Efeito dos diluentes pigpel-5 e pigpel-5 plus sobre a qualidade do sêmen suíno acondicionado à 5ºC e 17ºC

Abstract

The use of freezing packages with adjustable thermostat is necessary when we use diluents that are able to keep the quality of the inseminating doses between 15°C and 18°C. However, it is important to consider that these packages are expensive and when submitted to great variation of ambient temperature they present difficulty to keep the internal temperature in the desired amplitude. Besides this, the swine semen storage between 15°C and 18°C limits its transportation, constraining its useful lifetime and allowing bacterial growth. The goal of this study was to evaluate the quality of swine semen preserved in diluent PIGPEL-5, in which we added egg yolk as cryoprotectant and also to evaluate the quality of PIGPEL5 Plus, in which we added low density lipoprotein (LDL), extracted from egg yolk as cryoprotectant. In experiment 1 the inseminating doses were stored using freezing packages at 5°C and 17°C, to compare the results between diluents PIGPEL-5 and PIGPEL5 Plus, and these results related to extensor BTS, packaged at 17°C in order to prove the versatility of the diluent in different storage temperatures. The same diluents were tested in experiment 2, using commercial fridge and semen freezing package, both at 5°C, in order to prove the efficacy of the tested diluents when they are kept in fridges without severe control of temperature. In both experiments motility tests, sperm morphology and functional integrity of membrane through hypoosmotic shock were accomplished. In experiment 1, diluent PIGPEL-5 kept its sperm motility at 5°C and at 17°C, especially until 48h of packaging, not showing any benefit when LDL was added. As for hypoosmotic shock, the diluent PIGPEL5 Plus at 17°C was superior (P<0,05) in the 48h than PIGPEL-5 at 17°C and BTS. The percentage of sperms with normal morphology did not differ (P>0,05) between the different diluents as from 0h of packaging. As for the use of commercial fridge (experiment 2), the results did not differ between the tested diluents (P>0,05). The effectiveness of PIGPEL-5 when packaged at 5°C and 17°C with egg yolk (PIGPEL5 Plus) keeping the sperm quality in the motility tests, sperm morphology and functional integrity of the membrane was demonstrated. The possibility of its use both in freezing package and in commercial fridge was also demonstrated.