Utjecaj trajanja miješanja sirovina na kemijski sastav i krupnoću čestica potpuno izmiješanog obroka junadi u tovu

master's thesis

• Title (english): Influence of mixing time on mixing uniformity and particle sizes distribution in total mixed diet for cattle
• Author: Goran Mikec
• Mentor: Darko Grbeša (mentor)
• Committee member: Darko Grbeša (predsjednik povjerenstva)
• Committee member: Goran Kiš (član povjerenstva)
• Committee member: Miljenko Konjačić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Department of Animal Nutrition); Zagreb
• Defense date and country: 2020-09-24, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Cilj ovog diplomskog rada je odrediti kako duljina trajanja miješanja obroka (TMR) u mikser prikolici utječe na ujednačenost miješanja i udio pojedinih čestica . Istraživanje je provedeno na gospodarstvu na izmješanom krmivu kojim se hrani 170 grla simentalske tovne junadi i junica. Sijeno livadno, sjenaža lucerne, silaža kukuruza, visoko vlažno zrno kukuruza i dopunska krmna smjesa su miješani 45 i 90 minuta u mikser prikolici (5m3) Sano Profi Mini i istovareni na hranidbeni stol. Uzorci obroka su uzimani sa početka, sredine i kraja hranidbenog stola svakodnevno tijekom dva tjedna.
U prosušenim zorcima obroka prosijavanjem na Penn State Particle Seperator sitima veličine 19 mm, 8 mm i 1.18 mm određena je veličina čestica, a koncetracija natrija je bila pokazatelj iziješanosti obroka. U uzorcima je određen udjel suhe tvari, natrija, sirovih proteina i neutralnih deterdžent vlakana. Miješanje obroka 90 i 45 minuta dobije se odlična izmješanost (< 5%) obroka mjerena koncetracijom natrija u suhoj tvari. Miješanje u trajanju 90 min daje manje dnevne varijacije. Miješanje i usitnjavanje hrane tijekom 90 minuta i 45 minuta rezultira prosječnom veličinom koja osigurava više od minimalno potrebne količine efektivnih valakan za održavanje normalne kiselost buraga. Međutim, miješanje od 90 minuta daje ujednačeniju raspodjelu veličina vlakana tijekom tjedan dana mjerenja što osigurava ravnomjernu količinu svake frakcije vlakana junadi u svakom boksu cijekom cijelog tova.
Zaključno, suhe obroke u maloj mikser prikolici bolje je miješati 90 nego 45 minuta.

Abstract (english)

The aim of this master thesis was to assess the effect length of a mixing time of total mixed ration (TMR) for beef on its uniformity and distribution of particle size. Research was conducted on a small family farm on 170 Simental bulls and heifers fed with the same ration composed of meadow and alfalfa hay, corn silage, high moisture corn and complementary feed mixed with maize. One-week all cattle fed with TMR mixed for 90 min and another week with the same TMR mixed 45 min in small (5m3) TMR Sano Profi Mini mixer.
The sodium content in dry matter used as an indicator of the consistency of total mixed ration and particles size distribution of TMR were determined using Pen State Particles Separator with three size holes size 19 mm, 8 mm, and 1.18 mm. Uniformity from TMR mixing 90 and 45 min measured by coefficient of variation was excellent (< 5%), but 90 min mixing time obtained lower day to day variation. Particle size distribution was generally according the standard for both times. Geometric means of particle length for both mixing times were 4.38 mm and 4.82 mm and assured adequate amount of effective neutral detergent fibre for beef. Ration mixed longer time had less long fibre and more middle (1.18 – 8 mm) particle size and that indicate better cutting of forages. But, mixing 90 min resulted with more consistent uniformity among the day of investigation.
These result of the investigation indicate that 90 min mixing in small mixer improved consistency of TMR over time and uniformity under and between of particle size fractions.

• Keywords: TMR; vrijeme miješanja; ujednačenost; veličina čestica; efektivna vlakna
• Keywords (english): total mixed ration; mixing time; uniformity; particle size distribution; effective fibre
• Language: croatian
• URN:NBN: urn:nbn:hr:204:660193
• Study programme: Title: Animal Nutrition and Feed Science; Study programme type: university; Study level: graduate; Academic / professional title: magistar/ magistra inženjer/inženjerka hranidbe životinja i hrane (magistar/ magistra inženjer/inženjerka hranidbe životinja i hrane)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-10-13 07:35:22