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271.
Development of sarcocysts of Sarcocystis levinei in water buffalo infected with sporocysts from dogs
Half a million sporocysts of Sarcocystis levinei obtained from experimentally infected dogs were fed to a buffalo calf, and sarcocysts of this species were recovered from its oesophageal muscles when the animal was killed on the 62nd day of inoculation, thus establishing a buffalo-dog-buffalo cycle. 相似文献
272.
Joshi A Naqvi SM Bag S Dang AK Sharma RC Rawat PS Mittal JP 《Tropical animal health and production》2003,35(3):249-257
The Garole is a prolific but less well known and rare breed of small sheep found in the hot and humid Sunderban region of West Bengal. An ability to breed throughout the year and to graze in knee-deep water, resistance to foot rot and a strong mothering instinct are some of the special features of this breed. Garole rams could provide germplasm to incorporate prolificacy traits by artificial insemination of the nonprolific sheep breeds found in abundance in the semi-arid and arid tropical climates of India. The aim of the present study was to evaluate the semen production by Garole rams maintained in a semi-arid climate for three years and to objectively assess their semen quality by a computer-assisted sperm analysis technique. The donor rams were randomly selected each year from the original flock procured from their natural habitat or from the offspring born at the Institute farm. Semen was collected weekly for three weeks each autumn for three consecutive years from 8 rams each year. The overall means (SD) of the traits that did not differ significantly with age or year were volume, concentration, curvilinear velocity, average path velocity, amplitude of lateral head displacement, beat frequency, motility and the percentages of rapid motile sperms and of slow motile sperms. The age of the rams had a significant effect (p<0.05) on the straight-line velocity but this was not significantly affected by the length of exposure to the semi-arid climate. However, the age and year had significant effects (p<0.05) on linearity, straightness and the percentage of medium motile sperms. It was concluded that Garole rams are capable of producing good-quality semen even after a prolonged period of exposure to a semi-arid tropical climate. 相似文献
273.
R. K. Joshi Rajesh Chandra V. D. P. Rao S. K. Garg 《Tropical animal health and production》1989,21(4):233-235
Summary The coagglutination test was standardised usingStaphylococcus aureus strain Cowan I (containing Protein A) coated with anti-goat pox serum for the detection of goat pox antigen of infected goat skin or kid kidney cell culture antigen. Agglutination was observed within 10 seconds in virus dilutions up to 10–6. As the test is easy to perform it can be used for rapid diagnosis of goat pox.
Prueba De Coaglutinacion: Una Tecnica Diagnostica Simple Y Rapida Para Viruela Caprina
Resumen Se estandarizó la prueba de coaglutinación usando la cepa Cowan I (conteniendo proteína A) deStaphylococcus aureus, cubierto con suero antiviruela caprina, para la detección de antígeno de viruela caprina de la piel infectada o cultivos antigénicos de rinón de cabritillo. Se observó aglutinación a los 10 segundos en dilución de virus hasta 10-6. Como la prueba es fácil de llevar a cabo, ésta puede usarse para el diagnóstico rápido de viruela caprina.
Le Test De lL Coagglutination: Une Technique Simple Et Rapide Pour Le Diagnostic De La Variole Caprine
Résumé L'épreuve de la coagglutination a été standardisée en utlisant une souche Cowan I deStaphylococcus aureus (contenant la protéine A) recouverte avec du sérum variolique anti-caprin pour la détection de l'antigène caprivariolique à partir d'une peau de chèvre infectée, ou d'un antigène provenant d'une culture cellulaire de rein de chevreau. L'agglutination a pu être observée en moins de 10 secondes dans la dilution virale allant jusqu'à 10. Etant donné sa facilité de mise en oeuvre, le test peut être utilisé pour un diagnostic rapide de la variole caprine.相似文献
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277.
Recently, a strong research effort has been focused on applications of beat waves in plasma interactions. This research has important implications for various aspects of plasma physics and plasma technology. This article reviews the present status of the field and comments on plasma probing, heating of magnetically confined and laser plasmas, ionospheric plasma modification, beat-wave particle acceleration, beat-wave current drive in toroidal devices, beat wave-driven free-electron lasers, and phase conjugation with beat waves. 相似文献
278.
The objective of these studies was to evaluate whether exposing primiparous, suckled beef cows to the biostimulatory effect of bulls alters breeding performance associated with an estrus synchronization protocol that included GnRH followed 7 d later by PGF(2alpha) and fixed-time AI (TAI). This was a composite analysis of 3 experiments that evaluated (1) the effects of bull exposure at different days after calving (yr 1); (2) the biostimulatory effects of bull excretory products (yr 2); and (3) the biostimulatory effects of familiar and unfamiliar bulls (yr 3) on the resumption of ovarian cycling activity. In all studies, cows were exposed (biostimulated; n = 94) or not exposed (nonbiostimulated; n = 67) to bulls or excretory products of bulls for at least 60 d before the beginning of the estrus synchronization protocol. Average calving day did not differ among years and was 52 +/- 5 d. Year did not affect the proportions of biostimulated and nonbiostimulated cows that were cycling at the beginning of the estrus synchronization protocol; however, a greater (P < 0.001) proportion of biostimulated than nonbiostimulated cows were cycling at this time. In each year, cows were given GnRH followed by PGF(2alpha) 7 d later. Cows were observed for estrus twice daily (am and pm) after PGF(2alpha). Cows that exhibited estrus before 54, 60, and 64 h after PGF(2alpha) were inseminated by AI 12 h later in yr 1, 2, and 3, respectively. Cows that failed to show estrus were given GnRH and TAI at 62, 72, and 72 h after PGF(2alpha) in yr 1, 2, and 3, respectively. Conception rates were determined by transrectal ultrasonography 35 d after TAI in each year. The percentages of cows that exhibited estrus after PGF(2alpha) and before TAI, the interval from PGF(2alpha) to estrus, and the percentages of cows inseminated 12 h after estrus or at TAI did not differ between biostimulated and nonbiostimulated cows and were 51%, 54.7 +/- 7.3 h, 35%, and 65%, respectively. Conception rates for cows bred by AI 12 h after estrus did not differ between biostimulated and nonbiostimulated cows; however, the TAI conception rate was greater (P < 0.05) for biostimulated cows (57.6%) than for nonbiostimulated cows (35.6%). We conclude that TAI conception rates in an estrus synchronization protocol that includes GnRH followed 7 d later by PGF(2alpha) may be improved by the biostimulatory effect of bulls in postpartum, primiparous cows. 相似文献
279.
Bhave Kaustubh Koilpillai Thilak Pon Jawahar Ragothaman Venkataramanan Sontakke Shivaji Joshi Gautami Ducrocq Vincent 《Tropical animal health and production》2020,52(5):2529-2539
Tropical Animal Health and Production - Semen data comprising of 97,023 ejaculates of 197 bulls from 6 buffalo breeds were analyzed. The traits considered were as follows: ejaculate volume, sperm... 相似文献
280.
A double-pulsar system: a rare laboratory for relativistic gravity and plasma physics 总被引:1,自引:0,他引:1
Lyne AG Burgay M Kramer M Possenti A Manchester RN Camilo F McLaughlin MA Lorimer DR D'Amico N Joshi BC Reynolds J Freire PC 《Science (New York, N.Y.)》2004,303(5661):1153-1157
The clocklike properties of pulsars moving in the gravitational fields of their unseen neutron-star companions have allowed unique tests of general relativity and provided evidence for gravitational radiation. We report here the detection of the 2.8-second pulsar J0737-3039B as the companion to the 23-millisecond pulsar J0737-3039A in a highly relativistic double neutron star system, allowing unprecedented tests of fundamental gravitational physics. We observed a short eclipse of J0737-3039A by J0737-3039B and orbital modulation of the flux density and the pulse shape of J0737-3039B, probably because of the influence of J0737-3039A's energy flux on its magnetosphere. These effects will allow us to probe magneto-ionic properties of a pulsar magnetosphere. 相似文献