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41.
鸡粪和奶牛粪对小麦和油菜光合特性的影响 总被引：1，自引：0，他引：1
通过盆栽试验研究鸡粪和奶牛粪对小麦和油菜光合速率及蒸腾速率的影响。结果表明：鸡粪和奶牛粪对小麦叶片的光合速率的影响，因小麦生育时期的不同而异。苗期和孕穗期单叶光合速率提高；而其余生长期，施肥效果不明显。鸡粪处理（７５ｔ／ｈｍ２）可提高小麦水分利用系数９．８％～８１．３％；而奶牛粪肥，在孕穗前增加小麦水分利用效率９．４％～５０％，而后则有降低水分效率之趋势。两种粪肥均可提高油菜的单叶光合速率，各种肥料的效果因生育期和施肥量的不同而有差异。越冬前各施肥处理均增加了油菜的蒸腾速率，降低水分效率１．５％～２２．２％；越冬后，奶牛粪肥处理提高了蒸腾速率，而鸡粪则降低了油菜的蒸腾作用，各施肥处理均可提高油菜的水分效率，鸡粪为４．３％～２７１％，奶牛粪为１．９％～８３．９％． 相似文献
42.
Assessment of the production and dispersal of faecal waste from the sea‐cage aquaculture of spiny lobsters 
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下载免费PDF全文 Despite the rapid expansion of spiny lobster aquaculture, very little is known about its potential environmental impacts. In an effort to understand the potential impacts of sea‐cage culture of spiny lobsters, the faecal output and settling velocity of faeces of spiny lobster were quantified. These data were then used in hydrodynamic modelling to assess the dispersal pattern of faecal material from two sizes of hypothetical spiny lobster farms, so that inferences about likely benthic impacts could be made by modelling different scenarios of farm stocking density and food conversion efficiency. The overall mean settling velocity of lobster faecal strands was 0.9 ± 0.05 cm s?1. There was a positive correlation between both the weight and density of faecal strands and their settling velocity. Conversely, neither the length nor the surface area of faecal strands was correlated with the settling velocity. Hydrodynamic modelling showed that faecal material deposition mainly occurred directly beneath the sea‐cages. The density of faecal material deposition increased proportionately with higher stocking density and FCR values. Overall, the results indicate that the deposition of faecal waste from sea‐cage lobster aquaculture is unlikely to cause widespread benthic impacts when operating to the current highest commercial stocking and feeding levels. 相似文献
43.
【目的】探讨亚临床低血钙症奶牛饲料采食量、泌乳量、粪尿排放量及粪污所产生污染气体排放特征的关系。【方法】黑龙江某集约化奶牛养殖场选取产后7—14 d年龄、体况、胎次相近的奶牛12头,根据血钙指标分为亚临床低血钙症组和健康组奶牛各6头,每头奶牛分别单独饲养,连续饲养4 d。每天采血检测血液中Ca、BHBA、NEFA、CLU、P、Mg指标含量;记录每头牛每天泌乳量、采食量、粪、尿排放量;通过简易动态箱法对试验奶牛粪尿进行混合,检测混合物产生的NH_3、CO_2、CH_4气体排放量并进行分析。【结果】亚临床低血钙症组奶牛血清Ca、P、Mg浓度极显著低于健康组奶牛(P0.01),CLU显著低于健康组(P0.05),BHBA浓度显著高于健康组(P0.05),NEFA浓度极显著高于健康组奶牛(P0.01);亚临床低血钙症组奶牛产奶量和4%能量校正乳(ECM)极显著高于健康组(P0.01),排粪量显著高于健康组(P0.05);干物质消化率和尿量的差异虽然不显著但都有升高趋势。亚临床低血钙组奶牛采食1 kg干物质的产奶量极显著升高(P0.01),采食1 kg干物质的排粪量显著升高(P0.05);健康组和亚临床低血钙症组奶牛CH4的排放曲线无明显差异,两组的产气趋势基本相同,于试验的52 h左右出现峰值,之后下降;总体上看CO_2的排放没有明显变化趋势,无明显规律,健康组和亚临床低血钙症组分别在48和36 h处出现排放高峰,亚临床低血钙症组出现峰值的时间要早于健康组,之后下降随即无规律起伏。亚临床低血钙症组的CO_2累计排放量随时间的推移低于健康组;健康组奶牛NH_3排放浓度在24h处出现高峰,随后降低,45 h再次出现峰值,之后排放浓度逐渐降低。亚临床低血钙症组奶牛NH_3排放浓度在21 h处出现峰值,之后排放浓度降低,两组试验的折线趋势基本一致,都是出现峰值后浓度降低但都是有起伏的波动。亚临床低血钙症组NH_3的累计排放量低于健康组。【结论】亚临床低血钙症奶牛患病期间由于采食摄取营养物质不能满足泌乳需求而处于能量及钙负平衡状态。同时肠道消化吸收率增加,用于满足泌乳对能量的需求;在相同质量的粪尿混合物检测情况下亚临床低血钙症不会影响CH_4的排放量,但亚临床低血钙奶牛粪尿中NH3和CO_2排放量低于健康牛,然而降低的温室气体排放是否与肠道消化吸收率的增加促进了饲料能量的吸收有关利用仍需进一步研究。 相似文献
44.
The protein, carbohydrate and lipid contents of the food ingested and their absorption in the intestine ofHepsetus odoe in Ado-Ekiti Reservoir, Ekiti State, Nigeria were investigated. Samples were analysed chemically for protein, fat and carbohydrate using the official methods of analysis described by the Association of Official Analytical Chemist. The ingested food had mean total protein, mean total carbohydrate and mean total lipid of 60.2% - 8.55%, 15.4% ± 1.9% and 15.6% ±1.1% of the organic content respectively. Calculated mean total percentages absorbed were 72.4% protein, 52% carbohydrate and 51.5% lipid. The foregut had the highest percentage absorption while the hindgut had the lowest for all the nutrients. Different sizes of fish showed different dietary protein, carbohydrate and lipid contents. Absorptive capacity for these components of the food also varied with fish size. 相似文献
45.
46.
The short-term influence of dung deposition and the further redistribution of dung by dung beetles were studied under a resting place of the red howler monkey (Alouatta seniculus) living in tropical rainforests of South America. Monkey dung was experimentally clumped on the field in a place used by troops of howler monkeys for resting in the Nouragues Reserve Station, French Guiana. Dung-treated plots were sampled serially over three weeks and compared with controls located in their immediate vicinity. The composition of the soil matrix (top 10 cm) was studied in successive microlayers using an optical method. Under the influence of dung beetle activity, the topsoil became more homogeneous by losing its litter, its content in earthworm faeces increased in the course of time, and surface mineral deposits were penetrated by roots. The results were interpreted in the light of present knowledge on the effects of soil animal activity on plant growth and survival of seedlings. 相似文献
47.
M Sneyers C Thiriart C Buryns A.-F Lambert C Collignon A Schwers P Coppe H Antoine J.D Franssen J Urbain L Karelle-Bui P.-P Pastoret 《Comparative immunology, microbiology and infectious diseases》1989,12(4):95-104
Monoclonal antibodies have been produced against the 81/36F strain of rotavirus. One of them, was chosen as diagnostic reagent: it showed high ELISA reactivity with all the bovine, human and porcine rotavirus strains tested and reacted with VP6, structural protein product known to support the common rotavirus antigen.
A sandwich ELISA procedure using the chosen monoclonal as “capture and detecting” antibody was performed to detect rotavirus in faecal samples from experimentally inoculated newborn calves: it always gave a negative response with meconium and a positive response for the stool specimens which rotavirus have been isolated. This assay was compared with Enzygnost and Slidex Rota Kit tests and with a non-commercial sandwich ELISA test using polyclonal antibodies: it showed more sensitivity than the agglutination test and was as sensitive as the other two tests to detect rotavirus in routine diagnostic material. The test evaluated showed no equivocal results. 相似文献
48.
Objective: To assess the toxicity of residues of ivermectin and moxidectin in cattle faeces collected at intervals after treatment.
Design: Replicated bioassays of faeces using larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica .
Animals: Two groups of five Murray Grey x Aberdeen Angus steers were treated with injectable formulations of ivermectin and moxidectin respectively. A third group was used as an untreated control.
Procedure: Newly emerged fly larvae were reared in the dung of treated animals.
Results: Drug residues in faeces collected 3 to 35 days after treatment with an injectable formulation of moxidectin had no significant effect on the survival of larvae of M vetustissima . Similarly, faeces dropped up to seven days after treatment caused no significant reduction in larval survival in M domestica . In day 2 dung, residues of moxidectin delayed development of M vetustissima larvae, but had no effect on their survival. In contrast, ivermectin-treated steers, produced dung that inhibited larval development of both M vetustissima and M domestica for 7 to 14 days after treatment. Significant reductions in survival of M vetustissima larvae occurred in dung collected on days 21 and 28 after treatment, but by day 35 survival did not differ from that in control dung.
Conclusion: Excreted faecal residues of moxidectin are relatively innocuous to larvae of both M vetustissima and M domestica . Those of ivermectin inhibit survival for 7 to 14 days after treatment and are likely to have adverse effects on non-target organisms. 相似文献
Design: Replicated bioassays of faeces using larvae of the bush fly, Musca vetustissima and the house fly, Musca domestica .
Animals: Two groups of five Murray Grey x Aberdeen Angus steers were treated with injectable formulations of ivermectin and moxidectin respectively. A third group was used as an untreated control.
Procedure: Newly emerged fly larvae were reared in the dung of treated animals.
Results: Drug residues in faeces collected 3 to 35 days after treatment with an injectable formulation of moxidectin had no significant effect on the survival of larvae of M vetustissima . Similarly, faeces dropped up to seven days after treatment caused no significant reduction in larval survival in M domestica . In day 2 dung, residues of moxidectin delayed development of M vetustissima larvae, but had no effect on their survival. In contrast, ivermectin-treated steers, produced dung that inhibited larval development of both M vetustissima and M domestica for 7 to 14 days after treatment. Significant reductions in survival of M vetustissima larvae occurred in dung collected on days 21 and 28 after treatment, but by day 35 survival did not differ from that in control dung.
Conclusion: Excreted faecal residues of moxidectin are relatively innocuous to larvae of both M vetustissima and M domestica . Those of ivermectin inhibit survival for 7 to 14 days after treatment and are likely to have adverse effects on non-target organisms. 相似文献
49.
Objectives To compare the survival of larvae of a dung-breeding fly in the faeces of cattle treated either with an injectable formulation of abamectin, or with oral or injectable formulations of ivermectin.
Design Replicated bioassays were conducted on larvae of the bush fly, Musca vetustissima, using faeces collected before and at intervals after drug treatment.
Animals Two cows and their calves were allocated to each of three drug treatments and dosed according to individual weights.
Procedures Differences in the proportions of larvae pupariating were used as measures of the toxicity of drug residues.
Results Development of fly larvae was inhibited in all faeces collected 1 to 4 days after treatment. In cattle treated with oral ivermectin, there was reduced larval survival in faeces collected 8 and 16 days after treatment, but by day 32, survival was equivalent to that recorded in the faeces of untreated cattle. With injectable ivermectin, there was no survival at day 8, limited survival at day 16 and, at day 32, survival was not significantly affected. With injectable abamectin, survival was completely suppressed until day 32, at which time the number of pupariating larvae did not differ significantly from that recorded in faeces from untreated animals.
Conclusion The oral formulation of ivermectin is eliminated more rapidly than the injectable formulation and, as a consequence, is likely to be less harmful to dung-feeding insects. Abamectin and ivermectin appear to equally toxic larvae of M vetustissima. 相似文献
Design Replicated bioassays were conducted on larvae of the bush fly, Musca vetustissima, using faeces collected before and at intervals after drug treatment.
Animals Two cows and their calves were allocated to each of three drug treatments and dosed according to individual weights.
Procedures Differences in the proportions of larvae pupariating were used as measures of the toxicity of drug residues.
Results Development of fly larvae was inhibited in all faeces collected 1 to 4 days after treatment. In cattle treated with oral ivermectin, there was reduced larval survival in faeces collected 8 and 16 days after treatment, but by day 32, survival was equivalent to that recorded in the faeces of untreated cattle. With injectable ivermectin, there was no survival at day 8, limited survival at day 16 and, at day 32, survival was not significantly affected. With injectable abamectin, survival was completely suppressed until day 32, at which time the number of pupariating larvae did not differ significantly from that recorded in faeces from untreated animals.
Conclusion The oral formulation of ivermectin is eliminated more rapidly than the injectable formulation and, as a consequence, is likely to be less harmful to dung-feeding insects. Abamectin and ivermectin appear to equally toxic larvae of M vetustissima. 相似文献
50.
Vladimir Urubschurov Christina Stroebel Elena Günther Kristin Romanowski Kirsten Büsing Annette Zeyner 《Journal of animal physiology and animal nutrition》2019,103(3):915-924
Effects of probiotics on the intestinal microbiota of foals are yet insufficiently studied. The aim of this study was to investigate whether supplementation of Lactobacillus rhamnosus (DSM 7133) and Enterococcus faecium (DSM 7134) influences the bacterial composition of the faecal microbiota of foals. A total of 34 newborn foals were randomly assigned to the placebo group (PG, n = 16) and the treatment group (TG, n = 18). From day 1 to day 14 of life, foals orally received 3 ml of either a probiotic preparation (1.05 × 109 CFU E. faecium and 4.50 × 108 CFU L. rhamnosus) or placebo (carrier) once a day. Faeces were collected directly from the rectum immediately after birth (meconium) and at day 14 and day 56 of life. Samples of 12 foals per group were selected for microbiological analysis. DNA was extracted and used for polymerase chain reaction–denaturing gradient gel electrophoresis (PCR‐DGGE) and quantitative PCR. No DNA or amplicons were obtained from meconium. There were no differences in richness of bands and Shannon index of diversity regarding the Clostridium cluster XIVa between groups. Cluster analysis and principal coordinate analysis of DGGE data showed a clear effect of age. Band‐based similarity of bacterial clusters (Dice coefficient) decreased from day 14 to day 56 of life (p < 0.001) in PG foals only resulting in lower similarity in PG versus TG foals when 2 month old (p < 0.01). Five of thirty re‐amplified bands were identified on species level. Others were assigned either to family (mainly Lachnospiraceae) or genus level (Akkermansia). The bands related to Akkermansia muciniphila or Akkermansia spp. appeared almost in all DGGE profiles. Two‐week supplementation of the probiotic preparation to foals had no significant impact on the composition of the faecal microbiota but it appears to have prevented the reduction of bacterial similarity between 2 and 8 weeks of age observed in not treated foals. 相似文献