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1.
Faecal samples from 434 calves under 1 year of age (307 diarrhoeal and 127 normal) were collected from three dairy farms and one village in selected areas of Bangladesh. The samples were tested by an enzyme-linked immunosorbent assay (ELISA) to detect the presence of rotavirus antigen. Of 402 dairy calves tested, 28 (7.0%) were positive, of which 21 (7.2%) were from diarrhoeic calves and 7 (6.3%) from non-diarrhoeic calves. Rotavirus infection varied from farm to farm (2.7–9.2%) and there was no positive response from any of the 32 village calves. Rotavirus was most commonly found in calves of 1 week of age or less (up to 22.2% in one group) but was not found in any calves later than 6 months of age. More than 80% of rotavirus-positive samples from diarrhoeic calves exhibited a titre of 128 or more (geometric mean 345±4.5), whereas non-diarrhoeal calves had titres less than or equal to 128 (geometric mean=29±1.9), suggesting that rotavirus infection in calves in Bangladesh was mostly associated with diarrhoea.  相似文献   
2.
The responses of four wheat ( Triticum aestivum L.) varieties to soil moisture were determined by measuring plant parameters such as relative leaf water content (RLWC) and the chlorophyll, proline and sugar contents of the leaf over two seasons. Two levels of irrigation treatments were adopted: irrigated and rainfed. The rainfed plants had consistently higher amounts of proline and sugar but lower RLWC and chlorophyll content. As drought intensified, differences between the irrigated and the rainfed plants with respect to all of these characters increased. The RLWC values of the irrigated plants were significantly higher in the morning but lower values were found at noon, showing some recovery in the afternoon.  相似文献   
3.
The herbage intake and grazing behaviour of 4 dry cows on autumn grass receiving 2, 4, 6 or 8 kg concentrates/day, was assessed in a 4×4 Latin Square experiment. Total OM intake increased from 11±5 kg/day with 2 kg concentrates to 13±6 kg/day with 8 kg concentrates. The average supplementary effect was 0±46 kg increase in OM intake/kg OM fed as concentrates. Minutes per day spent grazing decreased from 495 with 2 kg concentrates to 359 with 8 kg. The mean decline was 22 min./kg concentrates or 28 min./kg OM in concentrates eaten. Herbage was eaten at an average rate of 47 min./kg OM.  相似文献   
4.
Antibacterial compounds from the flowers of Alangium salviifolium   总被引:2,自引:0,他引:2  
1-Methyl-1H-pyrimidine-2,4-dione and 3-O-beta-D-glucopyranosyl-(24beta)-ethylcholesta-5,22,25-triene, isolated from the flowers of Alangium salviifolium, showed remarkable antibacterial activities against a number of Gram-positive and Gram-negative bacterial species.  相似文献   
5.
Biological activity of Glechoma hederacea   总被引:2,自引:0,他引:2  
The n-hexane, dichloromethane and methanol extracts of the aerial parts of Glechoma hederacea have been screened for antibacterial and free radical scavenging activity. General toxicity (brine shrimp lethality assay) of these extracts has also been assessed.  相似文献   
6.
7.
Genetic Resources and Crop Evolution - The present investigation was aimed to study the performance of F1 progenies of crosses between Brassica carinata A. Braun and Brassica rapa L. considering...  相似文献   
8.

The meteorological drought dynamics and its impacts on rice productivity has been evaluated for the Indian Summer Monsoon Rainfall (ISMR) season using the standardized precipitation index (SPI) over the middle Gangetic plains (MGP) of Bihar. The meteorological drought over the ISMR period was found to be a recurring phenomenon coinciding with the rice growing season over Bihar. The rice crop has an intensive water requirement; therefore, it is significantly impacted by the meteorological droughts. In the present study, spatiotemporal characteristics viz. intensity, frequency, and probability of meteorological drought has been assessed along with an investigation for significant trends and detection of regime shift points to identify the impact of drought on rice production. For the purpose, SPI-4 derived from high resolution gridded daily rainfall data (0.25°?×?0.25°) from India Meteorological Department (IMD) has been considered to analyse the meteorological drought episodes over agro-climatic zones of Bihar from 1961 to 2019. The regime shifts were determined using the Rodionov test for the drought dynamics and production of rice in Bihar. A moderate to severe drought-prone zone was found over the zone BRZ3B; while zone BRZ2 and BRZ3A showed comparatively a greater number of mild drought events persisting with more than 70% probability of occurrence. An inkling of increasing dependency on groundwater is found, which is in turn governing the rice production regime. The present study shows there is a substantial need for climate resilience and food security policies incorporating the subtle linkage between SPI variability and crop production, especially over rice producing regions of the globe.

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9.
Summary An evaluation was undertaken of the efficacy of vaccination of day-old chicks with the Blacksburg (B1) strain of Newcastle disease virus (NDV) followed at various times by vaccination with the Komarov (K) strain. Antibody was detected by the haemagglutination inhibition (HAI) test one week after vaccination with B1 and titres peaked at three weeks and had declined to undetectable levels by nine weeks.After subsequent vaccination with K strain at five, seven or eight weeks of age levels of HAI antibody (titre 80 to 640) were detected after three weeks. Birds vaccinated at seven weeks were tested for antibody and resistance to challenge beyond 19 weeks of age. In this group the HAI titres remained constant (80 to 640) up to 32 weeks of age and then steadily declined to 10 to 20 at 44 weeks of age.A linear relationship between HAI titre and virus neutralising index (VNI) was demonstrated with a range of selected sera. Only birds with an HAI titre of 80 or greater resisted artificial challenge. It is recommended that, following B1 vaccincation at day-old and K vaccination at seven weeks old, revaccination with K strain should be performed at intervals of not more than seven months.
Proteccion Conferida Mediante Vacunacion Con Las Cepas Blacksburg Komarov Del Virus De Newcastle En Bangladesh
Resumen Se llevó a cabo una evaluación de la eficacia de la vacunación de pollitos de un día, con la cepa Blacksburg (B1) del virus de la enfermedad de Newcastle, seguida de varias aplicaciones vacunales periódicas con la cepa Komarov (K). Se detectaron anticuerpos mediante la prueba de inhibición de la hemaglutinación, una semana después de la vacunación con B1, los títulos alcanzando el pico a las tres semanas y declinaron a niveles no detectables a las nueve semanas.Después de aplicaciones vacunales periódicas con la cepa K, a las cinco, siete u ocho semanas de edad, se detectaron anticuerpos mediante la prueba de inhibición de la hemaglutinación (títulos 80 a 640), después de tres semanas. Las aves vacunadas a las siete semanas, recibieron una descarga y se les hizo prueba de anticuerpos, después de las 19 semanas de edad. En este grupo los títulos de anticuerpos permanecieron constantes (80 to 640) hasta las 32 semanas de edad y después declinaron lentamente a 10 ó 20 a las 44 semanas de edad.Se demostró una relación lineal entre los títulos hallados y el índice viral neutralizante, en un rango de sueros seleccionados. Solamente las aves con títulos de 80 o más altos resistieron la descarga artificial. Se recomienda que, seguidamente a la vacunación con B1 a un día de edad y con K a las siete semanas, las revacunaciones con la cepa K debería hacerse con intervalos de no más de siete meses.

Protection Conferee Contre La Maladie De Newcastle Au Bangladesh Par La Vaccination A L'Aide Des Souches Blacksburg Et Komarov De Virus De La Maladie De Newcastle
Résumé Une evaluation de l'efficacité de la vaccination de poussins d'un jour à l'aide des souches Blackburg (B1) du virus de la maladie de Newcastle, suivie à différents moments par la vaccination à l'aide de la souche Komarov (K), a été entreprise. Les anticorps furent détéctés par inhibition de l'hemagglutination (HAI), une semaine après la vaccination avec la souche B1 et le titre atteignit un pic à 3 semaines pour décliner jusqu'à des niveaux indétectables à neuf semaines. A la suite de vaccinations consécutives avec la souche K à cinq, sept ou huit semaines, les niveaux d'anticorps HAI furent détectés après trois semaines. Les oiseaux vaccinés à sept semaines furent examinés pour les anticorps et la résistance à une épreuve au delà de 19 semaines d'âge. Dans ce groupe les titres HAI sont restés constants (80 à 640) jusqu'à l'àge 32 semaines, puis ont diminué régulièrement jusqu'à 10 à 20 à l'âge de 44 semaines.Une relation linéaire entre le titre HAI et l'index de neutralisation du virus (VNI) a été démontrée sur une gamme de sérums choisis. Seuls les oiseaux ayant un titre HAI de 80 ou plus ont résisté à l'épreuve artificielle. On recommande que, après une vaccination B1 à un jour, et une vaccination K à l'âge de sept semaines, une revaccination K soit réalisée à des intervalles n'excédant pas sept mois.
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10.
Pollen tube growth in crosses between Porteresia coarctata and Oryza sativa   总被引:1,自引:0,他引:1  
Summary Comparative study with fluorescence microscopy revealed that the pollen tubes of the self-pollinated rice variety BR-9 reached the ovary within 75 min after pollination. In P. coarctata it took 150 min. In the cross between P. coarctata and BR-9, pollen tubes reached the ovary in 165 min but seed setting was not observed. In the cross between BR-9 and P. coarctata, small and deformed pollen tubes were formed and they failed to grow through the stylodium.  相似文献   
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