The bacterial species
is the most common causative agent of mastitis in cows in most countries with a dairy industry. The prevalence of infection caused by
ranges from 2% to more than 50%, and it ...causes 10-12% of all cases of clinical mastitis.
The objective was to analyze 237 strains of
isolated from the milk of cows with subclinical mastitis regarding the
,
and
genes and to perform
and multi-locus sequence typing (MLST).
Sequencing amplified gene sequences was conducted at Macrogen Europe. Ridom StaphType and BioNumerics software was used to analyze obtained sequences of
and seven housekeeping genes.
The
fragment was present in 204 (86.1%) of strains, while
and
gene were detected in 10 strains, and the
gene was not detected.
typing successfully analyzed 153 tested isolates (64.3%), confirming 53
types, four of which were new types. The most frequent
type was t2678 (14%). MLST typed 198 (83.5%) tested strains and defined 32 different allele profiles, of which three were new. The most frequent allele profile was ST133 (20.7%). Six groups (G) and 15 singletons were defined.
Taking the number of confirmed
types and sequence types (STs) into account, it can be concluded that the strains of
isolated from the milk of cows with subclinical mastitis form a heterogenous group. To check the possible zoonotic potential of isolates it would be necessary to test the persons and other livestock on the farms.
The binding of alkali metal cations with two tertiary-amide lower-rim calix4arenes was studied in methanol,
-dimethylformamide, and acetonitrile in order to explore the role of triazole and glucose ...functionalities in the coordination reactions. The standard thermodynamic complexation parameters were determined microcalorimetrically and spectrophotometrically. On the basis of receptor dissolution enthalpies and the literature data, the enthalpies for transfer of reactants and products between the solvents were calculated. The solvent inclusion within a calixarene hydrophobic
was explored by means of
H NMR spectroscopy. Classical molecular dynamics of the calixarene ligands and their complexes were carried out as well. The affinity of receptors for cations in methanol and
-dimethylformamide was quite similar, irrespective of whether they contained glucose subunits or not. This indicated that sugar moieties did not participate or influence the cation binding. All studied reactions were enthalpically controlled. The peak affinity of receptors for sodium cation was noticed in all complexation media. The complex stabilities were the highest in acetonitrile, followed by methanol and
-dimethylformamide. The solubilities of receptors were greatly affected by the presence of sugar subunits. The medium effect on the affinities of calixarene derivatives towards cations was thoroughly discussed regarding the structural properties and solvation abilities of the investigated solvents.
Brucellosis in swine was surveyed from 2011 to 2015 in 13 counties in Croatia. A total of 3230 breeding males were tested serologically, and positive reactions were confirmed in 42 (1.3%) males from ...17 farms. A total of 641 sows with abortion or reproductive problems were tested, and positive reactions were confirmed in 34 (5.3%). Organs from 68 swine were tested for bacteria, and Brucella spp. was isolated from 47 (69.1%). B. suis was identified in 45 isolates from domestic swine and 2 isolates from wild boar in six counties in Croatia, and all isolates were found to be B. suis biovar 2 based on Bru-up/Bru-low, Bruce-ladder, Suis-ladder and RFLP-based PCR assays. These results indicate that brucellosis is difficult to eradicate in free-range and semi-free-range swine farming, particularly in areas where contact with wild boar is possible. Further disease control measures are required.Key words: Brucella suis biovar 2; swine; abortion; prevalence; CroatiaBRUCELOZA PRAŠIČEV, POVZROČENA Z BAKTERIJO Brucella suis BIOVAR 2 NA HRVAŠKEMBrucelozo pri prašičih smo spremljali od leta 2011 do leta 2015 v 13 hrvaških občinah. S serološko analizo smo preverili prisotnost bruceloze pri 3230 samcih v razplodu. Pozitivne reakcije smo ugotovili pri skupno 42 merjascih s 17 farm, kar predstavlja 1,3 % živali. S serološkimi testi smo preverili prisotnost protiteles proti bruceli tudi pri 641 plemenskih svinjah, ki so zvrgle ali imele težave z zabrejitvijo. Pozitivna reakcija je bila ugotovljena pri 34 svinjah, kar predstavlja 5,3 % vseh testiranih živali. Notranje organe 68 svinj iz šestih občin smo uporabili za osamitev bakterij Brucella spp. Bakterije smo ugotovili pri 47 vzorcih (69,1 %). Bakterijo Brucella suis smo odkrili v vseh 47 vzorcih, izmed katerih jih je bilo 45 od domačih plemenskih svinj, dva vzorca pa sta bila od divjih svinj. Vse izolirane bakterije so pripadale sevu B. suis biovar 2, kot so pokazale dodatne analize z uporabo metod Bruup/Bru-low, Bruce-ladder, Suis-ladder in RFLP. Ti rezultati kažejo, da je popolno izkoreninjenje bruceloze težavno, še posebej v prostih rejah prašičev, kjer obstajajo možnosti stika z divjimi prašiči. Zato bi bilo v prihodnje potrebno razmisliti o dodatnih načinih nadzora nad to nevarno boleznijo prašičev.Ključne besede: Brucella suis biovar 2; prašiči; zvrg; pojavnost; Hrvaška
Despite the growing importance of solid-state reactions, their thermodynamic characterization has largely remained unexplored. This is in part due to the lack of methodology for measuring the heat ...effects related to reactions between solid reactants. We address here this gap and report on the first direct thermodynamic study of chemical reactions between solid reactants by isothermal calorimetry. Three reaction classes, cationic host-guest complex formation, molecular co-crystallization, and Baeyer-Villiger oxidation were investigated, showcasing the versatility of the devised methodology to provide detailed insight into the enthalpy changes related to various reactions. The reliability of the method was confirmed by correlation with the values obtained
via
solution calorimetry using Hess's law. The thermodynamic characterization of solid-state reactions described here will enable a deeper understanding of the factors governing solid-state processes.
Methodology for direct measurement of reaction enthalpy by isothermal calorimetry has been developed and applied for various reactions in solid state.
The medium effect on the complexation of alkali metal cations with a calix4arene ketone derivative (L) was systematically examined in methanol, ethanol, N-methylformamide, N,N-dimethylformamide, ...dimethyl sulfoxide, and acetonitrile. In all solvents the binding of Na+ cation by L was rather efficient, whereas the complexation of other alkali metal cations was observed only in methanol and acetonitrile. Complexation reactions were enthalpically controlled, while ligand dissolution was endothermic in all cases. A notable influence of the solvent on NaL + complex stability could be mainly attributed to the differences in complexation entropies. The higher NaL + stability in comparison to complexes with other alkali metal cations in acetonitrile was predominantly due to a more favorable complexation enthalpy. The 1H NMR investigations revealed a relatively low affinity of the calixarene sodium complex for inclusion of the solvent molecule in the calixarene hydrophobic cavity, with the exception of acetonitrile. Differences in complex stabilities in the explored solvents, apart from N,N-dimethylformamide and acetonitrile, could be mostly explained by taking into account solely the cation and complex solvation. A considerable solvent effect on the complexation equilibria was proven to be due to an interesting interplay between the transfer enthalpies and entropies of the reactants and the complexes formed.
Canine respiratory coronavirus is a relatively new addition to the list of pathogens causing canine infectious disease complex. The virus is highly contagious, with a high prevalence in the dog ...population worldwide, especially in shelters. This study aimed to establish the presence and risk factors associated with infection in privately owned dogs and breeding colonies. This study was the first to demonstrate the presence of canine respiratory coronavirus in Croatia. Out of the 257 serum samples, 35.03% of dogs from breeding kennels and 43% of pet dogs tested enzyme-linked immunoassay positive, but the difference was not statistically significant. Sex was not an important risk factor, but the seropositivity rate increased with age. Mixing of dogs during hunting, training and dog shows was not associated with a higher seroprevalence in the breeding colonies. Daily cleaning and disinfection showed little effect on the infection spread. The study was done on a limited sample. However, it still provides evidence that the epizootiology of this disease is complex. There is no available vaccine for canine respiratory coronavirus, and further studies on environmental and risk factors will give the valuable data needed to prevent this disease. Keywords: canine respiratory coronavirus; seroprevalence; breeding colonies; ELISA; Croatia Pseci respiratorni koronavirus nedavno je dodan na listu patogena koji uzrokuju zarazni kašalj legla. Zbog svoje izrazite kontagioznosti proširio se diljem svijeta, a osobito je cest u pasa u skloništima za nezbrinute životinje. Osnovni je cilj ovog istraživanja bio ispitati proširenost infekcije u pasa u privatnom vlasništvu i uzgajivacnicama te ustanoviti cimbenike rizika koji pogoduju infekciji. Ovo je bilo prvo istraživanje koje je dokazalo prisutnost pseceg respiratornog koronavirusa u Hrvatskoj. Od 257 pretraženih uzoraka seruma 35,03% uzoraka pasa privatnih vlasnika i 43% uzoraka pasa iz uzgajivacnica dalo je pozitivan rezultat imunoenzimnog testa. Važno je napomenuti da razlika u seroprevalenciji izmedu ovih dviju populacije nije bila statisticki znakovita. Spol takoder nije bio znakovit cimbenik rizika, ali je seroprevalencija rasla s porastom dobi životinja. Miješanje životinja iz razlicitih uzgoja, prilikom lova, dresure ili izložbi pasa, nije dovelo do porasta seroprevalencije u uzgajivacnicama. Ni provodenje dnevne dezinfekcije nije znakovito utjecalo na seroprevalenciju. Ovo je istraživanje provedeno na ogranicenom broju uzoraka, ali ipak dokazuje složenost epizootiologije infekcije psecim respiratornim koronavirusom. Kako cjepivo još uvijek nije dostupno, dodatna istraživanja cimbenika okoliša i domacina, važnih za epizootiologiju ove bolesti, dat ce važne podatke nužne za provodenje mjera prevencije. Kljucne rijeci: pseci respiratorni koronavirus; seroprevalencija; uzgajivacnice; ELISA; Hrvatska
Pathogenic streptococci are implicated in clinical and subclinical mastitis. Most laboratories identify streptococci on the basis of microbiological examination, but molecular diagnostic methods have ...become the gold standard of mastitis diagnosis in the last few years. Therefore, this study aims to determine the agreement of microbiological and molecular identification of streptococci isolates from bovine milk. Milk samples were taken before the evening milking into sterile tubes. Samples were examined bacteriologically by inoculation on aesculin blood agar. Identification of grown colonies was carried out using internationally accepted methodology. Sequencing of the 16S rRNA gene was the reference method used to confirm Streptococcus sp. in all bacterial isolates. In the study, 54 strains of bacteria isolated from milk samples from the udder quarters of dairy cows with subclinical mastitis were examined using molecular methods. By conventional microbiological examination, the strains were identified to the species (Strep. agalactiae, Strep. dysgalactiae and Strep. uberis) or the genus level (Streptococcus spp.) without final identification of the species. On the basis of 16S rRNA analysis, 47 out of 54 examined streptococcal strains were found to belong to the genus Streptococcus sp. Among the streptococci identified, 6 isolates belonged to Strep. agalactiae, ¸8 isolates to Strep. dysgalactiae, 2 isolates to Strep. canis and 31 isolates belonged to Strep. uberis. Among the seven remaining isolates, three were identified as Enterococcus faecalis and four as Lactococcus lactis. Agreement between the identification procedures used was fair, with a Kappa index of 0.2181 (SE=0.0612; Z=3.56; p=0.0002).
Background: Klebsiella pneumoniae is a bacterial species that often causes infections in humans. Infections occur most frequently in hospitalised or immunocompromised patients and are treated with ...antimicrobials. In recent decades, K. pneumoniae has developed significant resistance to many antimicrobials. Objective: The main goal of this study was to determine the frequency of resistance of isolated K. pneumoniae strains from urine samples of hospital patients and outpatients, and to find evidence of ESBL strains and their resistance to certain antibiotics. Methods: During the study period, Klebsiella pneumonia was isolated from the urine samples of 430 patients. The procedure for processing of urine samples, identification, susceptibility toward antimicrobials and evidence of ESBL strains were carried out according to the recommended standards. Results: Of the total K. pneumoniae isolates, 153 (35.6%) were isolated from hospital patients and 277 (64.4%) from outpatients. Strains isolated from hospital patients were resistant to each tested antibiotic. ESBL strains were detected in 169 (39.30%) samples, 92 (60.13%) from hospital patients and 77 (27.8%) from outpatients. Conclusion: Strains of K. pneumoniae isolated from the urine of hospital patients and outpatients have developed significant resistance against all tested antibiotic substances. A higher occurrence of ESBL strains was observed in hospital patients than in outpatients. ESBL strains were resistant to all penicillins and almost all cephalosporins. Highly effective antimicrobials were amikacin, colistine, carbapenem and fosfomycin. The best therapeutic results were achieved when patients were treated with fosfomycin and imipenem.
Mastitis je upalna reakcija organizma na infekciju sekretornog dijela mliječne žlijezde. Uzročnici mastitisa dijele se bojanjem po Gramu na Gram-pozitivne i Gramnegativne; prema etiologiji na ...kontagiozne i uvjetovane uzročnike. Kontagiozni se uzročnici najčešće prenose tijekom mužnje i prouzroče dugotrajne, kronične mastitise, uglavnom subkliničkog tijeka. Za razliku od njih, uvjetovani uzročnici u pravilu izazivaju kratkotrajne infekcije, ali s češćim kliničkim manifestacijama. Inficirane se krave 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 u procjeni broja somatskih stanica koji se provodi u terenskim uvjetima. Somatske stanice čine epitelne stanice i leukociti. Nalaze se u mlijeku, ali se njihov broj i odnos mijenja ovisno o upalnim promjenama u mliječnoj žlijezdi. Kretanje broja somatskih stanica uglavnom ovisi o pojavi mastitisa, ali i o stadiju laktacije, životnoj dobi životinje, godišnjem dobu, ali i ostalim bolestima mliječne krave. Mlijeko s povećanim brojem somatskih stanica ima promijenjenu kakvoću. Mlijeko sadrži niži udio mliječne masti i laktoze, a povećan je i udio proteina i električna provodljivost zbog povišene koncentracija klora i natrija u mlijeku. Osim toga, mlijeko ima i 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 proizvedenih od takvog mlijeka zbog zadržavanja veće količine vode je smanjen. Pravilnim i redovitim provođenjem postupaka dezinfekcije sisa vimena prije i poslije mužnje poboljšava se prinos i kakvoća mlijeka, odnosno smanjuju se troškovi liječenja mastitisa, a povećava se i prihod farme.
Mastitis is an inflammatory reaction 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 aetiology into contagious and environmental causes. Contagious pathogens are most transmitted during milking, and cause long-lasting, chronic mastitis with a 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 reached through indirect or direct methods of determining the somatic Cell count and by conducting bacteriological examination of milk. The Zagreb mastitis test is a quick and simple orientation method for estimating the number of somatic cells. Its advantage is that can be 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 somatic cell count can change depending on the occurrence of mastitis, but also on the stage of lactation, animal age, 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 a 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 or 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 associated with mastitis treatment, thereby increasing both milk quality and farm revenues.
Over a year into the COVID-19 pandemic, there is growing evidence that SARS-CoV-2 infections among dogs are more common than previously thought. In this study, the prevalence of SARS-CoV-2 antibodies ...was investigated in two dog populations. The first group was comprised of 1069 dogs admitted to the Veterinary Teaching Hospital for any given reason. The second group included dogs that shared households with confirmed COVID-19 cases in humans. This study group numbered 78 dogs. In COVID-19 infected households, 43.9% tested ELISA positive, and neutralising antibodies were detected in 25.64% of dogs. Those data are comparable with the secondary attack rate in the human population. With 14.69% of dogs in the general population testing ELISA positive, there was a surge of SARS-CoV-2 infections within the dog population amid the second wave of the pandemic. Noticeably seroprevalence of SARS-CoV-2 in the dog and the human population did not differ at the end of the study period. Male sex, breed and age were identified as significant risk factors. This study gives strong evidence that while acute dog infections are mostly asymptomatic, they can pose a significant risk to dog health. Due to the retrospective nature of this study, samples for viral isolation and PCR were unavailable. Still, seropositive dogs had a 1.97 times greater risk for developing central nervous symptoms.
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