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Progesterone levels in fat-eree milk of cows during post partum period and early pregnancy diagnosis | Níveis de progesterona em leite desnatado de vacas no período pós- parto e diagnóstico precoce de gestação
1993
José Lázaro da Rocha | Valquiria Hyppolito Barnabe | Renato Campanarut Barnabe | Ed Hoffman Madureira | Claudio Alvarenga de Oliveira | José Antonio Visintin
<p>Progesterone concentrations were measured by radioimmunoassay in fat-free milk samples obtained weekly from 26 primiparous, suckling cows, raised in range conditions. Samples were collected in post partum period up to observation of first signs of estrus. Profiles of progesterone concentrations for early pregnancy diagnosis were also examined on milk samples taken 21 days after artificial insemination. Results showed ovarian ciclicity starting 9.89 weeks post partum in crossed Gir x Caracu cows, with 0.28 nmol/1 progesterone on the day of estrus anti 7.62 nmol/1 21 days post Al. In crossed Nelore x Caracu cows, these results were 12.08 weeks, 0.46 nmol/1 and 9.23 nmol/1, respectively. Ten pregnancies out of 12 diagnosed were confirmed by rectal palpation. There was one case of embryo mortality and three AI were practiced during luteal phase. Estrus observation efficiency was 52.94%, since out of 34 heats identified through hormonal determinations, 18 were detected visually. Variations between crossings did not significantly alter progesterone profiles on day of estrus, nor on 21<sup>th </sup>day after AI or as for ovarian activity post partum.</p> | <p>Foram avaliados os períodos pós-parto de vacas primíparas mestiças Gir x Caracu e Nelore x Caracu mantidas em regime extensivo de pastagem. Para a determinação dos níveis hormonais de progesterona, amostras de leite foram coletadas semanalmente até que os animais apresentassem o 1º estro perceptível, quando foram inseminadas artificialmente. Decorridos 21 dias da inseminação, amostras foram coletadas e dosadas para fazer o diagnóstico precoce de gestação. Os resultados mostraram início de ciclicidade ovariana com 9,89 semanas após o parto para vacas Gir x Caracu, com valores médios de progesterona de 0,28 nmol/l no dia do estro e 7,62 nmol/1 aos 21 dias após a inseminação. Para vacas Nelore x Caracu, o estro se deu com 12,08 semanas após o parto e com valores médios de progesterona de 0,46 nmol/l e 9.23 nmol/1 para o dia do estro e no 21º dia, respectivamente. Dez gestações de doze diagnosticadas no 21º dia foram confirmadas por palpação retal, tendo ocorrido um caso de mortalidade embrionária precoce. Outras três vacas foram inseminadas durante a fase luteínica. A eficiência na observação de estros foi de 52.94%, pois de 34 identificados pelos níveis hormonais, 18 foram percebidos visualmente. A variação entre os cruzamentos não alterou significativamente o nível de progesterona no dia do estro, tampouco no 21º dia após inseminação e também quanto ao período necessário ao reinício da atividade ovariana pós - parto.</p>
Mostrar más [+] Menos [-]Molecular Analysis of Rabies-Related Viruses from Ethiopia
1993
Mebatsion, Teshome | Cox, James H. | Conzelmann, Karl Klaus
From brain samples collected from domestic animals in Ethiopia, two rabies-related viruses were isolated. According to their reactivity pattern with anti-nucleocapsid monoclonal antibodies, they were characterized as Lagos bat virus (isolate Eth-58) and Mokola virus (isolate Eth-16). This classification was confirmed by neutralization experiments with Mokola and Lagos bat specific antisera. Two potent anti-rabies vaccines were unable to protect mice against the two rabies-related viruses. In order to investigate molecular relationships to classical rabies virus, cDNA cloning and sequencing was performed. The RNA genome of both viruses comprises 12 kilobases (kb) and has an organization similar to that of rabies virus with the gene order 3'-N-P-M-G-L-5'. Using virus-specific cDNA as probes in heterologous hybridization experiments, the RNAs of other members of lyssavirus serotypes 2 and 3 were detected. From hybridization experiments and sequence analysis of the 3' terminal 5,5 kb of the genomes, Eth-16 and Eth-58 viruses were shown to be equally genetically distant from rabies virus with 60% nucleotide identity; Eth-16 and Eth-58 had 68% homology.
Mostrar más [+] Menos [-]The (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium) colorimetric assay for the quantitation of Actinobacillus pleuropneumoniae cytotoxin
1993
Chung, W.B. | Backstrom, L.R. | McDonald, J. | Collins, M.T.
Chlamydia psittaci infection and associated infertility in sheep
1993
Papp, J.R. | Shewen, P.E. | Gartley, C.J.
Actinobacillus pleuropneumoniae culture supernatants interfere with killing of Pasteurella multocida by swine pulmonary alveolar macrophages
1993
Chung, W.B. | Backstrom, L. | McDonald, J. | Collins, M.T.
Effects of Pasteurella haemolytica culture supernate on bovine tracheal smooth muscle
1993
Belanger, A. | Harris, W.H. | Yamashiro, S.
Influence of low dietary iron and iron overload on urethan-induced lung tumors in mice
1993
Omara, F.O. | Blakley, B.R.
The predictive value of pelvimetry in beef cattle
1993
Van Donkersgoed, J. | Ribble, C.S. | Booker, C.W. | McCartney, D. | Janzen, E.D.
Lack of effect of recombinant bovine interferon alpha(I)1 in the treatment of experimentally-induced bovine warts
1993
Lassauzet, M.L. | Salamin, P.A.
Detection of Actinobacillus pleuropneumoniae in the porcine upper respiratory tract as a complement to serological tests
1993
Sidibe, M. | Messier, S. | Lariviere, S. | Gottschalk, M. | Mittal, K.R.