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991.
992.
Vijay P. Singh 《Agricultural Water Management》1980,2(4):271-288
Using a linear advance function, a derivation of shape factors for border irrigation advance is presented. Using the proposed derivation, irrigation advance length is predicted for two sets of data reported in the literature. A close agreement is found between observations and predictions. Results of this study are compared with those of others for the same data. 相似文献
993.
994.
Immunological relationship between strains of Theileria annulata Dschunkowsky and Luhs 1904 总被引:1,自引:0,他引:1
B S Gill G C Bansal Y Bhattacharyulu D Kaur A Singh 《Research in veterinary science》1980,29(1):93-97
The immunological relationship between the Ludhiana and Hissar strains, and between the Uruli-Kanchan, Bangalore and Jaipur strains of Theileria annulata was studied. Calves were immunised against the Ludhiana strain by the infection-treatment method, against the Uruli-Kanchan strain by the infection-treatment method or by untreated low-grade infection and against the Jaipur strain by untreated low-grade infection. After 45 days, groups of immune calves and susceptible controls were challenged with 10-tick equivalent stabilates. The ensuing host responses, body temperature, swelling of the regional lymph node, appearance of schizonts in the regional lymph node and piroplasms in blood and mortality, were studied. All five strains proved very virulent and produced severe disease in susceptible calves. Immunisation with the Ludhiana, Uruli-Kanchan and Jaipur strains conferred absolute protection against severe homologous challenges. Immunisation with the Ludhiana and Uruli-Kanchan strains conferred substantial protection against heterologous challenges with the Hissar strain, and the Bangalore and Jaipur strains, respectively. Immunisation with the Uruli-Kanchan strain gave less protection against heterologous challenge with the Jaipur strain and vice versa as some of the challenged calves showed slight swelling of the regional lymph node, two had fever, all exhibited a low-grade parasitaemia and four developed anaemia. 相似文献
995.
Response of timely and late seeded wheat (Triticum aestivum L.) and barley (Hordeum vulgare L.) to three levels of irrigation and four rates of nitrogen was investigated under pre-seeding irrigation. Water extraction pattern and water use of these crops varied markedly. Barley outyielded wheat by 27 and 9%, but used 9 and 21 mm less water, when one and two irrigations were given at critical stages, respectively. These results indicate the possibilities of considerable saving of water (100 mm) for barley without any decrease in grain yield and increased water-use efficiency (WUE) of wheat and barley by irrigating at critical stages as compared to irrigation at 75% depletion of available soil water (ASW). In general WUE decreased with increase in irrigation frequency and delay in seeding.Nitrogen fertilization with marginal additional water use (4–9%) increased yield linearly (45–98%) and thus increased WUE of wheat and barley. This additional water was extracted from below 60 cm depth at tensions ? 1.5 MPa and particularly in maximum growth and reproductive stages. These results suggest that barley should be preferred to wheat under medium to severe water stress and late seeding conditions. 相似文献
996.
997.
K. V. Singh Omar A. Osman Ivon F. El Cicy Thanaa I. Baz 《Canadian journal of veterinary research》1967,31(11):295-298
The transfer of maternal antibodies to Friesian and buffalo calves born of dams vaccinated against rinderpest was through colostrum only. Colostral antibody titers at the time of parturition were higher than the serum titer. Two hours after suckling, a high level of rinderpest neutralizing antibodies was detected in the sera of newborn animals. The half-life of maternal antibodies in buffalo and Friesian calves was found to be approximately 33 and 29 days respectively. By the age of 7-8 months, 60 per cent of buffalo calves and 80 per cent of Friesian calves had no detectable levels of rinderpest neutralizing antibody. 相似文献
998.
999.
1000.