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1.
Study was made of the pharmacokinetics and toxicopathy of deoxynivalenol (DON, vomitoxin) given IV to swine. In the 24 hours after swine were given DON, clinical signs of vomiting, diarrhea, muscular weakness, tremors, and twilight coma were similar to those observed with other 12,13-epoxytrichothecenes. Hypoglycemia and pancreatic islet cell lesions were observed which indicated that DON-induced changes in intermediary metabolism may be an insidious aspect of DON intoxication. Histopathologic examination of all organ systems revealed pancreatic acinar and islet cell necrosis and mild lympholysis of the mesenteric lymph nodes. The renal excretion of DON was altered by IV infusion of saline solution. Pharmacokinetic findings may indicate that DON was both secreted and reabsorbed by the renal tubules. The half-life of DON ranged from 2.08 to 3.65 hours. Residues of DON were not found in skeletal muscle of swine at 24 hours after dosing.  相似文献   

2.
正上期回顾:上一期介绍了呕吐毒素对营养素肠道吸收、对肠道通透性的影响和对紧密连接蛋白表达及其mRNA转录的影响。2.7呕吐毒素对肠道固有免疫反应的影响很早就发现局部免疫细胞,尤其是肠道相关免疫系统中的免疫细胞对肠道中呕吐毒素的暴露非常敏感,根据暴露的剂量、频度和时间不同,可引起免疫刺激或免疫抑制效果。据报道,在啮齿动物模  相似文献   

3.
王运亨 《中国乳业》2002,(11):18-19
奶牛实用养殖技术系列讲座 一、农民在选择饲养奶牛前应注意的几个问题二、奶牛的品种特征三、奶牛的行为习性四、奶牛的饲料种类五、奶牛的营养需要六、奶牛的日粮配合七、奶牛的饲养管理八、奶牛的繁殖管理九、奶牛的疾病防治十、影响奶牛产奶量及原料奶质量的主要因素  相似文献   

4.
Animal manure can be a source of antibiotic-resistant genes (ARGs) and pharmaceutical residues; however, few studies have evaluated the presence of ARG in pasture-raised animal production systems. The objective of this study was to examine changes in microbiome diversity and the presence of antibiotic residues (ABRs) on three farms that contained a diverse range of animal species: pasture-raised poultry (broiler and layer), swine, and beef cattle. Total bacterial communities were determined using 16S rRNA microbiome analysis, while specific ARGs (sulfonamide [Sul; Sul1] and tetracycline [Tet; TetA]) were enumerated by qPCR (real-time PCR). Results indicated that the ARG abundances (Sul1 [P < 0.05] and TetA [P < 0.001]) were higher in layer hen manures (16.5 × 10−4 and 1.4 × 10−4 µg kg−1, respectively) followed by broiler chickens (2.9 × 10−4 and 1.7 × 10−4 µg kg−1, respectively), swine (0.22 × 10−4 and 0.20 × 10−4 µg kg−1, respectively) and beef cattle (0.19 × 10−4 and 0.02 × 10−4 µg kg−1, respectively). Average fecal TetA ABR tended to be greater (P = 0.09) for broiler chickens (11.4 µg kg−1) than for other animal species (1.8 to 0.06 µg kg−1), while chlortetracycline, lincomycin, and oxytetracycline ABRs were similar among animal species. Furthermore, fecal microbial richness and abundances differed significantly (P < 0.01) both among farms and specific species of animal. This study indicated that the microbial diversity, ABR, ARG concentrations, and types in feces varied from farm-to-farm and from animal species-to-animal species. Future studies are necessary to perform detailed investigations of the horizontal transfer mechanism of antibiotic-resistant microorganisms (ARMs) and ARG.  相似文献   

5.
The reproductive performance of dairy animals is influenced by several factors, and accumulating lines of evidence indicate that mastitis is one of the determinants. Most of the published information relating mastitis with reproduction has evolved based on retrospective approach rather than controlled clinical studies. The complex nature of both mastitis and reproduction could be a limiting factor for understanding their relationship in detail. In this review, we analyzed the available retrospective studies on the effects of clinical mastitis on reproductive function and explained the possible mechanisms by which mastitis affects reproduction in dairy animals.  相似文献   

6.
Levels of arsenic, cadmium, copper, mercury and lead were determined in approximately 650 samples of liver and kidney from cattle, swine and poultry slaughtered in Canada during 1979-81. In addition zinc levels were determined in livers and kidneys from swine, and selenium and zinc levels were determined in the livers and kidneys from cattle. Depending on the element several methods of atomic absorption spectroscopy were used to analyze samples including flame, hydride generation, cold vapour generation and graphite furnace atomization. Analyses were also done by plasma emission spectroscopy. Levels of arsenic over 2.0 micrograms/g were detected in 0.9% of swine livers and 0.3% of swine kidneys. Cadmium levels higher than 1.0 micrograms/g were detected in 0.3% of cattle livers, 10.8% of cattle kidneys, 1.8% of swine kidneys, 0.4% of poultry livers and 0.3% of poultry kidneys. Levels of copper over 150 micrograms/g were detected in 0.4% of cattle and swine livers. Levels of lead over 2.0 micrograms/g were detected in 1.4% of poultry livers and 1.6% of poultry kidneys. The highest level of mercury detected in all species was 0.25 micrograms/g and the highest level of selenium was 1.9 micrograms/g. Zinc levels of over 100 micrograms/g were detected in 1.7% of cattle livers, 0.2% of cattle kidneys and 5.0% of swine livers.  相似文献   

7.
8.
The effect of three wheat grain treatments on the zootechnical performance (feed intake, milk production and milk fat and protein production) of dairy cattle was studied with 18 Holstein cows in each of two feeding trials (both a 3 × 3 Latin square design). Rolled wheat, NaOH treated wheat and immature wheat ensiled with Graintona-Plus (Vee-lik, Zuienkerke, Belgium) were compared in a ration with fixed DM proportions of wheat, maize silage and prewilted grass silage. The nutritive value of the three wheat treatments was derived from in situ rumen degradability studies and from in vivo digestibility experiments.

In situ rumen incubations showed that NaOH treatment strongly decreased protein and starch degradability of the wheat. Due to that importantly decreased starch degradability NaOH treated wheat may be a source of starch with a reduced risk of rumen acidosis as compared to rolled wheat. On the other hand, due to the ensiling, immature wheat had a very high washable starch fraction, despite the Graintona-Plus treatment. The protein value differed importantly, with the DPI (true protein digested in the small intestine; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value being 103, 125 and 76 g/kg DM for rolled, NaOH treated and ensiled wheat, respectively. The RDPB (degraded protein balance; [Tamminga, S., van Straalen, W.M., Subnel, A.P.J., Meijer, R.G.M., Steg, A., Wever, C.J.G., Blok, M.C., 1994. The Dutch protein evaluation system: the DVE/OEB-system. Livest. Prod. Sci. 40, 139–155]) value of the NaOH treated wheat was − 51 vs. − 37 and− 33 g/kg DM for rolled and ensiled wheat. In vivo digestibility trials with Holstein cows indicated that the net energy value of the wheat treatments was not significantly different.

In Trial 1, all diets were formulated to supply 105% of the requirements of DPI and net energy lactation (NEL; [Van Es, A.J.H., 1978. Feed evaluation for ruminants: I. The system in use from May 1977 onwards in the Netherlands. Livest. Prod. Sci. 5, 331–345]) and a safe RDPB level (± 200 g/day). On average 4.6 kg wheat DM was fed daily. Following trial 1, trial 2 was carried out, with the maize silage, grass silage and wheat fed in the same proportions as in trial 1, but fed ad libitum, to compare the intake level of the three diets. In both trials, the NaOH treated wheat resulted in the best performance with importantly increased milk yield and the highest yield of fat and protein corrected milk. Ensiled immature wheat resulted in a significant lower milk production and milk protein yield and in a higher milk fat content. In trial 1, DM-intake of the three groups was comparable due to the experimental design. In trial 2 intake of the cows fed NaOH treated wheat was significantly higher (23.5 vs. 21.1 kg/day for the other two groups).  相似文献   


9.
In swine and cattle given 0, 0.1, or 0.5 and 0, 0.5 mg of diacetoxyscirpenol (DAS)/kg of body weight, IV, respectively; DAS had a large volume of distribution and total body clearance. The shortness of the interval between halothane and DAS exposures significantly (P greater than 0.05) decreased DAS biotransformation. Urinary excretion of DAS as a parent compound was not an important route of elimination. In swine and cattle, DAS was transformed by sequential deacetylation to monoacetoxyscirpenol and scirpentriol.  相似文献   

10.
Groups of cattle, sheep and poultry were inoculated with a recombinant vaccinia virus expressing the haemagglutinin of the swine influenza virus A/NJ/11/76. No adverse clinical responses were recorded and none of the animals developed a viraemia when inoculated with the recombinant or wild-type vaccinia virus. Recombinant virus reisolated from lesions in cattle was stable, maintaining its thymidine kinase negative phenotype and ability to express the swine influenza haemagglutinin. Antibodies to the influenza haemagglutinin were detected in cattle, sheep and poultry inoculated with the recombinant virus. While no animals inoculated with wild-type virus developed these antibodies, there was no detectable spread of either recombinant or wild-type virus from the inoculation sites or to in-contact uninoculated animals. The results indicate that recombinant vaccinia viruses can induce immune responses in cattle, sheep and poultry demonstrating their potential as vaccine vectors in a variety of important veterinary species.  相似文献   

11.
To strengthen farm biosecurity, wildlife behaviors around livestock environments require significant attention. Livestock feed is considered one of essential factors that attract wildlife to the livestock environment. We experimentally studied wildlife response to cattle, swine, and chicken concentrated feeds in the forests surrounding poultry farms. In 14 feeding sites, four feed conditions were established: without feed (control); cattle feed; chicken feed; and swine feed. Wildlife behaviors at each feed point were monitored using infrared cameras. In 3,175 videos, 10 mammals were photographed on 10 or more occasions. Wildlife more frequently appeared at the points with feed than without feed. In addition, the number of videos that captured foraging or interest behaviors was largest for swine feed, followed by chicken feed, then cattle feed. There was a large difference among wildlife in their response to livestock feeds, although each species did not have a strong preference for a specific feed. Livestock feeds invite frequent visits by high and moderate response groups, especially omnivores and carnivores with omnivorous tendencies. Therefore, to protect against such wildlife intrusion, leftover feed and feed storage must be properly managed. This study also suggests that livestock feeds may not cause intrusions by rare response group species; hence, if their intrusions occur, they may be due to factors other than livestock feed. The study situation can partly reflect actual feed-stealing situations. The results will contribute to consider the properly management to protect livestock environments from wildlife intrusions.  相似文献   

12.
OBJECTIVE: To evaluate the features, underlying causes, results of diagnostic testing, and treatment of pneumothorax in dairy cattle. DESIGN: Retrospective study. ANIMALS: 30 dairy cattle. PROCEDURE: Medical records of all cattle with a diagnosis of pneumonia were reviewed. For cattle with pneumothorax, information was obtained pertaining to signalment, anamnesis, diagnosis, treatment, and outcome. Survival data were compared between cattle with pneumonia with or without pneumothorax. RESULTS: Pneumothorax was associated with bronchopneumonia in 18 cattle, interstitial pneumonia in 7 cattle, pharyngeal or laryngeal trauma in 3 cattle, and neonatal respiratory distress in 2 calves. Bovine respiratory syncytial virus was the most commonly detected infectious agent. Eighteen of 30 (60%) cattle survived; 8 were euthanatized and 4 died. Survival rate was 81% for cattle with pneumonia without pneumothorax during the same time period. Pneumothorax was a significant risk factor for failure to survive to discharge from the hospital for cattle with underlying chronic bronchopneumonia. CONCLUSIONS AND CLINICAL RELEVANCE: Pneumothorax in dairy cattle appears to occur most commonly in association with chronic bronchopneumonia. Cattle of both sexes and all ages can be affected.  相似文献   

13.
近年来,笔者对新疆伊犁地区奶牛养殖情况作了全面调查,发现奶牛疾病严重,繁殖率低,不孕症表现突出,给广大养殖户带来了很大的经济损失。为了解决奶牛在繁殖上的一些问题,推动养牛业的发展,对影响奶牛不孕症及治疗效果作了初步分析。  相似文献   

14.
OBJECTIVE: To establish the cost to the Queensland dairy industry of cattle tick infestation and its control, excluding the costs incurred from control measures directed specifically at tick fever and morbidity and mortality arising from tick fever. STUDY DESIGN: Economic models are described that have been based on empirical data relating to liveweight and milk yield loss, and on a survey of control practices and tick infestation. The first two models were designed to estimate costs of control and losses resulting from tick infestation on a single dairy farm. The third model developed estimates of the cost of tick infestation for each of four regions within the tick-infested area of Queensland. RESULTS: The overall cost to the Queensland dairy industry of the cattle tick (excluding the costs associated specifically with tick fever) and based on 1998 management practices, was $4,096,000 per annum. About 49% of this cost was related to the costs of control and 51% to losses in production. CONCLUSION: Cattle tick infestation represents a significant impost on dairy producers in Queensland, and although the actual cost will change as deregulation results in economic changes in the industry, infestations of ticks will continue to be expensive to control.  相似文献   

15.
16.
In response to uncertainty among cattle producers in Australia regarding the need to treat Bos indicus and B. indicus crossbreeds, the scientific literature relating to the productivity effects of Boophilus microplus on cattle of all breeds was reviewed. Estimates of the mean effect of each engorging tick (damage coefficient, d) were made from a simple analysis of the reported data. On average, each engorging female tick is responsible for the loss of 1.37 +/- 0.25 g bodyweight in B. taurus cattle. The comparable value for B. taurusxB. indicus cattle is 1.18 +/- 0.21 g/engorging tick. These values were not statistically significantly different, indicating that if a threshold approach to tick control were taken, then the threshold number of standard ticks would be the same regardless of cattle genotype. No studies provided useable estimates of the effect of tick infestation on pure B. indicus cattle. An economic threshold for treatment, below which acaricide application is not beneficial, can be predicted, using known values for the cost of acaricide application and the price of beef. However, the application of a threshold approach to control has not been embraced by government advisers and runs contrary to the accepted principals of strategic control programs.  相似文献   

17.
苜蓿干草和鲁梅克斯对奶牛生产性能的影响   总被引:7,自引:0,他引:7  
李胜利 《中国饲料》2002,(23):22-24
近年来 ,我国奶牛养殖业保持持续稳定的发展势头 ,奶类总产量从 1 984年的 2 5 9万t增加到2 0 0 0年的 91 9万t,并且在全国范围内形成了规模较大的乳业集团 (三元、光明、伊利、三鹿等 )。然而在我国奶牛生产中优质禾本科和豆科牧草的使用率还很低 ,大多数个体奶农还是以传统方式养奶牛 ,奶牛的常规饲料仍为劣质秸秆类粗饲料(玉米秸、麦秸和稻秸 )与三大料 (即玉米、麸皮、饼粕 )的简单混合 ,能量有余 ,蛋白质饲料单一 ,氨基酸搭配不当 ,矿物质、微量元素和维生素严重缺乏 ,饲料转化效率低 ,产奶量、乳脂率和乳蛋白率低 ,奶牛瘤胃酸中毒、…  相似文献   

18.
Single or chronic daily (30 d) doses of 14C-aniline (an aromatic amine) were administered to dairy cattle, swine and laying pullets to determine the amount of an ingested synfuel-related chemical that would remain in consumable animal products. The 14C-residues were found in muscle, liver, other edible organs and fat, as well as in milk and eggs. The predominant site of deposition in acute- and chronic-exposed pullets was kidney, followed by internal yolk (immature ovum of ovary) and then liver. Egg yolk was the major site of 14C-radioactivity in whole eggs. Liver, then kidney, were the major sites of deposition in acutely exposed swine; when chronically exposed, only liver showed preferential deposition with other tissues surveyed yielding similar concentration values. Dairy cattle yielded tissue distribution patterns similar to chronic swine. Within 8 h after an acute exposure, 14C-residue was detected in milk which reached its maximum at 24 to 32 h. Our data demonstrate that derived concentration values of 14C-residue in tissues was dependent upon the species studied as well as on the mode of exposure, acute versus chronic. Although the concentration values were variable, sufficient amounts of 14C-aniline and (or) its metabolites were found in consumable products.  相似文献   

19.
美国科学院全国研究理事会(NRC)制定的1989版乳牛营养需要量,在使用了10余年之后,已由经过修订的NRC2001版所替代。在NRC2001版中,首次单列章节专门阐述小母牛的生长和对小母牛生长的要求。对这个有关小母牛生长的新章节,有必要予以认真研读,并与NRC1989版加以比较。NRC2001版的技术先进性在于:它为使用者提供了一种基于Excel的小母牛营养需要量表生成程序和计算机化的乳牛程序。与NRC1989版中  相似文献   

20.
Phosphorus (P) is an essential nutrient and significant safety margins have until now been included in both feeding recommendations for cattle and allocation of P in practice. However, there is a need to optimize the utilization of P in cattle and thereby minimize its allocation and excretion. This demands well-defined requirements and availabilities of P in feeds as well as fairly precise use of this knowledge in practice. The purpose of this paper is to review the current knowledge and to give proposals for feeding phosphorus to cattle in relation to physiological requirement, availability of phosphorus in feeds, and minimal excretion of P. There is scientific and practical basis for a reduction of recommendations and allocation of P to cattle in the Nordic countries. No evidence or indication is found that surplus P relative to physiological requirement is beneficial. Future P feeding recommendations should continuously be based on the factorial method. The quantitatively most important improvement will be the increase and differentiation of the TAC value (true availability coefficient), which can be raised from 0.55 to 0.65 and 0.70 for the most common feeds. However, there is still no basis for a specific TAC for an individual feedstuff. When applying the recommended P allocation, it will be possible to increase the utilization of P in, e.g. high producing dairy cows, to 35–40%.  相似文献   

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