IGF-I Medium Supplementation Improves Singly Cultured Cat Oocyte Maturation and Embryo Development In Vitro

Embryo production is a routine procedure in several species. However, in felids, the effectiveness of this approach is far behind that in the majority of laboratory species. The development of a suitable environment starts with the proper composition of culture media. Therefore, for the improvement of assisted reproduction techniques and their outcome in cats, this is an urgent task. As the addition of insulin-like growth factors (IGF-I, IGF-II) or granulocyte-macrophage colony-stimulating factor (GM-CSF) was beneficial in other mammalian species, this study aims to check whether these components, combined with other factors (such as type of fertilisation or type of culture) can provide a benefit in the felid culture system in current use. Thus, these supplements, in different concentrations and combinations, were merged with the use of two fertilisation techniques and randomly assigned to single or group culturing. The results showed that the addition of IGF-I and/or GM-CSF produced an increase in morula and blastocyst rate in a single culture system. In particular, the supplementation with 20 ng/mL of IGF-I incremented the maturation rate by 10% and significantly increased the morula and blastocyst rates in single culturing. This result is especially remarkable for wild felids, where only a few oocytes and/or embryos are available.

METHODS OF REGULATING PHYSICAL PROPERTIES OF DOUGH USING PHYTOEXTRACTS

This paper considers the prospects of using phytomaterials to solve the problems of baking industry, caused by the instability and defects of wheat flour, and analyses the main methods of regulating structural and mechanical properties of wheat dough and improving the quality of products made from weak flour. The prospects of using phytomaterials as natural alternatives to synthetic additives and baking improvers are presented. The chemical composition and the content of active substances in rosehips (the dogrose fruit) and hawthorn fruit are analyzed as to their effect on increasing the nutritional value and improving the protective properties of products as well as their effect on the course of the technological process, the quality of semi-finished and finished products. The methods of processing the phytomaterials have been suggested, and the optimum parameters of their extraction have been determined as to their effect on the protein-proteinase complex. Water and milk whey are suggested as extractants with the 1:10 ratio between the raw materials and the extractant, while the optimal temperature (100°C) and duration (60 minutes) of extraction were determined experimentally. Rational doses of phytoextracts have been found on the basis of their influence on gluten elasticity and the physical properties of wheat dough during its mixing and fermentation (30% of the rosehip water extract, 45% of hawthorn water extract, and 15% of whey extracts to the weight of flour). It has been established that proposed phytoextracts can increase the water absorption capacity of flour with weak and medium-strength gluten during dough mixing, improve its formation, stability, and elasticity, and decrease the degree of dilution according to the study of rheological properties of the dough using farinograph and extensograph. The mechanism of interactions and conformational changes in the structure of gluten proteins with the active substances of phytoextracts, especially pectins, polyphenols, and organic acids, has been suggested. It has been proven that fruit phytoextracts can be used as alternatives to synthetic improvers to process weak flour. Their usage allows solving the problems of regulating the properties of the gluten network and obtaining baked products with high physical, chemical, and sensory qualities. The proposed methods are effective and relatively easy to implement, which is important for small bakeries and restaurant establishments.

Sperm cryopreservation in the Far-Eastern wildcat (Prionailurus bengalensis euptilurus)

The Far-Eastern wildcat (Prionailurus bengalensis euptilurus) is a rare and poorly investigated nondomestic felid species. An attempt of freezing and cryopreserving Far-Eastern wildcat spermatozoa in CaniPlus Freeze (CPF) medium is reported. Sperm was collected by electroejaculation from five adult Far-Eastern wildcat captive-born males. Epididymal spermatozoa from five adult randomly bred domestic cat males were used as a reference. The viability of frozen-thawed spermatozoa evaluated by double staining with SYBR Green I and PI followed by the subsequent confocal laser scanning microscopy (CLSM) was 38.2% ± 3.0% for the domestic cat and 38.0% ± 10.2% for the Far-Eastern wildcat. The motility of frozen-thawed spermatozoa was 30.8% ± 9.8% for the domestic cat and 33.7% ± 15.1% for the Far-Eastern wildcat. Sperm morphology was assessed by light microscopy. The total percentage of normal spermatozoa after freezing and thawing was 51.9 ± 5.9 for the domestic cat and 55.0% ± 6.4% for the Far-Eastern wildcat. Defects of flagella were the most frequently observed abnormalities in both species (32.2% ± 4.8% and 30.8% ± 4.4% of all reported anomalies for the domestic cat and Far-Eastern wildcat, respectively). Domestic cat epididymal and Far-Eastern ejaculatory spermatozoa fertilized in vitro-matured oocytes of the domestic cat (30.0% ± 5.5% and 35.5% ± 15.0%, respectively). Taken together, these results suggest that the freezing of Far-Eastern wildcat spermatozoa with CPF medium is a suitable method for Felidae cryopreservation.