Sickness behavior, its mechanisms and significance

Recent studies have begun to clarify the pathogenesis of sickness behavior. Cytokines released by macrophages, dendritic cells and mast cells act on the brain to trigger behavioral changes in infected animals. The major cytokines, interleukin-1, tumor necrosis factor alpha, and others, all act on the hypothalamus to provoke alterations in the normal homeostatic condition. These include elevated body temperature, increased sleep, and loss of appetite as well as major alterations in lipid and protein metabolism leading to significant weight loss. Some of these changes are clearly directed towards enhancing the normal immune responses. The benefits of others such as appetite loss are unclear. It is also important to recognize that other animals may recognize sickness behavior as a sign of weakness and mark the victim out for targeting by predators. As a result, some prey species may work very hard to mask their sickness, a response that serves to complicate veterinary diagnosis.     

Pharmacokinetics of tramadol, and its metabolite O-desmethyl-tramadol, in cats

Tramadol is an analgesic agent and is used in dogs and cats. Tramadol exerts its action through interactions with opioid, serotonin and adrenergic receptors. The opioid effect of tramadol is believed to be, at least in part, related to its metabolite, O-desmethyl-tramadol. The pharmacokinetics of tramadol and O-desmethyl-tramadol were examined after intravenous (i.v.) and oral administration of tramadol to six cats. A two-compartment model (with first-order absorption in the central compartment for the oral administration) with elimination from the central compartment best described the disposition of tramadol in cats. After i.v. administration, the apparent volume of distribution of the central compartment, the apparent volume of distribution at steady-state, the clearance, and the terminal half-life (mean +/- SEM) were 1553+/-118 mL/kg, 3103+/-132 mL/kg, 20.8+/-3.2 mL/min/kg, and 134+/-18 min, respectively. Systemic availability and terminal half-life after oral administration were 93+/-7% and 204+/-8 min, respectively. O-desmethyl-tramadol rapidly appeared in plasma following tramadol administration and had terminal half-lives of 261+/-28 and 289+/-19 min after i.v. and oral tramadol administration, respectively. The rate of formation of O-desmethyl-tramadol estimated from a model including both tramadol and O-desmethyl-tramadol was 0.014+/-0.003/min and 0.004+/-0.0008/min after i.v. and oral tramadol administration, respectively.     

那西肽的饲用性质及其应用

那西肽是含硫多肽类抗生素，能阻碍细菌蛋白质的合成，促进畜禽生长，提高饲料效率，在肠道内不易被吸收，排出体外可迅速分解，具有无残留、与其他抗生素相互作用、无交叉耐药性和对环境影响小等特点。     

Arginine metabolism and its functions in growth,nutrient utilization,and immunonutrition of fish

Fish have limited ability in endogenous biosynthesis of arginine. Arginine is an indispensable amino acid for fish, and the arginine requirement varies with fish species and fish size. Recent studies on fish have demonstrated that arginine influences nutrient metabolism, stimulates insulin release, is involved in nonspecific immune responses and antioxidant responses, and elevates disease resistance. Specifically, arginine can regulate energy homeostasis via modulating the adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway, and also regulate protein synthesis via activating the target of rapamycin (TOR) signaling pathway. The present article reviews pertinent knowledge of arginine in fish, including dietary quantitative requirements, endogenous anabolism and catabolism, regulation of the endocrine and metabolic systems, and immune-regulatory functions under pathogenic challenge. Our findings showed that further data about the distribution of arginine after intake into specific cells, its sub-cellular sensor to initiate downstream signaling pathways, and its effects on fish mucosal immunity, especially the adaptive immune response against pathogenic infection in different species, are urgently needed.     

Progress in the capture, manipulation, and delivery of medical media and its impact on education, clinical care, and research

In this article, advances in the application of medical media to education, clinical care, and research are explored and illustrated with examples, and their future potential is discussed. Impact is framed in terms of the Sloan Consortium's five pillars of quality education: access; student and faculty satisfaction; learning effectiveness; and cost effectiveness. (Hiltz SR, Zhang Y, Turoff M. Studies of effectiveness of learning networks. In Bourne J, Moore J, ed. Elements of Quality Online Education. Needham, MA: Sloan-Consortium, 2002:15-45). The alternatives for converting analog media (text, photos, graphics, sound, video, animations, radiographs) to digital media and direct digital capture are covered, as are options for storing, manipulating, retrieving, and sharing digital collections. Diagnostic imaging is given particular attention, clarifying the difference between computerized radiography and digital radiography and explaining the accepted standard (DICOM) and the advantages of Web PACS. Some novel research applications of medical media are presented.     

Pharmacokinetics of florfenicol and its metabolite, florfenicol amine, in dogs

A study on the bioavailability and pharmacokinetics of florfenicol was conducted in six healthy dogs following a single intravenous (i.v.) or oral (p.o.) dose of 20 mg kg(-1) body weight (b.w.). Florfenicol concentrations in serum were determined by a high-performance liquid chromatography/mass spectrometry. Plasma concentration-time data after p.o. or i.v. administration were analyzed by a non-compartmental analysis. Following i.v. injection, the total body clearance was 1.03 (0.49) L kg(-1)h(-1) and the volume of distribution at steady-state was 1.45 (0.82) L kg(-1). Florfenicol was rapidly distributed and eliminated following i.v. injection with 1.11 (0.94)h of the elimination half-life. After oral administration, the calculated mean C(max) values (6.18 microg ml(-1)) were reached at 0.94 h in dogs. The elimination half-life of florfenicol was 1.24 (0.64) h and the absolute bioavailability (F) was achieved 95.43 (11.60)% after oral administration of florfenicol. Florfenicol amine, the major metabolite of florfenicol, was detected in all dogs after i.v. and p.o. administrations.     

Hemoconcentration in calves and its relation to the hematologic, protein, mineral and electrolyte profile

The dynamics of hematological, protein, mineral and electrolytic profile was examined clinically in nine calves when the hemoconcentration was induced experimentally. The hemoconcentration occurred after diarrhea caused by the per os application of 12 g saccharose per one kg of live weight. The hemoconcentration culminated six hours after application. The calves where the hemoconcentration did not exceed the critical value were included in the first group, and the calves with the extreme hemoconcentration values in the other group. In the first group (with the increasing hemoconcentration degree), a statistically significant increase was found in the values of hematocrit, erythrocytes, hemoglobin, total protein in blood serum and total immunoglobins and a statistically insignificant increase in the levels of leucocytes, inorganic phosphorus, serum calcium and sodium. Serum potassium and magnesium showed the inverse dynamics, i. e. the decrease. In the second group (with the extreme hemoconcentration), hyperkalemia and slight hypermagnesemia were identified, while the other parameters showed deviations similar to those observed in the first group. After the rehydration of animals by a preparation without any influence on the studied parameters, the hemoconcentration and the parameters under study stabilized, while in the second group the hemoconcentration was increasing even during the rehydration and the levels of serum potassium and magnesium showed different tendencies. As follows from the results, in the calves suffering from scours accompanied by hemoconcentration the correction of the parameters of metabolic profile is necessary.     

家蚕核糖体的提取及其Sarcin/Ricin结构域的初步鉴定

用超速离心结合密度梯度离心法从蚕蛹中提取家蚕80S核糖体,经尿素变性聚丙烯酰胺凝胶电泳,结果表明家蚕核糖体的RNA同大鼠核糖体RNA在序列长度上有明显差异,家蚕5.8S rRNA高于大鼠5.8S rRNA,而家蚕5S rRNA的序列长度则略低于大鼠。用核糖体失活蛋白R ic in分析鉴定家蚕核糖体的Sarc in/R ic in结构域,结果是家蚕Sarc in/R ic in结构域比大鼠Sarc in/R ic in结构域离28S rRNA的3′末端更近。     

福建漳江口水鸟资源与保护对策

2003年1月至2006年3月，对福建漳江口红树林国家级自然保护区水鸟资源进行了调查，共发现水鸟33种（亚种）8442只，其中小白鹭、绿翅鸭、红嘴鸥数量是本调查期所调查到数量最多的3种水鸟，分别占调查总数的16．5％、23．5％和10．0％。另外，冬候鸟是本保护区水鸟中占优势的生态类群。随着保护区滩涂的高利用率，使水鸟食物种类及数量急剧减少，从而严重影响水鸟的栖息生存。因此，加强对保护区规范建设、科学管理和充分协调保护与利用之间的关系至关重要。     

Disposition, elimination, and bioavailability of phenytoin and its major metabolite in horses

OBJECTIVE: To determine pharmacokinetics and excretion of phenytoin in horses. ANIMALS: 6 adult horses. PROCEDURE: Using a crossover design, phenytoin was administered (8.8 mg/kg of body weight, IV and PO) to 6 horses to determine bioavailability (F). Phenytoin also was administered orally twice daily for 5 days to those same 6 horses to determine steady-state concentrations and excretion patterns. Blood and urine samples were collected for analysis. RESULTS: Mean (+/- SD) elimination half-life following a single IV or PO administration was 12.6+/-2.8 and 13.9+/-6.3 hours, respectively, and was 11.2+/-4.0 hours following twice-daily administration for 5 days. Values for F ranged from 14.5 to 84.7%. Mean peak plasma concentration (Cmax) following single oral administration was 1.8+/-0.68 microg/ml. Steady-state plasma concentrations following twice-daily administration for 5 days was 4.0+/-1.8 microg/ml. Of the 12.0+/-5.4% of the drug excreted during the 36-hour collection period, 0.78+/-0.39% was the parent drug phenytoin, and 11.2+/-5.3% was 5-(phydroxyphenyl)-5-phenylhydantoin (p-HPPH). Following twice-daily administration for 5 days, phenytoin was quantified in plasma and urine for up to 72 and 96 hours, respectively, and p-HPPH was quantified in urine for up to 144 hours after administration. This excretion pattern was not consistent in all horses. CONCLUSIONS AND CLINICAL RELEVANCE: Variability in F, terminal elimination-phase half-life, and Cmax following single or multiple oral administration of phenytoin was considerable. This variability makes it difficult to predict plasma concentrations in horses after phenytoin administration.     

广西港北区草地资源及其开发利用

论述了广西港北区划地资源的类型、数量、分布、载畜能力和利用现状，分析了存在的主要问题，提出了合理开发利用的措施。     

桑树四倍体的诱导及其应用

采用物理的辐射处理 ,化学的秋水仙碱处理和生物的杂交等技术方法 ,培育出桑四倍体材料 98份。其中用杂种实生幼苗秋水仙碱诱导的四倍体中 ,有些有较高的产叶量 ,可直接应用于生产 ;而大多数人工诱导的桑四倍体 ,则用作培育三倍体的亲本。诱导和利用人工四倍体资源 ,与二倍体桑杂交 ,以及无性固定三倍体或配制三倍体杂优组合 ,仍是桑树多倍体育种的主攻方向。     

Genome of Mycoplasma haemofelis, unraveling its strategies for survival and persistence

ABSTRACT: Mycoplasma haemofelis is a mycoplasmal pathogen (hemoplasma) that attaches to the host's erythrocytes. Distributed worldwide, it has a significant impact on the health of cats causing acute disease and, despite treatment, establishing chronic infection. It might also have a role as a zoonotic agent, especially in immunocompromised patients. Whole genome sequencing and analyses of M. haemofelis strain Ohio2 was undertaken as a step toward understanding its survival and persistence. Metabolic pathways are reduced, relying on the host to supply many of the nutrients and metabolites needed for survival. M. haemofelis must import glucose for ATP generation and ribose derivates for RNA/DNA synthesis. Hypoxanthine, adenine, guanine, uracil and CMP are scavenged from the environment to support purine and pyrimidine synthesis. In addition, nicotinamide, amino acids and any vitamins needed for growth, must be acquired from its environment. The core proteome of M. haemofelis contains an abundance of paralogous gene families, corresponding to 70.6% of all the CDSs. This "paralog pool" is a rich source of different antigenic epitopes that can be varied to elude the host's immune system and establish chronic infection. M. haemofelis also appears to be capable of phase variation, which is particularly relevant to the cyclic bacteremia and persistence, characteristics of the infection in the cat. The data generated herein should be of great use for understanding the mechanisms of M. haemofelis infection. Further, it will provide new insights into its pathogenicity and clues needed to formulate media to support the in vitro cultivation of M. haemofelis.     

Pharmacokinetics of florfenicol and its major metabolite, florfenicol amine, in rabbits

The pharmacokinetics of florfenicol and its active metabolite florfenicol amine were investigated in rabbits after a single intravenous (i.v.) and oral (p.o.) administration of florfenicol at 20 mg/kg bodyweight. The plasma concentrations of florfenicol and florfenicol amine were determined simultaneously by an LC/MS method. After i.v. injection, the terminal half-life (t(1/2lambdaz)), steady-state volume of distribution, total body clearance and mean residence time of florfenicol were 0.90 +/- 0.20 h, 0.94 +/- 0.19 L/kg, 0.63 +/- 0.06 L/h/kg and 1.50 +/- 0.34 h respectively. The peak concentrations (C(max)) of florfenicol (7.96 +/- 2.75 microg/mL) after p.o. administration were observed at 0.90 +/- 0.38 h. The t(1/2lambdaz) and p.o. bioavailability of florfenicol were 1.42 +/- 0.56 h and 76.23 +/- 12.02% respectively. Florfenicol amine was detected in all rabbits after i.v. and p.o. administration. After i.v. and p.o. administration of florfenicol, the observed Cmax values of florfenicol amine (5.06 +/- 1.79 and 3.38 +/- 0.97 microg/mL) were reached at 0.88 +/- 0.78 and 2.10 +/- 1.08 h respectively. Florfenicol amine was eliminated with an elimination half-life of 1.84 +/- 0.17 and 2.35 +/- 0.94 h after i.v. and p.o. administration respectively.     

Karyotyping, red blood cell and haemoglobin typing of the mithun (Bos frontalis), its wild ancestor and its hybrids

In Bhutan in remote parts of the Himalayas the mithun (Bos frontalis) has been used probably for centuries in an ingenious system for crossbreeding with domestic cattle which results in highly profitable hybrid females. The hybrid males are infertile and so far no stable crossbreed has been developed. Genetic analyses reported in this paper support the view that the gaur is the wild ancestor of the mithun. Both have only 58 chromosomes in contrast to 60 in cattle and also different, hitherto undescribed haemoglobins and blood groups which would justify the revision of the present classification of the subfamily Bovinae. If, with the aid of modern genetic methods, a stable crossbreed could be developed, dairy and beef production in Bhutan and many climatically similar areas could benefit greatly. Because of its remarkable size the mithun may, in the hands of enterprising breeders, also make a useful genetic contribution to beef production elsewhere.     

Pharmacokinetics of monepantel and its sulfone metabolite, monepantel sulfone, after intravenous and oral administration in sheep

The pharmacokinetic properties of the developmental Amino-Acetonitrile Derivative (AAD), monepantel and its sulfone metabolite, monepantel sulfone were investigated in sheep following intravenous (i.v.) and oral administrations. The sulfone metabolite was rapidly formed and predominated over monepantel 4 h after dosing, irrespective of the route of administration. The steady-state volume of distribution, total body clearance and mean residence time of monepantel were 7.4 L/kg, 1.49 L/(kg·h) and 4.9 h, respectively and 31.2 L/kg, 0.28 L/(kg·h) and 111 h, respectively for monepantel sulfone. The overall bioavailability of monepantel was 31%, but it was demonstrated that approximately the same amount of monepantel sulfone was produced whether monepantel was given intravenously or orally ( AUC _(0–∞) oral/ AUC _(0–∞) i.v. of 94% for monepantel sulfone), making oral administration a very efficient route of administration for monepantel in terms of the amount of sulfone metabolite generated. Because monepantel sulfone is the main chemical entity present in sheep blood after monepantel administration and because it is also an active metabolite, its pharmacokinetic properties are of primary importance for the interpretation of future residue and efficacy studies. Overall, these pharmacokinetic data aid in the evaluation of monepantel as an oral anthelmintic in sheep.     

An overview of aflatoxicosis of poultry: its characteristics, prevention and reduction

Aflatoxicosis represents one of the serious diseases of poultry, livestock and other animals. The cause of this disease in poultry and other food-producing animals has been attributed to the ingestion of various feeds contaminated with A. flavus. This toxigenic fungus is known to produce a group of extremely toxic metabolites, of which aflatoxin B1 (AFB1) is most potent. Avian species especially chicks, goslings, ducklings and turkey poults are most susceptible to AFB1 toxicity. The toxic effects of AFB1 are mainly localized in liver as manifested by hepatic necrosis, bile duct proliferation, icterus and hemorrhage. Chronic toxicity in those birds is characterized by loss of weight, decline in feed efficiency, drop in egg production and increased susceptibility to infections. The incidence of hepatocellular tumors, particularly in ducklings, is considered to be one of the serious consequences of aflatoxicosis. Even though prevention and avoidance are the best way to control aflatoxicosis, natural contamination of crops with A. flavus is sometimes unavoidable. Such aflatoxin-contaminated feeds can be decontaminated using various methods which mainly focus on physical removal or chemical inactivation of the toxins in the feeds. Moreover, dietary additives such as activated charcoal, phenobarbital, cysteine, glutathione, betacarotene, fisetin and selenium have also been reported to be effective in the reduction of aflatoxicosis in poultry.     

Intensity-modulated radiation therapy and helical tomotherapy: its origin, benefits, and potential applications in veterinary medicine.

Intensity-modulated radiation therapy (IMRT), especially image-guided IMRT as represented by helical tomotherapy, is a novel approach to therapy and is rapidly evolving. Both of these forms of therapy aim to allow targeted radiation delivery to the tumor volume while minimizing dose to the surrounding normal tissues. Adaptive radiation therapy and conformal avoidance are possible with intensity-modulated therapy and helical tomotherapy, which offer opportunities for improved local tumor control, decreased normal tissue toxicity, and improved survival and quality of life. Human and veterinary patients are likely to benefit from the continued development of this radiation delivery technique, and data over the next several years should be crucial in determining its true benefit.