Regulation of the Duration of Spawning Cycles of Catfish in Industrial Aquaculture

This article is devoted to the study of the qualitative and quantitative characteristics of the African Catfish Clarias gariepinus eggs produced at different durations of the inter-spawning interval. Eggs were produced artificially using sex hormones. In industrial aquaculture, the African Catfish Clarias gariepinus does not reproduce naturally. Therefore, the problem of obtaining high-quality eggs that will be used for in-vitro fertilization is urgent. To implement artificial spawning of fish in industrial aquaculture, it is necessary to correctly choose the effective hormonal stimulator and empirically select its dose. Sex hormones are involved in regulating the duration of the inter-spawning interval and affect the quality of eggs produced both for fertilization and for food purposes. The pituitary gland of the African Catfish Clarias gariepinus and surfagon were used as gametogenesis stimulators. The aim of the work was to study the optimal duration of the inter-spawning interval and the effect of hormonal inducers used to stimulate artificial spawning in industrial aquaculture. The use of the catfish pituitary gland in fresh or acetonated form as a hormonal stimulator provided higher-quality eggs, compared to the synthetic hormonal drug - surfagon. Stimulation with acetonated pituitary injections reduced the inter-spawning interval of the African Catfish Clarias gariepinus to three months, and the use of surfagon prolonged the inter-spawning interval to four months. Reducing the duration of the inter-spawning interval is important for the production of the African Catfish Clarias gariepinus eggs for food purposes. Studies have shown that reducing the optimal duration of the inter-spawning interval negatively affects the quality of the produced eggs and their quantity. This research was financially supported by a grant from the Russian Foundation for Fundamental Research, project No. 18-016-00127. Keywords: aquaculture, African Catfish Clarias gariepinus, eggs, inter-spawning period, sex hormones, oocyte

Arachnoentomoses of domestic carnivores and effectiveness of insacar total in dogs otodectosis

The research analyzes the epizootological features of arachnomyioses of domestic carnivores of different species on the territory of cities in the Middle Volga region. With varying degrees of extensive invasion, this group of diseases consisted of sarcoptic mange of dogs, ear mange of dogs and cats, demodecosis of dogs, notoedric mange of cats and aphanipterosis of animals. The authors studied the seasonal, age and breed dynamics of sarcoptic mange of dogs, notoedric mange of cats, demodectic mange of dogs and aphanipterosis of cats. The authors established the peaks of invasion in arachnomyioses of various species of domestic carnivores, identified the most vulnerable age groups of animals to diseases. The analysis of the breed predisposition of animals to this group of diseases and the distribution of sick animals by sex was carried out. It is established that arachnomyioses are characterized by regional epizootological features. A new drug Insakar Total C, developed by the staff of FGBNU FNC VIEV RAS (Moscow) for ear mange of dogs, was tested. The research was carried out on dogs of the shelter for homeless animals "Paw of Help" at the Ulyanovsk SAU. During the test, it was found that Insakar Total C shows 100% therapeutic effectiveness in ear mange of dogs of moderate severity. The use of the drug, according to the instructions and instructions, completely frees sick animals from ticks- ear mange. The research was carried out with the grant support of the Ministry of Agriculture of the Russian Federation

ASSESSING EFFICIENCY OF THE CONIFEROUS ENERGY SUPPLEMENT IN THE DIET OF DAIRY COWS FOR MAINTAINING PRODUCTIVE HEALTH

  Objective: This study was aimed at assessing efficiency of the original coniferous energy supplement in the diet of cows at the end of the dry period - beginning of lactation - for improving the energy density of diets, enriching them with vitamins and major and minor nutrient elements, improving milk productivity, and maintaining productive health.Methods: The scientific-production experiment was performed on the basis of the Lukoshkino†unit of the Klenovo-Chegodaevo†research farm (Moscow) on twenty cows. The preparation was fed at the rate of 150 g for 20 days before calving and for 30 days after calving.Results: Studies have found the positive effect of the preparation on the average daily milk yield, natural fat content increased by 5.4%-6.9% (with butterfat percentage increased by 0.09%), and reduced cost of feed per unit of obtained product.Conclusion: The use of the preparation promoted enzymatic processes in the rumen, had positive effect on the carbohydrate-lipid and protein metabolism, and had no negative effect on the non-specific resistance of cows

Influence of luminance modeses on the metamorphosis of artemia in aquaculture

The article presents the results of studies of the influence of luminance modes on ontogenesis of artemia cultivated in artificial conditions in a closed cycle. The aim of the work was to study the effect of light on morphological features of artemia at different stages of ontogenesis. During the work, the luminance modes of 1.5 kl, 2.5 kl and 4 kl were used. It was found that the intensity of the light flux differently affects the ontogenesis and development of individual parts of the body of artemia. In one case, during the cultivation of artemia, optimal results were obtained at 2.5 klx, in the other at 4 klx. The luminance mode of 1.5 klx, turned out to be the least effective. Observations of the growth and development of Artemis larvae in an artificial environment revealed that the luminance mode of 4 klx had a more noticeable stimulating effect on the length of the body, abdomen, cephalothorax and furca than the mode of 2.5 klx at the initial stages of postembryonic development of larvae during the first 120 hours. When cultivating sexually mature artemia, as the results of studies have shown, the luminance mode - 2.5 klx had a more pronounced effect on body length, abdominal length, cephalothorax length, abdominal width and the number of bristles on the furc than the 4klx mode. For the first time, the results of morphological studies demonstrating the effect of light intensity on the development of individual parts of the body of crustaceans in aquaculture have been obtained. The study was supported by the Development Program of the Saratov state university of genetics, biotechnology and engineering named after N.I. Vavilov (Prioritet -2030)

Functional biologically active feed additive for breeding stock of fish

The work is devoted to the development and evaluation of the complex effect of a biologically active feed additive that meets the requirements of a functional feeding complex that ensures the regulation of physiological processes in the body of female breeding stock. In particular, influence of feed additives and its components on growth rate, quality of sexual products, reproductive process, embryogenesis, level of anomalies in the development of offspring, its growth potential was studied. The biologically active feed additive for the breeding stock included probiotic «Sporotermin», adaptogen «Trekrezan», vitamin-amino acid complex «Chiktonik». The hypothesis was tested that the developed feed additive, due to the peculiarities of its composition, is able to increase the growth rate of fish, optimize gametogenesis, reduce the level of pathology during embryonic development, increase the yield of larvae, increase their viability, reduce the level of developmental anomalies, increase survival and safety. The research results showed that the biologically active feed additive reduced the time of fish rearing, had a positive effect on the quality of female eggs and sperm in males, increased the quality characteristics of eggs, reduced the level of embryonic death during embryo incubation, increased the yield of larvae and their safety

Features of artemia salina ontogenesis in aquaculture depending on the salt level

The work is devoted to the study of influence of salinity level at the rate of hatching, productivity and morphometric parameters of artemia in aquaculture. The cultivation technology of Artemia salina in aquaculture for obtaining live starter feeds has been used in practice for a long time, but it is still far from perfect, since it is developed for a certain averaged artemia, and in practice we have to deal with specific species and their ecomorphs (ecological morphotypes), the optimal conditions of cultivation of which differ in many ways. One of the most important factors determining the development of artemia is the salinity of the environment. The aim of our study was to assess the effect of the salinity level of culture medium at the rate of hatching, productivity and morphometric parameters of artemia grown in industrial aquaculture. The results of the study showed that with an increase in the concentration of salt in the solution for cultivation of artemia, metamorphosis of the free embryo in nauplia is prolonged and the percentage of their yield decreases. Differences in the average population indicators of length and body weight of nauplia were found, which tended to decrease with an increase in water salt concentration. When studying the absolute fertility of female artemia grown at different concentrations of salt, it was found that an increase in water salinity in reproductive age of females makes it possible to increase their absolute fertility when breeding in artificial conditions

Corrective effect of probiotics on the work of the fish body in industrial aquaculture

Abstract. The world community associates the solution of the problem of food security with the development of aquaculture. The search for means of intensifying the production of a complete and easily digestible food protein in aquaculture is an important and urgent problem. Recently, probiotics, which have long been in demand in medicine, have been used in aquaculture to improve health, accelerate growth and improve the quality of fish in aquaculture. However, the correct choice of a probiotic for aquaculture is not an easy task, since in the modern world a wide range of probiotic preparations is produced in various forms, the dosage of which for aquaculture needs has not been developed, as well as the dosage and duration of their use have not been developed. Meanwhile, the use of probiotics in aquaculture can be expected to increase the production of marketable fish of improved quality. Probiotics for aquaculture should be resistant to gastric juice, able to colonize the intestines of fish, interact with the normobiota of the intestine and suppress pathogens. These properties are possessed by the probiotic "Sporotermin". It consists of freeze-dried spores of the bacteria Bacillus subtilis and Bacillus licheniformis. The content of viable spores in the preparation is not less than 3x10/9 CFU/g. The research results showed that the use of the probiotic "Sportermin" in aquaculture has a healing effect on fish, normalizes the structure of intestinal and liver tissues, affects the leukogram, activates the immune response system, reduces the level of oxidative stress, activating antioxidant defense enzymes and reducing the level of malondialdehyde. The research was carried out on the instructions of the Ministry of Agriculture of the Russian Federation