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51.
Fourteen mature stallions were paired based on age and pretreatment spermatozoal output. One member of each pair was assigned to either 1) control (3 ml corn oil) or 2) treated (132,000 IU retinyl palmitate in 3 ml corn oil) experimental groups. Treatments were added to oat rations every other day. Seminal characteristics (gel free volume, gel volume, total seminal volume, percent progressively motile spermatozoa, number of spermatozoa per ml, percentage morphologically normal spermatozoa and spermatozoal membrane stability) and total scrotal width of each stallion were recorded before (February) and after three months of vitamin A supplementation (June). Plasma vitamin A was measured at 0,6,12,24, and 48 hours following the first and last treatments to document absorption. There were no treatment effects (p>.05) on seminal characteristics or scrotal width. Seasonal increases were recorded in gel-free volume, total seminal volume, percent spermatozoal motility, total spermatozoal output, percentage of morphologically normal spermatozoa, and total scrotal width. Plasma vitamin A was lower during the second collection period (June) than the first (February) in both treatment groups. Peak plasma vitamin A was observed 48 hours following ingestion of the first dose of the vitamin but at 12 hours following the last treatment.  相似文献   
52.
The results of clinical and pulmonary functional evaluation of 24 cats with bronchopulmonary disease and 15 healthy cats are presented. Affected cats had historical evidence of excessive reflexes (coughing, sneezing); physical evidence of airway secretions (crackles), obstruction (wheezing), and increased tracheal sensitivity; radiographic evidence of bronchial and interstitial lung disease; and cytological evidence of airway inflammation or mucous secretions. Bacterial isolates from healthy and affected cats were predominantly Gram-negative rods, indicating that bronchi of cats are not always sterile and that normal flora should be considered in interpreting cultures from cats with suspected bronchopulmonary disease. Cats were grouped according to relative disease severity based on scored historical, physical, and radiographic abnormalities. The mean (± standard deviation) baseline lung resistance measurement in healthy cats was 28.9 cm H2O/L/s (±6.2 cm H2O/L/s), whereas in mildly, moderately, and severely affected cats it was 38.3 cm H2O/L/s (±21.5 cm H2O/L/s), 44.8 cmH2O/L/s (±7.7 cm H2O/L/s), and 105.2 cm H2O/L/s (±66.9 cm H2O/L/s), respectively. In healthy cats, dynamic lung compliance was 19.8 (±7.4), whereas in mildly, moderately, and severely affected cats it was 14.7 mL/cm H2O (±3.8 mL/cm H2O), 17.7 mL/cm H2O (±6.9 mL/cm H2O), and 13.0 mL/cm H2O (±7.9 mL/cm H2O), respectively. Thus, airway obstruction was present in many of the affected cats. Based on acute response to the bron-chodilator, terbutaline, airway obstruction was partially reversible in many affected cats, although the degree of reversibility varied. Furthermore, based on bronchoprovocation testing, 6 (of 7) affected cats evaluated also had increased airway responsiveness to aerosolized methacholine.  相似文献   
53.
54.
An 8-year-old male Labrador retriever presented with a rear limb lameness cased by an osteolytic lesion of the left acetabulum and femoral head and neck. Initial bone biopsy study was nondiagnostic. Histopathologic study and culture of the subsequently excised femoral head and neck revealed a Staphyloccocus intermedial arthritis and osteomyelitis. Neoplash was ruled out on the basis of histopathologic analysis.  相似文献   
55.
Mineral metabolism in the equine is a complex process involving absorption sites and interactions between the minerals themselves and other compounds. Factors such as the digestibility of the minerals and the extent of the interactions all play an important role in the mineral amounts required in the diet.Inadequate levels of minerals in the diet can lead to physiological maladies such as HNS and Ricketts. A knowledge and understanding of mineral metabolism is essential to the success of equine management.  相似文献   
56.
Feline herpesvirus 1 (FHV-1) is one of the most common viral infections of domestic cats worldwide, estimated to cause 50% of all respiratory infections in this species. Feline herpesvirus 1 is also an important ocular pathogen of cats, causing conjunctivitis, epithelial and stromal keratitis, symblepharon formation, keratocon-junctivitis sicca, and corneal sequestration. Despite the importance of this viral disease, major questions remain unanswered concerning the pathogenesis of its most important manifestation, the recrudescent infection. Although the taxonomic classification of FHV-1 as an alpha herpesvirus implies the ability of FHV-1 to establish neural latency, attempts at recovering the virus from the trigeminal ganglia of latently infected cats have typically yielded negative results. This failure has stimulated speculation that neural tissue is not an important site for latent FHV-1. However, in the most successful of such studies, FHV-1 was isolated from the trigeminal ganglia of 3 of 17 cats using an explant technique. In the present study, we describe the successful isolation of FHV-1 from the trigeminal ganglia of cats using a similar tissue culture method.  相似文献   
57.
A standardized investigation was conducted to compare the biophysical properties of hyaluronate products used in the treatment of joint dysfunction in horses. Results showed that two of the five products, Hyvisc® and Hylartin®V, contained higher-weight molecular hyaluronate (greater than 1.5×106). Other investigations have shown that higher molecular weight hyaluronate is effective in providing physical resistance to shear, in stimulating endogenous hyaluronate synthesis, and in inhibiting excess cell proliferation which may be associated with synovial pannus formation. It is suggested that the therapeutic benefits of hyaluronate products may be dependent on the molecular size of the hyaluronate molecules. Higher molecular weight hyaluronate products would be expected to be more effective than lower molecular hyaluronate products in providing therapeutic benefits.  相似文献   
58.
Twenty-four yearlings were used to evaluate the efficacy of feeding feed-grade fat to growing horses. All horses were started on trial at 13-months-of-age and were fed for 112 days. The experimental diets, containing similar nutrient-to-calorie ratios, were: 1) control (no added fat; 2) 5% added fat and; 3) 10% added fat. There was a trend for yearlings fed the 10% added fat diet to grow faster and eat less feed than those on the control diet. Data from this study indicate that feed-grade fat can be safely fed to growing horses. Feeding fat to yearlings stimulated growth and efficiency of feed utilization initially, but these effects were not maintained as the yearlings grew toward maturity.  相似文献   
59.
Ten neonatal calves were anesthetized with xylazine and ketamine intramuscularly and breathed air spontaneously. Drug injection was repeated after 45 minutes. Each injection resulted in a rapid and sustained increase in respiratory rate, but arterial carbon dioxide tension (PaCO2) increased, indicating hypoventilation. Arterial hypoxemia, primarily caused by hypoventilation, developed within 15 minutes of each injection, but gradually disappeared. Acidemia was primarily respiratory in origin. Heart rate and arterial blood pressure decreased for the duration of anesthesia (90 minutes). This form of anesthesia is a satisfactory alternative to inhalation anesthesia of neonatal calves.  相似文献   
60.
OBJECTIVE: To determine whether conscious, unsedated cats will inhale a nebulized material administered via a facemask and whether this material will reach the lower airways. ANIMALS: 20 healthy adult cats. PROCEDURE: Technetium Tc 99m-diaminetriaminopentaacetic acid (99mTc-DTPA) was nebulized into a spacer and administered to the cats via a closely fitting facemask. By use of a gamma camera, images were then immediately obtained to determine the distribution of 99mTc-DTPA within the lower airways. RESULTS: Images obtained by use of the gamma camera revealed that all 20 cats had inhaled 99mTc-DTPA from the facemask. In each cat, deposition of the radiopharmaceutical agent was evident throughout the lung fields. CONCLUSIONS AND CLINICAL RELEVANCE: Awake cats that were not used to the application of a facemask did inhale substances from such a device. Aerosolization of medications may be a feasible route of administration for cats with lower airway disease.  相似文献   
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