589 research outputs found

    Detecting and predicting changes in milk homogeneity using data from automatic milking systems

    Get PDF
    To ensure milk quality and detect cows with signs of mastitis, visual inspection of milk by prestripping quarters before milking is recommended in many countries. An objective method to find milk changed in homogeneity (i.e., with clots) is to use commercially available inline filters to inspect the milk. Due to the required manual labor, this method is not applicable in automatic milking systems (AMS). We investigated the possibility of detecting and predicting changes in milk homogeneity using data generated by AMS. In total, 21,335 quarter-level milk inspections were performed on 5,424 milkings of 624 unique cows on 4 farms by applying visual inspection of inline filters that assembled clots from the separate quarters during milking. Images of the filters with clots were scored for density, resulting in 892 observations with signs of clots for analysis (77% traces or mild cases, 15% moderate cases, and 8% heavy cases). The quarter density scores were combined into 1 score indicating the presence of clots during a single cow milking and into 2 scores summarizing the density scores in cow milkings during a 30-h sampling period. Data generated from the AMS, such as milk yield, milk flow, conductivity, and online somatic cell counts, were used as input to 4 multilayer perceptron models to detect or predict single milkings with clots and to detect milking periods with clots. All models resulted in high specificity (98-100%), showing that the models correctly classified cow milkings or cow milking periods with no clots observed. The ability to successfully classify cow milkings or cow periods with observed clots had a low sensitivity. The highest sensitivity (26%) was obtained by the model that detected clots in a single milking. The prevalence of clots in the data was low (2.4%), which was reflected in the results. The positive predictive value depends on the prevalence and was relatively high, with the highest positive predictive value (72%) reached in the model that detected clots during the 30-h sampling periods. The misclassification rate for cow milkings that included higher-density scores was lower, indicating that the models that detected or predicted clots in a single milking could better distinguish the heavier cases of clots. Using data from AMS to detect and predict changes in milk homogeneity seems to be possible, although the prediction performance for the definitions of clots used in this study was poor

    Inside UNLV

    Full text link

    Homogeneity density scores of quarter milk in automatic milking systems

    Get PDF
    Milk quality and clinical mastitis in dairy cows are monitored by detecting visually abnormal milk. A standardized method to evaluate clots in milk and studies of the incidence and dynamics of clots in milk at the quarter level are lacking. We validated a method to score clot density in quarter milk samples and describe the prevalence and dynamics of the density scores between consecutive samplings and periods in 4 farms with automatic milking systems. Using in-line filters, we collected quarter milk samples at each milking during 3 periods of 30 h each in each farm. Clot density was scored based on coverage of the filter area as 0 (negative), 1 (trace), 2 (mild), 3 (moderate), 4 (heavy), and 5 (very heavy). The score for a specific quarter and milking is referred to as the quarter milking score (QMS). Three assessors independently scored 902 images of filter samples with a Fleiss kappa value of 0.72. In total, 21,202 quarter milk samples from 5,398 milkings of 621 cows were collected. Of the quarter filter samples, 2.4% had visible clots, distributed as mild (1.4%), moderate (0.6%), heavy (0.3%), and very heavy (= 4, corresponding to 9.4% of all periods, harbored 86% and 94% of all QMS of 2 to 5 and 3 to 5, respectively. Of these cases, cows sampled in all 3 periods and clots in only 1 period had a quarter period sum score >= 1 in 1.8 different quarters in average. Corresponding numbers for the cows with clots or traces in 2 or 3 periods were 2.2 and 2.5 different quarters, respectively. A QMS of 2 to 5 in the preceding milking increased the chance of a QMS >1 in the following milking, with an average chance of 38%. The probability of a QMS > 1 increased with increasing previous QMS, a higher sum of QMS during the milking period, longer milking interval, and higher lactation number, but decreased with increasing days in milk. Our study showed that the method of clot-density scoring is feasible to perform and reproducible for investigating the occurrence and dynamics of clots in milk. Elevated clot-density scores clustered within certain cows and cow periods and appeared in new quarters of the cows over time. The low recurrence of QMS of 1 and 2 within quarters indicated that QMS 3 could be a reasonable threshold for detecting quarters with abnormal milk that require further attention

    Ubiquitous Expression of Marker Transgenes in Mice and Rats

    Get PDF
    AbstractThe ability to unambiguously mark a cell's genotype is essential for studies in which genetically distinct cell populations must be distinguished from one another in vivo. One approach to this challenge has been the creation of transgenic mice expressing a transgene marker that is easily detectable, with no background staining. Multiple transgenic mouse strains bearing constructs with different combinations of promoter elements and coding sequences have been described, each with its own advantages and limitations. In this report we describe the use of an 800-bp promoter fragment isolated from the ÎČgeo integration site in ROSA26 mice to target expression of two marker genes. We demonstrate that the ROSA26 promoter directs ubiquitous expression of human placental alkaline phosphatase and enhanced green fluorescent protein during embryonic and postnatal development in mouse and rat. We further demonstrate the general utility of these transgenes for marking donor cells in transplantation studies

    HIV/AIDS awareness and risk behaviour among pregnant women in Semey, Kazakhstan, 2007

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Central Asia has one of the most rapidly increasing HIV prevalence in the world. The aim of this study was to evaluate current knowledge, risk behaviour and attitudes to voluntary counselling and testing concerning HIV/AIDS among pregnant women in Semey, Kazakhstan.</p> <p>Methods</p> <p>We collected 226 questionnaires in a consecutive sample from a population on 520 pregnant women. The results were related to ethnicity, age and education level.</p> <p>Results</p> <p>Ninety-six percent had heard about HIV.</p> <p>Positive findings were that 89% and 86% of the women were aware of the two main routes of transmission: sexual intercourses without a condom and sharing needles while injecting drugs. The women had first heard about HIV/AIDS through the media with, 52%, and at school with 40%. Only 46% and 68% of the women pointed out breastfeeding and mother-to-child transmission during pregnancy or delivery as routes of transmission. Eighty-three percent were prepared not to breastfeed their baby if they were found to be HIV positive. Slightly more, 86%, accepted the need to take medicine, but fewer women, 68%, were positive to Caesarean section. Negative findings were that only 28% answered that there are ways to protect oneself against sexually transmitted HIV/AIDS and specified that this was condom use.</p> <p>Conclusion</p> <p>The pregnant women in Semey have poor knowledge about specific mother-to-child HIV transmission and do not know about the means of reducing mother-to-child HIV infection. The information in the public health program needs to be improved. However, most of the women in Semey were positive to prevention strategies for mother-to-child transmission after hearing about it.</p

    Understanding illnesses through a film festival: an observational study

    Get PDF
    Audio-visual materials play a fundamental role in the context of education, care and clinical treatment, as they seem to have a high impact on public awareness. This study aims to describe what messages are perceived by the society at an International Festival of Short Films and Art on Diseases that may help to understand difficult topics, such as illness, dying and suffering. Through an observational, descriptive, cross-sectional study, using full participant observation and an open, self-administered questionnaire, 32 short films were analysed during a healthcare art festival. Categories were developed using inductive content analysis. The message perceived by the participants, after the viewing of the shorts and reflection of the debates among the attendees, were considered in four categories: i) creative and positive education is possible; ii) awareness of preconception and practical duties; iii) meaning of life changes the experience of illness; iv) family and caregivers also experienced suffering. The short films are considered as an excellent tool to generate social dialogue and debate. Public events can be understood as an opportunity to ac- quire, in an emotional and critical manner, other competencies for public awareness. Together, they are capable of communicating difficult messages through a fast, positive, and creative way

    Using cage ladders as a handling device reduces aversion and anxiety in laboratory mice, similar to tunnel handling

    Get PDF
    Summary Handling laboratory animals for husbandry and other procedures can be an important source of anxiety and stress, compromising animal welfare as well as the reliability of research that is sensitive to background stressors. Studies have revealed that picking up laboratory mice by the tail induces aversion, anxiety, physiological stress and depression-like behaviour, but such negative responses can be reduced substantially by using a handling tunnel that mice enter readily with minimal familiarisation. It has not been tested whether anxiety and aversion can be reduced similarly by using other objects to lift up mice from their home cage. Here we compared the willingness of C57BL/6NRj mice to interact voluntarily with their handler after being picked up either on a plastic ladder present in the home cage, or inside a familiar tunnel, or lifted by the base of the tail and then returned to the home cage. We also tested anxiety in open field and elevated plus maze tests once animals were familiarised with their assigned handling method. While mice picked up briefly by the tail were unwilling to interact with the hand that picked them up, mice picked up by ladder or tunnel readily approached, climbed on or entered these devices, with no significant difference in time spent with ladder or tunnel. Anxiety in an unfamiliar open field was reduced to a similar extent in ladder and tunnel handled mice compared with those picked up by the tail. Mice handled by tunnel also showed reduced anxiety in an elevated plus maze compared to those handled by tail, while ladder handling resulted in an intermediate response. Our study shows that, like tunnels, using home cage ladders to pick up mice reduces anxiety and avoids the aversion that is induced by picking up mice by their tails. We discuss the potential practicality of using ladders and tunnels to handle mice in different contexts

    Pancreatic tumor pathogenesis reflects the causative genetic lesion.

    Full text link

    Sinking properties of some phytoplankton shapes and the relation of form resistance to morphological diversity of plankton – an experimental study

    Get PDF
    Form resistance (Phi) is a dimensionless number expressing how much slower or faster a particle of any form sinks in a fluid medium than the sphere of equivalent volume. Form resistance factors of PVC models of phytoplankton sinking in glycerin were measured in a large aquarium (0.6 x 0.6 x 0.95 m). For cylindrical forms, a positive relationship was found between Phi and length/ width ratio. Coiling decreased Phi in filamentous forms. Form resistance of Asterionella colonies increased from single cells up to 6-celled colonies than remained nearly constant. For Fragilaria crotonensis chains, no such upper limit to Phi was observed in chains of up to 20 cells ( longer ones were not measured). The effect of symmetry on Phi was tested in 1 - 6-celled Asterionella colonies, having variable angles between the cells, and in Tetrastrum staurogeniaeforme coenobia, having different spine arrangements. In all cases, symmetric forms had considerably higher form resistance than asymmetric ones. However, for Pediastrum coenobia with symmetric/asymmetric fenestration, no difference was observed with respect to symmetry. Increasing number and length of spines on Tetrastrum coenobia substantially increased Phi. For a series of Staurastrum forms, a significant positive correlation was found between arm-length/cell-width ratio and Phi: protuberances increased form resistance. Flagellates (Rhodomonas, Gymnodinium) had a Phi 1. The highest value ( Phi = 8.1) was established for a 20-celled Fragilaria crotonensis chain. Possible origin of the so-called 'vital component' ( a factor that shows how much slower viable populations sink than morphologically similar senescent or dead ones) is discussed, as is the role of form resistance in evolution of high diversity of plankton morphologies
    • 

    corecore