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101.
Invertebrate meals (e.g. polychaetes and insects) present novel and sustainable high‐quality nutrient sources for use in fish feed formulations. To test this innovative source, an eleven‐week feeding trial was conducted evaluating the effects of replacing the fishmeal (FM) component as an example of a superior protein source (FM CTRL) with ragworm meal (RW, Nereis virens) and/or silkworm pupae (SWP, Bombyx mori) in mirror carp (Cyprinus carpio) diets. Three experimental diets with partial replacement of FM (diets: RW + FM, SWP + FM and RW + SWP + FM) were formulated. All diets were formulated to be iso‐nitrogenous, iso‐lipidic and iso‐energetic. Growth performance and feed utilization indices were assessed, and the feeding trial concluded with the analysis of haematological parameters to provide an indication of carp physiological and health status. Mean weight gain was greatest in mirror carp fed RW + FM (60.83 fish?1 day?1; P < 0.05 vs. all other diets) followed by SWP + FM (40.62 g fish?1 day?1; P < 0.05 vs. all other diets). The least weight gain was achieved in fish fed FM + SWP + RW+ and FM CTRL (34.34 and 33.96 g fish?1 day?1, respectively; not significantly different from each other). Fish fed on RW + FM diet had significantly lower plasma ammonia concentrations than any other dietary groups (= 0.04). Mirror carp fed on SWP + FM diet (111.52 units mL?1) were observed to have a marked enhancement in alternative complement activity than FM CTRL (79.21 units mL?1, = 0.041). Both ragworm and silkworm pupae meal present attractive sustainable functional feed component in carp diets, with benefits on enhancing growth performance and specific physiological parameters.  相似文献   
102.
The pattern of sulfur transformation in peat across the Everglades basin indicates that pyrite formation in organic-rich swamps depends on the use of organic oxysulfur compounds in dissimilatory respiration by sulfur-reducing bacteria. This paragenesis explains the primary distribution of sulfur compounds in low-sulfur coals and possibly in most coals and many organic-rich soils and sediments. It also accounts for the occurrence of framboidal pyrite bound in fossil tissue in coal and sediments.  相似文献   
103.
Objective— To determine differences in bacterial strike-through for materials commonly used to cover the distal aspect of the pelvic limb during operative site preparation.
Study Design— Randomized block design; ex vivo model.
Animals— Canine cadaveric pelvic limbs (n=40).
Methods— Pelvic limbs (n=40) were randomly assigned to 4 treatment groups: Group 1=Vetrap+sterile Coban; Group 2=latex glove+Vetrap+sterile Coban; Group 3=latex glove+Vetrap+sterile Coban+sterile latex glove+sterile Coban; and Group 4=latex glove+Vetrap+sterile disposable drape+sterile Coban. Limbs were contaminated with a standardized bacterial solution and routinely prepared using the assigned distal leg wrap. Bandages were fluid challenged with a saline (0.9% NaCl) solution-soaked laparotomy sponge for 30 seconds. The wrap surface was sampled for microbial culture before surgical preparation, immediately after, and 60 minutes after applying a sterile leg wrap.
Results— Bacterial growth occurred in all Group 1 cultures, 90% of Group 2 cultures, and none of the Group 3 and 4 cultures, 60 minutes after applying the sterile wrap.
Conclusion— A distal leg wrap of Vetrap+sterile Coban is not effective in preventing bacterial strike-through.
Clinical Relevance— If similar results occur in the live animal, then a sterile impermeable barrier must be incorporated into the distal leg wrap to prevent bacterial strike-through.  相似文献   
104.
OBJECTIVE: To compare the microstructural damage created in bone by pins with lathe-cut and rolled-on threads, and to determine the peak tip temperature and damage created by positive-profile external fixator pins with either hollow ground (HG) or trocar (T) tips during insertion. STUDY DESIGN: An acute, in vitro biomechanical evaluation. SAMPLE POPULATION: Twenty-seven canine tibiae. METHODS: Lathe-cut thread design with T point (LT-T), rolled-on thread design with T point (RT-T), and rolled-on thread design with HG point (RT-HG) pins were evaluated. Twenty pins of each type were inserted under constant drilling pressure into 12 canine tibiae (12 diaphyseal and 8 metaphyseal sites per pin type). Peak pin tip temperature, drilling energy, end-insertional pin torque, and pullout force were measured for each pin. For the histologic study, five pins of each type were inserted into cortical and cancellous sites in 15 additional tibiae. Entry and exit damage, and thread quality were assessed from 100 micron histologic sections by using computer-interfaced videomicroscopy. RESULTS: T-tipped pins reached higher tip temperature in both diaphyseal and metaphyseal bone compared with HG-tipped pins. RT-T pins had higher pullout strength (diaphyseal) and end-insertional torque compared with other combinations. No differences in drilling energy or insertional bone damage was found between the three pin types (P < .05). CONCLUSIONS: T-tipped pins mechanically outperformed HG-tipped pins. Pin tip and thread design did not significantly influence the degree of insertional bone damage. CLINICAL RELEVANCE: T-tipped pins may provide the best compromise between thermal damage and interface friction for maximizing performance of threaded external fixator pins.  相似文献   
105.
Forest fungi not only have important functions within the forest ecosystem, but picking their fruit bodies is also a popular past time, as well as a source of income in many developing and developed countries. The expansion of commercial harvesting in many parts of the world has led to widespread concern about overharvesting and possible damage to fungal resources. In 1975, we started a field research project to investigate the effects of mushroom picking on fruit body occurrence. The three treatments applied were the harvesting techniques picking and cutting, and the concomitant trampling of the forest floor. The results reveal that, contrary to expectations, long-term and systematic harvesting reduces neither the future yields of fruit bodies nor the species richness of wild forest fungi, irrespective of whether the harvesting technique was picking or cutting. Forest floor trampling does, however, reduce fruit body numbers, but our data show no evidence that trampling damaged the soil mycelia in the studied time period.  相似文献   
106.
107.
The role of inland fisheries in livelihoods, food security and sustainable development is often overshadowed by the higher profile interest in ocean issues. Whilst inland fisheries' catch and contribution to global nutrition, food security and the economy, are less than that of marine fisheries, global‐level comparisons of fish production obscure considerable livelihood impacts in certain countries and sub‐national areas. To highlight these contributions, this paper synthesizes recent data and innovative approaches for assessing such livelihood contributions and their importance in countries with limited access to ocean resources and aquaculture. Inland fisheries are crucial for many socially, economically and nutritionally vulnerable groups of people around the world, but the challenges in monitoring inland fisheries preclude a complete understanding of the magnitude of their contributions. This situation is rapidly improving with increasing recognition of inland fisheries in development discourses, which has also encouraged research to enhance knowledge on the importance of inland fisheries. We review this work, including collated information published in a recent Food and Agriculture Organization report, to provide an up to date characterization of the state of knowledge on the role of inland fisheries.  相似文献   
108.
The aim of this study was to determine the frequency of carriage of methicillin-resistant Staphylococcus pseudintermedius (MRSP) among dogs admitted to a small animal hospital during a 17-month period, to characterize these isolates and to initially screen for possible factors associated with MRSP carriage. Swabs were taken from the nose/pharynx and the perineum as well as from wounds and skin infections (if present) of 814 dogs before entering the small animal hospital. A questionnaire for background information was completed. The staphylococcal species and methicillin resistance were confirmed pheno- and genotypically. The identified MRSP isolates were characterized by SCCmec typing, testing for susceptibility to 25 antimicrobial agents and SmaI-directed pulsed-field gel electrophoresis. A first screening for possible risk factors for MRSP carriage was performed by means of unifactorial contingency tables and CART analysis. Sixty (7.4%) dogs were positive for MRSP. All MRSP isolates harboured a type II-III SCCmec cassette and showed extended resistance to antimicrobial agents. Fifteen different SmaI patterns were observed. The major factors that clustered with MRSP carriage were former hospitalization and antibiotic treatment within the last six months before sampling. This study showed that only a minor part of the sampled dogs carried multi-resistant MRSP isolates. The facts that prior hospitalization and/or antibiotic therapy are potential associated factors for MRSP carriage underline the necessity of a judicious use of antibiotics in small animal medicine.  相似文献   
109.
110.
Flamingos are filter feeders that only rarely ingest larger food items. Their bill anatomy is adapted to the suction, filtration, and ejection of a fluid medium. This case report documents a rare case of bill impaction in a group of Caribbean flamingos (Phoenicopterus ruber) that were kept in a mixed exhibit together with roseate spoonbills (Platalea ajaja) and scarlet ibis (Eudocimus ruber). The latter species received fatty minced meat as part of their diet, which was also accessible to the flamingos. Weakness and poor body condition of one flamingo were noted. On clinical examination, the animal was emaciated, hypoglycemic, and showed a severe impaction of the bill with a mixture of lard, mud, and sand. This mixture had compressed the tongue and eventually had most likely prevented further food intake. In five additional flamingos, a bulging of the gular area, similar to the extension of this area during the tongue-retraction stage of the feeding cycle, was noted and interpreted as a sign of tongue displacement by similar masses in their bills. All animals were caught and the masses removed. All animals resumed food intake immediately, and the emaciated animal rapidly improved in condition. Food presentation was changed so that the trays for the other species were no longer accessible to the flamingos, and no similar problems have been observed since that time.  相似文献   
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