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1.
Burns JJ MacMillan K Uehlinger FD Riley CB 《The Canadian veterinary journal. La revue veterinaire canadienne》2011,52(3):295-296
A stallion presenting for surgical correction of an acquired inguinal hernia was also diagnosed with a nephrosplenic entrapment (NSE) intraoperatively. Surgical intervention resulted in a successful outcome. To date, these conditions have not been reported to occur simultaneously. 相似文献
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The objective of this research was to examine the effect of high concentrations of nonprotein nitrogen (NPN) on the voluntary food intake of sheep fed high-quality grasses. Wether lambs (n = 6 per treatment) were fed dried switchgrass (Panicum virgatum L.; Exp. 1) or dried tall fescue (Festuca arundinacea Schreb.; Exp. 2). In both experiments, urea was added to the dried forage at 0 (control), 12, or 24 g of N/kg of DM to increase the NPN concentration. Acid detergent fiber concentrations were 305 g/kg of DM in both experiments, although DM digestibility was 663 and 618 g/ kg of DM in Exp. 1 and Exp. 2, respectively. Voluntary feed intake of the control forage was 28.2 and 19.1 g/ kg of BW in Exp. 1 and Exp. 2, respectively, and decreased for the high-urea treatments to 25.2 and 16.2 g/kg of BW in Exp. 1 (P = 0.07) and Exp 2 (P = 0.03), respectively. Total feed N concentrations increased from 29.5 g to 45.7 g of N/kg of DM in Exp. 1 (P < 0.01) and from 28.4 to 55.9 g of N/kg of DM in Exp. 2 (P < 0.01). Nonprotein N concentrations increased from 28.3 to 53.8% of the total N in switchgrass diets (Exp. 1; P < 0.01), and from 26.4 to 64.0% in tall fescue diets (Exp. 2; P < 0.01). Plasma urea concentrations of the lambs increased from 3.1 to 6.6 mM (Exp. 1; P < 0.01) and from 2.9 to 5.8 mM (Exp. 2; P < 0.01) as the amount of urea added to the diets increased. These changes resulted in an increase in plasma osmolality from 298 to 307 mOsm/kg (Exp. 1; P = 0.04), and from 299 to 307 mOsm/kg (Exp. 2; P = 0.06). Increasing feed N and NPN concentrations through the addition of urea caused a significant decrease in the voluntary feed intake of sheep fed tall fescue and switchgrass. These responses showed no significant cause-and-effect relationship between voluntary feed intake, plasma urea concentrations, and plasma osmolality. 相似文献
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Ultrastructural study of the liver and kidney in ochratoxicosis A in young broiler chicks 总被引:1,自引:0,他引:1
Ultrastructural changes are reported in the kidney and liver of 20-day-old broiler chicks fed ochratoxin A (OA), incorporated in the diet at levels of 2 and 4 ppm. Changes in the kidney included the presence of abnormally shaped mitochondria in the proximal convoluted tubules. There was an increase in the size and number of mitochondrial dense granules and cytoplasmic peroxisomes. Intranuclear and cytoplasmic lipid droplets and electron dense round bodies in the dilated smooth endoplasmic reticulum were also noted. Regional thickening and degeneration of the glomerular basement membrane was observed in some cases. In the liver from OA fed birds there was an increased accumulation of cytoplasmic glycogen in the hepatocytes. Abnormal mitochondrial ring forms in the kidney and the accumulation of glycogen in the liver are considered to be of diagnostic significance in ochratoxicosis of young broiler chicks. The severity of the changes was found to be dose related. These results suggest that the mitochondria in the proximal convoluted tubules of kidney were most sensitive to OA toxicity. 相似文献
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Grazing ruminants use both visual cues and taste in selecting their diet. Preference during grazing may not be the same when forage is dried for hay and cut into lengths prior to feeding in confinement. Eight cultivars of tall fescue (Festuca arundinacea Schreb.), previously evaluated for preference while grazed, were harvested three times over a period of 2 yr. The hays were air-dried, baled, and passed through a hydraulic bale processor prior to feeding. Five experiments were conducted. All three harvests were evaluated with sheep and the last two also with goats, using six animals each time. During an adaptation phase, hays were offered alone as meals. In the experimental phase, every possible pair of hays (28 pairs) was presented for a meal. Data were analyzed by multidimensional scaling and by traditional analyses. Preference was significant among cultivars in all experiments. Multidimensional scaling showed that selection was based on two criteria with two dimensions being significant. Sheep preferred KENHY followed by KENTUCKY 31 and STARGRAZER but preferenced against BARCEL. HIMAG, MO-96, and C1 were intermediate and MOZARK was variable. Goats were similar to sheep in preferring KENHY followed by STARGRAZER and selected against MOZARK and BARCEL. KENTUCKY 31, HIMAG, MO-96, and C1 were intermediate. In all five experiments, the general association was positive for available carbohydrate fractions and negative for fiber fractions that contribute to cell wall rigidity. 相似文献