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Enhanced antibody response in cattle against Leptospira hardjo by intradermal vaccination
Abstract
A commercial killed Leptospira hardjo vaccine (with adjuvant) and non-adjuvanted preparation of the same vaccine were used in comparison of the effectiveness of the intradermal (i.d.) and subcutaneous (s.c.) routes for these vaccines. The tests were conducted in 50 females aged 6-14 months. After the first vaccination, both types of vaccine elicited a very poor antibody response by both routes of vaccination. However, after booster vaccination, the commercial vaccine (with adjuvant) elicited a remarkable immune response which was twice as high by i.d. compared with s.c. vaccination. No local or general adverse reactions were observed after i.d. vaccination with the adjuvanted commercial vaccine (potassium aluminium sulphate).
... Em uma criação extensiva de bovinos, LITTLE et al. (1992) constataram que a leptospirose em sua forma endêmica era causada pelo sorovar hardjo, e que a utilização da vacinação anual por um período de cinco anos, associada ao tratamento dos animais infectados com dihidroestreptomicina, foi suficiente para controlar e erradicar a doença. Duas bacterinas comerciais monovalentes com o sorovar hardjo foram testadas por SAMINA et al. (1997), sendo uma com e outra sem adjuvante. No estudo, foi utilizada a inoculação por via intradérmica e subcutânea, com duas aplicações com intervalo de sete semanas. ...
... a que atingiu seu pico no 7 o dia pósvacinação e depois persistiam até o 90 o dia, sem apresentar diminuição significativa dos títulos sorológicos. Entretanto,BOLIN et al. (1989a) verificaram em bovinos não infectados, vacinados com dose única de bacterina pentavalente, que os títulos foram iguais ou superiores a 40 após três semanas da inoculação.SAMINA et al. (1997) também obtiveram respostas muito baixas de anticorpos (<80) quando testaram as vias intradérmica e subcutânea para a aplicação de vacinas acrescidas ou não de adjuvante. ...
ABSTRACT
Using the microscopic agglutination test (MAT), the induction of antibodies against Leptospira sp. p was conducted in vaccinated cattle with a commercial polyvalent
vaccine. The homologous serological response was determined by MAT using two vaccinations schemes. The animals used were adult milking cows from six properties in the Northwest Region of the São Paulo State, Brazil. From each herd 20 animals were used, selected after three consecutive tests with 20-day intervals, based on a serological screening with 24 antigens serovars of Leptospira spp. The experimental groups were
constituted by non-reagent animals (groups I, II and III), and reagent animals (groups IV, V and VI). Later the animals were subdivided into control groups (I and IV), groups that received one dosis of vaccine (II and IV) and groups that received one dosis with booster 30 day after the first injection (III and VI). The MAT test was conducted evaluating the animals at the days 0, 15, 30, 45 and 60 from the first injection of the vaccine. The
results have shown no significant titre difference (p>0.05) between vaccinated and non-vaccinated animals. There was no significant difference (p>0.05) in the responses of vaccine titres related to the serological profile of the animals. The vaccination
with booster presented the best response inducing the production of agglutinins only for the hardjo, wolffi, icterohaemorrhagiae and pomona serovars. Additional trials and validation of immunogenic power of the vaccine used in this research is necessary.
Key words: leptospirosis, bovine, vaccination
... Vaccination is the most economic and effective means of preventing leptospirosis. However, since the cross-immunoprotection among antigens from different serogroups and serovars of pathogenic Leptospira species has been reported to be weak [10][11][12], the currently used leptospiral vaccines are usually composed of 3-5 dominant serovars of dead leptospires prevalent in the local regions. And given the limited cross-immunoprotection of the current vaccines, any of the L. interrogans serovars, not included in the vaccine, can still cause fulminant epidemic of leptospirosis [13,14]. ...
... Interestingly, in the immunoprotective test we found that the vaccine composed of three heat-killed L. interrogans serovars Lai, Lin and Autumnalis with lipL32-1 and lipL41-1 genes provided 100% protective rate to the guinea pigs challenged with L. interrogans strain Lai, but presented much lower protective rate (58.3%) in the animals challenged with L. borgpetersenii strain Pishu having lipL32-2 and lipL41-2 genes, which offers partial evidence to explain the absence of cross-immunoprotection of whole-leptospire dead vaccines [10][11][12][13][14]. This trigeminy vaccine did not confer full protection to the animals challenged with the strain Pishu because this particular strain belongs to the species L. borgpetersenii, and the whole-cell vaccine is composed exclusively of L. interrogans serovars. ...
Leptospirosis, caused by different Leptospira species, is one of the most widespread zoonotic infections worldwide. Here we expressed three major leptospiral lipoproteins and examined their immunogenicity. All the pathogenic Leptospira strains tested possess the lipL21, lipL32 and lipL41 genes, but the latter two can be further divided into different gene types (lipL32-1, lipL32-2, lipL41-1, lipL41-2). Microscopic agglutination test revealed that rLipLs antisera had extensive cross-immunoagglutination among the 178 leptospiral strains in which rLipL32-1 contributed the highest agglutination titer. The rLipLs-based ELISAs established in this study demonstrated that in the sera of 385 leptospirosis patients infected with different serovars of Leptospira interrogans, rLipL32-1 had the highest positive rates for IgG and IgM (89.4-98.7%), followed by the IgG/IgM positive rates of rLipL21 (87.0-96.1%) and rLipL32-2 (86.5-96.9%), while the two rLipL41s presented the lowest IgG/IgM positive rates (69.9-83.9%). The immunoprotective levels in guinea pigs of rLipL32-1 (58.3% and 66.7%) were the highest, compared to those of the other rLipLs (25.0-58.3%). Multiple different rLipLs would increase immunoprotective levels (from 58.3% and 66.7% to 83.3% and 91.7%). The data suggest that all the rLipLs are the genus-specific superficial antigens of pathogenic Leptospira species and should be considered in designing universal vaccines against leptospirosis.
... Em uma criação extensiva de bovinos, LITTLE et al. (1992) constataram que a leptospirose em sua forma endêmica era causada pelo sorovar hardjo, e que a utilização da vacinação anual por um período de cinco anos, associada ao tratamento dos animais infectados com dihidroestreptomicina, foi suficiente para controlar e erradicar a doença. Duas bacterinas comerciais monovalentes com o sorovar hardjo foram testadas por SAMINA et al. (1997), sendo uma com e outra sem adjuvante. No estudo, foi utilizada a inoculação por via intradérmica e subcutânea, com duas aplicações com intervalo de sete semanas. ...
... a que atingiu seu pico no 7 o dia pósvacinação e depois persistiam até o 90 o dia, sem apresentar diminuição significativa dos títulos sorológicos. Entretanto,BOLIN et al. (1989a) verificaram em bovinos não infectados, vacinados com dose única de bacterina pentavalente, que os títulos foram iguais ou superiores a 40 após três semanas da inoculação.SAMINA et al. (1997) também obtiveram respostas muito baixas de anticorpos (<80) quando testaram as vias intradérmica e subcutânea para a aplicação de vacinas acrescidas ou não de adjuvante. ...
Mediante a utilização da prova de soroaglutinação microscópica (SAM), foi pesquisada a indução de anticorpos contra leptospira em bovinos vacinados com uma bacterina polivalente comercial. Procurou-se avaliar a resposta sorológica homóloga frente a dois esquemas de vacinação. Os animais utilizados foram fêmeas adultas em produção leiteira oriundas de seis propriedades da região noroeste do Estado de São Paulo. Vinte animais de cada propriedade foram escolhidos após três exames sorológicos com 24 sorovares de leptospiras com intervalo de 20 dias, através de triagem sorológica com 24 antígenos de leptospiras. Os grupos foram constituídos de animais não reagentes (I, II e III) e animais reagentes (IV, V e VI). Posteriormente os animais foram subdivididos em grupos controle (I e IV), os que receberam somente uma dose de vacina (II e V) e que receberam duas uma doses de vacina com e dose de reforço após 30 dias (III e VI). Os animais foram monitorados por meio da SAM nos dias 0, 15, 30, 45 e 60 após a primeira aplicação da vacina. Os resultados obtidos revelaram que não houve diferença significativa (p>0,05) entre os animais vacinados e não vacinados. Não houve diferença significativa (p>0,05) nas respostas de títulos vacinais com relação ao perfil sorológico apresentados pelos animais. A vacinação com reforço apresentou melhor desempenho e a indução produção de aglutininas somente ocorreu contra os sorovares hardjo, wolffi, icterohaemorrhagiae e pomona. Há a necessidade de maiores estudos sobre o poder imunogênico da vacina utilizada no experimento.
... The development a new tools for leptospirosis treatment, especially an effective vaccine, would be considered the best solution against Leptospira. However, previous researches showed the weak cross-immunoprotection of antigens from traditional vaccine to different serogroups and serovars of pathogenic Leptospira species [12]. In addition, both inactivated and attenuated vaccines are associated with potential risks, such as aches and anaphylaxis, and the serovarspecific immunity is only short-term [4]. ...
... Studies revealed that heatkilled inactivated vaccine induces a strong antigen-specific proliferative response by peripheral blood mononuclear cells (PBMC) which was reported in vaccinated cattle after 2 months of the initial booster dose 81 . The whole-cell killed vaccine in the study illustrated that the antibody levels were low [1:05] during first booster dose and the significant increase in the antibody levels were observed in the 2 nd booster dose (1:20) and 3 rd booster dose (1:40) so this confirms an elevated immune response after successive booster doses (Graph 4) 82 . The pathological studies confirmed that the vaccinated mice (Fig 13) showed no significant change when compared to that of control mice (Fig 11) in the internal body organs whereas the combination of virulent serovars injected into the albino mice (Fig 12) showed severe enlargement of the organs such as spleen, liver, pancreas, etc. ...
Leptospirosis is a fatal infectious disease caused by different serovars of Leptospira spirochetes affecting humans and animals. In the present study, the trials of the whole-cell killed formalin treated monovalent vaccine using Leptospira icterohaemorrhagiae and trivalent vaccine using Leptospira icterohaemorrhagiae, Leptospira louisiana, and Leptospira hebdomadis were studied. The serum electrophoresis studies were done after administration of the vaccine into the experimental albino mice along with the booster dose of the vaccinated serum by densitometric readings. Similarly, the pathological observations were made by dissecting the virulent mice, vaccinated mice, and comparing them with the control mice. The MAT titre was also studied after the booster dose administration of the vaccinated serum. The monovalent and trivalent whole-cell killed formalin treated vaccines shows significant raise in the total proteins, albumin, globulin, α 1 globulin, α 2 globulin, β globulin and γ globulins of the serum as well as increase in significant levels in the antibody levels after the administration of the booster dose at an interval of 14 days.
... Partner switching upon phosphorylation and dephosphorylation is the main regulatory mechanism of this protein cluster in response to stresses. This has been studied mostly in B. subtilis (12)(13)(14) and seldom in L. monocytogenes. In unstressed B. subtilis, RsbW sequesters B into an association that prevents it from interacting with RNA polymerase. ...
Listeria monocytogenes is a saprophytic bacterium that thrives in diverse environments, and causes listeriosis by ingesting contaminated food. RsbX,
a putative SigmaB (σB) regulator, is supposed to maintain the ready state in the absence of stress and reset the bacterium to the initial state
in post-stress stage in Bacillus subtilis. We wondered if RsbX is functional in L. monocytogenes under different scenarios of stress conditions. Genetic deletion and complementation of the rsbX gene were combined with survival tests and transcriptional and translation analysis of σB expression in response to stresses. We found that deletion of rsbX increased survival under secondary stress following recovery growth after primary stress or following the stationary phase
culturing. The ΔrsbX mutant had higher expression of σB than its parent strain in recovery stage following primary sodium stress and in stationary phase cultures. Apparently increased
σB expression had contributed to improved survival in the absence of RsbX. There were no significant differences in survival
rates or σB expression in response to primary stresses between the rsbX mutant and its parent strain during the exponential phase. Therefore, we provide clear evidence that RsbX is a negative regulator
of L. monocytogenes σB during the recovery period after the primary stress or in the stationary phase, thus affecting its survival under secondary
stress.
... The antibody response of the vaccines prepared in this study was also assessed in cattle under field condition for a period of 180 days. For, both the vaccines, first vaccination was done at about four month old animals and booster immunization was done four weeks later as suggested by several earlier workers (Bey and Johnson, 1986;Palit et al., 1996;Samina et al., 1997). Vaccination did not cause any adverse reaction in the vaccinated cattle. ...
Two different inactivated vaccines for bovine leptospirosis were prepared with five different Leptospira serovars namely australis, ballum, hardjo, hebdomadis and pomona and adjuvanted with Montanide ISA 206 (Vaccine–I) or adjuvanted with Aluminium hydroxide gel (Vaccine–II) to evaluate the efficacy of the vaccines. The immunogenicity of the vaccines was studied in rabbits under experimental condition and in cattle under field condition for a period of 180 days. Antibody response against five different leptospira serovars ranged from 6.84 log2 to 9.64 log2 (GM-MAT titres) in rabbits at 180 days after vaccination with vaccine I, whereas in vaccine II, the titre value ranged from 5.64 log2 to 7.44 log2. In the case of cattle under field condition, vaccine I showed GM-MAT titres of 6.84 log2 to 7.69 log2 against five different serovars at 150 days following vaccination. Such titres were maintained following vaccination with vaccine II for 120 days only. It is concluded that vaccine I is a better vaccine than vaccine II. However both the vaccines showed high immune response of 5.64 log2 at six months of immunization. Vaccination did not cause any adverse reaction in the vaccinated cattle.
... Faine et al. (1999) relatam que resultados de triagens em bovinos têm diferido desde o completo sucesso, significando que todos os animais vacinados estavam protegidos e os controles não, até a completa falência, com diferença não significativa entre os grupos de controle e experimental. Autores como Bolin et al. (1989), Favero et al. (1997) e Samina et al. (1997) encontraram quase nenhuma resposta sorológica após a vacinação com bacterinas comerciais. Porém, destacam-se os resultados obtidos por Del Fava et al. (2004) quando trabalharam com bovinos da raça Nelore manejados extensivamente. ...
No presente estudo, 100 fêmeas bovinas foram divididas em cinco grupos de 20 animais cada. Os grupos experimentais receberam quatro diferentes vacinas comerciais (B, C, D e E), e um grupo permaneceu como controle. Amostras foram colhidas no dia da aplicação da primeira dose e nos dias 3, 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91, 120, 150 e 180 pós-vacinação (PV). A triagem dos animais foi feita pela análise sorológica com 6 antígenos de leptospiras, escolhendo-se os animais não reagentes. Os títulos de anticorpos foram monitorados pela soroaglutinação microscópica (SAM) com os sorovares Canicola, Grippotyphosa, Hardjo, Icterohaemorrhagiae, Pomona e Wolffi. Todas as vacinas induziram, aos 3 dias PV, títulos de anticorpos aglutinantes para os sorovares Hardjo e Wolffi, que persistiram até o 150º dia PV. Os sorovares Hardjo e Wolffi induziram os maiores títulos de anticorpos aglutinantes. A vacina D, apesar de não possuir o sorovar Wolffi em sua composição foi capaz de induzir anticorpos aglutinantes contra este sorovar. Somente foram detectados anticorpos contra o sorovar Canicola nos animais vacinados com a bacterina D. A vacina que induziu os maiores títulos médios de anticorpos, considerando todos os sorovares testados foi a D.
... Faine et al. (1999) relatam que resultados de triagens em bovinos têm diferido desde o completo sucesso, significando que todos os animais vacinados estavam protegidos e os controles não, até a completa falência, com diferença não significativa entre os grupos de controle e experimental. Autores como Bolin et al. (1989), Favero et al. (1997) e Samina et al. (1997) encontraram quase nenhuma resposta sorológica após a vacinação com bacterinas comerciais. Porém, destacam-se os resultados obtidos por Del Fava et al. (2004) quando trabalharam com bovinos da raça Nelore manejados extensivamente. ...
ABSTRACT
Using the microscopic agglutination test (MAT),
the induction of antibodies against Leptospira sp. p was
conducted in vaccinated cattle with a commercial polyvalent
vaccine. The homologous serological response was determined
by MAT using two vaccinations schemes. The animals used were
adult milking cows from six properties in the Northwest Region
of the São Paulo State, Brazil. From each herd 20 animals
were used, selected after three consecutive tests with 20-day
intervals, based on a serological screening with 24 antigens
serovars of Leptospira spp. The experimental groups were
constituted by non-reagent animals (groups I, II and III), and
reagent animals (groups IV, V and VI). Later the animals were
subdivided into control groups (I and IV), groups that received
one dosis of vaccine (II and IV) and groups that received one
dosis with booster 30 day after the first injection (III and VI).
The MAT test was conducted evaluating the animals at the days
0, 15, 30, 45 and 60 from the first injection of the vaccine. The
results have shown no significant titre difference (p>0.05)
between vaccinated and non-vaccinated animals. There was no
significant difference (p>0.05) in the responses of vaccine titres
related to the serological profile of the animals. The vaccination
with booster presented the best response inducing the production
of agglutinins only for the hardjo, wolffi, icterohaemorrhagiae
and pomona serovars. Additional trials and validation of
immunogenic power of the vaccine used in this research is
necessary.
... Bacterins are widely used for preventing clinical leptospirosis (9,13,14), renal colonization by leptospires (9), agalactia (22), abortions and productive losses in animals. The immunizing activity is increased by the addition of proper adjuvants as aluminum hydroxide (13). ...
Three leptospiral bacterins, produced with different serovars of Serogroup Sejroe, namely the hardjo (bacterin A), wolffi (bacterin B) and guaricura (bacterin C), were evaluated in male hamsters (Mesocricetus auratus) by comparing the agglutinating and neutralizing antibodies titers using microscopic agglutination (MAT) and in vitro growth inhibition (GIT) tests. The immunization schedule was based on two 1.0 mL doses of non-diluted formalininactivated whole culture bacterin given through subcutaneous route with 10-day interval. The challenge was performed ten days after the second vaccine dose, when the animals were inoculated with 0.2 mL of non-inactivated cultures of each serovar through intraperitoneal route. On the 21st post-challenge day (PCD), all animals were bled and their sera were joined in pools (n=8) and tested by MAT and GIT. All vaccinated and control animals presented no clinical signs of leptospirosis after the challenge, but the serovar guaricura was isolated from the kidneys of control animals on the 21st PCD. The MAT results showed cross agglutinins between serovars hardjo and wolffi, and between wolffi and guaricura. The GIT results revealed the presence of cross neutralizing antibodies between serovars wolffi or guaricura against hardjo, wolffi and guaricura. It was found that the tested strain of serovar hardjo did not produce detectable levels of neutralizing antibodies, indicating its poor immunogenicity.
... A commercial inactivated leptospirosis vaccine (with adjuvant) induced a poor antibody production in cattle during preliminary vaccination. However, after booster vaccination, this vaccine caused a remarkable immune response [128]. Hydrostatic pressure-treated leptospires can be used as inactivated vaccine. ...
Leptospirosis is a serious infection disease caused by pathogenic strains of the Leptospira spirochetes, which affects not only humans but also animals. It has long been expected to find an effective vaccine to prevent leptospirosis through immunization of high risk humans or animals. Although some leptospirosis vaccines have been obtained, the vaccination is relatively unsuccessful in clinical application despite decades of research and millions of dollars spent. In this review, the recent advancements of recombinant outer membrane protein (OMP) vaccines, lipopolysaccharide (LPS) vaccines, inactivated vaccines, attenuated vaccines and DNA vaccines against leptospirosis are reviewed. A comparison of these vaccines may lead to development of new potential methods to combat leptospirosis and facilitate the leptospirosis vaccine research. Moreover, a vaccine ontology database was built for the scientists working on the leptospirosis vaccines as a starting tool.
Leptospiral serovars namely australis, ballum, hardjo, hebdomadis and pomona were selected as seed bacteria for the preparation of Leptospira vaccines based on the seroprevalence studies conducted using 3605 bovine serum samples of Tamil Nadu, Andhra Pradesh and Gujarat states. By incorporating the above serovars two different kind of adjuvanted pentavalent vaccines were prepared. Vaccine I was adjuvanted with Montanide ISA 206 and vaccine II was adjuvanted with Aluminium hydroxide gel. The two vaccines were found to be safe and potent, hence considered as better vaccines.
In this study, a total of 120 non purposive serum samples (Cows-68; Bullocks-32; Bulls-20) randomly collected from different breeds of bovine (Cross breed- 41; Indigenous- 61 and Non-descript-18) in six districts (Bargarh-40; Angul-15, Koraput-22, Boudh-14, Nayagarh-11, Jagatsinghpur-18) of Odisha by field veterinary officers during surveys from April to May 2013 were included. These samples were tested at 1:100 dilution in microscopic agglutination test (MAT) using live antigens of 14 reference leptospiral serovars in order to investigate the seroprevalence of bovine leptospirosis. The overall seroprevalence of 42.5% (51/120=CI: 95% 34.0 to 51.4) with 48.5% in cows, 28.1% in bullocks and 45.0% in bulls was observed. The overall analysis of chi-square test revealed that seroprevalance in bovine are associated with age (2 =5.78, p<0.10), whereas not associated with breed type and health status. Among the targeted districts, high prevalence was observed in Nayagarh (81.8%) followed by Bargarh (47.5%), Jagatsinghpur (44.4 %) and
Boudh (42.8%). In general, the prevalence across the sample regions was significant (2 =12.45, p<0.05) indicating the prevalalence was associated with regions. Out of 51 reacted sera, 13 samples showed reactivity with more than one serovars representing 25.5%. The predominant leptospiral antibodies determined against frequency distribution of the serovars were: Australis (50.9%); Hardjo (23.5%); Canicola, Tarassovi and Kaup (7.8%); Pomona, Hurstbridge (5.9%); Bankinang, Javanica, Hebdomadis and Pyrogenes (3.9%); and Icterohaemorrhagiae, Grippotyphosa and Shermani (2.0%). This study supports that bovines may have a role in maintaining Australis serovar apart from being a well known reservoir for Hardjo serovar in Odisha state, India
The possibility to apply a needleless (by jet-injector) rabies vaccine was verified experimentally on target animal species, i.e. cattle and sheep. The results were compared with the data obtained by classic intradermal (i.d.) and intramuscular (i.m.) routes of vaccine administration. The post-vaccination Immoral immunity level was evaluated by RFFIT and ELISA methods. Also the level of post-vaccination cell-mediated immunity by the test of a blastogenic response of blood lymphocytes to specific rabies antigen was determined. The results of experiments suggest the advantage of the intradermal administration of rabies vaccines for target animal species, as it is possible to use only one fifth dose of vaccine to provide sufficient anti-rabies protection. When needleless administration of vaccine in cattle was performed, a higher antibody response in comparison with i.m. vaccine administration was detected, although significantly higher titres were recorded only on day 35 after anti-rabies vaccination. No significant differences between classic i.d. and needleless routes of vaccine administration were recorded. Similar results were observed also in the case of cell-mediated immune response to rabies antigen in cattle. The mean titres of rabies antibodies in sheep on day 35 after anti-rabies vaccination suggest that the optimal route of rabies vaccine administration in this animal species is the W. needle or needleless vaccination on the dorsal pail of the car.
Leptospirosis is an occupational zoonosis caused by pathogenic leptospires. In this study, the presence and prevalence of antibodies specific to Leptospira spp. serovar Hardjo in 142 cattle slaughtered between June and July 2011 was investigated using the enzyme-linked immunosorbent assay (ELISA). Five (3.50%) of the 142 cattle sampled were seropositive for antibodies to Leptospira spp. serovar Hardjo. Despite the fact that there was no significant difference (p>0.05) in seropositivity between sexes and between breeds sampled, there was a significant difference (p<0.05) in sero-positivity between the different age groups examined. Leptospirosis is present in cattle slaughtered in the Zango abattoir; butchers and abattoir workers are exposed to infected animals and are at risk of being infected by Leptospira spp. serovar Hardjo.
Intradermal (ID) inoculation has been investigated as a means of vaccinating laboratory animals, domestic farm animals, and humans. Various forms of viral, bacterial, parasitic, and fungal antigens have been administered ID, with varying results. This review emphasizes results from studies reporting clinically relevant outcomes such as clinical protection and body weight change following experimental challenge. Antibody titers, cytokines, cellular responses are included as supportive data. Based on the reports reviewed, ID vaccination is a promising alternative to more traditional routes of vaccination. ID vaccination has particular appeal to the beef cattle industry based on recently emphasized quality assurance issues. It is evident that the ultimate test of vaccine efficacy is the ability to protect against clinical disease under natural challenge conditions. We propose that the immune response of ID vaccinated cattle, using clinically relevant outcomes such as morbidity, mortality, average daily gain and feed efficiency, needs to be further investigated to define the value of this potentially effective and practical means of antigen delivery, particularly for domesticated farm animals.
Ultrasound irradiation and hyperosmotic treatments were compared as facilitators of antigen (BSA) penetration through the skin by bath vaccination and as enhancers of the antibody response in goldfish. The kinetics of BSA penetration and accumulation into the skin, and via it to the blood, and the consequent specific stimulation of the humoral immune response, were studied. The main findings are: (1). ultrasonic treatment is more effective than hyperosmotic treatment in enhancing both antigen transport through the skin and antibody production; (2). the requirements for high antigen concentrations, which are needed for simple bath immersion, could be reduced five times in presonicated fish; and (3). anesthesia, which significantly reduced gill uptake following hyperosmotic treatment, had no effect on skin uptake. The importance of these finding for mass vaccination of adult fish and larvae is discussed.
Effectiveness of 2 pentavalent leptospiral vaccines containing Leptospira interrogans serovar hardjo was evaluated for protection of steers from infection with serovar hardjo type hardjo-bovis. The hardjo component of 1 vaccine was prepared from serovar hardjo type hardjoprajitno. The hardjo component of the other vaccine was prepared from serovar hardjo type hardjo-bovis. Two steers were vaccinated once and 4 steers were vaccinated twice with the pentavalent vaccine containing type hardjoprajitno. Four steers were vaccinated once and 4 steers were vaccinated twice with the pentavalent vaccine containing type hardjo-bovis. Four steers were maintained as non-vaccinated controls. Steers given vaccine containing type hardjo-bovis developed higher mean serum microscopic agglutination titers against serovar hardjo than steers given vaccine containing hardjoprajitno. Six months after the first vaccination, all steers were challenge-exposed on 3 occasions by conjunctival instillation of 10(7) serovar hardjo type hardjo-bovis organisms, and on 1 occasion by conjunctival instillation of urine from a steer shedding hardjo-bovis. All control and all vaccinated steers became infected and shed serovar hardjo type hardjo-bovis in the urine. Lesions were detected in kidneys of 3 of 4 nonvaccinated control steers, 5 of 6 steers given hardjoprajitno vaccine, and 6 of 8 steers given hardjo-bovis vaccine. Leptospires were detected in kidneys of 4 of 4 control steers and 13 of 14 vaccinated steers.
A comparison was made of the efficiency of intradermal and subcutaneous routes of vaccination in immunizing cattle with a killed vaccine of Escherichia coli K99+. In this study 135 heifers aged 8-18 months were included. The effect of the number of intradermal injection sites was examined, as well as the optimal time interval between the initial and booster intradermal vaccination. The intradermal route was found to be significantly superior to the subcutaneous route. The optimal time for intradermal booster was approximately 2 weeks. Increasing the number of intradermal injection sites up to 50 (using the same amount of antigen) did not result in an enhancement of the antibody level.
The long term efficacy of a commercially prepared bivalent vaccine against Leptospira interrogans serovar hardjo and L. interrogans serovar pomona was evaluated in a group of 82 dairy heifers exposed to natural challenge with L. interrogans serovar hardjo for up to 55 weeks after calfhood vaccination. Nineteen heifers were vaccinated twice with a one-month interval, at calfhood (9 to 10 months). A further 18 heifers received a similar calfhood vaccination regimen plus a third injection at adulthood (22 to 23 months), while 19 heifers were vaccinated twice at adulthood only and finally 22 heifers were used as unvaccinated controls.
At 55 weeks after calfhood vaccination and prior to adulthood vaccination, only 2.7% of the vaccinated heifers were found to have leptospiruria compared with 58.5% of the unvaccinated heifers (p<0.0001). Microscopic agglutination (MA) titres at the same time in the unvaccinated heifers ranged from 32 to 4096 while those vaccinated at calfhood ranged from 32 to 64.
Adult vaccination of infected animals did not significantly reduce leptospiruria. Prior to adulthood vaccination, 9 of 19 heifers had leptospiruria, in comparison to 4 of 15 after adulthood vaccination. At the same sampling periods 15 of 22 controls had leptospiruria in comparison to 4 of 9 subsequently tested.
The efficacy of the hardjo component of a hardjo-pomona vaccine was evaluated in yearling heifers under conditions of natural challenge in a commercial dairy herd when endemic hardjo infection was present. Eight heifers received 2 doses of vaccine 4 weeks apart and were run with 10 unvaccinated heifers for a period of 56 weeks. Results from the culture of urine samples showed that the vaccine either prevented leptospiruria to a significant degree (Phardjo infection in the herd.
Following a sudden drop in milk yield in a large dairy herd, leptospiral mastitis due to serotype hardjo was diagnosed serologically and by isolation of the organism from the milk and urine of affected cows. Two milkers subsequently became ill and developed titres to the Hebdomadis serogroup. During the same period the neighbouring herd experienced poor milking performance and a series of abortions and serological evidence suggested recent hardjo infection. The common source of infection appeared to be infected down calving heifers.
A total of 2994 sera, from approximately equal numbers of aborting and normal calving cows, were examined for leptospiral antibodies using a complement fixation test. An analysis of the results indicated that approximately 10% of abortions were associated with leptospiral antibodies.
Some examples of the use of epidemiological techniques in the study of leptospirosis
- Pritchard
Epidemiological study of Leptospira interrogans serovar hardjo from a viable premature calf
- Hatway
Analysis of risk factors for infection of cattle with Leptospira interrogans serovar hardjo
- D G Pritchard
- T N Allsup
- T W Pennycott
- N M A Palmer
- J C Wooley
- M S Richards
Intradermal vaccination of sheep with an inactivated rabies vaccine
- Samina