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991.
992.
993.
Urethral obstruction in a male llama   总被引:1,自引:0,他引:1  
An 8-year-old sexually intact male llama was euthanatized because of obstruction of the penile portion of the urethra and rupture of the urinary bladder. Clinical signs of obstruction included anorexia, lethargy, teeth grinding, straining to defecate, inability to urinate, and tense abdomen. Laboratory findings included anemia, leukocytosis with left shift, high serum urea nitrogen, creatinine, and phosphorus concentrations, and low serum chloride concentration. Necropsy revealed ruptured urinary bladder and acute fibrinous peritonitis. A firm, gray, nonmineralized urethral plug occluded the penile portion of the urethra for a distance of 14 cm in the midpenile region, distal to the sigmoid flexure of the penis. The urinary bladder mucosa and the urethra had microscopic evidence of chronic inflammation. Escherichia coli, Klebsiella sp, and alpha-streptococci were isolated from the urethral plug.  相似文献   
994.
The effects of ionophores on liver weight and function were determined in finishing steers (n = 24; avg weight 440 kg). Steers were group-fed one of three treatments (control, lasalocid or monensin at 33 mg/kg feed) for 46 d prior to slaughter. Three days prior to slaughter, blood was collected for the determination of serum Ca and Mg. At slaughter, the liver was removed, weighed, sampled, frozen in liquid nitrogen and subsequently analyzed for concentrations of carbohydrate metabolites and minerals. Liver weight (5.9 kg) was unaffected by treatment. Serum and hepatic Ca and Mg were not affected by ionophore treatment. Hepatic glycogen levels in steers fed ionophores were unaffected by treatment. Fructose 1,6-bisphosphate was 21% lower (P less than .10) in hepatic tissue of steers fed ionophores, whereas dihydroxyacetone phosphate was 15 to 37% greater in hepatic tissue of steers fed monensin (P less than .20) or lasalocid (P less than .10). Glyceraldehyde 3-phosphate was elevated more extensively by lasalocid than by monensin with increases of 72 (P less than .05) and 132% (P less than .001), respectively, over controls. Glycerol 3-phosphate levels were 37% (P less than .05) and 12% (NS) greater with these ionophores. Hepatic levels of pyruvate were elevated 12 (NS) to 36% (P less than .17) for monensin and lasalocid. Fructose 2,6-bisphosphate levels were 25% lower (P less than .25) in hepatic tissue of steers fed ionophores than in hepatic tissue from control steers. Other metabolites of carbohydrate metabolism in hepatic tissue were not altered appreciably. Changes in levels of intermediary metabolites of carbohydrate metabolism suggest alterations in hepatic carbohydrate metabolism favoring gluconeogenesis in steers fed ionophores.  相似文献   
995.
Pituitary adenylate cyclase‐activating polypeptide (PACAP) is a neuropeptide with diverse biological actions. Type I PACAP receptors (PACAPR) are specific for PACAP, whereas type II and III PACAPRs are less restricted. To localize and analyse the variation of this gene, a 559‐bp long intronic fragment of the porcine PACAPR gene was amplified by polymerase chain reaction and sequenced in samples from five different pig breeds. One single nucleotide polymorphism was identified and its allele frequency was determined in all five breeds. Linkage analysis in a Berkshire × Yorkshire reference family placed the PACAPR gene on chromosome 18, between SW787 and S0062 (SW787– 8.1 cM –PACAPR– 3.0 cM –S0062). Radiation hybrid mapping confirmed that the PACAPR gene was linked to SW1682 on chromosome 18 (28.8 cR3000; LOD = 10.4).  相似文献   
996.
This study was conducted to evaluate the accuracy of the National Research Council's (2000) Nutrient Requirements of Beef Cattle computer model when used to predict calf performance during on-farm pasture or dry-lot weaning and backgrounding. Calf performance was measured on 22 farms in 2002 and 8 farms in 2003 that participated in West Virginia Beef Quality Assurance Sale marketing pools. Calves were weaned on pasture (25 farms) or dry-lot (5 farms) and fed supplemental hay, haylage, ground shell corn, soybean hulls, or a commercial concentrate. Concentrates were fed at a rate of 0.0 to 1.5% of BW. The National Research Council (2000) model was used to predict ADG of each group of calves observed on each farm. The model error was measured by calculating residuals (the difference between predicted ADG minus observed ADG). Predicted animal performance was determined using level 1 of the model. Results show that, when using normal on-farm pasture sampling and forage analysis methods, the model error for ADG is high and did not accurately predict the performance of steers or heifers fed high-forage pasture-based diets; the predicted ADG was lower (P < 0.05) than the observed ADG. The estimated intake of low-producing animals was similar to the expected DMI, but for the greater-producing animals it was not. The NRC (2000) beef model may more accurately predict on-farm animal performance in pastured situations if feed analysis values reflect the energy value of the feed, account for selective grazing, and relate empty BW and shrunk BW to NDF.  相似文献   
997.
Twenty dogs and 29 cats were identified with urethral rupture. Males predominated in both groups. The most common cause of urethral rupture in dogs was vehicular trauma, and in cats it was trauma associated with urethral obstruction and catheterization. Clinicopathological findings, type of surgical correction, time to surgery, type of urinary diversion, and duration of urinary diversion were not statistically associated with the outcome. In this study, the presence of multiple traumatic injuries was associated with a poor outcome.  相似文献   
998.
Liver microsomes from market-size ( n  = 6) rainbow trout, channel catfish and tilapia were used to investigate in vitro biotransformation kinetics of albendazole (ABZ). ABZ was transformed to a single metabolite, ABZ sulfoxide (ABZ-SO). Catfish displayed the highest maximal velocity ( V max = 264.0 ± 58.6 pmols ABZ-SO/min/mg protein) followed by tilapia (112.3 ± 8.2) and rainbow trout (73.3 ± 10.3). V max in catfish was significantly different ( P  < 0.05) from the other two species. Michaelis–Menten constant ( K m) values (μ m ) varied significantly among the species: rainbow trout (3.9 ± 0.5), tilapia (9.2 ± 1.7) and catfish (22.0 ± 3.2). However, V max/ K m ratios showed no difference among the three species, making them equally efficient performing this phase I biotransformation reaction. In a second series of experiments, channel catfish ( n  = 6 per treatment) were dosed in vivo with gel-food containing ABZ (10 mg/kg, p.o.). Fish were killed at 24, 48, 72 and 120 h after dosage. Control fish were fed ABZ-free feed. Induction of ethoxyresorufin-o-deethylase activity was significant ( P  < 0.05) in all ABZ-dosed treatments as compared with controls.  相似文献   
999.
Background: Various protocols using different doses of recombinant human thyrotropin (rhTSH) in TSH stimulation testing have been described. However, the influence of TSH dosage on thyroxine (T4) concentration has not yet been evaluated in suspected hypothyroid dogs.
Objective: To evaluate the effectiveness of 2 doses of rhTSH.
Animals: Fifteen dogs with clinical signs consistent with hypothyroidism and abnormal stimulation results with 75 μg rhTSH and 18 clinically healthy dogs.
Methods: All dogs were stimulated with 75 and 150 μg rhTSH IV in a 1st and 2nd stimulation test, respectively. Blood samples were taken before and 6 hours after rhTSH administration for determination of total T4 concentration.
Results: Using the higher dose led to a normal test interpretation in 9 of the 15 dogs, in which stimulation had been abnormal using the lower dose. Based on follow-up information, hypothyroidism was excluded in 7 of these 9 dogs. In all 6 dogs with a blunted response to the higher dose, hypothyroidism could be confirmed. Healthy dogs showed significantly higher post-TSH T4 concentrations with the higher compared with the lower dose. Post-TSH T4 concentrations after TSH stimulation were not related to dogs' body weight in either healthy or diseased dogs.
Conclusions and Clinical Relevance: TSH dose significantly influenced test interpretation in suspected hypothyroid dogs. Differentiation between primary hypothyroidism and nonthyroidal disease was improved with 150 μg rhTSH. Because this effect was independent of the dogs' body weight, the higher dose is recommended in dogs that have concurrent disease or are receiving medication.  相似文献   
1000.
Net portal absorption of AA during the 6-h postprandial period was measured in eight gilts (48.5 +/- 1.6 kg BW) in a crossover design. The pigs had chronic catheters placed in the portal vein, carotid artery, and ileal vein, and were trained to consume 1.2 kg of a standard grower diet once daily. Blood samples were taken every 30 min for 4 h and then hourly until 6 h after feeding. The first set of blood samples was taken after pigs were fed a meal of the test 16% CP corn-soybean meal diet (16% CP) or the test 12% CP corn-soybean meal diet supplemented with crystalline lysine, threonine, and tryptophan (12% CP + AA) to equal the three AA levels in the 16% CP diet. Pigs were then fed the standard diet for 2 d. Following that, blood samples were again taken after the pigs were fed a meal of the test diet that was not given to them at the first sampling period. Net portal AA absorption was calculated by multiplying porto-arterial plasma AA concentration difference by portal vein plasma flow rate (PVPF), estimated by an indicator-dilution technique employing p-aminohippuric acid as the indicator infused into the ileal vein. Plasma concentrations of lysine and threonine of pigs were affected by the diet x time interaction (P < 0.01). Portal and arterial plasma lysine and threonine concentrations in pigs attained the maximal level by 1 h postprandial when the 12% CP + AA diet was fed, but reached the peak level at 2.5 h postprandial when the 16% CP diet was given. The PVPF of pigs over the 6 h postprandial was less (P < 0.01) when the 12% CP + AA diet was given than when the 16% CP diet was fed. Net portal absorptions of lysine and threonine also were affected (P < 0.05) by time x diet interaction. The peak portal absorption of both lysine and threonine in pigs appeared at 0.5 h postprandial when the 12% CP + AA diet was given, but at 2.5 h postprandial with the feeding of the 16% CP diet. The early appearance of peak portal absorption of lysine and threonine from feeding the 12% CP + AA compared with the 16% CP diet indicates that crystalline lysine and threonine are absorbed more rapidly than protein-bound lysine and threonine in pigs fed once daily.  相似文献   
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