A. M. Crespilho

The effect of low-level laser irradiation on sperm motility, and integrity of the plasma membrane and acrosome in cryopreserved bovine sperm.

Background and Objective Freezing changes sperm integrity remarkably. Cryopreservation involves cooling, freezing, and thawing and all these contribute to structural damage in sperm, resulting in reduced fertility potential. Low-level laser irradiation (LLLI) could increase energy supply to the cell and cause reactive oxygen species reduction (ROS), contributing to the restoration of oxygen consumption and adenosine triphosphate synthesis (ATP) in the mitochondria. Our goal was to analyze the effects of low-level laser irradiation on sperm motility and integrity of the plasma membrane and acrosome in cryopreserved bovine sperm. Study Design/Materials and Methods We analyzed 09 samples of bull semen (Bos taurus indicus), divided into three groups: a control group without laser irradiation, a 4J group subjected to a laser irradiation dose of 4 joules, and a 6J group subjected to dose of 6 joules. Samples were divided for the analysis of cell viability and acrosomal membrane integrity using flow cytometry; another portion was used for motion analysis. Irradiation was performed in petri dishes of 30 mm containing 3 ml of semen by an aluminum gallium indium phosphide laser diode with a wavelength of 660 nm, 30 mW power, and energy of 4 and 6 joules for 80 and 120 seconds respectively. Subsequently, the irradiated and control semen samples were subjected to cryopreservation and analyzed by flow cytometry (7AAD and FITC-PSA) using the ISAS - Integrated Semen Analysis System. Results Flow cytometry showed an increase in the percentage of live sperm cells and acrosome integrity in relation to control cells when subjected to irradiation of low-power laser in two different doses of 4 and 6 joules (p < 0.05). In the analysis of straightness, percentage of cell movement, and motility, a dose of 4 joules was more effective (p < 0.05). Conclusion We conclude that LLLI may exert beneficial effects in the preservation of live sperm. A dose of 4 joules prior to cryopreservation was more effective than a dose of 6 joules in preserving sperm motility.

Effect of the Flunixin Meglumine on Pregnancy Rates in an Equine Embryo Transfer Program

ABSTRACT During the equine embryo transfer (ET), manipulation of the recipients cervix can stimulate the release of prostaglandin F2&agr; by the uterine environment. Nonsteroidal anti‐inflammatory drugs such as flunixin meglumine (FM) are frequently used in order to prevent a potential luteolysis. However, despite the reduction of inflammatory reaction and release of prostaglandins, the benefits of FM in pregnancy rates (PRs) of mares submitted to ET are not conclusive, and there is no information about the early pregnancy loss (EPL) rate after FM injection. The objective of this study was to evaluate the effect of FM in the PR and EPL in embryo‐recipient mares. The data from 409 ET from a commercial breeding center were used, which 179 mares formed the control group (CG) and 230 recipients received the treatment of FM 1.1 mg/kg immediately after ET. There was no difference (P > .05) in PRs at 15 days (70.95% in the CG and 75.22% in treated mares) and 60 days (65.92% in CG and 65.22% in FM treated mares). However, there was a trend in the increase of early the pregnancy loss rate in mares that received FM (P = .0852). From the results of the present experiment, FM does not improve the PR in embryo‐recipient mares. HighlightsThe embryonic prostaglandins activate mobility mechanism in the entire uterine lumen, essential to maternal recognition of pregnancy and the antiluteolytic factor distribution.Nonsteroidal anti‐inflammatory drugs such as flunixin meglumine (FM) suppress prostaglandin production and are frequently used in an equine embryo transfer program to prevent a potential luteolysis.Flunixin meglumine does not improve the pregnancy rate in embryo‐recipient mares.Treatment with FM showed a tendency to increase the pregnancy loss.