This paper presents the results of a study of spectrum-induced myopia using a model of quail maturation. Using acoustic microscopy methods in the native state, the geometric dimensions of the structural elements of the eye involved in focusing the optical system are determined, and the patterns of their changes as the body grows and during emmetropization are identified. Particular emphasis is placed on the composition, structure, and mechanical properties of the sclera as the main supporting tissue of the eye, responsible for its shape and size.

The present study is an attempt to experimentally create conditions for the development of childhood myopia in laboratory animals. The measurements were taken using ultrasound technique for different age groups of the Japanese quail Coturnix japonica dom. – chicks (10, 25, and 45 days) and mature birds (65 days) in in situ conditions. To simulate the processes of myopization, sources of narrow-spectrum blue (450 ± 50 nm), red (600 ± 50 nm) and yellow (550 ± 50 nm), the most comfortable for the eye, light were used. High-frequency focused ultrasound (30–80 MHz) and the B/Z scanning mode were applied for the high-quality visualization of the fine structure of the chicks' eye in the sagittal plane. The obtained data on the eyeball size, the lens and scleral-cornea, vitreous body and the chorioretinal complex revealed the age-related changes in the animal eye development. Preliminary data on the sclera elasticity of the quail's eye are presented.

Abstract High-resolution ultrasound techniques are employed in ophthalmology for detecting age-related changes in the eyeball’s structure, diagnosing tumours and vascular conditions. Meanwhile, acoustic microscopy methods are widely used in laboratory animal research. Our experiments utilised a short ultrasonic pulse (30-80 MHz) and B/Z-scan mode with dynamic focusing. This study utilised these parameters to measure various ocular dimensions, including the longitudinal and transverse size of the eyeball, the thickness of the lens, and the scleral-cornea, vitreous and chorioretinal complex. The sample comprised individuals of varying ages, an adult bird (65 days), and chicks across four age stages (10, 23, 36, 45 days), all studied in situ. The method enabled observation of age-related alterations in ocular structures throughout the ontogenesis of the animal, illuminated daily using an incandescent lamp alongside yellow and blue light filters. The outcomes illustrate that the measurement technique’s sensitivity detects an anterior-posterior axis (APA) escalation of quail eyes with an error range of ±15 microns. The method’s sensitivity adequately analysed the impact of the spectral composition of everyday lighting on deviations in eye development.

One of the major approaches to studying spaceflight effects on living systems is flying experimental with animals. IBMP is developing scientific equipment for experiments with animals on spacecraft BION-M2. Among numerous aspects of maintaining animals, the most essential is water and type of diet. On BION-M1, mice consumed a paste-like food that caused some undesirable effects. We decided to use dry pellets combined with slightly gelled water (1.5 % carboxymethyl cellulose) that will simplify a drinker substantially. We thought it would be useful to assess the dependence of mice wellbeing on diet under the conditions onboard spacecraft series BION-M. We tested 3 pellets of varying content, and a paste-like food that had been used in the space experiments. For the purpose of testing and gathering the ground control data, a chamber was designed in which microclimate and air composition dynamics imitated those in space missions as close as possible. The 33-day test was performed with 75 adult male white mice Balb/. There was no fundamental difference in the condition of animals fed with pellets and paste-like food. In future, we intend to give mice pallets + gelled water with a useful mass of 8.8 g/day per a mouse. Useful mass of the paste-like food is two times larger, i.e. 16.6 g/day per a mouse. Pattern of microbial contamination looks generally quite steady. What worries is a small increase of contamination of the gelled water pipeline; possible retrograde contamination from the drinker should not be ignored.

The size of a growing child’s eye quickly adjusts to focusing in the dominant spectral band of illumination. The predominant type of lighting plays an important role in the formation of the eyeball in childhood. Everyday use of lamps with whose spectral composition is dominated by the red component can lead to lengthening of the eye (myopia or near-sightedness) during the most critical period of development. These changes may be irreversible. We report measurements of various parameters of the eyes of quail chicks at different ages during the maturation period. Acoustic microscopy was used for measurements. The measurements were made in two groups of birds. Everyday lighting in the first case was with an incandescent lamp and in the second case with an LED lamp with a dominant spectral band of 525–700 nm. The results demonstrate the drawbacks of using incandescent lamps as everyday lighting for children during the formation of the eyeball.

The problem of eye pathologies, such as age-related macular dystrophy and children's myopia, is becoming increasingly relevant every year. The influence of the spectral composition of artificial lighting that accompanies a person from birth to maturity is becoming more noticeable. To identify this pattern, experimental studies are carried out using an effective animal model: the Japanese quail Coturnix japonica, whose domesticated population is widely used as a laboratory animal in ophthalmology and biomedical disciplines. To reveal the difference in the development of eye tissues under everyday light with different spectral characteristics, chicks and adult birds are studied. Optical coherence tomography is used to observe the structure of the anterior part of the eye, as well as the thickness and structure of the retinal-choroidal complex. Data on age-related changes in the eyeball, cornea, anterior chamber, lens, vitreous body, chorioretinal complex, and sclera are obtained using ultrasound methods. The content of melatonin in the tissues of the eye is measured.

Expectation of remote space missions and long-term stay and work on the Moon with the magnetic field 1,000 times weaker than on Earth sets the researchers the formidable task to investigate effects of the hypomagnetic environment on living organisms. The paper reports data about the liver and spleen development in Japanese quail embryos of various age exposed in a modeled lunar magnetic field. Retardation of hemopoiesis was observed as in the first generation embryos (F1), so in sequential embryo generations developed in the ordinary magnetic environment (F2).

One of the crucial issues of handling animals in space flight is availability of food and water supply systems. However, water supply for animal experiments onboard unmanned spacecrafts is a particularly formidable problem. To maintain laboratory mice in space flight, a paste-type food was formulated on the basis of the standard extruded combined food for laboratory rodents (PK-120) with a 18.3% wet protein content and moisture raised to 68%. Food manufacturing technology for rodents reproduces essentially the one for quails that had shown good advantages in an experiment with adult birds aboard orbital complex Mir. The proposed food was tested with white laboratory mice (males and females) of mature 37-d age. According to the data of blood clinical analysis and visceral organs morphology investigations, feeding with the paste-type food without additional water over 21 days did not change the life weight of mice or food digestibility and availability. These biological test results gave go to feed mice in the Bion-M1 and synchronous ground experiments with the paste-type food.

Results of studying spinal marrow histogenesis in age varying Japanese quail embryos and chicklings whose embryonic development took place in microgravity are presented. Histological comparison of spinal cords showed retardation of morphogenetic development, lumber spine especially, in the group of flight embryos manifested as incomplete proliferative activity during migration processes and nervous cell differentiation. Like on earth, in space microgravity chicklings also hatched on day 17 of embryogenesis. Multiform marrow changes in space chicklings were a nervous cells reaction to the functional state of organism in the micro-g environment.

The article reports the results of histogenetic studies of the liver extracted from Japanese quail embryos and hatchlings that had passed the embryonic and postnatal development in microgravity. Comparison of the liver from the flight and laboratory embryos showed identity of organogenesis and histogenesis processes in space and on Earth. However, it should be noted that early histogenetic development of the space embryo liver had been retarded which was concluded from an enlarged lumen in bile capillaries and loose arrangement of epithelium girders as compared with the control On day-10 post flight, the flight embryos exhibited liver induration through narrowing of sinusoids lumen. Haemopoietic zones became less numerous. By the end of embryonic development these histological differences of the flight and control liver disappeared essentially. Organogenesis and histogenesis of the liver obtained from the hatchlings that had spent 5 days in microgravity did not depart from the norm. However, inability of the birds to adapt to microgravity and ensuing starvation was the reason for dystrophic changes in the liver, venous congestion and increased histoleucocytic activity. All the liver changes faded away soon alter the hatchlings were settled in favorable life conditions

The paper reports the results of organogenic and histogenic investigations of the visceral organs of embryonic Japanese quails incubated in the microgravity aboard orbital complex Mir. Investigations of the gastrointestinal tract failed to reveal macrodeviations in the organs' structure, differentiation of layers or cells along the full length of the entodermal canal. However, comparison with the ground controls exhibited poor development of stromal connective tissues in the flight embryos evidencing loose arrangement and small number of fibers. Local hyperplasia in the duodenal epithelium was due to the proliferation rather than differentiation processes; it could affect food intake and parietal digestion in the flight chicks. Though the Japanese quail embryos developed in space microgravity had some deviations, their digestic apparatus was mature to uptake and assimilate food.

Pressurized low-sized module Kontur with an independent life support system (LSS) was developed by the Institute of Biomedical Problems cooperatively with the Special Design Bureau of Experimental Equipment to house gerbils (Meriones unguiculatus) aboard robotic technology-purpose spacecraft. Design of the module precludes pollution of the environment The fully equipped module weighs 69 kg; average daily power consumption is 62 watts. The environmental parameters for 12 animals flown on Foton-M3 in the period of September 14-26, 2007 were controlled within the following ranges: pO2 - 143-156 mm Hg, (mean 150 mm Hg), pCO2 - 0.76 mm Hg maximum (mean 0.64 mm Hg), temperature - 23-28 degrees C (mean 26.7 degrees C), relative humidity - 29% and 57% at the beginning and end of the flight, respectively (mean 39%). The animals consumed the palletized food prepared of natural products with a moisture content of approx. 20%. The day-night periods were 12 hrs. long. The daytime video recording of the animals went on continuously in the throughout the flight. The experiment showed that the module meets the requirements of experiments with mammals aboard returnable robotic spacecraft and piloted space stations. At the moment, the model is being redesigned for a 30-day BION-M1 mission.