Efficacy of prepartum vaccination against neonatal calf diarrhea in Nelore dams as a prevention measure

Background: Neonatal calf diarrhea (NCD) is the leading cause of calf morbidity and mortality in beef cattle. Cow’s vaccination in last stage of pregnancy is one of the most important measures to mitigate the risk of NCD outbreaks. The aim of this study was to evaluate the efficacy of prepartum single dose vaccination against NCD, especially Bovine Rotavirus type A (BoRVA) and Bovine Coronavirus (BCoV), in Nelore dams and offspring. A total of 117 pregnant cows (n = 81) and heifers (n = 36) were distributed in two groups, vaccinated (VAC: cows = 40; heifers = 19) and nonvaccinated (NVAC: cows = 41; heifers = 17). Vaccination occurred between 60 to 50 days before the expected calving date with a single dose of a water-in-oil (W/O) vaccine, and NVAC group received a dose of saline solution 0.9%. Blood samples were collected before vaccination and 30 days after to evaluate the antibody (Ab) response. Specific IgG1 Abs against BoRVA and BCoV were measured by using an Enzyme Linked Immuno Sorbent Assay (ELISA). Calves’ births were monitored, and the transference of passive immunity was evaluated. Diarrhea was monitored in the first 30 days of age, and fecal samples were collected for identification of the etiological agent. Results: Higher titers of IgG1 Ab against BoRVA and BCoV was observed in the VAC group than NVAC group in the cow (P < 0.0001) and total dams categories (P < 0.0001). The titer of specific IgG1 Abs in the calves’ serum reflected the dams response, observing higher IgG1 Ab titers for BoRVA (P < 0.0016) and BCoV (P < 0.0095) in the offspring born to VAC cows and higher IgG1 Ab titers for BoRVA(P < 0.0171) and BCoV (P < 0.0200) in the offspring born to VAC total dams. The general incidence of diarrhea observed was 18.6% (11/59) and 29.3% (17/58) in the calves born to the VAC and NVAC group, respectively. Conclusions: Prepartum vaccination with a single dose of the vaccine tested increased the titers of IgG1 Ab against BCoV and BoRVA, and it could be used as a preventive strategy to decrease the NCD occurrence in Nelore calves.Instituto de VirologíaFil: Pinheiro, Filipe Aguera. University of São Paulo. College of Veterinary Medicine and Animal Science. Department of Internal Medicine; BrasilFil: Decaris, Nathália. University of São Paulo. College of Veterinary Medicine and Animal Science. Department of Internal Medicine; BrasilFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria (INTA). INCUINTA. Instituto de Virologia e Innovaciones Tecnologicas; ArgentinaFil: Parreño, Gladys Viviana. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Brandão, Paulo Eduardo. University of São Paulo. College of Veterinary Medicine and Animal Science. Department of Preventive Veterinary Medicine and Animal Health of Internal Medicine; BrasilFil: Ayres, Henderson. MSD Animal Health; BrasilFil: Gomes, Viviani. University of São Paulo. College of Veterinary Medicine and Animal Science. Department of Internal Medicine; Brasi

Prepartum vaccination of Nelore cows against neonatal diarrhea

A diarreia neonatal dos bezerros (DNB) é um dos eventos de saúde mais importantes durante o período de criação de bezerros de corte, sendo responsável por grande parte da morbidade e mortalidade nesta fase. Entre as medidas para mitigar o risco de surtos de DNB, a vacinação da vaca na última fase da gestação é uma das mais importantes. O objetivo desta pesquisa foi avaliar a eficácia da vacinação pré-parto contra DNB, especialmente Rotavírus Bovino tipo A (BoRVA) e Coronavírus Bovino (BCoV), em animais da raça Nelore. Um total de 117 animais, divididos em vacas (n=81) e novilhas (n=36) foram distribuídos em dois grupos experimentais, sendo estes: grupo de animais vacinados (VAC: vacas=40; novilhas=19) e grupo de animais não vacinados (NVAC: vacas=41; novilhas=17). O tratamento dos animais ocorreu entre 60 a 50 dias antes da data prevista para o parto, sendo aplicado no grupo VAC uma única dose de uma vacina comercial (2mL), administrado por via intramuscular, e no grupo NVAC uma dose de solução salina 0,9%. Amostras de sangue foram coletadas imediatamente antes da vacinação e após 30 dias, para avaliar a resposta de anticorpos específicos (IgG1) contra BoRVA e BCoV. O nascimento dos bezerros foi monitorado e a transferência de imunidade passiva foi avaliada entre o segundo e o terceiro dias de vida. A diarreia foi monitorada nos primeiros 30 dias de idade, e amostras de fezes foram coletadas para identificação do agente etiológico em animais com diarreia. Como controle, amostras de fezes de bezerros saudáveis com idade semelhante à dos animais com diarreia, também foram coletadas. Os anticorpos específicos (IgG1) contra BoRVA e BCoV foram medidos usando a técnica Enzyme Linked Immuno Sorbent Assay (ELISA). A comparação de médias pelo teste T de Student mostrou títulos mais elevados de IgG1 contra BoRVA e BCoV no grupo VAC quando comparado ao grupo NVAC na categoria de vacas (P &#60; 0,0001) e no total de animais (P &#60; 0,0001). Em relação aos bezerros, não houve diferenças (P &#62;0,05) entre os grupos para a concentração de proteína total sérica (PTS) e taxa (%) de falha da transferência imune passiva (FTIP). O título de IgG1 específico no soro de bezerros refletiu a resposta das mães, observando títulos mais elevados de IgG1 para BoRVA (P &#60; 0,0016) e BCoV (P &#60;0,0095) nos bezerros nascidos da categoria de vacas do grupo VAC; e títulos mais elevados de IgG1 para BoRVA (P &#60; 0,0171) e BCoV (P &#60; 0,0200) nos bezerros nascidos do total de animais do grupo VAC. A incidência geral de diarreia observada foi de 18,6% (11/59) e 29,3% (17/58) nos bezerros nascidos do grupo VAC e NVAC, respectivamente. Apesar da diferença observada, o pequeno tamanho amostral não permitiu detectar diferenças estatísticas entre os grupos experimentais para diarreia (P &#62;0,05). Entre bezerros com diarreia, o agente mais prevalente foi o BoRVA. A vacinação pré-parto com uma única dose da vacina testada aumentou os títulos de IgG1 contra BCoV e BoRVA, podendo ser utilizada como estratégia preventiva para diminuir a ocorrência de DNB em animais da raça Nelore.Neonatal calf diarrhea (NCD) is one of the most important health events during the rearing period of beef calves, accounting for much of the morbidity and mortality at this stage. Among the measures to mitigate the risk of NCD outbreaks, cow vaccination in the last stage of pregnancy is one of the most important. The objective of this research was to evaluate the effectiveness of prepartum vaccination against NCD, especially Bovine Rotavirus type A (BoRVA) and Bovine Coronavirus (BCoV), in Nelore animals. A total of 117 animals, divided into cows (n=81) and heifers (n=36) were divided into two experimental groups, namely: vaccinated animal group (VAC: cows=40; heifers=19) and animal group unvaccinated (NVAC: cows=41; heifers=17). The treatment of the animals occurred between 60 to 50 days before the expected date of calving, with a single dose of a commercial vaccine (2mL) being applied to the VAC group, administered intramuscularly, and to the NVAC group a dose of saline solution 0, 9%. Blood samples were collected immediately before vaccination and after 30 days to assess the specific antibody response (IgG1) against BoRVA and BCoV. The calf birth was monitored and the transfer of passive immunity was evaluated between the second and third days of life. Diarrhea was monitored in the first 30 days of age, and stool samples were collected to identify the etiologic agent in animals with diarrhea. As a control, fecal samples from healthy calves with age similar to that of animals with diarrhea were also collected. Specific antibodies (IgG1) against BoRVA and BCoV were measured using the Enzyme Linked Immuno Sorbent Assay (ELISA) technique. Comparison of means by Student &#8242;s t test showed higher IgG1 titers against BoRVA and BCoV in the VAC group when compared to the NVAC group in the cows category (P &#60;0.0001) and in total animals (P &#60;0.0001) . In relation to calves, there were no differences (P &#62;0.05) between groups for serum total protein concentration (STP) and rate (%) of passive immune transfer failure (PITF). The specific IgG1 titer in the serum of calves reflected the response of the dams, observing higher IgG1 titers for BoRVA (P &#60;0.0016) and BCoV (P &#60;0.0095) in calves born from the category of cows in the VAC group; and higher IgG1 titers for BoRVA (P &#60;0.0171) and BCoV (P &#60;0.0200) in calves born from the total number of animals in the VAC group. The overall incidence of diarrhea observed was 18.6% (11/59) and 29.3% (17/58) in calves born in the VAC and NVAC groups, respectively. Despite the observed difference, the small sample size did not allow detecting statistical differences between the experimental groups for diarrhea (P &#62;0.05). Among calves with diarrhea, the most prevalent agent was BoRVA. Prepartum vaccination with a single dose of the tested vaccine increased IgG1 titers against BCoV and BoRVA, and can be used as a preventive strategy to reduce the occurrence of NCD in Nelore animals

Efficacy of prepartum vaccination against neonatal calf diarrhea in Nelore dams as a prevention measure

Background: Neonatal calf diarrhea (NCD) is the leading cause of calf morbidity and mortality in beef cattle. Cow’s vaccination in last stage of pregnancy is one of the most important measures to mitigate the risk of NCD outbreaks. The aim of this study was to evaluate the efficacy of prepartum single dose vaccination against NCD, especially Bovine Rotavirus type A (BoRVA) and Bovine Coronavirus (BCoV), in Nelore dams and offspring. A total of 117 pregnant cows (n = 81) and heifers (n = 36) were distributed in two groups, vaccinated (VAC: cows = 40; heifers = 19) and non-vaccinated (NVAC: cows = 41; heifers = 17). Vaccination occurred between 60 to 50 days before the expected calving date with a single dose of a water-in-oil (W/O) vaccine, and NVAC group received a dose of saline solution 0.9%. Blood samples were collected before vaccination and 30 days after to evaluate the antibody (Ab) response. Specific IgG1 Abs against BoRVA and BCoV were measured by using an Enzyme Linked Immuno Sorbent Assay (ELISA). Calves’ births were monitored, and the transference of passive immunity was evaluated. Diarrhea was monitored in the first 30 days of age, and fecal samples were collected for identification of the etiological agent. Results: Higher titers of IgG1 Ab against BoRVA and BCoV was observed in the VAC group than NVAC group in the cow (P < 0.0001) and total dams categories (P < 0.0001). The titer of specific IgG1 Abs in the calves’ serum reflected the dams response, observing higher IgG1 Ab titers for BoRVA (P < 0.0016) and BCoV (P < 0.0095) in the offspring born to VAC cows and higher IgG1 Ab titers for BoRVA(P < 0.0171) and BCoV (P < 0.0200) in the offspring born to VAC total dams. The general incidence of diarrhea observed was 18.6% (11/59) and 29.3% (17/58) in the calves born to the VAC and NVAC group, respectively. Conclusions: Prepartum vaccination with a single dose of the vaccine tested increased the titers of IgG1 Ab against BCoV and BoRVA, and it could be used as a preventive strategy to decrease the NCD occurrence in Nelore calves.Fil: Aguera Pinheiro, Filipe. Universidade de Sao Paulo; BrasilFil: Decaris, Nathália. Universidade de Sao Paulo; BrasilFil: Parreño, Gladys Viviana. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología e Innovaciones Tecnológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Virología e Innovaciones Tecnológicas; ArgentinaFil: Brandão, Paulo Eduardo. Universidade de Sao Paulo; BrasilFil: Ayres, Henderson. No especifíca;Fil: Gomes, Viviani. Universidade de Sao Paulo; Brasi

<i>Cryptosporidium</i> spp. and <i>Giardia</i> spp. in feces and water and the associated exposure factors on dairy farms

<div><p>The aims of this study were to verify the prevalence of <i>Cryptosporidium</i> spp. and <i>Giardia</i> spp. in animal feces and drinking water on dairy farms and to identify a possible relation between the exposure factors and the presence of these parasites. Fecal samples from cattle and humans and water samples were collected on dairy farms in Paraná, Brazil. Analysis of (oo)cysts in the feces was performed by the modified Ziehl-Neelsen staining and centrifugal flotation in zinc sulfate. Test-positive samples were subjected to nested PCR amplification of <i>the 18SSU</i> ribosomal RNA gene for identification of <i>Cryptosporidium</i> and <i>Giardia</i> and of the <i>gp60</i> gene for subtyping of <i>Cryptosporidium</i>. Microbiological analysis of water was carried out by the multiple-tube method and by means of a chromogenic substrate, and parasitological analysis was performed on 31 samples by direct immunofluorescence and nested PCR of the genes mentioned above. Identification of the species of <i>Cryptosporidium</i> was performed by sequencing and PCR with analysis of restriction fragment length polymorphisms. The prevalence of <i>Giardia</i> and <i>Cryptosporidium</i> was higher in calves than in adults. Among the samples of cattle feces, <i>Cryptosporidium parvum</i> was identified in 41 (64%), <i>C</i>. <i>ryanae</i> in eight (12.5%), <i>C</i>. <i>bovis</i> in four (6.3%), <i>C</i>. <i>andersoni</i> in five (7.8%), and a mixed infection in 20 samples (31.3%). These parasites were not identified in the samples of human feces. Thermotolerant coliform bacteria were identified in 25 samples of water (45.5%). <i>Giardia duodenalis</i> and <i>C</i>. <i>parvum</i> were identified in three water samples. The <i>gp60</i> gene analysis of <i>C</i>. <i>parvum</i> isolates revealed the presence of two strains (IIaA20G1R1 and IIaA17G2R2) in the fecal samples and one (IIaA17G2R1) in the water samples. The presence of coliforms was associated with the water source, structure and degradation of springs, rain, and turbidity. The prevalence of protozoa was higher in calves up to six months of age. <i>C</i>. <i>parvum</i> and <i>G</i>. <i>duodenalis</i> were identified in the water of dairy farms, as were thermotolerant coliforms; these findings point to the need for guidance on handling of animals, preservation of water sources, and water treatment.</p></div

Variables with a statistically significant association with the presence of cysts of <i>Giardia</i> spp. and/or oocysts of <i>Cryptosporidium</i> spp. in fecal samples from 937 heads of dairy cattle in Paraná, Brazil, from 2012 to 2014.

<p>Variables with a statistically significant association with the presence of cysts of <i>Giardia</i> spp. and/or oocysts of <i>Cryptosporidium</i> spp. in fecal samples from 937 heads of dairy cattle in Paraná, Brazil, from 2012 to 2014.</p

Springhead, turbidity, bacteriological parameters of water samples positive for <i>Cryptosporidium</i> or <i>Giardia</i> species identified by genetic sequencing, and rainfall data 24 and 48 h prior to collection on four dairy farms in Paraná, Brazil, in 2014.

<p>Springhead, turbidity, bacteriological parameters of water samples positive for <i>Cryptosporidium</i> or <i>Giardia</i> species identified by genetic sequencing, and rainfall data 24 and 48 h prior to collection on four dairy farms in Paraná, Brazil, in 2014.</p

Prevalence of <i>Giardia</i> spp and <i>Cryptosporidium</i> spp in feces of cattle from 55 dairy farms in Paraná, Brazil, from 2012 to 2014.

<p>Prevalence of <i>Giardia</i> spp and <i>Cryptosporidium</i> spp in feces of cattle from 55 dairy farms in Paraná, Brazil, from 2012 to 2014.</p

Variables with a statistically significant association with the presence of thermotolerant coliforms in 124 water samples from 55 dairy farms in Paraná, Brazil, from 2012 to 2014.

<p>Variables with a statistically significant association with the presence of thermotolerant coliforms in 124 water samples from 55 dairy farms in Paraná, Brazil, from 2012 to 2014.</p

A flowchart of retrieval and analysis of fecal and water samples from 55 dairy farms in Paraná, Brazil, during 2012–2014.

<p>A flowchart of retrieval and analysis of fecal and water samples from 55 dairy farms in Paraná, Brazil, during 2012–2014.</p