Natural bee honey and Conservation of drone semen in liquid nitrogen

Purpose: Conducting a honey diluent test for creeples of sperm of a drone honey bee.Materials and methods. The material for the research served a sperm of the milled drone drums of the "Prioksky" type of the Midway breed of bees. The selection of sperm was carried out in June-July 2020 g by the method of artificial stimulation of the turning of the endofalosha in half-armed drones aged 25-30 days. The rock type "Prioksky" of the middle Russian breed of bees. Before freezing, the sperm was stored in glass capillaries in the cooled state at 3 ° C for 2 months. The following composition of the diluent was tested - 10% honey, lactose, sucrose, egg yolk and dimethyl sulfoxide.Results. Studies have shown the viability of sperm at 64.0 ± 1.8% (41.5-83.7), and a total mobility of 2.2 ± 0.6% (0-11.5). To evaluate the fertilizing ability of sperm, carried out artificial insemination of 10 bee modules. In 4 seeded bees dykens, the presence of sperm in a seed-hearter with a concentration of sperm from 0.22-4.4 million / μl is revealed. In paired eggs of three other seeded matters, the presence of sperm and the complete absence of spermatozoa in the seed-receptionist are recorded.Conclusion. Tests of the honey diluent for deep freezing sperm of the drone honey bees in liquid nitrogen confirmed its cryophylactic properties.

Study of the properties of the ovarian fluid of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833) during freezing

The process of freezing the ovarian fluid of the Russian sturgeon (Acipenser gueldenstaedtii Brandt, 1833) was analyzed. With gradual cooling from 22°C to -196°C at a rate of 10° per minute, the process of freezing, formation and change of ice microparticles was observed. The ovarian liquid was glazed at -5°C and only at -70°. With the microparticles of ice began to form. From that moment, up to the temperature of liquid nitrogen (-196°C), the microparticles were crushed into smaller ones. The high content of intracellular water in the ovarian fluid of female Russian sturgeon contributes to the formation of the bulk of microparticles of ice, which is confirmed by their shape. These particles, which have sharp edges, are able to damage the thin shells of eggs during deep freezing.

Effects of long-term deep freezing on human femoral cartilage: differential scanning calorimetric (DSC) analysis and histopathological evaluations

Results from our previous study proved that differential scanning calorimetry (DSC) is a reliable method for qualitative evaluation of morphological changes in human cartilage samples caused by cryopreservation and storage time correlates with graft quality [1, 2]. Our current aim was to specify/characterise the effects of deep-freezing on hyaline cartilage in conjunction with length of storage time. Detailed analysis included DSC and histological measurements which showed distinctive differences. Based on our histological examinations, we could not confirm significant association between cartilage destruction and long-time storage, but the DSC results exhibited a definite change in thermal parameters after the 6th week cryopreservation. A modified and more detailed analysis would be useful to determine the effects of deep-freezing.

Effects of freezing seeds Abutilon theophrasti Medik. and Eruca vesicaria (L.) Cav. for the appearance, growth and development of plants

A comparative study of the effect of different storage regimes of seeds (at + 5 ° С, -20 ° С and under deep freezing conditions at -196 ° С) of two cultivated plants of the Abutilon theophrasti Medik. and Eruca vesicaria (L.) Cav. on their viability and the development of plants from them in the field was carried out. Freezing increases the laboratory and field germination of the seeds of the A. theophrasti and does not significantly affect the germination of the seeds of the A. theophrasti, and also increases the germination energy of the seeds of both plant species. It did not cause the appearance of non-viable, ugly seedlings and plants. Plants went through a full development cycle and set full-value seeds. Biometric parameters of plants obtained from thawed seeds and control ones are very close. Cryopreservation is a promising way of storing seeds of the studied species, since it ensures longer periods of preservation of their viability. Keywords: ABUTILON THEOPHRASTI; ERUCA VESICARIA; SEED BANKS; LONG-TERM SEED STORAGE REGIMES; CRYOPRESERVATION

Veterinary and sanitary assessment and disinfection of refrigerator chambers of meat processing enterprises

The results of microbiological studies of air samples of refrigerating chambers of meat processing enterprises are presented. The quantitative composition of the air microbiota of the chambers of the refrigerating shop was studied. It has been established that the technological regimes for cooling meat in cooled chambers (t = +4 °C) and deep freezing chambers (t = -18 °C and -22 °C) have no bacteriostatic effect on the life activity of mold fungi. The developed disinfecting preparation (hydrogen peroxide (8.0 - 10%), acetic acid (10%), peracetic acid (5.0 - 7.0%), stabilizing additives, water) ensures the destruction of sanitary-indicative microorganisms in cold rooms meat processing plants when applied at a concentration of 0.05% - 60 minutes, 0.1% - 30 minutes, 0.15% - 10 minutes and does not have a toxic effect on meat raw materials that are stored in chambers of the refrigeration shop after disinfection.

Deep freezing to maintain the freshness of pork loin during long-term storage

As storage temperature impacts frozen meat quality, we evaluated the ideal freezing and storage temperatures for pork loin, and effects of long-term storage at − 60, − 50, and − 18 °C on pork loin physicochemical properties. Pork loin was cut into 30 × 30 × 30 mm (50 g) and packed in air-containing box. Thereafter, they were stored at different freezing temperature for 6 months. Frozen pork loins were thawed at 4 °C. Samples frozen at − 18 °C exhibited surface dehydration (at 3 months) and high moisture loss surface dehydration-induced discoloration and toughening. However, samples frozen by deep freezing temperature (− 60 and − 50 °C) had lower values of thawing loss, WHC, and shear force than those of frozen at − 18 °C. Samples frozen at − 60 and − 50 °C maintained their freshness better than those frozen at − 18 °C; samples stored at − 60 °C showed significantly lower VBN than those stored at − 50 °C. Therefore, − 60 °C is suitable for freezing pork loins.