Analysis of lactoferin gene polymophism and its association to milk quality and mammary gland health in Holstein-Friesian cows

Lactoferrin (LTF) is a glycoprotein, a member of transferrin gene family which plays an important role in immune mechanisms in the mammary glands of cows. The amount of lactoferrin increases during inflammatory processes and viral infections. The aim of this investigation was to monitor the distribution of lactoferrin gene genotypes and its connection to milk quality and the occurrence of mammary gland diseases in 46 Holstein-Freisian cows of different age (2-7 years) on a farm near Belgrade. DNA was isolated from blood samples, and the polymorphism of lactoferrin gene was deterimined by PCR-RFLP method using the restriction enzyme Eco RI. We found two alelic forms of this gene in cows included in these experiments (A and B) and two genotypes (AA and AB) in a ratio 71.7% to 28.3%. The genotype BB was not found in this sample. In order to determine the degree of differences between genotypes we used discriminant analysis which has shown that there is a statistically significant difference between genotypes AA and with respect to productive parameters. When analyzed separately, the only parameter which differed significantly (p=0.021) between two genotypes was total milk production. Individuals with observed genotypes are most similar for the amount of milk fat (p=0.271). There is no statistically significant difference in the number of somatic cells in milk samples between the examined genotypes. [Projekat Ministarstva nauke Republike Srbije, br. III46002

Gastrointestinal parasites in owned dogs in Serbia: Prevalence and risk factors

Dogs are the most popular pets worldwide. Close contact between dogs and people increases the risk of transmission of various zoonotic parasitic infections. Given the importance of veterinary medicine in preserving the One Health concept, the aim of this research was to identify intestinal parasites that may have zoonotic potential and to evaluate risk factors (individual and environmental). The research was conducted in Serbia in 2022 and 2023 on 382 owned dogs, using qualitative methods of coprological examination with a concentration on parasitic elements. The overall prevalence of intestinal parasites was 62.6%, with the following detected: protozoa: Cystoisospora spp. (9.2%), Sarcocystis spp. (4.5%), Neospora caninum/Hammondia spp. (3.7%), Giardia intestinalis (11.8%); nematoda: Toxocara canis (11.5%), Toxascaris leonina (4.2%), family Ancylostomatidae (38.0%), Trichuris vulpis (21.5%), Capillaria spp. (10.5%); trematoda: Alaria alata (1.6%) and cestodes from the Taeniidae family (1.3%). Factors like age, size and coat length, as well as the way of living, attitude and diet were linked to a significantly higher (p < 0.05) prevalence of intestinal parasites. Based on the results of coprological diagnostics, this research indicates the importance of educating dog owners, conducting routine parasitological tests on their pets and regular deworming strategies

Analysis of association lactofferin (LTF) gene polymorphism with mammary gland health and production characteristics of Holstein-Friesian cows

Brzi razvoj molekularne genetike tokom posledenje tri decenije omogućio je direktnu analizu genoma životinja, proučavanje strukture i funkcije gena, pa samim tim pomogao boljem razumevanju delovanja nasledne osnove. Molekularno-genetičke metode omogućile su uvid u nekodirajuće delove genoma, koje kod sisara čine više od 90%. DNK (dezoksiribonukleinska kiselina) zapisa. U slučаjevimа gde se prаte osobine koje su generаlno sа niskim heritibilitetom, kаo što je slučаj sа otpornošću nа mаstitis, MAS (mаrker аsistirаnа selekcijа) ili genomskа selekcijа pokаzаle su bolji rezultаt u odnosu nа konvencionаlni metod selekcije. Primаrni cilj u ispitivаnju kаndidаt-genа povezаnih sа pojаvljivаnjem mаstitisа je identifikаcijа genа koji su uključeni u proces imunog odgovorа mlečne žlezde. Laktoferin gen (LTF) se u većem broju istraživanja pominje kao validni molekularni marker u praćenju procesa otpornosti mlečne žlezde prema infekciji. Cilj ovog rada bio je ispitivanje polimorfizma gena za LTF i njegov uticaj na zdravstveni status mlečne žlezde i proizvodne karakteristike krava holštajnfrizijske rase u Srbiji. Ogled je obuhvatao 100 krava različite laktacione starosti (1.-4. laktacija) na farmi blizu Beograda. Životinje su bile ravnomerno raspoređene u grupama po laktacionoj starosti (χ2=0,578; p=0,902). Posle ekstrakcije DNK iz krvi amplifikovan je fragment gena za laktoferin na intronu 6 metodom PCR (polymerase chain reactionreakcija lančane polimeraze). Pomoću specifičnih prajmera, identifikovana su dva genotipa AA i AB od moguća tri, (BB nije identifikovan) metodom PCR-RFLP (Restriction Fragment Lenght Polymorphism-polimorfizam u dužini restrikcionih fragmenata). U cilju ispitivanja zdravstvenog statusa mlečne žlezde, kvalitativnog sastava i ukupne proizvodnje mleka, svakog meseca kroz period standardne laktacije od 305 dana, su uzimani uzorci mleka. Broj somatskih ćelija (SCC) određivan je mikroskopski a koncentracija proteina i mlečne masti utvrđivana je spektrofotometrijski (aparat Milkoscan). U zajedničkom uzorku od 90 krava, konstatovana je statistički vrlo značajno veća (χ2=40,894; p<0,001) zastupljenost genotipa AA ( 74 ili 82,22%) u odnosu na zastupljenost genotipa AB ( 16 ili17,78%). Prema Hardy-Weinberg jednačini odnos genotipova AA, AB i BB se nalazi u ravnoteži (p=0,3547). Distribucija A alela u posmatranoj populaciji bila je 91,11% a B alela 8,89%. Ovako visok broj homozigota ukazuje na smanjeni protok gena u populaciji i veći stepen genetske konzervisanosti zapata. Poizvodne karakteristike praćenih genotipova nisu se statistički razlikovale...The rapid development of molecular genetics during last three decades has facilitate the direct analysis of the genome of animals and insight in gene structure and function, and thus helped to a better understanding basis of genetic inheritance. Molecular-genetic methods enabled access to the non-coding parts of the genome, which in mammals make up more than 90% DNA (deoxyribonucleic acid). MAS (marker assisted selection) or genomic selection showed a better result compared to the conventional method of selection when generally low heritability traits are followed, as is the case with resistance to mastitis. The primary objective in tests concerning appearance of mastitis is the identification of candidate genes that are involved in the immune response of the mammary gland. Lactoferin gene (LTF) is proved by many studies as a valid molecular marker in monitoring the process of resistance to infection of the mammary gland. The aim of this study was to investigate the polymorphism of LTF gene and its impact on the health status of the mammary gland and production characteristics of Holstein-Friesian breed in Serbia. The experiment included 100 cows of different lactation age (1.-4. lactation) on a farm near Belgrade. Due to some health issues that are not directly related to the research 10 cows were excluded. The animals were equally distributed in groups by lactation age (χ2 = 0.578; p = 0.902). DNA was extracted from the blood and intron 6 from lactoferrin gene was amplified by PCR (polymerase chain reaction). Using specific primers, two genotypes AA and AB of the three possible (BB was not found) were identified by PCR-RFLP (PCR-Restriction Fragment Length Polymorphism). In order to examine the health status of the mammary gland and qualitative composition of the total milk production, each month through standard lactation period of 305 days samples were taken from the milk. Somatic cell count (SCC) was determined microscopically and the concentration of protein and fat in milk was determined by spectrophotometry (MilkoScan). The pooled sample of 90 cows showed statistically significant (χ2 = 40.894; p <0.001) representation of the genotype AA (74 or 82.22%) compared to the prevalence of genotype AB (16 or 17.78 %). All genotypes (AA, AB and BB) were in the Hardy-Weinberg equilibrium (P = 0.3547). Distribution of A and B alleles in the observed population were 91.11% and 8.89%, respectively. This high number of homozygotes indicates reduced gene flow in the examined population and a higher degree of genetic conservation..

Analysis of association lactofferin (LTF) gene polymorphism with mammary gland health and production characteristics of Holstein-Friesian cows

Brzi razvoj molekularne genetike tokom posledenje tri decenije omogućio je direktnu analizu genoma životinja, proučavanje strukture i funkcije gena, pa samim tim pomogao boljem razumevanju delovanja nasledne osnove. Molekularno-genetičke metode omogućile su uvid u nekodirajuće delove genoma, koje kod sisara čine više od 90%. DNK (dezoksiribonukleinska kiselina) zapisa. U slučаjevimа gde se prаte osobine koje su generаlno sа niskim heritibilitetom, kаo što je slučаj sа otpornošću nа mаstitis, MAS (mаrker аsistirаnа selekcijа) ili genomskа selekcijа pokаzаle su bolji rezultаt u odnosu nа konvencionаlni metod selekcije. Primаrni cilj u ispitivаnju kаndidаt-genа povezаnih sа pojаvljivаnjem mаstitisа je identifikаcijа genа koji su uključeni u proces imunog odgovorа mlečne žlezde. Laktoferin gen (LTF) se u većem broju istraživanja pominje kao validni molekularni marker u praćenju procesa otpornosti mlečne žlezde prema infekciji. Cilj ovog rada bio je ispitivanje polimorfizma gena za LTF i njegov uticaj na zdravstveni status mlečne žlezde i proizvodne karakteristike krava holštajnfrizijske rase u Srbiji. Ogled je obuhvatao 100 krava različite laktacione starosti (1.-4. laktacija) na farmi blizu Beograda. Životinje su bile ravnomerno raspoređene u grupama po laktacionoj starosti (χ2=0,578; p=0,902). Posle ekstrakcije DNK iz krvi amplifikovan je fragment gena za laktoferin na intronu 6 metodom PCR (polymerase chain reactionreakcija lančane polimeraze). Pomoću specifičnih prajmera, identifikovana su dva genotipa AA i AB od moguća tri, (BB nije identifikovan) metodom PCR-RFLP (Restriction Fragment Lenght Polymorphism-polimorfizam u dužini restrikcionih fragmenata). U cilju ispitivanja zdravstvenog statusa mlečne žlezde, kvalitativnog sastava i ukupne proizvodnje mleka, svakog meseca kroz period standardne laktacije od 305 dana, su uzimani uzorci mleka. Broj somatskih ćelija (SCC) određivan je mikroskopski a koncentracija proteina i mlečne masti utvrđivana je spektrofotometrijski (aparat Milkoscan). U zajedničkom uzorku od 90 krava, konstatovana je statistički vrlo značajno veća (χ2=40,894; p<0,001) zastupljenost genotipa AA ( 74 ili 82,22%) u odnosu na zastupljenost genotipa AB ( 16 ili17,78%). Prema Hardy-Weinberg jednačini odnos genotipova AA, AB i BB se nalazi u ravnoteži (p=0,3547). Distribucija A alela u posmatranoj populaciji bila je 91,11% a B alela 8,89%. Ovako visok broj homozigota ukazuje na smanjeni protok gena u populaciji i veći stepen genetske konzervisanosti zapata. Poizvodne karakteristike praćenih genotipova nisu se statistički razlikovale...The rapid development of molecular genetics during last three decades has facilitate the direct analysis of the genome of animals and insight in gene structure and function, and thus helped to a better understanding basis of genetic inheritance. Molecular-genetic methods enabled access to the non-coding parts of the genome, which in mammals make up more than 90% DNA (deoxyribonucleic acid). MAS (marker assisted selection) or genomic selection showed a better result compared to the conventional method of selection when generally low heritability traits are followed, as is the case with resistance to mastitis. The primary objective in tests concerning appearance of mastitis is the identification of candidate genes that are involved in the immune response of the mammary gland. Lactoferin gene (LTF) is proved by many studies as a valid molecular marker in monitoring the process of resistance to infection of the mammary gland. The aim of this study was to investigate the polymorphism of LTF gene and its impact on the health status of the mammary gland and production characteristics of Holstein-Friesian breed in Serbia. The experiment included 100 cows of different lactation age (1.-4. lactation) on a farm near Belgrade. Due to some health issues that are not directly related to the research 10 cows were excluded. The animals were equally distributed in groups by lactation age (χ2 = 0.578; p = 0.902). DNA was extracted from the blood and intron 6 from lactoferrin gene was amplified by PCR (polymerase chain reaction). Using specific primers, two genotypes AA and AB of the three possible (BB was not found) were identified by PCR-RFLP (PCR-Restriction Fragment Length Polymorphism). In order to examine the health status of the mammary gland and qualitative composition of the total milk production, each month through standard lactation period of 305 days samples were taken from the milk. Somatic cell count (SCC) was determined microscopically and the concentration of protein and fat in milk was determined by spectrophotometry (MilkoScan). The pooled sample of 90 cows showed statistically significant (χ2 = 40.894; p <0.001) representation of the genotype AA (74 or 82.22%) compared to the prevalence of genotype AB (16 or 17.78 %). All genotypes (AA, AB and BB) were in the Hardy-Weinberg equilibrium (P = 0.3547). Distribution of A and B alleles in the observed population were 91.11% and 8.89%, respectively. This high number of homozygotes indicates reduced gene flow in the examined population and a higher degree of genetic conservation..

Analysis of association lactofferin (LTF) gene polymorphism with mammary gland health and production characteristics of Holstein-Friesian cows

Brzi razvoj molekularne genetike tokom posledenje tri decenije omogućio je direktnu analizu genoma životinja, proučavanje strukture i funkcije gena, pa samim tim pomogao boljem razumevanju delovanja nasledne osnove. Molekularno-genetičke metode omogućile su uvid u nekodirajuće delove genoma, koje kod sisara čine više od 90%. DNK (dezoksiribonukleinska kiselina) zapisa. U slučаjevimа gde se prаte osobine koje su generаlno sа niskim heritibilitetom, kаo što je slučаj sа otpornošću nа mаstitis, MAS (mаrker аsistirаnа selekcijа) ili genomskа selekcijа pokаzаle su bolji rezultаt u odnosu nа konvencionаlni metod selekcije. Primаrni cilj u ispitivаnju kаndidаt-genа povezаnih sа pojаvljivаnjem mаstitisа je identifikаcijа genа koji su uključeni u proces imunog odgovorа mlečne žlezde. Laktoferin gen (LTF) se u većem broju istraživanja pominje kao validni molekularni marker u praćenju procesa otpornosti mlečne žlezde prema infekciji. Cilj ovog rada bio je ispitivanje polimorfizma gena za LTF i njegov uticaj na zdravstveni status mlečne žlezde i proizvodne karakteristike krava holštajnfrizijske rase u Srbiji. Ogled je obuhvatao 100 krava različite laktacione starosti (1.-4. laktacija) na farmi blizu Beograda. Životinje su bile ravnomerno raspoređene u grupama po laktacionoj starosti (χ2=0,578; p=0,902). Posle ekstrakcije DNK iz krvi amplifikovan je fragment gena za laktoferin na intronu 6 metodom PCR (polymerase chain reactionreakcija lančane polimeraze). Pomoću specifičnih prajmera, identifikovana su dva genotipa AA i AB od moguća tri, (BB nije identifikovan) metodom PCR-RFLP (Restriction Fragment Lenght Polymorphism-polimorfizam u dužini restrikcionih fragmenata). U cilju ispitivanja zdravstvenog statusa mlečne žlezde, kvalitativnog sastava i ukupne proizvodnje mleka, svakog meseca kroz period standardne laktacije od 305 dana, su uzimani uzorci mleka. Broj somatskih ćelija (SCC) određivan je mikroskopski a koncentracija proteina i mlečne masti utvrđivana je spektrofotometrijski (aparat Milkoscan). U zajedničkom uzorku od 90 krava, konstatovana je statistički vrlo značajno veća (χ2=40,894; p<0,001) zastupljenost genotipa AA ( 74 ili 82,22%) u odnosu na zastupljenost genotipa AB ( 16 ili17,78%). Prema Hardy-Weinberg jednačini odnos genotipova AA, AB i BB se nalazi u ravnoteži (p=0,3547). Distribucija A alela u posmatranoj populaciji bila je 91,11% a B alela 8,89%. Ovako visok broj homozigota ukazuje na smanjeni protok gena u populaciji i veći stepen genetske konzervisanosti zapata. Poizvodne karakteristike praćenih genotipova nisu se statistički razlikovale...The rapid development of molecular genetics during last three decades has facilitate the direct analysis of the genome of animals and insight in gene structure and function, and thus helped to a better understanding basis of genetic inheritance. Molecular-genetic methods enabled access to the non-coding parts of the genome, which in mammals make up more than 90% DNA (deoxyribonucleic acid). MAS (marker assisted selection) or genomic selection showed a better result compared to the conventional method of selection when generally low heritability traits are followed, as is the case with resistance to mastitis. The primary objective in tests concerning appearance of mastitis is the identification of candidate genes that are involved in the immune response of the mammary gland. Lactoferin gene (LTF) is proved by many studies as a valid molecular marker in monitoring the process of resistance to infection of the mammary gland. The aim of this study was to investigate the polymorphism of LTF gene and its impact on the health status of the mammary gland and production characteristics of Holstein-Friesian breed in Serbia. The experiment included 100 cows of different lactation age (1.-4. lactation) on a farm near Belgrade. Due to some health issues that are not directly related to the research 10 cows were excluded. The animals were equally distributed in groups by lactation age (χ2 = 0.578; p = 0.902). DNA was extracted from the blood and intron 6 from lactoferrin gene was amplified by PCR (polymerase chain reaction). Using specific primers, two genotypes AA and AB of the three possible (BB was not found) were identified by PCR-RFLP (PCR-Restriction Fragment Length Polymorphism). In order to examine the health status of the mammary gland and qualitative composition of the total milk production, each month through standard lactation period of 305 days samples were taken from the milk. Somatic cell count (SCC) was determined microscopically and the concentration of protein and fat in milk was determined by spectrophotometry (MilkoScan). The pooled sample of 90 cows showed statistically significant (χ2 = 40.894; p <0.001) representation of the genotype AA (74 or 82.22%) compared to the prevalence of genotype AB (16 or 17.78 %). All genotypes (AA, AB and BB) were in the Hardy-Weinberg equilibrium (P = 0.3547). Distribution of A and B alleles in the observed population were 91.11% and 8.89%, respectively. This high number of homozygotes indicates reduced gene flow in the examined population and a higher degree of genetic conservation..

Zaostala posteljica kod goveda – različiti pristupi terapiji i njihovi efekti

Given the influence of retentio secundinarum (RS) on the reproductive performance of cows, the current work aimed to assess the effect of various approaches to the treatment of retained placenta on the main reproductive parameters, primarily on the interval from parturition to the first service, and the insemination index. The trial involved 120 dairy cows in which the placenta was not expelled within 24 h postpartum. The first group (G1, n=60) contained cows in which the retained placenta was not extirpated, but they were administered antibiotics. The second group (G2, n=60) comprised cows in which the placenta was removed manually, and were also administered antibiotics. At the end of the study, 53 cows remained in G1 and 54 cows in G2. According to medicament therapy, both groups were divided into three sub-groups treated with: procaine benzylpenicillin, chlortetracycline hydrochloride or ceftiofur. Comparison of the performance of G1 and G2 cows showed significantly better fertility parameters occurred in the animals from which the retained placenta was extracted manually. The pregnancy rate in the G2 group was remarkably higher than in the G1 group. The average service interval was significantly lower (p<0.05) in the G2 group compared to the G1 group. The best results were obtained with the i.m. administration of ceftiofur after the removal of the placenta.Uzimajući u obzir uticaj RS (retentio secundinarum) na reproduktivne performanse krava, cilj ovog rada je bio da se proceni efekat različitih pristupa lečenju zadržane posteljice na glavne reproduktivne parametre, pre svega na interval od porođaja do koncepcije i indeks osemenjavanja. U ispitivanju je učestvovalo 120 muznih krava kod kojih nije došlo do izbacivanja posteljice 24 sata nakon porođaja. Prva grupa (G1, n = 60) uključivala je krave kod kojih zadržana placenta nije manuelno uklanjana, već je terapija podrazumevala samo aplikaciju antibiotika. Drugu grupu (G2, n = 60) činile su krave kojima je posteljica odstranjena manuelno i uz to primenjena antibiotska terapija. Do kraja eksperimenta je u prvoj oglednoj grupi ostalo 53 krave, a u drugoj grupi 54 krave. Prema vrsti medikamentozne terapije, obe grupe su podeljene u tri podgrupe i lečene su prokain-benzilpenicilinom, hlortetraciklin hidrohloridom i ceftiofurom. Upoređivanjem reproduktivnih performansi prve i druge grupe krava, primetni su značajno bolji parametri plodnosti kod životinja kojima je manuelno izvađena zadržana posteljica i kojima su uz to aplikovani antibiotici. Broj gravidnih životinja u G2 grupi bio veći u odnosu na G1 grupu. Prosečno trajanje servis perioda bilo je statistički značajno kraće (p<0,05) u G2 grupi u poređenju sa G1 grupom. Najbolji rezultati postignuti su i.m. primenom ceftiofura nakon uklanjanja placente

Intestinal parasitic infections of owned dogs and their importance for one health in the Republic of Serbia

Пси су најпопуларнији кућни љубимци широм света. Близак контакт паса и људи повећава ризик преношења различитих зоонозних паразитских инфекција. С обзиром на значај ветеринарске медицине у очувању концепта Једног здравља, ово истраживање је имало за циљ да се идентификују интестинални паразити који могу имати зоонозни потенцијал и утичу на здравље паса и изврши процена фактора ризика (индивидуални и фактори средине) који условљавају појаву интестиналних паразитских инфекција. Истраживање је спроведено на територији Републике Србије на 382 власничка пса у току 2022. и 2023. године, квалитативним методама копролошке дијагностике са концентрацијом паразитских елемената. Укупна преваленција интестиналних паразита је била 58,7%, а утврђене су протозое: Cystoisospora spp. (9,2%), Sarcocystis spp. (4,5%), Neospora caninum/Hammondia spp. (3,7%), Giardia intestinalis (11,8%); нематоде: Toxocara canis (11,5%), Toxascaris leonina (4,2%), фам. Ancylostomatidae (38,0%), Trichuris vulpis (21,5%), Capillaria spp. (10,5%), трематода Alaria alata (1,6%) и цестоде фамилије Taeniidae (1,3%). Анализом индивидуалних фактора ризика, значајно виша (p<0,05) преваленција интестиналних паразита је утвђена код паса млађих од једне године (83,3%) и код паса старости од једне до пет година (64,4%). Анализом фактора ризика средине, значајно више (p<0,001) преваленцијe су утврђене у категоријама паса који се држе напољу (67,7%) и код паса који се држе у затвореном простору и напољу (72,0%), као и код категорије ловачких паса (81,6%). Додатно, значајно виша (p<0,05) преваленција интестиналних паразита је установљена и у категорији паса који се хране мешовито (72,5%). Резултати овог истраживања сугеришу да је неопходна едукација власника, спровођење редовних паразитолошких прегледа власничких паса и дехелминтизација у складу са налазима добијене копролошке дијагностике.Dogs are the most popular pets worldwide. Close contact between dogs and people increases the risk of transmission of different zoonotic parasitic infections. Given the importance of veterinary medicine in preserving the One Health concept, the aim of this research was to identify the intestinal parasites that may have zoonotic potential and affect the health of dogs and to evaluate the risk factors (individual and environmental factors) that determine the occurrence of intestinal parasitic infections. The research was conducted on the territory of the Republic of Serbia in 2022 and 2023 on 382 owned dogs, using qualitative methods of coprological examination with concentration of parasitic elements. The overall prevalence of intestinal parasites was 58.7%, with detected protozoa: Cystoisospora spp. (9.2%), Sarcocystis spp. (4.5%), Neospora caninum/Hammondia spp. (3.7%), Giardia intestinalis (11.8%); nematoda: Toxocara canis (11.5%), Toxascaris leonina (4.2%), fam. Ancylostomatidae (38.0%), Trichuris vulpis (21,5%), Capillaria spp. (10.5%); trematoda: Alaria alata (1.6%) and cestodes from the Taeniidae family (1.3%). By analyzing the individual risk factors, a significantly higher (p<0.05) prevalence of intestinal parasites was found in dogs younger than one year (83.3%) and in dogs between one and five years old (64.4%). By analyzing the environmental risk factors, a significantly higher (p<0.001) prevalence was found in the dogs that were kept outdoor (67.7%) and indoor/outdoor (72.0%), as well as in the category of hunting dogs (81.6%). Additionally, a significantly higher (p<0.05) prevalence of intestinal parasites was found in the category of dogs fed combined diet (72.5%). Based on the results of coprological diagnostics, this research indicates the importance of educating dog owners, conducting routine parasitological tests on their pets and regular deworming strategies.Zbornik kratkih sadržaj

Synthesis of silicon-based nanoparticles by 10.6 mu m nanosecond CO2 laser ablation in liquid

Silicon-based nanoparticles were produced by irradiating a single-crystal silicon target with 10.6 mu m nanosecond transverse excited atmospheric (TEA) pulsed CO2 laser in de-ionized water. The effects of the laser pulse energies and repetition rate were studied. To reveal the role of thermal effects, a low laser repetition rate has been applied, excluding the interaction of the laser beam with the previously generated cavitation bubble. The analysis of the influence of the laser pulse energies and the laser repetition rate showed that the increase of the laser pulse energies leads to an increase of the nanoparticle size. An explanation of such results was proposed and the importance of the role of the target surface temperature in the ablation process is discussed