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91.
G.‐F. LI L‐B. LIU Y‐L. TAN L‐Z. LIU H‐Z. DENG H. WAN W‐Z. ZHONG S‐J. CHEN 《Aquaculture Nutrition》2011,17(2):e263-e270
The present study was to determine in vitro effect of levamisole on the immune functions of Barbel chub (Squaliobarbus curriculus), head–kidney‐derived (HKM), spleen‐derived (SM) and peripheral blood monocyte‐derived macrophage (PBM). Macrophages were incubated with levamisole 103, 101, 10−1 and 10−3 ng mL−1 to assay the cell viability, respiratory burst and phagocytosis. The results showed that macrophages treated with levamisole 10−3 ng mL−1 gave a maximum respiratory burst response, whereas levamisole 103 ng mL−1 had no effect. Phagocytosis activity of the macrophages treated with levamisole enhanced significantly when compared to control, maximum response being at 10−3 ng mL−1. While using the methylthiazoletetrazolium method to measure the cell activity for 12, 24, 36, 48, 60 h, there was no significant role on proliferation and the cell viability began to decline after 24 h. In conclusion, levamisole is a potent enhancer of Barbel chub macrophage activity with low concentration. 相似文献
92.
Hayasaka Y Adams KS Pocock KF Baldock GA Waters EJ Høj PB 《Journal of agricultural and food chemistry》2001,49(4):1830-1839
Methods based on liquid chromatography-mass spectrometry (LC-MS) and protein trap mass spectrometry (trap-MS) were developed to determine the complement of pathogenesis-related (PR) proteins in grape juice. Trap-MS was superior to LC-MS in terms of simplicity, rapidity, and sensitivity. Proteins with a wide range of masses (13--33 kDa) were found in the juices of 19 different varieties of grape (Vitis vinifera) and were identified as mostly PR-5 type (thaumatin-like) and PR-3 type (chitinases) proteins. Although the PR proteins in juices of grapes are highly conserved, small consistent differences in molecular masses were noted when otherwise identical proteins were compared from different varieties. These differences persisted through different harvest years and in fruits grown in different Australian locations. With the definition of four different masses for PR-5 proteins (range = 21,239--21,272 Da) and nine different masses of PR-3 proteins (range = 25,330--25,631 Da) and using statistical analysis, the methods developed could be used for varietal differentiation of grapes grown in several South Australian locations on the basis of the PR protein composition of the juice. It remains to be seen whether this technology can be extended to grapes grown worldwide and to wine and other fruit-derived products to assist with label integrity to the benefit of consumers. 相似文献
93.
Aortic rupture causing cardiac tamponade in a 24‐day‐old Friesian colt with concurrent colonic Chlamydiosis and Balantidiasis 下载免费PDF全文
M. Diel de Amorim K. Nielsen B. McKell Y. Huang C. Card 《Equine Veterinary Education》2016,28(2):68-73
A 24‐day‐old Friesian colt died suddenly and a physical examination the morning the foal died showed no abnormalities and serum IgG levels >8.0 g/l. Necropsy examination revealed haemopericardium and a 2 cm transverse tear at the root of the aorta. The foal was also found to have Chlamydophila spp. in the epithelium and Balantidium coli on the mucosal surface of the large colon. An aortic rupture is a novel finding in a foal, colonic Chlamydiosis has not been previously reported in horses and Balantidium coli has not been reported in equids in North America. 相似文献
94.
Effects of Moringa oleifera silage on milk yield,nutrient digestibility and serum biochemical indexes of lactating dairy cows 下载免费PDF全文
B. Zeng J. J. Sun T. Chen B. L. Sun Q. He X. Y. Chen Y. L. Zhang Q. Y. Xi 《Journal of animal physiology and animal nutrition》2018,102(1):75-81
This study investigated the effects of Moringa oleifera (MO) as a partial substitute of alfalfa hay on milk yield, nutrient apparent digestibility and serum biochemical indexes of dairy cows. MO was harvested at 120 days post‐seeding. Fresh MO was cut, mixed with chopped oat hay (425:575 on a DM basis), ensiled and stored for 60 days. Sixty healthy Holstein dairy cows were allocated to one of three groups: NM (no MO or control), LM (low MO; 25% alfalfa hay and 50% maize silage were replaced by MO silage) or HM (high MO; 50% alfalfa hay and 100% maize silage were replaced by MO silage). The feeding trial lasted 35 days. The LM and HM diets did not affect dry matter (DM) intake, milk yield or milk composition (lactose, milk fat, milk protein and somatic cell count). The apparent digestibility of DM and NDF was lower for HM group than NM group. Additionally, there were no significant differences in serum biochemical indexes between the LM and NM groups. The HM group had lower serum concentrations of total cholesterol, high‐density lipoprotein cholesterol, and low‐density lipoprotein cholesterol and higher serum concentrations of urea than the NM group. The partial replacement of alfalfa hay (≤50%) and maize silage with MO silage had no negative effects on milk yield, in vivo nutrient apparent digestibility or serum biochemical indexes of lactating cows. 相似文献
95.
D. Moret-Fernández Y. PueyoC.G. Bueno C.L. Alados 《Agricultural Water Management》2011,98(12):1822-1827
Pasture productivity depends on soil hydro-physical properties, which in turn are deeply affected by livestock grazing. However, the comparative response of different soil types, and particularly gypseous soil types, to grazing has hardly been studied before. This paper compares the effect of grazing on the soil hydro-physical properties of silty gypseous (Gy) and non-gypseous (NGy) soils located in a semi-arid region (Middle Ebro Valley, NE, Spain). Two different soil managements were selected: ungrazed natural shrubland (N) and grazed shrubland (GR) soils. The gypsum, CaCO3 and organic matter content (OM), soil texture, soil bulk density (ρb), penetration resistance (PR), saturated sorptivity (S), hydraulic conductivity (K), and the water retention curve (WRC) for undisturbed soil samples from 1 to 10 cm depth soil layer were measured. The ρb and PR in NGy soils were significantly higher than those observed in the Gy ones. Soil compaction due to grazing treatment tended to increase ρb and decrease the K and S values. While no differences in PR were observed in the Gy soils between grazing treatments, the PR measured in the NGy soils under GR was significantly higher than the corresponding values observed under N. Differences in K and S between GR and N treatments were only significant (p < 0.05) in NGy soils, where K and S values under the N treatment were almost four times greater than the corresponding values measured under GR. Overall, no differences in the WRCs were observed between soil types and grazing treatments. While the WRCs of NGy soils were not significantly affected by the grazing treatment, Gy soils under N treatment present a significantly higher level of soil macropores than under GR treatment. The hydro-physical features of Gy soils tended to be less affected by grazing than those of the NGy soils. These results suggest that livestock grazing, in both Gy and NGy soils, has a negative effect on the physical soil properties, which should be taken into account by land managers of these semi-arid regions where silty gypseous and non-gypseous areas coexist. 相似文献
96.
Response of labile organic C and N pools to plastic film removal from semiarid farmland soil 下载免费PDF全文
S. S. Luo L. Zhu J. L. Liu L. D. Bu S. C. Yue Y. F. Shen S. Q. Li 《Soil Use and Management》2016,32(4):535-542
To examine the effects of plastic film removal on grain yield and soil organic matter (SOM), a spring maize (Zea may L.) field experiment was conducted for 5 yr at Changwu Agricultural and Ecological Experimental Station of Northwest China. Compared with traditional plastic film mulching during entire growing stages (FM), plastic film removal at the silking stage (RM) resulted in a 6.3% higher average maize yield. Under the RM treatment, soil organic carbon and total nitrogen significantly increased after the 5‐yr cultivation in the 0‐ to 20‐cm layer. Significant increases in extractable organic C (EOC), KMnO4‐oxidizable C (KMnO4‐C) and C management index (CMI) in the 0‐ to 20‐cm layer, and light fraction organic C and EOC in the 20‐ to 40‐cm layer were observed in response to plastic film removal after the 1‐yr treatment; the responses were more significant after 5 yr. Under the RM treatment, significant increases in microbial biomass C, light fraction organic N, extractable organic N, KMnO4‐C and CMI were also observed after five years in the 20‐ to 40‐cm layer. Moreover, KMnO4‐C and EOC were much more sensitive than other labile SOM fractions to the application of RM, even after only 1 yr of cultivation. Therefore, compared with mulching for the whole growing season, plastic film removal at the maize silking stage is an effective option for increasing yields and enhancing SOM concentration and soil sustainability in the regions with semiarid monsoon climates that have sufficient rainfall during maize reproductive stages. 相似文献
97.
Dietary supplementation with Acanthopanax senticosus extract enhances gut health in weanling piglets
Jun Fang F.Y. Yan X.F. Kong Z. Ruan Z.Q. Liu R.L. Huang T.J. Li M.M. Geng F. Yang Y.Z. Zhang Peng Li Joshua Gong G.Y. Wu M.Z. Fan Y.L. Liu Y.Q Hou Y.L. Yin 《Livestock Science》2009,123(2-3):268-275
The present study was conducted to investigate the effects of Acanthopanax senticosus extract (ASE) as a dietary additive on gut health in weanling piglets by examining diarrhea frequency, intestinal microbiota and morphology. A total of 96 Duroc× (Landrace × Yorkshire) piglets weaned at 21 days of age with an average initial body weight (BW) of 5.6 ± 0.4 kg were randomly assigned to 3 treatment groups with 4 duplicates of 8 piglets each. The piglets were fed basal diet to which had been added 0 or 1 g/kg of ASE, or 0.7 g/kg antibiotics, respectively. Fecal consistence was monitored twice daily and the frequency of diarrhea was calculated. On day 21 after the initiation of supplementation, 8 piglets were randomly selected from each treatment group (2 piglets per pen) and slaughtered. The jejunum, ileum, colon and cecum were then excised and fixed in 10% neutral formalin solution to determine villus height and crypt depth, after their contents were collected to determine microbiota. The results showed that dietary supplementation with ASE increased (P < 0.05) the density of bacterial populations that co-migrated with Lactobacillus amylovorus, Lactobacillus salivarius, Bacillus subtilis, and Clostridium lituseburens, but decreased (P < 0.05) those co-migrating with Staphylococcus aureus, Salmonella typhimurium, Ruminococcus forques, and E. coli O157:H7 in the PCR-DGGE profiling analysis when compared with the control group. The villus height of the duodenum, jejunum and ileum increased (P < 0.05) by 14.8, 13.7 and 10.0%, while the crypt depth decreased (P < 0.05) by 17.9, 9.1 and 12.1%, respectively, in response to dietary ASE supplementation. Additionally dietary supplementation with ASE or an antibiotic decreased (P < 0.05) the frequency of diarrhea by 55.6 and 52.2%, respectively, compared with the control group. In conclusion, these findings suggest that dietary supplementation with ASE could regulate the microbiota composition and maintain a normal morphology of gut mucosa in weanling piglets, thereby decreasing diarrhea that resulted from weaning stress. 相似文献
98.
Water shortage has become a major agricultural concern, and “The Sustainable Water Resources Research Program” in Korea is currently addressing this problem through the development of treatment systems for reclaiming wastewater and the assessment of human health risks associated with its reuse. Through this program, started in 2001, many studies have examined various water resources. Reclaiming wastewater is one way to alleviate water-shortage pressures, and one of the major potential uses of reclaimed water is irrigation. However, the main concern with reusing reclaimed wastewater is the increased likelihood of human contact that might result in exposure to pathogens and increased health risks. Relatively few studies have examined the toxic risks using reclaimed wastewater for irrigation in rice paddy fields. This study provides an overview of methods for quantitative microbial risk assessment and toxic risk assessment of heavy metal concentrations developed in the previous studies that can be applied to the evaluation of rice paddy fields irrigated with reclaimed wastewater in South Korea. 相似文献
99.
Douglas fir (Pseudotsuga menziessi [Mirb.] Franco) seedlings from a half diallel mating design showed significant family by nutrient interactions when grown
in a 3N × 3P × 15 family factorial experiment for 2 yr. Differences in response of these families to N and P treatment levels
were related to nutrient productivity (dry matter production nutrient−1 time−1), but unrelated to the proportion of dry matter allocated to root growth, or to nutrient net uptake rate. Significance of
general combining ability for N and K productivity showed clonal control of these characters. Evidence for genetic control
of tissue N% and K%, shoot:root ratio and N uptake rate were also shown. 相似文献
100.
Effect of ensiling whole crop oat with lucerne in different ratios on fermentation quality,aerobic stability and in vitro digestibility on the Tibetan plateau 下载免费PDF全文
L. Chen G. Guo X. J. Yuan J. Zhang A. Y. Wen X. H. Sun T. Shao 《Journal of animal physiology and animal nutrition》2017,101(5):e144-e153
The objective of this study was to determine the effect of ensiling different ratios of whole crop oat to lucerne on fermentation quality, aerobic stability and in vitro digestibility of silage on the Tibetan plateau. Four experimental treatments were produced varying in the ratio of forages on a fresh matter (FM) basis: 1) 100% oat (control, dry matter (DM) content: 317 g/kg), 2) 90% oat + 10% lucerne (OL10, DM content: 316 g/kg), 3) 80% oat+ 20% lucerne (OL20, DM content: 317 g/kg) and 4) 70% oat+ 30% lucerne (OL30, DM content: 318 g/kg). All treatments were packed into laboratory‐scale silos and ensiled for 60 days and then subjected to an aerobic stability test for 15 days. Further, the four experimental treatments were incubated in vitro with buffered rumen fluid to study the nutrient digestibility. All silages were well preserved with low pH and NH3‐N contents, and high lactic acid contents and V‐scores (evaluation of silage quality). Increasing the lucerne proportion increased (p < 0.05) crude protein (CP) content of silage, whereas neutral (NDF) and acid (ADF) detergent fibre contents were not affected. Under aerobic conditions, the control silage showed higher (p < 0.05) yeast counts (>105 cfu/g FM) followed by OL10 silage, and OL10 silage improved aerobic stability for 74 h. OL20 and OL30 silages showed fewer (p < 0.05) yeasts (<105 cfu/g FM) and markedly (p < 0.05) improved the aerobic stability (>360 h). After 48‐h incubation, OL30 silage increased (p < 0.05) in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) compared with the control silage. These results suggest that replacing oat with lucerne had no unfavourable effects on fermentation quality of silage, but improved CP content, aerobic stability IVDMD and IVNDFD. OL30 silage was the best among the three mixed silages. 相似文献