Evaluation of hematological,biochemical and oxidative stress profile in calves under propofol anesthesia

Veterinary Research Communications - Propofol is a widely used drug in veterinary medicine to induce anesthesia; as well as the chosen compound for protocols of intravenous anesthesia. The present...     

Effect of submerged time of collector ropes on the settlement capacity of Mytilus galloprovincialis L.

Submersion time of collector ropes influences settlement and larval metamorphosis of Mytilus galloprovincialis, which might be related to the biofilm development. In the present study, the effect of submersion time of collector ropes on the settlement of mussel seed was studied. The results of two experiments performed in an experimental long‐line in the Ría de Ares‐Betanzos have established a minimum submersion time of 41–46 days.     

Carcass traits and meat quality of Texel lambs raised in Brachiaria pasture and feedlot systems

Our hypothesis suggests an improvement in carcass and meat quality of pasture‐finished animals by introducing concentrate feed into diets. This study aimed to evaluate the effect of different levels of protein‐energy supplementation on carcass and meat characteristics of Texel lambs raised on Brachiaria pastures, and compare the results with those obtained from confined animals. Thirty 2‐month‐old intact lambs were divided into five treatments: pasture with mineral supplementation, pasture containing daily supplies of 0.8, 1.6, and 2.4% BW protein‐energy supplementation, and confinement (reference treatment). All animals were slaughtered 104 days after the beginning of the experiment. Lambs submitted to 1.6% and 2.4% BW supplementation presented similar characteristics to animals kept in confinement and were superior to animals treated with 0 or 0.8% of BW supplementation levels (p < .05). Increases of subcutaneous fat thickness were verified for 0.0, 0.8, 1.6, 2.4% BW, and confinement treatments, being respectively of 0.25, 0.74, 1.61, 1.69, and 1.98. Conversely, treatments had no influence on meat physical‐chemical characteristics, being all considered moderately soft, juicy (tender), and with mild tastes and odors. Lambs raised on Brachiaria pastures have high‐quality meat, but more protein‐energy supplementation is needed to be an alternative for the feedlots for young animals.     

Maximum compactibility of Argentine soils from the Proctor test; The relationship with organic carbon and water content

Soil compaction is recognized as an increasingly challenging problem for the agricultural, horticultural and forest production in many climatic regions. The Proctor test provides a standardized method to study compactibility of disturbed soils over a range of soil water contents. The objectives of our study were: (a) to determine values of the critical water content for compaction and maximum bulk density from Proctor compaction curves for soils different in their properties; (b) to study the correlation between the maximum bulk density and readily available soil properties. Thirty soil samples were taken from six different locations in Argentina between 58 and 64°W and 34 and 38°S. The degree of saturation at maximum bulk density varied from 73.2 to 96.8%. Comparison of our data with data of two studies in USA showed that relationships between the maximum bulk density and the critical water content were similar to these studies. However, the slope of the relationship between the maximum bulk density and the organic carbon content was 50% less in our study as compared with the two others. The maximum bulk density was highly correlated with the organic carbon content and the silt content, the determination coefficient of the multiple linear regression, r², was 0.88.     

Settlement and recruitment patterns of Mytilus galloprovincialis L. in the Ría de Ares-Betanzos (NW Spain) in the years 2004/2005

The present study explores the settlement and recruitment capacity of Mytilus galloprovincialis L. on artificial collectors in the Ría de Ares‐Betanzos (Galicia, NW Spain) in 2004 and 2005 following standard industrial techniques. Three locations in the ría (Arnela, Redes and Miranda) were selected to investigate larvae settlement after the main spawning event (July 2004/2005). Assessment of the recruitment capacity was performed in autumn (September 2004/2005) when mussel seed is usually gathered from the collector ropes and introduced into industrial cultivation at low densities. For both years, the highest settlement densities were recorded at the most seaward location, Miranda. Differences in settlement densities between locations are discussed in terms of the water circulation regime in the ría and the local hydrographic conditions. In 2004, statistical differences in post‐settlement mortality resulted in similar recruitment densities at Arnela and Miranda, which were higher than at Redes. In 2005, recruitment densities in Redes and Arnela could not be assessed because predators (Spondyliosoma cantharus L.) eliminated the settled population at these locations. Site‐specific differences in recruitment density may be attributed to the environmental limitations of each location as well as intra‐specific competition.     

Evaluation of Anti-Nociceptive and Anti-Inflammatory Activities of a Heterofucan from Dictyota menstrualis

Fucan is a term that defines a family of homo- and hetero-polysaccharides containing sulfated l-fucose in its structure. In this work, a heterofucan (F2.0v) from the seaweed, Dictyota menstrualis, was evaluated as an antinociceptive and anti-inflammatory agent. F2.0v (20.0 mg/kg) inhibits 100% of leukocyte migration into the peritoneal cavity after chemical stimulation. However, F2.0v does not alter the expression of interleukin-1 beta (IL-1β) and interleukin-6 (IL-6), as well as tumor necrosis factor alpha (TNF-α). F2.0v (20.0 mg/kg) has peripheral antinociceptive activity with potency similar to dipyrone. On the other hand, it had no effect on pain response on the hot plate test. Confocal microscopy analysis and flow cytometry showed that F2.0v binds to the surface of leucocytes, which leads us to suggest that the mechanism of action of anti-inflammatory and antinociceptive F2.0v is related to its ability to inhibit the migration of leukocytes to the site of tissue injury. In summary, the data show that F2.0v compound has great potential as an antinociceptive and anti-inflammatory, and future studies will be performed to further characterize the mechanism of action of F2.0v.     

Sensitivity of fractal parameters of soil aggregates to different management practices in a Phaeozem in central Argentina

Changes in soil structure often accompany changes in management practices and may affect the effectiveness of these practices. Parameters are needed to quantify these changes. Our objective was to see if fractal dimensions derived from ‘aggregate bulk density–aggregate size’ and ‘aggregate number–aggregate size’ relationships could be applied to quantify such changes. The study was conducted at the Experimental Farm of the School of Agronomy and Forestry Engineering, National University of La Plata, Argentina. A Vertic Phaeozem soil was sampled at seven locations differing in long-term management practices. The ‘aggregate bulk density–aggregate size’ and ‘number of aggregates–aggregate size’ data were obtained for seven ranges of aggregate sizes. Differences in treatments were reflected by the fragmentation fractal dimension but not the mass fractal dimension. The lowest fragmentation fractal dimensions corresponded to plots under long-term no-tillage and the highest to plots with a history of cultivation of rice (Oryza sativa L.) under water. The fragmentation fractal dimension reflected the differences in soil management whereas the mass fractal dimension appeared to be insensitive to those differences.     

Assessment of spat collector ropes in Galician mussel farming

The large amount of mussel seed required to support the present mussel farming production levels in Galicia (NW Spain) forces the development of new designs in artificial spat collectors for continual improvement of mussel seed gathering. In the present study, we have assessed both settlement and recruitment of Mytilus galloprovincialis on four different collector ropes in the Ría de Ares-Betanzos (Galicia). Besides the traditional collector ropes (lacing without loops and non-filamentous structure; NF-NL), three new rope designs with different lacing and structures were evaluated; ropes with a filamentous loop complement (F-L), ropes with a non-filamentous loop complement (NF-L) and filamentous ropes without loops (F-NL). Ropes with loops showed higher settlement densities (53,925 ± 4625 and 42,433 ± 5525 indiv./m for F-L and NF-L, respectively) than ropes without loops (26,475 ± 3875 and 13,033 ± 1136 indiv./m for F-NL and NF-NL, respectively). This may be explained by the increase in available surface area provided by the loops. Several studies recognized the importance of filamentous substrata for mussel spat settlement, which may help to explain greater settlement densities on filamentous structures between ropes with the same lacing. In recruitment evaluation, ropes with filamentous loops showed the highest densities expressed in indiv./m (5493 ± 587) as was the case of settlement. However, when density was expressed in kg/m, the ropes with non-filamentous loops had a higher yield (8.48 ± 0.22 kg/m), that could be a result of differences in adjusted shell length between ropes. Intra-specific competition and predation were identified as important factors affecting post-settlement mortality. The latter factors could also influence population length distribution. Ropes with rigid loops (NF-L) may supply refuges for spat from predators and therefore, enhance the recruitment of larger individuals, although other factors like size selective settlement could play a significant role in this result.     

Identification of porcine macrophages with monoclonal antibodies in formalin-fixed,paraffin-embedded tissues

Here we report the successful use of monoclonal antibodies (mAbs) BL1H7, BA1C11 (anti-SWC3) and 4E9 for immunohistochemical identification of macrophages in formalin-fixed, paraffin-embedded porcine tissues. Retrieval of antigen reactivity was achieved by heating the slides in a domestic pressure cooker, which makes the technique suitable for the routine laboratory. This method allows to perform retrospective studies in routinely processed tissues and may be useful to investigate the role of macrophages in different pathological processes.