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91.
SUMMARY The response of sheep to a recombinant multivalent footrot vaccine containing pilus antigens was examined after the administration of two doses of vaccine at Intervals ranging from 2 to 52 weeks. Agglutinating antibody titres were measured 3 weeks after the second vaccination and showed that lengthening of the interdose interval results in higher agglutinin titres. The capability of sheep to mount an increasingly strong immune response as the interval between doses is increased provides an opportunity to maximise the usefulness of vaccination by administering the first dose well before an expected footrot transmission period. This advantage of increasing the interdose interval has not been reported for traditional, whole-cell footrot vaccines, and use of the new pilus vaccine in this manner may improve prospects for disease control. Furthermore, sheep given a third dose either 6 or 12 months after their initial two-dose vaccination program achieved significantly higher titres than those elicited after the second dose, suggesting the likelihood of further improvement in disease control in successive seasons. 相似文献
92.
A Mezalira D Dallanora ML Bernardi I Wentz FP Bortolozzo 《Reproduction in domestic animals》2005,40(1):1-5
This study was carried out to evaluate the effects of the sperm cell dose and semen backflow on the pregnancy rate and number of embryos of sows inseminated once at 0-24 h before ovulation, using an intrauterine technique. The results were analysed from a total of 211 sows assigned to three groups inseminated with doses of 0.25 x 10(9) (T1), 0.5 x 10(9) (T2) and 1.0 x 10(9) (T3) spermatozoa. Semen backflow was observed in 95% of the females (143/151) evaluated for this purpose. The percentage of semen backflow is close to two-third of the volume and the percentage of sperm is around 15% of the infused sperm dose. Intrauterine insemination can be successfully performed provided that at least 0.5 billion of sperm cell dose is infused at an interval of 0-24 h before ovulation. 相似文献
93.
Adult Haemonchus contortus (Rud., 1803) has been investigated for its ability to utilize lipids with regard to the total lipids, sterols, free fatty acids, acylglycerols and phospholipids produced during incubation in vitro. All these components exhibit extensive fluctuations, decreasing at some times and increasing at others, thus indicating both biosynthesis and utilization. Also, changes in fatty acid components of total lipids have been analyzed by gas liquid chromatography. These observations indicate that H. contortus is capable of utilizing 16:0, 18:0, 18:1, 18:2, 20:0, 20:un1, 20:un2, 21:0, 21:un1, 21:1, 21:un2, 22:un1, 22:3, 22:?, 22:un2 and 24:3 fatty acids. At the same time, because of large increases in 15:0, 16:0, 18:0, 18:?, 18:1, 18:2, 20:0, 20:un1, 20:un2, 21:0, 21:un1, 21:1 and 21:un2 acids, it is postulated that these acids are synthesized by adult H. contortus. 相似文献
94.
Do socio-psychological factors matter in agroforestry planning? Lessons from smallholder traditional agroforestry systems 总被引:1,自引:0,他引:1
Most of the well planned rural development forestry programs of the 1970s, and agroforestry in particular, were either not
adopted by the intended beneficiaries or failed to meet the needs and aspirations of the rural people, particularly in the
developing countries. The reasons for non-adoption in some cases appear to be technical, bio-physical, social and economic
(termed as rational reasons by the planners), but in other situations the reasons are not so easily recognisable and comprehended
(termed irrational reasons). These irrational reasons are the perceptions and attitude of the farmer towards farm practices,
and their role in agroforestry planning has remained almost completely neglected. The present study is based on a household
survey of the farmers in traditional agroforestry systems of Western Himalaya and investigates the importance of perceptional
and attitudinal aspects of the farmers with regard to agroforestry adoption and extension. In the present study, farmers’
perceptions of restrictions on felling of trees from their own land and attitudes towards agroforestry were the most important
sociopsychological factors which influenced tree growing. This study implies a need to take into account the socio-psychological
factors of the farmers for planning socially acceptable agroforestry programs. The importance of study of various de jure rules and regulations controlling the use of on-farm tree resources and related exemptions and their association with farmers’
perceptions and tree growing is highlighted to develop policies to encourage tree growing in agroforestry. 相似文献
95.
96.
The presentation, treatment and outcomes of 33 ingluvial fibrous foreign bodies in cockatiels (Nymphicus hollandicus) are described. Vomiting, lethargy and weight loss were the most common presenting signs. Diagnosis was made on palpation of a mass in the crop (ingluvies). Both surgical and non‐surgical treatment regimens were evaluated. The overall mortality rate was 33%, suggesting fibrous materials are not safe for cockatiels to groom or ingest and should not be offered as cage accessories. 相似文献
97.
Kishor Bhandari Pankaj Sood Pawan K. Mehta Amit Choudhary Chandra S. Prabhakar 《Phytoparasitica》2009,37(4):317-322
A granulosis virus strain infecting Pieris brassicae (PbGV) was isolated from the dry temperate region of northwestern Himalayas as a potential microbial agent for its management.
The effect of different botanicals (having insecticidal action against P. brassicae) on the bioefficacy of PbGV was evaluated under laboratory conditions using leaf disc bioassays on cabbage for improving
the insecticidal performance of the PbGV. The synergistic action of different botanical extracts was evident in terms of reduction
in LC50 values against different botanical extracts. Among different extracts, petroleum-ether extract of neem seed kernel (NSK)
when combined with PbGV resulted in maximum reduction of LC50 value (4.39 × 102 occlusion bodies [OBs] ml−1) followed by methanolic extract (7.38 × 102 OBs ml−1) and aqueous extract (9.36 × 103 OBs ml−1) as compared with PbGV alone (1.85 × 104 OBs ml−1) for 2nd instar larvae of the test insect. These trends were found analogous in cases of 3rd and 4th instars of P. brassicae with different solvent extracts of NSK. The other botanicals evaluated, viz., Eupatorium and Artemesia, also resulted in reduction of LC50 values for 2nd, 3rd and 4th instars as compared with PbGV alone when different extracts were combined with virus for bioassays.
The studies suggest that the PbGV in combination with botanical pesticides could be more useful as a bio-pesticide against
cabbage butterfly (P. brassicae) in IPM programs. 相似文献
98.
A study was conducted in Kullu district in the province of Himachal Pradesh in Indian Western Himalaya, to investigate the
perceptions of Indian foresters about aspects of forest management relevant for effective Joint Forest Management (JFM). A
lack of uniform understanding was found amongst forestry staff about almost all the studied issues pertaining to JFM. A need
is identified to emphasise social aspects in the training of the foresters (including in-service training), along with the
existing silvi-technical aspects. For JFM success, measures need to be devised to reduce the political interference in JFM,
reduce hierarchical rigidity, and increase interaction between field staff and the administrative hierarchy. Strategies should
be devised to make JFM participants as well as forestry staff equally responsible to honour their commitments with respect
to JFM.
相似文献
Kamal Kishor SoodEmail: |
99.
EJ Steig EJ Brook JWC White CM Sucher ML Bender SJ Lehman DL Morse ED Waddington GD Clow 《Science (New York, N.Y.)》1998,282(5386):92-95
Central Greenland ice cores provide evidence of abrupt changes in climate over the past 100,000 years. Many of these changes have also been identified in sedimentary and geochemical signatures in deep-sea sediment cores from the North Atlantic, confirming the link between millennial-scale climate variability and ocean thermohaline circulation. It is shown here that two of the most prominent North Atlantic events-the rapid warming that marks the end of the last glacial period and the Bolling/Allerod-Younger Dryas oscillation-are also recorded in an ice core from Taylor Dome, in the western Ross Sea sector of Antarctica. This result contrasts with evidence from ice cores in other regions of Antarctica, which show an asynchronous response between the Northern and Southern Hemispheres. 相似文献
100.
Gibberellic acid (GA3) induced changes in proanthocyanidins and malt quality of two and six-row husked barleys 总被引:1,自引:0,他引:1
Yadav SK Luthra YP Sood DR Aggarwal NK 《Plant foods for human nutrition (Dordrecht, Netherlands)》2000,55(2):87-96
Analysis of husked barleys for proanthocyanidins and malt qualityattributes has shown that not a single variety is free ofproanthocyanidins. The proanthocyanidins in barley grains variedfrom 3.85 to 4.94 mg/g as catechin equivalent. The concentrationof proanthocyanidins decreased, while total soluble sugars, reducingsugars, diastatic power and -amylase activity increasedduring maltings as well as with exogenous gibberellic acid (GA3)application. Alfa 93 (two-row) and RD2560 (six-row) varietiesappeared to be superior for malting and brewing purposes on thebasis of proanthocyanidins, total phenols, diastatic power and-amylase activity. It is suggested that exogenous applicationof GA3 at 15 ppm may be useful for producing good quality maltfrom barley grains. 相似文献