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排序方式: 共有117条查询结果,搜索用时 140 毫秒
1.
A Lillehaug B Bergsj? J Schau T Bruheim T Vik?ren K Handeland 《Acta veterinaria Scandinavica》2005,46(1):23-32
Faecal samples were collected, as part of the National Health Surveillance Program for Cervids (HOP) in Norway, from wild red deer, roe deer, moose and reindeer during ordinary hunting seasons from 2001 to 2003. Samples from a total of 618 animals were examined for verocytotoxic E. coli (VTEC); 611 animals for Salmonella and 324 animals for Campylobacter. A total of 50 samples were cultivated from each cervid species in order to isolate the indicator bacterial species E. coli and Enterococcus faecalis/E. faecium for antibiotic resistance pattern studies. Salmonella and the potentially human pathogenic verocytotoxic E. coli were not isolated, while Campylobacter jejuni jejuni was found in one roe deer sample only. Antibiotic resistance was found in 13 (7.3%) of the 179 E. coli isolates tested, eight of these being resistant against one type of antibiotic only. The proportion of resistant E. coli isolates was higher in wild reindeer (24%) than in the other cervids (2.2%). E. faecalis or E. faecium were isolated from 19 of the samples, none of these being reindeer. All the strains isolated were resistant against one (84%) or more (16%) antibiotics. A total of 14 E. faecalis-strains were resistant to virginiamycin only. The results indicate that the cervid species studied do not constitute an important infectious reservoir for either the human pathogens or the antibiotic resistant microorganisms included in the study. 相似文献
2.
Masunda B Mutisi C Hamudikuwanda H Agumbah JG 《Tropical animal health and production》2002,34(4):309-318
The objectives of this study were to investigate the relationship between the concentrations of progesterone (P4) in the peripheral circulation and progestins in the faeces of cows in a smallholder farming area and to monitor the ovarian activity of such cows. The study was carried out in Sanyati smallholder farming area, located 250 km southwest of Harare. Blood and faecal samples for P4 and progestin determination, respectively, were obtained once a week from 35 Mashona type cows that belonged to farmers from three different villages. The cows were weighed once every month and all births were recorded. The concentrations of progestins in faeces and P4 in plasma were positively correlated (r = 0.72, p<0.01). Most of the non-pregnant cows (65%) cycled during the rainy season. Most of those that were acyclic at this time were undergoing post-partum anoestrus. During the dry season, most cows (58%) became acyclic as forage became scarce and of poor quality. Thirty-two calves were born during the study period, mostly during the first or last two months of the year, when there was enough forage. The mean calving to first oestrus in 14 cows that recalved was 71±49 days. Eight of these 14 cows conceived again, the calving to conception interval being 173±94 days. The cows' liveweights were highest in April, at the end of the rainy season. By the end of the dry season, the cows had lost, on average, 15% of their peak weight. 相似文献
3.
Whittington RJ Reddacliff LA Marsh I McAllister S Saunders V 《Australian veterinary journal》2000,78(1):34-37
OBJECTIVES: To determine the frequency of excretion of Mycobacterium avium subsp paratuberculosis in Merino sheep with Johne's disease and to quantify excretion in a group of Merino sheep. DESIGN: A pen and laboratory experiment. PROCEDURE: Seven sheep selected from an affected flock on the basis of acid-fast bacilli in the sheep's faeces were housed and total daily faecal output was collected, weighed and subjected to culture for M avium subsp paratuberculosis. An end-point titration method was used to enumerate viable M avium subsp paratuberculosis in a 15 day pooled sample from five sheep that had acid-fast bacilli in their faeces while housed. RESULTS: Four sheep with subclinical multibacillary Johne's disease excreted M avium subsp paratuberculosis each day for 11 days of cultural observation. A further three sheep were intermittent excreters but lacked other evidence of infection with M avium subsp paratuberculosis. The average number of viable bacteria excreted was 1.09 x 10(8) per gram of faeces while total daily excretion was 8.36 x 10(10) viable M avium subsp paratuberculosis per sheep. Examination of faecal smears stained with Ziehl Neelsen was an unreliable means of assessing daily excretion in individual animals except in those with severe lesions. CONCLUSION: Excretion of M avium subsp paratuberculosis in Merino sheep with multibacillary Johne's disease occurred daily, proving that environmental contamination can be continuous on farms with endemic ovine Johne's disease. Faecal culture is a useful method for detecting infection as it does not appear to be affected by the timing of collection of a sample from sheep with multibacillary disease however, to maximise the sensitivity of disease surveillance using faecal culture, sampling rates should be adjusted to take account of the proportions of multibacillary and paucibacillary cases. 相似文献
4.
给10头猪分别按体重5mg/kg单剂量内服和肌注恩诺沙星,采集自然排泄的猪粪、尿,用高效液相一荧光法测定恩诺沙星及其代谢产物环丙沙星浓度,计算采样间隔内单位时间药物排泄量占给药量的比例,比较2种不同给药途径原形药物和环丙沙星的排泄规律。结果显示,2种给药途径对恩诺沙星和环丙沙星总排泄量的影响不显著,仅对药物排泄量与时间之间的关系产生影响;2种给药途径的试验猪粪样中恩诺沙星的排泄量均高于尿样;内服与肌注给药后96h内,粪和尿中检出的环丙沙星分别占给药量的3.93%和4.02%,累积排泄的恩诺沙星和环丙沙星之和分别占给药量的9.89%(内服)和9.57%(肌注)。 相似文献
5.
Oliver Schneider Abdul K Amirkolaie Jordi Vera-Cartas Ep H Eding Johan W Schrama & Johan A J Verreth 《Aquaculture Research》2004,35(14):1370-1379
This study shows that alternatives for fishmeal in a fish diet affect not only fish growth but also faeces stability and nitrogen (N) and phosphorus (P) waste production. Wheat gluten diet (WGD), soybean meal extract diet (SBE), soybean meal diet (SBM), duckweed diet (DWD) and single‐cell protein diet (SCP) were evaluated as a fishmeal replacement on a 15% weight weight?1 basis in tilapia diets. Fishmeal replacement affected dry matter (dm), protein, ash and P digestibility significantly. Faeces recovery (6.8–11.2%) was not significantly affected, although the amount of non‐recovered faeces and total faeces showed significant differences. Duckweed diet and SCP resulted in the largest amounts of non‐recovered and total faeces (199–210, 224–225 g dm kg?1 feed dm). Compared with fishmeal diet (FMD), the WGD and SBE resulted in similar growth, but higher non‐faecal N losses (471–495 vs. 416 g N kg?1 N). Soybean meal diet, DWD and SCP resulted in lower growth but less non‐faecal loss (409–450 g N kg?1 N). The DWD and FMD had the highest N retention (480 g N kg?1 N) compared with the other diets (431–451 g N kg?1 N). Carbon retention, faecal and non‐faecal losses and P retention were similar for all diets (302–358, 142–176 and 489–523g C kg?1 C, 606–704 g P kg?1 P). Phosphorus faecal loss was lower for all diets (329–381 g P kg?1 P) than for the FMD (401 g P kg?1 P). 相似文献
6.
Abdolsamad K Amirkolaie Saber A El-Shafai Ep H Eding Johan W Schrama & Johan A J Verreth 《Aquaculture Research》2005,36(6):578-585
The need for unbiased digestibility estimation has led to the development of a number of faeces collection methods. However, there is still a large variation in apparent digestibility coefficient (ADC) of diet/ingredients between these methods. This study investigated the impact of dietary quality on ADC and faeces recovery measurements obtained by two faecal collection methods (Choubert and settling tank). The fish were fed five diets: a control diet as high‐quality diet, two levels of dried duckweed (20% and 40%) and two levels of fresh duckweed (20% and 40%), which were added to the control diet, as low‐quality diets. Apparent digestibility coefficient estimates were highly correlated (r>0.95) between both faecal collection methods. For all diets the ADC estimates were higher when using settling tanks compared with Choubert collectors. For the control diet differences in ADC between two collectors were small, but by inclusion of duckweed these differences increased. The recovery percentage of faeces was not correlated between both faecal collection methods (r=0.22, P=0.41). The estimated recovery percentage of faeces by settling tanks was about three times higher than by Choubert. In conclusion, the differences in ADC and faeces recovery measured by two faecal collection methods depend on diet quality. 相似文献
7.
S.M. Kristiansen M. Brandt E.M. Hansen B.T. Christensen 《Soil biology & biochemistry》2004,36(1):99-105
Analyses of the spatial and temporal variations in the natural abundance of 13C are frequently employed to study transformations of plant residues and soil organic matter turnover on sites where long continued vegetation with the C3-type photosynthesis pathway has been replaced with a C4-type vegetation (or vice versa). One controversial issue associated with such analyses is the significance of isotopic fractionation during the microbial turnovers of C in complex substrates. To evaluate this issue, C3-soil and quartz sand were amended with maize residues and with faeces from sheep feed exclusively on maize silage. The samples were incubated at 15 °C for 117 days (maize residues) or 224 days (sheep faeces). CO2 evolved during incubation was trapped in NaOH and analysed for C isotopic contents. At the end of incubation, 63 and 50% of the maize C was evolved as CO2 in the soil and sand, respectively, while 32% of the faeces C incubated with soil and with sand was recovered as CO2. Maize and faeces showed a similar decomposition pattern but maize decomposed twice as fast as faeces. The δ13C of faeces was 0.3‰ lower than that of the maize residue (δ13C −13.4‰), while the δ13C of the C3-soil used for incubation was −31.6‰. The δ13C value of the CO2 recovered from unamended C3-soil was similar or slightly lower (up to −1.5‰) than that of the C3-soil itself except for an initial flush of 13C enriched CO2. The δ13C values of the CO2 from sand-based incubations typically ranged −15‰ to −17‰, i.e. around −3‰ lower than the δ13C measured for maize and faeces. Our study clearly demonstrates that the decomposition of complex substrates is associated with isotopic fractionation, causing evolved CO2 to be depleted in 13C relative to substrates. Consequently the microbial products retained in the soil must be enriched in 13C. 相似文献
8.
9.
Isolation of faecal chlamydia from sheep in Britain andtheir characterization by cultural properties
Faeces samples were taken per rectum from sheep on 26 farms in England and Wales and examined for thepresence of chlamydia by culture McCoy cell monolayers. Thirteen of the fars were known to have had abortion outbreaks associated with Chlamydia psittaci (enzootic abortion) and 13 were free of this infection. The chlamydia isolated were characterized by cultural techniques. Chlamydia were isolated from the faeces of lambs on all 26 farms and the prevalence of infection varied from 5–50% on individual farms. There was no significant difference between the proportion of infected lambs on farms where enzootic abortion was present or absent. Lambs first showed infection when they were 3 months old and the prevalence rate of infection increased up to 9 months old. No chlamydia were isolated from the faeces of 316 adult ewes. The chlamydia were identified as enteric rather than abortion type and thus were C. pecorum rather than C. psittaci. 相似文献
10.
On farms where rats and mice are present, unprotected livestock feed may become contaminated with rodent faeces, thereby creating a possible source of infection for cattle and sheep. Livestock unable to avoid contaminated feed may choose to eat it entirely, reject it completely or attempt to reject faeces selectively while consuming some of the feed. Two experiments were conducted to investigate which of these three responses were demonstrated by livestock. Ten cattle and ten sheep were presented individually with three repeats of ten feed treatments. Treatments were based on two feed types (meal and pelleted compound), with three levels of contamination (none, 'low' and 'high'), from one of two rodent species (rat and mouse).Avoidance behaviour was greater for feed contaminated with rat faeces compared to feed contaminated with mouse faeces. At low levels of rat contamination there was evidence that livestock actively rejected faeces whilst consuming feed. At higher levels of contamination animals rejected faeces and feed. Livestock could not actively discriminate against mouse faeces and thus rejection of feed was used to avoid faeces ingestion.Despite rejection of contaminated feed and some discrimination against faeces, significant numbers of rodent faeces were ingested illustrating that livestock feeding behaviour cannot prevent ingestion of rodent faeces. Feed contaminated with rodent faeces therefore poses a significant risk of disease infection to livestock. 相似文献