Bovine respiratory disease (BRD) is a multifactorial disorder responsible for severe economic losses in dairy and feedlot herds. Advances in next-generation sequencing mean that microbial communities in clinical samples, including non-culturable bacteria, can be characterized. Our aim was to evaluate the microbiota of the upper respiratory tract of healthy calves and calves with BRD using whole-genome sequencing (shotgun metagenomics). We performed deep nasopharyngeal swabs on 16 Holstein heifer calves (10 healthy and 6 diagnosed with BRD during the study) at 14 and 28 d of life in 1 dairy herd near Ithaca, New York. Total DNA was extracted, and whole-genome sequencing was performed using the MiSeq Illumina platform (Illumina Inc., San Diego, CA). Samples included 5 predominant phyla: Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes, and Tenericutes. At the genus level, we observed differences between groups for Pseudomonas spp. At the species level, Mannheimia haemolytica was the most abundant bacterium detected. We detected significant differences between groups of calves in the relative abundance of Pseudomonas fluorescens. Pasteurella multocida was among the 20 most abundant species, and Moraxella catarrhalis, commonly associated with pneumonia in humans, was detected in all groups. Analysis of resistance to antibiotics and compounds profiling revealed differences in cobalt-zinc-cadmium resistance. Further research to elucidate the role of Moraxella catarrhalis in BRD is warranted. Genes that were resistant to cobalt-zinc-cadmium, observed mostly in calves with BRD, might be associated with difficulties in antibiotic treatment.

Reproductive diseases are a great barrier to dairy production, as they diminish fertility and cause economic loss. In this context, endometritis plays an important role. Different diagnostic techniques exist for endometritis that vary in sensitivity and specificity. This work aimed to evaluate and compare ultrasonographic and histopathological examinations, and combinations thereof, for the diagnosis of endometritis by determining their sensitivity, specificity, and kappa agreement coefficients using endometrial cytology as the gold standard. We developed an adaptive reading score to perform histological examination of the uterus. In this study, 76 Holstein-Friesian cows, 21 to 47 d postpartum, without vaginal catarrh were submitted to gynecological examinations, including ultrasonographic examination, an endometrial cytology examination, and a uterine biopsy. Our results indicate that ultrasonography is a practical and effective diagnostic method, and a combination of the determination of intrauterine fluid and cervical diameter was the most efficient ultrasonographic method, with 50% sensitivity and 88% specificity. Histopathological examination was a useful diagnostic method that provided rich detail on endometrial inflammation, and allowed evaluation of different components of the tissue such as the epithelium, lamina propria, endometrial glands, and blood vessels; this method had 44% sensitivity and 92% specificity for diagnosis of endometritis.

Equilibration of oocytes with cryoprotectants is a prerequisite of low temperature storage. However, cryoprotectant exposure may induce damage via osmotic stress. Knowledge of cell membrane permeability characteristics and their temperature dependence would facilitate the design of cryopreservation protocols in which osmotic stress is minimized and the incidence of intracellular freezing is reduced. To obtain such data, the volume change of donated human oocytes following exposure to cryoprotectant was measured at a variety of temperatures. After removal of cumulus cells, each oocyte was placed in a 5 microl droplet of phosphate-buffered medium. The oocyte was held in position by suction generated using a fine pipette and perfused with 1 ml 1.5 mol/l dimethylsulphoxide (DMSO) at 30, 24 or 10 degrees C. The volume of the oocyte before, during and after perfusion was recorded by videomicroscopy. Oocyte volume was calculated from radius measurements and the Kedem-Katchalsky (K-K) passive coupled transport coefficients, namely L(p) (hydraulic permeability), P(DMSO) (permeability to DMSO) and sigma (reflection coefficient) were derived. The resulting coefficients were L(p) = 1. 65 +/- 0.15, 0.70 +/- 0.06 and 0.28 +/- 0.04 microm/min.atm; P(DMSO) = 0.79 +/- 0.10, 0.25 +/- 0.04 and 0.06 +/- 0.01 microm/s and sigma = 0.97 +/- 0.01, 0.94 +/- 0.03 and 0.96 +/- 0.01 at 30, 24 and 10 degrees C respectively. The activation energy for L(p) was 14.70 and for P(DMSO) was 20.82 kcal/mol. The permeability parameters of human oocytes are higher than those of murine oocytes, suggesting that they require a shorter period of exposure to DMSO with concomitantly reduced toxic effects.

BackgroundBovine respiratory disease (BRD) is an important problem in cattle production that is responsible for economic losses in dairy herds. Mycoplasma spp. are described as an important etiological agent of BRD.HypothesisTo evaluate the occurrence of the most important mycoplasmas in the lower respiratory tract of healthy and BRD cattle in relationship to clinical signs of BRD.AnimalsSixty young dairy cattle were classified as healthy (n = 32) or cattle showing clinical signs of BRD (n = 28).MethodsTracheal lavage samples were collected and added to tubes containing Hayflick media. Mycoplasma spp. were identified by the presence of “fried egg” like colonies, biochemical tests and polymerase chain reaction (PCR). Occurrence of Mollicutes, M. bovis, M. mycoides subsp. mycoides SC and M. dispar was evaluated. The association between clinical signs of BRD and the presence of Mycoplasma spp. also was evaluated.ResultsColonies were obtained from a 1‐year‐old BRD calf only. However, species identification was not possible. Mollicutes (P = .035) and M. dispar (P = .036) were more common in BRD cattle. The relationship between Mollicutes and crackle (P = .057) was not significant. M. dispar was associated to tachypnea (P = .045) and mixed dyspnea (P = .003). Relationships to heart rate (P = .062) and crackle (P = .062) were not significant.Conclusions and clinical importanceThe results confirmed the importance of mycoplasma as an etiologic agent of BRD and suggested M. dispar as part of the respiratory microbiota and its possible role in the development of BRD.

Com o objetivo de estabelecer os valores de referência de parâmetros bioquímicos que avaliem a função hepática, por meio da determinação da atividade enzimática da aspartato-aminotransferase (AST) e da gama-glutamiltransferase (GGT), de bovinos da raça Jersey, criados no Estado de São Paulo, bem como avaliar a influência dos fatores etários, sexuais e da infecção pelo vírus da leucose dos bovinos sobre os referidos parâmetros bioquímicos, foram colhidas e examinadas amostras de soro sangüíneo de 170 animais, sendo 106 fêmeas e 17 machos, considerados clinicamente sadios e não reagentes ao antígeno glicoprotéico (gp51) da cápsula do vírus da leucose dos bovinos e 47 fêmeas soro-reagentes ao mencionado vírus. Os valores de referência obtidos para a AST foram iguais a 33,91±10,99U/l enquanto para a GGT obtiveram-se valores médios de 13,21±12,72U/l. A avaliação dos resultados demonstrou que as transaminases sofreram influência dos fatores etários, pois comprovou-se que os teores séricos da AST aumentaram significativamente com o evoluir da idade, sendo o valor mínimo observado nas bezerras com até 3 meses de idade (26,39±22,17U/l) e valor máximo em vacas com idade entre 48 e 72 meses de idade (38,60±11,24U/l). Para os níveis séricos da GGT observou-se que nas bezerras com até 3 meses de idade os níveis séricos (31,15±38,70U/l) foram maiores do que os observados nos animais mais velhos (entre 8,70±2,40U/l e 14,24±10,37U/l). Nesta pesquisa não foram observadas influências dos fatores sexuais e da infecção pelo vírus da leucose dos bovinos sobre a atividade enzimática das transaminases.

This study aimed to determine the occurrence of Mannheimiahaemolytica, Pasteurella multocida and Mycoplasma spp., in relation to clinical signs of respiratory disease. Tracheobronchial lavage samples were collected from 96 (healthy and unhealthy) cattle in the State of São Paulo, Brazil. Mycoplasma spp. (12.5 %) and Pasteurellamultocida (15.50 %) were the most prevalent species. Bacillus sp., Staphylococcus sp., Escherichia coli, Klebsiella oxytoca, Pseudomonas aeruginosa and Klebsiella pneumoniae were also isolated. Mollicutes (70.83 %), Mycoplasmabovis (2.94 %) and Mycoplasma dispar (38.23 %) were identified using conventional PCR. Submassive sound on acoustic percussion of the thorax was associated with the absence of Mollicutes (P=0.025). Whistling (P=0.076) and coarse crackle (P=0.046) were associated with the absence of Mycoplasma dispar. Clear sound on acoustic percussion of the thorax was associated with the absence of Mycoplasmabovis (P=0.007). Coughing was associated with the presence of Pasteurellamultocida [P=0.035; confidence interval (CI), 1.12-26.89], but its absence was associated with mucopurulent (P=0.0215; CI, 1.55-34.5) and mucoid nasal discharge (P=0.068; CI, 19-28.5), submassive sound (P=0.031; CI, 1.23-75.5), fine crackle (P=0.058; CI, 1.23-20.1) and coarse crackle (P=0.046; CI, 2.38-70.8). The high prevalence of Pasteurella multocida and Mycoplasma spp. in unhealthy calves increases the importance of these micro-organisms in the pathogenesis of respiratory diseases. This study increases the information about the role of Mycoplasma dispar in respiratory diseases. Differences in some species in relation to clinical signs can be applied as a presumptive diagnosis.

No abstract

No abstract