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81.
Sturgill TL Giguère S Franklin RP Cohen ND Hagen J Kalyuzhny AE 《Veterinary immunology and immunopathology》2011,140(3-4):237-243
The objectives of the present study were to determine if administration of inactivated parapoxvirus ovis (IPPVO) can decrease the cumulative incidence of pneumonia and increase the number of IFN-γ- and IL-4-secreting cells among foals. Fifty-nine foals were randomly assigned to 2 treatment groups (IPPVO or placebo) prior to birth. At 24-48 h of age, foals received 2 ml of either IPPVO or a placebo by intramuscular injection. Injections were repeated 24h and 8 days later. The number of IFN-γ- and IL-4-secreting cells was measured using a validated ELISPOT assay on blood mononuclear cells collected when the foals were 1-14 days old. Foals were monitored daily for clinical signs of pneumonia and biweekly for lung lesions by ultrasonography. The proportion of foals that developed clinical or ultrasonographic evidence of pneumonia was not significantly different between IPPVO (16 of 28) and placebo (14 of 31). IFN-γ- and IL-4-secreting cells were detected in only 22 and 15 foals, respectively. There was a significant effect of treatment with IPPVO on the number of IFN-γ secreting cells in foals 7- to 14-days-old but not in younger foals. There was no significant effect of treatment with IPPVO on the number of IL-4-secreting cells. The odds of detecting IFN-γ (5.1; 95% CI: 1.5-15) and IL-4 (3.5; 95% CI: 1.1-12) were significantly higher in foals 7-14 days than in younger foals regardless of treatment group. There was no significant association between IFN-γ or IL-4 secretion early in life and subsequent development of pneumonia. 相似文献
82.
Tracey D. Tuberville Terry M. Norton Bradley J. Waffa Cris Hagen Travis C. Glenn 《Biological conservation》2011,(1):175-183
Population manipulations such as translocation are becoming increasingly important tools in the management of rare and declining species. Evaluating the effectiveness of such manipulations requires comprehensive monitoring of population processes, including dispersal, survivorship, and reproduction. We investigated the mating system of a translocated population of gopher tortoises (Gopherus polyphemus) established through multiple releases, which occurred primarily during 1987–1994. During 2006–2007, we sampled and genotyped 27 candidate males (candidate sires), 34 candidate females (candidate dams), and 121 offspring from 19 clutches at five polymorphic microsatellite loci to determine the relative frequency of multiple paternity and to estimate individual reproductive success. Multiple paternity was detected in 57% of clutches genotyped, and females of single-sire clutches and females of multiple-sire clutches were of similar size. Reproductive success varied among male tortoises, and successful sires were significantly larger than males to which no offspring were attributed. Among successful sires, previously established males sired a disproportionate number of the offspring sampled, despite being significantly smaller than subsequently released males. The high variance in individual reproductive success and the apparent reproductive advantage associated with prior residence observed in this gopher tortoise population has important implications for the design of future translocation projects. 相似文献
83.
The location of the breakover of the hoof capsule can be positioned through shoe placement, shoe shape, or trimming on barefoot horses. Placing the breakover in relation to the tip of PIII is a more dependable location than placing breakover guided only by visual evaluation of the hoof capsule. The hoof-pastern axis and the position of the navicular bone will be affected by the distance from the apex of the frog to breakover. The resulting decrease in strain of the deep digital flexor tendon while standing and during movement will decrease inflammation and disease in the equine digit. 相似文献
84.
Summary Attempts were made to increase the starch content of callus tissue from tubers of cvs Lemhi Russet and Russet Burbank by varying
growth regulator concentration, sugar source, sugar concentration, temperature and callus shape. Starch content was always
higher in media containing no growth regulators. Callus spread over the media contained more starch than unbroken rectangular
or cube-shaped callus. Sucrose was superior to glucose and fructose for starch formation. A sucrose concentration of 20 %
produced more starch than lower concentrations. Callus growth decreased as the sucrose concentration increased. ‘Lemhi Russet’
callus incubated with 8 % sucrose at 20, 25 and 30 °C contained 1.2, 0.4 and 0.8 % starch respectively, which was much higher
than in ‘Russet Burbank’ callus. With varying amounts of mannitol as an osmoticum in 8 % sucrose, the most starch was found
in the medium containing 5 % mannitol.
Research Paper 92B2 of the Idaho Agricultural Experiment Station 相似文献
85.
Victor SR Crisóstomo FR Bueno FC Pagnocca FC Fernandes JB Correa AG Bueno OC Hebling MJ Bacci Júnior M Vieira PC da Silva MF 《Pest management science》2001,57(7):603-608
The development of Leucoagaricus gongylophorus, the fungus cultured by the leaf-cutting ant Atta sexdens was inhibited in vitro by synthetic compounds containing the piperonyl group. In addition, worker ants that were fed daily on an artificial diet to which these compounds were added had a higher mortality rate than the controls. The inhibition of the fungal growth increased with the size of the carbon side chain ranging from C1 through C8 and decreasing thereafter. 1-(3,4-Methylenedioxybenzyloxy)octane (compound 5) was the most active compound and inhibited the fungal development by 80% at a concentration of 15 micrograms ml-1. With worker ants the toxic effects started with compound 5 and increased with the number of carbons in the side chain. Thus, for the same concentration (100 micrograms ml-1) the mortality rates observed after 8 days of diet ingestion were 82%, 66% and 42%, for 1-(3,4-methylenedioxybenzyloxy)decane, 1-(3,4-methylenedioxybenzyloxy)dodecane and compound 5, respectively, whereas with commercial piperonyl butoxide the mortality was 68%. The latter compound, which is known as a synergist insecticide, was as inhibitory to the symbiotic fungus as the synthetic compound 5. The possibility of controlling these insects in the future using compounds that can target simultaneously both organisms is discussed. 相似文献
86.
Nielen AL Knol BW van Hagen MA van der Gaag I 《Tijdschrift voor diergeneeskunde》2003,128(19):586-590
The aim of this project, which ran from 1 January 1994 to 1 January 1999 (and which will be continued up to 2004), was to study mortality, disease incidence, and risk factors in a birth cohort of purebred boxer dogs born between January 1994 and February 1995 in the Netherlands (n = 2629). The ancestry of the boxer dogs in the cohort was considered a major risk factor. Special attention was given to genetic disorders, because a system for genetic counselling was being planned; however, non-genetic risk factors were also studied. Participation by breeders and owners of boxer dogs was very high. Pup mortality was 22% and was mainly caused by individual pup factors. Between 2 months and 4 years of age, 123 (7.5%) dogs died; the survival rate was 92.5%. The main causes of death were epilepsy (n = 23), heart disease (n = 22), and traffic injury (n = 13). Over the same age range, on average a boxer dog suffered about 4.25 times from a non-serious disease, mainly of the gastro-intestinal tract, upper respiratory tract, or locomotion system, but 20% had a serious, chronic disease. A relatively high heritability estimate (h2) was found for four diseases: cheilo-palatoschisis (h2 = 0.27), cryptorchism (h2 = 0.24), lesions of cruciate ligaments and menisci (h2 = 0.28), epilepsy (h2 = 0.36). Selection by means of genetic counselling, according to a programme developed on the basis of the results of this study, can reduce the frequency of these genetic diseases in purebred populations of boxer dogs. This genetic counselling programme will also be effective in other breeds of dog because it is based on linking specific pedigree and health information with a generally applicable method of estimating breeding values. 相似文献
87.
Trees on leased land provide an important contribution to Canberra's urban forest and consequently the Australian Capital Territory (ACT) Government introduced legislation to protect urban trees on leased land from unwarranted removal under the Tree Protection (Interim Scheme) Act 2001. This tree protection legislation applies to significant trees, classified using size-based criteria, on leased land for urban and other non-rural purposes. Responsibility resides with the ACT Government to preserve and protect significant trees on leased land in Canberra, until such time as removal is warranted and prudent. On Saturday 18 January 2003, 2 years after the introduction of the tree protection legislation, Canberra experienced a state of emergency when major bushfires swept through the bush–urban interface and penetrated into the western urban area subsequently destroying or damaging over 500 houses. There was a substantial increase in requests lodged under the Act immediately after the fires, but by February 2004 the number of requests returned to February 2002 levels which suggests leaseholder response to the fire declines relatively quickly. The percentage of requests approved (88%) remained relatively constant which indicates that the increased number of applications were for reasons that were considered valid under the Act although it is unlikely that these concerns only became valid during the month proceeding the fire. Dominant genera removed each February from 2002 to 2004 were similar; however, Eucalyptus species have shown a small but significant relative increase although there are insufficient data to conclude this increase indicates an increased aversion to this genus. Future management needs to consider the community perception of trees and temporal reaction to major events. 相似文献
88.
In this study, the application of a qualitative and a quantitative method of analysis to detect genetically modified RR-Soy (Roundup-Ready Soy) in processed foods is described. A total of 179 various products containing soy such as baby food and diet products, soy drinks and desserts, tofu and tofu products, soy based meat substitutes, soy protein, breads, flour, granules, cereals, noodles, soy bean sprouts, fats and oils as well as condiments were investigated following the pattern of the section 35 LMBG-method L 23.01.22-1. The DNA was extracted from the samples and analysed using a soybean specific lectin gene PCR as well as a PCR, specific for the genetic modification. Additional, by means of PCR in combination with fluorescence-detection (TaqMan 5'-Nuclease Assay), suspicious samples were subjected to a real-time quantification of the percentage of genetically modified RR-Soy. The methods of analysis proved to be extremely sensitive and specific in regard to the food groups checked. The fats and oils, as well as the condiments were the exceptions in which amplifiable soy DNA could not be detected. The genetic modification of RR-Soy was detected in 34 samples. Eight of these samples contained more than 1% of RR-Soy. It is necessary to determine the percentage of transgenic soy in order to assess whether genetically modified ingredients were deliberately added, or whether they were caused by technically unavoidable contamination (for example during transportation and processing). 相似文献
89.
In this paper, a statistical framework based upon shift-share analysis is employed to analyse regional differences in Norway
regarding changes in harvesting levels and number of full-time equivalent employees in wood processing. Changes in harvesting
levels and employment differ between regions. A tendency found is that there has been a moderate centralisation in the period
1990–2000 with respect to harvesting levels. The analysis indicates that remote municipalities harvest relatively more in
periods with a high harvesting intensity, while the harvesting level is more evenly distributed among the regions in other
periods. There is, however, no clear picture whether there has been a centralisation or decentralisation regarding woodbased
employment. Differences between regions may therefore be explained by structural factors, for example the degree to which
firms in a particular region concentrate on production of bulky commodities or more customeroriented niche production. 相似文献
90.