1,720,983 research outputs found
Management factors affecting dairy calf growth in north-eastern Italy
No full textCalf management, especially from birth to weaning, is extremely important to guarantee optimal health, growth and future performance of replacement heifers. The aim of this study was to evaluate the manage-ment procedures in the very first stages of the calf’s life until weaning and identify those that affect calf growth the most. The trial was conducted on 31 dairy farms, milking from 35 to 600 dairy cows and producing on average from 17 to 40 kg/head/day. From July to December 2018, each farmer was interviewed about all procedures related to calf management from birth to weaning. Some of the procedures evaluated were navel disinfection, separation from the dam, colostrum management, disease prevention, bedding removal, cleaning of housing facilities and calf feeding. The facilities were thoroughly described, measured and assessed for cleanliness. Female calves between 1 and 70 d of age were measured for weight and height at withers. A stepwise regression was performed to identify the principal factors affecting average daily gain (ADG) the most. Farms were grouped by size and milk yield and were tested for differences in ADG (ANOVA) or management procedures (Kruskal-Wallis test). Altogether 271 calves were measured. On average, body weight at weaning was 89.7 ± 15.1kg, and average daily gain in the first 2 mo of life was 0.77 ± 0.19 kg/d. Of all factors considered to explain the ADG until weaning, the stepwise regression selected the amount of colostrum given within 6 h from birth, dam vaccination against enteric diseases, frequency at which colostrum quality is measured and type of colostrum given (R2 = 0.98). None of the factors related to the facili-ties’ cleanliness, animal density or concentrate feeding were selected. Regarding the selected factors, the 26% of the farms fed more than 3L of colostrum within 6 h from the birth, 55% vaccinated the dams against enteric diseases, 16% constantly measured the colostrum quality and 48% fed only maternal colostrum. Farm size and milk yield did not affect ADG nor selected factors, except for frequency at which colostrum quality was measured, that was higher (P = 0.027) in high yield farms
Investigation on Individual and Collective PV Self-Consumption for a Fifth Generation District Heating Network
Get PDFRenewable Energy Communities have been recently introduced in European legislation to promote distributed generation from renewable energy sources. In fact, they allow to produce and consume energy from shared local power plants. Low temperature district heating and cooling networks with distributed heat pumps have demonstrated their capability to exploit renewable and waste heat sources in the urban environment. Therefore, they are considered a promising infrastructure to help decarbonize the building sector. As their main operating cost is the electricity purchased by the utility for heat pumps and circulation pumps, this work investigates whether a Renewable Energy Community could help mitigate such cost by sharing electricity produced by local photovoltaic (PV) systems. The research relies on computer simulations performed with both physical and statistical models for the evaluation of electrical load profiles at the district level. Results show that due to the different seasonality between heating demand and PV production, the increase in self-consumption due to the distributed heat pumps is lower than 10%. The use of batteries does not seem convenient for the same reason. The environmental benefit of the proposed system is evident, with CO2 emissions reduced by 72–80% compared to the current situation depending on PV power installed. It also emerged that PV sharing significantly improves the self-consumption at the district level, in particular when the installed PV power is limited (+45%). In conclusion, results suggest that current incentives on PV-sharing make Renewable Energy Communities a viable option to improve the techno-economic performance of fifth-generation district heating and cooling networks
Effect of different formulation of oligoelements on the health and the performance of beef cattle during conditioning phase
No full textTo improve the efficiency of lifestock production it is important to focus on the conditioning phase, after the arrival of the animals. One of the major problem is related to stressors, such as regrouping and movements of animals, which can affect the development of the immune profile. The aim of this study was to assess the effect of two different vitamin and mineral integration on the performance and the health of beef cattle during the first period of breeding The study was conducted on 107 young charolaise bulls during the first 46 days of breeding. Animals were grouped according to weight. (407 ± 23 kg), and age (300±53) in 11 pens; 5 pens (47 animals in total), were fed with a standard integration and 6 pens (60 animal in total) with an experimental integrator. Feed intake for group, rumination time and activity of each animal were measured daily. Total mixed ration (TMR) samples and residual samples were collected weekly, submitted to chemical analyses and shieved with a modify Penn State separator. Temperature Humidity Index (THI) was measured weekly. The trial was divided into 2 periods
Weight, average daily gain, activity and rumination time data were analyzed by ANOVA and PROC GLM (SAS). Mineral integration (Control vs Experimental), pen (within diet) and period were used as fixed factors, while the initial weight was used as a covariable. A Z test was conducted in order to establish the different risks between groups on the onset of Bovine Respiratory Distress syndrome (BRD).
The control and experimental group (C vs SP) had a Dry Matter Intake (DMI) of 8,14 and 7,70 kg/d during the first period and 8,44 and 8,31 kg/d during the second period.( P=0,291) The average mean value of the C and SP group for both periods were of 8,29 and 8,00 kg/d respectively, and no significant differences were found between groups (P=0,567). In addition, no significant effects were observed for weight due to different integration (464 kg vs 468 C vs SP; P= 0.562), though significant effects were found due to period (447,5 vs 485 C vs SP; P< 0.001), with a higher weight in the second phase. The subjects of the SP group showed an Avarage Daily Gain (AVG) 10% higher than the control (1.72 vs. 1.56 kg/d) and this difference was statistically significant (P = 0.05).
There were no statistically significant differences in feed efficiency and rumination time between C vs SP group. This can be related to the high individual animal variability. A tendency to significance were reported for the activity (P=0,085).
Five animals were found to be affected by BRD (six cases in total), two in the SP group and 4 in the C group, but no significance evidence emerged.(2 vs 4, respectively; P=0.492).
The outcomes of the study suggest that the experimental integration resulted more efficient in improving the average daily gain, probably due to a major oligoelement biodisponibily, and that can lead to an increase of cattle performances. More studies are needed to investigate the effects on rumination time and activity
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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