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921.
Female reproductive system morphology of crab‐eating fox (Cerdocyon thous) and cryopreservation of genetic material for animal germplasm bank enrichment
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L. C. Machado K. C. S. Roballo F. S. Cury C. E. Ambrósio 《Anatomia, histologia, embryologia》2017,46(6):539-546
The sprawl of the urbanization and road network process without building ecological corridors contributes to the high mortality rates and a threat to the population decline of wild species such as the crab‐eating fox. A strategy for the ex situ conservation is the study of the reproductive biology of the species and cryopreservation of their genetic heritage through the formation of an animal germplasm bank. This research is in accordance with the principles adopted by Brazilian College of Animal Experimentation. Reproductive systems of Cerdocyon thous females (n = 7) were examined macroscopically and microscopically by histological techniques and scanning electron microscopy. Gross features showed the shape of the ovaries was similar to a bean, and the elongated oviducts lengths were between 5 and 8 cm, with body of the uterus (3 cm) with long and narrow uterine horns (9–11 cm). The cervix was as a single annular conformation carrying out communication between the uterus and the vagina. The vagina has lengthened and circular muscle and the vulva with dense anatomical conformation with a quite pronounced clitoris. In addition, with regard to the establishment of a cell line (fibroblasts) for the gene bank enrichment, cells showed a low clonogenic capacity, especially when compared to domestic dogs, which can be explained by “in vitro” environment, age and diet of the animal. However, it was possible to create a bank of limited cell number. This study had morphological and preservationist character and aimed to help at long term in the conservation of wild animal's genetic resources. 相似文献
922.
Undernutrition in the parental and first generation provokes an organ‐specific response to oxidative stress on neonates of second filial generation of Wistar rats
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![点击此处可从《Journal of animal physiology and animal nutrition》网站下载免费的PDF全文](/ch/ext_images/free.gif)
R. Baños‐Gómez N. S. Cruz‐Cansino T. Suarez‐Diéguez C. Valadez‐Vega E. Ramírez‐Moreno E. Alanís‐García J. A. Ariza‐Ortega J. J. Manríquez‐Torres E. Zamora‐Romo L. Delgado‐Olivares 《Journal of animal physiology and animal nutrition》2017,101(2):267-274
Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second‐generation neonates (F2) of undernourished rats. For this purpose, both parents in parental (F0) and first generation (F1) were fed with a low‐nutrient diet. Body mass and length decreased (p < 0.05) in F0, F1 and F2 being the F1 males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F2 neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ‐specific response, on F2 neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions. 相似文献
923.
924.
Effects of increasing amount of dietary Prosopis laevigata pods on performance,meat quality and fatty acid profile in growing lambs
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L. O. Negrete J. M. Pinos‐Rodríguez A. Grajales‐Lagunes J. A. Morales J. C. García‐López H. A. Lee‐Rangel 《Journal of animal physiology and animal nutrition》2017,101(5):e303-e311
A study with finishing lambs assessed the effect of dietary inclusion of Prosopis laevigata pods (PLPs) on performance, carcass characteristics, meat traits and fatty acid profile of subcutaneous fat. Twenty‐one Rambouillet lambs (27.0 ± 3.0 kg BW) were assigned to one of three experimental diets with 0, 150 and 300 g PLP/kg DM. Evaluation of growth performance lasted 49 days. The experimental design was completely randomized and analysed with a mixed model. Lambs fed diets with 0, 150 and 300 g PLP had similar growth performance. Lambs fed diets with 300 g PLP/kg DM had better (p < 0.05) carcass yield and classification, less (p < 0.05) fat deposition and lower lightness (L*) value (p < 0.05) in meat than lambs fed diets with 0 and 150 g PLP/kg DM. Saturated fatty acids (palmitic and stearic) decreased (p < 0.05) and unsaturated fatty acids (oleic and linoleic) increased (p < 0.05) in subcutaneous fat of lambs fed diets with 150 and 300 g pods as compared with lambs not fed PLP. Prosopis laevigata pods are a safe feedstuff that can replace a third of conventional ingredients and reduce feed costs in growing lambs. Addition of PLP reduced (p < 0.05) total feed cost by 21%. 相似文献
925.
Direct and maternal additive effects are not the main determinants of Iberian piglet perinatal mortality
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M. Muñoz M.C. Rodríguez L.A. García‐Cortes A. González J.M. García‐Casco L. Silió 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(6):512-519
Data of 127,800 Iberian piglets were used to study genetic parameters of mortality at birth at the piglet level. These records proceed from three data sets: 4,987 litter of 2,156 sows of a dam line, 2,768 litter of 817 sows of a complete diallel cross between four Iberian strains and 7,153 litter of 2,113 sows of the Torbiscal composite line. Perinatal mortality was considered as a binary trait, and Bayesian threshold animal models were fitted to separately analyse the three data sets. The posterior means of direct heritability were 0.010, 0.004 and 0.003, and those of maternal heritability were 0.034, 0.011 and 0.014 for dam line, diallel cross and Torbiscal line, respectively. Important effects of litter size and parity order were inferred in the three data sets, of within‐breed cross‐breeding parameters in the diallel cross and of sex and sow handling in the Torbiscal line Therefore, the inclusion of perinatal mortality in the objective of selection is questionable in this breed and strategies for reducing piglet mortality successful in other breeds should be considered. 相似文献
926.
Genetic diversity of the Mexican Lidia bovine breed and its divergence from the Spanish population
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P.G. Eusebi O. Cortés S. Dunner J. Cañón 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(4):332-339
Lidia bovine breed exists since the XIV century in the Iberian Peninsula. These animals were initially produced for meat but some, showing an aggressive behaviour which difficulted their management, were used to participate in popular traditional and social events. A specialization of the breed giving rise to the original Lidia population is documented in Spain since mid-XVIII century. Following the same tradition than in the Spanish population, Mexico used aggressive animals at the beginning of the XX century until two families of breeders started importing Lidia breed bovines from Spain with the aim of specializing their production. Each family (Llaguno and González) followed different breeding managements, and currently, most of the Lidia Mexican population derives from the Llaguno line. Although genetic structure and diversity of the Spanish population have been studied (using autosomal microsatellite markers, Y chromosome DNA markers and mitochondrial DNA sequences), the Mexican population is not analysed. The aim of the study was to assess both the genetic structure and diversity of the Mexican Lidia breed and its relationship with the original Spanish population using the same molecular tools. A total of 306 animals belonging to 20 breeders issued from both existing Mexican families were genotyped, and the genetic information was compared to the previously existing Spanish information. Slightly higher levels of genetic diversity in Mexican population were found when comparing to the Spanish population, and the variability among populations accounted for differences within them showing mean values of 0.18 and 0.12, respectively. Animals from the Mexican breeders, belonging to each of the two families, clustered together, and there was little evidence of admixture with the Spanish population. The analysis of Y chromosome diversity showed a high frequency of the H6 haplotype in the Mexican population, whereas this haplotype is rare in the Spanish, which is only found in the Miura (100%) and Casta Navarra (38%) lineages. Mitochondrial DNA revealed similar haplotypic pattern in both Spanish and Mexican populations, which is in accordance with most of the Mediterranean bovine breeds. In conclusion, as the Mexican Lidia population had initially a small number of founders and its current population has been reared isolated from their Spanish ancestors since a long time, these bottleneck effects and a combination of mixed cattle origin are the factors that might erase any trace of the Spanish origin of this population. 相似文献
927.
Prevention of intestinal parasites in a tri‐border area of Latin America: Children perceptions and an integral health education strategy
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M. R. Rivero M. M. Salas R. Valente M. J. Nores C. De Angelo J. Arrabal S. Costa O. D. Salomón 《Zoonoses and public health》2017,64(8):673-683
To investigate knowledge of school‐aged children and their perception on intestinal parasites, and to assess knowledge reconstruction on prevention practices after specific training in the subject. We performed an activity package that included the analysis of children's drawings of intestinal parasites, and information and communication technologies (ITCs) to transfer knowledge about these pathogens and prevention measures. Retrieval learning activities were performed to fixation of general and specific prevention and control measures.Overall, we found that there is a knowledge gap in many aspects of parasite biology and ecology, and therefore on the risk of infection and acquisition mechanisms. After ITCs, the children improved their knowledge over non‐trained children.The approaches used to transfer knowledge and for learning, fixation were valuable tools for incorporating changes in misconceptions and in the deep‐rooted habits that favour entero‐parasitic diseases. This has important implications for the specific design of future education materials and campaigns. Understanding of perceptions helps to provide justifications and knowledge to achieve changes in unhealthy habits, and it constitutes the basis for the transformation of many risky practices. 相似文献
928.
María Celina Luján-Hidalgo Deisy Ermeth Gómez-Hernández Juan José Villalobos-Maldonado Miguel Abud-Archila Joaquín Adolfo Montes-Molina Samuel Enciso-Saenz 《Compost science & utilization》2017,25(2):95-101
The aim of this investigation was to determine the effect of vermicompost, vermiwash, and phosphate rock on plant, total phenols, flavonoids, and anti-oxidant activity in Piper auritum Kunth leaves. P. auritum plants were obtained from cuttings and were planted according to the Box-Behnken experimental design with three repetitions at the central point. The factors and levels were vermicompost (10, 20, and 30 g plant?1), vermiwash (5, 10, and 15 mL plant?1), and phosphate rock (1, 2, and 3 g plant?1). Plant growth parameters (plant height, stem diameter, leaves number) and chlorophyll content were measured 1 month after treatment applications. Total phenols, total flavonoids, and 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity was measured after 4 months. Vermicompost, vermiwash, and phosphate rock had no statistically significant effect on plant growth. Plant height, stem diameter, leaves number, chlorophyll, innermost number, fresh weight stem, fresh weight leaves, fresh weight root, dry weight stem, dry weight leaves, and dry weight root were not different among treatments. Total phenolic compounds were statistically affected for both vermiwash and phosphoric rock (p < 0.05) and the anti-oxidant activity decreased by vermicompost addition. The application of 15 mL plant?1 vermiwash, 1 g phosphate rock, and 20 g vermicompost plant?1 increased the total phenol content. 相似文献
929.
Winfried Schröder Stefan Nickel Simon Schönrock Roman Schmalfuß Werner Wosniok Michaela Meyer Harry Harmens Marina V. Frontasyeva Renate Alber Julia Aleksiayenak Lambe Barandovski Oleg Blum Alejo Carballeira Maria Dam Helena Danielsson Ludwig De Temmermann Anatoly M. Dunaev Barbara Godzik Katrin Hoydal Zvonka Jeran Gunilla Pihl Karlsson Pranvera Lazo Sebastien Leblond Jussi Lindroos Siiri Liiv Sigurður H. Magnússon Blanka Mankovska Encarnación Núñez-Olivera Juha Piispanen Jarmo Poikolainen Ion V. Popescu Flora Qarri Jesus Miguel Santamaria Mitja Skudnik Zdravko Špirić Trajce Stafilov Eiliv Steinnes Claudia Stihi Ivan Suchara Lotti Thöni Hilde Thelle Uggerud Harald G. Zechmeister 《Annals of Forest Science》2017,74(2):31
Key message
Moss surveys provide spatially dense data on environmental concentrations of heavy metals and nitrogen which, together with other biomonitoring and modelling data, can be used for indicating deposition to terrestrial ecosystems and related effects across time and areas of different spatial extension.Context
For enhancing the spatial resolution of measuring and mapping atmospheric deposition by technical devices and by modelling, moss is used complementarily as bio-monitor.Aims
This paper investigated whether nitrogen and heavy metal concentrations derived by biomonitoring of atmospheric deposition are statistically meaningful in terms of compliance with minimum sample size across several spatial levels (objective 1), whether this is also true in terms of geostatistical criteria such as spatial auto-correlation and, by this, estimated values for unsampled locations (objective 2) and whether moss indicates atmospheric deposition in a similar way as modelled deposition, tree foliage and natural surface soil at the European and country level, and whether they indicate site-specific variance due to canopy drip (objective 3).Methods
Data from modelling and biomonitoring atmospheric deposition were statistically analysed by means of minimum sample size calculation, by geostatistics as well as by bivariate correlation analyses and by multivariate correlation analyses using the Classification and Regression Tree approach and the Random Forests method.Results
It was found that the compliance of measurements with the minimum sample size varies by spatial scale and element measured. For unsampled locations, estimation could be derived. Statistically significant correlations between concentrations of heavy metals and nitrogen in moss and modelled atmospheric deposition, and concentrations in leaves, needles and soil were found. Significant influence of canopy drip on nitrogen concentration in moss was proven.Conclusion
Moss surveys should complement modelled atmospheric deposition data as well as other biomonitoring approaches and offer a great potential for various terrestrial monitoring programmes dealing with exposure and effects.930.