Respiratory Characteristics of the Blood of Labeo Umbratus (SMITH) and Labeo Capensis (Smith)

Various respiratory characteristics of mudfish blood were investigated. Oxygen and carbon dioxide contents of mixed venous blood were 1,17±0,53 and 11,35±1,65 vol. % respectively. Blood oxygen dissociation curves showed P₅₀ values of 11,84±3,1; 13,77±2,0 and 18,05±4,7 mm Hg at CO₂, concentrations of 0-1%, 4-5% and 9-10%. A marked Bohr effect of —0,59 was observed and the Haldane effect was found to be relatively low. No differences could be observed between the characteristics of L. umbratus and L. capensis blood.     

Aspects of the pathology of Lamproglena clariae (Copepoda: Lernaeidae) on gills of Clarias gariepinus from the Vaal River system,South Africa

Lamproglena clariae attaches to gill filaments of Clarias gariepinus, penetrates the gill tissue and consumes blood. Hence, the purpose of this study was to investigate the mechanical damage caused by this parasite on gill filaments of the host. Infestation intensity and haematocrit values of fish blood were determined and correlated. Fish were killed, gills dissected out and observed with a dissection microscope. Gill filaments with adult females in situ were fixed in a solution of alcohol, formaldehyde and acetic acid and preserved in 70% ethanol. Fixed specimens were studied by histological examination following staining with Heidenhein’s azan solution. Gross morphology revealed varying degrees of swelling of gill filaments near the attached specimens of L. clariae. Epithelial hyperplasia, resulting in fusion of gill lamellae and necrosis of the host tissue in the vicinity of the parasite were revealed through histological examination. No correlation was evident between the infestation intensity and fish haematocrit values. Although results showed that L. clariae causes localized infestation, high intensity of infestation may be detrimental to the fish. Hyperplasia of epithelial tissue resulting in fusion of lamellae would result in restriction of air passages and thus hinder the process of respiration of the host.     

The effect of temperature and salinity on oxygen consumption in the brachyuran crab Cyclograpsus punctatus (Crustacea: Decapoda: Grapsidae)

The aquatic oxygen consumption of the estuarine brachyuran crab, Cyclograpsus punctatus, was investigated after a 24-hour acclimation period at different temperature (12.5, 20, 30°C) and salinity (9, 17.5, 35, and 44°) combinations . Salinity had no significant effect on oxygen consumption at 12.5 and 20°C in both large and small crabs. At 30°C and 44°, however, the rate of oxygen consumption declined in large crabs (from 0.233 to 0.176 mg O₂ g wwt/h) and increased in small crabs (0.300 to 0.469 mg O₂ g wwt/h). There was also a significant increase in the oxygen consumption (0.300 to 0.536 mg O₂ g wwt/h) of small crabs at the high temperature/low salinity combination. Temperature had a significant effect on the rate of oxygen consumption at all salinities, with Q₁₀ values ranging from 1.16 to 2.85. In all cases the mass-specific oxygen consumption rate of small crabs was higher than that of large crabs. The results suggest that the confinement of this species to the lower reaches of estuaries may, in part, be due to physiological constraints on juveniles and small individuals.     

旱养模式下饲养密度和公母配比对肉种鸭生产性能的影响

本研究旨在探讨旱养模式下不同饲养密度、不同公母配比对SM3樱桃谷种鸭生产性能的影响。选择24周龄产蛋期父母代SM3樱桃谷种鸭21600只。将试验鸭随机分为饲养密度调整为2、3、4、5、6只/m25组,每组3个重复,每个重复1200只,公母配比均为1:4.5,试验至48周龄结束。对存活率、产蛋率、种蛋合格率及42周龄种蛋受精率指标进行测定和分析,结果表明:在旱养条件下肉种鸭饲养密度以4只/m2最适宜。选择24周龄产蛋期父母代SM3樱桃谷种鸭14400只。将试验鸭随机公母配比为1:4、1:5、1:6、1:74组,每组3个重复,每个重复1200只,各组密度均为4.2只/m2,试验至65周龄结束。通过测定产蛋率、种蛋合格率和受精率,用与密度试验相同的分析方法,结果表明:1:5的公母性别比例为最佳配比。     

微山湖河蟹养殖区与非河蟹养殖区细菌胞外酶的比较研究

为了研究微山湖河蟹养殖区与非河蟹养殖区水体和底泥中异养细菌胞外产酶（蛋白酶、淀粉酶、脂肪酶、脲酶）的差别．对这2处环境中的微生物进行了初步筛选和分离,得到25株菌,分别在含有蛋白质、脂肪、淀粉、脲的固体培养基上培养观察。并测量记录菌落和菌圈大小。结果表明,河蟹养殖区产蛋白水解酶和脂肪水解酶的细菌明显多于非河蟹养殖区,而产淀粉水解酶和脲酶的细菌数量两者相差不大。     

疏勒河流域中下游景观格局特征与景观生态建设

利用疏勒河流域中下游1990、1994和1999年1∶10万土地利用现状图、地形图和TM遥感影像及相应的GIS获取的数据,调查分析其景观格局变化.结果表明,疏勒河流域景观格局特征为:在浩瀚的戈壁上点缀着带状的绿洲,而在这带状的绿洲中,其景观要素的分布也呈圈带状,以河流廊道为核心,从内向外依次为农田、林地和草地、盐碱地、沙地、风蚀荒地.其景观格局变化特征为耕地、盐碱地、沙地、风蚀荒地面积不断扩大,林地和草地面积不断减小.针对其特征及变化,从景观生态理论及方法的角度,提出了以绿洲建设、河流廊道建设和荒漠植被建设为核心的景观生态建设方案.     

略论西北地区渔业发展现状及对策

通过对西北地区渔业现状的分析，从中挖掘出西北地区渔业落后的社会经济原因，并结合当前的社会经济状况和渔业发展形势，总结了西北地区渔业发展的优势所在，以此为基础提出了加强市场宣传和资源开发、引进资金和技术以及政策引导等发展西北渔业的几点建议。     

Molecular sexing of Japanese cormorants used for traditional fishing on the Nagara River in Gifu City

The Japanese cormorants used in traditional fishing in Japan are wild derived and their sex cannot be determined from their appearance. Applicability of molecular sex determination based on the size difference between CHD1Z and CHD1W introns was confirmed in male and female Japanese cormorants whose sexes had been ascertained by pathological autopsy. All of 21 birds of unknown sex reared by a cormorant fishing master were identified as males. The molecular sexing method will provide valuable information on sex differences of wild Japanese cormorants, including tameness, trainability, behavior and fishing capability, as well as for future trials involving artificial reproduction.     

Effects of Dietary Energy Density on Plasma Glucose and Lipid Profile, Morphological Aspects and Chemical Characteristics of Adipose Tissue in Finishing Pigs

Peroxisome proliferator-activated receptor-γ (PPAR-γ) plays a pivotal role in controlling adipogenesis. We hypothesized that changes in dietary energy density might alter fat deposition in finishing pigs via modulation of the expression of PPAR-γ. To test this hypothesis, thirty female finishing pigs were fed diets containing low (LD), medium (MD) or high (HD) energy density. Blood samples were collected on day 53, and then the pigs were sacrificed to collect samples of the dorsal subcutaneous (ST), abdominal (AT) and mesenteric (MT) adipose tissue. Compared with pigs fed the MD diet, malate dehydrogenase activity was increased in the ST and MT of pigs fed the HD diet, while activity was decreased in the MT of pigs fed the LD diet (P < 0.05). Glucose-6-phosphate dehydrogenase activity was increased in all three fat depots of pigs fed the HD diet (P < 0.05) in comparison with pigs fed the MD diet. Both HD and LD diets increased the size of the adipocytes in the AT and MT (P < 0.05). Pigs fed the HD diet had a higher cell proliferation index in the ST compared with pigs fed the other two diets (P < 0.05). Compared with pigs fed the MD diet, a decreased apoptosis index was seen in the ST of pigs fed the HD diet, and in the AT of pigs fed the LD diet, as well as in the MT of both HD and LD fed pigs (P < 0.05). PPAR-γ positive percentage was elevated in the ST and MT of HD fed pigs compared with pigs fed the MD and LD diets, while it was decreased in the ST of LD compared with MD fed pigs (P < 0.05). These results suggest that dietary energy density may regulate fat deposition in finishing pigs. It is possible that feeding a high energy diet may induce fat deposition via up-regulation of  PPAR-γ expression.     

数学思维在《生态学》教学中的应用与实践

 生态学是生命科学领域相关本科专业的重要课程之一。生态学的发展和完善与数学是紧密相连的。生态学具有较强理论性和实践性,采用“渗透式”的教学方法,巧妙应用数学的理论和方法,把生态学知识进行数学抽象和逻辑推演,从而使生态学知识和数学思维有机结合。这样的教学能提高学生的学习兴趣,提升学生对生态学的认识和理解程度。     

产卵与黄鳝性转化关联研究

对产卵与未产卵黄鳝的专池周年培育,结果表明,黄鳝与常规鱼类类似,亲鳝在人工养殖条件下培育,性腺可正常发育。已产卵黄缮第2年雄化率为22.2％,间性率为27.7％,保持雌性率为51.1％。未产卵黄缮雄化率为0％.间性率为11％,保持雌性者为89％。怀卵未产黄鳝性转化率低,黄鳝正常产卵后与怀卵未产黄鳝相比较性转化率有极显著差异(P<0.01)。     

日粮能量和蛋白水平对双向选择血浆极低密度脂蛋白浓度肉鸡腹脂和产肉性能的影响

对７０８只（公母各半）５～９周龄一世代高、低极低密度脂蛋白（ＶＬＤＬ）系肉鸡进行３个代谢能水平（１３．４，１２．５，１１．６ＭＪ／ｋｇ）和３个粗蛋白水平（２２．４％，１９．４％，１６．４％）的三因子交叉的遗传－营养互作试验，以探讨肉鸡腹脂及屠体性状的遗传、营养、性别间的互作效应。结果表明：日粮对脂肪沉积的影响存在品系差异，品系与日粮代谢能互作对板油有明显影响（Ｐ＜０．０５）；日粮代谢能和粗蛋白对高ＶＬＤＬ系板油的影响大于低ＶＬＤＬ系，高ＶＬＤＬ系板油随日粮代谢能的升高而升高，而低ＶＬＤＬ系无此规律。品系与日粮代谢能互作对肌胃脂率有明显影响（Ｐ＜０．０５），日粮代谢能对低ＶＬＤＬ系肌胃脂的影响大于高ＶＬＤＬ系，而粗蛋白对高ＶＬＤＬ系肌胃脂的影响大于低ＶＬＤＬ系。品系间肌胃脂的差异在不同日粮代谢能水平下表现不一致。品系与日粮互作对产肉性状未产生明显影响。日粮代谢能与性别间的互作对腿肌率有明显影响（Ｐ＜０．０５），雌性腿肌率随代谢能水平的升高而降低。     

饲养密度和饲粮赖氨酸水平对公母分饲肉鸡生长性能、胴体组成和健康状态的影响

本试验旨在研究不同饲养密度和饲粮赖氨酸水平对公母分饲肉鸡生长性能、胴体组成和健康状态的影响.试验采用2×2×3三因子完全随机设计,选用罗斯308商品代肉仔鸡公雏1314只和母雏1530只,随机分成12个处理,每个处理6个重复(栏).试验设高、低2个饲养密度,分别为42(16公/m2或18母/m2)和26 kg/m2(1...     

Gelatinized to non-gelatinized starch ratio in the diet of Labeo rohita: effect on digestive and metabolic response and on growth

A 60-days experiment was conducted to study the optimum gelatinized (G) to non-gelatinized (NG) starch ratio in the diet of Labeo rohita juveniles with respect to digestive and metabolic response and on growth. Two-hundred and thirty-four juveniles (avg. wt 2.53 ± 0.04 g) were randomly distributed in six treatment groups with each of three replicates. Six semipurified diets either containing NG and/or G corn starch viz., T₁ (100% NG, 0% G starch), T₂ (80% NG, 20% G starch), T₃ (60% NG, 40% G starch), T₄ (40% NG, 60% G starch), T₅ (20% NG, 80% G starch) and T₆ (0% NG, 100% G starch) were prepared. The dry matter digestibility and carbohydrate digestibility were highest (p < 0.05) in T₆ group and lowest in T₃ and T₄ groups. The amylase activity in intestine increased as G:NG level increased in the diet. Protease activity in intestine was highest in T₆ group and lowest in T₁ group. Similar trend was recorded for specific growth rate, protein efficiency ratio and apparent net protein utilization. Liver glycogen, hepatosomatic index and blood glucose level increased linearly with the increasing level of G starch in the experimental diet. The results indicate that higher nutrient digestibility and growth was recorded either at low (20% G starch, T₂) or high (100% G starch, T₆) G starch fed group. But high G starch fed group (T₆) exhibits higher liver glycogen and blood glucose level, which may lead to stress due to long-term feeding. Hence, it is suggested that 20% G and 80% NG starch is optimum for better nutrient digestibility and growth in L. rohita juveniles.     

Some Reproductive and Clinical Aspects of Endotoxins in Cows with Special Emphasis on The Role of Prostaglandins

Endotoxin from Salmonella typhimurium was administered intravenously to 3 cows. It produced an immediate increase in blood prostaglandin metabolite levels causing either luteolysis or a temporary drop in progesterone concentrations depending on the degree of prostaglandin synthesis. The clinical effects on heart rate, respiratory rate, ruminai contraction rate, body temperature and other general signs were studied. The cows showed a transient increase in heart and respiratory rate and a decrease in ruminai activity. The temperature responded by a small initial decrease and a secondary increase. Other symptoms included muscular weakness and shivering, excessive salivation and diarrhoea. Plasma Ca levels showed a direct decrease and then slowly increased to initial levels in the course of several days. The role of endotoxins in Gram-negative infections and their mode of action on the body are discussed with special emphasis on the role of prostaglandins on reproductive function.     

北方山羊业发展与生态环境保护问题

分析认为将草原荒漠化和草原生态系统的破坏归咎处于山羊饲养业是一种片面的认识，山羊业，特别是绒山羊业是我国富有特色的产业且羊绒产品极具国际竞争力，正确处理山羊业与环境保护问题是当务之急，文中提出了合理化建议。     

不同NFC/NDF比对奶山羊瘤胃微生物及瘤胃pH值变化的影响

试验研究了在不同非纤维性碳水化合物/中性洗涤纤维（NFC/NDF）比饲粮条件下诱发奶山羊亚急性瘤胃酸中毒（subacute rumen acidosis,SARA）过程中瘤胃微生物区系和瘤胃pH值的变化。该试验选用6只安装了永久性瘤胃瘘管的泌乳期关中奶山羊为试验动物,采用自身对照试验法,共分4期进行,每期10d,依次饲喂NFC/NDF比为1.02（Ⅰ期）、1.24（Ⅱ期）、1.63（Ⅲ期）、2.58（Ⅳ期）的4种饲粮,以逐渐增加饲粮精料的方法诱导奶山羊发生SARA。结果表明,随着饲粮NFC/NDF比的增大,瘤胃pH值显著降低（P〈0.05）,并且瘤胃pH值下降幅度也随之加快;随着饲粮NFC/NDF比的增加,淀粉分解菌的数量增幅最显著（P〈0.01）;饲粮NFC/NDF比为1.63时,瘤胃细菌总数、乳酸杆菌及坏死梭形杆菌的数量显著增加（P〈0.05）,当该比值为2.58时,埃氏巨型球菌和反刍兽新月单胞菌的数量出现显著增多（P〈0.05）;原虫数量在Ⅳ期降至最低,而牛链球菌的数量在整个试验期并未出现明显的波动。饲粮NFC/NDF比为1.63时,瘤胃内与碳水化合物分解有关的多数细菌的数量明显增加,SARA期时增幅更为明显,而此时原虫数量为最低。     

不同日龄与性别腾冲雪鸡血液生化指标变化的研究

采集１６只６０日龄和９０日龄不同性别的云南腾冲雪鸡的静脉血,测定血清中１２个成份的含量指标。结果表明：甘油三脂、胆固醇、尿酸、肌酐和磷含量有性别、年龄差异;公鸡的甘油三脂含量大于母鸡,差异显著;９０日龄胆固醇含量大于６０日龄,差异显著;母鸡尿酸含量低于公鸡、９０日龄高于６０日龄,且随日龄增加公母间差异增大;随鸡龄增加,肌酐含量增加,公鸡增加的幅度大于母鸡;在公鸡,随日龄增大,血磷升高;在母鸡,随日龄增加,血磷下降。     

The effect of exogenous administration of oestrogens on the function of the epididymis and the accessory sex glands in the boar.

Three normal, sexually mature young boars of Swedish Yorkshire breed were treated with daily intramuscular injections of diethylstilboestrol and/or oestradiolbenzoate for a total period of 13–15 weeks. Whole ejaculates were collected on a dummy sow with an artificial vagina twice a week. The ejaculate was examined as regards semen volume, sperm concentration, sperm motility and sperm morphology. The seminal plasma was analysed for Na, K, Cl, Mg, inorganic phosphate, total protein and fructose. Testicles, epididymides and the accessory sex glands were obtained at slaughter. Material from epididymal segments A, B, D_b, F_a and F_b was collected and examined for sperm morphology. Spermatocrit, osmotic pressure and plasma concentrations of Na, K, Gl, total protein and GPC were assessed in material from epididymal segment F_a. The sex glands and the accessory sex glands were examined maeroscopically and microscopically.The semen volume, the sperm concentration and consequently the total sperm count per ejaculate showed a gradual increase during the course of the investigation. This is to be expected as the boars used were comparatively young at the beginning of the experiment. These values were all within normal limits for adolescent boars.Taking all the characteristics examined into consideration no conclusive evidence was found that an exogenic administration of oestrogens to intact boars has any influence on the function of the epididymis and the accessory sex glands.