Effects of L-ascorbic acid and alpha-tocopherol on biochemical parameters of swimming-induced oxidative stress in serum of guinea pigs

Background: The purpose of this study is to determine the effect of L-ascorbic acid and alpha-tocopherol as well as combination of these vitamins with or without exposure to physical exercise on intensity of lipid peroxidation, activity of xanthine oxidase, activity of total antioxidative system, concentration of glutathione, and activity of catalase in the serum of guinea pigs.Materials and Methods: The experimental measurements of intensity of lipid peroxidation, activity of xanthine oxidase, activity of total antioxidative system, concentration of glutathione, and activity of catalase were done in the serum of guinea pigs. The animals were exposed to the test load to achieve exhaustion and the test was terminated when the animal for the third time to sink into the water.Results: The results of this study demonstrated that endurance exercise of guinea pigs induced oxidative stress response in terms of increased lipid peroxidation and activity of xanthine oxidase in the serum of experimental animals. Our study investigated the antioxidant activity of L-ascorbic acid and alpha-tocopherol also measuring three protective markers in the serum: total antioxidant activity, content of glutathione and activity of catalase. The results obtained show that the vitamins influence the concentrations of above mentioned biochemical parameters, which points out their protective effect of swimming-induced oxidative stress.Conclusion: Single or combined administration of L-ascorbic acid and alpha-tocopherol caused significant inhibition of these markers indicating the important antioxidant activity of the vitamins. Results lead to conclude that the combined treatments with vitamins with or without exposure to physical exercise showed the clear synergistic effect.Key words: L-ascorbic acid, alpha-tocopherol, guinea pigs, oxidative stress,  biochemical parameter

Rational use of hormones in dairy cows reproduction

Хормони и антибиотици су најчешће коришћени лекови у репродукцији животиња. У поређењу са другим терапијским индикацијама, хормони се више користе него антибиотици у лечењу репродуктивних поремећаја. Оболеле животиње треба лечити како са становишта добробити животиња, тако и због одржавања и унапређења њихових производних резултата. Успех у репродукцији мери се врло прецизним параметрима ефикасности производње као што су индекс осемењавања, дужина сервис периода, међутелидбено раздобље, репродуктивни ремонт запата. Примена хормона захтева рационалан приступ који подразумева постављање прецизне дијагнозе и у складу са тим и избора терапијског протокола. Најчешће индикације за примену хормона односе се на протоколе синхронизације еструса и овулације, лечење патолошких стања репродуктивних органа (цисте на јајницима, ендометритиси, пиометра, итд) за индуцију порођаја или побачаја, односно као потпорна терапија у лечењу маститиса. Успешност примењене терапије не зависи искључиво од избора хормонског протокола, већ и од општег здравственог статуса краве, њене кондиције, метаболичког статуса, исхране али и амбијеталних услова (топлотни стрес, доступност хране и воде, зоохигијенски услови). Хормонски протоколи који имају за циљ фиксирање времена осемењавања и последично смањења манипулативних трошкова и ангажовање људства, врло су осетљиви на пропусте у менаџменту. У репродукцији крава најчешће примењивани хормони су простагландини, гонадотропни рилизинг хормон и његови изомери, синтетски хипофизарни и екстрахипофизарни гонадотропини, прогестеронски интравагинални апарати и окситоцин. Сви наведени хормони су безбедни за примену код млечних крава јер не остављају резидуе у млеку.Hormones and antibiotics are the most commonly used drugs in animal reproduction. Compared to other therapeutic indications, hormones are used more than antibiotics in the treatment of reproductive disorders. Diseased animals should be treated both from the point of view of animal welfare and to maintain and improve their production results. Success in reproduction is measured by very precise parameters of production efficiency, such as the insemination index, the length of the service period, the intercalving period, and the reproductive overhaul of the herd. The use of hormones requires a rational approach, which implies the establishment of a precise diagnosis and, accordingly, the selection of a therapeutic protocol. The most common indications for the use of hormones refer to estrus and ovulation synchronization protocols, the treatment of pathological conditions of the reproductive organs (ovarian cysts, endometritis, pyometra, etc.) for the induction of childbirth or abortion, that is, as supportive therapy in the treatment of mastitis. The success of the applied therapy does not depend exclusively on the choice of hormonal protocol, but also on the general health status of the cow, its condition, metabolic status, nutrition, and environmental conditions (heat stress, availability of food and water, animal hygiene conditions). Hormonal protocols, which aim to fix the time of insemination and consequently reduce manipulative costs and human resources, are very sensitive to management failures. In cow reproduction, the most commonly used hormones are prostaglandins, gonadotropic releasing hormone and its isomers, synthetic pituitary and extrahypophyseal gonadotropins, progesterone intravaginal devices and oxytocin. All the mentioned hormones are safe for use in dairy cows because they do not leave residues in the milk.Zbornik radova i kratkih sadržaj

Assessment of Geotourism Values and Ecological Status of Mines in Kopaonik Mountain (Serbia)

Abandoned mines can pose a major environmental hazard. At the beginning of the 21st century, significant steps were taken all around the world in order to protect these historically valuable complexes, and the mining heritage was recognized as a potential for the development of alternative tourism. This exploration covers mines in the Kopaonik Mountain area. Mining on this mountain began in ancient times. It has developed throughout history, and today only one mine is active. Three abandoned (Gvozdac, Suvo Rudište and Raičeva Gora) and one active mine (Belo Brdo-Zaplanina) are the subject of research. The basic aim of the research is twofold. The estimation of geo-tourist values was performed using the Geosite Assessment Model (GAM), and the ecological status assessment WAS performed according to the standard model based on negative and positive values. Based on the applied methods, it was concluded that mines (geosites) have a high level of natural characteristics, and that differences between geosites are evident in tourist values. The reason for this is insufficient tourist affirmation and the insufficient availability of tourist infrastructure. With the ecological status, positive values were observed on the geosites, which also differ from one (Raičeva Gora) to 15 points (Gvozdac). In the end, the results obtained are of great scientific importance, and their direct application is in the development of the Tourism Development Strategy in the Kopaonik area