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71.
1 摘要 本研究采用分析粪样、试验末体重和超声波检测的方法评定百乐(R)系列有机微量元素对生长肥育猪粪矿物元素(铜、铁和锌)排泄量以及生长性能和肉质的影响(n=528).  相似文献   
72.
Five dogs and four cats from Germany suffering from encephalitis revealed positive immunoreactivity using two West Nile virus (WNV) specific monoclonal antibodies in brain and in kidney. However, WNV-infection could not be confirmed by additional PCR analyses. This study indicated that positive immunoreactivity for WNV in dogs and cats must be interpreted cautiously and should be confirmed by a second virus-specific technique.  相似文献   
73.
This report aims to describe the first case of muscular and collagenous choristoma in a dog. A 10-yr-old female mixed-breed dog presented with lateral recumbence, vocalization, positional vertical nystagmus, divergent strabismus, anisocoria, and status epilepticus. The clinical condition evolved to stupor and ultimately, death. Necropsy revealed a white mass causing an irregular increase in the volume of the cerebellar vermis. In histological analysis, a well circumscribed, unencapsulated mass was observed in the cerebellum, consisting of fibers of striated skeletal muscle and collagen fibers, mostly mineralized. Based on the histopathological and histochemical findings, a diagnosis of muscular and collagenous cerebellar choristoma was made.  相似文献   
74.
An information management system is described that combines information on physical, biological and financial aspects of market hog production. Data collection methods are described. Data on feed use were the most difficult to collect reliably on-farm. Off-farm, it was critical that health data at slaughter be obtained without disrupting normal hog marketing routines. A summary of diseases observed in market hogs at slaughter is provided. Sample size estimations to achieve statistical confidence in market hog disease prevalence rates at slaughter are presented for number of shioments per farm per year and number of hogs per shipment. Results indicate that slaughter health checks should be performed at least four times annually and at least 50 hogs should be evaluated per shipment. Recommendations for future efforts include decreasing the total amount of data to be collected and improving producer incentives to collect data.  相似文献   
75.
76.
Tryptophan (Trp) and its metabolites, especially indole-3-acetic acid (IAA), are considered to be potential precursors of 2-aminoacetophenone (AAP), an aroma compound that causes an "untypical aging off-flavor" (UTA) in Vitis vinifera wines. In this study, RP-HPLC with fluorescence detection was used for the qualitative and quantitative analysis of Trp and Trp metabolites in grape musts and wines to which different viticultural measures had been applied (time of harvest, soil treatment, leaf plucking, vine prune). An alkaline hydrolysis was developed to release bound IAA and Trp. A sensitive and selective determination of different Trp metabolites was achieved after solid phase extraction using a strong anion exchange material. In the examined grape musts, more than 95% of the total IAA was bound either as ester conjugate or as amide conjugate. Free IAA and other Trp metabolites were below the detection limit (<3 microg/L) or could be determined only in traces. Their amounts increased significantly during fermentation, whereas the amount of Trp decreased. It could be shown that the different viticultural measures applied (except the vine prune) as well as the climatic conditions of the vintage exhibited significant influences on the amounts of Trp and Trp metabolites in grape musts or wines.  相似文献   
77.
A 5-year-old Hereford cow was donated to Oregon State University, College of Veterinary Medicine. Two weeks before presentation the cow was treated by a left-flank laparotomy to correct a uterine torsion that revealed an excessive amount of abdominal fluid and a full term dead fetus. Ultrasonographic evaluation of the right cranioventral thoracic cavity was performed owing to physical examination (muffled heart sounds, areas of silence) and thoracocentesis findings suggestive of pleuritis. Ultrasonography revealed hypoechoic pleural effusion and a mass of mixed echogenicity visible within the right atrial lumen extending into the cranial vena cava. A diagnosis of cranial vena cava thrombosis was demonstrated at necropsy. The clinical, ultrasonographic, and pathological features of this less common condition (cranial vena cava thrombosis) in cattle are discussed.  相似文献   
78.
Echinococcus multilocularis was recently reported in wild canids across southern Ontario, a newly recognized endemic area in Canada. In such areas, a comprehensive understanding of factors associated with infection in definitive hosts (wild canids) is critical for mitigating risk of transmission to humans. However, little is known about the transmission dynamics of the parasite in definitive hosts for this region. A study was therefore carried out to investigate the association of host‐level (sex, body condition), environmental (southern Ontario region, land cover), temporal (season, hunting season, calendar year) and extraneous factors (submitter type) with E. multilocularis infection in coyotes in southern Ontario. Between November 2015 and March 2017, 416 coyotes were collected from across the region as part of a study that investigated the prevalence and distribution of the parasite in wild canids; approximately 24% of coyotes were positive for E. multilocularis. Associations between infection and factors of interest were assessed via a mixed‐effects logistic regression model with a random intercept for submitter to account for clustering. Coyotes with poor body condition were at greater odds of E. multilocularis infection than those in good condition (odds ratio [OR] 2.14; 95% CI: 1.08–4.26; p = .030). A negative association was observed between infection in coyotes and the proportion of natural land in a coyote's estimated home range (OR: 0.67; 95% CI: 0.52–0.85; p = .001). Coyotes from the western region of southern Ontario had lower odds of infection compared to coyotes from the central region (OR: 0.26; 95% CI: 0.12–0.55; p < .001). These results can be used to help guide future public health prevention strategies for human alveolar echinococcosis.  相似文献   
79.
Multiple causes of high extinction risk in large mammal species   总被引:2,自引:0,他引:2  
Many large animal species have a high risk of extinction. This is usually thought to result simply from the way that species traits associated with vulnerability, such as low reproductive rates, scale with body size. In a broad-scale analysis of extinction risk in mammals, we find two additional patterns in the size selectivity of extinction risk. First, impacts of both intrinsic and environmental factors increase sharply above a threshold body mass around 3 kilograms. Second, whereas extinction risk in smaller species is driven by environmental factors, in larger species it is driven by a combination of environmental factors and intrinsic traits. Thus, the disadvantages of large size are greater than generally recognized, and future loss of large mammal biodiversity could be far more rapid than expected.  相似文献   
80.
Major histocompatibility complex (MHC) class I molecules display tens of thousands of peptides on the cell surface, derived from virtually all endogenous proteins, for inspection by cytotoxic T cells (CTLs). We show that, in normal mouse cells, MHC I molecules present a peptide encoded in the 3' "untranslated" region. Despite its rarity, the peptide elicits CTL responses and induces self-tolerance, establishing that immune surveillance extends well beyond conventional polypeptides. Furthermore, translation of this cryptic peptide occurs by a previously unknown mechanism that decodes the CUG initiation codon as leucine rather than the canonical methionine.  相似文献   
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