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چکیده
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Aging represents the sum of biological changes, organ wear, and decreased cellular regenerationcapacity. moreover, the metabolic rate drops, metabolic disorders start to develop, and thefunctionality of the immune system is diminished, which triggers the production of antibodiesthat destroy the body's own tissues. although the changes accompanying the aging process aredefined, its course in individuals is very idiosyncratic and unpredictable, being determined bynumerous interactions between environmental factors and living organism.geriatric horsethe modern human being strives to achieve longevity and maintain the best health status possible;moreover, they now extend these goals to their companion animals such as horses.the age atwhich an animal is classified as old can be defined in various ways,including physiological orfunctional age and chronological age. physiological age can differ between horses and dependson their genetic, use, and environmental conditions. despite great knowledge of veterinarymedicine, it is not possible to unequivocally determine when a horse reaches full maturity andwhen it getting old. this is because of the fact that aging is a continuous and time-spanningprocess, yet it is conditioned by the environment, including the breed of the animal species.the concept of “mature” is commonly used to describe animals that have fully completed theirphysical and mental development. horses aged older than 5 years of age considered fullyphysically mature. based on scientific research, 5-year-olds of all breeds have a fully builtskeleton, the basic muscle groups, and dentition, and they maintain balance while inmotion.unfortunately, at that time they are not at all experienced as working animals, mainlybecause of their emotional immaturity and lack of training. over time, the horse gains experienceand develops its predispositions, for example, by training and contact with humans and newsurroundings, but this sometimes takes many years.nevertheless, the term “mature” is commonly used to describe horses aged 5-15 years. horsesaged 15 years and older are called “geriatric” by some researchers; however, some others use theterm “geriatric” or “aged” for horses that have crossed the age of 16 years or even 20 years.horses aged 30 years and older are commonly classified as “very old”. (categories influenced bygenetic predispositions, individual features, and type of work performed). the first noticeablesigns of aging are seen in horses at around 15 years of age and predominantly during eating, forchanges in dentition and resulting difficulties in chewing; thus, dental prophylaxis is criticallyimportant in this period of life as a lack there of causes weight loss and consequentlydeteriorations in condition because of lower food intake. an easily digestible diet satisfying allrequirements of the body is also important.horses aged older than 15 years are often affected with many diseases associated with old age.these horses have a reduced immunity to infectious diseases because the proliferative capacity oflymphocytes decreases with age, along with a shortening of telomere length(cell lifespan). agerelatedchanges in lymphocyte dna also manifest in oxidative dna damage, estimated via anincreased oxoguanine count, which blocks rna transcription. dna repair insufficiency andmutagen sensitivity, measured with the use of bleomycin-induced chromatid break tests, increasewith horse age, as well. moreover, in old horses, reduced excitability, disturbed concentration,and decreased reactions to the environment are seen, physical strength is reduced, and movementsbecome slower. these dysfunctions are accompanied by decreased bw and degenerative changesin the joints.
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