Nikolina Kelava Ugarković

Dr. Nikolina Kelava Ugarković

Department of Animal Science and Technology, University of Zagreb, 10000 Zagreb, Croatia
orcid

Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

View All Publications
29 June 2023 in Animals
Verified
Journal Article
Open access
PDF file
Ante IvankovicAnte Ivankovic
Ante Ivankovic
GŠGordan Šubara
Gordan Šubara
Giovanni BittanteGiovanni Bittante
Giovanni Bittante
EŠEdmondo Šuran
Edmondo Šuran
NANicolò Amalfitano
Nicolò Amalfitano
MKMiljenko Konjačić
Miljenko Konjačić
The problem of the erosion of animal genetic resources is evident in certain local donkey breeds, and their long-term sustainability can be achieved by economically repositioning them. To develop alternative and sustainable commercial programs, the meat and milk production characteristics of Istrian donkey and Littoral Dinaric donkey breeds were investigated. The meat production characteristics were examined in mature males, whose carcasses were dissected, and meat composition was determined using NIT spectrophotometry and gas chromatography. Milk yield and milk composition were determined in jennies in second or subsequent lactations by measuring milk volume and using infrared spectrometry and gas chromatography. Compared to the Littoral Dinaric donkey, the Istrian donkey has a higher carcass weight and dressing percentage (p < 0.001). The share of boneless meat in relation to live weight was 28.27% in the Istrian donkey and 26.18% in the Littoral Dinaric donkey. The absolute masses of primal cuts of meat in E, I, and II classes were significantly greater in Istrian donkeys than in Littoral Dinaric donkeys (p < 0.01), although the differences in the proportions of primal cuts were not significant. The breed did not have a significant impact on the color, pH, or meat composition. A significant influence of breed on milk yield, lactose, protein, and the fat content of milk was observed (p < 0.01). A significant influence of breed on the ratio of n-6/n-3 PUFA fatty acids in donkey milk was observed (p = 0.002). The values of the atherogenic and thrombogenic indexes were favorable, considering potential beneficial effects of donkey milk and meat on consumer health. The findings of this research suggest that local donkey breeds hold significant potential for meat and milk production, focusing on the uniqueness and quality of their products rather than the quantity of meat and milk they can produce.

25 March 2020 in Mljekarstvo
Verified
Journal Article
Open access
PDF file
JVJosip Vrdoljak
Josip Vrdoljak
Zvonimir PrpićZvonimir Prpić
Zvonimir Prpić
DSDubravka Samaržija
Dubravka Samaržija
Ivan VnučecIvan Vnučec
Ivan Vnučec
MKMiljenko Konjačić
Miljenko Konjačić
Nikolina Kelava UgarkovićNikolina Kelava Ugarković
Nikolina Kelava Ugarković
In recent years there has been an increasing trend in research of sheep and goat udder morphology, not only from the view of its suitability for machine milking, but also in terms of milk yield and mammary gland health. More precisely, herds consisting of high-yielding sheep and goats as a result of long-term and one-sided selection to increase milk yield, have been characterised by distortion of the udder morphology caused by increasing the pressure of udder weight on its suspensory system. Along with the deteriorated milking traits, which is negatively reflected on the udder health, some udder morphology traits are often emphasized as factor of production longevity of dairy sheep and goats. Since the intention of farmers and breeders nowadays is to increase the milk yield of sheep and goats while maintaining desirable udder morphology and udder health, the aim of this paper is to give a detailed overview of the current knowledge about the relationship of morphological udder traits with milk yield, and the health of the mammary gland of sheep and goats. External measures of udder size (circumference, width and depth of the udder) are strongly correlated with milk production in sheep and goats. The morphological udder traits determining its suitability for machine milking (such as teat position and teat angle, udder depth, teat size, cistern height) are related to the mammary gland health in sheep and goats. Thus, the incidence of mastitis is noticeably higher in the udders of unsuitable shape for machine milking (deep and hung udders, unfavourable position of teats, etc.). Consequently, the morphological udder traits that affect the milkability of sheep and goats are indirectly related to milk yield.

12 April 2021 in Animals
Verified
Journal Article
Open access
PDF file
Ana KaićAna Kaić
Ana Kaić
ZJZlatko Janječić
Zlatko Janječić
AŽAndrija Žanetić
Andrija Žanetić
Nikolina Kelava UgarkovićNikolina Kelava Ugarković
Nikolina Kelava Ugarković
KPKlemen Potočnik
Klemen Potočnik
Although the EZ-DripLoss method has been performed in numerous studies, there is a deficiency in our knowledge of the EZ-DripLoss method’s suitability for poultry meat analysis. This study aimed to research the effect of different sample areas (10, 20, and 30 mm; n = 240), and fiber orientations (vertical vs. horizontal) on the EZ-DripLoss in chicken breast meat measured across a period of five days. The influence of sample area on the EZ-DripLoss of chicken breast meat with respect to the fiber orientation and across the five-day measurement interval was significant between 10 and 30 mm samples, and between 20 and 30 mm samples (p < 0.001). The estimated regression coefficient showed that EZ-DripLoss for the samples with horizontal and vertical fiber direction of 10 and 20 mm, significantly increased by 0.04% per hour, while for the samples with vertical fiber direction whose diameter was 30 mm, it significantly increased by 0.06% per hour, and for the horizontal fiber direction, it significantly increased by 0.07% per hour. The samples with vertical fiber orientation had 0.50% greater EZ-DripLoss compared to the samples with horizontal fiber orientation. EZ-DripLoss evaluation in chicken breast should be performed with a sample core diameter of 20 mm, a vertical fiber orientation, and over the course of longer measurement intervals.

26 February 2023 in Agriculture
Verified
Journal Article
Open access
PDF file
Mateja PećinaMateja Pećina
Mateja Pećina
MKMiljenko Konjačić
Miljenko Konjačić
Nikolina Kelava UgarkovićNikolina Kelava Ugarković
Nikolina Kelava Ugarković
Ante IvankovicAnte Ivankovic
Ante Ivankovic
To improve beef quality, a selection of specific breeds for crossbreeding, genotyping, and selection of specific candidate genes in breeding animals can be some of the solutions. The objective of this study was to determine the effects of FASN, SCD, and GH genes on carcass fatness and fatty acid (FA) composition of intramuscular lipids of crossbred Holstein × beef breeds (Simmental, Belgian Blue, Limousin, and Piemontese). The allelic and genotypic distribution of polymorphisms in the FASN, SCD, and GH genes was studied in 80 crossbreed animals. Genomic DNA was isolated from musculus longissimus dorsi, whose chemical composition was determined by near infrared transmittance spectrophotometry, while the fatty acid composition was determined by gas chromatography. DNA polymorphism was analyzed by restriction fragment length polymorphism analysis. The FASN (g. 17924A>G) polymorphism was significantly associated with C19:1 n-9 and C24:1 n-9, whereas GH (g.2141C>G) was significantly associated with C16:0 and C20:1 n-9. The SCD (g.8586C>T) polymorphism was significantly associated with C16:0, C18:0, C20:0, C14:1 n-5, C16:1, C18:1, C18:2 n-6, C18:3 n-3, C20:2 n-6, and C20:4 n-6, and analyzed the sum and ratios of fatty acids. Sex had significant effect on carcass fatness and fatty acid composition. This study provided useful results for the above candidate genes and their association with some FA, supporting their influence as genes associated with fats and fatty acid composition in beef meat.

21 April 2022 in Diversity
Verified
Journal Article
Open access
PDF file
Ante IvankovicAnte Ivankovic
Ante Ivankovic
Giovanni BittanteGiovanni Bittante
Giovanni Bittante
GŠGordan Šubara
Gordan Šubara
EŠEdmondo Šuran
Edmondo Šuran
ZIZdenko Ivkić
Zdenko Ivkić
Jelena RamljakJelena Ramljak
Jelena Ramljak
The two native Croatian donkey breeds (Littoral-Dinaric donkey and Istrian donkey) were marginalized in the second half of the 20th century and were on the verge of biological extinction. The aim of this study was to analyze the demographic and genetic status of two donkey breeds, two decades after the start of protection by analyzing their pedigrees and genetic structure. The average generation interval was higher for the Istrian donkey (7.73) than for the Littoral-Dinaric donkey (7.27). The rate of the effective number of founders compared with the effective number of ancestors in the Littoral-Dinaric donkey (1.03; 325/316) and in the Istrian donkey (1.08; 70/65) revealed no evidence of a genetic bottleneck. The inbreeding coefficient (F) and the average relatedness coefficient (AR) was lower in the Littoral-Dinaric donkey population (0.99%; 0.13%) than in the Istrian donkey population (1.77%; 1.10%). Genetic microsatellite analysis showed relatively high genetic diversity in Littoral-Dinaric donkey and Istrian donkey breeds, expressed by mean allele number (5.92; 5.85) and expected heterozygosity (0.650; 0.653). Genetic differentiation between the Littoral-Dinaric donkey and the Istrian donkey has not significantly increased in the last two decades (FST = 0.028). Genetic analysis also showed no evidence of high inbreeding or genetic bottleneck in both breeds. A total of 11 haplotypes including 28 polymorphic sites were found in 30 samples. Analysis of mtDNA has shown that the Littoral-Dinaric donkey and Istrian donkey breeds belong to the Equus asinus africanus group. The study confirms the need to use different analytical approaches to get a regular and complete insight into the situation and trends within and between breeds, so that the existing diversity can be fully preserved.

24 December 2020 in Foods
Verified
Journal Article
Open access
PDF file
Nikolina Kelava UgarkovićNikolina Kelava Ugarković
Nikolina Kelava Ugarković
MKMiljenko Konjačić
Miljenko Konjačić
JMJosip Malnar
Josip Malnar
Kristijan TomljanovićKristijan Tomljanović
Kristijan Tomljanović
NSNikica Sprem
Nikica Sprem
DUDamir Ugarkovic
Damir Ugarkovic
Although game meat quality has been under the spotlight in numerous studies, the quality of brown bear (Ursus arctos) meat is still unknown. The aim of this study was to determine the effects of sex and age on the proximate chemical composition, fatty acid profile, and lipid indices of brown bear meat. Nine (n = 9) females and nine (n = 9) males were hunted during the Croatian spring hunting period in 2018. Based on age, bears were divided into two groups: <3 years (n = 9; five females and four males) and 4–6 years (n = 9; four females and five males). For analysis purposes, samples of M.semimembranosus were collected. Age was shown to have an effect on the traits analyzed, while sex-related differences were not found. Brown bear meat has a high fat content (average 6.12%), especially in older bears (~9%). The contents of protein, dry matter, and ash were similar to those of other game species. Monounsaturated fatty acids made up approximately 50% of all fatty acids, with the most abundant being C18:1n-9. More favorable profiles of essential polyunsaturated fatty acids were found in younger bears. The ratio of polyunsaturated and saturated fatty acids was closer to the recommended ratio than the ratio of n-6 and n-3 polyunsaturated fatty acids, and lipid indices were favorable. Further research is needed to determine seasonal changes in brown bear meat quality.