低温弱光对苗期紫花苜蓿根颈生理特性的影响

以秋眠级不同的2个紫花苜蓿Medicago sativa品种(巨人201和WL414)为试验材料,研究了其在低温(0~5℃和5~10℃)与弱光[50和100μmol/(m2.s)]互作处理条件下的生理响应。结果表明:紫花苜蓿根颈在低温弱光胁迫下启动了自身应激机制,对逆境胁迫做出了适应性反应,相同弱光条件下,低温0~5℃比5~10℃对根颈的影响显著,过氧化物酶活性上升幅度较小,而超氧化物歧化酶活性的下降和丙二醛含量的增加幅度均较大;相同低温处理,弱光50μmol/(m2.s)处理对根颈生理指标影响更为显著,过氧化物酶活性上升、超氧化物歧化酶活性下降和丙二醛含量增加幅度大于弱光100μmol/(m2.s)处理;巨人201各项指标的变化都优于WL414,表明巨人201抗寒耐弱光能力都可能优于WL414。     

碱茅耐盐性的研究

对碱茅不同生育期的耐盐性试验表明：碱茅成株的耐盐性强，种子和苗期的耐盐性低。种子对硫酸盐土混合盐、碳酸钠单盐和氯化钠单盐室内萌发的耐盐度分别是（溶液浓度）３．４７％、１．０８％、１．５８％。种子出苗期适宜的土壤盐渍度为１．７１２％，临界盐渍度为３．１０％。苗期以后耐盐性逐渐提高，可在２．４７～２．７９％的土壤盐渍度下生长发育正常。成株的耐盐度高达４．２４８％。田间播种碱茅草在０～１０ｃｍ土壤含盐量１．６５％以下时，可以正常出苗。盐分达到１．８５％时，需要加大实际播量，以便全苗。     

苗期低温胁迫下烯效唑对红小豆根系抗寒生理及产量的影响

为探讨烯效唑(S3307)在寒地红小豆生长中缓解低温伤害、保护根系的作用,建立红小豆抗冷生产技术体系,达到保产增产的目的,在盆栽条件下,以两个红小豆品种宝清红(耐冷型品种)和天津红(冷敏型品种)为材料,于苗期在人工气候室进行低温(15℃,分别持续1,2,3,4,5d)和叶面喷施20mg·L^-1S3307处理,对红小豆根系抗寒生理指标、产量及不同温度敏感性红小豆品种的S3307响应差异进行测定和分析。结果表明,幼苗期低温导致红小豆根系逆境生理指标发生变化,低温诱导SOD、POD和CAT活性的增强,引起可溶性糖和脯氨酸含量的提高,同时也促使MDA含量上升,最终导致红小豆产量下降。与常温条件相比,喷施清水的宝清红和天津红,低温处理3d时,可溶性糖含量分别提高了59.21%和52.57%;脯氨酸含量分别提高了10.12%和25.39%;SOD、POD和CAT活性分别提高了14.92%和11.01%、5.93%和0.75%、53.33%和13.33%。低温处理5d时,可溶性蛋白含量分别提高了6.27%和3.15%;MDA含量分别显著提高了45.41%和51.08%、产量分别显著下降了19.39%和41.69%。低温条件下,喷施S3307与喷施清水的宝清红和天津红相比较,处理3d时,可溶性糖和脯氨酸含量分别提高了22.01%和0.46%、8.55%和1.40%;SOD活性分别提高了13.45%和24.06%、POD活性分别显著提高了23.60%和15.95%,CAT活性分别提高了4.35%和5.88%。处理5d时,MDA含量分别降低了9.05%和4.37%;产量分别显著提高23.06%和43.88%。综上,S3307通过增加可溶性物质和脯氨酸的含量,提高保护酶活性,降低MDA含量,从而缓解低温伤害,进而降低低温对红小豆造成的产量影响。     

Breeding distribution and maternal genetic lineages in Lulu,a dwarf cattle population in Nepal

Lulu is a dwarf cattle population bred in the Mustang district of western and central Nepal. This area is located around the habitat boundary between Bos taurus and Bos indicus. The peculiarities of Lulu are their small size (weight range in the adult female: 68–153 kg) and rearing in high mountain areas at 2800 m to 4000 m in altitude. There were 5770 head of Lulu cattle in the Mustang district in 1998, 4333 females and 1437 males. The morphological appearance of Lulu is Bos taurus. However, one of the five Lulu studied in Kagbeni, Mustang had a Bos indicus mitochondrial DNA type based on the D‐loop sequence, while the other four were Bos taurus. It is suggested that there are hybrids of Lulu with Bos indicus maternal lineage in a mostly taurine‐breed genetic background. Steps must be taken to preserve the unique Lulu.     

Ostrich meat: Production,quality parameters,and nutritional comparison to other types of meats

The poultry industry is considered one of the most efficient industries in producing animal protein. Poultry production consists of several main segments: broilers, commercial eggs, turkeys, ducks, and other poultry, including geese, guinea-fowl, pheasants, quail, and ratites. Currently, ostrich meat is marketed as a healthy red meat because it is characterized by high polyunsaturated fatty acid contents, low saturated fatty acid content, and low cholesterol level compared with red meats, such as beef, while tasting similar to lean beef. Ostrich meat contains lower sodium and higher iron contents than other kinds of meat, making it preferable to hypertensive people and those with anemia. Taken together, ostrich meat is considered as an ideal red meat for individuals seeking healthier lifestyle. Moreover, many different ostrich products, such as leather and feathers, are used by people. The current review paper considers the quality characteristics of ostrich meat, including physical traits, and compares it to other types of meats, such as bovine and other poultry meats.     

去势术对雄性中华田园犬脂代谢的影响

[目的] 研究去势术对雄性中华田园犬脂代谢的影响。[方法] 将12只年龄、体重相近的中华田园犬分为非手术组和去势组,对去势组中华田园犬进行去势手术,观察并测定术前第1天、术后第14天、术后第21天血清中甘油三酯（TG）、总胆固醇（TC）、低密度脂蛋白（LDL）、高密度脂蛋白（HDL）含量,以非手术组作为对照,分析去势术对雄性犬脂代谢的影响。[结果] 去势组与非手术组相比,血清中TG含量在第14天到第21天显著上升;血清中TC含量相比非手术组呈下降趋势;HDL第14天和第21天都低于非手术组;LDL都高于非手术组,整体呈上升趋势。[结论] 去势手术会影响雄性中华田园犬机体脂类代谢,会导致去势犬甘油三酯升高,总胆固醇和高密度脂蛋白下降,低密度脂蛋白上升。     

The Breeding Season of the Multimammate Mouse Praomys (Mastomys) Natalensis (A. Smith) in the Transvaal Highveld

Certain aquatic Oligochaeta live successfully in organic-polluted waters while others cannot tolerate such conditions. Tubifex tempUtoni Southern and Llmnodrttus hoffmeisteri (Clap.), two non-gilled species, are compared to Branchiura sowerbyi (Beddard) and Dero nivea (Aiyer), two gilled species, concerning their haemoglobin concentration, the influence of low oxygen availability on the respiration rate and their reactions in an oxygen gradient. In contrast with L. hoffmeisteri and T. templetoni where a very narrow range of respiration dependency (pO₂, 0-12 mm Hg) is found, B. sowerbyi and D. nivea have a level of respiratory dependence from pO₂, 0-131 mm Hg. Haemoglobin concentrations are 6,238 - and 6,452 g/100 cm² blood in L. hoffmeisteri and T. templetoni and 3,011 and 1,611 g/100 cm² in B. sowerbyi and D. nivea respectively. In the oxygen gradient all four species have a preference for water with a high oxygen content.     

能量对低出生体重仔猪死亡率、断奶重和初乳摄入量的影响

文章探讨了能量补充对低出生体重仔猪的死亡率、断奶体重、日增重及初乳摄入量的影响。处理组选择22头母猪所产的306头活仔猪,其中极低出生体重(<1 kg)72头,低出生体重(1~1.2 kg)77头,分别于出生时和出生后8~12 h口服能量补充剂。对照组选择24头母猪所产的340头活仔猪,其中极低出生体重81头,低出生体重74头。结果显示:能量补充较对照组显著降低了极低出生重仔猪哺乳3 d的死亡率(P <0.05),有降低低出生重仔猪死亡率的趋势(P=0.07)。总的来说,能量补充剂有降低仔猪哺乳3 d死亡率的趋势(P=0.06)。能量补充较对照组对极低出生重仔猪哺乳7和21 d存活优势率显著提高了4.04和3.59倍(P <0.05)。对照组较处理组显著提高了仔猪的断奶重(P <0.05)。对照组与处理组对仔猪的日增重、初乳摄入量及出生产量的影响均无显著差异(P> 0.05)。处理组母猪初乳产量在数值上比对照组低(P> 0.05),但处理组母猪初乳产量均匀性在数值上较对照组好。综上所述,能量补充通过为极低出生体重仔猪直接提供能量而不是通过提高初乳的摄入量来降低其断奶前的死亡率。     

假俭草体细胞抗寒突变体的获得及其SRAP分子鉴定

假俭草抗寒性差是限制其广泛应用的主要因素之一。本研究目标是以优良假俭草选系E-126为材料,经低温诱导和筛选获得体细胞抗寒突变体。结果表明,假俭草种子诱导的愈伤组织在继代培养的过程中,经0℃的低温条件下培养26 d,获得了2块存活的愈伤组织,该愈伤组织经过继代增殖后,进行分化、生根和移栽,获得株系1和株系2。苗期外部形态观察结果表明,假俭草低温诱导的株系1、株系2和对照在叶色、叶毛、叶长和叶宽上均没有显著性差异。半致死温度分析结果表明,株系1、株系2以及对照叶片半致死温度(LT₅₀)分别为-6.646,-6.546和-5.351℃,处理与对照之间差异显著,且都低于对照,但株系1和株系2之间无显著性差异。SRAP的结果表明,假俭草低温诱导的株系1和株系2在110,230以及240 bp处均存在相同特征带,表明假俭草体细胞突变体植株的变异稳定且在分子水平与对照存在差异,但株系1和株系2无差异。因此,株系1和株系2可作为同一体细胞抗寒突变体株系加以利用。     

摄入不同能量的围产期乳牛肝低密度脂蛋白受体mRNA丰度的比较

将30头健康、经产、处于围产期的黑白花乳牛随机分为3组，每组10头。从产前28d开始，低能量组乳牛饲喂《中国奶牛饲养标准（2000）》减少20％日粮（能量摄入80％），对照组乳牛饲喂《标准》日粮（能量摄入100％），高能量组乳牛饲喂《标准》增加20％日粮（能量摄入120％），产后各组乳牛均饲喂标准日粮。至产后第56d结束试验；采用内对照RT-PCR方法检测摄入不同能量的围产期乳牛肝活体组织低密度脂蛋白受体（LDLR）mRNA丰度。结果，不同能量组乳牛肝LDLR mRNA丰度产前至产后均呈现先升高后降低的趋势。100％和120％能量组肝LDLR mRNA丰度在产后14d达最大值，且产后均高于产前（产后56d除外，P〈0．01或P〈0．05）；而80％能量组产后1d即达到最大值，产前14d至产后14d，LDLR mRNA相对表达量显著高于100％和120％能量组；产后28～56d，120％能量组显著高于80％和100％能量组（P〈0．01）。表明围产期乳牛能量摄入水平对肝LDLR mRNA丰度有显著影响。