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101.
Water vapor-saturated air was delivered to 12 healthy, housed horses for 2 hours daily for 5 days. Treatment had no effect on tracheal mucus transport rate, bronchoalveolar lavage total and differential cell counts, blood cell counts, or plasma fibrinogen concentration.  相似文献   
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103.
A 3-year-old Holstein cow was presented for evaluation of recumbency. Physical examination and laboratory evaluations resulted in a diagnosis of hypokalaemia causing extreme skeletal muscle weakness. Treatment involved intravenous and oral potassium supplementation, antimicrobial and anti-inflammatory therapy, and management of recumbency using a flotation tank (the Aquacow Rise System). The cow recovered and returned to the milking herd. Multifactorial elements were identified as the cause of hypokalaemia including inappetance, treatments for ketosis and administration of dexamethasone.  相似文献   
104.
BACKGROUND: Liver biopsy is useful in the diagnosis of liver disease in horses. However, bleeding is the major complication. Liver dysfunction can result in abnormalities in coagulation, although there is no definitive association between risk of hemorrhage after biopsy and coagulopathy in humans. Frequency of coagulopathies in horses with liver disease and the nature and frequency of complications after liver biopsy are not reported. HYPOTHESIS/OBJECTIVES: To determine whether there is an association between coagulopathy and hemorrhage after liver biopsy in horses. ANIMALS: Horses with suspected liver disease from which a liver biopsy had been obtained. METHODS: Retrospective study. Variables indicative of coagulation were recorded. The frequency and nature of complications after biopsy were assessed using clinical and hematologic data. The association between abnormal coagulation variables and complications was assessed. RESULTS: Seventy biopsies were obtained from 66 horses. At least 1 coagulation profile abnormality was identified in 58% of the 43 horses with histopathologically confirmed liver disease. Complications were observed in 4/32 monitored horses (33 biopsies). Three horses had a decrease in the packed cell volume suggestive of subclinical bleeding, and 1 horse developed a diaphragmatic hematoma. There was no association between coagulation profile abnormality and complications. CONCLUSION AND CLINICAL IMPORTANCE: Abnormalities of coagulation are common in horses with liver disease. Liver biopsy appears to be a safe procedure in the horse. An abnormal coagulation profile is not clearly associated with an increased risk of complications after biopsy.  相似文献   
105.
Eastern Gamagrass [ Tripsacum dactyloides (L.) L.] is a perennial C4 grass with potentially high productivity. Intensive management through the application of nitrogen (N) fertilizer and frequency of cutting, however, may be required to maximize its potential for forage production. This study determined the long-term and residual responses of Eastern Gamagrass in terms of dry matter (DM) yield and tiller density to three annual application rates (0, 50 or 100 kg ha−1) of a N-fertilizer solution applied by broadcasting or knife placement for 5 out of the 10 years of the study, and harvested using one-cut or two-cut regimes. Application of N-fertilizer increased total DM yield in the 5 years of N applications by 0·44 with the first increment of 50 kg N ha−1, and by an additional 0·15 with the next increment of 50 kg N ha−1. In the first year that directly followed N-fertilizer applications, DM yield was 0·175 higher than the no fertilizer treatment when 50 kg ha−1 had been previously applied and a further 0·16 higher when 100 kg ha−1 had been previously applied. Dry matter yields were greater from the one-cut than the two-cut regime only in years when no N-fertilizer was applied. Knife placement of N-fertilizer increased total DM yield only at 100 kg N ha−1. Tiller densities were generally higher under the one-cut than the two-cut regime, particularly when N-fertilizer was broadcast. The application of N-fertilizer increased herbage production, especially when responses in the year subsequent to application are considered.  相似文献   
106.
Verotoxigenic E. coli (VTEC) belong to a diverse range of serotypes. Serotypes O157 and O26 are predominately identified in VTEC-associated disease in Europe, however due to difficulty in detection little is known about the epidemiology of non-O157 serotypes. This study reports the identification of 7 VTEC serotypes from cattle faeces and soil. Cattle faeces samples (n=128) were taken from animals in 6 different farms, with soil samples (n=20) obtained from 1 farm. After sample incubation in modified tryptone soy broth (mTSB) supplemented with streptomycin sulphate samples were plated onto sorbitol MacConkey (SMAC) also supplemented with streptomycin sulphate. Bacteria detected on the plates were subjected to biochemical testing, antibiotic resistance profiling, and PCR to detect typical virulence genes, beta-lactamase and class 1 integron associated genes. Serotyping was performed on isolates positive for virulence genes. E. coli was identified from 103 samples, with verotoxin genes present in 7 E. coli isolates. Of these 7 isolates, 5 were resistant to 5 or more antibiotics. The isolate resistant to 9 antimicrobials contained a class 1 integron structure. Serotyping identified 7 separate VTEC, O2:H27, O26:H11, O63:H(-), O148:H8, O149:H1, O174:H21 and ONT:H25. Six of these VTEC have been previously associated with human disease, however with the exception of O26:H11, these serotypes have been rarely reported worldwide. Increased surveillance is required to determine the prevalence of these and other non-O157 VTEC. The presence of multi-antibiotic resistance in these isolates is of concern, and the overall implications for public health must be ascertained.  相似文献   
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108.
Hypertrophic osteodystrophy (HOD) is a canine bone disease that affects mainly large breed dogs, including the Weimaraner, and studies have shown a link between recent vaccination with a modified live virus and the onset of HOD in this breed. In humans, it has been suggested that human leukocyte antigen (HLA) alleles can influence antibody response to vaccination. The aim of this study was to investigate whether there is an association between the development of HOD in Weimaraners and MHC alleles at the DLA-DQA1 locus in a group of 33 unrelated dogs. The DQA1 allele and genotype frequencies were determined by sequence-based typing. Although clinical signs developed within six weeks of vaccination in all 12 dogs for which information was available, no association was found between DQA1 alleles and HOD in this population of Weimaraner dogs. A role for other immune-response genes in the pathogenesis of HOD should not however be ruled out. Whereas recent vaccination may be a trigger for the disease, it was concluded that there is no specific vaccine that is most responsible for the expression of the disease.  相似文献   
109.
It is essential to isolate high-quality DNA from muscle tissue for PCR-based applications in traceability of animal origin. We wished to examine the impact of cooking meat to a range of core temperatures on the quality and quantity of subsequently isolated genomic (specifically, nuclear) DNA. Triplicate steak samples were cooked in a water bath (100 degrees C) until their final internal temperature was 75, 80, 85, 90, 95, or 100 degrees C, and DNA was extracted. Deoxyribonucleic acid quantity was significantly reduced in cooked meat samples compared with raw (6.5 vs. 56.6 ng/microL; P < 0.001), but there was no relationship with cooking temperature. Quality (A(260)/A(280), i.e., absorbance at 260 and 280 nm) was also affected by cooking (P < 0.001). For all 3 genes, large PCR amplicons (product size >800 bp) were observed only when using DNA from raw meat and steak cooked to lower core temperatures. Small amplicons (<200 bp) were present for all core temperatures. Cooking meat to high temperatures thus resulted in a reduced overall yield and probable fragmentation of DNA to sizes less than 800 bp. Although nuclear DNA is preferable to mitochondrial DNA for food authentication, it is less abundant, and results suggest that analyses should be designed to use small amplicon sizes for meat cooked to high core temperatures.  相似文献   
110.
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