Utjecaj broja jarića i stadija laktacije na masne kiseline mlijeka i seruma koza

master's thesis

• Title (english): The Effects of Litter Size and Stage of Lactation on the Fatty Acid Profile of Serum and Milk in Goat
• Author: Marta Šurbek
• Mentor: Lana Vranković (mentor)
• Mentor: Antun Kostelić (mentor)
• Committee member: Jasna Aladrović (predsjednik povjerenstva)
• Committee member: Antun Kostelić (član povjerenstva)
• Committee member: Lana Vranković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Veterinary Medicine; (Department of Physiology and Radiobiology); Zagreb
• Defense date and country: 2019-09-11, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Veterinary Medicine; Basic and Preclinical Veterinary Sciences

Abstract

Masnokiselinski sastav specifičan je za pojedinu vrstu i tkivo, no podložan je promjenama ovisno o hranidbi i metaboličkim procesima u organizmu. Masnokiselinski sastav mlijeka od iznimnog je značaja za kvalitetu mlijeka, a masne kiseline krvi izvor su otprilike polovine masnih kiselina mlijeka. Cilj ovog rada bio je utvrditi razlike u masnokiselinskom profilu seruma i mlijeka koza s obzirom na broj mladunčadi u leglu i različite faze proizvodnog ciklusa. Istraživanje je provedeno na 30 klinički zdravih koza sanske pasmine. Nakon ekstrakcije ukupnih lipida iz uzoraka seruma i mlijeka, analiza metilnih estera masnih kiselina provedena je plinskom kromatografijom (GC). U mlijeku i serumu koza dominiraju zasićene masne kiseline (SFA) s C16:0 kao najzastupljenijom zasićenom masnom kiselinom, bez obzira na broj mladunčadi i stadij laktacije. Tijekom suhostaja je u serumu utvrđen značajno manji postotak nezasićenih masnih kiselina (UFA) u odnosu na laktacijsko razdoblje (p<0,050), a u mlijeku je u ranoj laktaciji utvrđeno manje jednostrukonezasićenih masnih kiselina (MUFA) u odnosu na kasnu laktaciju. Utvrđene su i razlike u zastupljenosti pojedinih masnih kiselina u serumu i mlijeku tijekom različitih proizvodnih faza. U kasnoj laktaciji u serumu koza s jednim jarićem u leglu utvrđen je veći postotak C16:0 i C18:0 (p<0,050). U mlijeku koza s jednim jarićem u leglu u ranoj laktaciji utvrđeno je manje jednostrukonezasićenih masnih kiselina (MUFA), C18:1c9, C8:0 i više C12:0 (p<0,050). Na osnovi ovakvih rezultata možemo zaključiti da stadij laktacije utječe na masnokiselinski sastav seruma i mlijeka koza te broja jarića utječe na masnokiselinski sastav mlijeka tijekom rane laktacije.

Abstract (english)

The fatty acid composition is species and tissue specific, however it is susceptible to change depending on the diet and the metabolical processes inside the organism. The fatty acid composition of milk is of exceptional importance for the quality of milk, and approximately half of the fatty acids in the milk are sourced from the blood. The main focus of this thesis was to determine the differences in the fatty acid profile of goat serum and milk, depending on the brood size and various phases of the production cycle. The research was carried out on 30 clinically healthy Saanen goats. After the extraction of total lipids from the serum and milk samples, the analysis of methyl esters of fatty acids was performed using gas chromatography (GC). Predominating in milk and serum are the saturated fatty acids (SFA), with C16:0 being the most common, regardless of the litter size or the lactation stage. In dry period, a much smaller percentage of serum unsaturated fatty acids (UFA) was determined compared to the lactation period (p<0,050), and in the milk, during the early lactation, there were much less monounsaturated fatty acids (MUFA) than during the late lactation. Some differences were also found in individual fatty acids in the serum and the milk in various production stages. In late lactation, there was a higher percentage of C16:0 and C18:0 (p<0,050) in the serum of goats with one kid. During early lactation in the milk of goats with one kid there were less (MUFA), C18:1c9, C8:0 and more C12:0 (p<0,050). Based on these results, we could conclude that the lactation period affects the fatty acid composition of goat milk and serum. The litter size affects the fatty acid composition of the milk in early lactation.

• Keywords: sanska koza; serum; mlijeko; masnokiselinski sastav
• Keywords (english): Saanen goat; serum; milk; fatty acid composition
• Language: croatian
• URN:NBN: urn:nbn:hr:178:062840
• Study programme: Title: Veterinary Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica veterinarske medicine (doktor/doktorica veterinarske medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2020-01-28 12:16:28