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81.
We substituted 10% of fishmeal with scallop (Argopecten ventricosus) or squid (Dosidiscus gigas) by‐product meal in a feed for shrimp (Litopenaeus vannamei) growth assay that lasted 60 days and then shrimps were submitted to handling stress. Shrimp fed the control diet had smaller weight gain and lower recovery after stress. Prostaglandins in gills were affected by diet and stress, with significant differences in shrimp fed the control diet before and after the stress. Hydroperoxides were increased after stress, while isoprostanoids were higher in shrimp fed the control diet. The gene expression of Glutathione peroxidase and Catalase was increased on the stressed shrimp fed the scallop diet, with no differences among diets for Superoxide dismutase or Cyclooxygenase. Arachidonic acid in the phospholipid fraction of muscle was the only fatty acid affected by stress and diet. Cholesterol oxidation products were significantly higher in shrimp fed the scallop diet compared to shrimp fed the control diet before applying the stress. A PCA analysis grouped in one‐factor growth variables, as well as Superoxide dismutase, esterified astaxanthin and isoprostane, while another factor was determined by stress, prostaglandin and hydroperoxide levels in gills. The partial substitution of fishmeal with scallop of squid by‐product meals affected growth and stress differently, indicating shrimp that grew up more were not necessarily more tolerant to handling stress, which can have a strong repercussion in aquaculture, particularly during density control, recording of growth and harvest.  相似文献   
82.
Every year fisheries discard >10 million tonnes of fish. This provides a bounty for scavengers, yet the ecological impact of discarding is understudied. Seabirds are the best‐studied discard scavengers and fisheries have shaped their movement ecology, demography and community structure. However, we know little about the number of scavenging seabirds that discards support, how this varies over time or might change as stocks and policy change. Here, we use a Bayesian bioenergetics model to estimate the number of scavenging birds potentially supported by discards in the North Sea (one of the highest discard‐producing regions) in 1990, around the peak of production, and again after discard declines in 2010. We estimate that North Sea discards declined by 48% from 509,840 tonnes in 1990 to 267,549 tonnes in 2010. This waste had the potential to support 5.66 (95% credible intervals: 3.33–9.74) million seabirds in the 1990s, declining by 39% to 3.45 (1.98–5.78) million birds by 2010. Our study reveals the potential for fishery discards to support very large scavenging seabird communities but also shows how this has declined over recent decades. Discard bans, like the European Union's Landing Obligation, may reduce inflated scavenger communities, but come against a backdrop of gradual declines potentially buffering deleterious impacts. More work is required to reduce uncertainty and to generate global estimates, but our study highlights the magnitude of scavenger communities potentially supported by discards and thus the importance of understanding the wider ecological consequences of dumping fisheries waste.  相似文献   
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The objective of this study was to examine all kick injuries to the radius and tibia seen in an ambulatory setting over an 11-year period in order to determine factors affecting outcome. Medical records of 51 horses seen for a kick injury to the radius or tibia were reviewed. Signalment, physical examination findings, type of management, and outcome were evaluated. There was a significant association between the presence of bony crepitus and a lameness score of ≥ 4/5 and a poor outcome. There was no relationship between signalment and outcome, but significantly more Thoroughbred/Thoroughbred cross horses were affected than any other breed. There was no detected relationship between the type of management and outcome; however, most (81%) horses were managed on stall rest. Horses with bony crepitus or with a lameness score of ≥ 4/5 were at an increased risk for euthanasia.  相似文献   
86.
A method is described for the rapid and sensitive assay of phagocytosis that utilizes radioactively labelled bacteria. With this method, we observed that phagocytosis of heat-inactivated Aeromonas salmonicida by leukocytes isolated from gut of rainbow trout fed with different viable probiotics (Lactococcus lactis subsp. lactis, Lactobacillus sakei, and Leuconostoc mesenteroides) was significantly higher (P<0.05) after 2 weeks of probiotic-feeding than the control group. However, only phagocytosis of live A. salmonicida by the leukocytes isolated from gut of rainbow trout fed with L. lactis subsp. lactis was significantly higher (P<0.05) than the control group.  相似文献   
87.
The potential of a new kind of light-induced pesticide action was evaluated for a broad variety (32) of natural photosensitizers and their thione derivatives. The latter were synthesized to shift the absorption spectra towards the visible region and to increase the triplet and singlet oxygen quantum yields. Qualitative and quantitative evaluation of growth inhibition of Fusarium culmorum (F. G. Smith) Sacc. produced by these photosensitizers under UVA and visible light was performed on silica gel plates and in liquid medium. The results show that the phototoxicity per excited molecule of the thione derivatives using UVA light was similar to that of their parent natural compounds. On the other hand, only the thione derivatives were photoactive under visible light irradiation. These compounds show encouraging levels of phototoxicity against F. culmorum, both in liquid culture and on silica plates, and may have potential for use as photoactive pesticides.  相似文献   
88.
A 4-year-old, castrated, male domestic ferret (Mustela putorius furo) was evaluated for a possible upper respiratory tract infection and wheezing for approximately 3 weeks. Supportive care for a suspected upper respiratory tract infection was initiated; however, the patient became progressively more dyspneic over the next 48 hours. A possible tracheal mass was identified upon thoracic radiographic imaging of the ferret. Tracheoscopy and a computed tomography scan of the neck and thorax confirmed the presence of a tracheal mass approximately 3 cm from the larynx obstructing 80% of the tracheal lumen. Rather than pursuing surgical resection, the owners elected humane euthanasia. An adenosquamous carcinoma of the trachea was diagnosed after histologic analysis. This tumor type has been diagnosed in the lungs of ferrets that were experimentally exposed to carcinogens found in cigarette smoke; however, there are no previous reports of this or any other tumor type associated with the ferret trachea. A tracheal mass causing a partial upper airway obstruction should be considered within the differential disease diagnosis list when a ferret is presented with dyspnea.  相似文献   
89.
Phosphorous (P) and nitrogen (N) residuals from Litopenaeus vannamei and N and P retention by L. vannamei were studied at three protein levels and with two protein sources: fish meal with plant protein (AVD) and plant protein with squid meal as an attractant (VD). A protein retention bioassay began with shrimp that were 1.5–2.5 g, and nutrient release bioassays were conducted with shrimp of two sizes (4.5 and 8.5 g). Both bioassays were conducted at: 30 ± 0.5°C, [O2] > 4 mg L?1, and 38 UPS. Total P residuals were significantly higher for AVDs than for VDs (< 0.05), particularly those with a high dietary protein level. The particulate P fraction was the predominant form of P. Total N and inorganic dissolved N, mainly in ammonia form, significantly increased (< 0.05) with dietary protein level and shrimp size, regardless of the protein source. VDs resulted in significantly greater P retention (< 0.05) than AVDs, without significantly affecting growth rates or survival. P retention as well as N retention decreased with increasing protein supplementation level, independently of the protein source used (> 0.05). This study shows that the substitution of fish meal with plant protein (soybean meal and wheat flour) improves P retention in L. vannamei.  相似文献   
90.
This study evaluated onset and incidence of palmar process fractures in foals and investigated corresponding changes in hoof conformation. Radiographs of 17 warmblood foals were taken at 1 week and at 2, 4, 6, 8, and 12 months of age and examined for evidence of palmar process fractures. Hoof parameters were measured from the radiographs, and comparisons were made between fractured and nonfractured feet. All foals suffered at least one fracture during the study period, with an average age of 3.68 ± 0.20 months at fracture occurrence. Hoof conformation and fracture occurrence were not significantly correlated. Foals consistently demonstrated higher lateral heights in the right foot and higher medial heights in the left foot. Hoof angle increased until 3 months of age and then gradually dropped. Hoof-pastern axis exhibited a broken forward conformation, but approached a more correct conformation by 12 months of age. There was a significant reduction in variation of variables for hoof and pastern angle in both feet, and hoof-pastern axis in the right foot. Hoof conformation does not appear to be a causative factor of palmar process fractures. It is possible that these fractures are a normal part of bone remodeling.  相似文献   
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