COMPARISON OF MAGNETIC RESONANCE IMAGING AND MYELOGRAPHY IN 18 DOBERMAN PINSCHER DOGS WITH CERVICAL SPONDYLOMYELOPATHY

Eighteen Doberman pinscher dogs with clinical signs of cervical spondylomyelopathy (wobbler syndrome) underwent cervical myelography and magnetic resonance (MR) imaging. Cervical myelography was performed using iohexol, followed by lateral and ventrodorsal radiographs. Traction myelography was performed using a cervical harness exerting 9 kg of linear traction. MR imaging was performed in sagittal, transverse, and dorsal planes using a 1.5 T magnet with the spine in neutral and traction positions. Three reviewers independently evaluated the myelographic and MR images to determine the most extensive lesion and whether the lesion was static or dynamic. All reviewers agreed with the location of the most extensive lesion on MR images (100%), while the agreement using myelography was 83%. The myelogram and MR imaging findings agreed in the identification of the affected site in 13-16 dogs depending on the reviewer. MR imaging provided additional information on lesion location because it allowed direct examination of the spinal cord diameter and parenchyma. Spinal cord signal changes were seen in 10 dogs. Depending on the reviewer, two to four dogs had their lesions classified as dynamic on myelography but static on MR images. Myelography markedly underscored the severity of the spinal cord compression in two dogs, and failed to identify the cause of the signs in another. The results of this study indicated that, although myelography can identify the location of the lesion in most patients, MR imaging appears to be more accurate in predicting the site, severity, and nature of the spinal cord compression.     

Cu2+对中华倒刺鲃超氧化物歧化酶活性的影响

Cu2+是养殖水体的常见污染物,为了评估Cu2+对鱼类超氧化物歧化酶(SOD)的影响,将中华倒刺鲃暴露于含0.01～0.32 mg/L Cu2+的水体中饲养8 d,测定肌肉、血浆及肝脏中SOD活性的变化.实验结果显示,低浓度Cu2+(0.01 mg/L)对肌肉、血浆及肝脏的SOD有诱导作用,随着处理时间的延长而升高.但当浓度较高(0.04mg/L以上)时,SOD活性均呈现先诱导后抑制的趋势.Cu2+浓度越高,SOD活性上升越急剧,出现活性抑制的时间就越提前.此外,SOD在3种组织中的分布亦存在明显差异,肝脏的SOD活性最大.这些结果表明,肝脏SOD活性更宜作为Cu2+污染的生物标记.     

Energy balance for ethyl alcohol production from crops

Energy requirements to produce ethyl alcohol from three different crops in Brazil (sugarcane, cassava, and sweet sorghum) were calculated. Figures are presented for the agricultural and industrial phases. The industrial phase is always more energy-intensive, consuming from 60 to 75 percent of the total energy. Sugarcane is the more efficient crop for ethyl alcohol production, followed by sweet sorghum and cassava from a net energy viewpoint. The utilization of sweet sorghum stems might increase the total energy gain from this crop to almost the same level as sugarcane. Cassava has a lower energy gain at the present state of agriculture in Brazil.     

西藏核桃休眠及萌芽特性研究

利用浓硫酸浸泡处理西藏核桃种子,通过种子吸水率、不同层积方法和内源抑制物对小白菜萌发影响试验等方面来研究西藏核桃的休眠及萌芽特性.结果表明:用浓硫酸处理种吸水率大于对照,种壳并不是引起休眠的主要原因,外壳、内种皮、种仁可能均含有抑制种子发芽物质.用浓硫酸浸泡90 min,变温层积萌动时间早,且萌动率高;低温层积160 d,再在22℃恒温条件下发芽率高,为68%.     

Alkaline hydrolyzable nitrogen and properties that dictate its distribution in paddy soil profiles

Nitrogen (N) is a key nutrient for rice production, and its bioavailability in paddy soils is strongly coupled to soil organic matter (SOM) cycling. A better understanding of potentially available N forms in soil, such as alkaline hydrolyzable N (AH-N), and their depth distribution will support the development of best management practices to improve the N use efficiency of rice while minimizing adverse environmental effects. Fifteen rice (Oryza sativa L.) fields from Southern Brazil were selected, and stratified soil samples were taken to a depth of 60 cm before crop establishment. Selected soil physical and chemical properties were analyzed to evaluate their relationships with AH-N contents in the soil profile. The AH-N contents below 20 cm varied extensively (increased, reduced, or constant) compared with that above 20 cm. Although clay and clay + silt contents were highly correlated to AH-N for some soils, the major property dictating AH-N distribution by depth was total N (TN), as the correlation between TN and AH-N was mainly by direct effect. The proportion of TN recovered as AH-N across sites and depths presented high amplitude, and thus AH-N was not a constant N pool across depths, indicating that AH-N can be affected by soil management practices even when TN showed no major changes. The distinct distribution of AH-N across soil sampling sites and depths indicates that depths greater than 20 cm should be considered when calibrating the AH-N index for N fertilizer recommendations for flooded rice in Southern Brazil.     

Effects of restricted feed intake on heat energy by different goat breeds

Sixteen Boer goat doelings, 16 Spanish doelings, and 8 Angora doelings and 8 wethers, 283, 316, and 330 d of age initially (SEM = 5.0), respectively, were used to evaluate effects of nutrient restriction on heat energy (HE). During the first and second 10-wk phases, 8 animals of each breed were fed a 50% concentrate pelletized diet at a level adequate for maintenance and moderate energy accretion (CONT). Other animals were fed approximately 50% of these amounts in phase 1 relative to initial BW, followed by the greater level of feeding in phase 2 based on initial or actual BW when greater (REST). Average daily gain was 43, -20, 16, -78, 8, and -48 g in phase 1 (SEM = 5.0) and 26, 44, 50, 65, 27, and 32 g in phase 2 (SEM = 3.5) for Angora-CONT, Angora-REST, Boer-CONT, Boer-REST, Spanish-CONT, and Spanish-REST, respectively. Total HE was greater for CONT vs. REST in both phases (P < 0.001), greater in phase 1 for Angora than for Boer (P < 0.01) and Spanish (P < 0.01), and greatest (P < 0.01) in phase 2 among breeds for Angora [481, 347, 430, 356, 424, and 338 kJ/kg of BW(0.75) per day in phase 1 (SEM = 11.1), and 494, 479, 445, 397, 444, and 406 kJ/kg of BW(0.75) per day in phase 2 (SEM = 11.3) for Angora-CONT, Angora-REST, Boer-CONT, Boer-REST, Spanish-CONT, and Spanish-REST, respectively]. Equations describing the temporal pattern of HE (kJ/kg of BW(0.75) per day), expressed as a percentage of the wk-0 value and corrected for corresponding breed × week CONT means, in phase 1 were 95.8 ± 2.43 - (8.18 ± 1.144 × week) + (0.655 ± 0.1098 × week(2)) for Angora (R(2) = 0.58), 95.3 ± 2.63 - (4.34 ± 1.237 × wk) + (0.271 ± 0.1187 × wk(2)) for Boer (R(2) = 0.41), and 97.4 ± 2.21 - (4.69 ± 1.068 × wk) + (0.282 ± 0.1021 × wk(2)) for Spanish (R(2) = 0.53). Phase 2 equations were 78.9 ± 2.22 + (8.74 ± 1.036 × wk) - (0.608 ± 0.0095 × wk(2)) for Angora (R(2) = 0.60), 77.5 ± 2.10 + (3.30 ± 0.978 × wk) - (0.153 ± 0.0942 × wk(2)) for Boer (R(2) = 0.39), and 80.6 ± 2.50 + (4.50 ± 1.165 × wk) - (0.208 ± 0.1122 × wk(2)) for Spanish (R(2) = 0.43). These equations indicate that changes in HE in response to nutrient restriction and realimentation were more rapid and of greater magnitude in Angora vs. Boer and Spanish. The temporal pattern of decline in HE by Boer and Spanish during restriction was similar, but the subsequent rise with realimentation was slower and smaller for Boer. In conclusion, most appropriate methods of predicting change in the maintenance energy requirement during and after periods of limited feed intake may differ among breeds of goats.     

日本大耳白兔、新西兰兔血液蛋白多态性的研究

采用垂直板聚丙烯酰胺凝胶电泳法对日本大耳白兔、新西兰兔血液中的血清转铁蛋白 (Tf)、前转铁蛋白 (Prt)、后白蛋白 (Po)、血液结合素 (Hp)、红细胞酯酶 (ES - 1、ES - 2和ES - 3)等 7个蛋白座位进行测定。结果表明 :这 7个座位均呈多态。在多态座位中 ,Tf、Prt、Po、Hp、ES - 1、ES - 2、ES - 3分别出现 3、3、6、3、3和 3种表型 ,受 2、2、3、2、2和 2个共显性等位基因控制。X2 检验表明 ,新西兰兔在这 7个座位上均处于平衡状态 (P >0 .0 5 ) ,日本大耳白兔在Tf、Po、ES -1、ES - 34个座位处于平衡 (P >0 .0 5 ) ,而在Prt、Hp、ES - 2出现不平衡状态 (P <0 .0 5 )。