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.
Honeybees' gut microbiota can provide new valuable access into the pathogenesis-related factors included in infections. Hence, we researched the presence and comparison of gut microbiota groups in ...control and
spp.-infected honeybee colonies through high-throughput sequencing of the 16S rRNA. As the newest approach in apiary management, we hypothesize that the EM
probiotic for bees could have an important role in therapeutic and immunomodulatory effects on honeybee colonies. The aim of this study was to estimate its impact on the gut microbiota composition of adult honeybees. The major genera were detected, where Lactobacillus was the most abundant genus, followed by Gilliamela, Snodgrassella, and Bifidobacterium. Inoculation with
spp. spores made the relative proportions of Bifidobacterium lower, which was ameliorated by EM
for bees' application. In addition, EM
for bee applied treatments suppressed the increase in the number of
spp. spores. This result points out that continuous EM
for bees treatment shall change bees' gut microbiome composition and mitigate the influence of
spp. infection.
was a major member of the honeybee gut microbiota and may be significantly increased by long-term treatment with EM
for bees. Toward these results, it is possible that EM
for bees treatment will protect honeybees from herbicide glyphosate negative effects in agricultural fields by improving microbiome and immune functions.
Bacillus anthracis, the causative agent of anthrax disease, is a worldwide threat to livestock, wildlife and public health. It is also considered one of the most important pathogens of bioterrorism. ...Rapid and reliable diagnosis and administration of antimicrobials are essential for effective anthrax treatment. In this study, we determined the in vitro susceptibilities of 40 isolates of B. anthracis isolated in Croatia over the recent two decades to 18 antimicrobials. Whole-genome sequencing was performed, and bioinformatics tools were used to determine virulence factors and antimicrobial resistance genes. Core genome-based multilocus sequence typing was used for isolate comparison and phylogenetic analysis. All isolates were susceptible to all antimicrobials recommended for post-exposure prophylaxis or anthrax therapy. Susceptibility was found to all other tested antimicrobials that are an alternative for primary therapy. We found two beta-lactamase genes, but their expression is not sufficient to confer resistance. In all isolates used in this study, we found 21 virulence genes, 8 of which are responsible for toxin and capsule production. As far as phylogenetic analysis is concerned, the B. anthracis isolates from Croatia are categorised into two clades. The first is clade A, subclade Trans Eurasia, and the other is clade B, subclade B2.
Mastitis is one of the most frequent diseases of dairy cows throughout the world, therefore it causes the greatest economic losses in dairy cattle industry. These losses are reflected through: ...reduced milk production, increased costs of medication and the other animal health services, reduced fertility, early culling of animals and the value of discarded milk. Mastitis is also important from the aspects of public health, milk processing and animal welfare. In the pathogenesis of mastitis the key role plays the innate immune response which is the first line of defence against the pathogen invasion of the udder. The innate immune response generates an inflammatory reaction which is the elementary response of an organism to the tissue trauma induced by any physical, chemical or biological causative agent, but primarily it is the protective mechanism of a vital significance which includes increased phagocytic activity, secretion of antimicrobial substances, fibrosis as well as the alterations in tissue structure of affected organ or body cavity. The release of a number of inflammatory mediators as well as reactive oxygen species (ROS) is an important part of inflammatory response. In dairy cows, the metabolic challenge that occurred during the transition from dry period to early lactation may additionally increase the release of ROS which may contribute to development of oxidative stress and inflammatory response. Oxidative stress is defined as a shift in the balance from cellular oxidation-reduction reactions towards oxidation, i.e. to the state of excessive release of oxidants when their removal by antioxidants is impaired and even insufficient. During peripartum period antioxidantive status of dairy cows is seriously impaired and consequently both the oxidative stress and inflammatory response may present the predisposing factors to their higher susceptibility to intramammary infections (IMI) and mastitis. This association between oxidative stress and inflammation during IMI and mastitis indicates their role in the pathogenesis of mastitis. Thus, a better understanding of such a synergism could contribute to development of new approaches to prevention and therapy of IMI and mastitis.
•Laying hens received sulfamonomethoxine (SMM) and trimethoprim (TMP) in two doses.•The distribution of SMM and TMP in egg yolk and white was measured.•SMM and TMP residues was measurable for 30days ...after drug administration.•SMM is detectable for a longer period in egg white (>30days) than in yolk.•TMP is measured in period of 37day in egg yolk but not in white.
The distribution of sulfamonomethoxine (SMM) and trimethoprim (TMP) in egg yolk and white was measured during and after administration of a SMM/TMP combination in laying hens in doses of 8gl−1 and 12gl−1 in drinking water for 7days. The SMM concentration reached maximal levels on day 2 of the post-treatment period for both doses (μgkg−1): 5920 and 9453 in yolk; 4831 and 6050 in white, in doses 1 and 2, respectively. Significant differences in the SMM and TMP concentrations between yolk and white in post treatment period were found. SMM dropped below the LOD (1.9μgkg−1) in yolk after day 16 and 19 for doses 1 and 2. TMP reached maximal levels on day 3 after drug administration for doses 1 and 2 (μgkg−1): 6521 and 7329 in yolk, 1370 and 1539 in white. TMP residues were measured above LOD (0.3μgkg−1) in yolk for both doses on day 37 post-treatment.
Ergot alkaloids (EAs) are mycotoxins produced by several species of fungi of the genus
Claviceps
, among which
Claviceps purpurea
is the most widespread in Europe. This species has been found in many ...economically important cereal grains, such as rye, wheat, triticale, barley, millet and oats. The distribution of EAs contamination has a sporadic incidence with many factors involved in its occurrence, greatly varying between fungal strains, geographic regions, host plants and regional/local weather conditions, at the same time emphasizing that cool, damp weather favours ergot by enhancing the germination of sclerotia. The aim of this study was to investigate the occurrence of ergot sclerotia and EAs in wheat and rye grain samples (n = 64) taken during the year 2021 from Croatian cereal producers located in the Central and Eastern parts of Croatia. In two of the rye samples the presence of ergot sclerotia was detected in the amount of 259 mg/kg and 536 mg/kg, whereas none of the wheat samples tested positive for ergot sclerotia. A higher contamination with EAs was determined in the rye samples (18% contaminated, max 167.4 µg/kg), while a lower frequency of contamination, with only one positive sample (1.9 %), was determined in wheat (68.5 µg/kg). The results pointed to a low-level of EAs contamination of wheat and rye cultivated by Croatian producers during the whole investigative period. However, although a low percentage of the positive tested rye samples with EAs was determined, the content of ergot sclerotia in two of the samples was higher than is allowed by legislation for foodstuffs. Because the levels of these mycotoxins and ergot sclerotia content can vary depending on a number of factors, further research of them is required over a longer period of time and under different cereal cultivation and processing conditions.
Ergot alkaloidi (EA) su mikotoksini koje proizvodi nekoliko vrsta gljivica iz roda
Claviceps
, među kojima je
Claviceps purpurea
najraširenija u Europi. Ova vrsta je pronađena u mnogim ekonomski važnim žitaricama, kao što su raž, pšenica, tritikal, ječam, proso i zob. Distribucija kontaminacije EA ima sporadičnu pojavu, s mnogo čimbenika koji su uključeni u njihovu pojavu, uvelike varirajući između sojeva gljivica, geografskih regija, biljaka domaćina i regionalnog vremena, što ukazuje da hladno i vlažno vrijeme pogoduje ergotu tako što potiče klijanje sklerocija. Cilj ovog istraživanja bio je istražiti pojavu ergot sklerocija i EA u uzorcima pšenice i raži (
n
=64) uzetim tijekom 2021. godine od hrvatskih proizvođača žitarica u središnjoj i istočnoj Hrvatskoj. U dva uzorka raži utvrđena je prisutnost ergot sklerocija u količini od 259 mg/kg i 536 mg/kg. U niti jednom uzorku pšenice nije pronađen ergot sklerocij. Veća kontaminacija sa EA utvrđena je u uzorcima raži (18 % kontaminirano, max 167,4 µg/kg), dok je manja učestalost kontaminacije, sa samo jednim pozitivnim uzorkom (1,9 %), utvrđena u pšenici (68,5 µg/kg). Rezultati su ukazali na nisku razinu kontaminacije sa EA pšenice i raži koje su uzgojili hrvatski proizvođači tijekom cijelog istraživanog razdoblja. Međutim, iako je utvrđen nizak postotak pozitivno testiranih uzoraka raži na EA, sadržaj ergot sklerocija u dva uzorka bio je veći nego što je to zakonodavstvom dopušteno za hranu. Budući da razine tih mikotoksina i ergot sklerocija mogu varirati ovisno o brojnim čimbenicima, potrebno je njihovo daljnje istraživanje tijekom dužeg vremenskog razdoblja i pod različitim uvjetima uzgoja i obrade žitarica.
Raw cow, goat and sheep milk samples were collected in different regions of Croatia during spring and autumn 2016. Aflatoxin M1 (AFM1) concentrations were measured in the following ranges (ng/kg): ...cow milk 0.93-85.4; goat milk 2.0-18.6; sheep milk 2.27-11.2. AFM1 levels exceeding the European Union maximum residue levels of 50 ng/kg were found in two cow milk samples in spring and 10 cow milk samples in autumn. The probable daily intakes (PDIs) for all three dairy species were from 0.0108 to 0.0165 ng/kg b.w./day and contributing 1.08-1.65% to the proposed provisional maximum tolerable daily intake (PMTDI; 1 ng/kg b.w./day), indicating low risk exposure for consumers. The mean positive cow milk PDI was 0.15 ng/kg b.w./day, contributing 15.2% to the PMTDI.
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.
Importance of systematic mastitis control in dairy herds is described through the presentation of data concerning mastitis occurrence and mastitis significance in modern milk production. The research ...was carried out by farm visits and by taking quarter samples from all lactating cows at the time of visit. Samples were taken before evening milking. Each quarter sample was tested by Zagreb mastitis test (ZMT). Furthermore, each sample was examined bacteriologically by inoculation on aesculin blood agar. Identification of grown colonies was carried out using internationally accepted methodology. Obtained results were statistically analyzed using Stata 13.1 statistical package. Quarter samples from 385 cows were analyzed. ZMT -positive reactions were noticed in 13.7% of all quarters. Mastitis pathogens were isolated from 175 (13%) of quarter samples. 145 out of 385 cows (37.3%) included in research had at least one ZMT positive quarter or permanently lost (dried off) quarter. From 106 out of 363 cows (29.8%) with all four functional quarters some of mastitis pathogens were isolated. The most frequently isolated pathogens were Staphylococcus aureus, streptococci, Trueperella (Arcanobacterium) pyogenes and Corynebacterium bovis. There was no statistical difference in mastitis occurrence between front and rear mammary quarters. ZMT results and microbiological examination were moderately correlated (Kappa index = 0.4662).
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