Primjena broja somatskih stanica za dijagnostiku mastitisa i utjecaj na kvalitetu mlijeka

master's thesis

• Title (english): Use of Somatic Cell Count for Diagnosis of Mastitis and Impact on Milk Quality
• Author: Klara Knežević
• Mentor: Vesna Dobranić (mentor)
• Mentor: Nino Maćešić (mentor)
• Committee member: Marko Samardžija (predsjednik povjerenstva)
• Committee member: Vesna Dobranić (član povjerenstva)
• Committee member: Nino Maćešić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Veterinary Medicine; Zagreb
• Defense date and country: 2021-03-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Veterinary Medicine; Veterinary Public Health and Food Safety

Abstract

Mastitis je upalna reakcija organizma na infekciju sekretornog dijela mliječne žlijezde.
Uzročnici mastitisa dijele se bojanjem po Gramu na gram-pozitivne i gram-negativne, te prema
etiologiji na kontagiozne i uvjetovane uzročnike. Kontagiozni se uzročnici najčešće prenose
tijekom mužnje, a uzrokuju dugotrajne, kronične mastitise uglavnom subkliničkog tijeka. Za
razliku od njih, uvjetovani uzročnici u pravilu izazivaju kratkotrajne infekcije, ali s češćim
kliničkim manifestacijama. Inficirane krave se otkrivaju dijagnostikom mastitisa, koja se
najčešće provodi neizravnim ili izravnim metodama određivanja broja somatskih stanica i
bakteriološkom pretragom mlijeka. Zagrebački mastitis test je brza i jednostavna orijentacijska
metoda procjene broja somatskih stanica koja se provodi u terenskim uvjetima. Somatske
stanice čine epitelne stanice i leukociti. Normalno se nalaze u mlijeku, ali se njihov broj i odnos
mijenja ovisno o upalnim promjenama u mliječnoj žlijezi. Kretanje broja somatskih stanica
uglavnom ovisi o pojavi mastitisa, ali i o stadiju laktacije, dobi životinje, godišnjem dobu,
ostalim bolestima mliječne krave. Mlijeko sa povećanim brojem somatskih stanica ima
promijenjenu kvalitetu u odnosu na mlijeko zdrave krave. Mlijeko sadrži niži udio mliječne
masti i laktoze, a povećani je udio proteina. Nadalje, povećana je električna provodljivost zbog
povišene koncentracija klora i natrija u mlijeku. Također, ima smanjenu termostabilnost te mu
je smanjena sposobnost podsiravanja i formiranja gruša. Takvo mlijeko ima užegli okus i nije
pogodno za proizvodnju kondenziranog mlijeka, mlijeka u prahu i steriliziranog mlijeka. Rok
trajanja sireva proizvedenog od takvog mlijeka je smanjen zbog zadržavanja veće količine
vode. Pravilnim i redovitim provođenjem postupaka dezinfekcije sisa vimena prije i poslije
mužnje podiže se prinos i kvaliteta mlijeka, odnosno smanjuju se troškovi liječenja mastitisa i
povećava se prihod fame.

Abstract (english)

Mastitis is an inflammatory reaction of the body to an infection of the secretory part of
the mammary gland. The causes of mastitis are divided by Gram staining into gram-positive
and gram-negative, and according to the etiology into contagious and environmental causes.
Contagious pathogens are most transmitted during milking, and cause long-lasting, chronic
mastitis of mostly subclinical course. In contrast, environmental pathogens typically cause
short-term infections, but with more frequent clinical manifestations. Infected cows are
detected by the diagnosis of mastitis, which is most often carried out by indirect or direct
methods of determining the number of somatic cells and bacteriological examination of milk.
The Zagreb mastitis test is a quick and simple orientation method for estimating the number of
somatic cells that is performed in field conditions. Somatic cells are made up of epithelial cells
and leukocytes. They are normally found in milk, but their number and ratio change depending
on inflammatory changes in the mammary gland. The movement of the number of somatic
cells mainly depends on the occurrence of mastitis, but also on the stage of lactation, the age
of the animal, the season and other diseases of the dairy cow. Milk with an increased number
of somatic cells has an altered quality compared to the milk of a healthy cow. Milk contains a
lower proportion of milk fat and lactose, and an increased proportion of protein. Furthermore,
electrical conductivity is increased due to elevated concentrations of chlorine and sodium in
milk. It also has reduced thermal stability and reduced ability to curdle and form lumps. Such
milk has a rancid taste and is not suitable for the production of condensed milk, milk powder
and sterilized milk. The shelf life of cheeses produced from such milk is reduced due to the
retention of a larger amount of water. Proper and regular disinfection of udder teats before and
after milking raises the yield and quality of milk and reduces the cost of mastitis treatment and
increases the income of farm.

• Keywords: mastitis; somatske stanice; mlijeko; kakvoća mlijeka
• Keywords (english): mastitis; somatic cells; milk; milk quality
• Language: croatian
• URN:NBN: urn:nbn:hr:178:357423
• 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: 2021-04-14 09:52:32