Embryonic Mortality Research Articles

Effect of incubation temperature on sex-dependent embryo mortality and morphological traits in Mallard.

Although birds have genetically determined sex, the sex ratio has been reported to deviate from parity in several studies. Temperature-dependent sex determination, which is common in reptiles, is absent in birds. However, females are able to adjust their investment into eggs according to the sex of the embryo, which may cause sex-specific embryonic mortality. Incubation temperature may also cause sex-biased embryonic mortality, and it may differentially affect the phenotype of male and female hatchlings. We aimed to investigate differences between male and female Mallard embryos regarding their egg size, mortality during incubation and hatchling phenotype in relation to incubation temperature. Mallard eggs were incubated under six constant incubation temperatures (ranging from 35.0 to 38.0 °C). Hatchlings were weighed, and their morphological traits were measured. We determined the sex of hatchlings and unhatched embryos by genetic analysis and found higher male embryonic mortality at 35.5 °C (44 males vs. 28 females) and a higher proportion of female hatchlings at 38 °C (24 males vs. 38 females); however, these results were not statistically significant. Our results suggest that Mallard females do not differentiate quantitatively between sexes during egg production. Male hatchlings were significantly larger but not heavier than females. The size difference between sexes was most pronounced at temperatures around 36 °C, which is the mean temperature of naturally incubated Mallard eggs.

A missense mutation (p.Tyr452Cys) in the CAD gene compromises reproductive success in French Normande cattle

We scanned the genome of 77,815 Normande cattle with different Illumina SNP chips (Illumina Inc., San Diego, CA) to map recessive embryonic lethal mutations using homozygous haplotype deficiency. We detected 2 novel haplotypes on chromosomes 11 and 24 but did not confirm 6 previously reported haplotypes. The one on chromosome 11 showed a marked reduction in conception rates and moderate decrease in nonreturn rate in at-risk versus control mating, supporting late embryonic mortality. After fine mapping and analyzing whole-genome sequences, we prioritized a missense mutation in CAD (g.72399397T>C; p.Tyr452Cys)-a gene encoding a protein (carbamoyl-phosphate synthetase 2, aspartate transcarbamylase, and dihydroorotase) essential for de novo pyrimidine biosynthesis-as a candidate causal variant. This transition mutation replaces a tyrosine residue, which is perfectly conserved among living organisms, with a cysteine residue in the carbamoyl-phosphate synthetase 2 domain of the protein. A single animal was confirmed to be homozygous for the mutation based on Sanger sequencing. However, large-scale genotyping of the candidate variant with the Illumina EuroG10k BeadChip revealed an absence of live homozygotes in a panel of 33,323 Normande animals and an absence of carriers in 348,593 animals from 19 other cattle breeds. These results support recessive embryonic lethality with nearly complete penetrance, as was previously reported in CAD mutants in several eukaryote species. The only homozygous cow had extremely poor udder conformation, suggesting a potential role of CAD in udder development, but no effect was detected when comparing daughter yield deviations of 250 heterozygous bulls with that of 2,912 homozygotes for the ancestral allele. Together, our results showed the importance of large-scale screening for homozygous haplotype deficiency with hundreds of thousands of animals, validating results with an independent data set, and considering unexpected live homozygotes, to avoid both false-positive and false-negative discoveries. These discoveries will be used primarily in mating decisions to avoid at-risk mating. In addition, we recommend including CAD in the breeding objectives of Normande cattle.

Microclimatic effects on the incubation success, hatchling morphology and locomotor performance of marine turtles

Global atmospheric temperatures are predicted to rapidly increase within the next hundred years, consequently altering the microclimates of the sand dune environment where marine turtles lay their eggs. High nest temperatures can increase embryonic mortality, decrease hatchling vigour and size (i.e. quality), and also feminises the sex-ratio of clutches. Sand composition, vegetation cover, rainfall and sun exposure affect the temperature of sand surrounding a nest, however the effect of this variability in the beach environment on the incubation success of a sea turtle clutch is still relatively unknown. We conducted a manipulative study on loggerhead turtle nests at Mon Repos, Queensland, Australia, to investigate the effect of ground-cover vegetation vs bare sand and tree-shade vs no shade on incubation success, hatchling morphology and hatchling locomotor performance. Twenty-four nests were used in a two-factor experimental design, with tree-shade/sun and, ground-cover vegetated/cleared as fixed factors. Sun-exposed nests experienced higher nest temperatures (∼2 °C warmer), shorter incubation periods and poorer incubation success than those in tree-shade. Ground-cover-vegetated nests in tree-shade had lower hatching and emergence success (73%, 66% respectively) than sun-exposed nests placed in sites cleared of ground-cover vegetation (79%, 83% respectively). Hatchlings that emerged from cooler, tree-shaded nests were also larger and crawled faster than hatchlings from sun-exposed nests. We suggest for conservation projects on naturally ‘hot’ beaches, active management strategies such as selective groundcover vegetation removal and increased shading could be implemented to increase high quality hatchling production.

SUCCESS OF PROTOCOLS FOR SYNCHRONIZATION OF ESTRUS AND OVULATION IN DAIRY COWS IN SUMMER

Cattle farming, as one of the most important branches of livestock production, has longbeen confronted with the chronic problem of the decline in reproductive performances. In 2005, thenumber of cattle around the world amounted to about 1,370,000,000 heads of cattle, while in 2012this number was just over a billion, which indicates the importance of applying differentreproductive protocols in order to increase production. Heat stress leads to disorders of thephysiological and reproductive processes, as the rise in body temperature caused by heat stress hasdirect negative consequences on numerous cell functions. The study included a total of 54 Holstein-Friesian cows, 28 experimental and 26 control cows from PD Butmir farm with 5 lactations onaverage. Hormone protocols for estrus and ovulation were used in June and July 2013. Cows in theexperimental group were subjected to a Presynch + 5dCoS2 protocol. Cows that did not conceiveafter this protocol were immediately subjected to resynchronization with Cosynch -72 protocol. Thesuccess rate of the Presynch + 5dCoS2 protocol was 19%, while in the case of Cosynch 72 it was33%, which was statistically significant (p <0,05). The first presynchronization and synchronizationprotocol (5dCoS2) did not significantly help to improve the conception rate after the firstinsemination postpartum, but it is evident that they had a positive effect on another protocol (COS72)in the form of reduction in embryonic mortality in the summer months when embryonic loss is thegreatest.The COS72 protocol provides satisfactory results in the summer, but good fitness and healthmanagement, as well as heat stress reduction in accordance with the location and farm design arethe preconditions for a successful estrus and ovulation synchronization program prior to artificialinsemination.

Effects of high light intensity on egg weight loss, hatchability, embryonic mortality, and supply organ weight at hatch in quail hatching eggs during incubation

The aim of this study is to investigate the effects of high light intensity on egg weight loss, hatchability, embryonic mortality, and supply organ weights at hatch in Japanese quail ( Coturnix coturnix japonica ) eggs. A total of 640 hatching eggs were randomly distributed into 2 groups. The first group of eggs were continuously incubated in the dark (Control; C), the second group of eggs were incubated in continuous light(L), the third group of eggs were incubated in the dark for the first five days of incubation (D5), and the last group were incubated in the light for the first five days in the eggs (L5). The light intensity at the surface of the eggshell varied from 5000 to 6000 lux as measured with a luxmeter. No significant differences were found in egg weight loss, hatchability, and supply organ weight among treatments. Embryonic mortality were higher in the L5 group than in the control group at 10 to 16 days of incubation. These results demonstrate that high light application during incubation affected the embryonic mortality negatively except hatchability and egg weight loss.

Comparative evaluation of two methods of pregnancy diagnosis in dairy cattle in the East of Algeria: proteins associated with pregnancy and ultrasonography

ABSTRACT An early and reliable diagnosis of pregnancy in cows is of considerable economic interest. It would improve the profitability of farmers by reducing the calving-calving interval and avoid any delay of fertilisation which is a cause of significant economic losses. The aim of this study is to evaluate and compare two diagnostic methods of pregnancy in cows after artificial insemination by the assay of the pregnancy-associated proteins (PAGs) and the ultrasonography. The study was carried out on 41 cows aged 3 to 6 years from the Batna region. Blood samples were collected at day (D28) post insemination. This study has shown that among the 41 cows, 25 (60.98%) were pregnant and 16 (39.02%) were not using the transrectal ultrasonography. The sensitivity and the specificity of the PAG assay were 100% and 93.75%, respectively. The specificity was 100% for the ultrasonography, and the embryonic mortalities was 2.43%. The comparative study of the two diagnostic methods of pregnancy has revealed the liability and precocity of the biochemical methods. It is necessary to sensitise inseminators and farmers to the importance of early diagnosis of pregnancy, especially by the use of PAG’s assay. It is an essential component of reproduction monitoring and an excellent indicator of early abortions.

Effect of including n-3/ n-6 fatty acid feed sources in diet on fertility and hatchability of broiler breeders and post-hatch performance and carcass parameters of progeny.

ObjectiveThe present trial was conducted to determine the influence of different dietary fatty acid (omega-3 and omega-6) sources on reproductive performance of female broiler breeders and growth performance and carcass traits of their progeny.MethodsTwo hundred and twenty, 25 weeks old Ross-308 male (20) and female (200) broiler breeders were used in the experiment for the period of 6 weeks. All birds were randomly divided into four dietary treatments (containing 2% soybean oil, 2% sunflower oil, 2% flaxseed oil, and 2% fish oil) each with five replicates of one male and ten females. Throughout this experiment hatching performance of broiler breeders, progeny growth performance and carcass parameters were recorded.ResultsThe results showed that the inclusion of different fatty acid sources in female broiler breeders diet had no significant effects (p>0.05) on number of fertile eggs, post-hatch mortality, and fertility rate. The soybean oil supplemented group had significantly (p<0.05) higher late embryonic mortality compared to other three treatments.ConclusionIt was concluded that inclusion of 2% of different sources of omega-3 and omega-6 fatty acids (especially 2% flax seed oil) in broiler breeders’ diet can reduce late embryonic mortality. The other reproductive characteristics of parents and growth and carcass characteristics of progeny remained unaltered by dietary sources of omega-3 and omega-6 fatty acids.

Graphene oxide induces cardiovascular defects in developing zebrafish (Danio rerio) embryo model: In-vivo toxicity assessment

Graphene oxide (GO) has wide engineering applications in various areas, including electronics, energy storage, pharmaceuticals, nanomedicine, environmental remediation and biotechnology, because of its unique physico-chemical properties. In the present study, the risk-related information of GO was evaluated to examine the potential ecological and health risks of developmental toxicity. Although the overall developmental toxicity of GO has been well characterized in zebrafish, however, its release effect at a certain concentration of living organisms with specific cardiovascular defects remains largely elusive. Therefore, this study was conducted to further evaluate the toxicity of GO on embryonic development and cardiovascular defects in zebrafish embryos used as an in-vivo animal model. As a result, the presence of GO at a small concentration (0.1–0.3 mg/mL) does not affect the embryonic development. However, GO at higher concentrations (0.4–1 mg/mL) induces significant embryonic mortality, increase heartbeat, delayed hatching, cardiotoxicity, cardiovascular defects, retardation of cardiac looping, increased apoptosis and decreased hemoglobinization. These results provide valuable information that can be used to study the eco-toxicological effects of GO for assessing its bio-safety according to environmental concentration. In addition, the present results would also be usefully utilized for understanding the environmental risks associated with GO on human health in general.

Reproduction in female South American domestic camelids

Alpacas and llamas are induced ovulators. They show marked reproductive seasonality in the Andean region, but under Northern Hemisphere conditions of feeding and management, they are non-seasonal breeders. Puberty is attained when they reach 50% of adult body weight. When they are not exposed to a male, females show successive waves of follicular maturation and atresia. Growth, maintenance and regression of a follicle each require an average of 4 and 6 days in alpacas and llamas, respectively. After sterile mating, progesterone concentrations in blood were increased from day 5, reached maximum concentrations on day 7-8, and declined rapidly at 9-10 days after mating. A fertile mating results in formation of a corpus luteum that remains functional throughout gestation. The duration of gestation is 340-346 days. Almost all fetuses were found to occupy the left uterine horn, even though ovulation occurs from both ovaries with equal frequency. Several methods of pregnancy diagnosis have been described. Mating is recommended within 15-20 days after parturition to obtain good fertility rates and one offspring per year. The factors that contribute to high rates of embryonic mortality are unknown. Reproductive technologies, such as AI, superovulation, embryo transfer and IVF, have not been used very extensively in these species but can be successfully applied.

Enhancing reproductive performance in domestic dairy water buffalo (Bubalus bubalis)

The purpose of the review is to describe the factors that affect fertility in domestic water buffalo (Bubalus bubalis) and the techniques that enable an improvement in reproductive performance. On Italian and Latin American farms where natural mating is practiced and bulls are always present in the herd, the inter-calving interval is approximately 400 days and the culling rate is lower than 15%. The buffalo has a tendency for seasonal reproductive activity. Reproduction is favoured when there is a decrease in day length. Ovarian activity stops if conception does not occur within 3 to 5 ovarian cycles. It is important, therefore, that appropriate management of the transition period is practiced, particularly with respect to the hygienic conditions of the uterus. In tropical countries located north of the equator, feed deficiencies and heat stress are considered the main factors that lead to poor fertility in the summer. In Pakistan, for example, the increase in body condition score during the autumn was associated with the commencement of the breeding season in buffaloes. Anoestrus is observed also in Italy, however, where the average daily temperature during the same period is 13.5 to 23.5 degrees C and feeding is constant throughout the year. The only common element between the two areas is the progressive increase in daylight hours between April and June and the day length greater than 12 hours up to September. In Italian herds that apply an out-of-season breeding strategy, an improvement in fertility (measured as the percentage of corpora lutea corresponding to subsequent pregnancy) is observed when water pools are present on the farm. This demonstrates that an improvement in environmental conditions reduces the incidence of embryonic mortality and/or abnormal cycles. To summarize, in the absence of serious nutritional problems, an improvement in environmental conditions increases fertility in buffalo.

Kars İli Yetiştirici Koşullarındaki Kazların (Anser anser) Yumurta Verimi, Kuluçka, Büyüme, Kesim ve Karkas Özellikleri (I. Yumurta Verimi ve Kuluçka Özellikleri)

In order to determine egg production, yield records of 200 mature geese were used from 60 family enterprises. Total 2365 eggs were examined in order to determine the traits of egg yield. While examining mature geese to determine egg production and its traits, geese were grouped according to their feather color (white, yellow, black, piebald, and grey) and ages (1, 2, 3, 4, and &gt;4). In determining the hatchability characteristics, age, feather color and egg weight (170.00). The general means of egg production and egg laying period was 12.66 ± 0.07 per geese and 28.61 ± 0.19 per day respectively, While the general means egg weight and egg shape index values were 163.74 ± 0.38 g and 65.78% respectively. The effect of age and feather color groups on egg production and laying period were significant. The general mean of natural hatchability traits of the geese eggs such as fertility rate, hatchability rate, hatching rate, embryonic mortality rate, and mortality in shell rate were found 76.10%, 60.88%, 80.00%, 13.16% and 6.84% respectively. While the effect of feather color on the natural hatching traits was insignificant, the effect of maternal age on fertility rate was significant but the effect on the other properties examined was insignificant. As a result, the egg production and laying period of Turkish domestic geese were lower than those of many goose breeds but egg weight was similar to many goose breeds. It was determined that hatching yield increased as egg weight increased. In terms of egg yield, it was determined that 3-year-old geese were higher than other age geese.

Influence of the egg classification process on productivity indexes of an industrial hatchery

The present work has the objective of evaluating the viability of the process of transfer or not of the eggs in the farm on the effects in the artificial incubation. To evaluate this practice, the productivity indexes of 3,072 eggs were studied, divided into two categories: classified and unclassified eggs. Fertility, hatchability, embryonic mortality and contamination rates were determined. The hatchability and fertility indexes in relation to the total number of eggs were influenced in relation to the classification process (p

Using wave runup modeling to inform coastal species management: An example application for sea turtle nest relocation

The inundation of foreshore and backshore coastal environments caused by wave runup or groundwater intrusion can be extremely detrimental for beach-dwelling organisms. For beach-nesting species, whose eggs require sufficient gas exchange with the surrounding environment for proper embryonic development, inundation for prolonged periods can result in embryonic mortality. Management strategies such as the relocation of nests high on the beach to avoid wave action have been applied for some species, though this strategy may result in unnecessary nest manipulation. To improve the identification of beach locations potentially exposed to inundation caused by wave wash-over which may require management action, wave runup models were tested in Fort Morgan, Alabama, USA for the 2016 sea turtle nesting season. The potential exposure of sea turtle nesting sites to wave wash-over was determined by comparing observed nest elevations to the predicted combined elevation of wave runup, tide, and surge (i.e., total water level). Total water level was calculated using three different definitions of beach slope: foreshore, nest, and dune-to-water (DTW), and two LiDAR-derived elevation estimates: the most recent survey from 2016 and a time-averaged digital elevation model (DEM). Models using the time-averaged DEM performed as well as, or better than, those using the 2016 LiDAR survey in the majority of comparisons. Wash-over state was correctly identified for up to 83.3% of sites when using nest slope in the wave runup calculation. However, DTW slope performed the best when predicting the wash-over frequency of a site. Mapping of the predicted 98th percentile of wave runup indicated that only 11.2% of nesting sites were exposed to wave wash-over, in contrast to the 21.3% of nests which were relocated. Wave runup models have not previously been used to inform sea turtle conservation actions; however, it holds promise for improved targeted management interventions and can assist other species (e.g., shorebirds, beach mice), which rely on dry beach habitat for nesting, feeding, and migratory rest stops. Wave runup models can also be used to investigate past storm events, forecast approaching storm impacts, and supplement sea level rise scenarios for coastal species management at multiple spatial scales.

Effect of sex ratio, storage time and temperature on hatching rate, fertility and embryonic mortality in Chukar partridge (Alectoris chukar)

Chukar partridges (Alectoris chukar) are frequently reared in captivity with the aim of producing fertile eggs and chicks. The aims of the present study were to evaluate the effect of male to female sex ratio on hatching rate and fertility and to determine the optimal temperature and time for egg storage and its effect on hatching rate and embryonic mortality in Chukar partridges. Maximum hatching rate and fertility rate were affected by male:female ratios during breeding (P < 0.05). The greatest embryonic mortality rate was with eggs that were stored at 25 °C for 15–20 d, however, the greatest hatching rate was when eggs were stored at 10 and 15 °C for 5 days. Storage time of Chukar partridge eggs can be extended for as long as 5 d, but longer storage periods can negatively affect hatching rate. In conclusion, a reduction of storage temperature and duration of time of storage in combination with reducing the sex ratio of the egg producing females and males during the breeding period might improve fertility, hatching rate and fertility of Chukar partridge eggs.

Low-mobility sperm phenotype in the domestic turkey: Impact on sperm morphometry and early embryonic death.

The sperm mobility assay measures the ability of sperm to swim through a dense layer of Accudenz® , and the sperm mobility phenotype has been shown to predict fertility and other sperm performance traits in roosters and turkeys. In this study, we examined turkey sperm morphometry and rates of early embryonic death associated with high- and low-mobility semen. We also assessed whether the hypo-osmotic stress test, which evaluates the structural integrity of the sperm plasma membrane, may be used as a faster and simpler assay for sperm mobility and viability. We confirmed previous work that found that high-mobility sperm are faster and swim more linearly than low-mobility sperm, and that mobility traits were repeatable within males. In contrast to previous studies, we did not find higher rates of fertility, but low-mobility sperm was associated with higher rates of early embryonic death, though this trend was not significant. High-mobility sperm had longer sperm heads, explained by longer nuclei, despite shorter acrosomes. Although these sperm were faster, midpiece length and flagellum length did not differ between high- and low-mobility sperm. Finally, mobility was not found to be associated with sperm performance in the hypo-osmotic stress test.

The effect of increased concentration of carbon dioxide during the first 3 days of incubation on albumen characteristics, embryonic mortality and hatchability of broiler hatching eggs1.

Three experiments were conducted to determine the effects of increased CO2 concentration during the first 3 d of incubation on albumen height and pH, embryonic mortality, and hatchability of broiler hatching eggs. Hatching eggs were obtained from commercial broiler breeder flocks of Ross 308 at 39 and 37 wk of age in Experiments 1 and 2, respectively. In Experiment 3, eggs were collected at 28 and 35 wk of age. Eggs were incubated under either standard conditions (Control-CO2) for the entire incubation or increased CO2 concentrations during the first 3 d of incubation (High-CO2) in 3 experiments. In Experiments 1 and 2, the CO2 concentration was gradually increased from the beginning of incubation onwards to reach 0.80% at 72h by manual injection of CO2 into airtight laboratory incubators. In the control incubators, the CO2 concentration remained below 0.10% during the same period. Prior to setting, and at 3 d of incubation, the eggs were opened for albumen height and pH measurements in Experiments 1 and 2. In Experiment 3, the eggs were set in commercial incubators. During the first 3 d of incubation, the CO2 concentration was gradually increased to reach 0.70% at 72h naturally (High-CO2). In the Control-CO2 incubator, the CO2 concentration remained below 0.10%. After 3 d, incubation was continued with the control incubator conditions for all eggs from both groups in the 3 experiments. The albumen height was not affected by CO2 treatment, but the treatment significantly decreased albumen pH at 3 d in Experiments 1 and 2 (P < 0.05). A greater CO2 concentration during early incubation reduced fertile hatchability due to increased early embryonic mortality by 2% in the 3 experiments (P ≤ 0.05). The differences in pH might provide one explanation why increased CO2 concentration during early incubation resulted in increased early embryonic mortality. These data indicated that at the beginning of the incubation, ventilation was necessary to prevent increases in CO2 concentration for optimum hatchability results.

EFFECT OF IN-OVO INJECTION OF TESTOSTERONE ON HATCHABILITY AND PLASMA CONSTITUENTS IN DOKKI-4 CHICKENS

This study was designed to evaluate the effects of testosterone propionate (TP) on hatchability, chick measurements and some plasma metabolites in Dokki- 4 strain of chickens during embryogenesis stage. A total of 350 fertile eggs (45-55 g. in average) were individually weighed and incubated .At the 5th day of incubation, eggs were divided into 3 experimental groups as follow; control(C) non-injected groups ,while the other groups T1 and T2 eggs were injected in albumin with 25 and 100µg TP solvated in 50µl plant oil. Results showed that hatchability % was significantly decreased in-ovo injected groups by 1214%than control groups, while embryonic mortality rate was increased by in-ovo injection with TP. Chick weight, total protein, albumin, calcium and phosphorus levels were significantly increased in TP injection than control .Also, male chicks % based on the visual examination was increased by TP in –ovo injection than control. In conclusion: in-ovo injection of TP at the 5th day of incubation with 25 and 100µg TP/50µl plant oil had decreased the hatchability %, but increased embryonic mortality, some plasma constituents, male% ,chick weight and chick length in Dokki-4 strain of chickens.

Are magnetic and electromagnetic fields of anthropogenic origin potential threats to early life stages of fish?

The number of underwater cables transferring electric current in sea and freshwater environments is constantly increasing. As a result, the risk of negative effects of magnetic fields generated in the vicinity of those cables on fish eggs and larvae is also growing. This is especially the case for species that settle on the bottom for certain periods of time during early development. To study those effects, eggs and larvae of rainbow trout, Oncorhynchus mykiss, were subjected under experimental conditions to a static magnetic field (MF) of 10 m T and a 50 Hz electromagnetic field (EMF) of 1 m T for a period of 36 days (i.e., from eyed egg stage to approximately 26 days post hatching, dph). Neither MF nor EMF had significant effect on embryonic or larval mortality, hatching time, larval growth, or the time of larvae swim-up from the bottom. However, both MF and EMF enhanced the yolk-sac absorption rate. Although it was not related directly to magnetic field effect, it was also shown that larvae with absorbed yolk-sacs by the time of swim-up were less efficient in taking advantage of available food at first feeding (i.e., obtained smaller weight at age). That indicates the importance of processes affecting yolk-sac absorption rate.

Maternal recognition of pregnancy in some domestic animals: A review

Introduction: Maternal Recognition of Pregnancy (MRP) is a physiological process whereby the conceptus signals its presence to the maternal organism and prolongs the lifespan of the corpus luteum. MRP is critical to homeostasis of pregnancy. Many cases of pregnancy losses have been attributed to the failure of MRP. One of such cases is early embryonic mortality, a leading cause of infertility in animals. The purpose of this review is to highlight the general mechanisms of MRP and the specie-specific differences in some domestic animals. Method: A search was conducted with the exploration and filtration of databases and repositories of Google Scholars, Scopus, PubMed and ResearchGate for scientific publications. Results: This article explains mechanisms of MRP in different domestic species of animals. Significance: The concept would provide a better insight in understanding a major aetiology to pregnancy losses, which has an implication on production and the agrarian economy.

Защита сперматогенеза β-каротином при радиационных воздействиях. Сообщение 2: обогащение каротиноидом рациона при однократном остром внешнем γ-облучении

Purpose: Experimental evaluation of the efficiency of β-carotene by single acute γ-irradiation of spermatogenesis correction radiation-induced disorders in males (♂) of Wistar rats during prolonged carotenoid enrichment of a diet. Material and methods: Single external gamma irradiation ♂ was performed at the IGUR facility (137Cs, dose rate 0.029 Gy/s). The carotenoid used up on feeding ♂ in a mixture with cottage cheese for 2 months before irradiation, then – throughout the study period three times a week. During the days that ♂ were in cells with intact ♀ β-carotene was administered ♂ orally by a probe in the form of a suspension in vegetable oil. The damage and effectiveness of protection of spermatogenesis of irradiated ♂ were judged by the state of their reproductive function. Results: β-carotene in intact ♂ rats reduced the overall, pre- and postimplantation embryonic mortality, respectively, from 29 to 14, from 22 to 9, and from 10 to 5 %. At the stage of mature sperm following irradiation ♂ dose of 3 Gy – total and pre-implantation mortality from 45 to 29, and from 23 to 9 %. After irradiation at a dose of 5 Gy – total, an pre- and postimplantation induced embryonic death, respectively, from 67 to 56, from 23 to 13 % and from 56 to 43 %. At the stage of spermatids after irradiation in dose 1 Gy – pre-implantation mortality from 23 to 9 %; in the dose of 3 Gy – the number of dead embryos in pregnant ♀ from 12 to 3; at a dose of 5 Gy total embryonic mortality from 57 to 49 %. Carotenoid enrichment of a diet of ♂ irradiated at doses of 3 and 5 Gy, has not corrective impact on the state indicators of their reproductive function, evaluated at fertilization of ♀ sperm irradiated at the stage of spermatocyte. At the stage of spermatogonia after irradiation at a dose of 3 Gy β-carotene increased fertility of ♂ 7 to 12 living embryos and reduced the overall, before – induced postimplantation mortality, respectively, with 63 and 43, from 42 to 25 and from 35 to 19 %. No statistically significant effect of β-carotene on the weight loss of the gonads irradiated ♂ was revealed. Compared to short-term regimen, long-term enrichment of a diet of irradiated ♂ β-carotene more effectively reduced embryonic mortality of their offspring. Conclusions: Correction effects of β-carotene enrichment of the diet in radiation-induced disturbances by single acute external γ-irradiation at doses of 3 and 5 Gy of spermatogenesis in Wistar rats at stages of mature spermatozoa, spermatids and spermatogonia have been established.