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排序方式: 共有177条查询结果,搜索用时 15 毫秒
21.
Silva MA Peixoto GC Sousa PC Bezerra FS Bezerra AC Silva AR 《Reproduction in domestic animals》2012,47(1):e4-e6
This study verifies the interactions between straw size and thawing rates and their impact on the epididymal sperm from this species. Caudae epididymidum from 10 agoutis were subjected to retrograde washing using a coconut water extender (ACP‐109c®). Epididymal sperm were evaluated and extended in ACP‐109c® plus egg yolk (20%) and glycerol (6%). The samples were packaged in 0.25‐ or 0.50‐ml straws, frozen in liquid nitrogen and thawed at 37°C/1 min or 70°C/8 s, followed by a re‐evaluation. The use of 0.25‐ml straws thawed at 37°C/1 min provided a value of 26.6% for sperm motility. No interactions between straw size and thawing rates were verified on agouti sperm (p > 0.05), but when 0.5‐ml straws were thawed at 70°C/8 s, sperm vigour decreased significantly (p < 0.05). It is recommended that the agouti epididymal sperm cryopreserved in ACP‐109c® extender should be packaged in 0.25‐ or 0.50‐ml straws and thawed at 37°C/60 s. 相似文献
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23.
Richtzenhain LJ Cortez A Heinemann MB Soares RM Sakamoto SM Vasconcellos SA Higa ZM Scarcelli E Genovez ME 《Veterinary microbiology》2002,87(2):139-147
Bovine brucellosis and leptospirosis are important causes of bovine abortion around the world. Both diseases can be serologically diagnosed, but many factors may cause false positive and negative results. Direct methods based on bacteriological isolation are usually employed, but they are difficult, time consuming and dangerous. Monoplex polymerase chain reaction (PCR) have been successfully described for the detection of Brucella spp. and Leptospira spp. Aiming at improvement in the direct diagnosis, a multiplex PCR (mPCR) for the detection of these agents in aborted bovine fetuses is described. The detection threshold of the mPCR was evaluated in experimentally contaminated bovine clinical samples using a conventional proteinase K/SDS or a boiling-based extraction protocols. The mPCR was applied to two groups of clinical samples: 63 episodes of bovine abortion and eight hamsters experimentally infected with Leptospira interrogans serovar pomona. Adopting microbiological isolation as reference, the test showed a sensitivity of 100% in both groups of clinical samples. Seven samples collected from bovine fetuses were Brucella spp. culture negative but showed positive results in mPCR. Regarding Leptospira spp. detection, similar results were observed in three bovine clinical samples. All hamsters infected with Leptospira were positive in both microbiological culture and mPCR. The boiling extraction protocol showed better results in some clinical samples, probably by the removal of PCR inhibitors by heat treatment. The high sensitivity, simplicity and the possibility of detection of both bacteria in a single tube reaction support the use of the mPCR described in the routine diagnosis. 相似文献
24.
Andrea Gudan Branka Artukovi? Zeljko Cvetni? Silvio Spici? Ana Beck Marko Hohsteter Tomo Nagli? Ingeborg Bata Zeljko Grabarevi? 《Journal of zoo and wildlife medicine》2008,39(3):386-391
Tuberculosis due to Mycobacterium africanum was diagnosed in an adult female hyrax (Procavia capensis). Pathologic examination revealed disseminated tuberculous lesions. The same pathologic changes were also found in a male hyrax that died a year later. Both animals were imported from the United Arab Emirates and were held in captivity at the Zagreb Zoo in Croatia. The source of infection remains unknown. The acid-fast bacteria isolated from the lungs of the female hyrax were identifyed by polymerase chain reaction as Mycobacterium tuberculosis complex and Geno Type MTBC test confirmed the strain to be M. africanum I. 相似文献
25.
Spontaneous and experimental poisoning with the swainsonine-containing and calystegine-containing plant Ipomoea carnea subsp fistulosa is described. Three of 8 goats presenting with emaciation, weakness, symmetrical ataxia, posterior paresis, proprioceptive deficits, abnormal posture, abnormal postural reaction, and muscle hypertonia were necropsied. I fistulosa was suspected to be the cause of the neurologic disease in all cases. An experiment was conducted to confirm the diagnosis using 12 goats and diets containing 3 different concentrations of the plant. All goats fed I fistulosa developed neurological signs that were similar to those observed in the spontaneous intoxication. Muscle atrophy and pallor were the only macroscopic changes observed in spontaneous and in experimental intoxication. Histological lesions of spontaneous and experimental animals were similar. The most prominent lesion was cytoplasmic vacuolation in neurons of the central and the autonomous nervous system, pancreatic acinar cells, hepatocytes, Kupffer cells, follicular epithelial cells of the thyroid gland, and macrophages of the lymphatic tissues. Neuronal necrosis, axonal spheroids formation, and astrogliosis were additionally observed in the brain. Ultrastructurally, the cytoplasmic vacuoles consisted of distended lysosomes surrounded by a single-layered membrane. Nonreduced end-rests or sequence of alpha-Man, alpha-Glc, beta(1-4)-GlcNAc, and NeuNAc on lysosomal membrane were revealed by lectin histochemistry. Samples of plants used in the experimental trial contained swainsonine and calystegine and their intermediary derivate. We conclude that I fistulosa induces a glycoprotein storage disease primarily based on the inhibition of the lysosomal alpha-mannosidase by the alkaloid swainsonine. 相似文献
26.
The effects of total ammonia (TAN; NH4++ NH3) on the reproductive performance, survival, growth and moulting of wild Penaeus paulensis (Pérez-Farfante) broodstock were studied to determine optimal rearing conditions. Based on previously established ‘safe levels’ for P. paulensis adults (3.4 and 4.2 mg L?1 TAN), two 46-day trials were performed. In the first trial, six females and four males were stocked in 700-L tanks under three treatments (0.37, 2.53 and 6.86 mg L?1 TAN) with at least two replicates per treatment. In trial 2, ammonia levels of 0.68, 1.55 and 2.62 mg L?1 TAN were assigned to three 6000-L tanks, each stocked with 36 females and 24 males. Ammonia only influenced the survival of females and the growth of males exposed to 6.86 mg L?1 TAN (0.21 mg L?1 NH3). No further effects of ammonia on moulting and reproductive performance were detected. The present results demonstrate that up to 2.62 mg L?1 TAN, coupled with 0.07 mg L?1 NH3 and 1.50 mg L?1 NO2, will not impair reproductive performance of P. paulensis. It is suggested that water quality for the maturation of P. paulensis may be maintained through lower daily water exchange rates instead of the usual high levels (150-300%) employed on penaeid shrimp maturation systems. 相似文献
27.
Replacement of fishmeal by two types of fish protein hydrolysate in feed for postlarval shrimp Litopenaeus vannamei
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B.P.T. Quinto J.V. Albuquerque R.S. Bezerra S. Peixoto R. Soares 《Aquaculture Nutrition》2018,24(2):768-776
After filleting of tilapia, the material remaining is discarded and this waste represents about 700 g/kg of fish body volume, corresponding to carcass and viscera. These leftovers are important sources of proteins that can be used as feed in aquaculture industry by producing protein hydrolysates. In this study, two protein hydrolysates of tilapia were produced, with one (FPH1) and two (FPH2) hours of hydrolysis. The nutritional composition of the hydrolysates showed desirable levels of crude protein and essential amino acids. Electrophoresis revealed peptides ranging from 10 to 250 kDa. In addition, caseinolytic activity was recorded by zymogram. The hydrolysates were incorporated separately in experimental diets to replace fishmeal at distinct levels: 0, 40, 80 and 120 g/kg, totalizing seven diets named 0 (control), 40H1, 80H1, 120H1, 40H2, 80H2 and 120H2. A 45‐day feeding trial was carried out to evaluate the zootechnical performance of postlarvae fed these diets. In conclusion, the use of FPH2 as a substitute for fishmeal promotes better shrimp growth than FPH1 and allows higher levels of substitution. In addition, it is recommended a 60 g/kg fishmeal replacement by FPH2 to improve growth. 相似文献
28.
Cross‐effects of dietary probiotic supplementation and rearing temperature on growth performance,digestive enzyme activities,cumulative mortality and innate immune response in seabass (Dicentrarchus labrax)
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L.F. Pereira M.J. Peixoto P. Carvalho K. Sansuwan G.A. Santos J.F.M. Gonçalves R.O.A. Ozório 《Aquaculture Nutrition》2018,24(1):453-460
Probiotic influence on fish immune response and digestive capacity is extensively discussed in aquaculture. In this experiment, a feeding trial was carried out for 100 days to evaluate the cross‐effects of probiotic supplementation and rearing temperature (17, 20 and 23°C) in juvenile seabass (Dicentrarchus labrax). The experimental diet was supplemented with a commercial probiotic blend (Biomin AquaStar Growout) at 3 g/kg diet (5.23 × 108 CFU/kg diet), and tested against a non‐supplemented diet (control). Growth performance and innate immune responses were analysed at 70 and 100 days of feeding, whereas digestive enzyme activities were determined at 100 days of feeding. At the end of the feeding trial, fish were subjected to a handling stress and cumulative mortality was recorded. Digestive enzyme activities were influenced by temperature, with α‐amylase and lipase activities peaking at the higher temperature (23°C) and trypsin at the lower temperature (17°C). Immune parameters showed a significant temperature versus feeding duration effect, with complement system (ACH50) and peroxidase peaking at 70 and 100 days of feeding, respectively. Poststress cumulative mortality was higher at the lowest temperature (17°C), especially in fish fed the control diet. In conclusion, water temperature was the main variable affecting the studied parameters, whereas the dietary probiotic supplementation had influence on the chymotrypsin activity and survival rate in seabass reared at 17°C. 相似文献
29.
Palytoxin (PLTX), one the most potent marine toxins, and/or its analogs, have been identified in different marine organisms, such as Palythoa soft corals, Ostreopsis dinoflagellates, and Trichodesmium cyanobacteria. Although the main concern for human health is PLTXs entrance in the human food chain, there is growing evidence of adverse effects associated with inhalational, cutaneous, and/or ocular exposure to aquarium soft corals contaminated by PLTXs or aquaria waters. Indeed, the number of case reports describing human poisonings after handling these cnidarians is continuously increasing. In general, the signs and symptoms involve mainly the respiratory (rhinorrhea and coughing), skeletomuscular (myalgia, weakness, spasms), cardiovascular (electrocardiogram alterations), gastrointestinal (nausea), and nervous (paresthesia, ataxia, tremors) systems or apparates. The widespread phenomenon, the entity of the signs and symptoms of poisoning and the lack of control in the trade of corals as aquaria decorative elements led to consider these poisonings an emerging sanitary problem. This review summarizes literature data on human poisonings due to, or ascribed to, PLTX-containing soft corals, focusing on the different PLTX congeners identified in these organisms and their toxic potential. 相似文献
30.
V. Galhano F. Peixoto J. Gomes-Laranjo E. Fernández-Valiente 《Water, air, and soil pollution》2009,197(1-4):211-222
The effects of bentazon and molinate, two selective herbicides recommended for integrated weed management in rice, were studied in Anabaena cylindrica, an abundant cyanobacterium isolated from a Portuguese rice field agro-ecosystem. Comparative effects of both herbicides on A. cylindrica were estimated under laboratory conditions by measuring its dry weight yield, photopigments, and carbohydrate and protein contents in a time- and dose-dependent exposure throughout 72 h. Photosynthesis and respiration were also monitored. The results revealed that both herbicides exerted a pleiotropic effect on the cyanobacterium at the range of concentrations tested (0.75–2 mM). Growth, chlorophyll a, carotenoids and phycobiliproteins were more adversely affected by molinate than by bentazon. Cyanobacterial growth inhibitions of over 50% were observed after 48 h when 1.5–2 mM of molinate were applied. Bentazon concentrations ranging from 0.75 to 2 mM did not significantly modified chlorophyll a content with time, however, considerable reductions in chlorophyll a, carotenoids and specially phycobiliproteins were observed with molinate. Protein content increased with both herbicides although the effect was particularly noticeable with the highest concentration of molinate. Herbicide effects on carbohydrate content were contrasting: molinate increased this organic fraction whereas bentazon decrease it. Photosynthesis and respiration were inhibited by both herbicides and higher molinate concentrations (1.5–2 mM) completely ceased O2 evolution after 48 h. Since A. cylindrica is abundant in Portuguese rice fields and could be used as an inoculum source in rice biofertilization programs, their protection from potential residual effects of herbicides is fundamental for a correct management of local soil fertility. 相似文献