羊草草原枯枝落叶积累的研究：枯枝落叶积累对草原生态环境及生产力的作用

枯枝落叶积累可改变原生态环境，地表温度、土壤ＰＨ值积累量呈线性负相关，蒸发量、土壤容重与积累量呈指数负相关，土壤水分、土壤孔隙度与积累量呈线性正相关，枯枝落叶积累可为植物生长创造良好的生境。土壤中主要营养物质随着枯枝落叶积累均有明显提高当积累量达６００ｇ／ｍ＾２时，有机质、Ｎ、Ｐ、Ｋ含量分别比无枯枝落叶层提高１．８倍、８８．２％、２．１５倍和３７％。枯枝落叶积累对草原生产力有促进作用，在一定范围内     

羊草草原枯枝落叶中矿质元素的动态分析

在羊草原上，因植物的枯死，输入到枯枝落叶中的矿质元素钙、镁、铁、钠、铜、锰、锌分别为０．８７６、０．８０８、０．２６１０．１１０、０．００４、０．０２６、０．０１３ｇ／（ｍ＾２．ａ），经过１ａ分解后，枯枝落叶各元素向土壤中释放的速率分别为５５％、３４％、３２％、５７％、３１％、５４％２２％。目前，枯枝落叶中矿质元素处于积累阶段，输入量大于输出量，达到稳定状态条件下，枯枝落叶中元素的含量分别为１．５     

低能量氦氖激光照射对荷瘤小鼠NK细胞活性的影响

研究低能量氦氖激光照射荷瘤小鼠对ＮＫ细胞活性的影响。选取ＢＡＬＢ／Ｃ雄性小鼠腹腔接种Ｓ１８０,接种后进行激光照射小鼠内眼角,监测了正确对照组,肿瘤对照组和７．３３、１１．００、１４．６７、２２．００、２９．３３Ｊ／ｃｍ＾２五个激光照射线能明显提高荷瘤小鼠ＮＫ细胞活性;７．３３、２９．３３Ｊ／ｃｍ＾２照射组则长高不明显。     

青山半泌乳期母羊的能量需要量研究

选用２４只山羊泌乳母羊，用饲养试验、消化代谢试验、比较屠宰试验及气体能量代谢试验等手段，研究其能量需要量。结果表明，在本试验条件下，试羊的能量消化率和代谢率分别为７０．４％和８５．０％。甲烷能占总能进食量（ＧＥＩ）的９．２０％。维持代谢能需要为５０２Ｗ＾０．７５ＫＪ／天，每产一千克标准乳（ＦＣＭ）需５０６０ＫＪ泌乳代谢能。泌乳母羊的维持效率（Ｋｍ）为０．８４５，泌乳效率（Ｋ１）为０．６３５，热增耗     

毛乌素沙地南缘禾草杂类草草地地上部生物量动态及光能转化率研究

对分布于毛乌素沙地南缘的禾草杂类草草地地上部生物量动态，净第一生产力和光能转化率进行了研究，由于过度利用，该草地群落出现退化，一、二年生植物及对家畜有害植物的盖度占草地群落总盖度的５０－６０％。４－１１月期间，其地上部生物量（ＤＭ）的变化呈单峰曲线，最大值出现在９月１３日，为９４．００ｇ／ｍ＾２，草地群落地上部净第一性生产力（ＤＭ）为８４．９４ｇ／（ｍ＾２·年），以能量计算，则为１２２５．６３ｋＪ     

东北松嫩草原碱茅群落的土壤呼吸同枯枝落叶分解释放CO2贡献量研究

应用静态气室法测定了碱茅群落的土壤呼吸和枯枝落叶分解释放CO2贡献量的季节动态,结果表明:①土壤呼吸的季节动态呈现单峰曲线,7月中旬达最大值11.4 gC/(m2@d);②土壤呼吸的季节变化与地上绿色体生物量季节动态同步;③土壤呼吸的季节动态同枯枝落叶分解速率的季节动态同步;④土壤呼吸量与0～10 cm的土壤层中的含水量显著正相关;⑤地表枯枝落叶层分解直接排放CO2量的季节动态呈现单峰曲线,7月中旬达最大值2.93 gC/(m2@d),有减缓土壤向大气排放CO2的作用;⑥枯枝落叶分解释放CO2量同现存地表枯枝落叶量显著正相关.     

河西走廊几种盐化草地第一性生产力的研究：Ⅰ地上生物量与地下生物量…

对河西走廊三盐渍化草地生物量进行定位研究的结果表明：１）海韭菜草地、小灯心草地和芦苇＋赖草草地上生物量变化均表现为单峰曲线，最大值均出现在７月上旬，其值分别为５４６、１２ｇ．ＤＭ／ｍ＾２，２６８．２６ｇ／ｍ＾２和１４０．９９ｇＤＭ／ｍ＾２三个草地当年地上部净生产力分别为５５９．０４ｇ／ＤＭ／ｍ＾２．ａ，２２６．８６ｇ．ＤＭ／ｍ＾２．ａ，８３．７４ｇ．ＤＭ／ｍ＾２．ａ。２）海韭菜草地地下生物量呈连续     

He—Ne激光免疫调节机理研究

应用不同剂量的Ｈｅ－Ｎｅ激光照射大鼠脊背正中毛皮肤，连续１４ｄ，观察不同时间；２６．４８、３９．７２Ｊ／ｃｍ＾２的Ｈｅ－Ｎｅ激光对上述指标具有一定程度的促进作用，２６．４８，３９．７２Ｊ／ｃｍ＾２的Ｈｅ－Ｎｅ激光对上述指标具有一定程度的抑制作用。     

艾蒿群落生物量初步研究

研究了陕北黄土高原森林区和森林草原地带分布面积广、在植物群落演替过程中具明显地位的茭蒿群落的生物量，测定了地上和地下生物量的季节和地带性变化。结果表明，茭蒿群落生物量季节变化明显，８月中旬地下生物量达峰值（１３８８．５７ｇ／ｍ＾２），地上生物量峰值出现在９月中旬（２３４．０５ｇ／ｍ＾２）。     

贵州足球场草坪建植及优化管理模型研究

在一定的生境和管理条件下,以修剪高度、修剪次数和施Ｎ、Ｐ、Ｋ量为因素,利用二次正交回归设计,用模糊综合评分法评定草坪质量,最佳３因子水平为：修剪高度５－７．４ｃｍ,修剪次数４－６次／月,施Ｎ量为２．５－３．７ｇ（ｍ＾２．年）,施Ｐ、Ｋ量各为１．２５－１．８５ｇ／（ｍ＾２．年）,建立了草坪质量与养护３因子间的显相关回归模型。     

Treatment of broiler litter with organic acids

Experiments for treatment of contaminated broiler litter with citric, tartaric and salicylic acids were performed. At days 2 and 6 after the treatment, pH values (using a pH-meter), the ammonia concentrations (titration with 0.1 N HCl) and the microbial cells counts were determined in both experimental and control specimens of litter. The cost of acidification of litter was also determined. Our studies showed that the treatment of the contaminated litter with 5 per cent citric acid, 4 per cent tartaric acid and 1.5 per cent salicylic acid created an acid medium with pH under 5.0 and thus reduced the microbial counts to 2.2 x 10(3)colony forming units per gram manure litter. The treatment reduced the content of ammonia in the litter and in the air under the hygienic limits, i.e. 25-50 ppm. The cost of acidification of litter with these organic acids amounted to 0.1 $ per bird and 1.5 $ per 15 birds on one square metre in a growth period of 50 days.     

青海湖地区紫花针茅型中度与重度退化草地光能转化效率的研究

通过青海湖地区紫花针茅型中度与重度退化草地群落光能转化效率的研究,结果表明,中度与重度退化样地地上部分固定能量的季节动态基本相同,都呈“单峰”曲线,在8月下旬地上部分固定的能量达到最大值,其值分别为194188KJ/m2、872.61KJ/m2。两退化样地植物群落地上部分现存量的热值大于凋落物的热值,以植物生长旺盛期热值含量最高,枯黄期次之,返青期最低。地上部分植物量与能量固定之间呈极显著的线性正相关,地上植物量每增加1g/m2,中度与重度退化样地植物群落贮存的能量将随之分别增加18.687KJ/m2、18.055KJ/m2,在地上0￣10cm区间中度与重度退化样地固定的能量分别占地上总能量的79.25%、81.15%。中度与重度退化样地地上部分对总辐射转化率的变幅分别为-0.076￣0.13、-0.022￣0.045,对太阳总辐射的转化率分别为0.03%、0.013%。     

青海湖地区紫花针茅型中度与重度退化草地光能转化效率的研究

通过青海湖地区紫花针茅型中度与重度退化草地群落光能转化效率的研究，结果表明，中度与重度退化样地地上部分固定能量的季节动态基本相同，都呈“单峰”曲线，在8月下旬地上部分固定的能量达到最大值，其值分别为194188KJ／m^2、872．61KJ/m^2。两退化样地植物群落地上部分现存量的热值大于凋落物的热值，以植物生长旺盛期热值含量最高，枯黄期次之，返青期最低。地上部分植物量与能量固定之闻呈极显著的线性正相关，地上植物量每增加1g／m2，中度与重度退化样地植物群落贮存的能量将随之分别增加18．687KJ／m^2、18．055KJ/m^2，在地上0-10cm区间中度与重度退化样地固定的能量分别占地上总能量的79．25％、81．15％。中度与重度退化样地地上部分对总辐射转化率的变幅分别为-0．076-0.13、-0.022-0．045，对太阳总辐射的转化率分别为0．03％、0．013%。     

Influence of long-term vaccination of a breeding herd of pigs against PCV2 on reproductive parameters

The objective of the study was to evaluate an efficacy of sows vaccination protocols in the herd with serious problems affecting efficacy of reproduction. The study was performed in a large pig herd with about 1200 sows. Before vaccination against PCV2, farrowing rate in this farm was about 65%. Sows, boar and replacement gilts were immunized using Circovac vaccine (Merial, France) according to producer's recommendations. Parameters of production were analyzed since 2007 until 2010 in selected batches of sows inseminated at the same weeks of the year (17th, 18th, 19th and 20th) to eliminate seasonal variability. In total, 940 sows were subjected to the study. No significant changes in management during these years were introduced. The applied protocol of sow herd long-term vaccination proved to be very efficient. All measured production parameters: reproduction rate, number of piglets born alive, birth weight of piglets and number of piglets weaned per a litter improved after implementation of immunization program. Moreover, further improvement was observed with vaccination in the following reproduction cycles. The most spectacular effect of vaccination regarded average farrowing rate that increased from 64.76% in control group to 86.93% after basic vaccination. Two years after implementation of vaccination program this parameter reached 93.6%. Number of piglets weaned per sow per a litter improved from 10.31 to 11.74 after one year of vaccination and remained relatively stable through the following year. Simultaneously, the percentage of newborn piglets with birth weight < 1 kg decreased significantly (p < 0.05). To summarize, vaccination against PCV2 influenced positively the insemination rate, number of piglets born alive and weaned per litter as well as birth body weight and percentage of piglets weighing < 1 kg.     

上海地区引种地被石竹蒸腾特征及影响因子分析

采用Li-6400光合作用测定仪对在上海地区引种的地被石竹蒸腾速率日变化、季节变化特征进行研究.结果表明:(1)地被石竹蒸腾速率日变化为单峰型,峰值出现在11:00～12:00;蒸腾速率的季节变化为单峰曲线,6月份最高,达到12.72mmol·m2·s-1,11月份最低,仅为1.31mmol·m-2·s-1,生长季叶片平均值为6.07mmol·m-2·s1.(2)直接影响蒸腾速率日变化的主要因子春季(3月下旬)为光合有效辐射和相对湿度;夏季(6月下旬)为光合有效辐射和气温;秋季(10月初)为光合有效辐射、气温、胞间CO2浓度和相对湿度.(3)地被石竹三季单位叶面积平均H固碳量、日释氧量、日蒸腾释水量、日吸热量春季分别为12.16g·m-2·d1、8.85g·m-2·d-1、2480.89g·m2·d-1、6065.90KJ·m-2·d-1,夏季为12.46g·m-2·d1、9.07g·m-2·d-1、8283.25g·m-2·d-1、19940.75KJ·m2·d-1,秋季为10.29g·m-2·d-1、7.48g·m-2·d-1、2102.56g·m-2 ·d-1、5098.57KJ·m-2·d-1.     

密度对根蘖型苜蓿根系的影响

不同种植密度对根蘖性状的表现有影响,过分密植(100.00株/m~2)使得水平根减少,根蘖株率下降。单株根风干重与密度呈直线负相关;群体根风干重与其呈曲线回归。低、高密度的根量明显小于中密度。试验结果表明,根蘖型苜蓿的种植密度以25.00株/m~2左右为宜。     

青山羊泌乳期母羊的能量需要量研究

选用24只青山羊泌乳母羊,用饲养试验、消化代谢试验、比较屠宰试验及气体能量代谢试验等手段,研究其能量需要量。结果表明,在本试验条件下,试羊的能量表观消化率和代谢率分别为70.4％和85.0％,甲烷能占总能进食量(GEI)的9.20％。维持代谢能需要为502W~(0.75)KJ/天,每产一千克标准乳(FCM)需5060KJ泌乳代谢能。泌乳母羊的维持效率(K_m)为0.845,泌乳效率(K_1)为0.635,热增耗占GEI的14.34％。青山羊泌乳期母羊的代谢能总需要量(MERKJ/天)可按下式求得MER=502W~(0.75)+5060·FCM或:MER=502W~(0.75)+1.578NEL(式中:W~(0.75):kg;FCM:kg/天;NEL:kJ/天)。     

不同月份对母猪产仔及活仔率的影响

经11705窝(胎)次母猪各月份产仔和3733窝(胎)次母猪各月活产仔数的数理分析,其产仔数,活产率受不同月份气温、相对湿度等综合生态因子而影响;特别是8月份是母猪全年繁殖力最差的月份,8月份配种11月份产仔数最少,平均窝产13.66头;活产仔也是全年最低,平均12.75头;8月份活仔率87.09％,且一次情期受胎率为83.51％,都是全年最低的。     

Effects of energy supplementation on lamb production of Javanese thin-tail ewes

A 3-yr study was conducted in North Sumatra, Indonesia, as part of an evaluation of the feasibility of integrating sheep and rubber production. The objective was to evaluate the effects of increasing energy supplementation on reproduction and other performance criteria of Javanese Thin-Tail sheep grazing volunteer forages under 8- and 14-yr-old rubber trees. The control group was unsupplemented. The medium group was supplemented with high-energy feeds at 1% of the flock body weight, with the low and high groups receiving 60% or 140% of the daily energy provided by the medium group diet. Supplements provided 1.2 g protein per kilogram BW. There were 158 lambs born to the 152 ewes in the 1st year of the study. Preweaning mortality rates of lambs were reduced (P less than .01) with supplementation (45 vs 12, 3 and 12% for the control, low, medium and high groups, respectively). During the 3 yr, litter size was higher (P less than .01) in the high group (1.33, 1.31 and 1.34 vs 1.71 for ewes on the four respective diets). Observed repeatability of litter size of individual ewes in all treatment groups for the first three parities was higher (P less than .01) than would be expected if litter size were a random event. Of the lambs born in the 1st yr, kilograms of lamb weaned per ewe joined were 3.1, 7.8, 7.3 and 9.8. At prevailing prices, only the high supplement level was profitable compared to the control. For the high group, the added return from the sale of lambs born the 1st yr was 120% of the added cost of supplementing the ewes until all the lambs were weaned (15 mo). Response of sheep to the high level of energy supplementation, especially with regard to litter size, indicates that supplementing sheep grazing in rubber plantations at a high level can be profitable.     

A reduction in litter size on an ontario Swine farm

In a 200 sow herd, the litter size fell from an average of 10.5 pigs born alive per litter from January to June, to an average of 9.2 for the remainder of the year. Management changes during the first part of the year resulted in half the sows weaning litters at three weeks of age and half the sows weaning at four weeks of age instead of at six weeks as was previously done. The subsequent litter size was 9.3 pigs born alive per litter for three-week weaned sows compared to 10.0 for four-week weaning. The management of gilt breeding was also altered by the necessity to breed groups of 12 gilts in one-week periods of time and therefore a higher proportion of gilts may have been mated on their first estrus instead of their second or third estrus as had been the case. The difference in litter size of first parity sows between the first six months and the second six months was 1.1 pigs. Parvovirus infection may have been a factor contributing to the reduction in litter size amongst first parity sows; two groups of first parity sows experienced an increase in mummified piglets, a reduced far rowing rate, and smaller litter size. However, no attempt was made at diagnosing an infectious agent. Parity distribution remained relatively unchanged during the year and was not associated with the drop in litter size.