Alfredo Manuel Franco Pereira

Effect of condensed tannin ingestion in sheep and goat parotid saliva proteome

Saliva appears as a defence mechanism, against potential negative effects of tannins, in some species of animals which have to deal with these plant secondary metabolites in their regular diets. This study was carried out to investigate changes in parotid saliva protein profiles of sheep (Ovis aries) and goats (Capra hircus), induced by condensed tannin ingestion. Five Merino sheep and five Serpentina goats were maintained on a quebracho tannin enriched diet for 10 days. Saliva was collected through catheters inserted on parotid ducts and salivary proteins were separated by two-dimensional gel electrophoresis. Matrix-assisted Laser desorption ionization - time of flight (MALDI-TOF) and liquid chromatography tandem mass spectrometry (LC-MS/MS) were used to identify the proteins whose expression levels changed after tannin consumption. Although no new proteins appeared, quebracho tannin consumption increased saliva total protein concentration and produced changes in the proteome of both species. While some proteins were similarly altered in both species parotid salivary protein profile, sheep and goats also presented species-specific differences in response to tannin consumption.

In vitro studies of multiwalled carbon nanotube/ultrahigh molecular weight polyethylene nanocomposites with osteoblast-like MG63 cells

Carbon nanotubes are highly versatile materials; new applications using them are continuously being developed. Special attention is being dedicated to the possible use of multiwalled carbon nanotubes in biomaterials contacting with bone. However, carbon nanotubes are also controversial in regards to effects exerted on living organisms. Carbon nanotubes can be used to improve the tribological properties of polymer/composite materials. Ultrahigh molecular weight polyethylene (UHMWPE) is a polymer widely used in orthopedic applications that imply wear and particle generation. We describe here the response of human osteoblast-like MG63 cells after 6 days of culture in contact with artificially generated particles from both UHMWPE polymer and multiwalled carbon nanotubes (MWCNT)/UHMWPE nanocomposites. This novel composite has superior wear behavior, having thus the potential to reduce the number of revision hip arthroplasty surgeries required by wear failure of acetabular cups and diminish particle-induced osteolysis. The results of an in vitro study of viability and proliferation and interleukin-6 (IL-6) production suggest good cytocompatibility, similar to that of conventional UHMWPE (WST-1 assay results are reported as percentage of control +/- SD: UHMWPE = 96.19 +/- 7.92, MWCNT/UHMWPE = 97.92 +/- 8.29%; total protein: control = 139.73 +/- 10.78, UHMWPE = 137.07 +/- 6.17, MWCNT/UHMWPE = 163.29 +/- 11.81 microg/mL; IL-6: control = 90.93 +/- 10.30, UHMWPE = 92.52 +/- 11.02, MWCNT/UHMWPE = 108.99 +/- 9.90 pg/mL). Standard cell culture conditions were considered as control. These results, especially the absence of significant elevation in the osteolysis inductor IL-6 values, reinforce the potential of this superior wear-resistant composite for future orthopedic applications, when compared to traditional UHMWPE.

Effects of high-fat diet on salivary α-amylase, serum parameters and food consumption in rats

Salivary α-amylase, a major protein in saliva, has been described as a marker of sympathetic nervous system activity, hence for metabolic energy balance. In this context, its expression in overweight and obesity is of interest. Rats fed with a diet enriched with sunflower oil differentially gained weight yielding two subgroups according to their susceptibility (OP) or resistance (OR) to obesity. Elevated plasmatic levels of leptin in the OP subgroup and altered plasmatic lipid profiles (lower triglycerides and higher total cholesterol/high-density lipoprotein (HDL) ratio compared to controls) in the OR subgroup were observed. Animals from the OP subgroup presented higher α-amylase expression and activity even prior to the dietary treatment, suggesting that this salivary protein may constitute a putative indicator of susceptibility for fat tissue accumulation. After 18 weeks of high-fat diet consumption, salivary α-amylase levels did not significantly change in the OP subgroup, but increased 3-fold in the OR subgroup. The increase in α-amylase levels for the latter might represent an adaptation to lower starch intake. These results suggest that salivary α-amylase secretion might be useful to predict susceptibility for weight gain induced by high-fat diet consumption.

Interactions of long-line fishing with seabirds in the south-western Atlantic Ocean, with a focus on White-capped Albatrosses (Thalassarche steadi)

Abstract We analyse the interactions of seabirds with the Uruguayan long-line fishing fleet in the south-western Atlantic Ocean, with a focus on White-capped Albatrosses (Thalassarche (cauta) steadi). The aim of this work is to determine the species composition of the incidental by-catch of seabirds and assess the importance (in terms of abundance) of White-capped Albatross in the seabird assemblage attending this fishery. Counts of seabirds associated with fishing vessels (n =132 counts) were made during five commercial fishing trips in Uruguayan waters, and the incidental by-catch of seabirds per line-set (n = 44 line-sets) was recorded. Of 25 species of seabird recorded in association with the vessels, five were incidentally caught on long-lines. The relative frequency of occurrence of shy-type albatrosses (cauta-type) observed was 25% and their abundance was in the range 0–20 birds; most birds seen were immatures. The three specimens of shy-type albatrosses caught, along with two other specimens caught by the fleet in 2004, were identified by molecular analysis. All were confirmed to be White-capped Albatrosses, suggesting this species is the predominant one among the shy-type albatrosses occurring in the region. Before this study, there was little information on seabirds for this region of the south-western Atlantic Ocean and it was not included in the distribution of the White-capped Albatross. However, the results of this study confirm its occurrence in this region, expanding its global range and show that it is exposed to pelagic long-line fisheries in this part of the Atlantic.

Molecular analysis suggests the occurrence of Shy Albatross in the south-western Atlantic Ocean and its by-catch in longline fishing

Abstract Albatrosses are killed or injured through by-catch in longline fisheries and by collisions with warp cables in trawl fisheries. Detection of areas where albatrosses interact with fisheries is important for their conservation. Shy (Thalassarche cauta) and White-capped (T. steadi) Albatrosses are difficult to study from vessels as they are phenotypically similar. However, the two species can be identified by molecular analysis. The six-fold difference in the size of the total populations of these two species could mask by-catch of the less-abundant Shy Albatross, particularly when available sample sizes of by-catch are small. Here we document the species of a sample of 29 shy-type albatrosses killed as fisheries by-catch to confirm the observation that White-capped Albatrosses are the dominant shy-type albatross in the south-western Atlantic Ocean and exposed to the pelagic longline fishery there. Using a test based on a single nucleotide polymorphism (SNP) previously reported in the mtDNA of both species, 28 specimens were identified as White-capped Albatross. The SNP test and phylogenetic analyses suggested that the remaining bird was a Shy Albatross. Further analyses with other independent markers could confirm the identification of the latter. This result indicates the possibility that Shy Albatrosses reach the southwestern Atlantic Ocean. There is no doubt that White-capped Albatrosses, which are a regular visitor to Uruguayan waters, is the predominant shy-type albatross in the south-western Atlantic. However, a small proportion of shy-type albatrosses in this region could be Shy Albatross but further analysis is needed to confirm this.

Implementation of an efficient muscle fatigue model in the framework of multibody systems dynamics for analysis of human movements

The aim of this study is to implement and integrate a novel and versatile muscle fatigue model in an existing multibody formulation with natural coordinates. The equations of motion of the formulation are rearranged to deal with muscle actuators as externally concentrated forces instead of being considered as kinematic muscle actuator drivers. A muscle fatigue model, originally developed to predict the endurance time of the main body joints, is included in the multibody formulation. The model stems from the compartment theory and uses a bounded controller to rule the rate of motor units changing between the three compartments (resting, activated, and fatigued) that made up the model. The resulting formulation is applied to two example cases involving the human upper extremity, with redundant muscles, to evaluate its robustness and accuracy. Results showed that the proposed methodologies are a valid approach for the calculation of the redundant muscle forces in the presence of muscular fatigue.

A device to improve the Schleger and Turner method for sweating rate measurements

The objective of this study was to test a device developed to improve the functionality, accuracy and precision of the original technique for sweating rate measurements proposed by Schleger and Turner [Schleger AV, Turner HG (1965) Aust J Agric Res 16:92–106]. A device was built for this purpose and tested against the original Schleger and Turner technique. Testing was performed by measuring sweating rates in an experiment involving six Mertolenga heifers subjected to four different thermal levels in a climatic chamber. The device exhibited no functional problems and the results obtained with its use were more consistent than with the Schleger and Turner technique. There was no difference in the reproducibility of the two techniques (same accuracy), but measurements performed with the new device had lower repeatability, corresponding to lower variability and, consequently, to higher precision. When utilizing this device, there is no need for physical contact between the operator and the animal to maintain the filter paper discs in position. This has important advantages: the animals stay quieter, and several animals can be evaluated simultaneously. This is a major advantage because it allows more measurements to be taken in a given period of time, increasing the precision of the observations and diminishing the error associated with temporal hiatus (e.g., the solar angle during field studies). The new device has higher functional versatility when taking measurements in large-scale studies (many animals) under field conditions. The results obtained in this study suggest that the technique using the device presented here could represent an advantageous alternative to the original technique described by Schleger and Turner.

Tree influence on soil and pasture: contribution of proximal sensing to pasture productivity and quality estimation in montado ecosystems

ABSTRACT Montado is a silvo-pastoral ecosystem of the Mediterranean region, a mixed system of trees and pasture, subject to animal grazing. Farmers need information on pasture production and quality in order to assess the direct effect of tree presence on the productivity of their pastoral system, and to devise management that balances farm production and profitability with sustainable soil management. The main objectives of this work were (1) to evaluate tree influence on soil and pasture parameters and (2) to evaluate the use of proximal sensing techniques that have potential for monitoring aspects related to spatial and temporal variability of pasture productivity and quality in montado ecosystems. Both objectives can support the decision-making process of the farmer. The study field is located in Mitra farm, in Southern Portugal. During October 2015, 24 geo-referenced composite soil samples (12 under tree canopy and 12 outside tree canopy) were collected from the 0.0–0.3 m soil layer. The soil samples were analysed for texture (sand, silt, and clay content), moisture content, pH, organic matter, total nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg), and manganese (Mn). The evolution of the pasture was recorded in the 24 sampling points at five monitoring dates: at the end of autumn (December 2015), at the end of winter (March 2016), and then monthly during spring 2016 (April, May, and June). The following pasture parameters were measured: normalized difference vegetation index (NDVI), capacitance, temperature, green and dry matter, ash, crude protein (CP), and neutral detergent fibre. Soil under tree canopy had significantly higher levels of organic matter, N, P, K, and Mg, and better pasture quality while the pasture productivity was higher outside tree canopy. The correlation between pasture direct measurements and sensor parameters was more consistent between capacitance and pasture productivity and between NDVI and CP. The use of fast and efficient tools associated with geo-referenced systems can greatly simplify the pasture monitoring process, which is the basis for estimating feed availability in the field. The knowledge of biomass quality and quantity is fundamental to support decision-making regarding animal stocking rates and rotation among grazing parcels.

Respostas fisiológicas e comportamentais de vacas Holandesas mantidas em sistema adiabático evaporativo

This study aimed to evaluate the influence of cooling systems, ventilation and nebulization on the physiology and behavior of Holstein cows housed in free-stall during the summer of southeastern Brazil. 20 Holstein cows were subjected to two treatments with and without cooling system. Environmental parameters dry bulb temperature, relative humidity and black globe temperature were also recorded. Rectal temperature and respiratory rate were evaluated at 5h, 9h30min, 11h30min, 13h30min, 16h30min, 18h30min e 21h30min. The behavioral variables recorded were posture and activities from 5h to 21:30h. Statistics we done using the method of least squares means. Despite the statistical differences obtained for the physiological variables, they were not biologically effective and indicated that the animals were in thermal comfort. Animals that had ventilation and nebulization have eaten even during the hottest hours of the day. The cooling system is a strategy that allows greater thermal comfort to animals and therefore can optimize milk production by increasing the dietary intake.

Detection of 70 kDa heat shock protein in the saliva of dairy cows.

This Research Communication describes, for the first time, the detection of HSP70 in saliva of dairy cows. Thermal stress is a major environmental stress that limits animal growth, metabolism, and productivity. The cellular response to heat stress involves the synthesis of heat shock proteins (HSPs), presumably to protect the functional stability of cells at increasing temperatures. HSP70 has been found to be present in cattle blood serum and may also be present in other secretory fluids, such as saliva, as already observed in humans. The aim of this study was to detect heat shock protein HSP70 in bovine saliva. Saliva samples were taken from higher- (n = 5) and lower milk producing (n = 5) Holstein-Friesian cows in summer and in winter for the detection of HSP70. HSP70 concentrations were assayed using the ELISA technique. Salivary HSP70 concentrations ranged from 0·524 to 12·174 ng/ml in cows. Higher salivary HSP70 concentrations were significantly associated with higher milk production and higher environmental temperature, but not with rectal temperature.