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21.
A 9-year-old Bullmastiff with hematemesis was determined to have primary neuroendocrine carcinoma of the gallbladder. Despite the dismal prognosis when these unusual tumors are located in the liver, the hematemesis resolved, and there was no obvious tumor regrowth in this dog 10 months after cholecystectomy.  相似文献   
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23.
Manure is a source of plant nutrients and can make a valuable contribution to soil organic matter (SOM). Two experimental sites were studied on a Halpic Phaeozem soil near Bad Lauchstadt in Germany. The first experiment, called the static experiment, commenced in 1902. The impact of fresh farmyard manure (FYM) (0, 20 and 30 t ha−1 2 year−1) combined with P, K and N fertiliser application on total organic C (CT), labile C (CL), non-labile C (CNL), total N (NT), mean weight diameter (MWD) and unsaturated hydraulic conductivity (Kunsat) was investigated. The second experiment commenced in 1984 and investigated the effect of extreme rates of fresh FYM applications (0, 50, 100 and 200 t ha−1 year−1) and cropping, or a continuous tilled fallow on the same soil properties. At both sites a nearby grassland site served as a reference. On the static experiment, FYM application increased all C fractions, particularly CL, where application of 30 t ha−1 2 year−1 increased CL by 70% compared with no FYM application. Fertiliser additions to the static experiment had a positive influence on C fractions while NT increased from both FYM and fertiliser application. MWD increased as a result of FYM application, but did not reach that of the grassland site. Both fertiliser and FYM application increased Kunsat (10 mm tension) on the static experiment. In the second experiment application of 200 t ha−1 year−1 of FYM increased concentrations of CL by 173% and of CNL by 80%, compared with no FYM application to make them equivalent to, or greater than the grassland site. A continuously tilled fallow resulted in significant decreases in all C fractions, NT and MWD compared with the cropped site, while Kunsat (10 mm tension) was increased on the 0 and 50 t ha−1 year−1 treatments as a result of a recent tillage. There was no difference in Kunsat between the cropped and the continuous tilled fallow at FYM applications of 100 and 200 t ha−1 year−1. There were similar significant positive correlations of all C fractions and NT with MWD on both experimental sites but the relationships were much stronger on the extreme FYM experiment. Weaker relationships of C fractions and NT with Kunsat (10 mm tension) occurred for the static experimental site but these were not significant for the extreme FYM experimental site. The strongest relationship between C fractions and Kunsat was with CL. This research has shown that applications of FYM can increase SOM and improve soil physical fertility. However, the potential risk of very high rates of FYM on the environment need to be taken into consideration, especially since the application of organic materials to soils is likely to increase in the future.  相似文献   
24.
A synthetic juvenile hormone mimic has been shown to cause premature metamorphosis of the cyprid larva of an acorn barnacle in concentrations as low as 10 parts per billion in filtered seawater. The effect of a juvenile hormone mimic on a crustacean has not previously been demonstrated.  相似文献   
25.
Total parenteral nutrition in clinically normal cats   总被引:2,自引:0,他引:2  
Seven clinically normal cats were maintained on total parenteral nutrition (TPN) with nothing given PO for 2 weeks. The TPN solution consisted of a mixture of dextrose, amino acids, soybean oil emulsion, electrolytes, and vitamins. Three cats were fed calories in excess of published maintenance requirements, and they gained some weight, vomited occasionally, had oral ulcerations, and had signs of depression after 10 to 13 days on TPN. Four cats that were not overfed did well clinically and maintained stable body weights. All cats developed anemia and thrombocytopenia to varying degrees during TPN administration and had polyuria and serum triglyceride concentrations higher than normal fasting values. Some cats had changes in liver-specific biochemical variables. Hepatocellular swelling and vacuolation and small intestinal villous atrophy and fusion were the most common histopathologic changes seen after TPN. These changes were reversible when TPN was discontinued and the cats were returned to enteral nutrition.  相似文献   
26.
Twelve 3/4 Angus (Angus) and 12 Wagyu-cross (1/2 Wagyu x 1/2 Angus) (Wagyu) heifers were weaned at 180 d of age and grazed on endophyte-infected tall fescue for 16 mo before entering the feedlot as 2-yr-olds. Twelve 3/4 Angus heifer calves and 12 Wagyu-cross heifer calves from the following year's calf crop were weaned at 142 +/- 4.1 d of age, immediately adjusted to an 80% concentrate diet, and finished as calves. All heifers were fed a common finishing diet until an estimated 50% of their respective group would grade USDA low Prime or better based on ultrasound predictions. Ultrasound measurements of s.c. and i.m. fat depots were recorded at 60-d intervals throughout the finishing period. Heifers finished as calves had higher (P = 0.02) marbling scores at any given fat thickness and gained more efficiently (P < or = 0.01) at any given marbling score than heifers finished as 2-yr-olds. Gain:feed decreased quadratically (P < or = 0.05) as 12th-rib fat thickness increased for Angus and Wagyu heifers. Gain:feed decreased linearly (P < or = 0.01) for Wagyu calves and quadratically (P < or = 0.01) for Angus calves as 12th-rib fat thickness increased. However, these differences in slope were not different (P = 0.34) as a result of breed among heifers finished as calves. Marbling score increased linearly (P < or = 0.01) as 12th-rib fat thickness increased for Angus and Wagyu heifers finished as 2-yrolds or as calves. However, Wagyu heifers, regardless of age at feedlot entry, had a higher marbling score (P < or = 0.05) at any given 12th-rib fat thickness than Angus heifers. Finishing early-weaned heifers as calves as opposed to 2-yr-olds results in i.m. fat deposition during a period of more efficient growth. Additionally, including Wagyu genetics into the breeding of early-weaned heifers finished as calves or as 2-yr-olds results in higher marbling scores at any 12th-rib fat thickness.  相似文献   
27.
The effect of peak lactation on the activities of a number of enzymes of glucose and lipid metabolism of perirenal and subcutaneous adipose tissue, skeletal muscle, liver, kidney cortex and mammary parenchyma of sheep are described. Enzymes studied included hexokinase (glucose utilization), pyruvate carboxylase (gluconeogenesis), pyruvate dehydrogenase (glucose oxidation and production of acetyl CoA for fatty acid synthesis), acetyl CoA carboxylase (fatty acid synthesis) and glycerol-3-phosphate acyltransferase (fatty acid esterification). Major changes that were found include a decrease in activities of enzymes of fatty acid synthesis and esterification in adipose tissues, decreased activity of pyruvate dehydrogenase in muscle and adipose tissues and increased pyruvate carboxylase; there was no change in activities of enzyme of fatty acid esterification in liver. Activities of hexokinase, acetyl CoA carboxylase and glycerol-3-phosphate acyltransferase have been estimated per tissue; this shows the quantitative importance of limiting glucose utilization by muscle and of suppression of fatty acid synthesis in adipose tissue for efficient partitioning of nutrients for milk production.  相似文献   
28.
The effects of different levels of cracked corn on N intake, ruminal bacterial CP synthesis, and duodenal flows and small intestinal digestion of amino acids (AA) in steers fed fresh alfalfa indoors were determined. Angus steers (n = 6; average BW 338 +/- 19 kg) cannulated in the rumen, duodenum, and ileum were fed each of five diets over five periods in a Latin square design with an extra animal. Steers consumed 1) alfalfa (20.4% CP, 41.6% NDF) ad libitum (AALF); 2), 3), and 4) AALF supplemented (S) with three levels of corn (.4, .8, or 1.2% of BW, respectively), or 5) alfalfa restricted (RALF) to the average forage intake of S steers. Average N intake and duodenal flow of nonammonia N (NAN) were greater (P < .01) in S than in RALF steers. Greater duodenal flows of NAN in S compared with RALF were due to a trend toward higher (P = .06) flows of both bacterial and dietary N. Levels of corn decreased (P < .01) linearly N intake and increased (P < .01) linearly duodenal flow of NAN owing to a numerical linear increase in nonbacterial N (P = .15) with no increase in bacterial N flow. Duodenal NAN flows as percentages of N intake increased (P < .01) linearly (69.3 to 91.0%) as corn increased. Ruminal NH3 N concentration, ruminal CP degradability, and the proportion of bacterial N in duodenal NAN were decreased (P < .01) linearly as corn increased. Efficiency of net microbial CP synthesis was not affected (P > .05) by treatment (average 42.6 and 30.9 g N/kg of OM apparently or truly digested in the rumen, respectively). Small intestinal disappearance of total N and individual AA, except for threonine and lysine, and small intestinal digestibility of N and individual AA, except for methionine, histidine, and proline, increased (P < .01) linearly with level of corn and were greater (P < .01) in S than in RALF steers. Supplementing corn to steers fed fresh alfalfa reduced ruminal N losses and CP degradability and increased the duodenal flow and the small intestinal disappearance and digestibility of total N and total, essential, and nonessential AA.  相似文献   
29.
Seventy-three crossbred steers (initial BW = 170.5 +/- 5.5 kg) from The Ohio State University (Exp. 1) and 216 crossbred steers (initial BW 135.4 +/- 4.4 kg) from the University of Illinois (Exp. 2) were used to determine the effect of source of energy and rate of growth on performance, carcass characteristics, and glucose and insulin profiles on early-weaned steers. Effects of the diets used in Exp. 1 and 2 on ruminal pH and VFA concentrations were quantified using ruminally fistulated steers (Exp. 3). Cattle were weaned at an average age of 119 d in all experiments and were allotted by age, BW, and breed to one of four diets: high-concentrate, fed ad libitum (ALCONC), high-concentrate fed to achieve a gain of either 1.2 kg/d (1.2CONC) or 0.8 kg/d (0.8CONC), or high-fiber, fed ad libitum (ALFIBER). At 218 d of age, all steers were placed on the ALCONC diet until slaughter. Steers were implanted with Compudose at the initiation of all experiments and with Revalor-S when they were estimated to be 100 d from slaughter. When steers in Exp. 1 averaged 181 and 279 d of age, serum samples were collected to determine glucose and insulin concentrations. Steers were slaughtered when a fat thickness of 1.27 cm was reached (Exp. 1) or after 273 d on feed (Exp. 2). In Exp. 1, days in the feedlot (P < 0.01) and age at slaughter (P < 0.01) were lowest for ALCONC and ALFIBER steers, and greatest for 0.8CONC steers. Overall, ADG was greatest for ALCONC and lowest for 0.8CONC steers; feed efficiency was lowest (P < 0.01) for ALFIBER steers. Final BW did not differ (P > 0.57) among treatments. At 181 and 218 d of age, serum insulin was increased (P < 0.10) and intramuscular fat percentage was greatest (P < 0.07), respectively, for ALCONC steers. In Exp. 2, overall ADG (P < 0.06) and final BW (P < 0.04) were greatest for ALCONC and lowest for 1.2CONC and 0.8CONC steers. Overall feed efficiency was greatest for 0.8CONC and lowest for ALFIBER (P < 0.01). Growing phase diet did not affect marbling score at 218 d of age or at slaughter (P > 0.81). In Exp. 3, differences in ruminal pH after feeding may have been a consequence of increasing acetate (ALFIBER), propionate (ALCONC), or a combination of VFA (0.8CONC and 1.2CONC), respectively (diet x time after feeding, P < 0.10). Controlling growth by limit-feeding a high-concentrate diet for only 100 d does not extend the growth curve of early-weaned steers or enhance intramuscular fat deposition at slaughter compared to ad libitum intake of a high-concentrate or high-fiber diet.  相似文献   
30.
Two experiments were conducted in which pregnant crossbred cows were randomly assigned to a control group or implanted with testosterone propionate/silastic implants between d 110 and 140 of gestation in Exp. 1 and between d 80 and 110 of gestation in Exp. 2. Androgenized heifers (TH) and treated steers (TS), born to implanted dams, possessed similar birth weights compared with control heifers (CH) and steers (CS), respectively, in both experiments. In Exp. 1, yield grades were lower (P less than .05) for TH than for CH. In Exp. 2, TH possessed 9.4% greater (P less than .07) 205-d adjusted weaning weights and 9.8% heavier (P less than .05) adjusted yearling weights than CH. In Exp. 2, daily gain was 19.5% faster (P less than .05) and feed intake was 13.6% greater (P less than .05) for TH than for CH. In Exp. 2, TH possessed less (P less than .05) s.c. fat, greater (P less than .10) carcass weight gains and lower (P less than .05) yield grades than CH. Liver weight per unit of carcass weight was greater (P less than .07) for TH than for CH in Exp. 2. Androgenized heifers had lower (P less than .07) lipid content in the 9-10-11th rib section than did CH. Calving intervals were similar for implanted and nonimplanted cows in both experiments. Results from these two trials suggest that efficiency of heifers for producing carcass beef can be improved by prenatal testosterone exposure.  相似文献   
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