肉鸡发育障碍与矮小综合征

肉鸡发育障碍与矮小综合征是一种包括肠道损害等多症状的传染性疾病，目前已遍布世界各地，在蛋鸡、珍珠鸡和火鸡中均有发生，是一个严重威胁现代养禽业的重大问题。论文从肉鸡发育障碍与矮小综合征的临床症状、病理变化和病原学对其进行了综述，以期为本病的诊断和预防提供参考。     

Impact of variation in structure of condensed tannins from sainfoin (Onobrychis viciifolia) on in vitro ruminal methane production and fermentation characteristics

Our study investigated the effects of condensed tannins (CT) on rumen in vitro methane (CH₄) production and fermentation characteristics by incubating lucerne in buffered rumen fluid in combination with different CT extracts at 0 (control), 40, 80 and 120 g CT/kg of substrate DM. Condensed tannins were extracted from four sainfoin accessions: Rees ‘A’, CPI63763, Cotswold Common and CPI63767. Gas production (GP) was measured using a fully automated GP apparatus with CH₄ measured at distinct time points. Condensed tannins differed substantially in terms of polymer size and varied from 13 (Rees ‘A’) to 73 (CPI63767) mean degree of polymerization, but had relatively similar characteristics in terms of CT content, procyanidin: prodelphinidin (PC: PD) and cis:trans ratios. Compared to control, addition of CT from CPI63767 and CPI63763 at 80 and 120 g CT/kg of substrate DM reduced CH₄ by 43% and 65%, and by 23% and 57%, respectively, after 24‐h incubation. Similarly, CT from Rees ‘A’ and Cotswold Common reduced CH₄ by 26% and 46%, and by 28% and 46% respectively. Addition of increasing level of CT linearly reduced the maximum rates of GP and CH₄ production, and the estimated in vitro organic matter digestibility. There was a negative linear and quadratic (p < 0.01) relation between CT concentration and total volatile fatty acid (VFA) production. Inclusion of 80 and 120 g CT/kg of substrate DM reduced (p < 0.001) branched‐chain VFA production and acetate: propionate ratio and was lowest for CPI63767. A decrease in proteolytic activity as indirectly shown by a change in VFA composition favouring a shift towards propionate and reduction in branched‐chain VFA production varied with type of CT and was highest for CPI63767. In conclusion, these results suggest that tannin polymer size is an important factor affecting in vitro CH₄ production which may be linked to the CT interaction with dietary substrate or microbial cells.     

The Kinetic Study of Adsorption of Methane on Anthracite and Its Char

The adsorption quantities of methane on anthracite and its char at different tem-perature and time were measured by using volumetric niethod. The corresponding adsorption formula-is presented. The experimental results have shown that the diffusion acti-vation energies of methane in the anthracite and its char are 14.3 kJ/mol and 26. 3 kJ/mol.It issuggested that the diffusion process of methane could be the flow through the micropores in the an-thracite and its char.     

Effect of rice variety on methane emission from an Indonesian paddy field

Variations in CH₄ emission from a Sumatra paddy field in which 8 popular modern varieties in Indonesia were grown were compared in the 1994/1995 rainy season. Total amounts of CH₄ emitted during the period of rice growth were in the ranges of 32.6-41.7 and 51.3–64.6 g CH₄ m^-2 for the plots amended with chemical fertilizer only and those amended with both rice straw and chemical fertilizer, respectively. The mean CH₄ emission rate was highest in the plot with the variety Bengawan solo and lowest in the plots with the varieties Atomita-4 and Way seputih among the plots which received chemical fertilizer, while highest in the plot with Way seputih and lowest in the plot with Bengawan solo among the plots amended with both rice straw and chemical fertilizer. The increase in the mean CH₄ emission rates by rice straw application was higher for the plots planted with Way seputih (1.98 times) and Atomita-4 (1.77 times) than for the plots with Bengawan solo (1.23 times) and IR-64 (1.35 times). The plots with Walanai and Cisanggarung recorded intermediate mean emission rates and the increase in CH₄ emission by rice straw application was also intermediate (1.57–1.64 times). It was noteworthy that Way seputih and Atomita-4 were derived from the variety Cisadane, Bengawan solo and IR-64 from the variety IR-54, and Walanai and Cisanggarung from the varieties IR-36 and Pelita 1-1, respectively.

The amounts of CH. emitted for 1 kg grain production ranged from 53 (Atomita-4) to 74 (Kapuas and Walanai) and from 89-93 (IR-64, Bengawan solo, and Atomita-4) to 121 (Kapuas) g CH₄ kg^-1 of grain for the plots amended with chemical fertilizer and those amended with rice straw and chemical fertilizer, respectively.     

调控反刍家畜瘤胃甲烷生成的措施

本文通过对反刍家畜瘤胃甲烷气体生成机理及控制其产量的措施的概述,以求提供有效的方法,在不显著影响反刍家畜的生产性能的情况下达到减轻瘤胃甲烷排放对大气环境造成污染的目的。     

农村生态型沼气工程设计软件的开发

依据中国农村生态型沼气工程的应用对象和特点，选择庭院经济、生态温室、生态果园3种模式建立了数学模型并开发设计了辅助设计软件。该软件能依据用户的设计要求，经计算绘制整套的沼气工程设计施工图，并具有界面友好、简单易用的特点，同时采用视频形式详细介绍了沼气的施工与维护方法。     

南方低甲烷排放的高产水稻品种筛选与评价

为综合评价高产和低甲烷(CH4)排放兼具的水稻品种,应对我国粮食安全和环境保护问题,于2013年晚季和2014年早季,以南方稻区50个代表品种为供试材料,在盆栽条件下采用静态箱-气相色谱法测定品种的CH4排放通量,并对生育期的CH4排放量、稻谷产量及植株农艺性状进行了综合评价。结果表明,早、晚季供试品种间的CH4排放量和产量均存在显著差异。早季全生育期的CH4排放量在7.37～21.10 g·m-2之间,晚季分蘖期至幼穗分化期的CH4排放量在1.37～13.97 g·m-2之间;早季产量在0.40～0.65kg·m-2之间,晚季在0.59～0.87 kg·m-2之间。根据系统聚类法的分析结果,将供试品种划分成具有不同CH4排放量和产量水平的类型,从中筛选出了适合推广应用的CH4低排高产、中排高产和低排中产品种,如黄华占、五优308、丰华占、特三矮、茉莉占选、广超丝苗、珍桂矮、广恢998和七桂早25等。其中,恢复系广恢998组配品种、黄华占和五优308已在我国南方稻区大面积推广应用。相关分析结果表明,株高、叶面积指数与CH4排放通量呈显著正相关,这2个性状可作为高产低CH4排放水稻新品种选育的辅助筛选指标。此外,稻谷产量与CH4排放量无显著相关。研究结果为培育高产与低CH4排放兼具的新品种提供了亲本材料和理论依据。     

白洋淀湖心岛分散式鸭养殖污染控制技术研究

白洋淀分散鸭养殖产生的污染物是导致其水体污染的主要来源之一。依据“减量化、就地处置资源化、养分循环”思路,提出湖心岛分散鸭养殖污染控制模式,主要包括：鸭粪收集系统（收集网、径流和冲洗水收集沟）、鸭粪沼气发酵与利用系统、沼液湿地净化和沼渣利用系统。选择安新县安新镇王家寨村占地5 000 m2养殖1 500只鸭的湖心岛建立综合控制示范工程。2010年4~11月,示范工程在典型降雨日和非降雨日排水的COD、总氮、总磷分别为351 mg/L、74.2 mg/L、7.1 mg/L和214 mg/L、42.1 mg/L、5.3 mg/L,水质符合《畜禽养殖业污染物排放标准》（GB 18596-2001）;这是由于源头收集系统收集了陆上活动区40%的鸭粪,同时末端处理系统（沉淀池+人工湿地）对养鸭废水污染物的高效削减。沼气池产生的沼气和剩余的沼液沼渣可以作为能源和肥料加以利用。本文集成湖心岛分散鸭养殖污染控制模式简便、适用,具有推广价值。     

The use of a real-time PCR primer/probe set to observe infectivity of Yersinia ruckeri in Chinook salmon, Oncorhynchus tshawytscha (Walbaum), and steelhead trout, Oncorhynchus mykiss (Walbaum)

Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM), a common pathogen affecting aquaculture facilities and implicated in large losses of cultured fish. Fisheries scientists continue to gain a greater understanding of the disease and the pathogen by investigating methods of identification and pre- and post-infection treatment. In this study, a real-time PCR probe set for Y. ruckeri was developed to detect daily changes in the bacterial load during pathogen challenges. Two species of fish, Chinook salmon, Oncorhynchus tshawytscha, and steelhead trout, Oncorhynchus mykiss, were exposed to two strains of Y. ruckeri (Hag and SC) during bath challenges. A subset of fish was killed daily for 14 days, and the kidney tissue was biopsied to enumerate copies of pathogen DNA per gram of tissue. While Chinook exposed to either the Hag or SC strains exhibited similar pathogen loads, those exposed to the Hag strain displayed higher mortality (～66%) than fish exposed to the SC strain (～24% mortality). Steelhead exposed to the Hag strain exhibited a greater pathogen load and higher mortality (～42%) than those exposed to the SC strain (<1% mortality). Steelhead challenged with either strain showed lower pathogen loads than Chinook. The study illustrates the efficacy of the probe set to enumerate Y. ruckeri bacterial growth in the kidneys of fish. Also, strains of Y. ruckeri display species-specific growth patterns that result in differential mortality and pathogen load.     

Effects of illite supplementation on in vitro and in vivo rumen fermentation,microbial population and methane emission of Hanwoo steers fed high concentrate diets

This study was conducted to evaluate the effects of feeding supplemental illite to Hanwoo steers on methane (CH₄) emission and rumen fermentation parameters. An in vitro ruminal fermentation technique was conducted using a commercial concentrate as substrate and illite was added at different concentrations as treatments: 0%, 0.5%, 1.0%, and 2.0% illite. Total volatile fatty acids (VFA) were different (P < 0.05) at 24 h of incubation where the highest total VFA was observed at 1.0% of illite. Conversely, lowest CH₄ production (P < 0.01) was found at 1.0% of illite. In the in vivo experiment, two diets were provided, without illite and with addition of 1% illite. An automated head chamber (GreenFeed) system was used to measure enteric CH₄ production. Cattle received illite supplemented feed increased (P < 0.05) total VFA concentrations in the rumen compared with those fed control. Feeding illite numerically decreased CH₄ production (g/day) and yield (g/kg dry matter intake). Rumen microbial population analysis indicated that the population of total bacteria, protozoa and methanogens were lower (P < 0.05) for illite compared with the control. Accordingly, overall results suggested that feeding a diet supplemented with 1% illite can have positive effects on feed fermentation in the rumen and enteric CH₄ mitigation in beef cattle.