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21.
An 80‐day feeding trial was conducted to evaluate the influence of different short‐term fasting and re‐feeding strategies on growth and physiological responses in yellowfin seabream, Acanthopagrus latus (2.4 ± 0.2 g) fingerlings. The fish were subjected to four different feeding regimes, and the control group fed four times daily to apparent satiation throughout the whole feeding period, while the other three groups were deprived for 2, 4 and 8 days followed by 8, 16 or 32 days of re‐feeding (F2R8, F4R16 and F8R32, respectively) in repeated cycles for 80 days. The fish in the control and F2R8 groups had the highest and the lowest total length, respectively (p < .05). Moreover, fish exposed to F4R16 had the highest hepatosomatic indices, while control fish had the lowest hepatosomatic indices (p < .05). Fish in the F2R8 group relatively had higher catalase and glutathione‐S‐transferase activities than other groups (p < .05). Furthermore, total protease, α‐amylase and alkaline phosphatase activities in the F4R16 and F8R32 were higher than the F2R4 and control groups (p < .05). Overall, this study showed that compensatory growth in weight and length and digestive enzyme activities were observed in the F4R16 and F8R32; however, the increase in the activity of antioxidant enzymes in the F8R32 group indicated that oxidative stress remained after 80 days of re‐feeding in the liver.  相似文献   
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To assess the contribution of starter lactic acid bacteria (LAB) to lipolysis in Cheddar cheese, the evolution of free fatty acids (FFAs) was monitored in Cheddar cheeses manufactured from pasteurized milks with or without starter. Starter-free cheeses were acidified by a combination of lactic acid and glucono-delta-lactone. Starter cultures were found to actively produce FFAs in the cheese vat, and mean levels of FFAs were significantly higher in starter cheeses over ripening. The contribution of nonstarter LAB toward lipolysis appears minimal, especially in starter-acidified cheeses. It is postulated that the moderate increases in FFAs in Cheddar cheese are primarily due to lack of access of esterase of LAB to suitable lipid substrate. The results of this study indicate that starter esterases are the primary contributors to lipolysis in Cheddar cheese made from good quality pasteurized milk.  相似文献   
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Following the introduction of a national abattoir-based monitoring programme for Salmonella in pigs, advisory visits were made to pig farms in England and Wales with high Salmonella seroprevalence assessed by muscle tissue fluid (meat juice) ELISA. Samples (n = 15 790), including pooled pen floor faeces (n = 12 136), were collected for Salmonella culture from 296 farms, between October 2003 and February 2008. Salmonella was isolated from 4489 (28%) of all samples collected, including 3301 (27%) of pooled pen floor faecal samples, from 270 (91%) of farms visited. Salmonella Typhimurium and S. Derby were the most prevalent serovars, representing 64% and 16% of isolates serotyped, respectively. The main phage types of S. Typhimurium identified were U288 and DT193. Antimicrobial resistance (AMR) was seen in 92% of isolates tested, with the highest frequencies of resistance occurring to tetracyclines (T), sulphonamide compounds (SU), ampicillin (AM), sulphamethoxazole/trimethoprim (SXT), streptomycin (S) and chloramphenicol (C). Fifty-nine AMR patterns were observed, the most frequent of these being T, AM, SXT, C, S, SU, seen in 35% of isolates tested. Multi-drug resistance was commonly found, with 67% of isolates submitted for AMR testing showing resistance to between four and nine antimicrobials.  相似文献   
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Alternatives to soil fumigation are needed for soilborne disease control. The aim of this study was to test anaerobic soil disinfestation (ASD) as an alternative to soil fumigation for control of critical soilborne pathogens in Californian strawberry production. Controlled environment experiments were conducted at 25 and 15 °C to test different materials as carbon sources for ASD using soil inoculated with Verticillium dahliae. Field trials were conducted in three locations comparing ASD with 20 Mg ha?1 rice bran (RB) against fumigated and untreated controls, steam, mustard seed meal and fish emulsion. In ASD‐treated soils, temperature and extent of anaerobic conditions were critical for control of V. dahliae, but multiple carbon inputs reduced inoculum by 80–100%. In field trials, ASD with RB provided control of a number of pathogens, and in three of four trials produced marketable fruit yields equivalent to fumigation. Little weed control benefit from ASD was found. ASD with RB also induced changes in the soil microbiome that persisted through the growing season. When equivalent yields were obtained, net returns above harvest and treatment costs with ASD RB were 92–96% of those with bed fumigation based on average prices over the previous 5 years. ASD can be a viable alternative for control of some soilborne pathogens. Growers are adopting ASD in California strawberry production, but research to determine optimal soil temperatures, anaerobicity thresholds and carbon sources for effective control of specific pathogens is needed.  相似文献   
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A real-time PCR was developed to detect Coxiella burnetii (the cause of Q fever) in ruminant placentas and aborted fetuses. Primer and probe sets previously developed for human tissue studies were used to target the insertion sequence IS1111 gene for C burnetii. The assay was highly sensitive, with a limit of detection of 10 copies of template, theoretically equating to a single bacterium, and did not cross-react with a panel of other bacteria. To determine sensitivity on field samples submitted for the diagnosis of abortion, results using the IS1111 PCR assay were compared with a com1 PCR assay. When applied to ruminant abortion material, including placental cotyledons and fetal samples, the IS1111 and com1 assays yielded positive results in 23 (25 per cent) of 93 and 19 (20 per cent) of 93 samples, respectively. One infected goat herd was monitored for 31 months: 57 (92 per cent) of 62 placental cotyledon samples from aborting and non-aborting goats, and 10 (30 per cent) of 33 fetal samples were positive by the IS1111 PCR assay.  相似文献   
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A commercial breeding colony of bearded dragons (Pogona vitticeps) experienced an increase in mortality that affected females only. Before death, the animals had lost appetite and weight, were dehydrated, and some had labored breathing. Necropsy revealed granulomas in many organs (ovaries, lungs, liver, kidneys, heart, bone marrow) in which numerous acid-fast bacteria were identified. Bacterial isolation confirmed Mycobacterium spp., which was identified by whole genome sequencing as closely related to the Mycobacterium ulcerans-marinum complex. Due to the zoonotic potential of this bacterium and the poor prognosis for the remaining sick animals, the entire colony was culled and 7 animals were evaluated. The possible routes for introduction of this bacterium, the female predisposition to the disease, as well as the zoonotic potential of this microorganism are discussed.Key clinical message:An atypical Mycobacterium species closely related to Mycobacterium ulcerans-marinum complex can cause high female morality in captive bearded dragons.  相似文献   
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