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61.
Claudia Rengifo-Herrera Luis Miguel Ortega-Mora Mercedes Gómez-Bautista Francisco Javier García-Peña Daniel García-Párraga Susana Pedraza-Díaz 《Veterinary parasitology》2013,191(1-2):112-118
A study was conducted to investigate the presence of Cryptosporidium and Giardia in Antarctic marine mammals. A total of 270 faecal samples from different species of pinnipeds from different locations in the South Shetland Islands and Antarctic Peninsula were analysed by immunofluorescence microscopy and PCR. Cryptosporidium was detected by PCR in three samples from Southern elephant seals (Mirounga leonina) and 2 Weddell seals (Leptonychotes weddellii). However, no oocysts were observed in any of the samples by immunofluorescence microscopy. Molecular characterisation of the isolates, using the 18S rDNA, the HSP70 and the COWP loci, revealed the presence of a Cryptosporidium sp., previously reported from an Antarctic Southern elephant seal, in the elephant seals and a novel genotype in Weddell seals. Giardia could not be detected in any of the samples analysed. 相似文献
62.
Wendy Mercedes Rauw 《畜牧与生物技术杂志(英文版)》2013,4(1):33
Background
Play behavior has been proposed as a new potential indicator of animal welfare. Animals play only if they are in a relaxed state. Play may improve adaptability to challenging environments which may be of interest in the breeding objective. Little information is available on play behavior in livestock species. The aim of the present study is to investigate whether play behavior in post-weaned piglets can be induced instantly in the presence of additional space and whether play markers are body weight, sex, and litter dependent. It is investigated whether playfulness is elicited by the moment or if this measure is consistent over different days.Methods
Thirty two piglets from four litters were released into a corridor and video recorded for eight min at 37, 41, 44 and 48 d of age. The first test was considered as an adjustment period and was not included in the analysis. In the second to the fourth test, joyful brusque movements (jumping, turning and running) were recorded with a camera and total number of movements (JOY#) and total time (JOYtime) were estimated individually. Animals were weighed at 41 d of age.Results
Females had higher scores of JOY# and JOYtime than males but this was significant only for JOY# at 41 d of age (P < 0.05). The effect of age was highly significant both for JOY# and JOYtime (P < 0.01). Animals with a higher JOY# and JOYtime also expressed a higher JOY# and JOYtime in the other tests, but this was significant only between 44 and 48 d of age (P < 0.01). Body weight at 41 d of age was not significantly related to JOY# and JOYtime in any of the tests.Conclusions
Locomotor play was induced instantly by the provision of increased space allowance. Litter origin had a significant effect on play behavior. In addition, locomotor play scores were consistent between two of the three tests. 相似文献63.
Marina Solé Maria D. Gómez Alfonso Martínez Galisteo Rute Santos Mercedes Valera 《Journal of Equine Veterinary Science》2013
This paper describes the handled walking and trotting kinematics (linear, temporal, and angular traits) of 35 Menorca Purebred (MEN) stallions, and the relationships among these variables is presented for the first time, along with a discussion of the influence of the hind limb pastern angle on kinematic variables at both gaits. For data collection, all animals, aged between 3 and 10 years old and belonging to 28 different studs, were recorded under the same experimental and environmental conditions, using a three-dimensional (3D) semiautomatic movement analysis system. A total of 24 kinematic variables (temporal, linear, and angular) at the walk and the trot and a morphometric variable measured at the mid stance position of walking (hind pastern angle) were included in this analysis. Angle-time diagrams of the hind pastern angle while walking and trotting normalized to stride duration were also obtained. Generally the MEN stallions' forelimb movements closely resembled the movement characteristics of other European dressage performance breeds, while the hind limb locomotion showed a greater likeness to Iberian dressage Purebreds. Despite this, their ability in collection and propulsion at the walk and the trot was relatively low. The hind limb pastern conformation was partially connected to the hind limb movements for both gaits, with an apparently negative effect of excessively upright pasterns on the amplitude at the trot, which indirectly reduced collection ability. 相似文献
64.
65.
Stefanie Anne van Bergeijk José Antonio Paullada Salmerón Ana Isabel López Pérez José Moreno José Pedro Cañavate Mercedes García‐González 《Aquaculture Research》2013,44(11):1724-1730
Rotifers, used in aquaculture as feed for early larval stages, are poor in carotenoids compared with copepods, the natural most common prey item of marine fish larvae. A minimal sufficient level of carotenoids in fish larvae may be essential for a correct development. The freshwater microalga Muriellopsis sp. has been identified as a potential source of the carotenoid lutein with possible application in aquaculture. Lutein is a potent antioxidant, with potentially beneficial effects as a carotenoid for fish larvae. This study describes the lutein enrichment of the rotifer Brachionus sp. when incubated with homogeneously dispersed suspensions of freeze‐dried, lutein‐rich Muriellopsis sp. in seawater. A short enrichment time (2 or 2.5 h) resulted in a higher lutein content of the rotifers than a long enrichment time (13.5 or 24 h). Although the concentration of lutein in enriched rotifers, 0.06–0.16 mg (g dry weight)?1 was low compared with its content in Muriellopsis sp. [about 3 mg (g dry weight)?1], it was in the range reported for natural copepod populations. Therefore, we conclude that freeze‐dried biomass of Muriellopsis sp. can be used to enrich rotifers with lutein, providing an adequate level of this carotenoid for marine fish larvae. 相似文献
66.
Marko Lovrić Mercedes Rois-Díaz Michael den Herder Andrea Pisanelli Nataša Lovrić Paul J. Burgess 《Agroforestry Systems》2018,92(4):863-876
The factors that determine the implementation of four alternative agroforestry practices or no agroforestry on a theoretical 200 ha farm in Mediterranean Europe were examined using an analytic network process (ANP) model. The four agroforestry practices considered were implementation of a form of (i) high natural and cultural value agroforestry, (ii) agroforestry with high value trees, and agroforestry for (iii) arable and (iv) livestock systems. The ANP model was developed in a participatory manner through a systematic series of quantitative questionnaires and workshops with agroforestry researchers. In general, all the Mediterranean agroforestry systems were associated with high benefits and opportunities, but also with high costs and high risks. The greatest benefits were attributed to high natural and cultural value agroforestry systems, which greatly contributed to the highest priority of this system. Overall ranking of priorities for the agroforestry management alternatives show robustness in the sensitivity analysis. The “no agroforestry” land use became the preferred option when costs were given a weighting of 0.50 or greater. 相似文献
67.
Yessotoxin (YTX) is a polyether compound produced by dinoflagellates and accumulated in filter feeding shellfish. No records about human intoxications induced by this compound have been published, however it is considered a toxin. Modifications in second messenger levels, protein levels, immune cells, cytoskeleton or activation of different cellular death types have been published as consequence of YTX exposure. This review summarizes the main intracellular pathways modulated by YTX and their pharmacological and therapeutic implications. 相似文献
68.
Delgado-Rodríguez M Ruiz-Montoya M Giraldez I López R Madejón E Díaz MJ 《Journal of agricultural and food chemistry》2011,59(24):13035-13042
The influence of control parameters (aeration, moisture, and C/N ratio) during composting of a municipal solid waste (MSW)-legume-trimming residue (LTR) mixture was studied at a pilot plant scale. Factors measured included the composition of the main volatile organic carbons (VOCs) emitted including limonene, β-pinene, 2-butanone, undecane, phenol, toluene, and dimethyl disulfide. Polynomial models were found to reproduce the experimental results with errors at less than 10%. The relative influence of the independent variables on temperature and selected VOCs followed the order: aeration > moisture > C/N. A high aeration rate results in higher (strong negative effect) values on selected VOCs emissions (41-71% on emitted VOCs variation). Moisture had a positive and negative effect depending on the selected VOCs. A high C/N ratio caused lower production of VOCs except for undecane and 2-butanone. Providing an aerobic environment (0.05 Lair kg(-1) min(-1)), high C/N ratios (>50), and medium moisture (55%) minimize emitted VOCs during MSW composting, ultimately resulting in less odors in the surrounding environment. 相似文献
69.
Michele Silveira Coelho Bruna da Silva Menezes Silvia Leticia Rivero Meza Bruno Lainetti Gianasi Myriam de las Mercedes Salas-Mellado Margareth Copertino 《Journal Of Aquatic Food Product Technology》2013,22(7):1096-1106
ABSTRACTThis study was conducted to evaluate the biochemical and nutritional characteristics of naturally occurring estuarine macroalgae in the Patos Lagoon (Rio Grande, Brazil). The study of these macroalgae, dominated by Ulva and Cladophora species, contributes to current research on the potential utilization of green tide-forming algae. Although high levels of carotenoids (378 ± 0.02 µg g?1) and antioxidant activity (75.0% for DPPH) were found in the naturally occurring macroalgae, these macroalgae cannot be used in the food industry due to the presence of toxic levels of arsenic (exceeding the thresholds of both French and Brazilian legislation for food). Regarding the potential of the studied macroalgae as a biofuel source, the low lipid and very high carbohydrate contents suggest a possible use in the fermentation of ethanol, butanol, or methane. 相似文献
70.
García-Sancho M Rodríguez-Franco F Sainz A Rodríguez A Silván G Illera JC 《The Canadian veterinary journal. La revue veterinaire canadienne》2005,46(7):630-634
This study evaluates serum gastrin concentrations in dogs with chronic lymphocytic-plasmacytic enteritis, as well as its possible relationship with the severity of lesions present in the stomach. To achieve this aim, 5 dogs without gastrointestinal disease and 15 dogs with chronic lymphocytic-plasmacytic enteritis were included. Serum gastrin concentrations were significantly increased in dogs with chronic lymphocytic-plasmacytic enteritis compared with those in dogs without gastrointestinal disease. Also, there was a positive correlation between the severity of the gastric lesion and the serum gastrin concentration. Our findings indicate the possibility that gastrin plays a role in the etiology of an accompanying chronic antral gastritis in canine chronic lymphocytic-plasmacytic enteritis. 相似文献