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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Avaliação colostral e de níveis séricos imunes de bezerros holandezes oriundos de vacas acometidas ou não por mastite

Santos, Guilherme Gonçalves Fabretti [UNESP] 01 April 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:23:09Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-04-01Bitstream added on 2014-06-13T19:49:39Z : No. of bitstreams: 1 000721465.pdf: 1538253 bytes, checksum: 19e309686a5c02fbf745f13b76123818 (MD5) / The aim of this study was to evaluate the transfer of passive immunity (TPI) in Holstein calves delivery from cows with subclinical and clinical mastitis. Four groups of studies were evaluated. Group I (GI) 10 healthy primiparous cows with SCC ≤ 300,000 cells/mL, Group II (GII) 10 healthy multiparous cows with SCC 301-600,000 cells/mL, Group III (GIII) 10 multiparous cows with mastitis records that calved with subclinical mastitis with SCC> 600,000 cells/mL with normality in udder and colostrum and Group IV (GIV) 10 multiparous cows with mastitis records that calved with clinical mastitis with SCC> 600 000 cells/mL with changes in the udder and/or colostrum. Blood samples and colostrum were collected immediately after birth, 24 and 48 hours after delivery/birth. The microbiological culture showed that Streptococcus sp. and Staphylococcus sp. were the most common bacteria isolated from cows with subclinical and clinical mastitis respectively. The SCC stipulated for the control group cannot be followed, since the secretions of healthy animals showed average values greater than 992,000 cells/mL of colostrum. CMT can be useful to confirm mastitis in post-partum period. The ultrasound was effective in determining parenchyma affected by infection. No differences were observed between the values of the protein constituents of colostrum and values of cytokines in multiparous and primiparous cows. Ingestion of colostrum derived from cows with clinical and subclinical mastitis is unlikely to be an important contributor to failure of passive transfer in calves
2

Avaliação colostral e de níveis séricos imunes de bezerros holandezes oriundos de vacas acometidas ou não por mastite /

Santos, Guilherme Gonçalves Fabretti. January 2013 (has links)
Resumo:O objetivo do estudo foi avaliar a transferência de imunidade passiva (TIP) de vacas que pariram com mastite assintomática e clínica para os seus bezerros. Foram avaliados quatro grupos, a saber: Grupo I (GI) composto de 10 vacas primíparas sadias com contagem de células somáticas (CCS) ≤300 mil cél/mL, Grupo II (GII) composto de 10 vacas pluríparas sadias com CCS 301-600 mil cél/mL; Grupo III (GIII) composto de 10 vacas pluríparas com histórico de mastite que pariram com mastite assintomática com CCS>600 mil cél/mL sem alterações no úbere e colostro; e Grupo IV (GIV) composto por 10 vacas pluríparas com histórico de mastite que pariram com mastite clínica com CCS>600 mil cél/mL com alterações no úbere e/ou colostro. Foram coletadas amostras de sangue e colostro imediatamente após o parto, 24 e 48 horas após o parto/nascimento. O cultivo microbiológico mostrou ser Streptococcus sp. o principal agente isolado nos animais com mastite assintomática e o Staphylococcus sp. nos animais com mastite clínica. A CCS estipulada para os animais do grupo controle não pode ser seguida, uma vez que as secreções de animais sadios apresentaram valores médios superiores a 992 mil cél/mL de colostro. O CMT foi valioso no diagnóstico a mastite no pós-parto imediato. O exame ultrassonográfico mostrou-se eficaz na determinação de parênquimas acometidos por infecção. Não foram observadas diferenças entre os valores dos constituintes proteicos do colostro e dos valores de citocinas de vacas primíparas e pluríparas. A ingestão de colostro oriundo de vacas com mastite clínica e assintomática não causa falha na transferência de imunidade passiva nos respectivos conceptos / Abstract:The aim of this study was to evaluate the transfer of passive immunity (TPI) in Holstein calves delivery from cows with subclinical and clinical mastitis. Four groups of studies were evaluated. Group I (GI) 10 healthy primiparous cows with SCC ≤ 300,000 cells/mL, Group II (GII) 10 healthy multiparous cows with SCC 301-600,000 cells/mL, Group III (GIII) 10 multiparous cows with mastitis records that calved with subclinical mastitis with SCC> 600,000 cells/mL with normality in udder and colostrum and Group IV (GIV) 10 multiparous cows with mastitis records that calved with clinical mastitis with SCC> 600 000 cells/mL with changes in the udder and/or colostrum. Blood samples and colostrum were collected immediately after birth, 24 and 48 hours after delivery/birth. The microbiological culture showed that Streptococcus sp. and Staphylococcus sp. were the most common bacteria isolated from cows with subclinical and clinical mastitis respectively. The SCC stipulated for the control group cannot be followed, since the secretions of healthy animals showed average values greater than 992,000 cells/mL of colostrum. CMT can be useful to confirm mastitis in post-partum period. The ultrasound was effective in determining parenchyma affected by infection. No differences were observed between the values of the protein constituents of colostrum and values of cytokines in multiparous and primiparous cows. Ingestion of colostrum derived from cows with clinical and subclinical mastitis is unlikely to be an important contributor to failure of passive transfer in calves / Orientador:Francisco Leydson Formiga Feitosa / Banca:Marcia Marinho / Banca:Alice Maria Ville Paiva Della Libera / Mestre
3

Interpretation of the Detection of Antibodies to Sarcocystis neurona in the serum and CSF of young horses

Cook, Anne Grimsley 02 July 2001 (has links)
Horses that are exposed to Sarcocystis neurona, a causative agent of equine protozoal myeloencephalitis, produce antibodies that are detectable in serum by western blot (WB). A positive test is indicative of exposure to the organism. Positive tests in young horses can be complicated by the presence of maternal antibodies. Passive transfer of maternal antibodies to S. neurona from seropositive mares to their foals was evaluated. Foals were sampled at birth (presuckle), at 24 hours of age (postsuckle), and at monthly intervals. All foals sampled before suckling were seronegative. Thirty-three foals from 33 seropositive mares became seropositive with colostrum ingestion at 24 hours of age, confirming that passive transfer of S. neurona maternal antibodies occurs. Thirty-one of the 33 foals became seronegative by 9 months of age, with a mean seronegative conversion time of 4.2 months. These results indicate that evaluation of exposure to S. neurona by WB analysis of serum may be misleading in young horses. Cerebrospinal fluid (CSF) samples from 15 neonatal (2-8 day) foals were examined for the presence of antibodies to S. neurona by WB analysis. Twelve of 13 foals that were seropositive were also CSF positive, suggesting that maternal antibodies to S. neurona cross the blood-CSF barrier in neonatal foals resulting in a positive CSF WB. Repeat taps were performed on 5 of the foals which showed that the immunoreactivity of the western blot decreases over time. Two of the 5 foals were CSF negative at 83 and 84 days of age, with 1 foal still positive at 90 days, and 2 foals positive at 62 days. These results indicate that maternal antibodies to S. neurona in the CSF can confound WB results in neonatal foals up to several months of age. / Master of Science
4

Survey of colostrum quality and management practices on commercial dairy farms in the Eastern Cape Province of South Africa

Schoombee, Wilhelm Sternberg 06 1900 (has links)
Bovine maternal antibodies are not transferred across the placenta during pregnancy and newborn calves are unable to produce their own antibodies within the first weeks after birth. As neonates are born agammaglobulinemic they need to acquire immunoglobulins (Ig) from their dam’s colostrum to acquire passive immunity. Colostrum fed to dairy calves, which is not timeous, of inadequate quantity and of unverified quality, might result in decreased neonate health. The aim of this study was to conduct a survey of the management of colostrum on commercial dairy farms, to estimate the quality of the Ig titre of colostrum fed to neonates and finally to recommend methods and techniques critical to the successful management of colostrum. The methods used included a questionnaire which was conducted as a structured interview on a one-on-one basis among 50 randomly selected commercial dairy farmers in the Eastern Cape Coastal Region of South Africa. The estimation of the colostrum Ig titre of colostrum fed to neonates was made by the on-farm measurement of specific gravity (SG) by making use of a commercially available KRUUSE colostrometer (Fleenor and Stott, 1980). A pooled colostrum sample, from each of the four quarters, from 90 randomly selected post-partum cows was collected on a leader commercial dairy farm. This method was used to compare colostrum samples from cows run under similar management practices. These samples were collected for analysis within 6 hrs of calving and were done over 3 seasons (autumn, winter and spring). Survey - The colostrum mass and timing of the initial feed are the most important factors when aiming to achieve adequate passive immunity. The results of the survey indicated that most of the farmers of this region feed an inadequate mass of colostrum (volume and Ig concentration) and only 52% of farmers surveyed feed colostrum less than 6 hrs post- partum. The majority (78%) of surveyed farmers did not follow up their initial colostrum feeding.Colostrum sampling - At the trial site only 10% (9 from 90 colostrum samples measured), were found to be of adequate SG quality. Cow age (parity), season of calving and colostrum temperature had an influence on the estimated colostrum SG. However, season of calving was found to have the greatest influence on SG values. These results were consistent with findings from previous studies that SG values from the cooler months were higher than those of the hotter months. Tables 4.7 (P=0.330), 4.8 (P=0.012) and 4.9 (P=0.005) showed that regression analysis confirmed that LS means across seasons were inadequately below the required 50 mg/ml Ig required for sufficient passive immunity. Tables 4.1 (P=0.164), 4.2 (P=0.011) and 4.3 (P=0.021) shows that season of calving had a much greater effect on CR than did parity, Table 4.5 (P=0.177). Table 4.4 shows that colostrum temperature has an significant effect on SG value. Recommendations for methods and techniques critical to the successful management of colostrum were made. These recommendations were based on the analysis of the data obtained from the questionnaire and the on-farm colostrum sampling study. The most important and critical management practices surveyed includes the timing of the cow and calf separation where it was found that only 30 from the 50 (60%) of the farms surveyed separate calves and dams at day (0), 19 from 50 farms (38%) separate at day (3-5) and 1 from 50 farms (2%) separate only at day 7 or later. Thus 40% of surveyed farms allow cows to nurse their calves. With regards to early exposure to pathogens this is a high risk management practice. Further to that, only 2 from 50 surveyed farms (4%) measure the colostrum quality fed to their calves and 48 from 50 farms (96%) feed colostrum of unmeasured quality. The mass of colostrum fed to calves is an important parameter for successful transmission of Ig. In the survey it was found that 28 from 50 farms (56%) feed 2L – 4L of colostrum and 11 from 50 farms (22%) feed 2L of colostrum. Thus 78% of farms feed approximately 50% of the amount of colostrum required for successful transmission of Ig. Finally only 1 from 50 farms (2%) freeze excess colostrum and 1 from 50 farms (2%) pool excess colostrum. Both these farms measure colostrum quality by colostrometer. / Agriculture Animal Health and Human Ecology / M. Sc. (Agriculture)
5

Survey of colostrum quality and management practices on commercial dairy farms in the Eastern Cape Province of South Africa

Schoombee, Wilhelm Sternberg 06 1900 (has links)
Bovine maternal antibodies are not transferred across the placenta during pregnancy and newborn calves are unable to produce their own antibodies within the first weeks after birth. As neonates are born agammaglobulinemic they need to acquire immunoglobulins (Ig) from their dam’s colostrum to acquire passive immunity. Colostrum fed to dairy calves, which is not timeous, of inadequate quantity and of unverified quality, might result in decreased neonate health. The aim of this study was to conduct a survey of the management of colostrum on commercial dairy farms, to estimate the quality of the Ig titre of colostrum fed to neonates and finally to recommend methods and techniques critical to the successful management of colostrum. The methods used included a questionnaire which was conducted as a structured interview on a one-on-one basis among 50 randomly selected commercial dairy farmers in the Eastern Cape Coastal Region of South Africa. The estimation of the colostrum Ig titre of colostrum fed to neonates was made by the on-farm measurement of specific gravity (SG) by making use of a commercially available KRUUSE colostrometer (Fleenor and Stott, 1980). A pooled colostrum sample, from each of the four quarters, from 90 randomly selected post-partum cows was collected on a leader commercial dairy farm. This method was used to compare colostrum samples from cows run under similar management practices. These samples were collected for analysis within 6 hrs of calving and were done over 3 seasons (autumn, winter and spring). Survey - The colostrum mass and timing of the initial feed are the most important factors when aiming to achieve adequate passive immunity. The results of the survey indicated that most of the farmers of this region feed an inadequate mass of colostrum (volume and Ig concentration) and only 52% of farmers surveyed feed colostrum less than 6 hrs post- partum. The majority (78%) of surveyed farmers did not follow up their initial colostrum feeding.Colostrum sampling - At the trial site only 10% (9 from 90 colostrum samples measured), were found to be of adequate SG quality. Cow age (parity), season of calving and colostrum temperature had an influence on the estimated colostrum SG. However, season of calving was found to have the greatest influence on SG values. These results were consistent with findings from previous studies that SG values from the cooler months were higher than those of the hotter months. Tables 4.7 (P=0.330), 4.8 (P=0.012) and 4.9 (P=0.005) showed that regression analysis confirmed that LS means across seasons were inadequately below the required 50 mg/ml Ig required for sufficient passive immunity. Tables 4.1 (P=0.164), 4.2 (P=0.011) and 4.3 (P=0.021) shows that season of calving had a much greater effect on CR than did parity, Table 4.5 (P=0.177). Table 4.4 shows that colostrum temperature has an significant effect on SG value. Recommendations for methods and techniques critical to the successful management of colostrum were made. These recommendations were based on the analysis of the data obtained from the questionnaire and the on-farm colostrum sampling study. The most important and critical management practices surveyed includes the timing of the cow and calf separation where it was found that only 30 from the 50 (60%) of the farms surveyed separate calves and dams at day (0), 19 from 50 farms (38%) separate at day (3-5) and 1 from 50 farms (2%) separate only at day 7 or later. Thus 40% of surveyed farms allow cows to nurse their calves. With regards to early exposure to pathogens this is a high risk management practice. Further to that, only 2 from 50 surveyed farms (4%) measure the colostrum quality fed to their calves and 48 from 50 farms (96%) feed colostrum of unmeasured quality. The mass of colostrum fed to calves is an important parameter for successful transmission of Ig. In the survey it was found that 28 from 50 farms (56%) feed 2L – 4L of colostrum and 11 from 50 farms (22%) feed 2L of colostrum. Thus 78% of farms feed approximately 50% of the amount of colostrum required for successful transmission of Ig. Finally only 1 from 50 farms (2%) freeze excess colostrum and 1 from 50 farms (2%) pool excess colostrum. Both these farms measure colostrum quality by colostrometer. / Agriculture Animal Health and Human Ecology / M. Sc. (Agriculture)

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