鸡静注,肌注及内服氟哌酸的药物动力学研究

选用４２只健康ＡＡ鸡，分３组（每组１４只）进行药物动力学研究：静注、肌注及内服的剂量均为１０ｍｇ／ｋｇ。用二氯甲烷提取血浆中的药物，反相高效液相色谱法测定血浆氟哌酸的浓度，测定时以吡哌酸为内标。所得药物一时间数据用ＭＣＰＫＰ计算机程序处理，静注给药拟合二室开放模型，主要动力学参数是：ｔ１／２α０．１４±０．０８ｈ，ｔ１／２β３．６５±１．０３ｈ，Ｋｅ０．８８±０．４０ｈ－１，Ｖｄ３．８１±０．９８Ｌ／ｋｇ，ＡＵＣ１４．１４±３．２９μｇ／ｍｌ．ｈ。内服和肌注给药均适合具有一级吸收二室开放模型，肌注的主要动力学参数是：ｔ１／２ｋａ０．２２±０．１０ｈ，ｔ１／２α１．０３±０．６５ｈ，ｔ１／２β６．８７±２．８６ｈ，Ｋｅ０．２８±０．１０ｈ－１，ＡＵＣ９．８６±２．８８μｇ／ｍｌ．ｈ，Ｆ６９．７８％。内服的主要动力学参数是：ｔ１／２ｋａ０．６９±０．２３ｈ，ｔ１／２α１．７６±０．８９ｈ，ｔ１／２β１０．４３±３．２２ｈ，Ｋｅ０．２１±０．０５ｈ－１，ＡＵＣ８．５６±１．３６μｇ／ｍｌ．ｈ，Ｆ６０．５２％。鸡静注、肌注、内服氟哌酸的药动学特征是吸收较快，在体内分布广泛、半衰期较长。     

恩诺沙星及其活性代谢物在鸡体内的药物动力学

为全面了解恩诺沙星在鸡体内的动力学过程与药效的关系进行了本研究。用反向高效液相色谱法测定鸡血浆中的药物质量浓度,所得恩诺沙星ｃｉ－ｔｉ数据用ＭＣＰＫＰ计算机程序处理,代谢物环丙沙星的ｃｉ－ｔｉ数据用代谢物动力学方法处理。静注恩诺沙星后的ｃｉ－ｔｉ数据符合二室开放模型,主要动力学参数：ｔ１／２α（０．２５±０．０４）ｈ,ｔ１／２β（５．２６±０．８１）ｈ,Ｖｄ（４．５３±１．０７）Ｌ／ｋｇ,ＣＬＢ（０．６１±０．１１）Ｌ／（ｋｇ·ｈ）,ＡＵＣ（１７．３９±３．９２）ｍｇ／（Ｌ·ｈ）。内服恩诺沙星的ｃｉ－ｔｉ数据,符合有吸收因素二室模型,主要动力学参数ｔ１／２ｋａ（０．４４±０．１１）ｈ,ｔ１／２α（１．１５±０．３８）ｈ,ｔ１／２β（９．１４±１．４５）ｈ,ＡＵＣ（１２．４８±２．３６）ｍｇ／（Ｌ·ｈ）,ｔｍａｘ（１．７７±０．２１）ｈ,Ｃｍａｘ（１．４４±０．３１）ｍｇ／Ｌ,Ｆ７２．１８％。试验结果表明,鸡静注与内服恩诺沙星后,代谢物环丙沙星的生成及消除缓慢、分布广泛,是影响恩诺沙星疗效的重要因素。     

克伦特罗在猪体内的生物利用度及药物动力学研究

６头体重４７．００±４．５７ｋｇ（Ｘ±Ｓ）的健康长白和大白杂交猪，拉丁方设计试验，按４ｍｇ／ｋｇ静注、肌注和内服克伦特罗，高效液相色谱法检测血浆中药物浓度，ＭＣＰＫＰ药代动力学程序处理药时数据。静注给药的药代动力学参数是：ｔ１／２α０．６２±０．１２ｈ，ｔ１／２β４．８７±１．５６ｈ，Ｖｄ（ａｒｅａ）４．４８±０．５６ｌ／ｋｇ，ＣｌＢ０．６３±０．１１ｌ／ｋｇ／ｈ，ＡＵＣ６．３９±１．２７μｇ／ｍｌ．ｈ。肌注给药的药动学参数是：ｔ１／２Ｋａ０．２２±０．１０ｈ，ｔ１／２α０．５６±０．２１ｈ，ｔ１／２β４．２５±１．１０ｈ，ｔｍａｘ０．６０±０．１３ｈ，Ｃｍａｘ１．２７±０．３５μｇ／ｍｌ，ＡＵＣ５．４８±１．２９μｇ／ｍｌ．ｈ，Ｆ８５．４０±４．６９％。内服给药的药动学参数是：ｔ１／２Ｋａ０．２８±０．１５ｈ，ｔ１／２Ｋｅ３．１５±０．３６ｈ，ｔｍａｘ１．４６±０．１９ｈ，Ｃｍａｘ０．６５±０．１３μｇ／ｍｌ，ＡＵＣ３．９３±０．９９ｍｇ／ｌ．ｈ，Ｆ６１．０２±１０．９０％。肌注给药的生物利用度与内服比较，差异极显著（Ｐ＜０．０１）。     

氧氟沙星在健康和霉形体与大肠杆菌感染鸡的药动学研究

本文报道氧氟沙星在健康和霉形体与大肠杆菌合并感染鸡体内的药动学研究,健康鸡单剂量内服氧氟沙星（１０ｍｇ／ｋｇ）其药－时数据符合一级吸收一室开放模型,主要动力学参数如下：ｔ１／２α为０．４７±０．２３ｈ,ｔ１／２β为５．９２±１．３４ｈ,ｔｍａｘ为１．８９±０．５２ｈ,Ｃｍａｘ为５．７９±１．０９μｇ／ｍＬ,ＡＵＣ为６０．９２±１７．００ｍｇ／Ｌ,ｈ,Ｔｃｐ（ｔｈｅｒ）为５９．０６±１４．２８ｈＦ,     

喹乙醇在鸡体内的毒物动力学及其生化毒性和病理学研究

本文对１３只健康ＡＡ鸡单次内服喹乙醇中毒剂量（１２０ｍｇ／ｋｇ）作了毒物动力学分析。用乙腈—乙酸乙酯混合溶剂提取血浆中的喹乙醇,反相高效液相色谱法（ＨＰＬＣ法）测定浓度。喹乙醇内服给药的药时数据适合一级吸收二室开放模型。毒物动力学主要参数为：ｔ１／２Ｋａ０．６３±０．２６ｈ,ｔ１／２α１．１２±０．３４ｈ,ｔ１／２β７．２６±３．０２ｈ,Ｋｅ０．５９±０．１５ｈ－１,Ｔｍａｘ１．１９±０．３１ｈ,Ｃｍａｘ７１．４０±１２．８１μｇ／ｍｌ,ＡＵＣ２５８．１２±３６．１１ｍｇ／Ｌ．ｈ。本试验表明,内服中毒剂量的喹乙醇在ＡＡ鸡体内的吸收、分布均很迅速,但消除缓慢;给药后２４ｈ,血药浓度均高于０．２μｇ／ｍｌ     

幼驹静注和口服恩诺沙星的药代动力学

恩诺沙星的药代动力学在成年马已有研究，但在小驹的药　动力学参数尚未见报道。本文研究了静注和口服恩诺沙星在幼驹体内的药物动力学。１　　材料和方法１．１　　动物５匹临床健康的幼驹。１～３周龄，体重４２～７７　ｋｇ，模拟　野外放牧条件，小驹可以自由进出河坝。１．２　　试验设计实验研究了先单剂量静注（５　ｍｇ／ｋｇ）恩诺沙星，７　～１０　ｄ后又单剂量口服（１０　ｍｇ／ｋｇ）恩诺沙星对幼驹的效果，再过７～１０　ｄ，对小驹以口服　恩诺沙星，连服８　ｄ，其中４只于最后一次给药２４　ｈ后处死。１．３　　测定方法…     

新生反刍动物血浆cAMP和cGMP水平变化初探

初步观察了６头黑白花犊牛和３只湖羊羔生后２４ｈ内血浆环腺苷酸（ｃＡＭＰ）和环鸟苷酸（ｃＧＭＰ）水平变化。结果表明：犊牛出生时ｃＡＭＰ和ｃＧＭＰ分别为１．１２±０．１０ｐＭ／ｍｌ和０．８７±０．０４ｐＭ／ｍｌ，羔羊生后１ｈ分别为１．２０±０．０１ｐＭ／ｍｌ和０．３９±０．０１ｐＭ／ｍｌ，在生后２～４ｈ内犊牛和羔羊ｃＡＭＰ和ｃＧＭＰ均呈上升趋势，以后在相对高水平波动直至２４ｈ，ｃＡＭＰ／ｃＧＭＰ比值生后较高，２ｈ内下降，以后处于较低的比值直至２４ｈ     

乐都驴血液生化参数测定

对青海省乐都县５１头驴的１３项血清（浆）生化参数进行测定，结果：总蛋白为７４．４±９．７ｇ／Ｌ，Ａ／Ｇ为Ｏ．９±０．２，总脂为２．５±０．６ｇ／Ｌ，胆固醇为２．５±０．９ｍｍｏｌ／Ｌ，Ｋ￣＋为４．５±０．５ｍｍｏｌ／Ｌ，Ｎａ￣＋为１３７±３ｍｍｏｌ／Ｌ，Ｃａ￣（２＋）为２．３±０．３ｍｍｏｌ／Ｌ，Ｍｇ￣（２＋）为１．６±０．４ｍｍｏｌ／Ｌ，无机磷为２．０±０．６ｍｍｏｌ／Ｌ，ＧＰＴ为８．４±６．４ＩＵ／Ｌ，ＧＯＴ为１１．６±９．７ＩＵ／Ｌ，血浆葡萄糖为５．６±０．５ｍｍｏｌ／Ｌ；上述参数在骟、母驴间无显著差异。     

氯霉素在草鱼和复合四倍体异育鲫体内的比较药代动力学

研究并比较了给草鱼和复合四倍体异育银鲫（简称高倍体鲫鱼）单次腹腔注射氯霉素１００ｍｇ／ｋｇ后的药代动力学特征。采用ＨＰＬＣ测定血液中氯霉素的浓度。试验期间水温为（２０±２）℃，结果表明，氯霉素在这２条鱼体内的处置过程相似，均可用于带一级吸收的二室开放模型进行描述，药物从腹腔吸收迅速，给药后分别在０．９２ｈ和０．６３ｈ血中浓度达到高峰，无吸收时滞，在草鱼和高倍体鲫鱼体内药物ｔ１／２ｐ相近，分别为１１     

部分家畜的血磷和血糖含量

用磷钼蓝法和邻甲苯胺法检测了青海省骡，驴，黑白花奶牛，猪，西德长毛兔的血清无机磷和血清葡萄糖含量，结果；骡为１．４９±０．２０ｍｍｏｌ／Ｌ，３．８９±０．６８ｍｏｌ／Ｌ，驴１．３９±０．２２ｍｍｏｌ／Ｌ，３．７２±０．５３ｍｍｏｌ／Ｌ，黑白花奶牛１．７１±０．４６ｍｍｏｌ／Ｌ３．５５±０．６３ｍｍｏｌ／Ｌ，猪２．３９±０．３４ｍｍｏｌ／Ｌ，４．２５±０．６５ｍｍｏｌ／Ｌ，西德长毛兔１．５６±０．４     

Feline intracranial neoplasia: retrospective review of 160 cases (1985-2001)

The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.     

The Prevalence and Intensity of Helminth and Coccidial Infections in Dairy Cattle in Central Kenya

A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Hypothalamic dopamine is required for salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the relationship between hypothalamic dopamine (DA) and salsolinol (SAL) for the secretion of prolactin (PRL) in goats. SAL or thyrotropin‐releasing hormone (TRH) was intravenously injected into female goats treated with or without the D₂ DA receptor antagonist haloperidol (Hal), which crosses the blood‐brain barrier, and the PRL‐releasing response to SAL was compared with that to TRH. PRL‐releasing responses to SAL, Hal, and Hal plus SAL were also examined after a pretreatment to augment central DA using carbidopa (Carbi) and L‐dopa. The PRL‐releasing response to Hal alone was greater than that to SAL or TRH alone. The PRL‐releasing response to Hal plus SAL was similar to that of Hal alone. In contrast, the PRL‐releasing response to Hal plus TRH was greater than that to TRH or Hal alone. The treatment with Carbi plus L‐dopa inhibited SAL‐ and Hal‐induced PRL secretion. The inhibition of the PRL‐releasing response to SAL disappeared when SAL was injected with Hal. These results indicate that the mechanisms underlying the SAL‐induced PRL response differ from those of TRH, and suggest that hypothalamic DA and its synthesis is associated in part with SAL‐induced PRL secretion in goats.     

Laboratory diagnosis of respiratory diseases of cattle

The authors describe the procedure of laboratory diagnosis for bovine respiratory diseases: direct diagnosis by isolation and for identification of bacteria or viruses and indirect diagnosis by serological methods. They specify the restraints and limits of this diagnosis and the significance results which are obtained and connected with knowledge of anamnestic information.     

The effect of peri-parturient anthelmintic treatment on the productivity of dairy cattle in subtropical western India

Trials with fenbendazole (Panacur, Hoechst India Ltd) were carried out on two commercial farms in subtropical western India to study the response and economics of nematode treatment in adult dairy cows. Milk yield, lactation length, time to first oestrus and worm egg output were monitored in treated and control groups. Treatment reduced the egg count considerably. Treated cows produced 142 litres more milk over 100 days (p<0.05), with extension of lactation length and advancement of time to first oestrus. The economic gain in terms of milk yield far outweighed the cost of anthelmintic used.