稀土甲壳素对生长肉猪的效应研究

稀土甲壳素对生长肉猪的效应研究顾振权（江苏省启东市科委２２６２００）宋锦昌（启东市农业局）前言稀土元素在农作物方面应用，经过“六五”的稀土农用技术攻关，取得了较好的效益。随着稀土在农业和医药方面的应用日益取得的成果，人们对稀土元素的生物效应进行了深入...     

鸡饲料中添加稀土化合物效果研究

<正> 稀土是镧系15种元素与钇、钪共17种金属元素的统称。由于这类元素具有特殊的活泼性而在冶金、电子、化工、光学、轻工等众多领域得到广泛应用。30年代以来,国外学者对稀土元素的生理活性曾做过一些研究。近20年,我国在稀土农用研究上有一系列突破,成功地将稀土应用于我国农业生产,为稀土的应用开辟了一个新领域。配合稀土农用进行的稀土毒理学研究,曾发现一些稀土元素对动物有一定的生理作用。80年代中后期陆续开始的稀土对畜、禽、鱼的作用研究都取得了可喜进展。本文报道的是稀土化合物应用于养鸡的研究结果。5年来通过小试、中试、示范试用等试验程序,肯定了稀土对肉仔鸡和产蛋鸡生产性能的影响,并确定了在饲料中的适宜添加剂量、饲喂方法及经济效益。     

稀土元素的肝脏蓄积性及毒性危害

综合论述了稀土元素在机体肝脏的蓄积性及其毒性效应,分析了稀土农业应用对生态环境和人群健康的危害。稀土元素被长期低剂量摄入,可在肝脏中蓄积,导致肝脏形态和病理组织变化、肝细胞损伤、肝代谢紊乱引起脂肪肝;高于2 mg.kg-1剂量的农用稀土(常乐)仍能通过胎盘屏障引起肝细胞和发育中的红细胞DNA损伤。     

稀土元素在反刍动物饲养中的应用

稀土元素是镧系元素与化学性质相似的钪、钇等17种元素的总称。稀土元素位于元素周期表中ⅢB族,因天然丰度低而得名。地壳中稀土元素占地壳重量的0.016%,植物体中稀土元素约占0.002%～0.003%,在人体中约占0.007%[1]。根据稀土的电子层结构、密度、化学、地理化学及矿物化学等性质上的区别,可划分为轻稀土和重稀土,而农用稀土主要是轻稀土。20世纪30年代以来,有关稀土在种植业及养殖业上的应用研究较多,取得了可喜的成果。我国稀土储量占世界总储量的76%,是世界上稀土资源最丰富的国家。如能在生产中大规模推广应用,将对降低成本,提高产品数…     

稀土元素在反刍动物饲养中的应用

稀土元素是镧系元素与化学性质相似的钪、钇等17种元素的总称。稀土元素位于元素周期表中ⅢB族,因天然丰度低而得名。地壳中稀土元素占地壳重量的0.016%,植物体中稀土元素约占0.002%￣0.003%,在人体中约占0.007%。根据稀土的电子层结构、密度、化学、地理化学及矿物化学等性质上的区别,可划分为轻稀土和重稀土,而农用稀土主要是轻稀土。20世纪30年代以来,有关稀土在种植业及养殖业上的应用研究较多,取得了可喜的成果。我国稀土储量占世界总储量的76%,是世界上稀土资源最丰富的国家。如能在生产中大规模推广应用,将对降低生产成本,提高产品…     

稀土元素的肝脏蓄积性及毒性危害

综合论述了稀土元素在机体肝脏的蓄积性及其毒性效应,分析了稀土农业应用对生态环境和人群健康的危害.稀土元素被长期低剂量摄入,可在肝脏中蓄积,导致肝脏形态和病理组织变化、肝细胞损伤、肝代谢紊乱引起脂肪肝;高于2 mg·kg-1剂量的农用稀土(常乐)仍能通过胎盘屏障引起肝细胞和发育中的红细胞DNA损伤.     

稀土元素在反刍动物饲养中的应用

稀土元素是镧系元素与化学性质相似的钪、钇等17种元素的总称。稀土元素位于元素周期表中ⅢB族，因天然丰度低而得名。地壳中稀土元素占地壳重量的0．016％，植物体中稀土元素约占0．002％～0．003％，在人体中约占0．007％。根据稀土的电子层结构、密度、化学、地理化学及矿物化学等性质上的区别，可划分为轻稀土和重稀土，而农用稀土主要是轻稀     

稀土元素在养殖业中的应用

稀土元素又称调系元素，包括原子序数从51到刀的润、韩等15种元素及性质极为相似的抗和化．依其性质上的微小差异，将其划分为星稀土和轻稀土。目前，应用于农业和养殖业生产中的为轻稀土。稀土元素的应用至今已有近百年的历史，已被广泛的应用于冶金、石油、化工、轻工、电子、农业等领域。自60年代以来，前苏联、美国、罗马尼亚、日本等国均先后有过将稀土元素用于养殖业的报道。我国是世界上稀土资源最丰富的国家，1972年开始稀土农用研究。经过“六·五”、“七·五”期间的全国性科技攻关，在稀土基础理论和应用研究上有了重大突破。稀…     

稀土在草地生产中的作用

稀土元素是化学元素周期表中的镧系元素和化学性质相似的17种元素的总称。大部分稀土金属元素如:镧La、铈Ce、镨Pr、钕Nd、钐Sm、铕Eu、钆Gd等的硝酸盐,具有肥效作用。按氧化物含量计算,每亩地只需几克到几十克,又广泛称为稀土微肥。使用稀土每亩成本只有0.20元左右,使用方便,效益显著,因此很适于推广应用。从本世纪三十年代开始,一些国家陆续开始了稀土对一些作物的刺激生长、增加结实与产量的农用研究工作。我国稀土资源极为丰富。自1972年以来,国内二十几个省市自治区的一些有关研究单位与院校对稀土的农用肥效作用也进行了研究。     

稀土对发酵血粉菌生长增殖的影响

稀土对发酵血粉菌生长增殖的影响河北省张家口农业高等专科学校闫贵龙内蒙古农牧学院王守清内蒙古农牧学院赵志恭内蒙古农牧学院王文元稀土元素在生物领域已经得到广泛的研究应用，适量的稀土可促进动物、植物生长和提高畜禽生产，但稀土对发酵血粉菌的作用如何未见报道。...     

稀土元素在动物营养上的应用

我国稀土资源丰富,其储量、开采量均居世界首位,已广泛应用于工业、农业等领域。稀土元素作为动物饲料添加剂,可以促进畜禽生长、减少死亡率、增强免疫等生理作用,在动物营养中应用的前景广阔。论述了稀土资源的分布、添加剂的种类、作用机理以及在动物营养中的应用做一综述。     

稀土的作用机理及饲用安全性

稀土元素在化学元素周期表中,为第6周期,属于镧系族及钪、钇共17种元素的总称。具有清除自由基、加速蛋白质合成、消炎镇痛、调节动物机体代谢等作用。近年来又发现在饲料中添加稀土,可以起到促进畜禽的生长性能、减少死亡率、调节免疫反应等生理作用,随着对稀土研究的深入,其在畜牧生产中的应用必将发挥积极的作用。     

混合稀土对小白鼠生长的影响

试验采用单因子设计,在相同基础日粮中分别添加0、25、50、75mg/kg的混合碳酸稀土组成4种日粮。20d的饲养试验结果表明,混合稀土能显著提高小白鼠的生长。与对照组相比,日粮中添加混合稀土能显著提高小白鼠的体增重(P<0.05)和采食量(P<0.05)。     

微肥、稀土对苜蓿产量和品质的影响

在土壤瘠薄、盐碱较重的地段研究微肥、稀土对苜蓿产量及品质的影响,结果表明:喷施微肥及稀土对苜蓿有明显增产作用,200 g/kg稀土液产量最高,为16 708.40 kg/hm2,比对照高24.74%;施肥后粗蛋白含量明显提高,100 g/kg稀土液效果最好,两茬分别为22.14%、23.30%,比对照提高35.99%、30.75%;喷施微肥及稀土可增加苜蓿种植的经济效益,200 g/kg稀土液,净增收1 979.52元/hm2。     

Health examinations and clinical diagnostic procedures of ratites.

It is important to remember when performing health examinations and clinical diagnostic procedures on ratites that all protocols mentioned in this article should be followed; this includes reviewing history, environmental evaluation, proper handling, complete hands-on physical examination, diagnostic testing, and postmortem examination. The individual ratite examination is becoming rare, but veterinarians and producers must remember that individual birds make up the flock. Flock health is maintained by diagnosing disease and health problems early in the most susceptible animals. The most successful producers will use veterinarians as a major element to their management program to raise the most desirable birds for the future of the industry.     

Annual meeting keynote address: Animal agriculture and emerging social ethics for animals

Businesses and professions must stay in accord with social ethics, or risk losing their autonomy. A major social ethical issue that has emerged in the past three decades is the treatment of animals in various areas of human use. This point can be illustrated with numerous examples across all areas of animal use. These examples reflect society's moral concern having outgrown the traditional ethic of animal cruelty that began in biblical times and is encoded in the laws of all civilized societies. There are five major reasons for this new social concern, most importantly, the replacement of husbandry-based agriculture with industrial agriculture. This loss of husbandry to industry has threatened the traditional fair contract between humans and animals, and resulted in significant amounts of animal suffering arising on four different fronts. Because such suffering is not occasioned by cruelty, a new ethic for animals was required to express social concerns. Since ethics proceed from preexisting ethics rather than ex nihilo, society has looked to its ethic for humans, appropriately modified, to find moral categories applicable to animals. This concept of legally encoded rights for animals has emerged as a plausible vehicle for reform. The meaning of this ethical movement for animal agriculture is examined. Animal agriculture should explore ways to replace the animal husbandry lost to industrialization.     

西藏草地畜牧业发展战略的调整

本文分析并提出西藏草地畜牧业发展战略调整应:从传统的纯牧区逐步向半农半牧区和农区过渡,形成牧区繁育,农区、半农半牧区育肥,城镇加工的分布格局;开发东部林芝地区草地载畜潜力,稳定、提高中部拉萨市、山南地区草地畜牧业的生产经营水平,保护西部那曲与阿里地区草地,划定禁牧区,建设西部自然保护区;建植人工草地,实施退耕还草、农田种草,实现以草定畜;在青藏铁路沿线,选择低海拔城镇,建设牦牛肉、肥羔肉小包装、分割肉加工基地,以此带动东部、中部绿色牦牛肉、肥羔肉生产和季节草地畜牧业的发展;建设西部绒山羊基地和"一江两河"流域奶牛业;努力扩大边境畜产品贸易,提高畜产品商品率.     

Validity of specifically applied rare earth elements and compartmental models for estimating flux of undigested plant tissue residues through the gastrointestinal tract of ruminants

The validity of using rare earth elements as flow markers of undigested residues was evaluated by comparing mean gastrointestinal residence time (GMRT) of rare earths specifically applied to cottonseed hulls (CSH) to that of the indigestible fiber of CSH. Feces were collected from five lambs fed a mineral supplemented diet of CSH containing 52 g CP/kg DM and five lambs fed a CSH plus cottonseed meal diet (CSH+CSM) containing 123 g CP/kg DM. Rare earth elements (La, Yb, and Tb) specifically bound to CSH were included in the diet for a 5-d period and then deleted from the diet for a 3-d period. Following the last fecal collection, lambs were slaughtered for collection of digesta from segments of the gastrointestinal tract. Potentially indigestible NDF (PIF) was determined in diets and digesta from each segment of the gastrointestinal tract. Mean turnover rate, time delay, and GMRT for each rare earth element was estimated by fitting an age-dependent compartment model to profiles of markers appearing in the feces (compartmental model-marker method, CMM). The GMRT also was computed by the indigestible entity pool dilution method (IEPD) as grams of PIF in sampled segment/mean intake rate of PIF proceeding slaughter, g/h. The GMRT computed by the CMM and the IEPD methods did not significantly (P < 0.05) differ (99.6 vs 94.8 h and 58.9 vs 59.5 h for CMM vs IEPD and CSH and CSH+CSM diets, respectively). Regression of GMRT estimated for rare earths vs PIF yielded a highly significant regression (P = 0.001) with a regression coefficient of 0.94 +/- 0.016. It was concluded that rare earth elements applied to specific feeds are valid flow markers for the undigested residues derived from such marked feeds.     

Heart rate measurements as an index of energy expenditure and energy balance in ruminants: a review

A major part of the ME consumed by ruminants (MEI) is dissipated as heat. This fraction, called heat production or energy expenditure (EE), is assayed largely by measuring O2 consumption (VO2). Conventional measurement of EE in controlled conditions in chambers does not reflect the complexity of natural, environmental, and social conditions of free-ranging animals. In mammals, most of the measured VO2 is transferred to the tissues through the heart; therefore, regression of heart rate (HR) against VO2 can be used to estimate the EE of free-ranging animals. The present article reviews the current knowledge on the use of HR for estimating EE. Energy expenditure can be determined from HR measurements, recorded daily over the course of several days, multiplied by the VO2 per beat. When an animal does not perform significant exercise, a constant value of VO2 per beat [O2 pulse (O2P)] measured over a short period (10 to 15 min) is used; during exercise, O2P increases, and the regression equation of VO2 against HR is used. Under extreme heat load, HR increases to improve heat dissipation, and O2P decreases; therefore, the effect of heat load on O2P needs to be taken into account. Cold stress that doubles heat production does not affect O2P. Heart rate and EE are highly correlated with MEI, but there is significant individual variation in the relationship; therefore, the daily change in the HR of individual animals can be used as an indicator of changes in the individual energy status of a ruminant, and the average HR of the group can serve in the estimation of the energy status of the group. When O2P is measured, the average group EE is an indication of the energy balance of the whole group. Because the MEI of nondraft animals is the sum of EE and retained energy (RE), the MEI of free-ranging ruminants can be determined by measurement of EE by the HR method and adding the RE. Similarly, the RE can be determined without slaughtering the animals from measurements of EE and MEI. Soon when devices for automatic HR monitoring of domestic ruminants become available at a reasonable price, continuous monitoring of HR might provide producers with a sensitive tool for identifying changes in the energy status of their animals. This will also significantly help to shorten the time needed to identify health problems of individual animals.