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101.
Elena Palacios Ilie S. Racolta Acuacultores de la Paz 《Journal of the World Aquaculture Society》1999,30(2):180-191
Second generation Penaeus vannamei broodstack, pond-reared and wild populations, were compared for spawning frequency and several variables associated with reproductive performance. For this purpose, 470 pond-reared and 237 wild-caught individually tagged females were stocked with males of the same origin in ten maturation tanks in a commercial hatchery, and several productivity variables were recorded over time. Results of the analysis indicate that wild shrimp had higher mating and spawning frequencies compared to pond-reared broodstock. The number of nauplii per spawn was higher for wild shrimp, but fertilization and hatching rates were higher for pond-reared spawners. A larger proportion of nonmating females were found in pond-reared shrimp; whereas, wild females had a higher potential for multiple matings. The spawn quality (fertilization and hatching rates, percentage of viable spawns, and number of nauplii) in consecutive matings did not decline substantially. The present study indicates that selection of females with multiple spawning capabilities can be an important commercial strategy to improve nauplii production over the short term. Pond-reared broodstock can be an adequate source for applying this strategy because of their year-round availability and an overall acceptable reproductive performance. 相似文献
102.
Ornelas-Paz Jde J Yahia EM Gardea-Bejar A 《Journal of agricultural and food chemistry》2007,55(16):6628-6635
A liquid chromatography-mass spectrometry (LC-MS) method was developed to simultaneously identify and quantify carotenoids and tocopherols in the fruit of seven mango cultivars grown in Mexico. Fruit maturity was characterized objectively, and carotenoids and tocopherols were isolated by solvent extraction and analyzed by HPLC coupled to a C30 stationary phase and diode array, fluorescence, and mass (time-of-flight) detectors. All cultivars had a similar carotenoid pattern, in which all-trans-beta-carotene and dibutyrates of all-trans-violaxanthin and 9-cis-violaxanthin were the most abundant. The content of all-trans-beta-carotene ranged between 0.4 and 2.8 mg/100 g, and 'Haden' and 'Ataulfo' mangoes had the highest amount. The amounts of all-trans-violaxanthin and 9-cis-violaxanthin (as dibutyrates) ranged between 0.5 and 2.8 mg/100g and between 0.4 and 2.0 mg/100 g, respectively. The content of alpha-tocopherol was low (200-500 microg/100 g). The results of this study indicate that all-trans-beta-carotene, all-trans-violaxanthin, and 9-cis-violaxanthin are the most abundant carotenoids in mango grown in Mexico. 相似文献
103.
M Mata‐Campuzano M Álvarez‐Rodríguez M Álvarez L Anel P de Paz JJ Garde F Martínez‐Pastor 《Reproduction in domestic animals》2012,47(6):907-914
Thawed ram spermatozoa were incubated at 37°C in the presence of dehydroascorbic acid (DHA), TEMPOL (TPL), N‐acetyl‐cysteine (NAC) and rutin (RUT), at 0.1 and 1 mm , in order to test their effects on sperm physiology. Cryopreserved spermatozoa from four rams were thawed, pooled, washed and incubated in TALP‐Hepes with 1 mm or 0.1 mm of each antioxidant, performing a replicate with induced oxidative stress (Fe2+/ascorbate). Motility (CASA), viability and mitochondrial membrane potential (flow cytometry) were analysed at 2 and 4 h. Lipoperoxidation (MDA production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were analysed at 4 h. Antioxidants, except DHA 0.1 mm , decreased motility and kinematic parameters, but had little effect on viability or mitochondrial activity. Except 1 mm DHA, the antioxidants reduced ROS at 4 h. Moreover, NAC 1 mm , rutin and TEMPOL reduced ROS and DNA damage in the presence of oxidative stress. N‐acetyl‐cysteine, rutin 1 mm and TEMPOL reduced lipoperoxidation in the presence of oxidative stress. However, DHA did not affect lipoperoxidation. At 1 mm , DHA increased DNA damage in the absence of oxidative stress. Dehydroascorbic acid effects could arise from spermatozoa having a low capacity for reducing it to ascorbic acid, and it may be tested in the presence of other antioxidants or reducing power. Future research should focus in testing whether the inhibition of motility observed for NAC, rutin and TEMPOL is reversible. These antioxidants might be useful at lower temperatures (refrigerated storage or cryopreservation) when their protective effects could be advantageous. 相似文献
104.
Badia R Zanello G Chevaleyre C Lizardo R Meurens F Martínez P Brufau J Salmon H 《Veterinary research》2012,43(1):4
ABSTRACT: Probiotic and prebiotics, often called "immune-enhancing" feed additives, are believed to deal with pathogens, preventing the need of an immune response and reducing tissue damage. In this study, we investigated if a recently developed β-galactomannan (βGM) had a similar protective role compared to Saccharomyces cerevisiae var. Boulardii (Scb), a proven probiotic, in the context of enterotoxigenic Escherichia coli (ETEC) infection. ETEC causes inflammation, diarrhea and intestinal damage in piglets, resulting in large economic loses worldwide. We observed that Scb and βGM products inhibited in vitro adhesion of ETEC on cell surface of porcine intestinal IPI-2I cells. Our data showed that Scb and βGM decreased the mRNA ETEC-induced gene expression of pro-inflammatory cytokines TNF-α, IL-6, GM-CSF and chemokines CCL2, CCL20 and CXCL8 on intestinal IPI-2I. Furthermore, we investigated the putative immunomodulatory role of Scb and βGM on porcine monocyte-derived dendritic cells (DCs) per se and under infection conditions. We observed a slight up-regulation of mRNA for TNF-α and CCR7 receptor after co-incubation of DC with Scb and βGM. However, no differences were found in DC activation upon ETEC infection and Scb or βGM co-culture. Therefore, our results indicate that, similar to probiotic Scb, prebiotic βGM may protect intestinal epithelial cells against intestinal pathogens. Finally, although these products may modulate DC activation, their effect under ETEC challenge conditions remains to be elucidated. 相似文献
105.
106.
Rodríguez-Hernández E Mosqueda J Alvarez-Sánchez ME Neri AF Mendoza-Hernández G Camacho-Nuez M 《Veterinary parasitology》2012,186(3-4):538-541
Oestrosis is highly prevalent in Mediterranean countries. Understanding the life cycle of Oestrus ovis is crucial to design effective control measures of this myiasis, largely based on the use of macrocyclic lactones. We carried out a survey of ovine oestrosis in the island of Majorca (Spain) and found that 46.03% of animals were infested in a 13-month period. Interestingly, we found significant differences in oestrosis prevalences in winter and autumn when separating the animals by group of age (P<0.001). Pearson correlation analysis showed that prevalence in lambs younger than 4 months was significantly affected by changes in air temperature (P<0.05), but this association was not significant in adult sheep (P=0.081). Chronic infestations or unsystematic treatments may explain confusing results in adult sheep. Observing the evolution of the disease in young lambs, we determined that the hypobiotic period took place from October to February and the beginning of fly activity occurred between May and June. Interannual variations in oestrosis prevalence indicate the need of monitoring the disease to establish the appropriate timing of treatments. We hypothesize that lambs are better indicators of the seasonality of oestrosis than their older counterparts. Furthermore, we propose that observing O. ovis infestations in young lambs can be used as an efficient early warning system of fly activity, to be applied in future control programs. 相似文献
107.
Tedeschi G Taverna F Negri A Piccinini R Nonnis S Ronchi S Zecconi A 《Veterinary microbiology》2009,134(3-4):388-391
Staphylococcus aureus is the most common aetiologic agent of contagious bovine mastitis. Studies of the molecular epidemiology of S. aureus strongly suggest that some genetic subsets of strains are particularly well adapted for causing infections in cattle. This communication reports the setup of experimental protocols to identify the immunogenic proteins expressed by one of the most common field isolated strain of S. aureus responsible for sub-clinical mastitis cases. The serological proteome analysis (SERPA) approach applied consists of three main steps: two-dimensional electrophoresis-based separation of the proteins contained in field isolated S. aureus extracts enriched for surface proteins, detection of immunogenic spots using anti-serum collected from sub-clinical mastitis cases and identification of antigens by mass spectrometric-based methodologies. The study allowed to identify three immunogenic proteins: DNAase translocase FtsK, ribosomal proteins S1 and a Tell-like protein. 相似文献
108.
Spugnini EP Vincenzi B Citro G Tonini G Dotsinsky I Mudrov N Baldi A 《Veterinary journal (London, England : 1997)》2009,179(1):117-120
Squamous cell carcinomas (SCC) of the skin are commonly described in cats. Reported treatments include surgery, radiation therapy and photodynamic therapy. This preliminary study reports on the management of these lesions combining the local administration of bleomycin (plus hyaluronidase for a more uniform distribution) with permeabilizing biphasic electric pulses. Nine cats with SCC graded T(2)-T(4) were treated over a 5 year period, and each cat received two sessions of electrochemotherapy (ECT) 1 week apart. The side effects of this treatment were minimal and limited to mild erythema of the nose. Seven of the cats (77.7%) had a complete response lasting up to 3 years. ECT seems to be a safe and effective option for the treatment of feline sun-induced squamous cell carcinomas and warrants further investigation. 相似文献
109.
Alicia Nevárez Alfonso López Gary Conboy William Ireland David Sims 《Journal of veterinary diagnostic investigation》2005,17(5):486-489
Crenosoma vulpis and Eucoleus aerophilus are nematode parasites that can cause verminous pneumonia in wild carnivores. There is a paucity of information regarding the distribution of parasites in the lungs and the relationship between histopathological and parasitological diagnoses in naturally infected foxes. The objectives of this study were: first, to study the lobar and airway distribution of C. vulpis and E. aerophilus in wild red foxes and second, to investigate the relationship between fecal and histopathological diagnoses. Samples from 6 sites of the lung and fecal contents were obtained from 51 wild foxes in Prince Edward Island. By fecal examination, 78.4% of wild foxes tested positive for C. vulpis and 68.6% for E. aerophilus. In contrast, 66.6% and 49% of foxes had histopathological evidence of C. vulpis and E. aerophilus in the lungs, respectively. Anatomically, C. vulpis was observed in the small bronchi and bronchioles of all pulmonary lobes whereas E. aerophilus was restricted to the large bronchi and the caudal lobes. Affected airways exhibited severe epithelial glandular hyperplasia and bronchiolar mucous metaplasia. It was concluded that C. vulpis is widely distributed in airways of all pulmonary lobes, whereas E. aerophilus is mainly restricted to the bronchi of caudal lobes. Also, this study showed that histological examination of lung underestimates the infection with E. aerophilus. 相似文献
110.
Rogers L López A Gillis A 《The Canadian veterinary journal. La revue veterinaire canadienne》2002,43(7):547-549
A 4-year-old, male Newfoundland cross was presented for lethargy, anorexia, and dysuria. The main clinical finding was an enlarged and painful prostate gland. While the dog was hospitalized, priapism developed. Following euthanasia, microscopic examination revealed that a carcinoma involving both bladder and prostate gland had widely metastasized to the penile vasculature. 相似文献