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V. Ayyagari S. C. Mohapatra Dr. A. Venkatramaiah T. Thiagasundaram D. Choudhuri D. C. Johri P. Renganathan 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1980,57(6):277-283
Summary Responses from four generations of index selection for egg production to 280 days of age in four White Leghorn populations have been presented. A pedigreed randombred population derived from one of the lines was reared with the selected lines to measure the environmental trend. The magnitude of total as well as average response although varying from population to population was positive in all the lines studied. Close correspondence between predicted and realized gains indicated that natural selection, genotype environmental interactions and environmental fluctuations were unimportant during the course of selection. Realized heritabilities agreed fairly well with the estimated heritabilities in at least three out of four populations studied. Probable reasons for variable and insufficient response were investigated. 相似文献
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Three experiments were conducted to examine the progestogen plus PMSG treatment for its effectiveness in inducing synchronous puberty in prepuberal zebu heifers in three different seasons. In Experiment 1, ten Ongole heifers (age 21 months) were treated with Norgestomet implants for nine days and an intramuscular injection of 400 IU of PMSG two days before implant removal. Ten heifers (age 25 months) were kept as untreated controls. Animals were inseminated 12 h after detection of cyclic estrus (not bred at induced estrus) until all animals conceived. The proportion of treated animals showing estrous, ovulatory, and cyclic activity were 100%, 75% and 25% respectively, while the average age at first conception was significantly less (P < 0.05) than in the control group. In Experiment 2, 18 Ongole heifers (age 22 months) were divided into treatment and control groups. Fixed-time inseminations were done 48 and 72 h after implant removal and 12 h after being detected in heat at other times. Estrus was seen in all while 63% became pregnant (P < 0.05). At the end of the 100-day experiment, the percent pregnant were 33 and 63 in the control and treatment groups, respectively. In the third study, twenty-six Ongole heifers (age 22 months) were assigned to treatment and control groups. Eighty-eight percent of the animals exhibited estrus, 75% ovulated (P < 0.01) and 25% conceived to fixed-time insemination. The pregnancy rate at the end of the experiment was 10 and 56% (P < 0.01) respectively in control and treated groups. Estrous response and fertility were better in the cooler month (February) and the treatment imposed in the hotter month (May) resulted in a significantly higher (P < 0.05) age and body weight at conception. 相似文献
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A. Venkatramaiah S. C. Mohapatra R. Sinha V. Ayyagari D. Choudhuri 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1986,72(1):129-134
Summary Two sublines from each of four flocks of White Leghorn were subjected to two cycles of selection for part year egg number and part year egg mass. A family index (combined selection) was the selection criterion for each of the two traits. The generation means of an unselected pedigreed randombred control, bred and maintained along with the selected sub-lines, were used for correcting short term environmental trends. The sublines selected for a common selection criterion were considered as replicates. The control corrected generation means, when averaged over replicates, gave the mean direct and correlated responses for the selected and different unselected traits. The average genetic change per generation was 2.16 eggs in egg number selected sublines and 146 g of egg mass in egg mass selected sublines. The direct response marginally exceeded the correlated response for both part period egg number and egg mass seen in the corresponding sublines. Except for egg weight the correlated responses for different unselected traits were in the same direction in both egg number and egg mass selected sublines. While the egg weight in egg number lines did not change, its response was positive in egg mass selected lines. A comparison between the lines revealed that the egg mass selected lines matured later and laid heavier but slightly less numerous eggs than the egg number selected sub-lines. 相似文献
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Yeti Dana Rao Ayyagari Venkata Sekhar Vandana Ravi Kumar Valluri Ravi Kumar Nutalapati Venkatramaiah Nalluri Purnachand Yerramreddy Gandhi Nalluri Veeraiah 《Luminescence》2024,39(1):e4603
In this study, a glass system based on heavy metal oxides, namely Pb3O4–Sb2O3–SiO2, was prepared with Ho2O3, Er2O3, and Tm2O3 as dopants. The prepared glass were characterized using X-ray diffraction (XRD) and infrared (IR) studies. The luminescence efficiencies of the three rare earth ions viz., Ho3+, Er3+, and Tm3+ in the glass system were investigated, specifically focusing on green (Ho3+, Er3+), blue (Tm3+), and near-infrared (NIR) emissions. The optical absorption (OA) and photoluminescence (PL) spectra of RE mixed glass displayed strong bands in the visible and NIR regions, which were analyzed using the Judd–Ofelt (J–O) theory. The J–O coefficients (Ωλ) were found to be in the order of Ω2 > Ω4 > Ω6 for all the three glass. Notably, the Tm3+-doped glass exhibited the lowest Ω2 value, which was attributed to a larger degree of disorder in the glass network due to lower fractions of Sb5+ and Pb4+ ions that take part in the glass network forming. This conclusion was arrived based on the IR studies. Furthermore, the quantitative analysis of PL spectra and decay curves indicated that SbHo and SbEr glass were suitable for efficient green emission, while SbTm glass is a promising choice for blue laser emission. 相似文献
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Pilli Pavani Koteswari Devi Ayyagari Venkata Sekhar Valluri Ravi Kumar Gnanamuthu Sahaya Baskaran Nutalapati Venkatramaiah Vandana Ravi Kumar Nalluri Veeraiah 《Luminescence》2023,38(4):450-461
Li2O-HfO2-SiO2-Tm2O3:Au2O3 glass samples (containing fixed content of Tm2O3 and different concentration of Au2O3) were prepared and characterized. Bearing of Au0 metallic particles (MPs) on improving blue emission of thulium ions (Tm3+) ions was explored. Optical absorption (OA) spectra exhibited multiple bands excited from 3H6 of Tm3+. Additionally, a broad peak in the wavelength range 500–600 nm due to surface plasmon resonance (SPR) of Au0 MPs was noticed in the spectra. Photoluminescence (PL) spectra (of thulium free glasses) indicated a peak in the visible range due to sp → d electronic transition of Au0 MPs. Luminescence spectra of Tm3+ and Au2O3 co-doped glasses exhibited intense blue emission with substantial increase of intensity with increase of Au2O3 content. Bearing of Au0 MPs on the reinforcement of blue emission of Tm3+ was discussed in detail with kinetic rate equations. 相似文献
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