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Objectives: Antimicrobial drugs are frequently administered in veal calves, but investigations on associations with antimicrobial susceptibility of bacteria are scarce and convey partly contradictory findings. The aim of this study was to investigate associations of antimicrobial use (AMU) during the fattening period with antimicrobial susceptibility shortly before slaughter.Methods: Detailed treatment data of 1905 veal calves from 38 farms were collected prospectively during monthly farm visits for 1 year (n = 1864 treatments, n = 535 visits); 1582 Escherichia coli, 1059 Pasteurella multocida and 315 Mannheimia haemolytica were isolated from rectal and nasopharyngeal swabs collected before slaughter and subjected to antimicrobial susceptibility testing by microdilution. Associations of antimicrobial treatments with resistant isolates were investigated at the calf level.Results: Associations of AMU with antimicrobial resistance were observed using generalized linear models. For E. coli, the odds of being resistant were increased with increased AMU (OR 1.36 when number of treatments >1, P = 0.066). Use of tetracyclines was associated with resistance to tetracycline (OR 1.86, P < 0.001) and use of penicillins was associated with resistance to ampicillin (OR 1.66, P = 0.014). No significant associations were observed for P. multocida (use of aminoglycosides: OR 3.66 for resistance to spectinomycin, P = 0.074). For M. haemolytica, the odds of being resistant were increased with increased AMU (OR 4.63, P < 0.001), and use of tetracyclines was associated with resistance to tetracycline (OR 6.49, P < 0.001).Conclusions: Occurrence of resistant bacteria shortly before slaughter was associated with AMU in veal calves. Prudent and appropriate use may contribute to limit the selection of resistant bacteria on veal farms. [ABSTRACT FROM AUTHOR]

Bovine brucellosis caused by the organism Brucella abortus is a chronic infectious disease of public health and economic significance. Studies on prevalence of bovine brucellosis in Abia State are scarce. Therefore, a cross-sectional study was conducted to determine the prevalence of bovine brucellosis in the State. Blood samples were collected from 212 cattle from various parts of the State and sera subjected to Rose Bengal Plate Test (RBPT) to detect antibodies against Brucella. Overall sero-prevalence of 13.7% was reported. The prevalence was higher in female cattle (24.2%) than in males (11%). Red Bororo showed higher seropositivity (26.7%) than other breeds screened. Sero-prevalence was higher in the semi-intensively managed animals (27.8%) than in extensively reared cattle. Similarly, cattle aged 2 to 3 years recorded a higher prevalence (25%) than others. However, there was no statistically significant association between the seroprevalence of brucellosis and sex (P= 0.05), age (P=0.82), breed (P=0.25), and management system (P=0.07 ). The detection of brucellosis in cattle poses a very significant public health risk in Abia state, and so it is important to carry out awareness campaigns to enlighten cattle handlers and the general public of its public health significance. [ABSTRACT FROM AUTHOR]

Toxoplasma gondii is the agent of toxoplasmosis, which is common to both humans and cattle. That is why the goal of work was to study the spreading of the agent of toxoplasmosis among cattle in certain regions of Ukraine, which in turn will make it possible to predict the appearance of the disease among people and prevent the development of its clinical signs. Whole blood or serum samples of cattle of different ages and sexes from farms in Kyiv, Zhytomyr, Khmelnytskyi and Lviv regions of Ukraine were sent to the laboratory for research. The presence of total antibodies to T. gondii was determined in the serum of the animals. To do this, we used the method of enzyme-linked immunosorbent assay using test kits from different manufacturers in accordance with the guidelines. In general, the prevalence of T. gondii among cattle in Kyiv, Zhytomyr, Khmelnytskyi and Lviv regions of Ukraine according to the results of studies was 10.3% (95% confidence interval: 6.7-15.1). At the same time, the study of animals was carried out in two stages, in 2014 and 2018, and the prevalence did not differ significantly. Thus, in 2014, according to the results of research, a positive reaction to the agent of toxoplasmosis was detected in 10 samples or 13.9% (95% confidence interval: 7.3-23.4), while in 2018 this figure was 11 samples or 8.4% (95% confidence interval: 4.5-14.1) of the studied animals. Also, in 2014 and 2018 studies found that the highest level of seroprevalence of the agent of toxoplasmosis in both years of research was registered in cattle from farms of Zhytomyr and Kyiv regions was 11.9% (95% confidence interval: 4.5-24.4) and 11% (95% confidence interval: 5.9-18.3), respectively. During the conducted research, an increase in the prevalence of T. gondii with the age of animals was statistically significant. Among animals under six months of age, of the 65 serum samples tested, 3 tested positively to the agent (4.6; 95% confidence interval: 1.2-12.1), while in the group of animals older than three years (49 cows) 10 samples were positively responded (20.4; 95% confidence interval: 10.9-33.4) compared to the previous group of animals, the P-value was 0.0114. So, the data obtained indicate the presence of the agent of toxoplasmosis among cattle in Ukraine, which requires further study and development of approaches to prevent human infection when eating meat and dairy products of positively reacting animals [ABSTRACT FROM AUTHOR]

Aim: Cattle is one of the main sources of food supply chain for humans in most countries. The present study aimed to identify the infection rates for Toxoplasma gondii, Neospora caninum, and Sarcocystis spp. by polymerase chain reaction (PCR) method in native slaughtered cattle in Kashan, central Iran. Materials and Methods: Totally, 159 diaphragm, esophagus, and muscle samples (53 samples of each) were collected from native beef cattle from Kashan slaughterhouse, central Iran. The genomic DNA was extracted, and PCR method was used separately for detection of N. caninum, Sarcocystis, and T. gondii species using specific primers. Finding: Sarcocystis was found in 84.9% of muscles, 83% of esophagus, and 84.9% of diaphragm samples. Mixed infection (Sarcocystis cruzi–Sarcocystis hominis) was the most common infection, followed by S. cruzi and S. hominis. Sarcocystis hirsuta was not detected in any samples. T. gondii was detected only in three (5.7%) out of the 53 muscle tissues samples of cattle. N. caninum was found in 18.9% of muscles, 24.5% of esophagus, and 28.3% of diaphragm samples. One of the cattle had coinfection to Neospora, Toxoplasma, and Sarcocystis in muscles simultaneously. There was no statistically significant difference between infection rates and age as well as sex in each organ. Conclusion: This study revealed a low prevalence rate of T. gondii, but a high prevalence of infection to N. caninum and S. cruzi or mixed infection of S. cruzi with S. hominis among slaughtered cattle. Prevention measures such as keeping away dogs from cattle grazing are recommended. [ABSTRACT FROM AUTHOR]

Species of the genus Sarcocystis are recognized as protozoan parasites infecting a wide range of animals, including humans. This study aimed to provide data on the occurrence, genetic characterization, and epidemiological significance of Sarcocystis spp. in cattle destined for human consumption in Romania. A total of 117 heart samples from slaughtered cattle in three southwestern Romanian counties (Dolj, Timiș, and Gorj) were analyzed in order to detect sarcocysts, using fresh examination microscopic techniques. Subsequently, the isolated sarcocysts and/or cyst fragments (5–15 per sample) from each infected animal were molecularly characterized. Overall, 17.9% (21/117) of the tested animals were found to be Sarcocystis spp. positive by microscopy. Genetic characterization of Sarcocystis spp. isolates, based on sequence analysis of the 18S rRNA gene, showed the presence of a single species, namely S. cruzi. No correlation was found (p>0.05) between S. cruzi infection and the origin, age, breed, and gender of cattle, but the grazing farming system was positively associated (p=0.031) with the pathogen prevalence and can be considered a risk factor (OR = 3.6) in acquiring infection. To evaluate the possible public health risk, further investigation focused on the processing of other Sarcocystis-specific tissue matrices and evidence of human infections is recommended. This is the first study of bovine Sarcocystis infection in Romania. [ABSTRACT FROM AUTHOR]

Objectives: To explore the dynamics of faecal ESBL/AmpC shedding in dairy cattle and farmers, a study was conducted to examine changes in shedding by individual animals, as well as environmental exposure, and to study the association between antimicrobial use (AMU) and ESBL/AmpC shedding.Methods: The study comprised a cross-sectional survey of 20 farms and a 1 year follow-up of 10 farms. Faecal samples were cultured by both direct inoculation on MacConkey agar + 1 mg/L cefotaxime (MC+) and enrichment in LB-broth + 1 mg/L cefotaxime with subsequent inoculation on MC+. Dust samples were collected using electrostatic dustfall collectors (EDCs). Human faecal samples were collected by the farmers. Presence of ESBL/AmpC genes was screened for by PCR and sequencing. Using mixed effects logistic regression, ORs were determined and population-attributable fractions (PAFs) calculated subsequently.Results: In Phase 1, 8/20 farms were positive for ESBL/AmpC and, with 2 negative farms, were selected for Phase 2. Transient shedding of dominant allele variants was observed in the animals. EDCs and human faecal samples did not reflect what was observed in the animals. AMU was related to shedding of ESBLs in the next sampling moment [OR 14.6 (95% CI 3.0-80.0)] and the PAF of AMU was 0.36 (95% CI 0.08-0.77). Calves fed with colostrum from cows on dry-off therapy was not a risk factor [OR 1.7 (95% CI 0.7-4.9, P = 0.28)].Conclusions: The presence of ESBL/AmpC could only be partly explained by AMU. No link was shown between shedding in cattle and humans or the environment. Interventions should focus on prevention of introduction. [ABSTRACT FROM AUTHOR]

Background: There are few data on the epidemiology of infections caused by Streptococcus bovis (Sb). Some studies suggest that both residence in rural areas and contact with livestock could be potential risk factors. Methods: We performed a retrospective study for the period 2005–2016 of all cases of bacteremia caused by Sb in Galicia (a region in the northwest of Spain). The association between the incidence rate of Sb bacteremia and the number of cattle by province and district was analyzed. Results: 677 cases were included with a median age of 76 years, 69.3% males. The most frequent infections were endocarditis (234 cases, 34.5%), primary bacteremia (213 cases, 31.5%) and biliary infection (119 cases, 17.5%). In 252 patients, colon neoplasms were detected (37.2%). S. gallolyticus subsp. gallolyticus was the predominant species (52.3%). Mortality was 15.5% (105 cases). The annual incidence rate was 20.2 cases/106 inhabitants and was correlated with the density of cattle (p < 0.001), but not with rurality. When comparing the two provinces with a strong predominance of rural population, but with important differences in the number of cattle, such as Orense and Lugo, with 6% and 47.7% of Galician cattle, respectively, the rates were very different: 15.8 and 43.6 cases/106, respectively, with an RR of 2.7 (95% CI, 2.08–3.71). Some districts of the province of Lugo had rates higher than 100 cases/106 inhabitants. Conclusions: Our study shows a significant correlation between the rates of Sb bacteremia and cattle density, suggesting a possible transmission of Sb from cows to people. [ABSTRACT FROM AUTHOR]

Disease incidence is intimately associated with an animal's commensal bacteria populations (microbiome), as microbes that are involved with morbidity and mortality are commonly found in animals with no sign of disease. An understanding of the animal's resident respiratory pathogens, in the upper nasal cavity prior to weaning, may help us to understand the impact of these pathogens on incidence of respiratory disease. For this research, the overall goal was to characterize bacterial populations associated with calves at an early age and through time periods prior to weaning in 3 herds at the U.S. Meat Animal Research Center. Nasal swabs from the upper nasal cavity were collected at initial vaccination (approximately 40 d of age), preconditioning (approximately 130 d of age), and weaning (approximately 150 d of age) in 2015 and 2016. DNA was extracted from nasal swabs and combined into 2 pools of 10 animals for each sampling time point, in each herd, for a total of 6 pools at each sampling time point and 18 pools for all sampling time points within each year. To evaluate and compare the microbiome of each pooled sample, hypervariable regions 1 through 3 along the 16S ribosomal RNA (rRNA) gene were amplified by PCR and sequenced using next-generation sequencing (Illumina MiSeq) for identification of the bacterial taxa present. Alpha and beta diversity were also measured. Overall, microbial communities were different between combinations of sampling year, herd location, and sampling time prior to weaning as shown by beta diversity. Analysis of these specific respiratory pathogens prior to weaning will present a clearer picture of the distribution of microbial populations in animals prior to weaning and not exhibiting clinical signs of respiratory disease. Therefore, evaluation of the animal's resident bacterial populations in the upper nasal cavity during different phases of the beef production system may help us to understand the impact of the microbiome on incidence of respiratory disease in cattle. [ABSTRACT FROM AUTHOR]

This study aimed to molecular investigation the prevalence of Theileriaannulataparasite that isolated from blood samples of cattle. A hundred of blood sampleswascollected randomanly from cattles ofthe middle area of Iraq (Babylon province). Samples were submitted to blood DNA extraction assay. Nano drop spectrophotometer and QRT-PCR with TaqMan methods were involved for the surface antigen Tams1detection of Theileriaannulata. Real- Time PCR results showed only 16 samples were positive out of 50 blood samples with a percentage 32%. The threshold cycle (CT value) of these positive samples were ranged from CT: 24.29 to CT: 35.69. The Real-Time PCRefficiency was validated using standard curve method, and the efficiently was approximately (99.9%).Surprisingly, the overall results from current study showed there were no association between ages, gender. Infectionsdistribution between (1-12month) (28.57%), 1-2 year (31.57%) and 3-10 year (29.4%).Additionally, the ratio of the infected females at age of 1-2yearswere twice more than the ratio of infected males. [ABSTRACT FROM AUTHOR]

Natural transference of maternal microbes to the neonate, especially at birth via the vaginal canal, has recently been recognized in humans and cows; however, its microbial influence on calf health has not yet been documented. We compared the bacterial communities in vaginal and fecal samples from 81 pregnant dairy cows versus those in nasopharyngeal and fecal samples collected at 3, 14 and 35 days of life from their respective progeny. The microbiota of the calf upper respiratory tract (URT), regardless of calf age, was found to be highly similar to the maternal vaginal microbiota. Calf fecal microbiota clustered closely to the maternal fecal microbiota, progressing toward an adult-like state over the first 35 days when relative abundances of taxa were considered. Sixty-four, 65 and 87% of the detected OTUs were shared between cow and calf fecal microbiota at days 3, 14 and 35 respectively, whereas 73, 76 and 87% were shared between maternal vaginal microbiome and calf URT microbiota at days 3, 14 and 35, respectively. Bacteroidetes, Ruminococcus, Clostridium, and Blautia were the top four genera identified in maternal and calf fecal samples. Mannheimia, Moraxella, Bacteroides, Streptococcus and Pseudomonas were the top five genera identified in maternal vaginal and calf URT samples. Mannheimia was relatively more abundant in the vaginal microbiota of cows whose progeny were diagnosed with respiratory and middle ear disease. Our results indicate that maternal vaginal microbiota potentially influences the initial bacterial colonization of the calf URT, and that might have an important impact on the health of the calf respiratory tract and middle ear. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the effects of saponins on the rumen microbiota and the ruminal metabolome. Alfalfa hay (AH) and soybean hulls (SH) were used as fiber sources for the control diets. The AH and SH diets were supplemented with tea saponins resulting in two additional diets named AHS and SHS, respectively. These 4 diets were fed to 24 young male Holstein cattle (n = 6 per diet). After 28 days of feeding, the rumen fluid from these cattle was collected using an oral stomach tube. Illumina MiSeq sequencing and ultrahigh-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF/MS) were used to investigate the changes in the ruminal microbes and their metabolites. The relative abundance of Prevotellaceae_YAB2003 increased, while Ruminococcaceae_NK4A214 and Lachnospiraceae_NK3A20 decreased in SHS and AHS compared to SH and AHS, respectively. Feeding SHS resulted in higher ruminal concentrations of squalene, lanosterol, 3-phenylpropanoic acid, and citrulline compared to SH. The different microbial genes predicted by Tax4Fun were involved in amino sugar and nucleotide sugar metabolism. The pathways of arginine and proline metabolism, purine metabolism, and pyrimidine metabolism were enriched by different metabolites. Moreover, in the SH group, a positive correlation was observed between Prevotella_1 (Bacteroidetes), Prevotellaceae_YAB2003 (Bacteroidetes), and Christensenellaceae_R.7 (Firmicutes), and the metabolites, including citrulline, lanosterol, and squalene. The increased abundances of Prevotella_1 , Ruminococcaceae_UCG.002 , and Prevotellaceae_YAB2003 might result in increased fiber digestion and nutrient utilization but nutrient digestion was not measured in the current study. In summary, saponins have the ability to modulate the ruminal microbial community and ruminal metabolites and thus affect the rumen environment. However, the response seems to be dependent on the composition of the basal diet. This study provides a comprehensive overview of the microbial and biochemical changes in the rumen of cattle fed saponins. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the prevalence and molecular characteristics of ESBL-producing Escherichia coli (ESBL-EC) in faecal samples from dairy cows in China.Methods: In total, 651 faecal samples were collected from cows distributed among the 10 provinces of China. Potential ESBL-EC isolates were cultured on selective medium. The clonal relatedness of the ESBL-EC isolates was assessed using MLST. WGS was conducted on 3 mcr-positive isolates and 14 additional randomly selected ESBL-EC isolates. Southern blot, S1-PFGE and conjugation were performed for mcr-1-carrying isolates. The genetic environment of the pMCR-JLF4 plasmid was also analysed.Results: In total, 290 unique ESBL-EC isolates were detected from 284 cows (43.6%). Alleles of CTX-M were observed in 94.1% (273/290) of all isolates. The most prevalent genotypes observed in this study were blaCTX-M-14, blaCTX-M-15, blaCTX-M-17 and blaCTX-M-55. Differentiation of 79 STs with a polyclonal structure was accomplished using MLST. Clonal complex 10 was the most prevalent major complex detected here. Furthermore, the mcr-1 gene was detected in three isolates. The complete sequence of the mcr-1-containing pMCR-JLF4 was determined. The plasmid was 66.7 kb in length, with a genetic structure of nikA-nikB-mcr-1-pap2. Conjugation analysis confirmed that the mcr-1 gene in pMCR-JLF4 was transferable without the assistance of the ISApl1 gene.Conclusions: The data presented here suggest high prevalence of ESBL-EC in Chinese cow farms. Furthermore, it was clearly demonstrated that commensal E. coli strains can be reservoirs of blaCTX-M genes, potentially contributing to the dissemination and transfer of the mcr-1 gene to pathogenic bacteria among cows. [ABSTRACT FROM AUTHOR]

The beef cattle industry represents a significant portion of the USA's agricultural sect, with beef cattle accounting for the most red meat consumed in the USA. Feed represents the largest input cost in the beef industry, accounting for approximately 70% of total input cost. Given that, novel methods need to be employed to optimize feed efficiency in cattle to reduce monetary cost as well as environmental cost associated with livestock industries, such as methane production and nitrogen release into the environment. The rumen microbiome contributes to feed efficiency by breaking down low-quality feedstuffs into energy substrates that can subsequently be utilized by the host animal. Attempts to manipulate the rumen microbiome have been met with mixed success, though persistent changes have not yet been achieved beyond changing diet. Recent technological advances have made analyzing host-wide effects of the rumen microbiome possible, as well as provided finer resolution of those effects. This manuscript reviews contributing factors to the rumen microbiome establishment or re-establishment following rumen microbiome perturbation, as well as host-microbiome interactions that may be responsible for possible host specificity of the rumen microbiome. Understanding and accounting for the variety of factors contributing to rumen microbiome establishment or re-establishment in cattle will ultimately lead to identification of biomarkers of feed efficiency that will result in improved selection criteria, as well as aid to determine methods for persistent microbiome manipulation to optimize production phenotypes. [ABSTRACT FROM AUTHOR]

The diverse rumen microbiome converts lowquality feedstuffs into usable energy and provides approximately 70% of the energy required by its ruminant host through fermentation byproducts. Due to microbial impacts on host health and productivity, numerous studies have associated rumen microbiome variation with important sustainability phenotypes, such as feed efficiency and methane emissions. Although diet, genetics, and environment contribute to variation in feed efficiency, selection for feed-efficient beef cattle using genetic improvement technologies has helped to understand and improve the persistence and longevity of such phenotypes within the herd. While diet has been considered to be the primary driver for the composition and structure of the rumen microbiome, recent studies have indicated the microbial communities present in the rumen are under low-to-moderate host genetic control. The mutualistic, commensal, and parasitic microorganisms that reside in the rumen and lower gastrointestinal tract of cattle and other ruminants exert enormous influence over animal physiology and performance. The ability to interrogate these systems at great depth has permitted a greater understanding of the microbiological and molecular mechanisms involved in ruminant nutrition and health. The work in our group in the field of beef cattle gut microbiology, as it relates to feed efficiency, permits the exploration of these critical microbial community networks. This knowledge will aid researchers seeking to address the grand challenge of maintaining host-efficient gut microbiomes throughout cattle production operations. This work is supported by the Agriculture and Food Research Initiative grant no. 2020-67015-30832 from the USDA National Institute of Food and Agriculture. [ABSTRACT FROM AUTHOR]

The research aimed to identify the bacteria present in the reproductive tract of dairy cattle at follicular and luteal phases of the estrus cycle. Seven samples of cervical mucus were each obtained from the reproductive tract, at follicular and luteal phase, of fourteen healthy cattle, 2-3 years of age, with body condition scores of 2.0-8.3. Sporet, motility, triple sugar iron agar, mannitol and glucose tests were done to obtain gram characteristics and bacterial morphology, which enabled identification at the genus level. Non-specific bacteria isolated at follicular phase were Staphylococcus (50%), Corynebacterium (25%) and Escherichia (25%). At luteal phase, Staphylococcus (45.5%), Escherichia (45.5%) and Corynebacterium (9%) were isolated. The results suggest that a number of bacteria can be found in the reproductive tract of dairy cattle, both at follicular phase and luteal phase. [ABSTRACT FROM AUTHOR]

This research was done to evaluate the characteristics and probiotic potential of lactic acid bacteria (LAB) isolated from the small intestine of ten three year-old male Ongole crossbred cattle. Ten-centimeter samples were obtained from each small intestine, wastes were removed then samples were placed in sterile sample bottles, and immediately taken to the laboratory for bacterial isolation. The LAB isolates were subjected to low pH tolerance (pH 2 and 4), bile salt resistance, and antimicrobial activity against enteric pathogens Staphylococcus aureus and Eschericia coli. Biochemical assay indicated that isolate was gram positive, rodshaped, catalase negative, and capable of fermenting glucose, mannitol, xylose, rhamnose, sucrose, lactose, arabinose, raffinose and sorbitol. Biochemical and morphological identification suggests that the isolate was Lactobacillus plantarum WPL 117 (strain number of control indicator organisms was Lactobacillus plantarum ATCC 14917). This isolate was able to survive at low pH (2 and 4), tolerated 0.3% bile salts, and capable of inhibiting S. aureus and E. coli. Thus, this isolate can be considered a probiotic candidate for further study. [ABSTRACT FROM AUTHOR]

Abstract: Cattle are a major reservoir of Shiga toxin‐producing Escherichia coli. This study investigated the occurrence of seven major STEC serogroups including O157, O145, O103, O121, O111, O45 and O26 among 578 STEC isolates previously recovered from 559 cattle. The isolates were characterized for serotype and major virulence genes. Polymerase chain reaction revealed that 41.7% (241/578) of isolates belonged to STEC O157, O145, O103, O121, O45 and O26, and 33 distinct serotypes. The 241 isolates corresponded to 16.5% (92/559) of cattle that were STEC positive. The prevalence of cattle that tested positive for at least one of the six serogroups across the five farms was variable ranging from 2.9% to 43.4%. Occurrence rates for individual serogroups were as follows: STEC O26 was found in 10.2% (57/559); O45 in 2.9% (16/559); O145 in 2.5% (14/559); O157 in 1.4% (8/559); O121 in 1.1% (6/559); and O103 in 0.4% (2/559). The following proportions of virulence genes were observed: stx1, 69.3% (167/241); stx2, 96.3% (232/241); eaeA, 7.1% (17/241); ehxA, 92.5% (223/241); and both stx1 and stx2, 62.2% (150/241) of isolates. These findings are evidence that cattle in South Africa carry STEC that belong to six major STEC serogroups commonly incriminated in human disease. However, only a subset of serotypes associated with these serogroups were clinically relevant in human disease. Most STEC isolates carried stx1, stx2 and ehxA but lacked eaeA, a major STEC virulence factor in human disease. [ABSTRACT FROM AUTHOR]

Dairy cattle manure serves as a potential source of contamination and infection of animals, humans and the environment. Manure samples withdrawn from a balloon-type digester during anaerobic digestion were evaluated for the presence of antibiotic-resistant bacterial pathogens. The bacterial load of the samples was determined via a viable plate count method and the recovered isolates were subjected to characterisation and identification. These isolates were employed in antibiotic susceptibility testing using a disc diffusion method against a suite of 10 conventional antibiotics. The multiple antibiotic resistance (MAR) index was calculated and MAR phenotypes were generated. Although all the bacterial pathogens showed a certain degree of resistance to the studied antibiotics, a marked resistance was demonstrated by Campylobacter sp. to co-trimoxazole (87.5%) and nalidixic acid (81.5%). Remarkably, a high resistance (82.42%) was demonstrated against the antibiotic class, macrolide, followed by beta-lactams (40.44%), suggesting that bacterial resistance depended on the chemical structure of the antibiotics. However, individual bacterial isolates varied in resistance to particular antibiotics. Of the 83 bacterial isolates, 40(48.19%) observed MAR > 0.2 and, thus, were described as multidrug-resistant isolates. A total of 28 MAR phenotypes were revealed with the highest frequency of MAR phenotypes (37.5%) expressed against 3 antibiotics. Results indicated a high risk of exposure to various antibiotics and wide diversity of antibiotic resistance. [ABSTRACT FROM AUTHOR]

Objectives: To elucidate the phylogenetic relationships among ST9-MRSA-XII isolates from different sources and their genetic features in colonization of different hosts.Methods: We obtained whole-genome sequences of two ST9-MRSA-XII isolates from nasal swabs associated with live pigs in China, and compared them with 135 previously sequenced genomes of 78 human-associated, 39 bovine and 18 porcine Staphylococcus aureus consisting of 11 MRSA of SCCmecXII, 62 MRSA of other SCCmec types and 62 MSSA. The distribution of diverse mobile genetic elements (MGEs), resistance genes and virulence determinants was investigated in relation to isolate phylogeny. Comparisons of SNPs and small insertion/deletions (indels) were conducted to examine genome-level variation between porcine and bovine ST9-MRSA-XII.Results: Phylogenetic analysis revealed that both of our porcine ST9-MRSA-XII isolates clustered with porcine, bovine and human-associated ST9-MRSA-XII. All of these isolates possessed a novel type V pathogenicity island, νSaα, carrying the von Willebrand-binding protein gene vwb, the immune evasion complex gene scn, the aminoglycoside resistance gene aadE, staphylococcal superantigen-like genes (ssl1-ssl11) and lpl tandem genes. Compared with bovine ST9-MRSA-XII BA01611, our porcine isolates contain non-synonymous nucleotide substitutions in genes encoding adhesins and an indel located in a phosphonate ABC transporter pseudogene.Conclusions: The data suggest transmission of ST9-MRSA-XII among swine, cattle and humans. The extraordinary success of the ST9-MRSA-XII group in colonization of various hosts is likely due to acquisition of many MGEs harbouring functional antimicrobial resistance and virulence genes. Transmission of ST9-MRSA-XII between porcine and bovine hosts was accompanied by changes in binding profile and function in genes involved in metabolism. [ABSTRACT FROM AUTHOR]

Several multiple-media culture systems have become commercially available for on-farm identification of mastitis-associated pathogens. However, the accuracy of these systems has not been thoroughly and independently validated against microbiological evaluations performed by referral laboratories. Therefore, the purpose of the present study was to evaluate the performance of commercially available culture plates (Accumast, Minnesota Easy System, SSGN and SSGNC Quad plates) to identify pathogens associated with clinical mastitis in dairy cows. Milk samples from the affected quarter with clinical mastitis were aerobically cultured with the on-farm culture systems and by two additional reference laboratories. Agreeing results from both standard laboratories were denoted as the reference standard (RS). Accuracy (Ac), sensitivity (Se), specificity (Sp), positive and negative predictive values (PPV and NPV, respectively) and Cohen’s kappa coefficient (k) of on-farm plates were determined based on the RS culture of 211 milk samples. All four plate-systems correctly identified ≥ 84.9% of milk samples with no bacterial growth. Accumast had greater values for all overall predictive factors (Ac, Se, Sp, PPV and NPV) and a substantial agreement (k = 0.79) with RS. The inter-rater agreements of Minnesota, SSGN, and SSGNC with RS were moderate (0.45 ≤ k ≤ 0.55). The effectiveness to categorize bacterial colonies at the genus and species was numerically different amongst the commercial plates. Our findings suggest that Accumast was the most accurate on-farm culture system for identification of mastitis-associated pathogens of the four systems included in the analysis. [ABSTRACT FROM AUTHOR]

The emergence of simultaneous resistance to multiple classes of antibiotics presents an increasing threat. Plasmid-borne multiresistance and integrative conjugative elements have been reported in Pasteurella multocida. We report an alternative strategy for the development of multiresistance observed in a P. multocida strain (Pm238) isolated from calf pneumonia. We identified genes integrated into the chromosomal DNA without known integrative and conjugative elements. These genes conferred resistance to streptomycin (strA), tetracycline (tetB), chloramphenicol (catAIII), and sulphonamides (sulII). We also detected mutation in the quinolone-resistance-determining regions of parC. No plasmids could be isolated from strain Pm238. These results suggest that P. multocida can accumulate multiple resistance determinants on the chromosome as single genes. [ABSTRACT FROM AUTHOR]

Emergence and spread of antimicrobial resistance is a major concern for the dairy industry worldwide. Objectives were to determine: (1) phenotypic and genotypic prevalence of drug-specific resistance for 25 species of non-aureus staphylococci, and (2) associations between presence of resistance determinants and antimicrobial resistance. Broth micro-dilution was used to determine resistance profiles for 1,702 isolates from 89 dairy herds. Additionally, 405 isolates were sequenced to screen for resistance determinants. Antimicrobial resistance was clearly species-dependent. Resistance to quinupristin/dalfopristin was common in Staphylococcus gallinarum (prevalence of 98%), whereas S. cohnii and S. arlettae were frequently resistant to erythromycin (prevalence of 63 and 100%, respectively). Prevalence of resistance was 10% against b-lactams and tetracyclines. In contrast, resistance to antimicrobials critically important for human medicine, namely vancomycin, fluoroquinolones, linezolid and daptomycin, was uncommon (<1%). Genes encoding multidrug-resistance efflux pumps and resistance-associated residues in deducted amino acid sequences of the folP gene were the most frequent mechanisms of resistance, regardless of species. The estimated prevalence of the mecA gene was 17% for S. epidermidis. Several genes, including blaZ, mecA, fexA, erm, mphC, msrA, and tet were associated with drug-specific resistance, whereas other elements were not. There were specific residues in gyrB for all isolates of species intrinsically resistant to novobiocin. This study provided consensus protein sequences of key elements previously associated with resistance for 25 species of non-aureus staphylococci from dairy cattle. These results will be important for evaluating effects of interventions in antimicrobial use in Canadian dairy herds. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the efficacy of the association of the nematophagous fungi (Duddingtonia flagrans-AC001); (Pochonia chlamydosporia-VC4) and (Arthrobotrys robusta-I31) in a pelletised formulation of a sodium alginate matrix. The viability and activity of pellet germination and fungal activity (after encapsulation) were evaluated usingin vitroandin vivotests. Next, 12 heads of cattle, Dutch mestizo x zebu, with an average age of 12 months were dewormed with an anthelmintic. Next, 20 days after treatment with the anthelmintic, the animals were randomly divided into two groups of six animals each, and placed in two paddocks with 7.0 ha each ofBrachiaria decumbenswith historical grazing by animals naturally infected by gastrointestinal nematode parasites. At first, each animal was treated with 2 g of pellets per 10 kg of animal, containing the associated fungi (AC001 + VC4 + I31) administered twice a week in conjunction with commercial feed. Each animal in the control group received 2 g of pellets without mycelia added to the feed. The percentage reduction of infective larvae in thein vitrotest was 94% (p < .01). In thein vivotest, the treated animals with fungal association had lower egg counts per gram of faeces (p < .01) compared to the control group animals – a reduction of 91.8%. The reduction in the number of infective larvae recovered from the pasture was 27.5% at a distance of 0–20 cm from the stool bulk, and 26.7% at a distance of 20–40 cm. This association (AC001 + VC4 + I31) of nematophagous fungi was effective in nematode control. [ABSTRACT FROM AUTHOR]

The paper presents the study of the habitat of mycobacteria in various natural and climatic zones of the Karaganda region, which showed that out of all the isolated cultures, 307 (94.5%) were atypical mycobacteria (M. scrofulaceum, M. avium). At that, 64.5% of atypical mycobacteria cultures (M.scrofulaceum, M. avium) were isolated from the diagnostic material and objects of the external environment of the steppe zone.Thesensitinsfrom epizootic strains of mycobacteria were tested in terms of such criteria as sterility, safety, reactogenicity, lack of sensitizing properties, activity, and specificity. The sensitinswere administered to guinea pigs and cattle using an intradermal needless syringe. Preliminary experiments on guinea pigs found that sensitins had biological and specific activity, identical to avian purified protein derivative tuberculin. The tests of developed sensitinsM. Scrofulaceumand M. avium on 59 cattle showed that the sensitins were highly effective in differentiating nonspecific reactions and demonstrated the expedience of their application.Using sensitins for lifetime differentiation of nonspecific reactions to tuberculin mammalian in healthy animals and cattle recovering from tuberculosis prevents the premature slaughtering of commercially valuable animals of a reproductive age. [ABSTRACT FROM AUTHOR]

The species composition and distribution of ciliates were investigated in the rumen contents of 15 domestic cattle (Bos taurus taurus L.) living in the European part of İstanbul, Turkey. Thirty-five species and 13 morphotypes belonging to 13 genera were identified. The density of rumen ciliates in cattle was 31.8 (± 21.3) × 104 cells ml-1, and the mean number of ciliate species per host was 12.9 ± 4.4. Of the ciliate species, Dasytricha ruminantium, Entodinium simulans, and Isotricha prostoma were the most abundant, each with a prevalence of 93.3%, whereas Diplodinium anisacanthum, D. dogieli, D. rangiferi, Enoploplastron triloricatum, Metadinium medium, and Ostraco' dinium munham were detected only in one animal (6.7% prevalence). Eodinium posterovesiculatum m. bilobosum and D. dogieli are new host records for cattle in Turkey. The infraciliature of M. medium (Entodiniomorphida, Ophryoscolecidae) was examined and detected for the first time. The buccal infraciliature of M. medium was composed of three polybrachykineties, a kinety loop, and paralabial kineties. A large dorso-adoral polybrachykinety, a gentle S-shaped curved vestibular polybrachykinety, and a kinety loop between the dorso-adoral polybrachykinety and adoral polybrachykinety were characteristics. Because of these features, M. medium-type buccal infraciliature was between the Ostracodinium gracile-type buccal infraciliature and the Ostracodinium mammosum-type buccal infraciliature. [ABSTRACT FROM AUTHOR]

Microbiological data on hygiene indicators are important fo r assessment o f hygiene levels in abattoirs and control o f carcass contamination. Risk categorization o f slaughterhouses should be based on a process hygiene output through the use o f indicator organisms - Total Viable Counts (TVC), Enterobacteriaceae counts (EC) and Salmonella spp. - monitored on carcasses. The level o f TVC indicates the overall hygiene in abattoirs (equipment, tools, workers), while the presence o f EC on carcasses can indicate fecal contamination which can occur during slaughter/dressing. Detection o f Salmonella spp. indicates the presence o f pathogens, with potential origin from the farm. The aim o f this study was to assess the slaughter process hygiene in abattoirs o f different sizes and throughputs, a large- and a small-scale abattoir, and to analyze differences in process hygiene levels based on implementation o f their self-control plans, throughout a period offive years for cattle and six years fo r pigs. In the large-scale abattoir, TVC levels were slightly higher on cattle carcasses than on pig carcasses, but were always within the regulatory satisfactory or acceptable ranges. In the small-scale abattoir, low counts o f EC were observed on cattle and pig carcasses, with slightly higher levels on cattle carcasses, but the counts were always within the regulatory satisfactory range. Higher TVC levels on both cattle and pig carcasses were observed in the large-scale abattoir versus the small-scale abattoir, but both abattoirs still showed process hygiene levels within the regulatory satisfactory or acceptable range. Salmonella was recovered only from two pig carcasses in the large-scale abattoir. The study revealed that TVC levels differed more on pig carcasses, while EC levels differed more on cattle carcasses. Process hygiene levels in both abattoirs were always in the allowed regulatory range and also were similar to the hygiene levels in other, developed European countries. [ABSTRACT FROM AUTHOR]

Background: Campylobacter (C.) jejuni is the leading cause of human campylobacteriosis worldwide. We performed a molecular epidemiological study to investigate the genetic relationship among C. jejuni strains isolated from human diarrhoeal patients, broiler products and dairy cattle in Lithuania.Methods: The C. jejuni isolates from human clinical cases, dairy cattle and broiler products were genotyped using multilocus sequence typing (MLST). Allele numbers for each housekeeping gene, sequence type (ST), and clonal complex (CC) were assigned by submitting the DNA sequences to the C. jejuni MLST database ( http://pubmlst.org/campylobacter ). Based on the obtained sequence data of the housekeeping genes a phylogenetic analysis of the strains was performed and a minimum spanning tree (MST) was calculated.Results: Among the 262 C. jejuni strains (consisting of 43 strains isolated from dairy cattle, 102 strains isolated from broiler products and 117 clinical human C. jejuni strains), 82 different MLST sequence types and 22 clonal complexes were identified. Clonal complexes CC21 and CC353 predominated among the C. jejuni strains. On ST-level, five sequence types (ST-5, ST-21, ST-50, ST-464 and ST-6410) were dominating and these five STs accounted for 35.9% (n = 94) of our isolates. In addition, 51 (19.5%) C. jejuni strains representing 27 (32.9%) STs were reported for the first time in the PubMLST database ( http://pubmlst.org/campylobacter ). The highest Czekanowski index or proportional similarity index (PSI) was calculated for C. jejuni strains isolated from human campylobacteriosis cases and broiler products (PSI = 0.32) suggesting a strong link between broiler strains and human cases. The PSI of dairy cattle and human samples was lower (PSI = 0.11), suggesting a weaker link between bovine strains and human cases. The calculated Simpson's index of all C. jejuni isolates showed a high genetic diversity (D = 0.96).Conclusion: Our results suggest that broiler products are the most important source of human campylobacteriosis in Lithuania. The study provides information on MLST type distribution and genetic relatedness of C. jejuni strains from humans, broiler products and dairy cattle in Lithuania for the first time, enabling a better understanding of the transmission pathways of C. jejuni in this country. [ABSTRACT FROM AUTHOR]

Objectives: To identify and characterize a novel cfr variant that recently emerged and confers multidrug resistance in Campylobacter , a major foodborne pathogen.Methods: WGS was initially used to identify the cfr (C) gene in Campylobacter isolates and its function was further verified by cloning into an antibiotic-susceptible Campylobacter jejuni strain. Distribution of cfr (C) in various Campylobacter isolates was determined by PCR analysis. Genotyping of cfr (C)-positive strains was done by PFGE and MLST.Results: The cfr (C) gene is predicted to encode a protein that shares 55.1% and 54.9% identity with Cfr and Cfr(B), respectively. cfr (C) was located on a conjugative plasmid of ∼48 kb. Cloning of cfr (C) into C. jejuni NCTC 11168 and conjugative transfer of the cfr (C)-containing plasmid confirmed its role in conferring resistance to phenicols, lincosamides, pleuromutilins and oxazolidinones, and resulted in an 8-256-fold increase in their MICs in both C. jejuni and Campylobacter coli . The cfr (C) gene was detected in multiple C. coli (34 of 344; 10%) isolates derived from different cattle farms in different states, and molecular typing of the cfr (C)-positive C. coli isolates revealed its spread mainly via clonal expansion.Conclusions: These results identify cfr (C) as a new multidrug resistance mechanism in Campylobacter and suggest the potential transmission of this mechanism via the foodborne route, warranting enhanced efforts to monitor its spread in Campylobacter and other foodborne pathogens. [ABSTRACT FROM AUTHOR]

Antimicrobial agents are used in cattle production systems for the prevention and control of bacterial associated diseases. A consequence of their use is the potential development of antimicrobial resistance (AMR). Enterococcus faecium and Enterococcus faecalis that are resistant to antimicrobials are of increased concern to public health officials throughout the world as they may compromise the ability of various treatment regimens to control disease and infection in human medicine. Australia is a major exporter of beef; however it does not have an ongoing surveillance system for AMR in cattle or foods derived from these animals. This study examined 910 beef cattle, 290 dairy cattle and 300 veal calf faecal samples collected at slaughter for the presence of enterococci. Enterococcus were isolated from 805 (88.5%) beef cattle faeces, 244 (84.1%) dairy cattle faeces and 247 (82.3%) veal calf faeces with a total of 800 enterococci subsequently selected for AMR testing. The results of AMR testing identified high levels of resistance to antimicrobials that are not critically or highly important to human medicine with resistance to flavomycin (80.2%) and lincomycin (85.4–94.2%) routinely observed. Conversely, resistance to antibiotics considered critically or highly important to human medicine such as tigecycline, daptomycin, vancomycin and linezolid was not present in this study. There is minimal evidence that Australian cattle production practices are responsible for disproportionate contributions to AMR development and in general resistance to antimicrobials of critical and high importance in human medicine was low regardless of the isolate source. The low level of antimicrobial resistance in Enterococcus from Australian cattle is likely to result from comprehensive controls around the use of antimicrobials in food-production animals in Australia. Nevertheless, continued monitoring of the effects of all antimicrobial use is required to support Australia’s reputation as a supplier of safe and healthy food. [ABSTRACT FROM AUTHOR]

Background: There is paucity of information regarding the epidemiology of Escherichia coli O157: H7 in developing countries. In this study, we investigated the occurrence of E. coli O157: H7 associated with beef cattle at processing plants and at retail shops in Ethiopia.Methods: Various samples were collected from beef cattle at slaughter/processing plants, carcass at retail shops and humans at health centers. E. coli O157: H7 was isolated, identified and characterized for antimicrobial resistance, using standard microbiological methods.Results: At the processing plants E. coli O157: H7 was detected in 1.89% of fecal, 0.81% of intestinal mucosal swab, 0.54% of skin swab and 0.54% of carcass internal swab samples. At retail shops it was detected in 0.8% of carcass and 0.8% of cutting board swab samples, while all samples from utensils, hands from workers, and fecal and stool samples were negative. All isolates were resistant to Amoxicillin, moderately resistant to Cefoxitine and Nitrofurantoins but susceptible to other antimicrobials tested.Conclusions: E. coli O157: H7 occurs at low prevalence in beef cattle, and the current sanitary dressing procedures in the processing plants and storage conditions in the retail shops are effective against E. coli O157: H7. [ABSTRACT FROM AUTHOR]

Contents This study was conducted to determine the effect of immunization with inhibin DNA vaccine delivered by attenuated Salmonella choleraesuis on ovarian responses and fertility in cross-bred buffaloes. A total of 134 cross-bred buffaloes were divided into four groups: groups T1 ( n = 34), T2 ( n = 35) and T3 ( n = 31) were nasal immunized twice a day with 10 ml of 1 × 1010 CFU/ml of the C501 (pVAX-asd-IS) vaccine for 5, 3 and 1 day, respectively. Group C ( n = 34) was nasal immunized with 10 ml PBS for 5 days. All animals were immunized twice with an interval of 14 days and administered with 200 μg of a GnRH analogue on day 28, 0.5 mg PGF2α on day 35 and 200 μg of the same GnRH analogue on day 37. TAI was performed at 18 and 24 hr after the second GnRH treatment. Fourteen days after primary immunization, C501 (pVAX-asd-IS) elicited significant immune responses, and anti-inhibin IgG antibody titres in group T1 were significantly higher ( p < .01) than groups T3 and C. After the second GnRH treatment, the growth speed of the dominant follicles in group T1 was significantly faster ( p < .05) than groups T3 and C. The number and diameter of large follicles (≥10 mm) as well as ovulatory follicles in group T1 were the greatest in all groups, resulting in a greater conception rate in buffaloes with positive anti-inhibin antibodies. These results demonstrate that immunization with the C501 (pVAX-asd-IS) vaccine, coupled with the Ovsynch protocol, could be used as an alternative approach to improve reproductive performance in cross-bred buffaloes. [ABSTRACT FROM AUTHOR]

Bactrian camels may have a unique gastrointestinal (GI) microbiome because of their distinctive digestive systems, unique eating habits and extreme living conditions. However, understanding of the microbial communities in the Bactrian camel GI tract is still limited. In this study, microbial communities were investigated by comparative analyses of 16S rRNA hypervariable region V4 sequences of fecal bacteria sampled from 94 animals in four population groups: Inner Mongolian cattle (IMG-Cattle), Inner Mongolian domestic Bactrian camels (IMG-DBC), Mongolian domestic Bactrian camels (MG-DBC), and Mongolian wild Bactrian camels (MG-WBC). A total of 2,097,985 high-quality reads were obtained and yielded 471,767,607 bases of sequence. Firmicutes was the predominant phylum in the population groups IMG-Cattle, IMG-DBC and MG-WBC, followed (except in the Inner Mongolian cattle) by Verrucomicrobia. Bacteroidetes were abundant in the IMG-DBC and MG-WBC populations. Hierarchical clustered heatmap analysis revealed that the microbial community composition within the three Bactrian camel groups was relatively similar, and somewhat distinct from that in the cattle. A similar result was determined by principal component analysis, in which the camels grouped together. We also found several species-specific differences in microbial communities at the genus level: for example, Desulfovibrio was abundant in the IMG-DBC and MG-WBC groups; Pseudomonas was abundant in the IMG-Cattle group; and Fibrobacter, Coprobacillus, and Paludibacter were scarce in the MG-WBC group. Such differences may be related to different eating habits and living conditions of the cattle and the various camel populations. [ABSTRACT FROM AUTHOR]

The objective of this study was to characterize blaOXA-23 harbouring Acinetobacter indicus-like strains from cattle including genomic and phylogenetic analyses, antimicrobial susceptibility testing and evaluation of pathogenicity in vitro and in vivo. Nasal and rectal swabs (n = 45) from cattle in Germany were screened for carbapenem-non-susceptible Acinetobacter spp. Thereby, two carbapenem resistant Acinetobacter spp. from the nasal cavities of two calves could be isolated. MALDI-TOF mass spectrometry and 16S rDNA sequencing identified these isolates as A. indicus-like. A phylogenetic tree based on partial rpoB sequences indicated closest relation of the two bovine isolates to the A. indicus type strain A648T and human clinical A. indicus isolates, while whole genome comparison revealed considerable intraspecies diversity. High mimimum inhibitory concentrations were observed for carbapenems and other antibiotics including fluoroquinolones and gentamicin. Whole genome sequencing and PCR mapping revealed that both isolates harboured blaOXA-23 localized on the chromosome and surrounded by interrupted Tn2008 transposon structures. Since the pathogenic potential of A. indicus is unknown, pathogenicity was assessed employing the Galleria (G.) mellonella infection model and an in vitro cytotoxicity assay using A549 human lung epithelial cells. Pathogenicity in vivo (G. mellonella killing assay) and in vitro (cytotoxicity assay) of the two A. indicus-like isolates was lower compared to A. baumannii ATCC 17978 and similar to A. lwoffii ATCC 15309. The reduced pathogenicity of A. indicus compared to A. baumannii correlated with the absence of important virulence genes encoding like phospholipase C1+C2, acinetobactin outer membrane protein BauA, RND-type efflux system proteins AdeRS and AdeAB or the trimeric autotransporter adhesin Ata. The emergence of carbapenem-resistant A. indicus-like strains from cattle carrying blaOXA-23 on transposable elements and revealing genetic relatedness to isolates from human clinical sources requires further investigations regarding the pathogenic potential, genomic characteristics, zoonotic risk and putative additional sources of this new Acinetobacter species. [ABSTRACT FROM AUTHOR]

Escherichia coli O157:H7 is a foodborne pathogen that colonizes ruminants. Cattle are considered the primary reservoir of E. coli O157:H7 with super-shedders, defined as individuals excreting > 104 E. coli O157:H7 CFU g-1 feces. The mechanisms leading to the super-shedding condition are largely unknown. Here, we used 16S rRNA gene pyrosequencing to examine the composition of the fecal bacterial community in order to investigate changes in the bacterial microbiota at several locations along the digestive tract (from the duodenum to the rectal-anal junction) in 5 steers previously identified as super-shedders and 5 non-shedders. The overall bacterial community structure did not differ by E. coli O157:H7 shedding status; but several differences in the relative abundance of taxa and OTUs were noted between the two groups. The genus Prevotella was most enriched in the non-shedders while the genus Ruminococcus and the Bacteroidetes phylum were notably enriched in the super-shedders. There was greater bacterial diversity and richness in samples collected from the lower- as compared to the upper gastrointestinal tract (GI). The spiral colon was the only GI location that differed in terms of bacterial diversity between super-shedders and non-shedders. These findings reinforced linkages between E. coli O157:H7 colonization in cattle and the nature of the microbial community inhabiting the digestive tract of super-shedders. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the epidemiological characteristics and the surrounding genetic structure of the blaNDM-5 gene in Klebsiella pneumoniae derived from dairy cows in Jiangsu Province, China.Methods: Ten carbapenem-resistant K. pneumoniae were collected from three dairy farms and were screened for the presence of carbapenemase genes using PCR and sequencing. PFGE and MLST were conducted to analyse the genetic relatedness of the blaNDM-5-harbouring K. pneumoniae isolates. The location of blaNDM-5 was identified by S1 nuclease-PFGE and Southern blotting. The transferability and profiles of blaNDM-5-carrying plasmids were analysed by conjugation experiments, and PCR-based replicon typing and RFLP, respectively. The surrounding genetic structure of the blaNDM-5 gene was obtained using WGS and PCR mapping.Results: All 10 K. pneumoniae from dairy cows harboured the blaNDM-5 gene, exhibited resistance to multiple antimicrobials and belonged to five STs, of which ST1661 and ST2108 were the most prevalent. The blaNDM-5 gene was located on the ∼46 kb IncX3 plasmid in all isolates and these plasmids could be conjugated to an Escherichia coli recipient with no additional resistance profiles transferred. All blaNDM-5-carrying plasmids shared similar genetic contexts and were nearly identical to that of the human K. pneumoniae plasmid (pNDM-MGR194) previously reported in India.Conclusions: This was the first case of blaNDM-5-positive K. pneumoniae identified from dairy cows in China. The IncX3 pNDM-MGR194-like plasmid disseminated among cow farms should be highlighted and its potential role in mediating transmission of the blaNDM gene between bacteria from humans and animals requires further monitoring. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of increasing the proportion of bison relative to cattle inoculum on fermentation and microbial populations within an artificial rumen (Rusitec). The experiment was a completely randomized design with a factorial treatment structure (proportion cattle:bison inoculum; 0:100, 33:67, 67:33, and 100:0) replicated in two Rusitec apparatuses (n = 8 fermenters). The experiment was 15 d with 8 d of adaptation and 7 d of sampling. Fermenters were fed a diet of 70:30 barley straw:concentrate (DM basis). True digestibility of DM was determined after 48 h of incubation from d 13 to 15, and daily ammonia (NH3) and volatile fatty acid (VFA) production were measured on d 9-12. Protozoa counts were determined at d 9, 11, 13, and 15 and particle-associated bacteria (PAB) from d 13 to 15. Select bacterial populations in the PAB were measured using RT-qPCR. Fermenter was considered the experimental unit and day of sampling as a repeated measure. Increasing the proportion of bison inoculum resulted in a quadratic effect (P < 0.05) on straw, concentrate and total true DM disappearance and on straw and total neutral detergent fiber (aNDF) disappearance, with greater disappearances observed with mixed inoculum. There were no effect of source or proportion of inoculum on ADF disappearance (P > 0.05). Increasing bison inoculum linearly increased (P < 0.05) concentrate aNDF disappearance, total and concentrate N disappearance as well as total daily VFA and acetate production. A positive quadratic response (P < 0.05) was observed for daily NH3-N, propionate, butyrate, valerate, isovalerate and isobutyrate production, as well as the acetate:propionate ratio. Increasing the proportion of bison inoculum linearly increased (P < 0.05) total protozoa numbers. No effects were observed on pH, total gas and methane production, microbial N synthesis, or copies of 16S rRNA associated with total bacteria, Selenomonas ruminantium or Prevotella bryantii. Increasing bison inoculum had a quadratic effect (P < 0.05) on Fibrobacter succinogenes, and tended to linearly (P < 0.10) increase Ruminococcus flavefaciens and decrease (P < 0.05) Ruminococcus albus copy numbers. In conclusion, bison inoculum increased the degradation of feed protein and fiber. A mixture of cattle and bison rumen inoculum acted synergistically, increasing the DM and aNDF disappearance of barley straw. [ABSTRACT FROM AUTHOR]

Poly(3-hydroxybutyrate)-producingEnterococcus faeciumKT722772 was isolated from cattle rumen fluid by Sudan black staining. It was found to be gram-positive cocci. Poly(3-hydroxybutyrate) production usingE. faeciumKT722772 was optimized at different pH ranging from 2 to 7 and with different substrates such as glucose, butyric acid, propionic acid, sodium acetate, and glycerol as a sole carbon source at a concentration ranging from 0 to 4%. Maximum poly 3-hydroxy butyrate production (1.8 g/L) was achieved with 1% butyric acid at pH 7. Poly 3-hydroxy butyrate produced byE. faeciumwas characterized by Fourier transform infrared spectroscopy, thermogravimetric analysis, and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Streptococcus agalactiae is an emerging pathogen of nonpregnant human adults worldwide and a reemerging pathogen of dairy cattle in parts of Europe. To learn more about interspecies transmission of this bacterium, we compared contemporaneously collected isolates from humans and cattle in Finland and Sweden. Multilocus sequence typing identified 5 sequence types (STs) (ST1, 8, 12, 23, and 196) shared across the 2 host species, suggesting possible interspecies transmission. More than 54% of the isolates belonged to those STs. Molecular serotyping and pilus island typing of those isolates did not differentiate between populations isolated from different host species. Isolates from humans and cattle differed in lactose fermentation, which is encoded on the accessory genome and represents an adaptation to the bovine mammary gland. Serotype IV-ST196 isolates were obtained from multiple dairy herds in both countries. Cattle may constitute a previously unknown reservoir of this strain. [ABSTRACT FROM AUTHOR]

Shiga toxin-producing Escherichia coli (STEC) O157:H7 is an important foodborne pathogen worldwide. In Turkey, little is known about the molecular characteristics of STEC O157:H7 isolates. The aim of this study was to examine the genetic diversity of STEC O157:H7 isolates from cattle in Turkey using pulsed-field gel electrophoresis (PFGE). A total of 18 STEC O157:H7 strains were isolated from 540 rectal swab samples of slaughtered cattle in two abattoirs (coded A and B) located in eastern Turkey. The presence of virulence genes (stx1, stx2, hlyA and eae) was detected using the polymerase chain reaction. Of the 18 STEC O157:H7 isolates, 14 had stx2, hlyA, and eae genes. Four of the isolates were positive for stx1, stx2, hlyA, and eae genes. Thirteen different PFGE patterns were observed among the STEC O157:H7 isolates. The most common PFGE pattern was X1, which was detected in six STEC O157:H7 isolates. These six isolates contained the same virulence genes (stx2, eae and hlyA). However, some of the isolates containing the same virulence genes showed different PFGE profiles. Eleven different PFGE patterns were detected among the isolates from abattoir B, and two different PFGE patterns were detected among the isolates from abattoir A. The results of PFGE revealed a wide genetic diversity among the STEC O157:H7 isolates from cattle in Turkey. This is the first study on PFGE typing of STEC O157:H7 isolates from cattle in Turkey and further studies are needed. [ABSTRACT FROM AUTHOR]

Many factors can affect animal feed efficiency which is one of the important economic traits in the beef industry. To date, our understanding of the role of the rumen microbiota and its impact on feed efficiency is largely unknown. The objective of this paper was to determine if the rumen microbiota is associated with residual feed intake (RFI) by studying the metatranscriptome of the rumen microbiome from cattle with different RFI values. The microbial transcriptome profiles revealed that Succinivibrionaceae and Methanomassiliicoccales were the most active microbial phylotypes, occupying approximately 44.1% and 35.6% of the bacterial and archaeal communities in the rumen of steers fed with barley-based diet, respectively. Further, the relative abundance of Lachnospiraceae, Veillonellaceae, and p-2534–18B5 bacterial families and Methanomassiliicoccales archaeal taxa were different between low RFI (L-RFI; efficient) and high RFI (H-RFI; inefficient) beef steers. The microbiome of L-RFI animals possessed characteristics associated with higher metabolic function and cell survivability, suggesting that enhanced fermentation capacity and adaptability of the microbiome may be key factors to improve nutrient availability. Our results provide evidence that the rumen microbiome could be one of the biological factors associated with variation in cattle feed efficiency. [ABSTRACT FROM AUTHOR]

Paramphistomes are parasites of domestic and wild ruminants, the effects of which in animal health remain underestimated. Very few studies in Africa have been done using molecular techniques to resolve situations associated with taxonomical groupings and epidemiology of these parasites. In this study, the genetic variability of nine representative paramphistome isolates collected from southern African countries, namely Botswana, South Africa, Zambia and Zimbabwe, was assessed using both morphological and internal transcribed spacer 2 (ITS2) rDNA sequence data. Morphological characterization and identification were carried out using median sagittal sections of the paramphistomes. DNA of the individual paramphistomes was isolated, the ITS2 rDNA was amplified, purified and sequenced. The sequences were submitted to GenBank, which assigned them the following accession numbers: KP639631, KP639630, KP639632, KP639633, KP639634, KP639635, KP639636, KP639637 and KP639638. These sequences were used for phylogenetic analysis using MEGA 6. Morphological characterization revealed three species of paramphistomes belonging to three different sub-families: one Stephanopharynx compactus isolate, a member of the Stephanopharyngidae sub-family; one Carmyerius dollfusi isolate, a member of the Gastrothylacidae sub-family; and seven Calicophoron microbothrium isolates belonging to the Paramphistomidae sub-family. ITS2 sequence analysis using BlastN results indicated that this is the first report of S. compactus (KP639630) and C. dollfusi (KP639636). Phylogenetic reconstruction of the paramphistome isolates revealed three separate clades representing the three species. However, the clade with all the C. microbothrium isolates was the only one that was supported by a higher bootstrap value of 92%, although there was no differentiation of the isolates according to geographical locations. The low divergence values on the ITS2 sequences of the C. microbothrium isolates indicate that ITS rDNA sequences can be used as a molecular tool to infer knowledge for resolving taxonomic groupings. [ABSTRACT FROM AUTHOR]

Utilizing a transdermal method of inoculation developed in our laboratory, the duration of infection of Salmonella in the peripheral lymph nodes of steers was examined. Thirty-six Holstein steers (mean body weight of 137 kg) were inoculated with Salmonella Montevideo (day 0) on each lower leg and both sides of the back and abdomen. Calves were euthanized beginning at 6 h and subsequently on each of days 1, 2, 4, 7, 9, 11, 14, and 21 postinoculation (four animals each time). The subiliac, popliteal, and superficial cervical (prescapular) lymph nodes were collected and cultured (quantitatively and qualitatively) for the challenge strain of Salmonella. The challenge strain was detected via direct culture within the lymph nodes at 6 h postinoculation and on each subsequent necropsy date. Salmonella levels in lymph node were 0.8 to 1.8 log CFU/g. Lymph nodes were generally positive after enrichment culture throughout the experiment. Salmonella elimination appeared to begin approximately 14 days postinoculation. However, elimination was not completed by day 21; therefore, a second experiment was conducted identical to the first except that the time from inoculation to necropsy was extended. Salmonella was recovered via direct culture on each of the necropsy days, and results in general were similar to those of experiment I, except that on days 20, 24, and 28 isolates from serogroups C2 and E1[ were identified in addition to the inoculation strain Ci in multiple animals. The data from both experiments indicate that after a single inoculation event. Salmonella would be completely cleared by approximately 28 days. Further research with expanded times between inoculation and necropsy is required for verification. [ABSTRACT FROM AUTHOR]

The purpose of this study was to identify relationships between spoligotypes of M. bovis from cattle in Mexico and those reported in countries with free trade of cattle with Mexico: Australia, Canada, New Zealand and the United States of America. Mexican spoligotypes were obtained from isolates collected from cattle in different parts of the country. Spoligotypes from Canada and New Zealand were obtained from different reports in the literature. Those from the United States were obtained from the database of the National Veterinary Services Laboratory in APHIS-USDA. In order to perform the analysis in a single data set, spoligotypes were all converted to binary data and classified according to or . Epidemiologic information included country and species infected. From 3,198 isolates, 174 different spoligotypes were obtained, 95 were orphans. Ninety one percent of the isolates came from the Unites States (n = 1,609) and Mexico (n = 1,323). Spoligotype SB0265 is shared between Canada and the United States in cattle and wildlife. Six spoligotypes, SB0673, SB0121, SB0145, SB0971, SB0140 and SB1165, were frequent in cattle and wildlife in the United States and cattle in Mexico, suggesting wide exchange of strains. Spoligotype SB0669 was found only in Mexico. Spoligotype SB0140 was the most common in Australia and the sixth in the United States and Mexico. In a phylogenetic analysis, spoligotype SB0140 appears as the oldest spoligotype in the data set, suggesting this as the ancestral spoligotype for all spoligotypes in the five countries. Some spoligotypes are shared by animals and humans, corroborating the zoonotic importance of M. bovis. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effect of different dietary levels of concentrate on feed intake, digestibility, ruminal fermentation and microbial population in steers. Eight Nellore steers fitted with ruminal cannulas were used in a double 4 × 4 Latin square design experiment. The dietary treatments consist of four different proportions of concentrate to roughage: 30:70, 40:60, 60:40 and 80:20% in the dry matter, resulting in Diets 30, 40, 60 and 80, respectively. The roughage was corn silage, and the concentrate was composed of corn, soybean meal and urea. Apparent digestibility of organic matter and crude protein showed a linear association with concentrate proportion (p = 0.01), but the increased concentrate levels did not affect the digestibility of fibre. The lowest ruminal pH-values were observed in animals fed with Diet 80, remaining below pH 6.0 from 6 h after feeding, while in the other diets, the ruminal pH was below 6.0 not before 12 h after feeding. After feeding Diet 80, the ammonia concentration in the rumen was significantly the highest. Higher dietary concentrate levels resulted in a linear increase of propionic acid concentrations, a linear reduction of the ratio acetic acid to propionic acid (p < 0.01) and a linear increased synthesis of microbial nitrogen (p < 0.001). The predicted production of methane was lower in diets with greater amounts of concentrate (p = 0.032). The population of methanogens,R. flavefaciensandR. albusdecreased with higher concentrate levels, while the population ofS. ruminantiumincreased (p < 0.05). The results indicate that greater amounts of concentrate do not decrease ruminal pH-values as much as expected and inhibit some cellulolytic bacteria without impairing the dry matter intake and fibre digestibility in Nellore steers. [ABSTRACT FROM AUTHOR]

Background: In the great Limpopo transfrontier conservation area (GLTFCA), there is an increased interface between wildlife and domestic animals, because rural households move their cattle into the game park in search of grazing and watering resources. This creates opportunities for inter-species transmission of infectious diseases, including zoonoses like brucellosis and tuberculosis, which may also pose a health risk to the local rural communities. This study investigated the awareness, perceptions and practices on zoonoses amongst rural cattle owners, commodity chain- and health-workers in three different localities around Gonarezhou National Park (GNP), Zimbabwe, where the interface between wild and domestic animals varies.Methods: A cross-sectional study was conducted in Malipati, Chikombedzi and Chiredzi that are considered to be high-, medium- and low-domestic animal-wildlife interface areas, respectively. Data was collected from cattle owners, commodity chain and health-workers using a semi-structured questionnaire. To determine the public health risk of food-borne zoonoses, their practices with regard to meat and milk consumptions, and measures they take to prevent exposure to infections were assessed. Data were analyzed using descriptive statistics and principal component analysis.Results: Most respondents (52.8 %, 102/193) were cattle owners, followed by health (30.1 %, 58/193) and lastly commodity chain workers (17.1 %, 33/193). Overall 67.4 % (130/193) of the respondents were aware of zoonoses with respective 48, 81.8, and 93.1 % of cattle owners, commodity chain, and health workers, being aware. Significantly more cattle owners (P < 0.05) from medium and low interface areas were aware of zoonoses compared to those from high interface areas. All categories of respondents cited anthrax (69.2 %), rabies (57.7 %), tuberculosis (41.5 %) and brucellosis (23.9 %) as important zoonoses. About half (46.1 %; 89/193) of the respondents perceive wildlife as important reservoirs of zoonoses. High proportions 98.4 % (190/193) and 96.4 % (186/193) of the respondents indicated that they consume meat and milk, respectively. Access to game meat and milk from informal markets was closely associated with consumption of raw meat and milk.Conclusions: Fewer cattle owners from a high interface area of Malipati are aware of zoonoses compared to other areas due to combined effects of limited education and other factors disadvantaging these marginalised areas. This may increase their risk of exposure to zoonoses, considering that consumption of raw meat and milk is common. Thus, awareness campaigns may reduce the public health impact of zoonoses at the interface. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to determine the effectiveness of WGS in identifying resistance genotypes of MDR Escherichia coli and whether these correlate with observed phenotypes.Methods: Seventy-six E. coli strains were isolated from farm cattle and measured for phenotypic resistance to 15 antimicrobials with the Sensititre(®) system. Isolates with resistance to at least four antimicrobials in three classes were selected for WGS using an Illumina MiSeq. Genotypic analysis was conducted with in-house Perl scripts using BLAST analysis to identify known genes and mutations associated with clinical resistance.Results: Over 30 resistance genes and a number of resistance mutations were identified among the E. coli isolates. Resistance genotypes correlated with 97.8% specificity and 99.6% sensitivity to the identified phenotypes. The majority of discordant results were attributable to the aminoglycoside streptomycin, whereas there was a perfect genotype-phenotype correlation for most antibiotic classes such as tetracyclines, quinolones and phenicols. WGS also revealed information about rare resistance mechanisms, such as structural mutations in chromosomal copies of ampC conferring third-generation cephalosporin resistance.Conclusions: WGS can provide comprehensive resistance genotypes and is capable of accurately predicting resistance phenotypes, making it a valuable tool for surveillance. Moreover, the data presented here showing the ability to accurately predict resistance suggest that WGS may be used as a screening tool in selecting anti-infective therapy, especially as costs drop and methods improve. [ABSTRACT FROM AUTHOR]

This study analyzes the occurrence and distribution of phylogenetic groups of 391 strains of Escherichia coli isolated from poultry, cattle, and water buffalo. The frequency of the phylogroups was A = 19%, B1 = 57%, B2 = 2.3%, C = 4.6%, D = 2.8%, E = 11%, and F = 3.3%. Phylogroups A (P < 0.001) and F (P = 0.018) were associated with E. coli strains isolated from poultry, phylogroups B1 (P < 0.001) and E (P = 0.002) were associated with E. coli isolated from cattle, and phylogroups B2 (P = 0.003) and D (P = 0.017) were associated with E. coli isolated from water buffalo. This report demonstrated that some phylogroups are associated with the host analyzed and the results provide knowledge of the phylogenetic composition of E. coli from domestic animals. [ABSTRACT FROM AUTHOR]

Production of extended-spectrum β-lactamases (ESBLs) producing E. coli in animals and different methods of identifications from Ado Ekiti, Ekiti State, Nigeria, were investigated. Three hundred and fifty fecal samples, collected from apparently healthy cattle and pigs, were cultured and identified following standard procedures. ESBL phenotypic detection was carried out using combination disc test, double disc synergism test, and ESBL brilliance agar screening. Molecular detection of TEM, SHV, and CTX-M genes was carried out using standard molecular method. One hundred and fourteen E. coli isolates were recovered from the 350 samples processed, out of which 72 (63.2%) isolates were positive for ESBLs with multiple resistance to the antibiotics used. Eighty-one (71%) isolates were positive for ESBL by combination disc test, 90 (78.9%) were positive for double disc synergism test, and 93 (81.6%) were positive for ESBL brilliance agar. TEM and CTX-M genes were detected in 48 (42.1%) and 51 (44.7%) isolates, respectively. SHV gene was not detected in any of the isolates while TEM and CTX-M were detected in 33 (28.9%) isolates. This study showed high resistance of E. coli to antibiotics, particularly to the third generation cephalosporins. Regular monitoring and regulated use of antibiotics in livestock should be encouraged. [ABSTRACT FROM AUTHOR]