ABSTRACT:The objective of this study was to evaluate the in vitro efficacy of a topical skin cream containing a mixture of emu oil, jojoba oil, avocado oil, and tea tree oil against the canine skin pathogens Staphylococcus pseudintermedius and Malassezia pachydermatis. Three S. pseudintermedius isolates from dogs and a type strain of M. pachydermatis were used. Based on the standards of the Clinical and Laboratory Standards Institute, the minimal inhibitory concentration (MIC) and the minimal bactericidal/fungicidal concentration (MBC/MFC) were determined. In addition, microbial inactivation time was determined for both pathogens. The MICs against S. pseudintermedius and M. pachydermatis were 0.23% and 0.63%, while the MBC/MFCs were 7.5% and 5%, respectively. In assessments of the microbial inactivation time, after 12 h of incubation with the cream, the growth of both pathogens was completely inhibited. These results suggest that the skin cream tested here can be used as a substitute for generally used antibiotic/antifungal agents. Keywords: natural oil; Staphylococcus pseudintermedius; Malassezia pachydermatis; antimicrobial effectSupported by High Nature Ltd in 2014 (Grant No. 2013-A012-0038).Superficial skin infections such as superficial pyoderma and otitis externa are commonly encountered in veterinary practice and account for a significant number of antimicrobial prescriptions (Escher et al. 2011). Staphylococcus pseudintermedius and Malassezia pachydermatis are the most common pathogens isolated from pyoderma and otitis externa in dogs (Cafarchia et al. 2005;Fitzgerald 2009). In the last decade, resistance to antimicrobial agents has increased, particularly with the emergence and widespread dissemination of methicillin-resistant S. pseudintermedius in dogs as a result of the broad use of certain antimicrobial agents (Neu 1992;Kadlec and Schwarz 2013). The increased resistance to most available antimicrobial agents has created a need to identify alternative treatment strategies. As one possible alternative, the use of essential oils against various pathogens such as bacteria, virus, fungi, parasites, and insects has been widely evaluated (Weseler et al. 2002;Moon et al. 2006;Prabussenivasan et al. 2006;LaPlante et al. 2007;Wu et al. 2010;Freire et al. 2012;Valentine et al. 2012). These oils contain numerous constituents that contribute to the characteristic odour and medicinal effects, but they are not a usual choice for the treatment of infection, primarily because of the lack of scientific evidence of their efficacy.The objective of this study was to evaluate the in vitro efficacy of a topical skin cream containing a mixture of natural oils against the canine skin pathogens S. pseudintermedius and M. pachydermatis. MATERIAL AND METHODSTest materials. A topical skin cream (Dara cream ® , Koreai1, Kimpo, Korea) containing a mixture of emu oil, jojoba oil, avocado oil, and tea tree oil was evaluated. Ampicillin sodium salt and miconazole nitrate were purchased from Sigma-Aldrich Corp. (St. Louis, MO, USA) a...

Epidermal growth factor (EGF) is a major follicular factor affecting maturation of oocyte in many species. The insulin-like growth factor II (IGF2) gene is an imprinted gene in embryonic development that functions primarily as a regulator of cell growth and differentiation. Thus, this study examined the maturation and developmental ability of in vitro-fertilized (IVF) pig immature oocytes cultured in maturation medium supplemented with EGF. The blastocysts derived from these oocytes were further examined for the expression level of IGF2 as a cell survival activity. Pig immature oocytes were cultured in TCM-199 medium (with no supplement) with or without 10 ng/mL EGF for 42–14 h, and then matured oocytes were co-incubated with 5 × 105 sperm/mL in modified Tris-buffered medium containing 1 mM caffeine sodium benzonate and 0.1% bovine serum albumin (BSA) for 6 h for IVF. Subsequently, embryos were cultured in 50 μL of NCSU-13 containing 0.4% BSA for 7 days at 39°C in a humidified atmosphere of 5% CO2 in air. Total cell numbers in blastocysts were examined by fluorescence staining with Hoescht 33342, and the expression level of IGF2 was analyzed with a fluorescence-monitored quantitative real-time reverse transcriptase-polymerase chain reaction method. We found that pig oocytes matured with EGF showed significant improvement of their development ability (Table 1). Presence of EGF in TCM-199 medium significantly increased (P < 0.05) the rates of maturation, sperm penetration, male pronucleus (MPN) formation, cleavage, and blastocyst formation. Furthermore, blastocysts derived from oocytes cultured with EGF were 24-fold higher in the relative expression level of IGF2 than those without EGF. Therefore, these data suggest that pig oocytes matured in medium supplemented with EGF increases the developmental ability and cell viability during cell divisions following IVF. In conclusion, EGF may increase cytoplasmic as well as nuclear maturation of pig immature oocytes. Table 1. Improvement of developmental ability of pig oocytes matured with EGF This work was supported by the Research Project on the Production of Bio-organs, Ministry of Agriculture and Forestry, Republic of Korea.