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91.
康宁木霉固态发酵改善茶渣营养价值   总被引:1,自引:0,他引:1  
本试验旨在研究康宁木霉固态发酵茶渣,提高茶渣营养价值,并筛选出最佳的发酵条件。用单因素试验优化发酵茶渣的基质比例(茶渣∶玉米粉=6∶4、7∶3、8∶2、9∶1)、料液比(3∶7、4∶6、5∶5、6∶4、7∶3)、接种量(2%、4%、6%、8%、10%)、发酵温度(25、28、31、34、37 ℃)和发酵时间(0、2、4、6、8、10、14、22 d)。以基质比例、发酵温度、接种量和发酵时间为影响因素,进行L9(34)正交试验确定茶渣最优发酵条件。测定各组发酵产物粗蛋白质、粗脂肪、还原糖、黄酮、皂苷和咖啡因含量,计算各组合的综合评分。确定最优条件后进行对比试验,比较了发酵前后茶渣的营养成分、活性物质和游离氨基酸含量。结果表明:1)单因素试验中,以下条件的综合评分最高:基质比例为7∶3,料液比为5∶5,接种量为8%,发酵温度为31 ℃,发酵时间为6 d。2)正交试验表明,康宁木霉发酵茶渣(料液比为5∶5)的最佳条件是:基质比例为7.0∶2.5,发酵温度为31 ℃,接种量为7%,发酵时间为6或7 d。3)与未发酵茶渣相比,最优条件下发酵茶渣的粗蛋白质、还原糖、黄酮、咖啡因、多种游离氨基酸含量和必需氨基酸/总氨基酸、风味氨基酸/总氨基酸均显著提高(P<0.05),皂苷含量显著降低(P<0.001),粗脂肪含量与未发酵茶渣无显著差异(P>0.05)。发酵6和7 d的茶渣营养成分和活性物质含量无显著差异(P>0.05)。由此可见,康宁木霉发酵茶渣能够改善茶渣的营养价值。  相似文献   
92.
Ectoparasites are the major causes of skin lesions in animals. Clinical, skin scraping examination, and histopathological studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. Mange mites, lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. Skin biopsies were collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. Of 1,000 sheep and 600 goats examined, 815 (81.50%) sheep and 327 (54.5%) goats were infested with one or more types of ectoparasites. Sarcoptes scabiei var ovis, Demodex ovis, Psoroptes ovis, Bovicola ovis, Melophagus ovinus, and Amblyomma variegatum and other tick species were identified from sheep. S. scabiei var caprae, Demodex caprae, Linognathus stenopsis, and A. variegatum and other tick species were identified from goats. Gross skin lesions or defects observed on the skin include stained and ragged wool, loss of wool/hair, nodules, crusts, lichenification, and fissuring. Microscopic evaluation of H and E stained skin sections revealed lesions in the epidermal layer such as hyperkeratosis, acanthosis, and melanin inconsistency on the basal cells of the epidermis. Follicular keratosis, perifolliculitis, frunculosis, perivasculitis, and aggregates of inflammatory cells (of acute and chronic type) with fibrosis were experiential in the dermal layer of the skin. Most of the skin lesions caused by ectoparasites are overlapping. Thus, ectoparasites control program should be executed to reduce skin lesions as skins are the major export commodity of the country.  相似文献   
93.
This study was performed to evaluate the infectivity of bradyzoites of two Besnoitia caprae isolates, BC-1 and BC-2, to inbred BALB/c mice. Each group of inbred BALB/c mice was inoculated intraperitoneally with 1 × 103, 1 × 104, 1 × 105, 5 × 105 and 1 × 106 of one of the two isolates of B. caprae bradyzoites. The mice were monitored daily for a period of 40 days for survival. After death of each mice, several passages from its peritoneal washing and tissues were analyzed using ribosomal DNA-specific PCR assay. Marked differences in pathogenicity between the isolates were seen. All the inbred BALB/c mice infected with BC-2 survived but all the mice that were administered with 1 × 05, 5 × 105 and 1 × 106 BC-1 bradyzoites were died within 4–9 days post-infection (DPI). Histopathological examination of the tissues of the dead mice revealed hyperemia and necrosis with presence of mononuclear and polymorphonuclear cell infiltration in myocardium, spleen and intestines together with interstitial pneumonia and peritonitis. All inbred BALB/c mice in the 1 × 103 and 1 × 104 groups of BC-1 inoculated mice survived and they were euthanized after 40 DPI. Chronic inflammation with infiltration of mononuclear cells was evident in myocardium, spleen, alveolar septa of the lungs of most of the examined tissues with hemorrhagic enteritis in the mice infected with 1x106 bradyzoites. The mice infected with different doses of BC-2 were euthanized after 40 DPI and no lesion was seen in histopathological sections of their organs. All peritoneal washings and examined tissues were PCR positive in BC-1 group. This experiment is the first report to show inbred BALB/c mice as a relevant model for B. caprae and demonstrates that this strain of inbred BALB/c mice is a suitable animal model for biological studies and examination of pathogenesis for this species of Besnoitia. The present findings also provide evidence for significant differences between the two isolates of B. caprae.  相似文献   
94.
Biological response modifiers (BRM) are compounds that interact with the immune system to regulate specific aspects of host response. The objective of this study was to describe clinical and morphological changes during involution of bovine mammary gland following a single-dose infusion of a BRM containing lipopolysaccharide and cellular fractions of Escherichia coli incorporated into liposomes. A massive leukocyte response and increased subepithelial stroma infiltration of mononuclear cells, eosinophils and mast cells was observed in BRM-treated quarters compared with untreated controls; however, morphologic parameters assessed at 11 days post infusion were indicative of only slightly accelerated involution compared with untreated controls. In addition, BRM infusion at the end of lactation did not interfere with mammary epithelial cell proliferation and caused only mild systemic effects.  相似文献   
95.
广东大峡谷自然保护区社区公众野生动物保护意识调查   总被引:4,自引:0,他引:4  
2008年6月,对广东大峡谷自然保护区社区公众野生动物保护意识进行了问卷调查。结果表明:(1)公众对野生动物保护知识匮乏,缺乏野生动物保护法制意识;(2)公众普遍对野生动物面临的威胁有较明确的认识,具有保护意愿,但缺乏保护野生动物的积极性和主动性;(3)公众接受野生动物保护教育的主要途径是电视。本文针对广东大峡谷自然保护区公众野生动物保护意识现状及其存在的问题,提出了一些建议。  相似文献   
96.
The presence, phenotype and function of Streptococcus uberis-specific T cells in the mammary gland secretion (MGS) and blood of cows exposed to S. uberis were assessed. MGS T cells in the udder were purified and incubated with autologous blood monocytes as antigen-presenting cells (APC). Most cows, irrespective of prior S. uberis infection status and lactation status, were shown to have S. uberis-specific T cells both in MGS and in the blood. When cells from a subgroup of cows were studied, it was found that the S. uberis-specific T cells produced high levels of interferon-gamma (IFN-γ), but low levels of interleukin-10 (IL-10). A high percentage of responding T cells were of the CD8 + memory (CD45RO) subset. T cells from the MGS specific for S. uberis were propagated from animals during the drying off period and expanded in vitro using interleukin-2 (IL-2) and S. uberis antigens. This led to the accumulation of T cells of the CD8 + subset bearing memory cell markers (CD45A , CD45RO + ), which released high levels of IFN-γ. Four of the five T cell lines derived from the MGS of three animals had substantial direct killing activity towards S. uberis in vitro. It is concluded that there is an emergence of S. uberis-specific bactericidal T cells in the MGS of cows after infection or environmental exposure to S. uberis. Vaccines aimed at activating and expanding this T cell population in the mammary glands of cattle may offer an avenue for the prevention of mastitis caused by S. uberis.  相似文献   
97.
Ornithobacterium rhinotracheale is a gram negative bacterial pathogen causing respiratory tract infections in poultry. Tracheal, lung and serum samples were obtained from 21 broiler flocks of 8 farms from a slaughterhouse located in south-eastern of Iran. Among 630 tracheal and lung samples from samples resulting from 315 chickens, 11 (3.5%) ORT isolates were identified using biochemical tests. The isolates originated from 9 (42.9%) flocks out of 4 farms. All of the isolates were recovered from tracheal swabs and showed an API 20NE identification biocode 0-2-2-0-0-0-4. Of the 420 serum samples examined by ELISA, 134 (31.9%) sera from 17 (81.0%) flocks were positive for ORT antibodies. These results indicate that ORT is present in most broiler flocks with respiratory disorders in southeast Iran.  相似文献   
98.
The present experiment was designed to study the pharmacokinetics of levofloxacin in six healthy cross bred female cow calves (4 to 6 months age) weighing between 40 to 80 kg. Plasma from blood was separated by centrifugation at 10,000 rpm. Quantitative estimation of levofloxacin was done by UV-VIS spectrophotometer at 286 nm. The mean maximum plasma concentration (Cpmax ) of levofloxacin in febrile calves (5.28?±?0.32 µg/ml) did not differ significantly as compared with healthy calves (4.50?±?0.22 µg/ml) after single dose (20 mg/kg) oral administration. The mean therapeutic plasma concentration ( Cpther ) of levofloxacin was maintained for longer period in febrile calves (10 h) as compared to healthy calves ( 8 h). The mean maximum urine concentration (Cumax) in febrile (40.86?±?2.19 µg/ml) also did not differ significantly as compared with healthy calves (39.38?±?2.43 µg/ml). No significant difference in various pharmacokinetic parameters of plasma was observed in healthy calves ( β?=?0.23?±?0.01/h ; t1/2 β?=?3.00?±?0.17 h and MRT?=?4.66?±?0.14 h ) and febrile calves ( β?=?0.23?±?0.01/ h; t1/2 β?=?3.05?±?0.16 h and MRT?=?5.04?±?0.14 h ) . The mean value of β, and t ½ β calculated in urine also did not differ between healthy and febrile calves. However, the value of MRT(3.79?±?0.07 h) and ClB(1.65?±?0.09 ml/kg/min) calculated in urine of febrile calves significantly(p?B?=?2.09?±?0.13 ml/kg/min). Based on kinetic profile levofloxacin may be given orally at the dose rate of 1.49 mg/kg B.W.at 8 h intervals in febrile calves.  相似文献   
99.
近年来,国内兴起建鳄鱼养殖场的热潮,而指导新养殖户们如何进行鳄鱼养殖场选址的相关研究尚未见报道。为此,笔者于2007年6月至2008年7月深入鳄鱼养殖场进行调查,探讨鳄鱼场选址时的主要考虑因素:温度、饲料、市场与交通、水质和安全等,并认为在实际操作过程中,其他的一些因素,如土地权属和水电供应等也不可忽略。  相似文献   
100.
Southeast Asian macaques are hosts of a number of Plasmodium infections, some of which are transmittable to humans. During examination of blood films of five wild-caught long-tailed macaques Macaca fascicularis from South China, malaria infection was detected in one of the monkeys. In order to isolate this parasite for identification and characterization, we experimentally passed this parasite through both Assamese (M. assamensis) and rhesus (M. mulatta) monkeys by intravenous injection of infected blood. This parasite morphologically resembled Plasmodium inui, and had a typical 72 h quartan periodicity. This parasite was infective to Anopheles dirus mosquitoes, and salivary gland sporozoites appeared 13 days post feeding. Feeding by 20 infected An. dirus mosquitoes on another Assamese monkey produced infection with a prepatent period of 8 days. Molecular analysis of the small subunit rRNA genes and the mitochondrial genome confirmed this parasite as an isolate of P. inui. In spleen-intact macaques, the infection had a protracted duration with parasites being detected during the rearing of the infected monkeys for over two years. In summary, this study identified a P. inui isolate and successfully passed this parasite through Assamese monkeys by both intravenous inoculation and mosquito transmission.  相似文献   
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