of birds. Results: Significantly elevated level of immune response in terms of antibody production resulted from booster vaccination. Vaccinated chicken showed protective resistance following virulent challenge with isolates of S. gallinarum and S. pullorum (**P [J Adv Vet Anim Res 2018; 5(3.000): 282-289]
Show more [+] Less [-]Evaluation of the efficacy of an attenuated live vaccine based on virulent porcine reproductive and respiratory syndrome virus 2 in young pigs
2018
Lee, S.C., Choong Ang Vaccine Laboratories Co., Ltd., Daejeon, Republic of Korea | Noh, Y.H., Choong Ang Vaccine Laboratories Co., Ltd., Daejeon, Republic of Korea | Lee, S., Kyungpook National University, Daegu, Republic of Korea | Choi, H.W., Choong Ang Vaccine Laboratories Co., Ltd., Daejeon, Republic of Korea | Yoon, I.J., Choong Ang Vaccine Laboratories Co., Ltd., Daejeon, Republic of Korea | Kang, S.Y., Chungbuk National University, Cheongju, Republic of Korea | Lee, C., Kyungpook National University, Daegu, Republic of Korea
The efficacy of the CA-2-MP120 vaccine, a cell culture-attenuated strain of virulent porcine reproductive and respiratory syndrome virus (PRRSV), was assessed in pigs. Despite the persistence of viremia in all vaccinated animals during the immunization period, the virus was not detected in vaccinated pigs following challenge. Furthermore, no pigs in the vaccinated group shed PRRSV nasally, orally or rectally throughout the experiment. Moreover, histopathological lung and lymph node lesions in the immunized group were much milder than those in the unimmunized and challenged group. These results indicated that CA-2-MP120 can provide effective protection against virulent wildtype PRRSV-2.
Show more [+] Less [-]Comparison of 3 vaccination strategies against porcine reproductive and respiratory syndrome virus, Mycoplasma hyopneumoniae, and porcine circovirus type 2 on a 3 pathogen challenge model
2018
Jeong, J. | Kang, I. | Kim, S. | Park, K. H. | Park, C. | Chae, C.
The objective of this study was to compare clinical, microbiologic, immunologic, and pathologic parameters in pigs each concurrently administered porcine reproductive and respiratory syndrome virus (PRRSV), Mycoplasma hyopneumoniae, and porcine circovirus type 2 (PCV2) vaccine from 1 of 2 commercial sources at 21 days of age and challenged with field strains of each of the 3 pathogens. Pigs were challenged with PRRSV and M. hyopneumoniae at 42 days of age (-14 days post-challenge, dpc) followed by a challenge with PCV2 at 56 days of age (0 dpc). Significant differences were observed between vaccinated challenged and unvaccinated challenged groups in clinical (average daily gain and clinical signs), microbiologic (viremia and nasal shedding), immunologic (antibodies and interferon-γ secreting cells), and pathologic (lesions) outcomes. Significant differences were observed among the 3 vaccinated challenged groups in microbiologic (nasal shedding of M. hyopneumoniae and viremia of PCV2) and immunologic (M. hyopneumoniae- and PCV2-specific interferon-γ secreting cells) outcomes. The vaccination regimen for PRRSV vaccine, M. hyopneumoniae vaccine, and PCV2 vaccine is efficacious for controlling triple challenge with PRRSV, M. hyopneumoniae, and PCV2 from weaning to finishing period.
Show more [+] Less [-]Roles of the crp and sipB genes of Salmonella enterica serovar Typhimurium in protective efficacy and immune responses to vaccination in mice
2018
Chen, S. | Liao, C. | Zhang, C. | Cheng, X.
Salmonella enterica serovar Typhimurium has a wide host range and is capable of causing infections ranging from severe gastroenteritis to systemic infection in humans. To determine if attenuated S. Typhimurium strains can serve as safe and effective oral vaccines to prevent typhoid fever, the biologic characteristics of crp and sipB deletion mutants were evaluated. Previous studies had found that the crp and sipB genes are related to Salmonella pathogenicity. In this study, cytotoxicity, protective efficacy, and immune responses of the host were analyzed. Our previous data had shown a significance decrease in virulence for the crp and sipB mutants compared with a wild-type strain. The current study confirmed this finding in HeLa cells and showed that the crp mutant was significantly less cytotoxic (P < 0.05) than the sipB mutant. Mice vaccinated with the crp mutant showed significantly better protection after challenge with the wild-type strain (P < 0.05) and significantly greater responses in serum IgG (P < 0.01) and secretory IgA (P < 0.05) compared with the mice vaccinated with the sipB mutant (P < 0.05). Our results indicate that the crp mutant has the potential to be a vaccine candidate and is safe in mice.
Show more [+] Less [-]Age and sex comparison in determining baseline blood and coagulation profiles in semi-extensive rusa deer (Rusa timorensis)
2018
Abdullah, R. | Chai, I. I. | Hamzah, H. | F. , Jesse F. A. | Ho, H. W. | Hassim, H. A. | Azlan C. A. | Wahid, H.
The objective of the study was to establish the baseline values for blood and coagulation parameters in normal and healthy rusa deer (Rusa timorensis) of different ages and sexes. The samplepopulation consists of 40 rusa deer, divided into four groups of (i) juvenile males (ii) juvenile females (iii) adult males and (iv) adult females. The findings showed significant (p<0.05) higher values in erythrocyte count, calcium concentration and prothrombin time in the adult males compared to adult female rusa deer. On the other hand, the total protein concentration was significantly higher in adult females than adult male deer. No significant differences in blood or coagulation parameters were observed between sexes in the juvenile deer. Between age group, the adult deer had significantly higher mean cell volume, plasma protein and globulin concentration than juvenile rusa deer. Thus, it is necessary to take into account the age and sex of the rusa deer when using blood reference values for the diagnosis of diseases or health assessment.
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