刈割频度、播种比例和施肥量对牛鞭草和白三叶混播草地牧草产量的影响

在不同刈割频度、施肥量和混播比例下,对混播草地牛鞭草和白三叶不同种群年总产草量进行了研究。结果表明,刈割频度对产草量的影响最大,其差异达到极显著水平(P<0.01),其中刈割频度为5次的处理鲜草总产量最高。施肥量和播种比例的互作效应对总产草量的影响差异也达到了极显著水平(P<0.01);其中施肥水平低,牛鞭草混播比例低的处理总产草量高;施肥水平高的处理,牛鞭草混播比例高的则总产草量高,而白三叶则相反。因此,牛鞭草和白三叶的混播在合理的管理措施下是有可能的;同时为了达到高产优质,初步认为刈割间期以45d,较高的施肥量和混播比例以2:1为宜。     

不同农艺措施对牛鞭草和白三叶混播草地产量及密度的影响

在不同刈割频率、施肥量和混播比例下,对混播草地牛鞭草和白三叶不同种群产量、地下生物量及分蘖数进行了研究.结果表明,刈割频率对产量的影响最大,但刈割时间,尤其是秋季最佳刈割时间对维持草地牧草比例平衡是相当重要的.同时,牧草的地下生物量与地上产量相关,刈割不利于禾本科牧草地下生物量的积累.施肥量和播种比例的互作效应对总产量的影响差异也达到了极显著水平(P＜0.01).     

刈割次数、施肥量及混播比例对牛鞭草和白三叶混播草地牧草品质的影响

在不同刈割频率、施肥量和混播比例下,对混播草地牛鞭草Hemarthria compressa和白三叶Triflium re-pen不同种群产量、地下生物量及分蘖数进行了研究。试验表明,刈割4次牧草蛋白质的收获量与刈割5次的差异不显著(P>0.05),而酸性洗涤纤维的收获量各处理间差异极显著(P<0.01),其中以刈割4次的最高,为1 135.1 g/m2。当刈割次数适当时,牛鞭草粗蛋白的收获量随着施肥量和禾草混播比例的增加而提高。     

不同农艺措施对牛鞭草和白三叶混播草地产量及密度的影响

在不同刈割频率、施肥量和混播比例下,对混播草地牛鞭草和白三叶不同种群产量、地下生物量及分蘖数进行了研究。结果表明,刈割频率对产量的影响最大,但刈割时间,尤其是秋季最佳刈割时间对维持草地牧草比例平衡是相当重要的。同时,牧草的地下生物量与地上产量相关,刈割不利于禾本科牧草地下生物量的积累。施肥量和播种比例的互作效应对总产量的影响差异也达到了极显著水平(P<0.01)。     

刈割方式对扁穗牛鞭草与白三叶混播草地竞争的研究

试验对扁穗牛鞭草和白三叶混播草地在不同刈割方式下草地群落的密度组成变化、不同层次生物量和相对竞争强度进行了研究。结果表明：扁穗牛鞭草种群密度受留茬高度影响显著,对草层高度不明显,刈割时的草层高度30cm和留茬高度10cm的刈割方式对扁穗牛鞭草有利,此时相对竞争强度较低,扁穗牛鞭草的竞争能力较高,由于白三叶前期生长迅速,占据了地面的空间抑制了扁穗牛鞭草的生长,扁穗牛鞭草草层结构一直处于一种不稳定的状态,最终被排挤出系统。     

白三叶和狗牙根混播群落种间竞争的动态研究

对白三叶和狗牙根混播群落种间竞争的动态关系进行了研究。结果表明:在各处理中以C处理的地上生物量最高,为4584g/m2,与其它各处理生物量间差异极显著(P<0.01);而A处理单播白三叶生物量最低,为2014g/m2。在不同刈割时期,白三叶在混播群落中的比例逐渐下降;而狗牙根与之相反,且刈割对杂草起到了一定的抑制作用。试验前期,白三叶的竞争率大于狗牙根,随着气温的升高,狗牙根的竞争力占主导地位。如以获取最大生物量为目的,以白三叶50% 狗牙根50%处理的组合最好。     

施氮和刈割频度对蕹菜再生及饲草产量和品质的影响

田间试验研究了施氮和刈割频度对蕹菜(Ipomoea aquatic)再生及饲草产量和品质的影响。结果表明:蕹菜再生草鲜草、干物质产量均随着施氮量的增加而增加,但随着刈割频度的增大而降低。在施氮量277.2 kg/hm2和415.8 kg/hm2处理下,蕹菜再生草鲜草产量分别达到75 441.1 kg/hm2和82 774.2 kg/hm2,但两者差异不显著(P0.05)。再生草产量与株高和叶片数呈极显著正相关。再生生长期(2008年6月24~10月22日)刈割4次处理的再生草产量还与分枝数呈极显著正相关。再生草粗蛋白含量随着施氮量的增加而增加,但随着刈割频度的增大而降低。再生草干物质体外消化率随施氮量和刈割频度的增加而增加,而酸性洗涤纤维含量则随施氮量和刈割频度的增加而降低。     

混播比例和刈割期对混播草地产量及品质影响的研究

在新疆石河子进行了不同混播比例和不同刈割期对紫花苜蓿Medicago sativa和无芒雀麦Bromus innermis混播草地产量及品质影响的研究。结果表明：以紫花苜蓿50%（7.5 kg/hm2）+无芒雀麦50%（15 kg/hm2）混播比例的混播草地产草量最高,达到21.3 t/hm2,刈割期处理T2（紫花苜蓿初花期）产草量最高。刈割期对紫花苜蓿品质存在着明显的影响。处理T1（紫花苜蓿现蕾期）的粗蛋白含量最高,中性洗涤纤维和酸性洗涤纤维含量最低（P<0.05）;刈割期对混播草地无芒雀麦和紫花苜蓿品质存在一定的影响,其中混播处理A1（紫花苜蓿与无芒雀麦5∶5）紫花苜蓿和无芒雀麦的品质较好。     

刈割对白三叶种子及草产量的影响

刈割期是影响白三叶种子产量和草产量的主效因子;间隔期越短,白三叶在总产草量中所占比例越高;留茬过高(10 cm)或过低(5 cm)、间隔期过长(45 d)或过短(15 d)均对种子生产不利;其中以30 d-8 cm种子产量最高(412.9kg/hm²),极显著高于其余处理(P<0.01),且杂草量少、干草产量4505.3 kg/hm²,品质高,其中白三叶所占比例为46.97%;15 d-10 cm干草产量最高(11011.4 kg/hm²);15 d-5 cm白三叶干草产量最高(4422.1 kg/hm²)。     

刈割次数、施氮量和豆禾比例对混播草地产量及品质的影响

试验选择豆禾比例、施氮量和刈割次数3个试验因子,对海发白三叶与纳雍鸭茅混播草地建立综合管理优化模式,以确定最佳的管理因子,并对混播草地营养成分进行了分析.结果表明,豆未比例为1:3、施氮量为300kg/hm2、刈割6次时,鲜草产量达73.00t/hm2,粗蛋白质含量达17.22%,粗脂肪含量为5.34%,同时杂草入侵最少,是建植海发白三叶与纳雍鸭茅混播草地最理想的试验方案.     

Anaesthesia and analgesia of the donkey and the mule

The number of donkeys and mules throughout the world is stable, and awareness of their use and concern for welfare, pain recognition and treatment are receiving increasing veterinary interest. Therefore, accurate information about anaesthesia and analgesia in donkeys and mules is important to ever more equine practitioners. Since donkeys are physiologically and pharmacologically different from horses, knowledge on species specific aspects of anaesthesia and analgesia are very important. Mules combine elements from both donkey and horse backgrounds, leading to great diversity in size, temperament and body type. Physiologically, they seem to resemble horses more than donkeys. This review highlights the current knowledge on various anaesthetic and analgesic approaches in donkeys and mules. There is still much information that is not available about donkeys; in many circumstances, the clinician must use available equine information to treat the patient, while monitoring carefully to observe for differences in response to therapy compared to the horse.     

Ultrasonographic examination of the caecum and the proximal and spiral ansa of the colon of cattle

The large intestine of 10 cows was examined from the right abdominal wall with a 3.5 MHz linear transducer. The cows were then slaughtered, and the organs were re-examined in a water bath. The caecum was visualised from the middle region of the abdominal wall. It ran caudo-cranially, varied in diameter from 5.2 to 18.0 cm and was situated immediately adjacent to the abdominal wall. The lateral wall of the caecum appeared as a thick, echogenic, crescent-shaped line. It could be visualised as far cranially as the 12th intercostal space. Although its junction could not be identified, the proximal ansa of the colon was recognised on the basis of its anatomical position and its diameter, which was smaller than that of the caecum. The spiral ansa of the colon and the descending colon were situated dorsal to the caecum and could be identified by moving the transducer horizontally along the abdominal wall to the last rib. The spiral ansa of the colon was situated ventral to the descending colon, and its walls appeared as thick echogenic lines. In a contracted state, the spiral colon had the appearance of a garland.     

The behavior and the husbandry conditions of small laboratory animals--possibilities and limits of the evaluation of the appropriateness and fairness of the treatment of animals

Ethological studies are important means to evaluate the behaviour of small laboratory animals (mouse, rat, guinea-pig and rabbit) and their housing conditions. At any rate, the only sparse range of body expressions, the smallness and preference of night activity of these animals and the erratic occurrence of essential behaviour patterns make the investigations more difficult. On the other hand, the standardization of laboratory housing and the genetic definition of these animals turn out to be favourable. By this way, behaviour-environment-relationships are suitable for evaluation. Taking into consideration methodical and biological restrictions, the specific activities such as fight, relaxed resting behaviour and play as well as unbalanced behaviour patterns and stereotypes can be taken as means of evaluation. Particularly in mice and rabbits, upright position and space consuming activities will be possibly restricted by cage sizes.     

Effects of age and diet on the development of the pancreas and the synthesis and secretion of pancreatic enzymes in the young pig

Effects of age and diet composition on amylase, trypsin and chymotrypsin activities in the pancreas and intestinal contents, pancreas weights and body weights were determined from birth to 56 d. A total of 120 pigs, five to seven pigs/litter from 18 litters, were slaughtered at birth, 14, 27, 29, 31, 42 and 56 d. Litters were allotted to dietary treatments (corn-soy, A; corn-soy + 20% dried whey, B; corn-soy + 5% lard, C) and offered these diets as creep feed at 14 d. All pigs were weaned at 28 d, placed in elevated nursery pens and fed their respective diets. Total activities of amylase, trypsin and chymotrypsin in the pancreas and small intestine increased (P less than .05) with age. Both trypsin and amylase activities, measured per kilogram body weight or gram pancreas weight, were low at 29 d in the intestine and increased to 56 d. Pigs on diet B had the highest level of trypsin and chymotrypsin in the intestinal contents (P less than .05). Trypsin activity in the pancreas (units/kg body weight) was lowest (P less than .05) for pigs on diet B and highest (P less than .05) for those on diet C (units/g pancreas and units/kg body weight). Amylase activity (units/kg body weight) was lower (P less than .05) in the pancreas for pigs on diet B than for those on diets A and C. Pigs on diet A had lower (P less than .01) intestinal amylase activities than those on diets B and C. Enzyme activities in the intestinal contents and pancreas were low following weaning. In the pancreas, activities decreased at 31 d.(ABSTRACT TRUNCATED AT 250 WORDS)     

Relation between the concentration of sodium and potassium in the erythrocytes of dairy cows and the concentration of these elements in the plasma and urine and the level of blood glucose

Blood and urine samples of 180 dairy cows from 12 herds were examined. Sodium and potassium concentrations were determined in erythrocytes, whole blood, plasma, urine, and glucose concentration in blood: the interrelations were compared. Sodium and potassium concentrations in erythrocytes were 85.15 +/- 11.45 mmol/l, and 25.93 +/- 7.81 mmol/l, respectively. A statistically significant relation was found between sodium and potassium concentrations in erythrocytes (r = 0.3467+++) and the content of electrolyte in blood cells and in whole blood (Na: r = 0.5336+++; K: r = 0.3561+++). No statistically significant relation of intraerythrocyte concentration of both electrolytes was confirmed with respect to the other characteristics (sodium and potassium concentrations in plasma and urine, and glucose concentration in blood). In the conditions of routine laboratory diagnostics in clinically healthy cows, determinations of intraerythrocyte sodium and potassium do not broaden possibilities of evaluating the metabolic state of these electrolytes and cannot be used as the characteristics of energy insufficiency. The cannot replace the analyses performed in serum and urine.     

貉,蓝狐,银狐的胃及十二指肠内嗜银细胞形态分布的研究

本文应用Ｆｏｒｔａｎａ—Ｍａｓｓｏｎ嗜银颗粒染色法研究了貉、蓝狐、银狐的胃及十二指肠内嗜银细胞的形态分布。结果表明：三种动物胃幽门腺中，嗜根细胞数量最多，呈锥状，嗜银颗粒较粗，密度大、染成深黑色。在胃底及胃贲门腺区、嗜银细胞数量少。在十二指肠部嗜银细胞呈蝌蚪形，嗜银颗粒细，呈黑褐色，密度较小。嗜银细胞的分布密度在三种动物中具有一定的差别。     

Liquid flow and capacity of the caecum and colon of the horse

The rate of flow of fluid from the caecum and from the large colon was measured in four Shetland-type ponies fed a hay diet. In two ponies with cannulas in the caecum and at the origin of the right ventral colon, a continuous intracaecal infusion of a solution of chromium EDTA was used and samples were obtained from the cannula at the origin of the right ventral colon. Based on four determinations, the liquid flow from the caecum was 54.2 +/- 1.89 litres d-1. In the other two ponies with cannulas in the origin of the right ventral colon and near the end of the right dorsal colon, a continuous infusion of chromium EDTA was made into the right ventral colon and samples were obtained from the right dorsal colon. The flow rate towards the end of the dorsal colon was 49.4 +/- 1.25 litres d-1, based on four determinations. The capacities of the caecum and large colon after death were 7.0 +/- 0.8 and 17.7 +/- 3.7 litres, respectively.     

Conduction velocities and reflexes of the proximal and distal parts of the saphenous nerve of the dog

The maximal conduction velocities of compound-action potentials in the proximal and distal parts of the saphenous nerve were determined by averaging potentials evoked and recorded through needle electrodes. Antidromic, triphasic compound-action potentials unipolarly recorded from the distal part of the saphenous nerve were of the same minimal latency as potentials having 4 phases which were recorded bipolarly from the same site. However, the unipolarly recorded potentials were of greater amplitude. Monophasic compound-action potentials were recorded through bipolar chlorided silver electrodes from the surface of fascicles of the distal part of the saphenous nerve. The maximal conduction velocity of these potentials was in agreement with the conduction velocity of compound-action potentials of the distal part of the saphenous nerve which were evoked and recorded through subcutaneous needle electrodes. The specificities of the stimulating and recording sites were verified by recording before and after the saphenous nerve was cut between the stimulating and recording sites. Mean conduction velocities were 62.3 +/- 2.0 m/s for the distal part of the saphenous nerve and 66.3 +/- 2.2 m/s for the proximal part of the saphenous nerve. Reflex-evoked muscle activity was elicited in the ipsilateral tensor muscle of the fascia lata and semimembranous muscle after electrical stimulation of the saphenous nerve through subcutaneous needle electrodes. The effects of various stimulus intensities on the latency and duration of these reflex-evoked muscle potentials were determined.