Made available in DSpace on 2015-04-09T12:28:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-05-21Bitstream added on 2015-04-09T12:47:39Z : No. of bitstreams: 1 000814747.pdf: 821876 bytes, checksum: d4d584e2c4157af6634d7bbf44844fa4 (MD5) / O tifo aviário é uma doença sistêmica causada por Salmonella enterica subesp. enterica sorovar Gallinarum biovar Gallinarum (SG). Esta bactéria é altamente patogênica para aves em qualquer idade, causando mortalidade inclusive em aves adultas. No entanto, a progressão dos sinais clínicos em galinhas pode diferir entre as diferentes variedades de aves. Aves de variedade branca são consideradas mais resistentes e dificilmente se observa mortalidade. Aves de variedade vermelha são suscetíveis e desenvolvem quadros clínicos mais severos com altas taxas de mortalidade. O objetivo do presente estudo foi avaliar o desenvolvimento da doença e infiltrado de linfócitos T γδ durante a infecção por SG em diferentes variedades de aves. Neste trabalho, utilizaram-se 50 aves comerciais para postura de variedade branca e 60 aves comerciais para postura de variedade vermelha que foram distribuídas em quatro grupos: grupo A (controle de aves brancas), grupo B (aves brancas infectadas), grupo C (controle de aves vermelhas) e grupo D (aves vermelhas infectadas). As aves dos grupos B e D foram desafiadas aos 30 dias de vida com SG. Às 6 horas pós-infecção (6 hpi) e 1, 3 e 5 dias pós-infecção (dpi), três aves/grupo foram eutanasiadas para amostragem. A população de linfócitos T γδ foi avaliada por imuno-histoquímica em tonsilas cecais e fígado; citocinas foram quantificadas por RT-qPCR em tempo real em tonsilas cecais e baço e amostras de sangue para análises bioquímicas séricas. As lesões macroscópicas foram mais intensas nas aves do grupo D, a partir do 3º dpi, em comparação com as aves do grupo B. As contagens bacterianas no baço e fígado tiveram maiores quantidades nas aves do grupo D no 3° e 5° dpi. Após o 6° dpi, as aves do grupo D começaram a sucumbir ao tifo aviário, diferente das aves do grupo B, que não apresentaram nenhuma mortalidade. Aves do grupo B tiveram maiores quantidades das proteínas ... / The fowl typhoid is a systemic disease of chickens caused by Salmonella enteric subsp. enteric serovar Gallinarum biovar Gallinarum. This bacterium is highly pathogenic for chickens at any age, causing mortality even in adult birds. The progress of clinical signs differs among different lines of chickens. White lines of chickens are considered resistant and hardly mortality is observed. Chickens of brown lines are more susceptible and develop severe clinical signs with high mortality rates. The aim of this study was to evaluate the development of the disease and γδ T cells influx during the infection with SG in different varieties of layer-hens. In this study, 50 commercial layer-hens of white lines were used and 60 commercial layer-hens of brown lines were divided into 4 groups: group A (control for white layers), group B (infected white layers), group C (control for brown layers) and group D (infected brown layers). Chickens in groups B and D were challenged at 30 days-old with SG. At 6 hours post-infection (6 hpi) and 1, 3 and 5 days post-infection (dpi), three hens per group were sacrificed for sampling. The population of γδ T cells was evaluated by immunohistochemistry in caecal tonsils and liver; cytokines were quantified by real time RT-qPCR in caecal tonsils and spleen and samples of serum were used for biochemistry analysis. The macroscopic lesions were more intense in the hens of group D, at 3 dpi, in comparation with the group B. The bacterial numbers in spleen and liver from chickens in the group D were higher at 3 and 5 dpi. After 6 dpi, the mortality caused by fowl typhoid, began in group D. Differently, group B had no mortality. The group B had higher amounts of the proteins ceruloplasmin, albumin and α1- acid glycoprotein, in comparation to group D, but did not show statistical difference (p>0.05). The protein levels PM=99.000 Da, PM=90.000 Da and transferrin were significantly higher in group B (p<0.05) at ...

Made available in DSpace on 2014-06-11T19:27:57Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-18Bitstream added on 2014-06-13T19:57:05Z : No. of bitstreams: 1 penhafilho_rac_me_jabo.pdf: 391172 bytes, checksum: 766b9bf2041c86185eae35cbd749e2ac (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Salmonella Gallinarum (SG) causa o Tifo Aviário, uma doença caracterizada por alta mortalidade e morbidade em aves. Salmonella Enteritidis (SE) é uma salmonela paratífica, capaz de acometer aves e mamíferos. Carne de aves e ovos são as principais fontes de transmissão de SE, causando doença transmitida por alimentos em humanos. O controle destas bactérias nas criações avícolas é feito através da combinação de medidas sanitárias e a vacinação das aves. As vacinas vivas mostram-se melhores do que as inativadas para combater esses sorotipos, no entanto, a proteção contra SE, é parcial. A cepa SG cobS cbiA é incapaz de sintetizar vitamina B12. A ausência dessa substância prejudicou a sobrevivência da bactéria no organismo parasitado, causando atenuação na virulência. Neste trabalho, foram avaliadas a mortalidade e a infecção sistêmica causadas por SG cobS cbiA em comparação com uma cepa selvagem de SG. Também foi avaliado seu potencial vacinal contra SG e SE em aves de postura e sua utilização para impedir a colonização cecal por SE em pintinhos de corte de um dia. As aves de postura foram vacinadas com uma dose aos cinco dias, ou com duas doses aos cinco e vinte e cinco dias de vida e foram desafiadas com as respectivas cepas de SG e SE aos 45 dias de vida. As aves que receberam tanto uma quanto duas doses da cepa vacinal foram parcialmente protegidas contra SG. A proteção contra SE foi significativa no grupo de aves que recebeu duas doses de SG cobS cbiA. Porém, a inoculação de SG cobS cbiA em pintinhos com um dia de vida não impediu a colonização do ceco por SE. A cepa SG cobS cbiA demonstrou ter potencial vacinal contra SG e SE. / Salmonella Gallinarum (SG) causes Fowl Typhoid, a disease caracterized by high mortality and morbidity rates in poultry. Salmonella Enteritidis (SE) is a paratyphoid salmonelae that infects birds and mammals. Poultry meat and eggs are the main sources of transmission of SE, causing foodborne disease in humans. The control of these bacterias inside the avian breeding sites is done by the combination of sanitary measures and poultry vaccination. Live vaccines have demonstrated greater efficacy on the protection of poultry against these serovars than the killed vaccines, though, protection against SE is still partial. The strain SG cobS cbiA is uncapable to synthesize vitamin B12. The absence of this substance harmed the bacterial survival in the infected organism, causing attenuation of the virulence. On this work, the mortality and the sistemic infection by SG cobS cbiA were measured and compared with a wild strain of SG. It was also evaluated the potential use of the attenuated strain as a vaccine against SG and SE in laying hens and its utilization to prevent the colonization of the ceca by SE on 1-day-old chickens. The laying hens were vaccinated with one dose at 5- day-old, or with two doses at 5 and 25-day-old and were challenged at 45-day-old with the respective strain of SG or SE. The vaccination either with one or two doses was able to protect the birds against challenge with SG. The administration of two doses of SG cobS cbiA protected the laying hens against SE. Although, the inoculation of SG cobS cbiA by oral gavage on newly hatched chicks was unable to prevent the colonization of the ceca by SE. The protection confered by the strain SG cobS cbiA demonstrated its potential to be used as a vaccine.

Submitted by ANNY LUCIA DEL PILAR CELIS ESTUPIÑAN (annycelismvz@gmail.com) on 2016-09-21T02:37:36Z No. of bitstreams: 1 dissertação_anny final.pdf: 1389696 bytes, checksum: d3ced47a06c0e72bc76157c5c15980a8 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-09-22T20:57:08Z (GMT) No. of bitstreams: 1 celisestupinan_alp_me_jabo.pdf: 1389696 bytes, checksum: d3ced47a06c0e72bc76157c5c15980a8 (MD5) / Made available in DSpace on 2016-09-22T20:57:08Z (GMT). No. of bitstreams: 1 celisestupinan_alp_me_jabo.pdf: 1389696 bytes, checksum: d3ced47a06c0e72bc76157c5c15980a8 (MD5) Previous issue date: 2016-04-25 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Salmonella Gallinarum (SG) é o agente etiológico do tifo aviário (TA), uma doença sistêmica grave responsável por perdas econômicas para a indústria avícola em todo o mundo. TA foi considerado sob controle no Brasil e em países desenvolvidos. No entanto, nos últimos anos, inúmeros surtos dessa enfermidade têm sido identificados em lotes de aves de vários estados do Brasil. Com intuito de investigar fatores que pudessem ajudar a compreender a epidemiologia destes surtos, o presente estudo foi realizado. Foram avaliadas: (i) as possíveis alterações na patogenicidade de uma estirpe de SG isolada de um dos surtos recentes de TA, para as aves de linhagens comerciais utilizadas atualmente no Brasil; (ii) as possibilidades de transmissão de SG por via vertical e durante a incubação de ovos; (iii) a influência do uso antimicrobianos na persistência de SG na ave e consequente transmissão vertical; (iv) os perfis genéticos das estirpes isoladas anteriormente e, recentemente, por PFGE. No presente estudo, aves de linhagens mais suscetíveis infectadas por SG apresentaram alterações patológicas de maior intensidade e altas taxas de mortalidade, enquanto que as aves de linhagens mais resistentes apresentaram a mortalidade e sinais clínicos de forma mais branda. No entanto, foram capazes de manter SG por períodos mais longos que as aves de linhagens susceptíveis. SG não foi recuperada dos ovos produzidos por aves suscetíveis ou resistentes. A transmissão vertical não foi observada, embora aves recém-eclodidas foram infectadas por contato durante a incubação. Antibióticoterapia foi eficaz na redução da mortalidade, mas não foi capaz de eliminar a infecção e nem favoreceu a transmissão de SG via ovo. Estirpes de SG exibiram perfis genéticos muito semelhantes, sugerindo que eles vêm circulando nos lotes brasileiros há mais de 20 anos. Falhas em componentes do programa de biossegurança, provavelmente, podem ser responsáveis pela propagação FT no Brasil. / Salmonella Gallinarum (SG) causes fowl typhoid (FT) a severe systemic disease responsible for economic losses to the poultry industry worldwide. FT was considered under control in Brazil and in developed countries. Nonetheless, in recent years has been identified on farms in several states of Brazil. In order to investigate the epidemiological reasons behind this large FT outbreak, the present study was carried out to assess: (i) possible changes in the patogenicity of a strain of SG isolated from a recent outbreak to chickens of white and brown lines of layers; (ii) transmission through eggs and hatching; (iii) the interference of antibiotic to the persistence of SG in the bird and to vertical transmission; (iv) the genetic profiles of strains isolated previously and recently by PFGE. Susceptible lines showed extensive pathological changes and high mortality rates, whereas in resistant lines mortality and clinical signs were almost absent. Although, they could maintain SG for longer periods than the susceptible lines did. SG was not recovered from any egg laid by birds from susceptible or resistant either. Vertical transmission was not observed although newborn chicks were infected due the contact during incubation. Antibiotic therapy was effective at reducing mortality but was not able to clear the infection and neither to favour vertical transmission. Strains did exhibit very similar genetic profiles, suggesting they have been circulating in Brazilian flocks for more than 20 years. Failures in components of biosecurity programs, probably, would be the responsible for the FT spread in Brazil. / CNPq: 190778/2013-0

Orientador: Oliveiro Caetano Freitas Neto / Coorientador: Angelo Berchieri Junior / Banca: Nilce Maria Soares / Banca: Rafael Antonio Casarin Penha Filho / Resumo: Salmonella Gallinarum (SG) é o agente etiológico do tifo aviário (TA), uma doença sistêmica grave responsável por perdas econômicas para a indústria avícola em todo o mundo. TA foi considerado sob controle no Brasil e em países desenvolvidos. No entanto, nos últimos anos, inúmeros surtos dessa enfermidade têm sido identificados em lotes de aves de vários estados do Brasil. Com intuito de investigar fatores que pudessem ajudar a compreender a epidemiologia destes surtos, o presente estudo foi realizado. Foram avaliadas: (i) as possíveis alterações na patogenicidade de uma estirpe de SG isolada de um dos surtos recentes de TA, para as aves de linhagens comerciais utilizadas atualmente no Brasil; (ii) as possibilidades de transmissão de SG por via vertical e durante a incubação de ovos; (iii) a influência do uso antimicrobianos na persistência de SG na ave e consequente transmissão vertical; (iv) os perfis genéticos das estirpes isoladas anteriormente e, recentemente, por PFGE. No presente estudo, aves de linhagens mais suscetíveis infectadas por SG apresentaram alterações patológicas de maior intensidade e altas taxas de mortalidade, enquanto que as aves de linhagens mais resistentes apresentaram a mortalidade e sinais clínicos de forma mais branda. No entanto, foram capazes de manter SG por períodos mais longos que as aves de linhagens susceptíveis. SG não foi recuperada dos ovos produzidos por aves suscetíveis ou resistentes. A transmissão vertical não foi observada, embora a... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Salmonella Gallinarum (SG) causes fowl typhoid (FT) a severe systemic disease responsible for economic losses to the poultry industry worldwide. FT was considered under control in Brazil and in developed countries. Nonetheless, in recent years has been identified on farms in several states of Brazil. In order to investigate the epidemiological reasons behind this large FT outbreak, the present study was carried out to assess: (i) possible changes in the patogenicity of a strain of SG isolated from a recent outbreak to chickens of white and brown lines of layers; (ii) transmission through eggs and hatching; (iii) the interference of antibiotic to the persistence of SG in the bird and to vertical transmission; (iv) the genetic profiles of strains isolated previously and recently by PFGE. Susceptible lines showed extensive pathological changes and high mortality rates, whereas in resistant lines mortality and clinical signs were almost absent. Although, they could maintain SG for longer periods than the susceptible lines did. SG was not recovered from any egg laid by birds from susceptible or resistant either. Vertical transmission was not observed although newborn chicks were infected due the contact during incubation. Antibiotic therapy was effective at reducing mortality but was not able to clear the infection and neither to favour vertical transmission. Strains did exhibit very similar genetic profiles, suggesting they have been circulating in Brazilian flocks for more than 20 years. Failures in components of biosecurity programs, probably, would be the responsible for the FT spread in Brazil / Mestre

Orientador: Angelo Berchieri Junior / Banca: Fabiana Silva Lima / Banca: Ana Maria Iba Kanashiro / Banca: Oswaldo Durval Rossi Junior / Banca: Luiz Augusto do Amaral / Resumo: A Salmonella Pullorum (SP) é muito semelhante à Salmonella Gallinarum (SG), agentes da Pulorose e Tifo aviário, respectivamente, sendo responsáveis por perdas econômicas no setor avícola. São salmonelas de composição antigênica similar e a distinção de ambas tem sido baseada em provas bioquímicas. Entretanto, este procedimento é laborioso e o surgimento de estirpes com comportamento bioquímico atípico tem estimulado a procura por outros métodos de diagnóstico, como os testes moleculares. No presente estudo, analisou-se o método descrito na literatura envolvendo o gene rfbS em conjunto com testes desenvolvidos com base nos genes speC e speF. O gene rfbS codifica a enzima que atua na parede celular de bactérias e tem sido utilizado para diferenciar SP e SG. Com o propósito de padronizar a PCR para ser utilizada na rotina laboratorial, empregou-se dois métodos de extração de DNA e diferentes concentrações de reagentes. Entretanto, tendo em vista a dificuldade de padronização encontrada desde o início, foi concomitantemente desenvolvida a PCR para os genes speC e speF. Estes dois últimos estão relacionados com a produção da enzima ornitina-descarboxilase, a qual é ativa em SP e inativa em SG. Após testes inicias, foi possível padronizar a PCR do gene speC com posterior utilização da técnica de tratamento enzimático com a enzima de restrição Eco RI. Tanto para o gene rfbS quanto para os genes speC e speF, os resultados encontrados permitiram a diferenciação de 13 amostras de SP e 20 de SG isoladas no Brasil e duas cepas ATCC. Sendo assim, as ações sanitárias e a tomada de decisão no campo podem ser conduzidas de maneira rápida e segura. / Abstract: Salmonella Pullorum (SP) is very similar to Salmonella Gallinarum (SG). They are respectively agents of Pulorosis and Avian Typhoid, both diseases responsible for economic losses to poultry production. Due to the fact that both salmonellas have similar antigenic composition, their differentiation has been based in biochemical tests. However, this fact that this kind of procedure is very troublesome and the occurence of strains showing atypical behavior have stimulated the search for others diagnostic methods, such as molecular tests. In the present study, a method described in the literature using gene rfbS was analyzed together with tests developed based on genes speC and speF. Gene rfbS encodes an enzyme that acts on the cell wall of bacteria and has been used in the differentiation between SP and SG. In order to standardize the PCR procedure to be used in laboratory routine, two methods for DNA extraction were used, as well as different concentrations of the reagents. However, due to the difficulty in the standardization observed from the beginning of the study, a PCR procedure was developed for genes speC and speF. These genes are related to the production of the enzyme ornithine-descarboxilase, active in SP and inactive in SG. After the initial tests, PCR of gene speC was standardized, and later on it was coupled with the enzymatic treatment with restriction enzyme Eco RI. Results obtained for gene rfbS as well as for genes speC and speF enabled differentiation of 13 SP and 20 SG strains isolated in Brazil and two strains ATCC. So, the sanitary actions and the decisions in the livestock can to be conduced with safety and rapidity. / Doutor

This project was undertaken to establish whether the Onderstepoort Biological Products Fowl Typhoid (OBPft) vaccine registered as an injectable vaccine was effective and safe when administered orally to commercial layers. Its efficacy and duration of protection were compared to the intramuscular injectable route. Commercial brown layer hens were used as they were found to be highly susceptible to Salmonella gallinarum infections. In the safety trial birds were euthanased at timed intervals spanning 4-weeks post vaccination. Necropsies were performed and samples were taken and tested. No clinical signs or mortalities could be attributed to the OBPft vaccine. No active shedding of the vaccine strain could be detected. Slight pathological changes were noted with both routes of vaccination; however these changes were transient, returning to normal within the observation period. The injected group showed a better serological response with the serum agglutination test than the orally vaccinated groups. In the duration of protection trial the two routes of vaccination were compared, the birds were challenged at three 8-week intervals post vaccination. All the unvaccinated birds died. The protection offered to the vaccinated groups was good when birds were challenged 8 and 16-weeks after vaccination. However, this dipped steeply by the challenge 24-weeks post vaccination. Statistically (ANOVA, p<0.05) it was found that there was no significant difference between the protection offered by either the oral or injected route of vaccination with the OBPft vaccine. / Dissertation (MSc (Veterinary Science))--University of Pretoria, 2006. / Production Animal Studies / unrestricted

<p>The  Pakistan  poultry  industry  has  developed  into  the  11thlargest  poultry  industry  in  the world  and  poultry  products  provide  high-quality  and  affordable  protein  sources  to  communities throughout the country. However, <em>Salmonella </em>Gallinarum, the etiological agent for fowl typhoid, is  endemic  in  Pakistan  with  infections  leading  to  high  mortality  and  substantial  economic  loss. Currently, <em>Salmonella </em>Gallinarum  infectionsin  Pakistan  poultry  are  controlled  with  antibiotics. The continued emergence of antibiotic resistance, however, has led to global initiatives to reduce the  use  of  antibiotics  in  both  human  and  veterinary  medicine.  Concurrently,  the  Pakistan government  recently  introduced  new  national  policies  that  limit  the  use  of  antibiotics  for performance  in  livestock  and  poultry  production.  As  such,  controlling  bacterial  infections  in poultry  without  increasing  the  likelihood  of  antibiotic use could  ensure  the  sustainability  of Pakistan  poultry  production  without  posing  risks  to  public  health.  Toward  this  end,  we hypothesized that <em>Salmonella</em> Gallinarum infections inchickens could be prevented or otherwise controlled through the use of phages. To test this hypothesis, wastewater samples were collected from Lahore, Pakistan and different cities of Indiana, US and processed to isolate bacteriophages. The  phages  were  characterized  in  terms  of  morphology,  host  spectra,  lytic  capacity,  genomic sequencing,  and  survivability  in  different  environments. Transmission  electron  microscopy showed these phages belonged to myoviridae (n = 5) and podoviridae (n = 1) families. Spectrum analysis  revealed  that  each  phage  lysed  at  least  8  out  of  10  different  strains  of <em>Salmonella </em>Gallinarum and significantly reduced (P < 0.05) <em>Salmonella </em>Gallinarum when co-cultured in liquid medium with the bacterium. Stability of the phages was tested insimulated gastric fluid (SGF; pH= 2.5) andsimulated intestinal fluid (SIF; pH~6.8). Results showed that phage concentrationswere reduced to undetectable levels when exposed to SGF for more than 5 minutes. However, exposure to SIF did not result in appreciable reductions in phage concentrations. To mitigate potential effects of  gastric  environments,  phages  were  encapsulated  using  a  sodium  alginate-based  method.  In contrast  to  unprotected  phages,  encapsulated  phages  remained  viable  (~100%)  after  30  minutes exposure to SGF. Additionally, encapsulation efficiencies ranged between 90-99%. Encapsulated phages were sequentially incubated in SGF (30 minutes) and SIF(120 minutes) to determine the rate  of  release  of  the  phages  from  capsules. All  phages  were  released from  capsules after  60 minutes  of  exposureto  SIF. To  determine  if  the  phages  effectively  controlled <em>Salmonella </em>Gallinarum infections in chickens, 100, day-old Jumbo Cornish Rock Cross birds were randomly assigned  to  one  of  four  treatments:  1)  Control 1  (bacterial  challenge,  no  phage  treatment);  2) Control 2 (no phage or bacterial challenge); 3) challenged with SalmonellaGallinarum and treated with  unprotected  phages;  and  4)  challenged  with <em>Salmonella</em> Gallinarum  and  treated  with encapsulated phages. At7 d of age, chicks receiving the bacterial challenge were administered 5 X106CFU (500 μL) of <em>Salmonella</em> Gallinarum. For birds in phage treatment groups, the phages were administered (500 uL; 5 X108 PFU/mL or g) at 0, 12, and 24 hours post-challenge. Six birds from each group were euthanized at 1, 2, and 4 days post-challenge (dpc) and cecal SalmonellaGallinarum  concentrations  were  quantified.  At 1  dpc, birds  treated  with  unprotected  and encapsulated  phages  had significantly lower (P  <  0.05) SalmonellaGallinarum concentrations(4.36 ± 0.20and 5.05 ± 0.22 logCFU/g, respectively) than those found in untreated birds (5.71 ± 0.13). Likewise,  at4  dpc, <em>Salmonella </em>Gallinarum concentrationsin  ceca  of  birds  treated  with encapsulated and unprotected phages were significantly lower (P < 0.05; 3.26 ± 0.62 and 4.02 ± 0.15 log  CFU/g,  respectively)  than  those  found  in untreated  birds(4.65  ±  0.08log  CFU/g). A second trial was conducted with higher challenge doses (1 mL at 1× 109CFU) and an additional treatment including a mixture (1:1) of unprotected and encapsulated phages. At1dpc, <em>Salmonella</em> Gallinarum concentrations  in the ceca  of  birds  treated  with unprotected  phages,  encapsulated phages, and a mixture of unprotected  and encapsulated phages  were significantly lower(4.28 ± 0.11, 3.72 ± 0.40, and 3.81 ± 0.36log CFU/g, respectively) than found in those of untreated birds (5.26 ± 0.19log CFU/g). At 2 dpc, concentrations of<em> Salmonella </em>Gallinarumin the ceca of birds treated  with  unprotected,  encapsulated,  and  a mixture  of  unprotected  and  encapsulated  phages were significantly  lower  (P  <  0.05; 4.31  ±0.53, 3.96  ±0.61,  and 4.38  ±  0.44logCFU/g, respectively) than those found in the ceca of untreated birds (5.72 ± 0.27logCFU/g).However, no significant differences were found in concentrations of <em>Salmonella</em> Gallinarum in the ceca of birds treated with encapsulated phages versus those treated with unprotected phagesor a mixture of   encapsulated   and   unprotected   phages.   Similarly,   at   4   dpc, <em>Salmonella </em>Gallinarum concentrations in the ceca  of  birds  treated  with unprotected  phages, encapsulated  phages,  and  a mixture of unprotected and encapsulated phages were significantly lower (3.17 ± 0.45, 3.56 ± 0.51, and 3.81 ± 0.54log CFU/g, respectively) than found in those of untreated birds (5.79 ± 0.08log CFU/g). At  7  d  post-challenge,  concentrations of <em>Salmonella</em> Gallinarum in  the  ceca  of  birds treated  with mixture  of  unprotected  and  encapsulated phages(2.40  ±  0.55log  CFU/g)  were significantly lower (P  <  0.05) than  those  found  in the ceca  of  untreated  birds(7.08  ±  0.19log CFU/g). Similarly,  concentrations of<em> Salmonella</em> Gallinarum  in the  ceca of  birds  treated  with encapsulated and unprotected phages were significantly lower (P < 0.05; 4.29 ± 0.39and 4.60 ± 0.37 log  CFU/g,  respectively)  than  those  found  in  untreated  birds.  Taken  together,  these  data indicate that <em>Salmonella </em>Gallinarum infections could be controlled with phage-based treatments. Additionally, the use of a mixture of unprotected and encapsulated phages may be more effective, presumably  by  allowing  unprotected  phages  to  act  immediately  in  the  proximal  gastrointestinal tract  (GIT;  e.g.,  crop)  with  encapsulated  phages  having  greater  activity  once  released  from capsules in the distal small intestine. While no deleterious effects of the phages were observed on the chickens themselves, continuing studies should more comprehensively assess host-response to phage treatment including potential impact on microbial communities throughout the chicken GIT.</p>