CONCENTRAÇÃO DE GLICOSE SANGUÍNEA E RELAÇÃO HETERÓFILO:LINFÓCITO PODEM SER UTILIZADOS COMO INDICADORES DE ESTRESSE TÉRMICO PARA AVES POEDEIRAS?

Aves em estresse calórico apresentam alterações fisiológicas e metabólicas para a manutenção de sua homeostase. O sistema sanguíneo é sensível a essas mudanças e a relação heterófilo:linfócito e a concentração de glicose são consideradas importantes índices de estresse crônico em aves. O objetivo da pesquisa foi verificar se a relação heterófilo:linfócito e a concentração de glicose sanguínea de aves podem ser utilizados para inferir sobre o nível de estresse das aves em diferentes condições ambientais. Foram registradas temperatura de bulbo seco, umidade relativa e temperatura de globo negro por meio de termohigrômetros, para a determinação do índice de conforto térmico de dois galpões, sendo um climatizado e outro não climatizado. As amostras de sangue de 15 aves de cada galpão foram coletadas para determinação de glicose e contagem diferencial dos leucócitos. Não houve diferença para o ITGU entre os galpões avaliados. Não se observou associações da concentração de glicose e da relação heterófilo:linfócito com o aumento do ITGU. Nas condições experimentais deste trabalho não foi possível afirmar que os parâmetros sanguíneos concentração de glicose e relação heterófilo:linfócito podem ser utilizados como indicadores de estresse térmico para aves poedeiras.

The effect of eggshell apex abnormalities on table egg quality during storage in 2 seasons of the year

Mycoplasma synoviae infection of hens has been associated with problems of eggshell quality called eggshell apex abnormalities (EAA). Little is known about the quality of EAA eggs from a commercial point of view, especially during their storage. The study aimed to examine the differences between EAA and normal eggs during storage under controlled conditions in 2 seasons, summer and winter, by comparing internal and external quality parameters. In a conventional egg production farm with white laying hens of varying ages in the city of Bastos, state of São Paulo, Brazil, 232 eggs were used in the summer season and 400 eggs in the winter season. Half of the eggs had EAA, and the other half were considered normal eggs for each season. The eggs were analyzed at 2, 7, 14, 21, and 28 d after being laid and stored from 24.6 to 25.8°C in summer and from 24 to 25°C in winter. There was no difference (P > 0.05) in the average egg weight between EAA and normal eggs at any studied time point, but in both seasons, the weight loss in EAA eggs was higher than in normal eggs. The losses in Haugh unit scores from the first to the last measurements were approximately 40% regardless of egg type or season of production. In comparing eggshell thickness, only the apices of the EAA eggs were thinner (P < 0.0001) than normal eggs in the summer, but in the winter, the EAA egg apices (P < 0.0001) and sides (P = 0.03) were both thinner. The presence of EAA did not affect the eggshell weight (P > 0.05) or eggshell percentage (P > 0.05). The eggshell strength of the EAA eggs was lower (P < 0.0001) than normal eggs in both the summer (16.57%) and winter (19.86%). The presence of EAA did not affect the internal quality of the egg, but was related to a greater loss of external quality and weight during storage.

The major circulating immunosuppressive activity in American visceral leishmaniasis patients is associated with a high-molecular weight fraction and is not mediated by IgG, IgG immune complexes or lipoproteins

Opportunistic infections, due to disease-related immunosuppression, constitute the major cause of death in American visceral leishmaniasis (AVL). Sera from these patients (AVL sera) non-specifically inhibit the in vitro proliferative response of normal human lymphocytes to lectins or antigens. In the present work, the mediation of this inhibition by IgG, immune complexes and low- or very low-density lipoproteins was studied. AVL serum fractions containing proteins with the molecular weight of IgG, and IgG, purified from AVL sera by anion exchange chromatography, did not suppress the lymphoproliferation. Most of the suppressive activity of AVL sera was associated with a fraction containing molecules with molecular weights above 430 kDa. This would be compatible with it being due to immune complexes and/or lipoproteins, and not to soluble IL-2 receptors as reported previously. However, neither of the two possibilities seem to be the case, as (1) depletion of immune complexes by protein-A followed by protein-G chromatographies did not affect the serum suppressive activity, (2) no correlation between immune complex contents and suppressive activities in individual sera was observed, and (3) plasma lipoproteins (VLDL and LDL), purified from AVL patients and from healthy individuals, had the same degree of immunosuppressive activity.

Comparison of six methods for the extraction of lipids from serum in terms of effectiveness and protein preservation

The present work compares six biochemical methods for extraction of lipids from human serum. Although some organic solvents were good lipid extractors, they precipitated most of the total proteins and albumin. On the other hand, methodologies using Triton X-114 and silica were efficient for extraction of lipids, while sparing the protein fraction.

An improved anti-C3/IgG ELISA for quantification of soluble immune complexes

A semi-quantitative ELISA for complement-fixing, IgG-containing immune complexes (IC) is described. The assay is based on the insolubilization of IC by polyethyleneglycol, their capture by solid-phase anti-C3 antibodies, reaction with peroxidase-labeled anti-IgG antibodies and incubation with a chromogenic peroxidase substrate. It was markedly improved by the use of a single-step procedure which simultaneously washed and precipitated the insolubilized immune complexes. Intra-assay and inter-assay coefficients of variation were lower than 8.6 and 14.7%, respectively. As expected, higher levels of circulating immune complexes, in relation to healthy individuals, were found in patients with American visceral leishmaniasis (AVL), systemic lupus erythematosus (SLE) and rheumatoid arthritis (RA), with prevalences comparable to those described in the literature. The ELISA can be quickly assembled from reagents and plasticware widely available commercially, detects immune complexes fulfilling three different criteria and is more sensitive than a previously published method based on the same principles (detection limit for complement-sensitized aggregated IgG of 2 microg ml(-1) as compared with a detection limit above 16 microg ml(-1)).