Rat neonatal intestinal wall-free graft

An experimental study was carried out in order to evaluate the regeneration capacity of the neonatal intestinal wall in ischaemia and its repercussion over organs of the immune system such as the spleen. We isolated a reservoir of small intestine in adult Sprague-Dawley rats that, after having been everted and placed at a subcutaneous level, was grafted with a free small intestine segment of neonatal Sprague-Dawley rats and analysed 3, 15 and 30 days after grafting. Samples obtained were stained with Martin's trichromic stain and studied at the light microscopic level. A total regeneration of the crypt architecture, formed by absorptive enterocytes, was observed in the interior of the reservoirs. A quantitative immunohistochemical study with monoclonal antibodies against CD4, CD8, MHC I and MHC II was carried out in the spleen of these animals. An additional immunohistochemical study was also performed in the small intestine reservoirs and spleen of transplanted animals using nitric oxide synthase (NOS) antibodies. Three days after transplantation NOS immunoreactive cells were observed in the reservoirs with transplanted neonatal small intestine. Antigenic stimulation produced, in the spleen red pulp of transplanted animals, a significant increase (P < 0.001) in the percentage of NOS, CD8 and MHC I immunoreactive cells in relation with values observed in control animals. These morphometric changes could be related with the stimulation that nitric oxide produces in the proliferation of the cytotoxic T cells.     

The pulmonary clearance of Pasteurella haemolytica in calves infected with bovine virus diarrhea or Mycoplasma bovis.

Based on current literature which commonly associates bovine virus diarrhea virus and Mycoplasma bovis with "pneumonic pasteurellosis," an investigation was conducted into the effect of these two pathogens on the capacity of bovine lung to clear inhaled Pasteurella haemolytica. There was no significant effect (p less than 0.05) of either bovine virus diarrhea virus or M. bovis on the mean clearance rate of P. haemolytica, nor did the time interval of three, five or seven days between the first inoculation and exposure to P. haemolytica and adversely affect the lung clearance rates. However, it was found that the left lungs and a higher bacterial retention (p less than 0.05) than the right lungs.     

Application of chemometric techniques in obtaining macerates with phenolic compound content similar to that of wines from the Jerez-Shery region subjected to oxidative aging.

This paper studies and quantifies the final concentration of phenolic aldehydes and acids (determined by HPLC) in a series of sobretablas wine macerates prepared with American oak shavings subjected to an accelerated aging system developed by our research group and based on thermal processes traditionally used in cooperage. This experiment aims to considerably reduce and control the oxidative aging period of oloroso wines from the Jerez-Sherry region as occurs in the dynamic system of soleras and criaderas, with the consequent economic benefits. To standardize the process by controlling the production technique of the macerates, the results were subjected to surface response methodology as a means of optimizing the experiment. The proposed model was found to be suitable after evaluation of the factors affecting the final concentration. Of the factors studied, it was found to be essential to control the charring time and/or the interactions between temperature and charring time for 10 of the 11 phenolic compounds studied.     

Influence of water quality,local knowledge and river–floodplain connectivity on commercial wild crayfish harvesting in the Atchafalaya River Basin

Water quality and river connectivity influence fisheries, but their role is not understood in wild crayfish harvest, or how water quality and river connectivity are incorporated into crayfish harvest strategies. In Louisiana, wild harvesting practices were evaluated with field observations and interviews with individual harvesters. Field observations included trap locations, water quality, water stable isotopes (2016) and habitat components over two seasons (2015 and 2016). Traps were set in less turbid water (NTU < 69.4), in depths from 1 to 3 m or 3 to 3.6 m and in locations associated with river water inputs. Harvester interviews indicated the importance of tradition (35%‐47% respondents), depth (88% respondents) and water colour (>40% respondents; a surrogate for turbidity and connectivity) in harvesting initiation and trap locations. Harvesters appeared to follow lateral water movements onto and within the floodplain, likely based on local environmental knowledge.     

First detection of spring viraemia of carp virus in common carp (Cyprinus carpio L.) affected by a septicaemic disease in Mexico

Spring viraemia of carp (SVC) is an infectious disease responsible for severe economic losses for various cyprinid species, particularly common carp (Cyprinus carpio carpio). The causative agent is the SVC virus (SVCV), a member of the Sprivivirus genus, Rhabdoviridae family, and a List 1 pathogen notifiable by the World Organization for Animal Health. This study describes the diagnosis of an SVCV pathogen isolated in October 2015 from wild common carp inhabiting a natural lagoon in central Mexico. While neither an epidemic nor fish mortalities were reported, the collected killed specimens exhibited clinical signs of disease (e.g., exopthalmia, moderate abdominal distension and haemorrhaging, as well as internal haemorrhages and adhesions). Histological results of injuries were consistent with the pathology caused by SVCV. This finding was supported by the isolation of a virus in EPC and BF‐2 cells and subsequent RT‐PCR confirmation of SVCV. The phylogenetic analyses of partial SVCV glycoprotein gene sequences classified the isolates into the Ia genogroup. These findings make this the first report of SVCV detection in Mexico, extending the southern geographical range of SVCV within North America. However, since this pathogen was detected in fish inhabiting a natural body of water without tributaries or effluents, it is difficult to estimate the risk of SVCV for other wild/feral cohabitating cyprinid species in the lagoon. The status of this virus is also unknown for other bodies of water within this region.     

Top predators in the Southern ocean: a major leak in the biological carbon pump

Primary productivity in the Southern Ocean is approximately 3.5 gigatons of carbon per year, which accounts for nearly 15 percent of the global total. The presence of high concentrations of nitrate in Antarctic waters suggests that it might be possible to increase primary production significantly and thereby alleviate the net accumulation of atmospheric carbon dioxide. An analysis of the food web for these waters implies that the Southern Ocean may be remarkably inefficient as a carbon sink. This inefficiency is caused by the large flux of carbon respired to the atmosphere by air-breathing birds and mammals, dominant predators in the unusually simple food web of Antarctic waters. These top predators may transfer into the atmosphere as much as 20 to 25 percent of photosynthetically fixed carbon.     

Evaluating the upper thermal limits of glochidia for selected freshwater mussel species (Bivalvia: Unionidae) in central and east Texas,and the implications for their conservation

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