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V diplomskem projektu smo predstavili krmljenje telet po volji kot alternativno vzrejo v primer-javi s konvencionalno vzrejo telet, kjer je zauživanje mleka oz. mlečnega nadomestka omejeno. Pri tej vzreji teleta v predodstavitvenem obdobju popijejo tudi do 20 % telesne mase na dan v obliki mlečnega nadomestka ali polnomastnega mleka. Ker je zelo po-membno, da teleta do odstavitve dosegajo čim večje priraste, je potrebno urediti dnevni obrok tako, da teleta lahko zaužijejo o čim več hranljivih snovi. Le te so ključ do hitre rasti in dobrega razvoja vseh organov in organskih sistemov. Potrebno je uskladiti tekoči obrok in od drugega tedna dalje tudi suhi obrok s štarterjem in senom. Pri tem moramo biti pozorni, saj so teleta v glavnem še neprežvekovalci in je njihov glavni obrok še zmeraj tekoča krma. Če to ne upoštevamo, teleta izpostavljamo stresu, posledično manj pojedo in slabše priraščajo. Dobro razvito tele v predodstavitvenem obdobju, običajno tudi po odstavitvi še naprej dobro prirašča, posledično prej spolno dozori in tako rejcu omogoča zgodnejšo reprodukcijo. Rezultat dobre vzreje telet se odrazi tudi na poznejši mlečnosti, saj različni raziskovalci ocenjujejo, da se lahko v prvi laktaciji mlečnost po-veča tudi za do 4 %. In B. Sc. Thesis, we presented ad libitum feeding of calves until weaning as an alternative to conventional restricted milk feeding. In this alternative method, calves can drink up to 20 % of their body weight per day in the form of milk replacer or whole milk during the period before weaning. Since it is very important that calves achieve the highest growth rate possible before weaning, the daily ratio must be managed to allow calves to consume as many nutrients as possible. Nutrients are key to rapid growth and development of all organs and organ systems. It is necessary to coordinate liquid feeding and, beginning in the second week, dry feeding with a starter and hay. Care must be taken as calves are mostly still non-ruminants and their main part of the feed ratio is still liquid feed. If we do not take this into account, calves will be exposed to stress, resulting in lower feed intake and growth rate. A well-developed calf in the pre-weaning period continues to grow well, consequently reaching sexual maturity earlier and also allowing for earlier reproduction. The result of good calf rearing is also reflected in later milk yield, as various researchers estimate that milk yield can increase by up to 4 % in the first lactation.

Pri primerjavi literaturnih virov se vidi, da se meso govedi spitanih z voluminozno krmo, pašo, v primerjavi z mesom govedi spitanih pretežno z močnimi krmili, najbolj razlikuje v kemični sestavi. Običajno vsebuje meso govedi spitanih z voluminozno krmo več antioksidantov, vitaminov in njihovih prekurzorjev ter manj maščob, z izboljšano maščobnokislinsko sestavo. Intramuskularna maščoba vsebuje običajno nekoliko več nasičenih in manj enkrat nenasičenih ter predvsem več večkrat nenasičenih maščobnih kislin, vakcenske, konjugirane linolne kisline in n-3 maščobnih kislin ter s tem tudi ugodnejše, ožje, razmerje n-6: n-3 maščobnih kislin. Z manjšo vsebnostjo intramuskularne maščobe je pogosto povezano poslabšanje senzoričnih lastnosti mesa, predvsem mehkobe in sočnosti. Spremenjena maščobnokislinska sestava pa vpliva tudi na okus mesa. Barva mesa je lahko bolj intenzivno rdeča in rumena, kar je za potrošnike nezaželeno, po drugi strani pa je boljša obstojnost barve mesa, kar je izrazito pozitivno. Pri interpretaciji teh razlik pa moramo biti previdni, saj je krma samo eden izmed dejavnikov, ki vplivajo na lastnosti mesa. Upoštevati moramo tudi druge dejavnike (pasmo, spol, starost, telesno maso, ravnanje z živalmi pred zakolom in s klavnimi polovicami po zakolu) in njihove medsebojne interakcije, ki vplivajo na lastnosti mesa in s tem na njegovo kakovost. The reviewed literature suggested that meat from cattle fattened on grass-based diets compared to grain based diets differ mostly in chemical composition. Beef from grassbased diets usually contains more antioxidants, vitamins, their precursors and less fat with improved fatty acid composition. Intramuscular fat usually contains slightly more saturated and less monounsaturated, and particularly more unsaturated fatty acids, vaccine, conjugated linoleic acid and n-3 fatty acids, and thus a more favorable, narrower n-6/n-3 ratio of fatty acids. A lower intramuscular fat content is often associated with a deterioration of the sensory properties of the meat, especially tenderness and juiciness. The modified fatty acid composition also affects meat aroma. The color of the meat can be more intensively red and yellow, which is undesirable for consumers on the other hand, meat colour stability is improved, which is clearly positive. However, when interpreting these differences, we must be careful, as feed is one of many factors that influence meat characteristics. We must also consider other factors (breed, sex, age, body mass, handling of animals before slaughter and carcasses after slaughter) and their interactions, which affect meat characteristics and its quality.

V nalogi smo se osredotočili na ocenjevanje vsebnosti hranil v enolončnicah za krave molznice z metodo bližnje infrardeče refleksijske spektroskopije. Želeli smo preveriti ali ima ta fizikalna metoda potencial za ocenjevanje tovrstnih mešanic krme. Enolončnice smo pripravili v laboratoriju iz posušenih vzorcev krme. Hranilne vrednosti enolončnic smo prikazali v preglednicah. Na podlagi zmešanih enolončnic smo s pomočjo računalniškega programa WinISI izdelali napovedne enačbe. Napovedno moč teh enačb smo preverili z validacijskimi enolončnicami, rezultate skeniranja pa smo prikazali grafično ter v preglednicah. Parametri umeritvenih enačb za sestavine krme (surove beljakovine, surova vlaknina, surovi pepel, surove maščobe) in energijsko vrednost (presnovljiva energija, neto energija za laktacijo ) so bili odlični (R2>0,99), validacija z neodvisnim validacijskim setom vzorcev pa je pokazala, da so enačbe premalo robustne. Predlagali smo, da bi bilo treba napovedne enačbe izboljšati z večjim številom med seboj bolj raznolikih enolončnic. Our focus in this thesis was evaluation of nutritional value of mixed rations for dairy cows using near infrared reflectance spectroscopy. Our goal was to establish if this physical method has a potential to evaluate composition of mixed rations. The mixed rations were prepared in a laboratory using dried feed samples. The nutritional values of mixed ratios were presented in tables. The predictive equations were developed by the use of WinISI computer program. We have tested the accuracy of predictive equations using validation sample set. The results were presented in tabels and gaphically. Parameters of calibration equations for feed ingredients (crude protein, crude fiber, raw ash, raw fats) and energy value (metabolizable energy, net energy for lactation) were excellent (R2> 0.99), however, validation with an independent validation set of samples showed that equations are not robust enough. It was suggested that the predictive equations should be improved with a greater number of more variable mixed ratios.