Resumo
Objetivou-se avaliar o efeito dos anticorpos (ACs) maternos sobre resposta imune humoral induzida pela vacinação em bezerros Holandeses. Bezerros foram distribuídos aleatoriamente em quatro grupos: G1 - vacinados no D14 e D44 (n=6); G2 - vacinados no D90 e D120 (n=5); G3 - vacinados no D180 e D210 (n=8); controle: não vacinado (n=5). Utilizaram-se 5mL de vacina comercial (Cattle Master Gold FP5+L5® - Zoetis, Brasil), por via subcutânea. Foi realizada vírus neutralização (VN) no momento da vacinação, booster e 30 dias após a revacinação. Não foram observadas diferenças entre controle e G1 ou G2 para a frequência de soropositivos ou títulos de ACs contra os vírus respiratórios (P≥0,05). G3 apresentou maior produção de ACs em relação ao controle para BoHV-1 (P<0,01), BRSV (P<0,01) e BPIV-3 (P=0,02) após o booster (D240). A análise no tempo também demonstrou aumento nos títulos de ACs no G3 (P≤0,05). O perfil clínico revelou broncopneumonia apenas no grupo controle (n=4/5) entre 80-135 dias de vida. A imunidade colostral e a vacinal apresentaram perfis inversamente proporcionais, com maior produção de ACs aos seis meses de idade. Devido à precocidade da doença respiratória, estudos complementares são necessários para esclarecer o papel da resposta imune celular na vacinação diante dos ACs maternos.(AU)
This research aimed to evaluate the effect of colostral antibodies (ABs) on the humoral immune response induced by vaccination in Holstein calves. Twenty-four calves were randomly assigned into four groups: G1 - vaccinated on D14 and D44 (n= 6); G2 - on D90 and D120 (n= 5); G3 - on D180 and D210 (n= 8); Control: unvaccinated (n= 5). Commercial vaccine (Cattle Master Gold FP5+L5® - Zoetis, Brazil) was administered subcutaneously (5mL). Virus neutralization test (VN) was performed at the time of vaccination, booster and 30 days after booster to determine AB titers. No differences were observed between control and G1 or G2 for seropositive frequencies and ABs titers (P≥ 0.05). G3 showed higher AB production than control for BoHV-1 (P< 0.01), BRSV (P< 0.01) and BPIV-3 (P= 0.02) after booster (D240). Overtime analysis also exhibited increase in AB titers in G3 (P≤ 0,05). Bronchopneumonia was identified in the control group (n= 4/5) between 80-135 days of life. The colostral and vaccinal immunity presented inversely proportional profiles, with higher production of ABs at 6 months of age. Due to the precocity of respiratory disease further studies are required to clarify the role of cellular immune response to vaccination in face of maternal ABs.(AU)
Assuntos
Animais , Bovinos , Broncopneumonia/veterinária , Vacinação , Imunidade Humoral , Imunidade Materno-Adquirida , Doenças Respiratórias/veterináriaResumo
Objetivou-se avaliar o efeito dos anticorpos (ACs) maternos sobre resposta imune humoral induzida pela vacinação em bezerros Holandeses. Bezerros foram distribuídos aleatoriamente em quatro grupos: G1 - vacinados no D14 e D44 (n=6); G2 - vacinados no D90 e D120 (n=5); G3 - vacinados no D180 e D210 (n=8); controle: não vacinado (n=5). Utilizaram-se 5mL de vacina comercial (Cattle Master Gold FP5+L5® - Zoetis, Brasil), por via subcutânea. Foi realizada vírus neutralização (VN) no momento da vacinação, booster e 30 dias após a revacinação. Não foram observadas diferenças entre controle e G1 ou G2 para a frequência de soropositivos ou títulos de ACs contra os vírus respiratórios (P≥0,05). G3 apresentou maior produção de ACs em relação ao controle para BoHV-1 (P<0,01), BRSV (P<0,01) e BPIV-3 (P=0,02) após o booster (D240). A análise no tempo também demonstrou aumento nos títulos de ACs no G3 (P≤0,05). O perfil clínico revelou broncopneumonia apenas no grupo controle (n=4/5) entre 80-135 dias de vida. A imunidade colostral e a vacinal apresentaram perfis inversamente proporcionais, com maior produção de ACs aos seis meses de idade. Devido à precocidade da doença respiratória, estudos complementares são necessários para esclarecer o papel da resposta imune celular na vacinação diante dos ACs maternos.(AU)
This research aimed to evaluate the effect of colostral antibodies (ABs) on the humoral immune response induced by vaccination in Holstein calves. Twenty-four calves were randomly assigned into four groups: G1 - vaccinated on D14 and D44 (n= 6); G2 - on D90 and D120 (n= 5); G3 - on D180 and D210 (n= 8); Control: unvaccinated (n= 5). Commercial vaccine (Cattle Master Gold FP5+L5® - Zoetis, Brazil) was administered subcutaneously (5mL). Virus neutralization test (VN) was performed at the time of vaccination, booster and 30 days after booster to determine AB titers. No differences were observed between control and G1 or G2 for seropositive frequencies and ABs titers (P≥ 0.05). G3 showed higher AB production than control for BoHV-1 (P< 0.01), BRSV (P< 0.01) and BPIV-3 (P= 0.02) after booster (D240). Overtime analysis also exhibited increase in AB titers in G3 (P≤ 0,05). Bronchopneumonia was identified in the control group (n= 4/5) between 80-135 days of life. The colostral and vaccinal immunity presented inversely proportional profiles, with higher production of ABs at 6 months of age. Due to the precocity of respiratory disease further studies are required to clarify the role of cellular immune response to vaccination in face of maternal ABs.(AU)
Assuntos
Animais , Bovinos , Broncopneumonia/veterinária , Vacinação , Imunidade Humoral , Imunidade Materno-Adquirida , Doenças Respiratórias/veterináriaResumo
Esta pesquisa avaliou a TIP e a dinâmica de anticorpos (ACs) específicos em bezerros naturalmente expostos aos agentes causadores da doença respiratória bovina (DRB). Foram selecionados 19 bezerros Holandeses alimentados com colostro proveniente de doadoras vacinadas para DRB. Amostras de soro foram obtidas antes e após a ingestão do colostro (48h) para a soroneutralização (SN). Os valores médios (log2) detectados após colostragem foram de 11,5±1,6 (BVDV), 8,8±1,3 (BoHV-1), 5,5±1,6 (BRSV) e 8,4±1,5 (BPIV-3). Cinco bezerros foram criados do nascimento aos 240 dias de vida, observando-se decréscimo nos títulos de ACs para BVDV, BoHV-1 e BPIV-3 ao longo do tempo (P≤0,001). As taxas de infecções detectadas entre o D14 e o D240 foram de 40% (2/5), 20% (1/5), 80% (4/5), e 60% (3/5), respectivamente, para BVDV, BoHV-1, BRSV e BPIV-3. A maioria dos bezerros manifestou broncopneumonia após as infecções virais. Os bezerros apresentaram ACs para todas as viroses às 48 horas de vida, porém os títulos adquiridos para o BRSV foram baixos. A susceptibilidade para as infecções variou de acordo com os níveis e a duração dos títulos de ACs maternos.(AU)
This research evaluated the PIT and the dynamics of specific antibody (Ab) for calves naturally exposed to the viral agents involved in Bovine Respiratory Disease (BRD). Nineteen Holstein calves fed colostrum from vaccinated donors for DRB. Serum samples were obtained before and after colostrum intake (48h) for serum neutralization (SN). Mean values (log2) detected after colostrum feeding were 11.5±1.6 (BVDV), 8.8 ±1.3 (BoHV-1) 5.5±1.6 (BRSV) and 8.4±1.5 (BPIV-3). Five calves were raised from birth to 240 days of life and presented a decrease in Ab titers for BVDV, BoHV-1 and BPIV-3 over time (P≤ 0.001). Infection rates from D14 to D240 were of 40% (2/5), 20% (1/5), 80% (4/5) and 60% (3/5), respectively for BVDV, BoHV-1, BRSV and BPIV-3. Most of the calves presented bronchopneumonia after seroconversion to the virus. Calves presented Ab for all viruses at 48 hours of life, however BRSV Ab titer were low. Levels and persistence of maternal antibody titers determined the susceptibility to viral infections.(AU)
Assuntos
Animais , Bovinos , Bovinos/imunologia , Imunização Passiva/veterinária , Viroses/imunologia , Herpesvirus Bovino 1Resumo
Esta pesquisa avaliou a TIP e a dinâmica de anticorpos (ACs) específicos em bezerros naturalmente expostos aos agentes causadores da doença respiratória bovina (DRB). Foram selecionados 19 bezerros Holandeses alimentados com colostro proveniente de doadoras vacinadas para DRB. Amostras de soro foram obtidas antes e após a ingestão do colostro (48h) para a soroneutralização (SN). Os valores médios (log2) detectados após colostragem foram de 11,5±1,6 (BVDV), 8,8±1,3 (BoHV-1), 5,5±1,6 (BRSV) e 8,4±1,5 (BPIV-3). Cinco bezerros foram criados do nascimento aos 240 dias de vida, observando-se decréscimo nos títulos de ACs para BVDV, BoHV-1 e BPIV-3 ao longo do tempo (P≤0,001). As taxas de infecções detectadas entre o D14 e o D240 foram de 40% (2/5), 20% (1/5), 80% (4/5), e 60% (3/5), respectivamente, para BVDV, BoHV-1, BRSV e BPIV-3. A maioria dos bezerros manifestou broncopneumonia após as infecções virais. Os bezerros apresentaram ACs para todas as viroses às 48 horas de vida, porém os títulos adquiridos para o BRSV foram baixos. A susceptibilidade para as infecções variou de acordo com os níveis e a duração dos títulos de ACs maternos.(AU)
This research evaluated the PIT and the dynamics of specific antibody (Ab) for calves naturally exposed to the viral agents involved in Bovine Respiratory Disease (BRD). Nineteen Holstein calves fed colostrum from vaccinated donors for DRB. Serum samples were obtained before and after colostrum intake (48h) for serum neutralization (SN). Mean values (log2) detected after colostrum feeding were 11.5±1.6 (BVDV), 8.8 ±1.3 (BoHV-1) 5.5±1.6 (BRSV) and 8.4±1.5 (BPIV-3). Five calves were raised from birth to 240 days of life and presented a decrease in Ab titers for BVDV, BoHV-1 and BPIV-3 over time (P≤ 0.001). Infection rates from D14 to D240 were of 40% (2/5), 20% (1/5), 80% (4/5) and 60% (3/5), respectively for BVDV, BoHV-1, BRSV and BPIV-3. Most of the calves presented bronchopneumonia after seroconversion to the virus. Calves presented Ab for all viruses at 48 hours of life, however BRSV Ab titer were low. Levels and persistence of maternal antibody titers determined the susceptibility to viral infections.(AU)
Assuntos
Animais , Bovinos , Bovinos/imunologia , Imunização Passiva/veterinária , Viroses/imunologia , Herpesvirus Bovino 1Resumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detect
Resumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detected in blood samples of animals in both groups taken on days 1st, 3rd, 5th, 7th, 10th and 14th. At the end of day 14th, BRSV antibody titer increased in 9 out of 10 animals (90%) in testing group that were given Umckaloabo/EPs® 7630 liquid extract while one of them (10%) showed no variability. BRSV antibody titer increased in 6 out of 10 animals (60%) in control group while it decreased in one of them (10%) and 3 of them (30%) showed no variability.[...]
Assuntos
Animais , Bovinos , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/veterinária , Pelargonium/química , Sistema Respiratório/fisiopatologia , Vírus Sincicial Respiratório Bovino , Extratos VegetaisResumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detected in blood samples of animals in both groups taken on days 1st, 3rd, 5th, 7th, 10th and 14th. At the end of day 14th, BRSV antibody titer increased in 9 out of 10 animals (90%) in testing group that were given Umckaloabo/EPs® 7630 liquid extract while one of them (10%) showed no variability. BRSV antibody titer increased in 6 out of 10 animals (60%) in control group while it decreased in one of them (10%) and 3 of them (30%) showed no variability.[...](AU)
Assuntos
Animais , Bovinos , Sistema Respiratório/fisiopatologia , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/veterinária , Vírus Sincicial Respiratório Bovino , Pelargonium/química , Extratos VegetaisResumo
O objetivo deste estudo foi avaliar os aspectos clínicos, a eficiência produtiva, reprodutiva, a resposta imune inata e humoral em fêmeas da raça Holandesa persistentemente infectadas (PI) com BVDV. Para tanto, foram selecionadas 25 PI´s por meio do ELISA antígeno, das quais oito eram bezerras 12 meses; seis novilhas entre 13 e 24 meses; e onze animais de 25 a 36 meses de idade. O grupo não infectado (NI) foi composto por fêmeas negativas com faixas etárias pareadas às PIs. Em geral, as fêmeas PIs apresentaram maior frequência de diarreia (P=0,012) e Doença Respiratória Bovina (DRB) (P=0,004), especialmente àquelas entre 25 a 36 meses de idade. As PIs apresentaram maior concentração sérica de haptoglobina (P=0,017). As vacas NI´s produziram mais leite (8-12 litros) do que as PIs (P0.011). A contagem de células somáticas (CCS) foi maior para as vacas PI´s em relação NI´s durante a lactação (P0,066). A média de CCS observada foi de 0,2-0,5 x 105 (células/mL) e 2,0-10,5 x 105 (células/mL) nos grupos PI e NI, respectivamente. A idade na primeira inseminação (P=0,001) e o número de inseminação necessário para a primeira prenhez foi maior para PI do que nas novilhas NI´s (P=0,051). Na avaliação hematológica, as PI´s apresentaram menores valores de hemoglobina (P=0,098), hematócrito (P=0,084), hemoglobina corpuscular média (P=0,092), plaquetas (P=0,040), plaquetócrito (P=0,059) e linfócitos (número absoluto P=0,075; relativo P=0,092) em relação às NI´s. Em contraste, a porcentagem de monócitos foi maior em PI do que animais NI (P=0,014). Em geral, a proporção (%) e a intensidade da fagocitose (MFI) para Staphylococcus aureus e Escherichia coli foram maiores nas PIs do que animais NI (P<0,079). A porcentagem de células que produziram espécies reativas de oxigênio (EROs) endógeno foi menor em PI do que animais de NI (P=0,005). Padrão semelhante foi observado na porcentagem de células que produziram EROs após estímulo com Staphylococcus aureus (P=0,000) ou Escherichia coli (P=0,000). Em contraste, a intensidade da produção de EROS basal foi maior nas PI´s do que nas NI´s (P=0,011). Um padrão semelhante foi observado para a intensidade da produção de EROs quando as células foram estimuladas com Staphylococcus aureus (P=0,011) ou Escherichia coli (P= 0,013). Por meio da soroneutralização, observou-se que os títulos médios dos anticorpos neutralizantes para as BVDV, BRSV e BoHV foram menor no grupo PI (P=0,000). No entanto, os títulos de anticorpos para BPIV-3 foram semelhantes entre os grupos (P=0,146). A proteína sérica total (PT) foi menor nas PI em relação as NI´s (P=0,021). As fêmeas PIs apresentaram maior frequência de diarreia e DRB, além da menor produção leiteira, diminuição da qualidade do leite e menor fertilidade. O leucograma demonstrou diminuição dos tipos celulares, exceto monócitos. No geral, houve resposta imune inata foi exacerbada nas fêmeas PIs, provavelmente pela menor eficiência na produção de EROs. Em relação ao sistema imune específico observou-se linfopenia e títulos nulos ou baixos de anticorpos neutralizantes contra as viroses respiratórias.
The aim of this study was to evaluate the clinical problems, the efficiency of production, reproduction, the innate and humoral immune response of Holstein heifers and cows persistently infected (PI) with BVDV. Therefore, 25 PI animals were selected using ELISA antigen of which, eight were heifers 12 months; six were heifers between 13 to 24 months; and eleven were animals from 25 to 36 months old. An uninfected group (NI) composed by negative females with same age of PI´s. We observed that PI´s presented more frequency of diarrhea (P=0.012) and Bovine Respiratory Disease (BRD) score (P=0.004), especially the animals from 25 to 36 months old.The PI´s showed higher concentration of haptoglobin (P=0.017). During the lactations the milk production from NI cows was higher (8 to 18,2 litters) than PI (P0.011). Somatic cells count (SCC) were higher for PI than NI cows across milk production (P0.066). The mean of SCC observed was 0,2-0,5 x105 (cells/mL) in NI group and 2,0-10,5 x105 (cells/mL) for PI cows. The age at first insemination (P=0.001) and number of insemination required for the first pregnancy was higher for PI than NI heifers (P=0.051). For hematological evaluation, PI´s showed lower hemoglobin (P=0,098), hematocrit (P=0,084), mean corpuscular hemoglobin (P=0,092), platelet (P=0,040), plateletcrit (P=0,059) and lymphocytes (absolute number P=0.092; relative P=0,075) than NI. In contrast, the percentage of monocytes was higher in PI than NI animals (P=0.014). In aggregate, the percent of phagocytic cells and the average phagocytic avidity (expressed as mean fluorescence intensity, MFI) for Staphylococcus aureus and Escherichia coli were higher in PI than NI animals (P< 0.079). The percentage of cells producing endogenous reactive oxygen species (ROS) activity was lower in PI than NI animals (P=0.005). A similar pattern was observed in the percentage of cells producing ROS after exposure to Staphylococcus aureus (P= 0.000) or Escherichia coli (P=0.000). In contrast, the value for endogenous ROS per cell activity (MFI) was higher in PI than NI animals (P=0.011). A similar pattern was observed for ROS MFI after stimulating with Staphylococcus aureus (P=0.011) or Escherichia coli stimulation (P=0.013). The median conventional SN titers for specific antibody recognizing BVDV, BRSV and BoHV-1 in serum were lower in PI than NI animals (P=0.000). The antibody titers for BPIV3 were similar between the groups animals (P=0,146). In aggregate, the total serum protein (TP) was lower in PI than NI cattle (P=0.021). In summary, PI heifers had more diarrhea, BRD, produced less milk, worst milk quality and poorer reproductive performance than NI cattle. Leukogram showed decreased cell types except monocytes. Overall, there was a higher endogenous level innate cell reactivity in PI heifers and cows than NI animals, probably because of the lower efficiency in ROS production. In relation to the specific immune system it appear that the PI animals were less efficient in clearance of antigens due to lower numbers of lymphocytes and related lower titers of specific antibody against respiratory viruses.
Resumo
A ocorrência de doença respiratória bovina (DRB) ocasionada por Mycoplasma bovis foi avaliada em vacas leiteiras em lactação de três rebanhos (A C) de alta produção localizados na mesorregião central oriental do estado do Paraná, sul do Brasil. Com o objetivo de determinar a etiologia de casos clínicos de doença respiratória em vacas em lactação, foi acompanhado por um período de nove meses o rebanho A que apresentou casos recorrentes de DRB em vacas no pós parto. Neste intervalo de tempo, para investigar a etiologia, foram coletados 12 swabs nasais de vacas com quadro clínico de DRB e 12 fragmentos de pulmão de vacas que morreram por DRB. Nos rebanhos B e C, os problemas respiratórios ocorreram de forma diferente. Vacas em pico de lactação apresentaram sinais clínicos agudos de DRB sob a forma de surto comprometendo vários animais simultaneamente. Para o diagnóstico etiológico da DRB foram coletadas amostras de swab nasal em vacas com sinais clínicos de problemas respiratórios agudos no rebanho B (n=20) e no rebanho C (n=9). Todas as amostras foram avaliadas por PCR / RT-PCR para avaliar a presença dos principais agentes etiológicos envolvidos em DRB incluindo Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, vírus respiratório sincicial bovino (BRSV), coronavírus bovino (BCoV), vírus da diarreia viral bovina (BVDV), alfaherpesvírus bovino 1 (BoHV-1) e vírus parainfluenza bovino 3 (BPIV-3). Secções pulmonares de vacas do rebanho A que morreram com BRD foram submetidas à análise histopatológica. Amplicon com tamanho esperado de 488 pb foi obtido por nested-PCR para M. bovis em 9 (75%) dos 12 fragmentos de tecido pulmonar obtidos no rebanho A. Destas, sete vacas apresentaram infecção singular por M. bovis enquanto duas vacas apresentavam infecção mista com P. multocida (n=1) e BVDV (n=1). Nas amostras de swabs nasais (n=12) coletadas do rebanho A, as reações de PCR / RT28 PCR foram positivas para M. bovis (n=3; 25%), P. multocida (n=4; 33,3%), M. haemolytica (n=3; 25%), BVDV (n=2; 16,6%) e BoHV-1 (n=1; 8,3%). Os tecidos pulmonares apresentaram alterações histopatológicas clássicas descritas nos casos de pneumonia por M. bovis em bovinos. Nas vacas do rebanho B foram identificadas apenas infecções com M. bovis (n = 8; 40%) e H. somni (n = 15; 75%). No rebanho C, M. bovis, H. somni e P. multocida foram identificados em swabs nasais de seis (66,6%), duas (22,2%) e três (33,3%) das vacas, respectivamente. Em ambos os rebanhos, nenhum dos outros micro-organismos envolvidos na etiologia de DRB e que foram incluídos nas análises moleculares foi identificado. M. bovis é considerado um micro-organismo fastidioso, com isso, o diagnóstico laboratorial é frequentemente negligenciado e a maioria dos casos clínicos de micoplasmose em bovinos jovens e adultos não é diagnosticada. Este estudo, que envolveu a análise dos principais micro39 organismos causadores de BRD, demonstrou a importância da infecção por M. bovis em vacas adultas em três rebanhos bovinos leiteiros de alta produção. Ressalta-se que, em um rebanho (A), a infecção apresentou-se de forma recorrente, com o surgimento de vários casos clínicos durante os nove meses de avaliação. Em contraposição, nos outros dois rebanhos (B e C) a BRD ocorreu na forma de surto de sinais clínicos respiratórios agudos. Os resultados apontam para a importância de incluir o diagnóstico etiológico de M. bovis em casos de DRB em animais adultos, especialmente em vacas no pós-parto e em vacas no pico lactacional.
The occurrence of bovine respiratory disease (BRD) caused by Mycoplasma bovis was investigated in lactating dairy cows from three high milk yield dairy cattle herds of the eastern central mesoregion of the Paraná state, southern Brazil. With the objective of determining the etiology of clinical cases of respiratory disease in lactating cows, the A herd that presented recurrent cases of DRB in postpartum cows was followed for a period of nine months. In this time interval were collected for determination of the etiology of BRD 12 nasal swabs and 12 lung tissues fragments of cows that died from BRD. Differently, in the other two farms (B and C) the respiratory symptoms in lactating cows, targeting cows at peak lactation, occurred in the form of an outbreak, so several cows presented acute cases of BRD simultaneously. For BRD diagnostic 29 nasal swabs samples were collected in cows with clinical signs of acute respiratory problem in farm B (n=20) and farm C (n=9). All samples were evaluated by PCR / RT-PCR for nucleic acid detection of the main BRD etiological agents including Mycoplasma bovis, Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, bovine respiratory syncytial virus (BRSV), bovine coronavirus (BCoV), bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoHV-1), and bovine parainfluenza virus 3 (BPIV-3). Pulmonary sections cows that died with BRD were submitted to histopathological analysis. Amplicon with 488 bp length was obtained in nested-PCR for M. bovis in 9 (75%) of the 12 lung tissue fragments obtained from farm A. Of these, seven cows presented M. bovis single infection while two cows had mixed infection with P. multocida (n=1) and BVDV (n=1). In nasal swabs samples (n=12) collected from farm A the PCR / RT-PCR reactions were positive for M. bovis (n=3; 25%), P. multocida (n=4; 33.3%), M. haemolytica (n=3; 25%), BVDV (n=2; 16.6%), and BoHV-1 (n=1; 8.3%). Pulmonary tissues showed classic histopathological changes described in cases of M. bovis pneumonia in cattle. Differently, in cows from farm B were identified only infections with M. bovis (n=8; 40%) and H. somni (n=15; 75%). In farm C the M. bovis, H. somni, and P. multocida were identified in nasal swabs of 6 (66.6%), 2 (22.2%), and 3 (33.3%) cows, respectively. In both herds, none of the other microorganisms involved in BRD included in the analysis were identified. M. bovis is considered a fastidious microorganism. Thus, the laboratory diagnosis is neglected and most clinical cases of mycoplasmosis in cattle are not diagnosed. This study, which involved the analysis of the main microorganisms causing BRD, demonstrated the importance of M. bovis infection in adult cows in three high milk yield dairy cattle herds. It is highlighted that in a herd (A) the infection occurred recurrently, with several cases during 9 months of evaluation. In contrast, in the two other herds (B and C) the BRD occurred as an outbreak of acute respiratory clinical signs. The results point to the importance of including the M. bovis diagnosis in cases of BRD in adult animals, especially in newly calved cows and cows at peak milk yield.
Resumo
As doenças respiratórias dos bovinos (DRB) afetam a produtividade ao comprometer a saúde e o bem-estar dos animais. Dessa forma, os objetivos dos estudos foram relacionados ao uso de protocolos vacinais e metafiláticos na redução da morbidade, além da participação de fatores de risco na ocorrência das DRB. Os estudos foram realizados em um confinamento comercial no noroeste de Minas Gerais. Foram avaliados ocorrência de lesões pulmonares, participação de agentes virais e bacterianos nas DRB, efeito de fatores de risco e de protocolos vacinais e metafiláticos na morbidade por DRB em bovinos machos, não castrados, com média de 20 meses de idade. Os protocolos metafiláticos com oxitetraciclina e tildipirosina a partir do risco de DRB foram eficientes em relação à morbidade e lesões pulmonares. Animais que receberam vacina contra agentes virais das DRB ao chegarem no confinamento tiveram 2,5 vezes menos chance de terem DRB comparado aos animais vacinados com dose-reforço antes da entrada. Observou-se que a vacinação no momento da entrada dos animais contra herpesvírus bovino tipo 1 (BoHV-1), vírus da diarreia viral bovina (BVDV tipo 1 e 2), vírus sincicial respiratório bovino (BRSV), vírus da parainfluenza bovina tipo 3 (BPIV-3), Mannheimia haemolytica e Pasteurella multocida é eficiente em reduzir a morbidade por DRB e interfere positivamente no rendimento de ganho em bovinos confinados. Portanto, o conhecimento de fatores de risco, dos agentes virais e bacterianos permite propor métodos de prevenção para essas doenças, melhorando o bem-estar animal e reduzindo as perdas econômicas.
The Bovine Respiratory Diseases (BRD) affect the productivity by compromising the health and welfare of cattle. Thus, the aim of these studies were related to the use of prophylactics and methaphylatics protocols to reduce morbidity of DRB, in addition to the participation of risk factors in the occurrence of BRD. The studies were carried out in a commercial feedlot in the northwest of Minas Gerais. Lung lesions occurence, the participation of viral and bacterial agents in DRB were evaluated, and verified the effect of risk factors, vaccine and methaphylatic protocols on mobidity of BRD, in uncastrated male bovine with a mean of 20 months of age. The methaphylatic protocols with oxitetracyclin and tildipirosin defined by BRD risk were efficient in relation to morbidity of DRB and lung lesions. Cattle wich were vaccinated against BRD viral agents on the entering of feedlot had 2.5 folds more risk of developing BRD, when compared with group that received booster before entry feedlot. It was observed that vaccination at the time of entry of animals against Bovine herpes virus 1 (BoHV-1), Bovine viral diarrhea vírus (BVDV), Bovine respiratory syncytial vírus (BRSV), Bovine parainfluenza type 3 virus, Mannheimia haemolytica and Pasteurella multocida is efficient to reduce morbidity of BRD and also has a positive impact in performance of feedlot cattle. Hence, the knowledge of the risk factors, of the viral and bacterial agents allows proposing methods to prevent these diseases and still improve animal welfare and reduce economic losses.
Resumo
Genomic fragments of the HN and L genes from Brazilian bovine parainfluenza 3 virus (bPIV-3) isolated as contaminants from cell cultures and clinical specimens were amplified by reverse transcription-polymerase chain reaction (RT-PCR), sequenced using specific degenerate primers and analyzed by phylogenetic comparison with reference strains of bPI3V. The Brazilian isolates revealed a high degree of genomic when compared to SF4/32 prototype strain, within the recently proposed genotype A of bPIV-3.
Resumo
O objetivo geral desta pesquisa foi avaliar a transferência de imunidade passiva e a sua influência na resposta vacinal para as viroses envolvidas na Doença Respiratória Bovina (DRB). Os dados obtidos nesta pesquisa estão apresentados em dois capítulos. Capítulo 1 - Objetivou-se avaliar a dinâmica de anticorpos (Acs) específicos para as viroses respiratórias e subpopulações de linfócitos em bezerros do nascimento aos 240 dias (d) de vida. Para tanto, acompanhou-se a transferência de imunidade passiva de Acs específicos para as viroses respiratórias em 19 bezerros, destes cinco foram selecionados para acompanhamento da dinâmica de Acs neutralizantes e subpopulações de linfócitos dos 14 aos 240d. O colostro fornecido era proveniente de vacas doadoras vacinadas. A análise da qualidade individual do colostro revelou índice Brix 21%, observando-se forte correlação desses valores com proteína total (r= 0,942 e P= 0,001). Após 48 horas da ingestão do colostro, pôde-se observar soroconversão dos 19 animais (100%) para os agentes virais envolvidos na DBR. As medianas (Log2) encontradas foram de 12,3, 9,0, 5,0 e 8,5 para BVDV, BoHV-1, BRSV e BPIV-3. Dos 14 aos 240d os 5 bezerros avaliados, demonstraram declínio gradual dos títulos de Acs (Log2) para BVDV (12,8-3,3), BoHV-1 (10,0-3,3) e BPIV-3 (10,0-2,0), embora o BVDV não tenha apresentado soronegatividade até os 240d. Manifestações clínicas de broncopneumonia foram observadas em 4/5 (80%) bezerros dos 80 aos 135 d. BRSV (11,3-2,0) apresentou perfil diferenciado na dinâmica de anticorpos em relação às demais viroses. Não foram detectadas diferenças estatísticas entre os momentos para as viroses apesar das variações detectadas (P>0,05). A meia-vida e tempo para soronegatividade foram de 36,2±6,1 e 367,01±68,7d para BVDV, 50,7±18,0 e 239,67±66,88d para BoHV-1 e, 46,8±21,1 e 303,36±60,15d para BPIV-3. BRSV não respeitou modelo de regressão para cálculos de meia-vida e soronegatividade. Valores absolutos e relativos das populações de linfócitos não revelaram diferenças estatísticas entre os momentos (P>0,05). Contudo, a dinâmica das subpopulações de linfócitos revelou aumento de células B CD21+ até 150d; aumento nos valores relativos das subpopulações CD4+, CD8+ e CD3+CD4-CD8- principalmente aos 74-90d. Assim, pôde-se determinar uma janela de susceptibilidade a partir dos 74d especialmente ao BRSV e BoHV-1, momento que precede o aumento dos títulos de Acs após exposição natural. Capítulo 2 Objetivou-se avaliar a influência dos Acs maternos na resposta imune para DRB induzida pela vacinação. Foram selecionados 23 bezerros recém-nascidos, distribuídos aleatoriamente entre 4 grupos experimentais: G1 vacinado aos 14d e booster aos 44d; G2 aos 90d e aos 120d; G3 aos 180d e aos 210d. Além disso manteve-se um grupo controle não vacinado CG1, CG2 e CG3. Os bezerros foram vacinados com a mesma vacina comercial empregada para vacinação das doadoras de colostro. Observou-se: (1) a vacina com BVDV inativado não promoveu aumento dos títulos de Acs para nenhum dos grupos avaliados; (2) G1 não demonstrou soroconversão para nenhuma das viroses, enquanto controle CG1 exibiu decréscimo dos títulos para BVDV, BoHV-1 e BPIV-3; (3) o BRSV apresentou baixa soroconversão no G2, enquanto o controle demonstrou altos títulos dos 44-120d; (4) não foi possível distinguir entre quais tempos ocorreram diferenças entre títulos (P>0,0167); (5) linfócitos B (CD21+) aumentaram do T0-T2 para G1, diminuíram para G2, e aumentaram no G3; (6) linfócitos T CD3+ diminuíram ao longo do tempo para todos os grupos, exceto CG3; (7) apesar de oscilações, linfócitos T CD4+, CD8+ e WC1+ se mantiveram praticamente constantes até 240d, exibindo maiores proporções nos grupos vacinados; (8) a expressão do marcador CD25+ foi mantida pelo grupo G1 até o T2, mas apresentou aumento no G2 e G3; (9) manifestações de broncopneumonias foram identificadas nos bezerros do grupo controle (4/5 - 80%) e podem ter exercido influência nas diferenças encontradas para as células entre os grupos. Em geral, a vacinação dos bezerros aos 90 (G2) e 180d (G3) manteve ou estimulou a produção de Acs para o BoHV-1, BRSV e BPIV-3, e a ativação das células T expressas pelo marcador CD25+ pode ter sido responsável pela proteção dos bezerros frente à DRB. Assim, com base nos resultados, concluiu-se que a intensidade da imunidade dos bezerros induzida pela vacinação aumentou de acordo com o desenvolvimento etário e diminuição dos títulos de Acs maternos.
The main purpose of this research was to evaluate the transfer of passive immunity and its influence on vaccine response to the viruses involved in bovine respiratory disease (BRD). The data obtained in this study are presented in two chapters. Chapter 1 - The objective was to evaluate the dynamics of specific antibodies to the respiratory viruses and lymphocyte subpopulations in the calves from birth to 240 days (d) of life. Thus, the transfer of passive immunity of specific antibodies to the respiratory viruses were assessed in 19 calves; from these, five were selected for monitoring the dynamic of neutralizing Abs and lymphocytes subpopulations from 14 to 240d. The colostrum was provided from donor vaccinated cows. The analysis of individual quality of the colostrum revealed Brix 21%, observing strong correlation of these values with total protein (r = 0.942 and P = 0.001). After 48 hours of colostrum intake, was observed seroconversion of the 19 animals (100%) for the viral agents involved in the DBR. The median (Log2) ratio found was 12.3, 9.0, 5.0 and 8.5 for BVDV, BoHV-1, BRSV and BPIV-3. The 5 calves followed from 14 to 240d showed gradual decline in antibody titers (Log2) to BVDV (12.8 to 3.3), BoHV-1 (10.0 to 3.3) and BPIV-3 (10, 0-2.0), although could not be detected seronegative calves for BVDV up to eight months of age. Clinical manifestations of bronchopneumonia were observed in 4/5 (80%) calves from 80 to 135 days of life. BRSV (11.3 to 2.0) showed a distinct profile in the dynamics of antibodies compared to other viruses. There were no statistical differences between times for viruses despite variations detected (P> 0.05). The half-life and time to become seronegative were 36.2±6.1 and 367.01±68.7d for BVDV, 50.7±18.0 and 239.67±66.88d for BoHV-1 and, 46.8±21.1 and 303.36±60.15d for BPIV-3. BRSV did not respect regression model to perform half-life and seronegative calculations. Absolute and relative values of lymphocyte populations revealed no statistical differences between times (P> 0.05). However, the dynamics of lymphocyte subpopulations showed increase in B cells CD21+ up to 150d; increase in the relative values of CD4+, CD8+ and CD3+CD4-CD8- subpopulations, mainly to 74-90d. Thus, it was possible to determine a window of susceptibility since 74d especially for BRSV and BoHV-1, moment that precede the increase in antibody titers after natural exposure. Chapter 2 - The objective was to evaluate the influence of maternal antibodies in the immune response to respiratory viruses induced by vaccination. Was selected 23 newborn calves that were randomly distributed in four groups: G1 - vaccinated at 14d and booster at 44d; G2 - vaccinated at 90d and booster at 120d; G3 - vaccinated at 180d and booster at 210d. Furthermore were kept a non-vaccinated control group - CG1, CG2 and CG3. Calves were vaccinated with the same commercial vaccine in the colostrum donors. From these, could be observed: (1) the vaccine with inactivated BVDV did not promote increase of antibodies titers in any of the assessed groups; (2) G1 did not demonstrated seroconversion for any of the viruses while CG1 control exhibited decrease in the titers for BVDV, BoHV-1 and BPIV-3; (3) BRSV had low seroconversion in G2, while the control showed high titers from 44 to 120d; (4) where the differences between times occurred could not be distinguished (P <0.0167); (5) B cells (CD21+) increased from T0 to T2 for G1, decreased for G2, and increased for G3; (6) T lymphocytes CD3+ decreased over time for all groups except for CG3; (7) despite variations, T lymphocytes CD4+, CD8+ and WC1+ remained almost constant until 240d, displaying greater proportions in the vaccinated groups; (8) the expression of the CD25+ marker was maintained in the vaccinated group G1 up to T2, whereas vaccination promoted an increase of this expression in G2 and G3; (9) clinical manifestations of bronchopneumonia were identified in the control group (4/5 calves - 80%) and may have influence on the differences found for the cells between the groups. In general, vaccination of calves at 90 (G2) and 180d (G3) maintained or stimulated the production of Abs to BoHV-1, BRSV and BPIV-3, and the activation of T cells expressed by the CD25+ marker may have been responsible for the protection of calves from BRD. Thus, based on the results, it was concluded that the intensity of the immunity induced by vaccination of calves increased according to the age of development and decay of maternal antibody titers
Resumo
The RT-PCR technique has been frequentely used for detection of the human parainfluenza virus type 3 (hPIV-3) but the literature is scarce in relation to the bovine parainfluenza virus type 3 (bPIV-3). The aim of this study was to describe a reverse transcriptase polymerase chain reaction (RT-PCR) for detection of bovine parainfluenza virus type 3 (bPIV-3) using degenerate oligonucleotides targeting a conserved region of hemagglutinin-neuraminidase (HN) gene. Reference strain SF-4 and three different brazilian bPIV-3 isolates, besides five viral strains from different sources, were included in this study. Viruses were cultured in MDBK cells under standard conditions. Hemagglutination (HA) test was used for viral titration and a direct immunofluorescence test (DFAT) for isolate screening. In RT-PCR all bPIV-3 isolates showed amplification of an expected 1009 bp fragment of HN gene, as oposed to non PIV-3 viral samples where no amplification was detected. Using SF-4 as positive control, sensitivity of 95 pg cDNA wasachieved. In spite of the low number of bPIV-3 isolates tested, the results obtained in this study point out the potential use of this technique for detection of bPIV-3 in bovine clinical specimens.
Resumo
The RT-PCR technique has been frequentely used for detection of the human parainfluenza virus type 3 (hPIV-3) but the literature is scarce in relation to the bovine parainfluenza virus type 3 (bPIV-3). The aim of this study was to describe a reverse transcriptase polymerase chain reaction (RT-PCR) for detection of bovine parainfluenza virus type 3 (bPIV-3) using degenerate oligonucleotides targeting a conserved region of hemagglutinin-neuraminidase (HN) gene. Reference strain SF-4 and three different brazilian bPIV-3 isolates, besides five viral strains from different sources, were included in this study. Viruses were cultured in MDBK cells under standard conditions. Hemagglutination (HA) test was used for viral titration and a direct immunofluorescence test (DFAT) for isolate screening. In RT-PCR all bPIV-3 isolates showed amplification of an expected 1009 bp fragment of HN gene, as oposed to non PIV-3 viral samples where no amplification was detected. Using SF-4 as positive control, sensitivity of 95 pg cDNA wasachieved. In spite of the low number of bPIV-3 isolates tested, the results obtained in this study point out the potential use of this technique for detection of bPIV-3 in bovine clinical specimens.
Resumo
The RT-PCR technique has been frequentely used for detection of the human parainfluenza virus type 3 (hPIV-3) but the literature is scarce in relation to the bovine parainfluenza virus type 3 (bPIV-3). The aim of this study was to describe a reverse transcriptase polymerase chain reaction (RT-PCR) for detection of bovine parainfluenza virus type 3 (bPIV-3) using degenerate oligonucleotides targeting a conserved region of hemagglutinin-neuraminidase (HN) gene. Reference strain SF-4 and three different brazilian bPIV-3 isolates, besides five viral strains from different sources, were included in this study. Viruses were cultured in MDBK cells under standard conditions. Hemagglutination (HA) test was used for viral titration and a direct immunofluorescence test (DFAT) for isolate screening. In RT-PCR all bPIV-3 isolates showed amplification of an expected 1009 bp fragment of HN gene, as oposed to non PIV-3 viral samples where no amplification was detected. Using SF-4 as positive control, sensitivity of 95 pg cDNA wasachieved. In spite of the low number of bPIV-3 isolates tested, the results obtained in this study point out the potential use of this technique for detection of bPIV-3 in bovine clinical specimens.
Resumo
The RT-PCR technique has been frequentely used for detection of the human parainfluenza virus type 3 (hPIV-3) but the literature is scarce in relation to the bovine parainfluenza virus type 3 (bPIV-3). The aim of this study was to describe a reverse transcriptase polymerase chain reaction (RT-PCR) for detection of bovine parainfluenza virus type 3 (bPIV-3) using degenerate oligonucleotides targeting a conserved region of hemagglutinin-neuraminidase (HN) gene. Reference strain SF-4 and three different brazilian bPIV-3 isolates, besides five viral strains from different sources, were included in this study. Viruses were cultured in MDBK cells under standard conditions. Hemagglutination (HA) test was used for viral titration and a direct immunofluorescence test (DFAT) for isolate screening. In RT-PCR all bPIV-3 isolates showed amplification of an expected 1009 bp fragment of HN gene, as oposed to non PIV-3 viral samples where no amplification was detected. Using SF-4 as positive control, sensitivity of 95 pg cDNA wasachieved. In spite of the low number of bPIV-3 isolates tested, the results obtained in this study point out the potential use of this technique for detection of bPIV-3 in bovine clinical specimens.
Resumo
The RT-PCR technique has been frequentely used for detection of the human parainfluenza virus type 3 (hPIV-3) but the literature is scarce in relation to the bovine parainfluenza virus type 3 (bPIV-3). The aim of this study was to describe a reverse transcriptase polymerase chain reaction (RT-PCR) for detection of bovine parainfluenza virus type 3 (bPIV-3) using degenerate oligonucleotides targeting a conserved region of hemagglutinin-neuraminidase (HN) gene. Reference strain SF-4 and three different brazilian bPIV-3 isolates, besides five viral strains from different sources, were included in this study. Viruses were cultured in MDBK cells under standard conditions. Hemagglutination (HA) test was used for viral titration and a direct immunofluorescence test (DFAT) for isolate screening. In RT-PCR all bPIV-3 isolates showed amplification of an expected 1009 bp fragment of HN gene, as oposed to non PIV-3 viral samples where no amplification was detected. Using SF-4 as positive control, sensitivity of 95 pg cDNA wasachieved. In spite of the low number of bPIV-3 isolates tested, the results obtained in this study point out the potential use of this technique for detection of bPIV-3 in bovine clinical specimens.
Resumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detect
Resumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detect
Resumo
Background: Respiratory tract diseases are commonly seen in beef cattle. Young calves are affected with many respiratory pathogens. Viral pathogens are particularly seen. There are many causative factors, e.g. environmental conditions, immune system of calves. Therefore, alternative treatments are needed for viral respiratory infections. The purpose of the current study was to investigate effectiveness of Umckaloabo/EPs®7630 liquid extract in some bovine viral pathogens of young beef calves.Materials, Methods & Results: Antibody presence in terms of bovine herpesvirus type 1 (BHV-1), bovine viral diarrhea virus (BVDV), bovine parainfluenza virus type 3 (BPIV-3), bovine respiratory syncytial virus (BRSV) and bovine adenovirus type 3 (BAV-3) was searched in blood serum samples of 40 Holstein calves aged 6 months and over showing respiratory tract infection symptoms. All animals were found seronegative in terms of other factors except BRSV. Out of 20 BRSV seropositive calves, 10 of them were classified as control group and the other ten as testing group. BRSV antibody titers were also detected in blood samples of both groups on day 0. Umckaloabo/EPs®7630 liquid extract was given through oral route to animals in testing group according to their weights for 14 days morning, noon and night. No application was performed on animals in control group. BRSV antibody titers were detect