Hranilna vrednost travne silaže in njena primernost za prehrano krav molznic na nekaterih kmetijah v Sloveniji

Košnjek, Katarina (author), Pirman, Tatjana (mentor)

V okviru magistrske naloge smo preučevali hranilno vrednost travnih silaž med leti 2018 in 2022 iz kmetij osrednjeslovenske regije. V raziskavo smo vključili 139 vzorcev travnih silaž prve, druge in nadaljnjih košenj, ki so jih analizirali s pomočjo NIRS v laboratoriju LKS v Nemčiji. Povprečna vsebnost suhe snovi (SS) analiziranih travnih silaž je bila 425 g/kg. Povprečne vsebnosti ostalih analiziranih kazalnikov so naslednje: surovi pepel (SP) 102 g/kg SS, surove beljakovine (SB) 137 g/kg SS, surova vlaknina (SV) 270 g/kg SS, surove maščobe (SM) 32 g/kg SS, sladkorji 56 g/kg SS, hohenheimski plinski test (HFT) 43,8 ml/200 mg SS, organska snov v kislem detergentu netopne vlaknine (KDVom) 303 g/kg SS, pH vrednost 4,72, amoniačni dušik (NH3-N) 7,5 %, v pepsinu nerazgradljive beljakovine (PNB) 26,2 %, delež topnih beljakovin (DTB) 54,2 %, presnovljiva energija (ME) 9,59 MJ/kg SS, neto energija za laktacijo (NEL) 5,68 MJ/kg SS, izkoristljive surove beljakovine (nXP) 126 g/kg SS in bilanca dušika v vampu (RNB) 2,0 g/kg SS. Z analizo variance smo ocenili vpliv leta in zaporedne košnje na hranilno vrednost travnih silaž. Statistično značilne razlike znotraj let smo potrdili pri vsebnosti SM, sladkorjih, HFT, pH vrednosti, NH3-N in RNB. Statistično značilno višje vsebnosti SB, nXP in RNB so imele silaže druge in nadaljnjih košenj, medtem ko je bila vsebnost SV in HFT statistično značilno višja pri prvi košnji. Statistično značilne in pozitivne ocene korelacijskih koeficientov smo potrdili med DTB in HFT (r = 0,336) ter SS in HFT (r = 0,192). Statistično značilne vendar negativne ocene korelacijskih koeficientov med SP in HFT (r = -0,432), PNB in HFT (r = -0,456), NH3-N in HFT (r = -0,322), KDVom in HFT (r = -0,316) ter pH in HFT (r = - 0,257). Največjo oceno korelacije pa smo ugotovili med sladkorji in HFT (r = 0,762).

• Language: Slovenian
• Keywords: govedo, krave, molznice, prehrana živali, travna silaža, hranilna vrednost, Slovenija
• Work type: Master's thesis/paper
• Organization: BF - Biotechnical Faculty
• Year: 2024
• PID: 20.500.12556/RUL-155661
• COBISS.SI-ID: 193288707
• Publication date in RUL: 11.04.2024

Secondary language

• Language: English
• Title: Nutritional value of grass silage and its suitability for dairy cows nutrition on some farms in Slovenia

Abstract

The objective of the M. Sc. Thesis was to study the nutritional value of grass silage between 2018 and 2022 from farms in the Central Slovenian region. The study included 139 grass silage samples of first, second and subsequent mowing, which were analysed by NIRS at the LKS laboratory in Germany. The mean dry matter (DM) content of grass silage analysed was 425 g/kg. The average content of the other indicators analysed is as follows: crude ash 102 g/kg DM, crude protein 137 g/kg DM, crude fibre 270 g/kg DM, crude fat 32 g/kg DM, sugars 56 g/kg DM, Hohenheim gas test (HFT) 43.8 ml/200 mg DM, organic matter of acid insoluble detergent fibre (KDVom) 303 g/kg DM, pH 4.72, ammonia nitrogen (NH3-N) 7.5 %, pepsin insoluble protein (PNB) 26.2 %, soluble protein content 54.2 %, metabolic energy 9.59 MJ/kg DM, Net energy of lactation (NEL) 5.68 MJ/kg DM, usable crude protein (nXP) 126 g/kg DM and nitrogen balance in the rumen (RNB) 2,0 g/kg DM. By analyzing variance, we assessed the impact of year and successive mowing on the nutritional value of grass silage. Statistically significant differences over the years were confirmed for crude fats, sugars, HFT, pH, NH3-N and RNB. Statistically significantly higher levels of crude protein, nXP and RNB had silage of second and further mowing, while crude fiber and HFT content was statistically significant higher for the first mowing. Statistically significant and positive estimation of correlation coefficients were confirmed between soluble protein content and HFT (r = 0.336) and DM and HFT (r = 0.192). Statistically significant but negative estimation of correlation coefficients were confirmed between crude ash and HFT (r = -0.432), PNB and HFT (r = -0.456), NH3-N and HFT (r = -0.322), KDVom and HFT (r = -0.316), and pH and HFT (r = - 0.257), However, the highest correlation score was found between sugars and HFT (r = 0.762).

• Keywords: cattle, dairy cows, animal nutrition, grass silage, nutritional value, Slovenia