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The goal of the experiment was to evaluate susceptibility of lymphocytes populations derived from bursa of Fabricius, spleen, thymus, and blood to temperature treatments in vitro. Temperatures used in study was 37 °C (thermoneutral), 41 °C (mild heat stress) and 45 °C (severe heat stress). Cells were incubated for 8 hours and after 3 and 8 hours were measured numbers of apoptotic, necrotic and CellROX positive cells by flow cytometry. Representation of live lymphocyte phenotypes (CD3, CD4, CD8, BU1) in cell populations were also measured. At all temperature treatments, thymus lymphocytes population had the lowest (p < 0.05) percentage of apoptotic cells. On the other hand, significantly highest numbers (p < 0.05) of apoptotic cells were found in bursal lymphocytes after 8 hours of incubation. Differences in numbers of necrotic cells were more pronounced at 45 °C, where after 3 and 8 hours of incubation were significantly highest numbers (p < 0.05) of necrotic cells in spleen. Increasing temperature induce production of reactive oxygen species (ROS) in cells and highest proportion (p < 0.05) of ROS-positive cells were found in bursal and spleen cell population after 8 hours of incubation. Transmission electron microscopy showed loss of mitochondrial matrix and disrupted mitochondrial membrane in mitochondria of lymphocytes at 45 °C as initial damage caused by ROS. From individual cell phenotypes, there were significantly decreased (p < 0.05) B lymphocytes in bursa of Fabricius, CD4+ and CD8+ lymphocytes in thymus and whole T lymphocytes population in spleen at 45 °C. Various susceptibility to temperature can be predictive factor of worse function in some organs in stress conditions where body temperature increase. [ABSTRACT FROM AUTHOR]

Summary: Rabbits are an important animal species for meeting the nutritional requirements of the world's growing population due to the high conversion rate of feed. In most countries, the rabbit industry currently relies on artificial insemination with fresh or chilled and frozen–thawed spermatozoa. Various factors during the freezing process, including diluents, sperm preparation and freezing techniques, antioxidants, sudden temperature changes, ice formation and osmotic stress, have been proposed as reasons for the poor sperm quality post thaw. Despite the extensive progress reached in the field of rabbit sperm cryopreservation, new methodological approaches that could overcome problems in sperm cryopreservation are necessary. The aim of this review was to describe the factors that affect the cryopreservation of rabbit sperm. [ABSTRACT FROM AUTHOR]

This study aimed to examine the effect of dietary flavonoid isoquercitrin on ovarian granulosa cells using the immortalized human cell line HGL5. Cell viability, survival, apoptosis, release of steroid hormones 17ß-estradiol and progesterone, and human transforming growth factor-ß2 (TGF-ß2) and TGF-ß2 receptor as well as intracellular reactive oxygen species (ROS) generation were investigated after isoquercitrin treatment at the concentration range of 5-100 µg.ml-1. It did not cause any significant change (p>0.05) in cell viability as studied by AlamarBlue assay in comparison to control. No significant change was observed (p>0.05) in the proportion of live, dead and apoptotic cells as revealed by apoptotic assay using flow cytometry. Similarly, the release of 17ß-estradiol, progesterone, TGF-ß2 and its receptor were not affected significantly (p>0.05) by isoquercitrin as detected by ELISA, in comparison to control. Except for the highest concentration of 100 µg.ml-1, which led to oxidative stress, isoquercitrin exhibited antioxidative activity at lower concentration used in the study (5, 10, 25, and 50 µg.ml-1) by hampering the production of intracellular ROS, in comparison to control, as detected by chemiluminescence assay (p<0.05). Findings of the present study indicate an existence of the antioxidative pathway that involves inhibition of intracellular ROS generation by isoquercitrin in human ovarian granulosa cells. [ABSTRACT FROM AUTHOR]

In the present study, we aimed to assess antioxidant status in erythrocytes in vitro after patulin (PAT) and epicatechin exposure by measuring antioxidant enzymes (superoxide-dismutase – SOD, glutathione peroxidase – GPx and catalase – CAT) and parameters associated with oxidative stress (malondialdehyde – MDA and ROS). We also investigated the effect of PAT on viability and count of lymphocytes and lymphocyte subpopulations in rabbit blood in vitro. Whole blood of rabbits was used for analysis of antioxidant changes in rabbit erythrocytes after epicatechin and PAT treatment (separately or in combination, at concentrations of 0.2; 2; 20; 200 µg mL–1 of epicatechin and 0.5; 5; 10 µg mL–1 of PAT). Whole blood of rabbits was also used for analysis of count and viability of lymphocytes after PAT treatment at concentrations of 10; 25 and 50 µg mL–1. Results from our experiment confirmed the ability of epicatechin to protect cells against oxidative stress and lipoperoxidation. Our findings indicate that mycotoxin PAT in low concentrations did not affect the activity of antioxidant enzymes in erythrocytes of rabbits significantly. Only slight non-significant changes in lymphocytes count after treatment with low doses of PAT in rabbit blood were observed. [ABSTRACT FROM AUTHOR]

Magnetic-activated cell sorting (MACS) separates apoptotic spermatozoa by the use of annexin V-conjugated nanoparticles which bind to phosphatidylserine that is externalized on the outer leaflet of the sperm plasma membrane. This technique yields two fractions: annexin V-negative (AnV) and annexin V-positive (AnV). The aim of the study was to evaluate the effect of MACS application on the motility parameters of rabbit spermatozoa. Rabbit semen samples collected separately from 4 bucks (I, II, III, and IV) were filtered and separated in a MACS system. The semen samples from a control (untreated) group, AnV and AnV fraction were evaluated using CASA system. The experiment was replicated 4 times for each buck. The AnV sperm had significantly lower concentration than the AnV fractions and the control samples ( P<0.05 for bucks I, II, III, but not IV). We observed that the proportion of apoptotic spermatozoa in the semen of NZW bucks is about 20%. There was no significant difference in the percentage of motile and progressively motile spermatozoa between the AnVfractions and control samples. In conclusion, the MACS technique has no harmful effect on the rabbit sperm concentration and motility. [ABSTRACT FROM AUTHOR]