Alen Dzidic

Prof. Dr. Alen Dzidic

Department of Animal Science, Faculty of Agriculture, University of Zagreb, Zagreb, Croatia
orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

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

Representative Publications

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1 January 2019 in Animal
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Journal Article
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Alen DzidicAlen Dzidic
Alen Dzidic
MRMaristela Rovai
Maristela Rovai
JPJ. L. Poulet
J. L. Poulet
MLM. Leclerc
M. Leclerc
Pierre-Guy MarnetPierre-Guy Marnet
Pierre-Guy Marnet
Small ruminants not only differ on mammary gland anatomy, milk’s properties and the amount of milk yielded comparable to those of dairy cattle, but also on the milking routine strategies and machine milking settings to maximize daily milk secretion. The udder compartment is proportionally larger in dairy sheep and goats, which requires modifications in the milking machine settings, milking procedures and allows the use of different milking strategies as they better tolerate extension of milking intervals. Depending on the breed, cisternal milk in goats varies from 70% to 90%, whereas in dairy sheep it varies from 50% to 78% of the total gland capacity. This explains why these species are commonly milked without pre-milking teat preparation, while in goats it is applied only in cases of high prevalence of intramammary infection in the herd. Recent French researchers observed that 40% of the goats presented an unbalanced udder as well as unbalanced morphology (21% to 30%) and functional milk flow (around 10% to 20% more) which could induce overmilking. In dairy sheep, selection for higher milk production increases teat angle insertion. Thus, to increase machine milk fraction, it is recommended to use either the ‘Sagi hook’ as an alternative for lifting up the ‘pendulous’ udder during milking or to perform machine stripping. There are three cluster removal strategies for small ruminants: manual, timed and milk flow driven automatic cluster removal (ACR). Automatic cluster removal reduces overmilking, improves teat condition, enables labour saving and provides a consistent milking routine in small ruminants. There are three to five main milk flow profiles in ewes and goats, which result in curves with one or two peaks (or plateau) and different patterns of the milk flow decreasing phase due to the degree of mammary gland imbalance and teat characteristics. When taking into account our current knowledge, ACR recommended take-off settings for goats are: 200 g/min+10 s delay time (DT) for a long decreasing phase or two plateau curves and 500 g/min+5 s DT for a short decreasing phase and one plateau curve. The ACR take-off settings for ewes are: 150 g/min +10 s DT for long decreasing phase and 200 g /min+5 s DT for a short decreasing phase. This review is intended to be useful for scientists and producers seeking basic knowledge of milking routines and cluster detachment settings for parlour performance and milk quality.

13 March 2024 in Animals
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Journal Article
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Pierre-Guy MarnetPierre-Guy Marnet
Pierre-Guy Marnet
AVAlejandro Velásquez
Alejandro Velásquez
Alen DzidicAlen Dzidic
Alen Dzidic
There is a need to develop tools for mastitis management in goats and to measure the effects of milking machines on teats. Infrared thermography (IRT), as shown in cows, was a good candidate for early mastitis detection and focusing on milking equipment and settings implicated in potential problems. The aim of this study was to test IRT to detect udder inflammation and the effects of mechanical milking on teats in relation to inflammation status, udder balance, and teat shape in Alpine goats. IRT spectra were compared before and after milking in 551 goats from three commercial herds compared to their individual SCC (somatic cell count). We found no regression or trend between logSCC and IRT measurement or response to milking, even in highly inflamed goat udders. The effect of milking was significant (p < 0.05) with global temperature reduction after milking, but differences were seen between teat parts and unbalanced half udders. The highest reduction in skin temperature was observed at the teat orifice (−1.06 ± 0.05) and the lowest at the teat barrel (−0.37 ± 0.05). The teats with long barrels showed more IRT reactions, which clearly indicates poor adaptation to the liners used. In conclusion, the IRT was not able to detect mastitis, but it is a good tool to diagnose the effects of the milking machine in order to adapt milking equipment and settings to the goats and improve their welfare.

28 January 2015 in Mljekarstvo
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Journal Article
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DSDragica Salamon
Dragica Salamon
Beatriz Gutiérrez-GilBeatriz Gutiérrez-Gil
Beatriz Gutiérrez-Gil
MSMojca Simcic
Mojca Simcic
DKDragomir Kompan
Dragomir Kompan
Alen DzidicAlen Dzidic
Alen Dzidic
Istrian dairy sheep is a local breed essential for the identity and development of the Northern- Adriatic karstic region through high-quality products, primarily the hard sheep artisanal cheese. Border changes fragmented the initial...

1 January 2009 in Italian Journal of Animal Science
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Journal Article
Open access
Alen DzidicAlen Dzidic
Alen Dzidic
DSDragica Salamon
Dragica Salamon
AKAna Kaic
Ana Kaic
KSKresimir Salajpal
Kresimir Salajpal
MKMiroslav Kaps
Miroslav Kaps
The aim of this study was to determine the udder morphology and milking characteristics changes throughout lactation during machine milking of the sheep. Additionally, udder morphology was analyzed by using slide ruler and digital picture. Milking characteristics were influenced by milking interval and day of lactation. Udder morphology traits did not change throughout lactation, except for udder width. The repeatability between slide ruler and digital picture measurements was high (r=0.53 to 0.68). Milkability in Istrian dairy crossbreed ewes could be improved if udder traits are incorporated in selection scheme. Digital picture analysis for faster recording of udder morphology measurements in sheep can be used.

19 February 2024 in Preprints.org
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Preprint
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Pierre-Guy MarnetPierre-Guy Marnet
Pierre-Guy Marnet
AVAlejandro Velásquez
Alejandro Velásquez
Alen DzidicAlen Dzidic
Alen Dzidic
There is a need to develop tools for mastitis management in goats and to measure the effects of milking machines on teats. Infrared thermography (IRT), as shown in cows, was a good candidate for early detection of mastitis and focusing on milking equipment and settings implicated in potential problems. The aim of this study was to test IRT to detect udder inflammation and the effects of mechanical milking on teats in relation to inflammation status, udder balance and teat shape in Alpine goats. IRT spectra were compared before and after milking in 551 goats from three commercial herds compared to their individual SCC (somatic cell count). We found no regression or trend between logSCC and IRT measurement or response to milking, even in highly inflamed goat udders. The effect of milking was significant (P

1 January 2021 in Journal of Central European Agriculture
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Journal Article
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Alen DzidicAlen Dzidic
Alen Dzidic
ŠZŠimun Zamberlin
Šimun Zamberlin
NANeven Antunac
Neven Antunac
DŠDragica Šalamon
Dragica Šalamon
Advances in milk chemistry analytics are in a continuous development for more than one century. Recently, more sophisticated analytical methods became available for a routine performance in the laboratory. On the other hand, some of the methods routinely performed in the laboratory became available for the analyses performed at farm level. Overall, the amount and the resolution of data acquired on daily bases today, enables timely monitoring in the dairy production process. Determining the individual components of milk and dairy products in the laboratory can be accomplished using reference methods, or by using routine methods, which are calibrated using the results of the reference methods. Advanced laboratory analysis of milk and dairy products include sophisticated analytical techniques and equipment such as centrifugation, electrophoresis, chromatography, electron microscopy, dynamic light scattering, neutron and X-ray scattering, rheology, mass spectrometry and proteomic approach, all summarized in this review. Additionally, a synopsis of the methods available in laboratory analytical approach of milk components (protein, fat, lactose, minerals and vitamins) and recent on-farm analytical methods using sensor technology is provided.