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1.
Composting of beef cattle manure using sawdust or recycled compost as a bulking agent was investigated for the management of clopyralid risk, such as changes in the clopyralid concentration and the mechanism of clopyralid accumulation caused by recycled compost. These raw materials were composted with laboratory equipment, which was controlled at 60℃ after the temperature peak by autothermal composting. Clopyralid concentration did not changed during composting in the thermophilic phase; on the contrary, it increased because clopyralid accumulated in compost when recycled compost was used repeatedly as a bulking agent. The clopyralid accumulation ratio (ratio of clopyralid concentration to that in the first compost) could be explained by a model using a recurrence formula, and a correlation existed between the calculated (model) accumulation ratios and measured accumulation ratios (R2 = 0.78). Using this model, the excessive accumulation of clopyralid could be controlled when using recycled compost as a bulking agent with lower moisture content or when part of the recycled compost was replaced by another bulking agent, even if recycled compost had high moisture content. In future work, the model and its considerations should be verified in a field test.  相似文献   

2.
The production and partial characterization of bacteriocin‐like substances (BLSs) produced by bacteria isolated from cow manure compost were investigated. Eight BLS producers, which exhibited inhibitory activity against pathogenic bacteria, were isolated from cow manure compost at different stages of the composting process. The pile temperature ranged from 9.1°C to 73.2°C. The BLSs showed thermostability, but the BLS producers were not thermostable except for the H1 producer. Thermophilic Bacillus licheniformis H1 was further characterized. The culture supernatant of B. licheniformis H1 exhibited antagonistic activity against various species of Gram‐positive bacteria such as Listeria monocytogenes ATCC19111 but not against Gram‐negative bacteria except Pseudomonas fluorescens ATCC11251. Inactivation of bacteriocin‐like activity by α‐chymotrypsin, trypsin, and papain was highly significant (P < 0.001). The BLS was found to be stable under a pH range from 3 to 9 and at temperatures up to 75°C for 60 min, but it lost activity after being autoclaved at 121°C for 15 min. The optimum production of BLS by B. licheniformis H1 was obtained at a temperature of 55°C. Sodium dodecyl sulfate – polyacrylamide electrophoresis analysis of concentrated partially purified supernatants collected after resting the bacterial cells at 55°C revealed a bacteriocin‐like protein with a molecular mass of approximately 3.5 kDa. This study is the first report of a BLS from thermophilic B. licheniformis with an animal compost origin.  相似文献   

3.
肉牛粪污中纤维素降解菌的分离筛选   总被引:1,自引:0,他引:1  
为了获得有效降解肉牛粪污中纤维素的细菌,采用以羧甲基纤维素钠为碳源的方法对牛粪及其自然堆肥样品进行纤维素降解菌的分离,对已分离菌株进行形态学和分子生物学鉴定,再结合纤维素刚果红水解圈测定和滤纸条降解试验做进一步研究。结果表明,以羧甲基纤维素钠为碳源,初步分离得到牛粪样品及堆肥中32株纤维素降解菌,进一步筛选得到有刚果红水解圈菌株4株,分别为XQ-1、XQ-2、XQ-3、XQ-4,其对滤纸条具有一定的降解能力,经16S rDNA鉴定,4株菌株分别为大肠埃希菌(Escherichia coli)、黏质沙雷菌(Serratia marcescens)、雷氏普罗威登斯菌(Providencia rettgeri)和费格森埃希菌(Escherichia fergusonii)。  相似文献   

4.
To determine the full potential of the compost worm Eisenia fetida as waste processor and as source of protein, the life-cycle of this species had to be studied thoroughly. The development, growth and reproduction of Eisenia fetida were studied on cattle manure under favourable conditions of moisture, temperature and nutrition. Data were gathered over a period of 600 days. Apart from the life-cycle this study also indicated that this species can be reproductively active for more than 500 days. This is significantly longer than had previously been believed. Each cocoon produced a mean of 2,7 hatchlings after a mean incubation period of 23 days. These worms attained sexual maturity after 40 to 60 days and produced their first cocoons within four days after mating took place.  相似文献   

5.
随着我国肉(奶)牛养殖的规模化、集约化发展,牛粪高效、安全的利用成为当前发展现代农业和环境保护急需解决的重要问题。本文对照牛粪发酵参数,重点介绍了牛粪堆肥发酵的控制和调节,以及堆肥产物的质量评判标准,旨在为该领域的研究提供理论参考。  相似文献   

6.
Background Queensland has the highest incidence of Q fever in Australia. The aim of this study was to undertake a cross‐sectional seroprevalence survey of Coxiella burnetii, the causative agent of Q fever, in beef cattle in Queensland. Methods Serum samples were tested by ELISA for both phase II and phase I antigens of the organism using an Australian isolate. Blood samples were collected at an abattoir that processes beef cattle originating from northern and north‐western Queensland, in addition to blood samples taken from beef cattle across Queensland as part of a second survey. Results Seropositivity was 16.8% (95% confidence interval 16.7–16.8%). Conclusion Evidence of C. burnetii infection in beef cattle has public health implications for occupational exposure of primary producers and veterinarians and for the proximity of beef cattle properties to residential areas in regional Queensland. This study is the first known investigation of C. burnetii seroprevalence in beef cattle in Queensland and the first known use of an Australian C. burnetii isolate for screening using both phase II and phase I antigens.  相似文献   

7.
Groups of l8-month-old cattle were inoculated intratracheally with 5 X 105 colony forming units (high dose) or 500 colony forming units (low dose) of Mycobacterium bovis to determine an appropriate dose to induce lesions similar to those seen in the natural disease. An additional group of 21–28 weeks pregnant cattle were inoculated with the high dose of M. bovis to determine if pregnancy increased the susceptibility of cattle to M. bovis infection. By 23–24 weeks after challenge, the high dose of M. bovis had induced extensive lung lesions, and tuberculous lesions were observed in the lymph nodes of the head, neck, and thoracic and abdominal cavities. In contrast, the low dose of M. bovis induced predominantly small lesions (< 1 cm diameter) which were localised to the lungs and pulmonary lymph nodes. The lesions induced by the low dose were similar to those seen in the natural disease in cattle. The majority of the high dose group cattle produced strong antibody responses to M. bovis culture filtrate, while only one low dose animal produced a detectable response. All of the M. bovis-inoculated cattle produced strong cellular immune responses to bovine PPD (skin test and interferon-γ responses). Pregnancy did not appear to affect the susceptibility to M. bovis infection, and immune responses of the cattle in this group at the end of the study were similar to those in the high dose non-pregnant group. However, from the first test after calving, the interferon-y responses of peripheral blood cultures to bovine PPD were low compared with the responses prior to calving.  相似文献   

8.
The preliminary study was conducted to assess the virulence of a strain of Brucella abortus (1969D) and to compare the susceptibility of water buffalo and cattle calves to infection by the intraconjunctival route. Seven of each cattle and water buffalo (Bubalus bubalis) calves aged 3–6 months were inoculated intraconjunctivally with counts ranging from 1.5 × 107 to 1.7 × 1010 colony forming units of B. abortus. Animals were monitored over an 8-week period for clinical manifestations and serological and hematological evidence of infection. At slaughter, eight lymph nodes from each animal were sampled for bacteriological and histopathological assessments. Lymph nodes from three water buffalo (43%) and five cattle (71%) yielded B. abortus (P = 0.048). Parotid/prescapular lymph nodes were most sensitive in detecting B. abortus. Our data suggest that B. abortus strain 1969D may be used as challenge strain, and water buffalo appeared to have a lower susceptibility to B. abortus infection than cattle.  相似文献   

9.
A study was conducted to determine the safety and feasibility of using municipal solid waste compost (MSWC) as a bedding material for cattle feedlots. Two pens in an open-front pole barn were bedded with either corn stalks or MSWC in each of two feeding periods (blocks) with two pens (23 x 34 m) per block. Block 1 used 336 heifers (initial BW, 398 kg) during a 104-d period (summer), and Block 2 used 276 steers (initial BW, 412 kg) during a 92-d period (winter). Blood concentrations of regulated elements (Cd, Cu, Mo, Pb, Ni, and Zn), electrolytes, glucose, or liver and kidney enzymes were unaffected (P > .05) by use of either bedding material. Polychlorinated biphenyls in perirenal fat were not detectable (< .5 ppm) in cattle bedded with either material. At slaughter, kidney Cu and kidney and liver Pb concentrations were greater (P < .05) for cattle bedded with MSWC. Despite this, tissue concentrations of these elements were well within those considered normal for healthy cattle. Regulated element concentrations of feed did not differ (P > .05) between diets within period, and neither did DMI or DM digestibility; therefore, cattle bedded with MSWC were likely inhaling additional amounts of these elements and excreting them through feces. More MSWC than corn stalks was required to supply a dry bed per animal daily (P < .05). Soiled bedding (manure as-is) output was similar (P > .05) for both bedding materials. On a DM basis, more manure (P < .05) was removed from the pen bedded with MSWC in Block 2. Total manure N and P removed was similar for both bedding materials. Nitrogen and P concentrations in manure were lower (P < .05) during Block 2, but total manure N removed was greater (P < .05) during Block 2. Total manure P removed from the pens was not affected by season. Under the conditions of this study, MSWC seemed to be a safe and effective bedding material for cattle feedlots.  相似文献   

10.
The present study was carried out to assess the prevalence of motile Aeromonas spp. in the faeces of clinically healthy sheep, cattle and horses and evaluate their susceptibility to some anti-microbial agents. Rectal swabs from 120 sheep, 85 cattle and 20 horses were examined for Aeromonas species using alkaline peptone water (pH 8.4) as the enrichment medium and Aeromonas Selective Agar containing 5 mg/l ampicillin as the isolation medium. Identification and antibiotic resistance of motile Aeromonas strains was performed using Gram Negative Enteric ID panel. Motile aeromonads were isolated from 12 (10%) sheep, 7 (8.2%) cattle and 1 (5%) horse. Of these 20 aeromonad isolates, 13 were A. caviae, 6 were A.sobria and 1 was A. hydrophila. Aeromonas species in the faeces of livestock might pose a public health problem for humans who are in direct contact with contaminated animals. However, further studies should be performed on aeromonads relating to their transmission between animals and humans.  相似文献   

11.
Gassericin A (GA) is a circular bacteriocin produced by Lactobacillus gasseri LA39. In this study, GA‐containing concentrate was prepared using a cross‐flow membrane filtration device (30 kDa cut‐off) from the culture supernatant of Lb. gasseri LA39 cultivated in a cheese whey‐based food‐grade medium. The bacteriocin activity titer in the concentrate was 16 times as high as that of the culture supernatant and was completely maintained through each incubation at 4°C for 3 months, 37°C for 2 months, 60°C for 5 h, and 100°C for 30 min. The GA‐containing concentrate was used with glycine powder to make custard creams, and then four representative strains of custard cream spoilage bacteria (Bacillus cereus, Lactococcus lactis subsp. lactis, Achromobacter denitrificans and Pseudomonas fluorescens) were individually inoculated at c. 103 colony forming units/g in the custard creams. Throughout 30 days of incubation at 30°C, all of the inoculated bacteria were completely inhibited by the combination of 5% (w/w) of the GA‐containing concentrate and 0.5% (w/w) glycine. This is the first highly practical application of GA to foods as a biopreservative, and the concentration method and the bacteriocin concentrate would contribute to biopreservation of several foods.  相似文献   

12.
Brucella melitensis biovar 1 was isolated from bovine milk samples from a herd in central Kenya, and Brucella abortus biovar 3 was isolated from aborted fetus materials and vaginal discharge fluids from cattle in central and eastern provinces of Kenya. All infections including those with B. melitensis were in cattle with reproductive problems kept in mixed herds indicating that cross infection occurs from small ruminants. Multiple-locus variable-number tandem repeat analysis genotyping revealed a close molecular homology of the B. melitensis isolates with an isolate from Israel and a close homology of the B. abortus isolates with an isolate from Uganda indicating that these genotypes have a wide geographic distribution. Infection of cattle with B. melitensis may complicate the control of brucellosis in this country.  相似文献   

13.
The occurrence of generic Escherichia coli, E. coli O157, Salmonella, and Campylobacter in cattle manure, beef carcasses, catch basin water, and soils receiving manure application was determined in 21 Alberta feedlots. In cattle manure, generic E. coli (98%, 2069/2100) and Campylobacter (76%, 1590/2100) were frequently detected; E. coli O157 (7%, 143/2100) and Salmonella (1%, 20/2100) were less frequently detected. Samples from beef carcasses in the cooler following Hazard Analysis Critical Control Point interventions yielded only 1 isolate each of generic E. coli and Campylobacter (1/1653) and no Salmonella (0/1653). Catch basin water specimens were positive for generic E. coli in both the spring (62%, 13/21) and the fall (52%, 11/21). Other bacteria were detected only in the spring water specimens, including E. coli O157 (29%, 6/21), Salmonella (5%, 1/21), and Campylobacter (52%, 11/21). Generic E. coli was frequently isolated from soil specimens (30%, 27/88), but E. coli O157 was not found in soil samples obtained in the spring and was only occasionally detected in the fall samples (9%, 3/32). Salmonella were occasionally found in the soil specimens collected in the spring (3%, 2/56), but not in the fall season (0/32). Campylobacter jejuni was frequent in cattle manure (66%, 1070/1623), but rare in carcass and environmental samples. E. coli O157 and Salmonella were rarely detected in cattle or the environment. Generic E. coli and Salmonella were rarely detected on carcasses.  相似文献   

14.
A total of 26 samples of Matsoni were collected in Georgia. From these samples 80 strains of lactic acid cocci and 173 strains of lactobacilli were isolated. The number of lactic acid bacteria varied between 105 and 1010 colony forming unit (CFU)/mL. All the isolated lactic acid bacteria were thermophilic bacteria that could grow at 45°C. The predominant lactic acid bacteria were Streptococcus thermophilus and Lactobacillus delbrueckii spp. bulgaricus in 25 samples of Matsoni, while Lactobacillus helveticus was also a predominant species, together with the two previous species in one sample of Matsoni. We showed there was diversity in both S. thermophilus and L. delbrueckii spp. bulgaricus at the strain level by randomly amplified polymorphic DNA analysis.  相似文献   

15.
Objective To perform a comprehensive phenotypic characterisation of 35 isolates of bacteria previously identified as haemolytic Pasteurella‐Actinobacillus and obtained from cattle and sheep. Design The 35 isolates that had been obtained from Australian animals, 30 from cattle and five from sheep, were compared with reference strains of the five recognised species of the genus MannheimiaM haemolytica, M glucosida, M granulomatis, M ruminalis and M varigena. Results Thirty‐four of the isolates could be confidently assigned to three species of the genus Mannheimia. Twenty‐nine were M haemolytica, with 25 being isolated from cattle and four from sheep. All but three of the bovine M haemolytica were isolated from pneumonic lungs. Of the three remaining bovine M haemolytica isolates, one was obtained in pure culture from a bovine milk sample and the other two as part of a mixed flora associated with a middle ear infection of a calf suffering mucosal disease. Of the four ovine M haemolytica isolates, two were isolated in pure culture from milk and two, also in pure culture, from pneumonic lungs. Three bovine isolates were identified as M granulomatis ‐ one from a tongue abscess, one from a jaw abscess and one from a lung showing suppurative bronchopneumonia. Two bovine isolates were identified as M varigena‐ one coming from an udder and the other from a spleen. The available diagnostic records provided no information on whether these isolates were associated with a disease process. The remaining isolate was obtained from an ovine tongue abscess and could not be assigned to a recognised species within the genus Mannheimia. Conclusion The study represents the first time that M haemolytica, M granulomatis and M varigena have been recognised as being present in cattle and sheep in Australia. Veterinary laboratories that encounter Pasteurella‐Actinobacillus‐like organisms from cattle and sheep should attempt as complete a characterisation as possible to help improve our knowledge of the disease potential of these organsims.  相似文献   

16.
Tuberculosis concurrent infection in cattle and their respective owners in North‐western Ethiopia had been investigated. Two hundred and ten cattle owners and 1220 heads of their cattle were included in the study to determine degree of tuberculosis infection in cattle owned by tuberculosis patients and tuberculosis patients. Comparative intradermal tuberculin test, bacteria culturing, acid fast staining and biochemical tests were used to conduct the study. The prevalence of tuberculosis was significantly (P < 0.001) higher in cattle owned by tuberculosis patients than in cattle owned by non‐tuberculosis owners, and infection with tuberculosis was threefold greater in cattle owned by tuberculosis‐positive owners. Further more, cattle owners who consumed raw milk were at higher risk (P < 0.001, OR = 3.23) for tuberculosis infection than those who consumed boiled milk. Mycobacterium tuberculosis (15.4%), Mycobacterium bovis (44.1%) and atypical mycobacteria (38.5%) were identified from milk collected from tuberculin‐positive cows using biochemical tests. Similarly M. tuberculosis (74.5%), M. bovis (14.9%) and atypical mycobacteria (8.5%) were identified from sputum and fine needle aspiration specimens of tuberculosis patient cattle owners. Mutual transmission of mycobacterium from animals to humans and vice versa has been signified.  相似文献   

17.
AIM: To discover whether cross infection between red deer (Cervus elaphus) and cattle is possible with either a bovine isolate of the cattle lungworm, Dictyocaulus viviparus, or with a cervine isolate of the lungworm, Dictyocaulus eckerti.

METHOD: Twelve cattle and 12 red deer were reared parasitefree from birth. At 3–4 months of age, half of each group (n=6) were experimentally infected with D. viviparus and the other half with D. eckerti. The course of infection was monitored for 34 days, after which the animals were slaughtered and the lungs removed to assess levels of infection.

RESULTS: Faecal larval counts demonstrated that patent Dictyocaulus infections occurred in all groups. At necropsy, adult worms were found in the lungs in all groups except the cattle that were infected with D. eckerti. The largest numbers of adult worms were found in the lungs of the red deer infected with D. eckerti.

CONCLUSION: It was demonstrated that both cattle and red deer could be infected with either D. viviparus or D. eckerti. However, D. eckerti larvae that originated from deer established more successfully in deer and D. viviparus larvae that originated from cattle established more successfully in cattle.  相似文献   

18.
An isolate Enterococcus hirae was used to determine its pathogenicity for chicken embryos and for chicks treated with betamethasone. E hirae was inoculated intravenously into four-day-old chicks which had been treated for three consecutive days with betamethasone, and chick embryos were inoculated into the allantoic cavity with 102 and 103 bacteria. E hirae was not pathogenic for the chicks or for the embryos.  相似文献   

19.
The bacterial load and degree of antibiotic resistance present in untreated and antibiotic‐treated semen samples were investigated in five bulls standing at a cattle‐breeding centre. Bacterial load was determined by colony counts from semen samples cultured on brain heart infusion and nutrient agar plates. Antibiotic resistance in these bacteria was assessed by measuring the diameter of bacterial growth inhibition zones around discs containing different concentrations of antibiotics. Representative antibiotic‐resistant bacterial isolates were selected for identification. Untreated semen contained few culturable bacteria, and all were completely sensitive to gentamycin, spectinomycin and lincomycin: six of the isolates showed some resistance to tylosin. In semen to which antibiotics had been added as part of the routine production process, two isolates were sensitive to all of the antibiotics tested, and the remainder were resistant to all. Resistant Gram‐negative isolates that were identified included Pseudomonas and Stenotrophomonas spp. both in the class Gammaproteobacteria and a Sphingomonas sp. which is in the class Alphaproteobacteria.  相似文献   

20.
Horse manure management is becoming a major concern in suburban areas of the United States. An average horse can produce eight to ten tons of manure per year, accumulating at a rate of two cubic feet per day, including bedding. If properly composted, the manure and bedding can be transformed into a very useful, odorless, pathogenfree product. The objective of this trial was to compare the characteristics of recycled chopped phone book paper, sawdust and wheat straw bedding during composting. Six horses were stalled on three bedding types: recycled phone book paper, sawdust and straw. Each day manure and soiled bedding types were separately collected and transported to compost sites over an eight-day period. Three compositing bins were each hand constructed from wooden pallets with 10 cm slats. The front of the bin was left open for manipulation of materials during the composting process. Initial volumes of the soiled bedding materials were 1m3, 1m3, and 1.5m3 for paper, sawdust and straw, respectively. Temperatures were taken for each bedding materials using a 51 cm REOTEMP compost thermometer. Temperatures were taken on Day 0 and every four days over the 65-day trial (n=52). Temperature was used to determine the need for moisture addition and aerating by turning to keep the piles microbially active. On Day 37 the C:N ratio was adjusted by the addition of ammonium sulfate, 0.1 kg, 0.1 kg and 0.14 kg for sawdust, phone book paper and straw piles, respectively. Mean standard error and range for compost temperatures (C) were: phone book paper, 33.17±10.33 (13–52); sawdust, 45.6±9.35 (27–58); straw, 30.42±6.57 (16–39). The sawdust composted more readily as compared to the phone book paper or straw. The paper and straw had poorer structure, which caused compaction of the material when moistened; thus, porosity, oxygen supply and microbial activity were reduced.  相似文献   

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