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31.
Surveys were made at the end of the 1990 and 1991 growing seasons for root-inhabiting fungi in the genera Fusarium, Cylindrocarpon and Pythium from the roots of one year-old container-grown Douglas-fir and spruce seedlings grown under greenhouse conditions. In the 1990 survey of four nurseries, it was found that 61–97% of both Douglas-fir and spruce roots were colonized with Fusarium, Cylindrocarpon or Pythium. There were significantly (p0.05) more Douglas-fir roots than spruce roots colonized by Fusarium at all nurseries, however, there were significantly (p0.05) more spruce roots than Douglas-fir roots colonized by Cylindrocarpon and Pythium. Root colonization of Douglas-fir and spruce by the three fungal genera during 1991 varied from 0–82% at three nurseries, however, only at a south coastal nursery was there significantly (p0.05) more spruce than Douglas-fir roots colonized by Cylindrocarpon. Significantly more seedlings were infected in 1990 than in 1991. In 1991, there were few significant differences between Douglas-fir and spruce, in the percentage of seedlings with colonized roots and in the percentage of growth medium colonized by the fungi. However, there were significant differences between nurseries. 相似文献
32.
The ethyl acetate, acetone and methanol extracts of Wrightia tinctoria bark showed antinociceptive activity on acetic acid-induced writhing test in mice, their effects being comparable to that of acetylsalicylic acid. 相似文献
33.
The aerial parts of Malvastrum coromandelinum showed antinociceptive activity in the 0.6% acetic acid-induced writhing test in mice, the effects of acetone extract (200 mg/kg, p.o.) being comparable with acetylsalicylic acid (100 mg/kg, p.o.) 相似文献
34.
Shade is one of the important limiting factors in intercropped agro-ecosystems. Objective of this work is to analyze the role
of eight foliar traits of juvenile plants of five different species of Jasminum grown under coconut shade. The results reveal the shade tolerant J. pubescence to produce more number of nodes and longer shoots in all the three seasons studied. J. grandiflorum produced longer leaves and internodal distance than other species tested. Winter season shoots were longer with more number
of nodes and longer internodal distances than rainy season. Results are discussed in relation to the adaptive behavior of
plants to shade. 相似文献
35.
Ilias S Frydas Ivan Trus Lise K Kvisgaard Caroline Bonckaert Vishwanatha RAP Reddy Yewei Li Lars E Larsen Hans J Nauwynck 《Veterinary research》2015,46(1)
In this study, the pathogenic behavior of PRRSV 13V091 and 13V117, isolated in 2013 from two different Belgian farms with enzootic respiratory problems shortly after weaning in the nursery, were compared with the Belgian strain 07V063 isolated in 2007. Full-length genome sequencing was performed to identify their origin. Twelve weeks-old pigs were inoculated intranasally (IN) with 13V091, 13V117 or 07V063 (9 pigs/group). At 10 days post inoculation (dpi), 4 animals from each group were euthanized and tissues were collected for pathology, virological and serological analysis. 13V091 infection resulted in the highest respiratory disease scores and longest period of fever. Gross lung lesions were more pronounced for 13V091 (13%), than for 13V117 (7%) and 07V063 (11%). The nasal shedding and viremia was also most extensive with 13V091. The 13V091 group showed the highest virus replication in conchae, tonsils and retropharyngeal lymph nodes. 13V117 infection resulted in the lowest virus replication in lymphoid tissues. 13V091 showed higher numbers of sialoadhesin− infected cells/mm2 in conchae, tonsils and spleen than 13V117 and 07V063. Neutralizing antibody response with 07V063 was stronger than with 13V091 and 13V117. It can be concluded that (i) 13V091 is a highly pathogenic type 1 subtype 1 PRRSV strain that replicates better than 07V063 and 13V117 and has a strong tropism for sialoadhesin− cells and (ii) despite the close genetic relationship between 13V117 and 07V063, 13V117 has an increased nasal replication and shedding, but a decreased replication in lymphoid tissues compared to 07V063.
Electronic supplementary material
The online version of this article (doi:10.1186/s13567-015-0166-3) contains supplementary material, which is available to authorized users. 相似文献36.
Beef quality traits of heifer in comparison with steer,bull and cow at various feeding environments
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Bandugula Venkata Reddy Allur S. Sivakumar Dawoon W. Jeong Yang‐Byung Woo Sang‐June Park So‐Young Lee Ji‐Yeon Byun Chang‐Ho Kim Soo‐Hyun Cho Inho Hwang 《Animal Science Journal》2015,86(1):1-16
The present review has been focused largely on the sex type differences in beef quality among heifers, cows, steers and bulls in various feeding environments. Genetic groups, feeding systems and gender are the major factors that change carcass characteristics and fatty acid profiles of cattle. Studies identified that heifer beef has super characteristics in eating quality and a better healthy composition in fatty acids than steer, cow and bull. Diet influences the variation of fatty acid profile; particularly the level of polyunsaturated fatty acids (PUFA) interacts with breed and sex. Animals finished in pasture systems were reported to show better ratios of PUFA/ saturated fatty acids and n‐6/n‐3. Carcasses of roughage‐fed beef are lighter and have less marbling and lower quality grades but have higher cutability than carcasses of grain‐fed bulls. Heifers and cows are reported to deposit more fat than steers and bulls. Among males, lower production of testosterone by steers favors more fat thickness compared with bulls. Marbling greatly varies among cattle belonging to different sexes, and particularly, females have genetic makeup that efficiently controls deposition. The current review identified that heifers can be a premium beef brand, while steer beef currently take a large part of market share across the world. 相似文献
37.
N. Vinod Kumar B. Sreedevi A. Karthik S. Vijaya Lakshmi A. Geetha Reddy D. Sreenivasulu 《Veterinary research communications》2014,38(4):323-328
An outbreak of sheep associated malignant catarrhal fever in crossbred cattle in a village of Andhra Pradesh, southern India, affected thirteen adult cows and two calves from a population of forty animals. All the affected animals were died between December and January 2013–14. The clinical and gross postmortem findings were typical of MCF in Indian crossbred cattle. Migrating sheep flocks were suspected source of infection for the cattle. The diagnosis was confirmed by heminested PCR in all the affected cattle and the suspected sheep flock. The PCR provided evidence of ovine herpes virus type 2. 相似文献
38.
M.N. Khan P.K. Reddy R.L. Renaud J.F. Leatherland 《Fish physiology and biochemistry》1997,16(3):197-209
The effect of cortisol on the in vitro metabolism of [3H]17-hydroxyprogesterone ([3H]17OHP) was studied during embryonic development of Arctic charr (Salvelinus alpinus) and rainbow trout (Oncorhynchus mykiss). In the absence of cortisol, rainbow trout embryos metabolized [3H]17OHP largely to androstenedione (A4) and androstenetrione (11-KA) with a minor conversion to 17,20ß-dihydroxy-4-pregnen-3-one (17,20P). In the presence of cortisol, this biosynthesis was inhibited. On the other hand, cortisol had no apparent inhibitory effect on the nature of metabolism of [3H]17OHP by Arctic charr embryos. In these embryos [3H]17OHP was metabolized mainly to 17,20P with a minor conversion to A4 and without the formation of 11-KA that was seen in rainbow trout.When incubated in the presence of [3H]cortisol both Arctic charr and rainbow trout embryos produced 11ß-hydroxyandrostenedione (11ß-OHA) as the major metabolite, with a minor conversion to an unknown steroid. The catabolism of the cortisol by salmonid embryos may reflect the ability of the embryo to inactivate or detoxify cortisol to protect itself from the adverse effects of this biologically potent steroid hormone The study indicates the existence of species-specific differences in the nature of metabolism of [3H]17OHP and the inhibitory effect of cortisol on this metabolism. 相似文献
39.
Furrows are widely used in rainfed areas of semi-arid India for soil and water conservation. The orientation of furrows, either down or across slope, and their spacing influence the effectiveness of furrows as soil and water conservation measures. We evaluated treatments with furrows aligned down and across 3% sloping land at spacings of 90, 60 and 30 cm under simulated rainfall intensities of 80 and 100 mm/h on a shallow Alfisol. A bare plot without any furrows was considered as a control. A large (24 m × 3 m) rainfall simulator developed at the Central Research Institute for Dryland Agriculture (CRIDA), Hyderabad, was used for this controlled study. Run-off was measured by a calibrated tipping bucket run-off recorder. The effects of the treatments on peak flow rate (L/s), sediment loss with run-off water (kg/ha/mm), peak sediment concentration (g/L), run-off (per cent rainfall) and time to peak (min) were investigated. When compared with the control (no furrows), across slope furrowing with 60- and 30-cm spacing reduced sediment yields by 19.9 and 21.3 kg/ha/mm of run-off, respectively, under a rainfall intensity of 80 mm/h and 24 and 25.3 kg/ha/mm of run-off, respectively, under a rainfall intensity of 100 mm/h. For the control, sediment loss was 50.72 kg/ha/mm run-off and 56.68 kg/ha/mm run-off for rainfall intensities of 80 and 100 mm/h, respectively. Similar trends were recorded from observations of peak flow, time to peak and peak sediment concentration. Run-off hydrographs demonstrated the conservation value of across slope furrowing by delaying run-off initiation, reducing run-off and slowly releasing the run-off after the cessation of rainfall. The results show that furrow orientation has major effects on reducing run-off, whereas furrow spacing has insignificant effects. 相似文献
40.
Rambouillet crossbred ewe lambs were used to evaluate the effect of repeated restraint and isolation stress (RIS) on endocrinological and immunological functions. Lambs were blocked by weight and assigned to either RIS (n = 6) or to control (CON; n = 6) treatments. All lambs were tethered in environmentally controlled rooms at 22 degrees C with constant light and, at this time (d 0), were given 1 mg of ovalbumin in adjuvant. On d 12, catheters were placed nonsurgically into the jugular vein of all lambs, and they were reimmunized with .5 mg of ovalbumin in incomplete adjuvant. Each lamb in the RIS treatment group was removed from its home stanchion, isolated from visual and tactile (but not auditory and olfactory) contact with other lambs, and restrained for 6 h on d 14, 15, and 16. Lambs in CON treatment remained undisturbed in their home stanchions. Lymphocyte blastogenic function and production of interleukin-2 (IL-2) were assessed in samples of blood collected before and at the conclusion (0 and 6 h) of each of the three stress bouts. In addition, ACTH and cortisol secretion in response to RIS was evaluated in samples of plasma and serum collected at .5-h intervals on the first and last days of stress (d 14 and 16). Finally, antibody production in response to immunization against ovalbumin was assessed in samples of serum obtained 14 d after reimmunization on d 12 of the study. Polynomial curves fit to the ACTH and cortisol data differed (P less than .005) on both d 14 and 16 between RIS and CON treatments.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献