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11.
Chicks were injected with L-adrenaline (500 microgram/kg) thrice weekly from hatching for one, two or three weeks. The growth rate of treated chicks was depressed, particularly in the first week. When four-week-old chicks were given nine injections of adrenaline over a three-week period, growth rate was also depressed but less severely. The greater sensitivity of the younger chicks is thought to result from an immature blood-brain barrier. Relative adrenal mass (mg/kg) was generally increased but adrenal cholesterol depletion occurred only in three-week-old birds treated with adrenaline throughout. Plasma glucose and cholesterole concentrations were within the normal range after three weeks of treatment but there was a significant hypolipacidaemia in the younger birds treated for two or three weeks. 相似文献
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ABSTRACT Plant-associated microorganisms are critical to agricultural and food security and are key components in maintaining the balance of our ecosystems. Some of these diverse microbes, which include viruses, bacteria, oomycetes, fungi, and nematodes, cause plant diseases, whereas others prevent diseases or enhance plant growth. Despite their importance, we know little about them on a genomic level. To intervene in disease and understand the basis of biological control or symbiotic relationships, a concerted and coordinated genomic analysis of these microbes is essential. Genome analysis, in this context, refers to the structural and functional analysis of the microbe DNA including the genes, the proteins encoded by those genes, as well as noncoding sequences involved in genome dynamics and function. The ultimate emphasis is on understanding genomic functions involved in plant associations. Members of The American Phytopathological Society (APS) developed a prioritized list of plant-associated microbes for genome analysis. With this list as a foundation for discussions, a Workshop on Genomic Analysis of Plant-Associated Microorganisms was held in Washington, D.C., on 9 to 11 April 2002. The workshop was organized by the Public Policy Board of APS, and was funded by the Department of Energy (DOE), the National Science Foundation (NSF), U.S. Department of Agriculture-Agricultural Research Service (USDA-ARS), and USDA-National Research Initiatives (USDA-NRI). The workshop included academic, industrial, and governmental experts from the genomics and microbial research communities and observers from the federal funding agencies. After reviewing current and near-term technologies, workshop participants proposed a comprehensive, international initiative to obtain the genomic information needed to understand these important microbes and their interactions with host plants and the environment. Specifically, the recommendations call for a 5-year, $500 million international public effort for genome analysis of plant-associated microbes. The goals are to (i) obtain genome sequence information for several representative groups of microbes; (ii) identify and determine function for the genes/proteins and other genomic elements involved in plant-microbe interactions; (iii) develop and implement standardized bioinformatic tools and a database system that is applicable across all microbes; and (iv) educate and train scientists with skills and knowledge of biological and computational sciences who will apply the information to the protection of our food sources and environment. 相似文献
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OBJECTIVE: To calculate the monthly incidence of gastric dilatation-volvulus (GDV) in a population of military working dogs during a 5-year period and determine whether there was an association with synoptic climatologic indices. SAMPLE POPULATION: Medical records of all military working dogs housed at Lackland Air Force Base,Tex, from Jan 1, 1993 to Dec 31, 1997. PROCEDURE: Confirmed cases of GDV were identified from evaluation of medical records and used to calculate incidence of GDV. Factor analysis of local climatologic data was used to classify each day into 1 of 8 meteorologically homogeneous types of days for this location. Occurrence of GDV was compared with frequency of occurrence of synoptic climatologic days. RESULTS: 48 cases of GDV were identified from January 1993 through December 1997 Mean monthly incidence was 2.5 cases/1,000 dogs at risk (range, 0 to 18.5 cases/1,000 dogs; median, 2.5 cases/1,000 dogs). A seasonal increase in incidence of GDV was detected, because half of the episodes were during November, December, and January. An association with a specific synoptic climatologic day was not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Seasonal fluctuations in incidence of GDV may be associated with external factors that precipitate physiologic changes resulting in GDV. Although a specific cause-effect relationship was not documented, clinicians must be alert for the potential of seasonal variation in incidence of GDV and accordingly heighten their index of suspicion for the condition, particularly in populations of dogs that are predisposed to development of GDV. 相似文献
15.
Johnson B Gorman NT Hird JF Wadsworth DE Wells JA Dyson SJ Bleby J 《The Veterinary record》2002,151(8):247; author reply 247
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Rachel C. Murray Michael C. Schramme Sue J. Dyson Marion V. Branch Tony S. Blunden 《Veterinary radiology & ultrasound》2006,47(1):1-16
Palmar foot pain is a common cause of lameness. Magnetic resonance imaging (MRI) has the potential to detect damage in all tissues of the equine foot, but an understanding of the differences in magnetic resonance (MR) images between feet from horses with and without palmar foot pain is required. This study aimed to describe MR findings in feet from horses with no history of foot-related lameness, and to compare these with MR findings in horses with lameness improved by palmar digital local analgesia. Thirty-four limbs from horses euthanized with a clinical diagnosis of navicular syndrome (ameness >2 months duration, positive response to palmar digital nerve blocks and absence of other forelimb problems) (Group L), and 25 feet from age-matched horses with no history of foot pain (Group N) were examined. For each anatomic structure, MR signal intensity and homogeneity, size, definition of margins, and relationships with other structures were described. Alterations in MR signal intensity and homogeneity were graded as mild, moderate, or severe and compared between Groups L and N. Results revealed that there were significant differences in MR images between Groups N and L. Multiple moderate-severe MR signal changes were present in 91% of limbs from Group L and moderate (none were graded severe) in 27% of limbs from Group N. In most Group L limbs, more than three structures and frequently six to eight structures were abnormal. Concomitant abnormalities involved most frequently the deep digital flexor tendon, distal sesamoidean impar ligament, navicular bone, collateral sesamoidean ligament, and navicular bursa (with significant associations in severity grade between these structures), sometimes with involvement of the distal interphalangeal joint and/or its collateral ligaments. It was concluded that findings on MR images were different between horses with and without foot pain, and that pain localized to the foot was associated with MR changes in a variety of structures, indicating that damage to several structures may occur concurrently and that MR imaging was useful for evaluation of foot pain. 相似文献
18.
Sue C. Tongue Dirk U. Pfeiffer Lindsay Heasman Hugh Simmons Stephen J. Ryder 《Livestock Science》2006,105(1-3):120-128
The National Scrapie Plan (NSP) for Great Britain includes selective breeding programmes. These aim to reduce the frequencies of the ovine prion protein (PrP) genotypes at high risk of developing clinical disease (principally those containing the VRQ allele) within the national flock, and select for the low-risk ARR-containing genotypes. The aim of this work was to use available data from embryo transfer programmes in guaranteed scrapie-free environments to investigate whether there was a difference in lamb birth weight associated with the lamb's PrP genotype, which might affect survival. The first analysis utilised data from 355 Cheviot lambs born between 2001 and 2004. The analysis was then repeated using a larger data set of 737 Cheviot, Dorset and Suffolk lambs born between 1999 and 2003. The most important determinants of mean lamb birth weight were litter size, sex and recipient ewe breed, plus lamb breed in the three breed analysis. In both analyses the effects of all these variables are consistent and of the same order of magnitude. In the first analysis there was evidence for an apparent increase in mean lamb birth weight for the ARR-containing genotypes of 0.3 kg (95% C.I. 0.1–0.5 kg). Whereas, in the second data set there was evidence for a decrease in mean lamb birth weight for the VRQ-containing genotypes of − 0.6 kg (95% C.I. − 0.8 to − 0.4 kg). This had been masked in the first analysis by the categorisation of these genotypes with the ARQ/ARQ genotype. Within these flocks, in a scrapie-free environment, neither finding provides support for concerns that selection for low risk ARR-containing genotypes would be detrimental to lamb birth weight, which is considered to be the most important determinant of lamb survival. Extension of this work into field flocks, where scrapie-status cannot be easily assured, will require the collection of sufficient data to adjust for known direct effects as well as any additional potential confounding effects. 相似文献
19.
Reproductive failure in mink and ferrets after intravenous or oral inoculation of Campylobacter jejuni. 总被引:1,自引:0,他引:1 下载免费PDF全文
Four pregnant mink and seven pregnant ferrets, including five with previous exposure and specific antibody, were injected intravenously with 10(8)-10(10) colony-forming units of Campylobacter jejuni. All 11 pregnancies failed 1-16 days after infection, with results ranging from fetal resorption to expulsion of dead or premature living kits. In every case, uterine contents (placenta, uterine fluid and/or kits) were culture-positive for C. jejuni. Three pregnant mink and nine pregnant ferrets, including four with previous exposure and antibody, were fed 10(9)-10(11) C. jejuni. Two of the mink aborted; kits of all three were culture-positive, but those of one female survived. Seven of the nine ferrets aborted, with two having culture-positive uterine contents. None of 28 uninfected ferret control pregnancies ended in abortion. The most prominent histological feature observed was severe placentitis, which appears to be a more likely cause of Campylobacter-induced abortion than direct pathogenic effects on infected kits. These results suggest that infection of mink or ferrets with C. jejuni during pregnancy poses a serious risk of reproductive failure, even for previously exposed females. 相似文献
20.
Miguel Salgado Gustavo Monti Iker Sevilla Elizabeth Manning 《Tropical animal health and production》2014,46(7):1313-1316
Paratuberculosis has long been considered a disease of domestic and wild ruminants only. The known host range of Mycobacterium avium subsp. paratuberculosis (MAP) was recently extended to include non-ruminant wildlife species believed to be exposed to spillover of MAP from infected domestic cattle herds. The aim of the present study was to assess the association between cattle herd MAP infection pressure level and the infection level of a hare population in two dairy farms of southern Chile. Fifty hares from a herd A and 42 hares from herd B were captured and sampled for MAP culture. The results showed a statistically significant association between the cattle herds’ infection prevalence and the hare infection prevalence. 相似文献