Efficacy of Organic Selenium from Se-Enriched Yeast on Selenium Transfer from Sows to Piglets

Svoboda M., R. Ficek, J. Drábek: Efficacy of Organic Selenium from Se-Enriched Yeast on Selenium Transfer from Sows to Piglets. Acta Vet. Brno 2008, 77: 515-521. The aim of the trial was to determine the efficacy of organic Se from Se-enriched yeast in placental transfer to piglets in the conditions of a Czech pig farm. In group I (n = 8) the sows were fed during gestation and lactation a diet supplemented with inorganic Se (sodium selenite, 0.3 mg/kg of Se for the gestation and 0.38 mg/kg of Se for the lactation diet). In group II (n = 8) the diet of the sows was supplemented with organic Se from Se-enriched yeast (0.3 mg/kg of Se for the gestation and 0.38 mg/kg of Se for the lactation diet). Se concentrations in the whole blood, colostrum and milk were higher (P < 0.01) in the group of sows fed with the organic Se form. No differences in GSH-Px activities in the whole blood were found between the two groups of sows. The concentrations of Se in piglet tissues (heart P < 0.05, liver P > 0.01, muscle P > 0.01) were also higher when the organic form was provided. It is concluded that the use of the organic Se from Se-enriched yeast in sows resulted in greater transfer of Se to their progeny, however it did not have a positive effect on the antioxidant system of the organism. Inorganic selenium, glutathione peroxidase, colostrum, milk For swine, selenium is an essential nutrient. It is principally available to the young pig from both placental and mammary transfer (Mahan et al. 1977). Selenium is an important component of the enzyme glutathione peroxidase (Tappel 1974). Several studies have demonstrated that the selenium status of pigs at birth can be affected by dietary Se concentration and the source of Se (Mahan et al. 1974; Mahan 2000; Mahan and Peters 2004). It has been shown that the Se content in newborn piglet tissues and sow colostrum was higher when organic vs. inorganic Se was fed (Mahan and Kim 1996). The sows fed organic Se had also a higher Se status than sows fed inorganic Se (Mahan 1994). Also studies performed on growing-finishing pigs (Mateo et al. 2007) demonstrated that the inorganic Se was not as effective in accumulating Se in tissues as organic Se. Organic Se from Se-enriched yeast was used in our study. Selenium from Se-enriched yeast has a high bioavailability which can be explained by the composition of seleno-amino-acid analogues, the major one being selenomethionine (Schrauzer 2000). Selenomethionine (Se-Met) can be incorporated directly into body proteins in place of methionine (Me), because tRNA Met does not discriminate between Me and Se-Met (McConnell and Hoffman 1972). The use of Se-enriched yeast has been documented mainly by North American authors (Mahan et al.1975; Mahan et al. 1977; Mahan and Peters 2004; Yoon and McMillan 2006). However, conditions that can influence the need and utilisation of Se in swine are different in the Czech Republic (breeds of sows, their reproductive performance, growth intensity of piglets, composition of diets, strain of Se-enriched yeast). Therefore, we decided to undertake a trial in order to evaluate the efficacy of organic Se in sows and their progeny under the conditions of a Czech pig farm. ACTA VET. BRNO 2008, 77: 515-521; doi:10.2754/avb200877040515 Address for correspondence: MVDr. Martin Svoboda, Ph. D. University of Veterinary and Pharmaceutical Sciences Palackého 1-3, 612 42 Brno Czech Republic Phone: +420 541 562 433 Fax: + 4205 748 841 E-mail: [email protected] http://www.vfu.cz/acta-vet/actavet.htm Materials and Methods Experimental conditions A total of 16 pregnant third parity sows (Landrace × Czech Large White) were used in our study. The sows were divided into two groups and fed gestation and lactation diets composed of the basal diet and different forms of Se supplements. The basal diet contained 0.085 mg/kg of Se in case of the gestation diet, and 0.057 mg/kg of Se in case of the lactation diet. Group I (8 sows) received a feed mixture supplemented with inorganic Se (as sodium selenite, 0.3 mg/kg of Se for the gestation and 0.38 mg of Se for the lactation diet). Group II (8 sows) had gestation and lactation diets supplemented with organic selenium in the form of Seenriched yeast (0.3 mg/kg of Se for the gestation and 0.38 mg of Se for the lactation diet). The Se from Se-enriched yeast Sel-Plex (Alltechnology CZ s.r.o) was used in our study. Gestation diet was provided at 2.5 kg daily during the gestation period. Sows were fed ad libitum during the lactation period. Compositions of gestation and lactation diets are presented in Tables 1 and 2. At the age of 3 days the piglets were injected i.m. with 200 mg of Fe (iron dextran, Ferridextran 10% Spofa). Sampling and analysis Colostrum was collected by hand expression from several glands. Milk was obtained on day 14 after i.v. injection (5 i.u.) of oxytocin. The collected colostrum and milk was frozen and stored for later determination of Se content. Two neonatal piglets from each litter were randomly selected, killed prior to colostrum consumption and tissue samples were collected (liver, heart, gluteal muscles). On days 3 and 14 the sows and piglets were blood-sampled from anterior vena cava. The sows were bled also on day 1 and on day 60 of gestation. Concentrations of Se in the colostrum, whole blood and piglet tissues (heart, liver, gluteal muscles) were measured using the following steps: samples of the whole heparinised blood were mineralised in a closed system using a microwave (MLS-1200, Milestone, Italy) digestion technique with HNO3 and H2O2. Samples were evaporated and the mineral residue was dissolved in water to which 20% HCl was added. Selenium was then determined with Solar 939 AA Spectrometer (Unicam, UK) using a hydride AAS technique. Whole blood glutathione peroxidase (GSH-Px) activities were determined according to the method of Paglia and Valentin (1967) using the test kit RANSEL (Randox Laboratories, Ltd., United Kingdom). Statistical analyses The results were evaluated statistically by Student’s t-test. The experiment was approved by Ethics Commitee of the University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic.