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71.
72.
Zhentian Li Defa Li Shiyan Qiao Xiaoping Zhu Canghai Huang 《Archives of Animal Nutrition》2003,57(4):267-277
This study was conducted to investigate the effects of a moderate dose of purified soybean agglutinin on performance and nitrogen digestibility in rats as well as to determine its effects on the protein, DNA and RNA content of the small intestine and pancreas. Twenty-four Sprague-Dawley rats were randomly allotted into one of four groups for a 10-day nitrogen balance experiment. The four groups of rats were fed 7 g of a casein-cornstarch based diet or a similar diet supplemented with 0.1, 0.2 or 0.4 mg/g purified soybean agglutinin. All experimental diets were adjusted to an identical nutrient level. Dose of soybean agglutinin had no significant effect on rat performance. Incorporation of soybean agglutinin in the diet reduced apparent protein digestibility and the utilization of dietary protein by increasing nitrogen loss from the faeces and urine. Fresh pancreatic weight increased in rats fed soybean agglutinin at a level of 0.4 mg/g in the diet compared to the control, but the dry pancreatic weight and the protein content of the pancreas did not differ among the four groups. However the DNA and RNA content of the pancreas had a tendency to increase with a higher level of soybean agglutinin. The weight of the jejunum and its protein, DNA and RNA content were not significantly affected by soybean agglutinin, but the dry weight and the RNA of the jejunum tended to increase with higher levels of soybean agglutinin in the diet. In conclusion, purified soybean agglutinin, at moderate levels in the rats diet, had negative effects on digestive function, such as nitrogen digestibility, nitrogen retention and nitrogen balance. As the level of soybean agglutinin increased, the effects became more pronounced. Meanwhile, hypertrophy of the pancreas was observed with higher doses of soybean agglutinin incorporation in the diets. 相似文献
73.
目的了解恩诺沙星对金黄色葡萄球菌(金葡菌)的抗菌活性及利血平对其抗菌活性的影响。方法采用对倍稀释浓度琼脂平板法测定抗菌药物的最低抑菌浓度(MIC)值,同法测定利血平对恩诺沙星对金葡菌MIC值的影响。结果利血平可有效增强恩诺沙星的抗菌活性,增大了恩诺沙星抑制金葡菌的抑菌圈直径,提高了恩诺沙星在组织中检测的灵敏度。研究发现利血平加入后中心浓度由0.5ul/ml变为0.0625ul/ml,最低检测限由0.125μg/ml降低到0.015625μg/ml。最低检测限减低了8倍。 相似文献
74.
将不同剂量的Epostanc静脉注射成年公兔,测定注射后1、2、3、24小时血清睾酮、皮质醇水平的变化。结果显示注射Epostanc后公兔血清睾酮水平增加且与剂量相关;低剂量Epostanc显著地降低血清皮质醇水平。 相似文献
75.
Identification of lactic acid bacteria in the feces of dairy cows fed whole crop maize silage to assess the survival of silage bacteria in the gut 下载免费PDF全文
Hongyan Han Chao Wang Yanbing Li Zhu Yu Qingfang Xu Guangpeng Li Tang Thuy Minh Naoki Nishino 《Animal Science Journal》2018,89(1):97-104
In order to assess the survival of lactic acid bacteria (LAB) in whole crop maize silage in the gut of dairy cows, one representative silage sample and three different feces samples were collected from dairy cows on three dairy farms in Hua Bei, China and three dairy farms in Kyushu, Japan. The composition of the bacterial community was examined by denaturing gradient gel electrophoresis and quantitative polymerase chain reaction. Lactobacillus acetotolerans was detected in all bunker‐made maize silage samples, regardless of the dairy farm or sampling region from which they were sourced. A total of eight LAB species were detected in the maize silage samples, of which three (L. acetotolerans, L. pontis and L. casei) appeared to survive digestion. The populations of L. acetotolerans in silage and feces were 106–7 and 103–4 copies/g, respectively, indicating that, even for the LAB species showing potential survival in the gut, competition in this niche may be harsh and the population may substantially decrease during the digestion process. It may be difficult for silage LAB to survive in the gut of silage‐fed dairy cows, because marked decrease in population can take place during the digestion process, even for surviving species. 相似文献
76.
Cooper RG 《Tropical animal health and production》2007,39(6):439-442
Data from post-mortem and field studies were obtained that discussed poisoning in ostriches following ingestion of toxic plants.
From the notes, all plants studied caused death in ostriches and there was systemic organ damage. Poisoning from Sarcostemma viminale (Melktou) resulted in beak patting, muscular tremors and head flopping, followed by collapse and violent kicking before death.
Ingestion of Combretum oatesii (Red wings) seeds from plants in free grazing pastures resulted in vomiting, restlessness, eyelid flicking, collapse and
kicking movements. Dichapetalum cymosum (Gifblaar) killed an ostrich after episodes of shaking legs, rapid respiration and bradycardia and hyperaemia of the lungs,
liver and kidneys. Poisoning from Senecio sceleratus (Ragwort) caused skin haemorrhages and bleeding in tracheal mucous membranes, the pericardium, diaphragm and interperitoneal
membrane. Consumption of drupes from Melia azedarach (Syringa berry) caused muscle tremors, kicking movements and respiratory distress. Lantana camara (Cherry pie) poisoning resulted in extremely inflamed eyes with copious yellow exudates extending down their beaks and onto
their necks. Bentonite was administered by gavage at a dose of 5 g/kg. Poisoning in these cases is usually associated with
the farmer allowing his/her birds to roam free-range in paddocks in which toxic plants are growing. Toxic plants should be
removed from grass cut for hay.
The author is willing to send photographs of all poisonous plants if requested by a reader. 相似文献
77.
Rosine Manishimwe Kizito Nishimwe Lonzy Ojok 《Tropical animal health and production》2017,49(6):1101-1106
The irrational use of antibiotics in humans and animals is highly related to the emergence and increase of antibiotic-resistant bacteria worldwide. A cross-sectional survey aimed at evaluating the current level of practices regarding antibiotic use in farm animals in Rwanda was carried out countrywide. Interviews were conducted on 229 farmers rearing different types of animals. The study has revealed that almost all respondent farmers could name at least one antibiotic used in farm animals and peni-streptomycin was named by most of them (95.6%). The use of antibiotics in farm animals was observed in the majority of respondents (97.4%). It was found that 44.4 and 26.5% of respondents reported that they used antibiotics for disease prevention and growth promotion, respectively. The use of non-prescribed antibiotics in animals was also reported by more than the half of respondent farmers (55.6%). The majority of farmers had a moderate level of practices regarding antibiotic use in farm animals (73.5%), very few had a high level (26%) and only one respondent had a low level. The high level of practices in regard to antibiotic use in animals was associated with the location of the farm, the type of reared animals, and the rearing system. The results of this study give an insight into antibiotics usage practices in farm animals in Rwanda. The generated information can guide sensitizations and promotions of the prudent use of antibiotics among farmers in order to limit the increase of antibiotic resistance in the country. 相似文献
78.
河西走廊的草地资源位于西北荒漠的大背景中,由山地、荒漠和绿洲三个子系统构成,其中荒漠子系统居主导地位,具有先天的脆弱性。它们在人为干预下,在自然生态系统的农业化过程中,发生了山地一绿洲一荒漠组成的耦合农业系统。由于耦合不够完善,它所固有的相悖因素未能有效控制,形成涵有系列相悖因子群的系统相悖。主要表现为时间相悖,空间相悖和种间相悖。三者互相影响,但时间相悖起主导作用,使系统的生态危机加剧。它通常表现为草原退化。对草地农业生态系统的自由能的调控,保持自由能的积累和输出基本相当,是防止草原退化的根本出路。草原退化是草地对于草食动物压迫的对策系统和动物对于草地负荷行为的对策系统的综合反映。放牧程度可以作为草原退化过程的向量系统,但不是草原退化的本质。 相似文献
79.
80.
Wang R Yuan LG He LM Zhu LX Luo XY Zhang CY Yu JJ Fang BH Liu YH 《Journal of veterinary pharmacology and therapeutics》2011,34(3):247-251
Wang, R., Yuan, L.G., He, L.M., Zhu, L.X., Luo, X.Y., Zhang, C.Y., Yu, J.J., Fang, B.H., Liu, Y.H. Pharmacokinetics and bioavailability of valnemulin in broiler chickens. J. vet. Pharmacol. Therap. 34 , 247–251. The objective of this study was to investigate the pharmacokinetics and bioavailability of valnemulin in broiler chickens after intravenous (i.v.), intramuscular (i.m.) and oral administrations of 10 mg/kg body weight (bw). Plasma samples were analyzed by high‐performance liquid chromatography–tandem mass spectrometry (HPLC‐MS/MS). Pharmacokinetic characterization was performed by non‐compartmental analysis using WinNonlin program. After intravenous administration, distribution was wide with the volume of distribution based on terminal phase(Vz) of 4.27 ± 0.99 L /kg. Mean valnemulin t1/2β(h), Clβ(L /h /kg), Vss (L /kg) and AUC(0–∞)(μg·h /mL) values were 2.85, 0.99, 2.72 and 10.34, respectively. After intramuscular administration, valnemulin was rapidly absorbed with a Cmax of 2.2 μg/mL achieved at 0.43 h (tmax), and the absolute bioavailability (F) was 88.81%; and for the oral route the same parameters were 0.66 ± 0.15 μg/mL, 1.54 ± 0.27 h and 74.42%. A multiple‐peak phenomenon was present after oral administration. The plasma profile of valnemulin exhibited a secondary peak during 2–6 h and a tertiary peak at 32 h. The favorable PK behavior, such as the wide distribution, slow elimination and acceptable bioavailability indicated that it is likely to be effective in chickens. 相似文献